security/selinux/hooks.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *  NSA Security-Enhanced Linux (SELinux) security module
   4  *
   5  *  This file contains the SELinux hook function implementations.
   6  *
   7  *  Authors:  Stephen Smalley, <sds@tycho.nsa.gov>
   8  *            Chris Vance, <cvance@nai.com>
   9  *            Wayne Salamon, <wsalamon@nai.com>
  10  *            James Morris <jmorris@redhat.com>
  11  *
  12  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  13  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  14  *                                         Eric Paris <eparis@redhat.com>
  15  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  16  *                          <dgoeddel@trustedcs.com>
  17  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  18  *      Paul Moore <paul@paul-moore.com>
  19  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  20  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  21  *  Copyright (C) 2016 Mellanox Technologies
  22  */
  23
  24 #include <linux/init.h>
  25 #include <linux/kd.h>
  26 #include <linux/kernel.h>
  27 #include <linux/kernel_read_file.h>
  28 #include <linux/tracehook.h>
  29 #include <linux/errno.h>
  30 #include <linux/sched/signal.h>
  31 #include <linux/sched/task.h>
  32 #include <linux/lsm_hooks.h>
  33 #include <linux/xattr.h>
  34 #include <linux/capability.h>
  35 #include <linux/unistd.h>
  36 #include <linux/mm.h>
  37 #include <linux/mman.h>
  38 #include <linux/slab.h>
  39 #include <linux/pagemap.h>
  40 #include <linux/proc_fs.h>
  41 #include <linux/swap.h>
  42 #include <linux/spinlock.h>
  43 #include <linux/syscalls.h>
  44 #include <linux/dcache.h>
  45 #include <linux/file.h>
  46 #include <linux/fdtable.h>
  47 #include <linux/namei.h>
  48 #include <linux/mount.h>
  49 #include <linux/fs_context.h>
  50 #include <linux/fs_parser.h>
  51 #include <linux/netfilter_ipv4.h>
  52 #include <linux/netfilter_ipv6.h>
  53 #include <linux/tty.h>
  54 #include <net/icmp.h>
  55 #include <net/ip.h>             /* for local_port_range[] */
  56 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  57 #include <net/inet_connection_sock.h>
  58 #include <net/net_namespace.h>
  59 #include <net/netlabel.h>
  60 #include <linux/uaccess.h>
  61 #include <asm/ioctls.h>
  62 #include <linux/atomic.h>
  63 #include <linux/bitops.h>
  64 #include <linux/interrupt.h>
  65 #include <linux/netdevice.h>    /* for network interface checks */
  66 #include <net/netlink.h>
  67 #include <linux/tcp.h>
  68 #include <linux/udp.h>
  69 #include <linux/dccp.h>
  70 #include <linux/sctp.h>
  71 #include <net/sctp/structs.h>
  72 #include <linux/quota.h>
  73 #include <linux/un.h>           /* for Unix socket types */
  74 #include <net/af_unix.h>        /* for Unix socket types */
  75 #include <linux/parser.h>
  76 #include <linux/nfs_mount.h>
  77 #include <net/ipv6.h>
  78 #include <linux/hugetlb.h>
  79 #include <linux/personality.h>
  80 #include <linux/audit.h>
  81 #include <linux/string.h>
  82 #include <linux/mutex.h>
  83 #include <linux/posix-timers.h>
  84 #include <linux/syslog.h>
  85 #include <linux/user_namespace.h>
  86 #include <linux/export.h>
  87 #include <linux/msg.h>
  88 #include <linux/shm.h>
  89 #include <linux/bpf.h>
  90 #include <linux/kernfs.h>
  91 #include <linux/stringhash.h>   /* for hashlen_string() */
  92 #include <uapi/linux/mount.h>
  93 #include <linux/fsnotify.h>
  94 #include <linux/fanotify.h>
  95
  96 #include "avc.h"
  97 #include "objsec.h"
  98 #include "netif.h"
  99 #include "netnode.h"
 100 #include "netport.h"
 101 #include "ibpkey.h"
 102 #include "xfrm.h"
 103 #include "netlabel.h"
 104 #include "audit.h"
 105 #include "avc_ss.h"
 106
 107 struct selinux_state selinux_state;
 108
 109 /* SECMARK reference count */
 110 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 111
 112 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 113 static int selinux_enforcing_boot __initdata;
 114
 115 static int __init enforcing_setup(char *str)
 116 {
 117         unsigned long enforcing;
 118         if (!kstrtoul(str, 0, &enforcing))
 119                 selinux_enforcing_boot = enforcing ? 1 : 0;
 120         return 1;
 121 }
 122 __setup("enforcing=", enforcing_setup);
 123 #else
 124 #define selinux_enforcing_boot 1
 125 #endif
 126
 127 int selinux_enabled_boot __initdata = 1;
 128 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 129 static int __init selinux_enabled_setup(char *str)
 130 {
 131         unsigned long enabled;
 132         if (!kstrtoul(str, 0, &enabled))
 133                 selinux_enabled_boot = enabled ? 1 : 0;
 134         return 1;
 135 }
 136 __setup("selinux=", selinux_enabled_setup);
 137 #endif
 138
 139 static unsigned int selinux_checkreqprot_boot =
 140         CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
 141
 142 static int __init checkreqprot_setup(char *str)
 143 {
 144         unsigned long checkreqprot;
 145
 146         if (!kstrtoul(str, 0, &checkreqprot)) {
 147                 selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
 148                 if (checkreqprot)
 149                         pr_warn("SELinux: checkreqprot set to 1 via kernel parameter.  This is deprecated and will be rejected in a future kernel release.\n");
 150         }
 151         return 1;
 152 }
 153 __setup("checkreqprot=", checkreqprot_setup);
 154
 155 /**
 156  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 157  *
 158  * Description:
 159  * This function checks the SECMARK reference counter to see if any SECMARK
 160  * targets are currently configured, if the reference counter is greater than
 161  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 162  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 163  * policy capability is enabled, SECMARK is always considered enabled.
 164  *
 165  */
 166 static int selinux_secmark_enabled(void)
 167 {
 168         return (selinux_policycap_alwaysnetwork() ||
 169                 atomic_read(&selinux_secmark_refcount));
 170 }
 171
 172 /**
 173  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 174  *
 175  * Description:
 176  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 177  * (1) if any are enabled or false (0) if neither are enabled.  If the
 178  * always_check_network policy capability is enabled, peer labeling
 179  * is always considered enabled.
 180  *
 181  */
 182 static int selinux_peerlbl_enabled(void)
 183 {
 184         return (selinux_policycap_alwaysnetwork() ||
 185                 netlbl_enabled() || selinux_xfrm_enabled());
 186 }
 187
 188 static int selinux_netcache_avc_callback(u32 event)
 189 {
 190         if (event == AVC_CALLBACK_RESET) {
 191                 sel_netif_flush();
 192                 sel_netnode_flush();
 193                 sel_netport_flush();
 194                 synchronize_net();
 195         }
 196         return 0;
 197 }
 198
 199 static int selinux_lsm_notifier_avc_callback(u32 event)
 200 {
 201         if (event == AVC_CALLBACK_RESET) {
 202                 sel_ib_pkey_flush();
 203                 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 204         }
 205
 206         return 0;
 207 }
 208
 209 /*
 210  * initialise the security for the init task
 211  */
 212 static void cred_init_security(void)
 213 {
 214         struct cred *cred = (struct cred *) current->real_cred;
 215         struct task_security_struct *tsec;
 216
 217         tsec = selinux_cred(cred);
 218         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 219 }
 220
 221 /*
 222  * get the security ID of a set of credentials
 223  */
 224 static inline u32 cred_sid(const struct cred *cred)
 225 {
 226         const struct task_security_struct *tsec;
 227
 228         tsec = selinux_cred(cred);
 229         return tsec->sid;
 230 }
 231
 232 /*
 233  * get the objective security ID of a task
 234  */
 235 static inline u32 task_sid(const struct task_struct *task)
 236 {
 237         u32 sid;
 238
 239         rcu_read_lock();
 240         sid = cred_sid(__task_cred(task));
 241         rcu_read_unlock();
 242         return sid;
 243 }
 244
 245 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 246
 247 /*
 248  * Try reloading inode security labels that have been marked as invalid.  The
 249  * @may_sleep parameter indicates when sleeping and thus reloading labels is
 250  * allowed; when set to false, returns -ECHILD when the label is
 251  * invalid.  The @dentry parameter should be set to a dentry of the inode.
 252  */
 253 static int __inode_security_revalidate(struct inode *inode,
 254                                        struct dentry *dentry,
 255                                        bool may_sleep)
 256 {
 257         struct inode_security_struct *isec = selinux_inode(inode);
 258
 259         might_sleep_if(may_sleep);
 260
 261         if (selinux_initialized(&selinux_state) &&
 262             isec->initialized != LABEL_INITIALIZED) {
 263                 if (!may_sleep)
 264                         return -ECHILD;
 265
 266                 /*
 267                  * Try reloading the inode security label.  This will fail if
 268                  * @opt_dentry is NULL and no dentry for this inode can be
 269                  * found; in that case, continue using the old label.
 270                  */
 271                 inode_doinit_with_dentry(inode, dentry);
 272         }
 273         return 0;
 274 }
 275
 276 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 277 {
 278         return selinux_inode(inode);
 279 }
 280
 281 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
 282 {
 283         int error;
 284
 285         error = __inode_security_revalidate(inode, NULL, !rcu);
 286         if (error)
 287                 return ERR_PTR(error);
 288         return selinux_inode(inode);
 289 }
 290
 291 /*
 292  * Get the security label of an inode.
 293  */
 294 static struct inode_security_struct *inode_security(struct inode *inode)
 295 {
 296         __inode_security_revalidate(inode, NULL, true);
 297         return selinux_inode(inode);
 298 }
 299
 300 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 301 {
 302         struct inode *inode = d_backing_inode(dentry);
 303
 304         return selinux_inode(inode);
 305 }
 306
 307 /*
 308  * Get the security label of a dentry's backing inode.
 309  */
 310 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
 311 {
 312         struct inode *inode = d_backing_inode(dentry);
 313
 314         __inode_security_revalidate(inode, dentry, true);
 315         return selinux_inode(inode);
 316 }
 317
 318 static void inode_free_security(struct inode *inode)
 319 {
 320         struct inode_security_struct *isec = selinux_inode(inode);
 321         struct superblock_security_struct *sbsec;
 322
 323         if (!isec)
 324                 return;
 325         sbsec = inode->i_sb->s_security;
 326         /*
 327          * As not all inode security structures are in a list, we check for
 328          * empty list outside of the lock to make sure that we won't waste
 329          * time taking a lock doing nothing.
 330          *
 331          * The list_del_init() function can be safely called more than once.
 332          * It should not be possible for this function to be called with
 333          * concurrent list_add(), but for better safety against future changes
 334          * in the code, we use list_empty_careful() here.
 335          */
 336         if (!list_empty_careful(&isec->list)) {
 337                 spin_lock(&sbsec->isec_lock);
 338                 list_del_init(&isec->list);
 339                 spin_unlock(&sbsec->isec_lock);
 340         }
 341 }
 342
 343 static void superblock_free_security(struct super_block *sb)
 344 {
 345         struct superblock_security_struct *sbsec = sb->s_security;
 346         sb->s_security = NULL;
 347         kfree(sbsec);
 348 }
 349
 350 struct selinux_mnt_opts {
 351         const char *fscontext, *context, *rootcontext, *defcontext;
 352 };
 353
 354 static void selinux_free_mnt_opts(void *mnt_opts)
 355 {
 356         struct selinux_mnt_opts *opts = mnt_opts;
 357         kfree(opts->fscontext);
 358         kfree(opts->context);
 359         kfree(opts->rootcontext);
 360         kfree(opts->defcontext);
 361         kfree(opts);
 362 }
 363
 364 enum {
 365         Opt_error = -1,
 366         Opt_context = 0,
 367         Opt_defcontext = 1,
 368         Opt_fscontext = 2,
 369         Opt_rootcontext = 3,
 370         Opt_seclabel = 4,
 371 };
 372
 373 #define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
 374 static struct {
 375         const char *name;
 376         int len;
 377         int opt;
 378         bool has_arg;
 379 } tokens[] = {
 380         A(context, true),
 381         A(fscontext, true),
 382         A(defcontext, true),
 383         A(rootcontext, true),
 384         A(seclabel, false),
 385 };
 386 #undef A
 387
 388 static int match_opt_prefix(char *s, int l, char **arg)
 389 {
 390         int i;
 391
 392         for (i = 0; i < ARRAY_SIZE(tokens); i++) {
 393                 size_t len = tokens[i].len;
 394                 if (len > l || memcmp(s, tokens[i].name, len))
 395                         continue;
 396                 if (tokens[i].has_arg) {
 397                         if (len == l || s[len] != '=')
 398                                 continue;
 399                         *arg = s + len + 1;
 400                 } else if (len != l)
 401                         continue;
 402                 return tokens[i].opt;
 403         }
 404         return Opt_error;
 405 }
 406
 407 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 408
 409 static int may_context_mount_sb_relabel(u32 sid,
 410                         struct superblock_security_struct *sbsec,
 411                         const struct cred *cred)
 412 {
 413         const struct task_security_struct *tsec = selinux_cred(cred);
 414         int rc;
 415
 416         rc = avc_has_perm(&selinux_state,
 417                           tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 418                           FILESYSTEM__RELABELFROM, NULL);
 419         if (rc)
 420                 return rc;
 421
 422         rc = avc_has_perm(&selinux_state,
 423                           tsec->sid, sid, SECCLASS_FILESYSTEM,
 424                           FILESYSTEM__RELABELTO, NULL);
 425         return rc;
 426 }
 427
 428 static int may_context_mount_inode_relabel(u32 sid,
 429                         struct superblock_security_struct *sbsec,
 430                         const struct cred *cred)
 431 {
 432         const struct task_security_struct *tsec = selinux_cred(cred);
 433         int rc;
 434         rc = avc_has_perm(&selinux_state,
 435                           tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 436                           FILESYSTEM__RELABELFROM, NULL);
 437         if (rc)
 438                 return rc;
 439
 440         rc = avc_has_perm(&selinux_state,
 441                           sid, sbsec->sid, SECCLASS_FILESYSTEM,
 442                           FILESYSTEM__ASSOCIATE, NULL);
 443         return rc;
 444 }
 445
 446 static int selinux_is_genfs_special_handling(struct super_block *sb)
 447 {
 448         /* Special handling. Genfs but also in-core setxattr handler */
 449         return  !strcmp(sb->s_type->name, "sysfs") ||
 450                 !strcmp(sb->s_type->name, "pstore") ||
 451                 !strcmp(sb->s_type->name, "debugfs") ||
 452                 !strcmp(sb->s_type->name, "tracefs") ||
 453                 !strcmp(sb->s_type->name, "rootfs") ||
 454                 (selinux_policycap_cgroupseclabel() &&
 455                  (!strcmp(sb->s_type->name, "cgroup") ||
 456                   !strcmp(sb->s_type->name, "cgroup2")));
 457 }
 458
 459 static int selinux_is_sblabel_mnt(struct super_block *sb)
 460 {
 461         struct superblock_security_struct *sbsec = sb->s_security;
 462
 463         /*
 464          * IMPORTANT: Double-check logic in this function when adding a new
 465          * SECURITY_FS_USE_* definition!
 466          */
 467         BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
 468
 469         switch (sbsec->behavior) {
 470         case SECURITY_FS_USE_XATTR:
 471         case SECURITY_FS_USE_TRANS:
 472         case SECURITY_FS_USE_TASK:
 473         case SECURITY_FS_USE_NATIVE:
 474                 return 1;
 475
 476         case SECURITY_FS_USE_GENFS:
 477                 return selinux_is_genfs_special_handling(sb);
 478
 479         /* Never allow relabeling on context mounts */
 480         case SECURITY_FS_USE_MNTPOINT:
 481         case SECURITY_FS_USE_NONE:
 482         default:
 483                 return 0;
 484         }
 485 }
 486
 487 static int sb_finish_set_opts(struct super_block *sb)
 488 {
 489         struct superblock_security_struct *sbsec = sb->s_security;
 490         struct dentry *root = sb->s_root;
 491         struct inode *root_inode = d_backing_inode(root);
 492         int rc = 0;
 493
 494         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 495                 /* Make sure that the xattr handler exists and that no
 496                    error other than -ENODATA is returned by getxattr on
 497                    the root directory.  -ENODATA is ok, as this may be
 498                    the first boot of the SELinux kernel before we have
 499                    assigned xattr values to the filesystem. */
 500                 if (!(root_inode->i_opflags & IOP_XATTR)) {
 501                         pr_warn("SELinux: (dev %s, type %s) has no "
 502                                "xattr support\n", sb->s_id, sb->s_type->name);
 503                         rc = -EOPNOTSUPP;
 504                         goto out;
 505                 }
 506
 507                 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
 508                 if (rc < 0 && rc != -ENODATA) {
 509                         if (rc == -EOPNOTSUPP)
 510                                 pr_warn("SELinux: (dev %s, type "
 511                                        "%s) has no security xattr handler\n",
 512                                        sb->s_id, sb->s_type->name);
 513                         else
 514                                 pr_warn("SELinux: (dev %s, type "
 515                                        "%s) getxattr errno %d\n", sb->s_id,
 516                                        sb->s_type->name, -rc);
 517                         goto out;
 518                 }
 519         }
 520
 521         sbsec->flags |= SE_SBINITIALIZED;
 522
 523         /*
 524          * Explicitly set or clear SBLABEL_MNT.  It's not sufficient to simply
 525          * leave the flag untouched because sb_clone_mnt_opts might be handing
 526          * us a superblock that needs the flag to be cleared.
 527          */
 528         if (selinux_is_sblabel_mnt(sb))
 529                 sbsec->flags |= SBLABEL_MNT;
 530         else
 531                 sbsec->flags &= ~SBLABEL_MNT;
 532
 533         /* Initialize the root inode. */
 534         rc = inode_doinit_with_dentry(root_inode, root);
 535
 536         /* Initialize any other inodes associated with the superblock, e.g.
 537            inodes created prior to initial policy load or inodes created
 538            during get_sb by a pseudo filesystem that directly
 539            populates itself. */
 540         spin_lock(&sbsec->isec_lock);
 541         while (!list_empty(&sbsec->isec_head)) {
 542                 struct inode_security_struct *isec =
 543                                 list_first_entry(&sbsec->isec_head,
 544                                            struct inode_security_struct, list);
 545                 struct inode *inode = isec->inode;
 546                 list_del_init(&isec->list);
 547                 spin_unlock(&sbsec->isec_lock);
 548                 inode = igrab(inode);
 549                 if (inode) {
 550                         if (!IS_PRIVATE(inode))
 551                                 inode_doinit_with_dentry(inode, NULL);
 552                         iput(inode);
 553                 }
 554                 spin_lock(&sbsec->isec_lock);
 555         }
 556         spin_unlock(&sbsec->isec_lock);
 557 out:
 558         return rc;
 559 }
 560
 561 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 562                       u32 old_sid, u32 new_sid)
 563 {
 564         char mnt_flags = sbsec->flags & SE_MNTMASK;
 565
 566         /* check if the old mount command had the same options */
 567         if (sbsec->flags & SE_SBINITIALIZED)
 568                 if (!(sbsec->flags & flag) ||
 569                     (old_sid != new_sid))
 570                         return 1;
 571
 572         /* check if we were passed the same options twice,
 573          * aka someone passed context=a,context=b
 574          */
 575         if (!(sbsec->flags & SE_SBINITIALIZED))
 576                 if (mnt_flags & flag)
 577                         return 1;
 578         return 0;
 579 }
 580
 581 static int parse_sid(struct super_block *sb, const char *s, u32 *sid)
 582 {
 583         int rc = security_context_str_to_sid(&selinux_state, s,
 584                                              sid, GFP_KERNEL);
 585         if (rc)
 586                 pr_warn("SELinux: security_context_str_to_sid"
 587                        "(%s) failed for (dev %s, type %s) errno=%d\n",
 588                        s, sb->s_id, sb->s_type->name, rc);
 589         return rc;
 590 }
 591
 592 /*
 593  * Allow filesystems with binary mount data to explicitly set mount point
 594  * labeling information.
 595  */
 596 static int selinux_set_mnt_opts(struct super_block *sb,
 597                                 void *mnt_opts,
 598                                 unsigned long kern_flags,
 599                                 unsigned long *set_kern_flags)
 600 {
 601         const struct cred *cred = current_cred();
 602         struct superblock_security_struct *sbsec = sb->s_security;
 603         struct dentry *root = sbsec->sb->s_root;
 604         struct selinux_mnt_opts *opts = mnt_opts;
 605         struct inode_security_struct *root_isec;
 606         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 607         u32 defcontext_sid = 0;
 608         int rc = 0;
 609
 610         mutex_lock(&sbsec->lock);
 611
 612         if (!selinux_initialized(&selinux_state)) {
 613                 if (!opts) {
 614                         /* Defer initialization until selinux_complete_init,
 615                            after the initial policy is loaded and the security
 616                            server is ready to handle calls. */
 617                         goto out;
 618                 }
 619                 rc = -EINVAL;
 620                 pr_warn("SELinux: Unable to set superblock options "
 621                         "before the security server is initialized\n");
 622                 goto out;
 623         }
 624         if (kern_flags && !set_kern_flags) {
 625                 /* Specifying internal flags without providing a place to
 626                  * place the results is not allowed */
 627                 rc = -EINVAL;
 628                 goto out;
 629         }
 630
 631         /*
 632          * Binary mount data FS will come through this function twice.  Once
 633          * from an explicit call and once from the generic calls from the vfs.
 634          * Since the generic VFS calls will not contain any security mount data
 635          * we need to skip the double mount verification.
 636          *
 637          * This does open a hole in which we will not notice if the first
 638          * mount using this sb set explict options and a second mount using
 639          * this sb does not set any security options.  (The first options
 640          * will be used for both mounts)
 641          */
 642         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 643             && !opts)
 644                 goto out;
 645
 646         root_isec = backing_inode_security_novalidate(root);
 647
 648         /*
 649          * parse the mount options, check if they are valid sids.
 650          * also check if someone is trying to mount the same sb more
 651          * than once with different security options.
 652          */
 653         if (opts) {
 654                 if (opts->fscontext) {
 655                         rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
 656                         if (rc)
 657                                 goto out;
 658                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 659                                         fscontext_sid))
 660                                 goto out_double_mount;
 661                         sbsec->flags |= FSCONTEXT_MNT;
 662                 }
 663                 if (opts->context) {
 664                         rc = parse_sid(sb, opts->context, &context_sid);
 665                         if (rc)
 666                                 goto out;
 667                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 668                                         context_sid))
 669                                 goto out_double_mount;
 670                         sbsec->flags |= CONTEXT_MNT;
 671                 }
 672                 if (opts->rootcontext) {
 673                         rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
 674                         if (rc)
 675                                 goto out;
 676                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 677                                         rootcontext_sid))
 678                                 goto out_double_mount;
 679                         sbsec->flags |= ROOTCONTEXT_MNT;
 680                 }
 681                 if (opts->defcontext) {
 682                         rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
 683                         if (rc)
 684                                 goto out;
 685                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 686                                         defcontext_sid))
 687                                 goto out_double_mount;
 688                         sbsec->flags |= DEFCONTEXT_MNT;
 689                 }
 690         }
 691
 692         if (sbsec->flags & SE_SBINITIALIZED) {
 693                 /* previously mounted with options, but not on this attempt? */
 694                 if ((sbsec->flags & SE_MNTMASK) && !opts)
 695                         goto out_double_mount;
 696                 rc = 0;
 697                 goto out;
 698         }
 699
 700         if (strcmp(sb->s_type->name, "proc") == 0)
 701                 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
 702
 703         if (!strcmp(sb->s_type->name, "debugfs") ||
 704             !strcmp(sb->s_type->name, "tracefs") ||
 705             !strcmp(sb->s_type->name, "binder") ||
 706             !strcmp(sb->s_type->name, "bpf") ||
 707             !strcmp(sb->s_type->name, "pstore"))
 708                 sbsec->flags |= SE_SBGENFS;
 709
 710         if (!strcmp(sb->s_type->name, "sysfs") ||
 711             !strcmp(sb->s_type->name, "cgroup") ||
 712             !strcmp(sb->s_type->name, "cgroup2"))
 713                 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
 714
 715         if (!sbsec->behavior) {
 716                 /*
 717                  * Determine the labeling behavior to use for this
 718                  * filesystem type.
 719                  */
 720                 rc = security_fs_use(&selinux_state, sb);
 721                 if (rc) {
 722                         pr_warn("%s: security_fs_use(%s) returned %d\n",
 723                                         __func__, sb->s_type->name, rc);
 724                         goto out;
 725                 }
 726         }
 727
 728         /*
 729          * If this is a user namespace mount and the filesystem type is not
 730          * explicitly whitelisted, then no contexts are allowed on the command
 731          * line and security labels must be ignored.
 732          */
 733         if (sb->s_user_ns != &init_user_ns &&
 734             strcmp(sb->s_type->name, "tmpfs") &&
 735             strcmp(sb->s_type->name, "ramfs") &&
 736             strcmp(sb->s_type->name, "devpts")) {
 737                 if (context_sid || fscontext_sid || rootcontext_sid ||
 738                     defcontext_sid) {
 739                         rc = -EACCES;
 740                         goto out;
 741                 }
 742                 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 743                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 744                         rc = security_transition_sid(&selinux_state,
 745                                                      current_sid(),
 746                                                      current_sid(),
 747                                                      SECCLASS_FILE, NULL,
 748                                                      &sbsec->mntpoint_sid);
 749                         if (rc)
 750                                 goto out;
 751                 }
 752                 goto out_set_opts;
 753         }
 754
 755         /* sets the context of the superblock for the fs being mounted. */
 756         if (fscontext_sid) {
 757                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 758                 if (rc)
 759                         goto out;
 760
 761                 sbsec->sid = fscontext_sid;
 762         }
 763
 764         /*
 765          * Switch to using mount point labeling behavior.
 766          * sets the label used on all file below the mountpoint, and will set
 767          * the superblock context if not already set.
 768          */
 769         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 770                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 771                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 772         }
 773
 774         if (context_sid) {
 775                 if (!fscontext_sid) {
 776                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 777                                                           cred);
 778                         if (rc)
 779                                 goto out;
 780                         sbsec->sid = context_sid;
 781                 } else {
 782                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 783                                                              cred);
 784                         if (rc)
 785                                 goto out;
 786                 }
 787                 if (!rootcontext_sid)
 788                         rootcontext_sid = context_sid;
 789
 790                 sbsec->mntpoint_sid = context_sid;
 791                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 792         }
 793
 794         if (rootcontext_sid) {
 795                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 796                                                      cred);
 797                 if (rc)
 798                         goto out;
 799
 800                 root_isec->sid = rootcontext_sid;
 801                 root_isec->initialized = LABEL_INITIALIZED;
 802         }
 803
 804         if (defcontext_sid) {
 805                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 806                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 807                         rc = -EINVAL;
 808                         pr_warn("SELinux: defcontext option is "
 809                                "invalid for this filesystem type\n");
 810                         goto out;
 811                 }
 812
 813                 if (defcontext_sid != sbsec->def_sid) {
 814                         rc = may_context_mount_inode_relabel(defcontext_sid,
 815                                                              sbsec, cred);
 816                         if (rc)
 817                                 goto out;
 818                 }
 819
 820                 sbsec->def_sid = defcontext_sid;
 821         }
 822
 823 out_set_opts:
 824         rc = sb_finish_set_opts(sb);
 825 out:
 826         mutex_unlock(&sbsec->lock);
 827         return rc;
 828 out_double_mount:
 829         rc = -EINVAL;
 830         pr_warn("SELinux: mount invalid.  Same superblock, different "
 831                "security settings for (dev %s, type %s)\n", sb->s_id,
 832                sb->s_type->name);
 833         goto out;
 834 }
 835
 836 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 837                                     const struct super_block *newsb)
 838 {
 839         struct superblock_security_struct *old = oldsb->s_security;
 840         struct superblock_security_struct *new = newsb->s_security;
 841         char oldflags = old->flags & SE_MNTMASK;
 842         char newflags = new->flags & SE_MNTMASK;
 843
 844         if (oldflags != newflags)
 845                 goto mismatch;
 846         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 847                 goto mismatch;
 848         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 849                 goto mismatch;
 850         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 851                 goto mismatch;
 852         if (oldflags & ROOTCONTEXT_MNT) {
 853                 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
 854                 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
 855                 if (oldroot->sid != newroot->sid)
 856                         goto mismatch;
 857         }
 858         return 0;
 859 mismatch:
 860         pr_warn("SELinux: mount invalid.  Same superblock, "
 861                             "different security settings for (dev %s, "
 862                             "type %s)\n", newsb->s_id, newsb->s_type->name);
 863         return -EBUSY;
 864 }
 865
 866 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 867                                         struct super_block *newsb,
 868                                         unsigned long kern_flags,
 869                                         unsigned long *set_kern_flags)
 870 {
 871         int rc = 0;
 872         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 873         struct superblock_security_struct *newsbsec = newsb->s_security;
 874
 875         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 876         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 877         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 878
 879         /*
 880          * if the parent was able to be mounted it clearly had no special lsm
 881          * mount options.  thus we can safely deal with this superblock later
 882          */
 883         if (!selinux_initialized(&selinux_state))
 884                 return 0;
 885
 886         /*
 887          * Specifying internal flags without providing a place to
 888          * place the results is not allowed.
 889          */
 890         if (kern_flags && !set_kern_flags)
 891                 return -EINVAL;
 892
 893         /* how can we clone if the old one wasn't set up?? */
 894         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 895
 896         /* if fs is reusing a sb, make sure that the contexts match */
 897         if (newsbsec->flags & SE_SBINITIALIZED) {
 898                 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
 899                         *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 900                 return selinux_cmp_sb_context(oldsb, newsb);
 901         }
 902
 903         mutex_lock(&newsbsec->lock);
 904
 905         newsbsec->flags = oldsbsec->flags;
 906
 907         newsbsec->sid = oldsbsec->sid;
 908         newsbsec->def_sid = oldsbsec->def_sid;
 909         newsbsec->behavior = oldsbsec->behavior;
 910
 911         if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
 912                 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
 913                 rc = security_fs_use(&selinux_state, newsb);
 914                 if (rc)
 915                         goto out;
 916         }
 917
 918         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
 919                 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
 920                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 921         }
 922
 923         if (set_context) {
 924                 u32 sid = oldsbsec->mntpoint_sid;
 925
 926                 if (!set_fscontext)
 927                         newsbsec->sid = sid;
 928                 if (!set_rootcontext) {
 929                         struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 930                         newisec->sid = sid;
 931                 }
 932                 newsbsec->mntpoint_sid = sid;
 933         }
 934         if (set_rootcontext) {
 935                 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
 936                 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
 937
 938                 newisec->sid = oldisec->sid;
 939         }
 940
 941         sb_finish_set_opts(newsb);
 942 out:
 943         mutex_unlock(&newsbsec->lock);
 944         return rc;
 945 }
 946
 947 static int selinux_add_opt(int token, const char *s, void **mnt_opts)
 948 {
 949         struct selinux_mnt_opts *opts = *mnt_opts;
 950
 951         if (token == Opt_seclabel)      /* eaten and completely ignored */
 952                 return 0;
 953
 954         if (!opts) {
 955                 opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
 956                 if (!opts)
 957                         return -ENOMEM;
 958                 *mnt_opts = opts;
 959         }
 960         if (!s)
 961                 return -ENOMEM;
 962         switch (token) {
 963         case Opt_context:
 964                 if (opts->context || opts->defcontext)
 965                         goto Einval;
 966                 opts->context = s;
 967                 break;
 968         case Opt_fscontext:
 969                 if (opts->fscontext)
 970                         goto Einval;
 971                 opts->fscontext = s;
 972                 break;
 973         case Opt_rootcontext:
 974                 if (opts->rootcontext)
 975                         goto Einval;
 976                 opts->rootcontext = s;
 977                 break;
 978         case Opt_defcontext:
 979                 if (opts->context || opts->defcontext)
 980                         goto Einval;
 981                 opts->defcontext = s;
 982                 break;
 983         }
 984         return 0;
 985 Einval:
 986         pr_warn(SEL_MOUNT_FAIL_MSG);
 987         return -EINVAL;
 988 }
 989
 990 static int selinux_add_mnt_opt(const char *option, const char *val, int len,
 991                                void **mnt_opts)
 992 {
 993         int token = Opt_error;
 994         int rc, i;
 995
 996         for (i = 0; i < ARRAY_SIZE(tokens); i++) {
 997                 if (strcmp(option, tokens[i].name) == 0) {
 998                         token = tokens[i].opt;
 999                         break;
1000                 }
1001         }
1002
1003         if (token == Opt_error)
1004                 return -EINVAL;
1005
1006         if (token != Opt_seclabel) {
1007                 val = kmemdup_nul(val, len, GFP_KERNEL);
1008                 if (!val) {
1009                         rc = -ENOMEM;
1010                         goto free_opt;
1011                 }
1012         }
1013         rc = selinux_add_opt(token, val, mnt_opts);
1014         if (unlikely(rc)) {
1015                 kfree(val);
1016                 goto free_opt;
1017         }
1018         return rc;
1019
1020 free_opt:
1021         if (*mnt_opts) {
1022                 selinux_free_mnt_opts(*mnt_opts);
1023                 *mnt_opts = NULL;
1024         }
1025         return rc;
1026 }
1027
1028 static int show_sid(struct seq_file *m, u32 sid)
1029 {
1030         char *context = NULL;
1031         u32 len;
1032         int rc;
1033
1034         rc = security_sid_to_context(&selinux_state, sid,
1035                                              &context, &len);
1036         if (!rc) {
1037                 bool has_comma = context && strchr(context, ',');
1038
1039                 seq_putc(m, '=');
1040                 if (has_comma)
1041                         seq_putc(m, '\"');
1042                 seq_escape(m, context, "\"\n\\");
1043                 if (has_comma)
1044                         seq_putc(m, '\"');
1045         }
1046         kfree(context);
1047         return rc;
1048 }
1049
1050 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1051 {
1052         struct superblock_security_struct *sbsec = sb->s_security;
1053         int rc;
1054
1055         if (!(sbsec->flags & SE_SBINITIALIZED))
1056                 return 0;
1057
1058         if (!selinux_initialized(&selinux_state))
1059                 return 0;
1060
1061         if (sbsec->flags & FSCONTEXT_MNT) {
1062                 seq_putc(m, ',');
1063                 seq_puts(m, FSCONTEXT_STR);
1064                 rc = show_sid(m, sbsec->sid);
1065                 if (rc)
1066                         return rc;
1067         }
1068         if (sbsec->flags & CONTEXT_MNT) {
1069                 seq_putc(m, ',');
1070                 seq_puts(m, CONTEXT_STR);
1071                 rc = show_sid(m, sbsec->mntpoint_sid);
1072                 if (rc)
1073                         return rc;
1074         }
1075         if (sbsec->flags & DEFCONTEXT_MNT) {
1076                 seq_putc(m, ',');
1077                 seq_puts(m, DEFCONTEXT_STR);
1078                 rc = show_sid(m, sbsec->def_sid);
1079                 if (rc)
1080                         return rc;
1081         }
1082         if (sbsec->flags & ROOTCONTEXT_MNT) {
1083                 struct dentry *root = sbsec->sb->s_root;
1084                 struct inode_security_struct *isec = backing_inode_security(root);
1085                 seq_putc(m, ',');
1086                 seq_puts(m, ROOTCONTEXT_STR);
1087                 rc = show_sid(m, isec->sid);
1088                 if (rc)
1089                         return rc;
1090         }
1091         if (sbsec->flags & SBLABEL_MNT) {
1092                 seq_putc(m, ',');
1093                 seq_puts(m, SECLABEL_STR);
1094         }
1095         return 0;
1096 }
1097
1098 static inline u16 inode_mode_to_security_class(umode_t mode)
1099 {
1100         switch (mode & S_IFMT) {
1101         case S_IFSOCK:
1102                 return SECCLASS_SOCK_FILE;
1103         case S_IFLNK:
1104                 return SECCLASS_LNK_FILE;
1105         case S_IFREG:
1106                 return SECCLASS_FILE;
1107         case S_IFBLK:
1108                 return SECCLASS_BLK_FILE;
1109         case S_IFDIR:
1110                 return SECCLASS_DIR;
1111         case S_IFCHR:
1112                 return SECCLASS_CHR_FILE;
1113         case S_IFIFO:
1114                 return SECCLASS_FIFO_FILE;
1115
1116         }
1117
1118         return SECCLASS_FILE;
1119 }
1120
1121 static inline int default_protocol_stream(int protocol)
1122 {
1123         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1124 }
1125
1126 static inline int default_protocol_dgram(int protocol)
1127 {
1128         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1129 }
1130
1131 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1132 {
1133         int extsockclass = selinux_policycap_extsockclass();
1134
1135         switch (family) {
1136         case PF_UNIX:
1137                 switch (type) {
1138                 case SOCK_STREAM:
1139                 case SOCK_SEQPACKET:
1140                         return SECCLASS_UNIX_STREAM_SOCKET;
1141                 case SOCK_DGRAM:
1142                 case SOCK_RAW:
1143                         return SECCLASS_UNIX_DGRAM_SOCKET;
1144                 }
1145                 break;
1146         case PF_INET:
1147         case PF_INET6:
1148                 switch (type) {
1149                 case SOCK_STREAM:
1150                 case SOCK_SEQPACKET:
1151                         if (default_protocol_stream(protocol))
1152                                 return SECCLASS_TCP_SOCKET;
1153                         else if (extsockclass && protocol == IPPROTO_SCTP)
1154                                 return SECCLASS_SCTP_SOCKET;
1155                         else
1156                                 return SECCLASS_RAWIP_SOCKET;
1157                 case SOCK_DGRAM:
1158                         if (default_protocol_dgram(protocol))
1159                                 return SECCLASS_UDP_SOCKET;
1160                         else if (extsockclass && (protocol == IPPROTO_ICMP ||
1161                                                   protocol == IPPROTO_ICMPV6))
1162                                 return SECCLASS_ICMP_SOCKET;
1163                         else
1164                                 return SECCLASS_RAWIP_SOCKET;
1165                 case SOCK_DCCP:
1166                         return SECCLASS_DCCP_SOCKET;
1167                 default:
1168                         return SECCLASS_RAWIP_SOCKET;
1169                 }
1170                 break;
1171         case PF_NETLINK:
1172                 switch (protocol) {
1173                 case NETLINK_ROUTE:
1174                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1175                 case NETLINK_SOCK_DIAG:
1176                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1177                 case NETLINK_NFLOG:
1178                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1179                 case NETLINK_XFRM:
1180                         return SECCLASS_NETLINK_XFRM_SOCKET;
1181                 case NETLINK_SELINUX:
1182                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1183                 case NETLINK_ISCSI:
1184                         return SECCLASS_NETLINK_ISCSI_SOCKET;
1185                 case NETLINK_AUDIT:
1186                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1187                 case NETLINK_FIB_LOOKUP:
1188                         return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1189                 case NETLINK_CONNECTOR:
1190                         return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1191                 case NETLINK_NETFILTER:
1192                         return SECCLASS_NETLINK_NETFILTER_SOCKET;
1193                 case NETLINK_DNRTMSG:
1194                         return SECCLASS_NETLINK_DNRT_SOCKET;
1195                 case NETLINK_KOBJECT_UEVENT:
1196                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1197                 case NETLINK_GENERIC:
1198                         return SECCLASS_NETLINK_GENERIC_SOCKET;
1199                 case NETLINK_SCSITRANSPORT:
1200                         return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1201                 case NETLINK_RDMA:
1202                         return SECCLASS_NETLINK_RDMA_SOCKET;
1203                 case NETLINK_CRYPTO:
1204                         return SECCLASS_NETLINK_CRYPTO_SOCKET;
1205                 default:
1206                         return SECCLASS_NETLINK_SOCKET;
1207                 }
1208         case PF_PACKET:
1209                 return SECCLASS_PACKET_SOCKET;
1210         case PF_KEY:
1211                 return SECCLASS_KEY_SOCKET;
1212         case PF_APPLETALK:
1213                 return SECCLASS_APPLETALK_SOCKET;
1214         }
1215
1216         if (extsockclass) {
1217                 switch (family) {
1218                 case PF_AX25:
1219                         return SECCLASS_AX25_SOCKET;
1220                 case PF_IPX:
1221                         return SECCLASS_IPX_SOCKET;
1222                 case PF_NETROM:
1223                         return SECCLASS_NETROM_SOCKET;
1224                 case PF_ATMPVC:
1225                         return SECCLASS_ATMPVC_SOCKET;
1226                 case PF_X25:
1227                         return SECCLASS_X25_SOCKET;
1228                 case PF_ROSE:
1229                         return SECCLASS_ROSE_SOCKET;
1230                 case PF_DECnet:
1231                         return SECCLASS_DECNET_SOCKET;
1232                 case PF_ATMSVC:
1233                         return SECCLASS_ATMSVC_SOCKET;
1234                 case PF_RDS:
1235                         return SECCLASS_RDS_SOCKET;
1236                 case PF_IRDA:
1237                         return SECCLASS_IRDA_SOCKET;
1238                 case PF_PPPOX:
1239                         return SECCLASS_PPPOX_SOCKET;
1240                 case PF_LLC:
1241                         return SECCLASS_LLC_SOCKET;
1242                 case PF_CAN:
1243                         return SECCLASS_CAN_SOCKET;
1244                 case PF_TIPC:
1245                         return SECCLASS_TIPC_SOCKET;
1246                 case PF_BLUETOOTH:
1247                         return SECCLASS_BLUETOOTH_SOCKET;
1248                 case PF_IUCV:
1249                         return SECCLASS_IUCV_SOCKET;
1250                 case PF_RXRPC:
1251                         return SECCLASS_RXRPC_SOCKET;
1252                 case PF_ISDN:
1253                         return SECCLASS_ISDN_SOCKET;
1254                 case PF_PHONET:
1255                         return SECCLASS_PHONET_SOCKET;
1256                 case PF_IEEE802154:
1257                         return SECCLASS_IEEE802154_SOCKET;
1258                 case PF_CAIF:
1259                         return SECCLASS_CAIF_SOCKET;
1260                 case PF_ALG:
1261                         return SECCLASS_ALG_SOCKET;
1262                 case PF_NFC:
1263                         return SECCLASS_NFC_SOCKET;
1264                 case PF_VSOCK:
1265                         return SECCLASS_VSOCK_SOCKET;
1266                 case PF_KCM:
1267                         return SECCLASS_KCM_SOCKET;
1268                 case PF_QIPCRTR:
1269                         return SECCLASS_QIPCRTR_SOCKET;
1270                 case PF_SMC:
1271                         return SECCLASS_SMC_SOCKET;
1272                 case PF_XDP:
1273                         return SECCLASS_XDP_SOCKET;
1274 #if PF_MAX > 45
1275 #error New address family defined, please update this function.
1276 #endif
1277                 }
1278         }
1279
1280         return SECCLASS_SOCKET;
1281 }
1282
1283 static int selinux_genfs_get_sid(struct dentry *dentry,
1284                                  u16 tclass,
1285                                  u16 flags,
1286                                  u32 *sid)
1287 {
1288         int rc;
1289         struct super_block *sb = dentry->d_sb;
1290         char *buffer, *path;
1291
1292         buffer = (char *)__get_free_page(GFP_KERNEL);
1293         if (!buffer)
1294                 return -ENOMEM;
1295
1296         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1297         if (IS_ERR(path))
1298                 rc = PTR_ERR(path);
1299         else {
1300                 if (flags & SE_SBPROC) {
1301                         /* each process gets a /proc/PID/ entry. Strip off the
1302                          * PID part to get a valid selinux labeling.
1303                          * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1304                         while (path[1] >= '0' && path[1] <= '9') {
1305                                 path[1] = '/';
1306                                 path++;
1307                         }
1308                 }
1309                 rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1310                                         path, tclass, sid);
1311                 if (rc == -ENOENT) {
1312                         /* No match in policy, mark as unlabeled. */
1313                         *sid = SECINITSID_UNLABELED;
1314                         rc = 0;
1315                 }
1316         }
1317         free_page((unsigned long)buffer);
1318         return rc;
1319 }
1320
1321 static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1322                                   u32 def_sid, u32 *sid)
1323 {
1324 #define INITCONTEXTLEN 255
1325         char *context;
1326         unsigned int len;
1327         int rc;
1328
1329         len = INITCONTEXTLEN;
1330         context = kmalloc(len + 1, GFP_NOFS);
1331         if (!context)
1332                 return -ENOMEM;
1333
1334         context[len] = '\0';
1335         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1336         if (rc == -ERANGE) {
1337                 kfree(context);
1338
1339                 /* Need a larger buffer.  Query for the right size. */
1340                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1341                 if (rc < 0)
1342                         return rc;
1343
1344                 len = rc;
1345                 context = kmalloc(len + 1, GFP_NOFS);
1346                 if (!context)
1347                         return -ENOMEM;
1348
1349                 context[len] = '\0';
1350                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1351                                     context, len);
1352         }
1353         if (rc < 0) {
1354                 kfree(context);
1355                 if (rc != -ENODATA) {
1356                         pr_warn("SELinux: %s:  getxattr returned %d for dev=%s ino=%ld\n",
1357                                 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1358                         return rc;
1359                 }
1360                 *sid = def_sid;
1361                 return 0;
1362         }
1363
1364         rc = security_context_to_sid_default(&selinux_state, context, rc, sid,
1365                                              def_sid, GFP_NOFS);
1366         if (rc) {
1367                 char *dev = inode->i_sb->s_id;
1368                 unsigned long ino = inode->i_ino;
1369
1370                 if (rc == -EINVAL) {
1371                         pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s.  This indicates you may need to relabel the inode or the filesystem in question.\n",
1372                                               ino, dev, context);
1373                 } else {
1374                         pr_warn("SELinux: %s:  context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1375                                 __func__, context, -rc, dev, ino);
1376                 }
1377         }
1378         kfree(context);
1379         return 0;
1380 }
1381
1382 /* The inode's security attributes must be initialized before first use. */
1383 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1384 {
1385         struct superblock_security_struct *sbsec = NULL;
1386         struct inode_security_struct *isec = selinux_inode(inode);
1387         u32 task_sid, sid = 0;
1388         u16 sclass;
1389         struct dentry *dentry;
1390         int rc = 0;
1391
1392         if (isec->initialized == LABEL_INITIALIZED)
1393                 return 0;
1394
1395         spin_lock(&isec->lock);
1396         if (isec->initialized == LABEL_INITIALIZED)
1397                 goto out_unlock;
1398
1399         if (isec->sclass == SECCLASS_FILE)
1400                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1401
1402         sbsec = inode->i_sb->s_security;
1403         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1404                 /* Defer initialization until selinux_complete_init,
1405                    after the initial policy is loaded and the security
1406                    server is ready to handle calls. */
1407                 spin_lock(&sbsec->isec_lock);
1408                 if (list_empty(&isec->list))
1409                         list_add(&isec->list, &sbsec->isec_head);
1410                 spin_unlock(&sbsec->isec_lock);
1411                 goto out_unlock;
1412         }
1413
1414         sclass = isec->sclass;
1415         task_sid = isec->task_sid;
1416         sid = isec->sid;
1417         isec->initialized = LABEL_PENDING;
1418         spin_unlock(&isec->lock);
1419
1420         switch (sbsec->behavior) {
1421         case SECURITY_FS_USE_NATIVE:
1422                 break;
1423         case SECURITY_FS_USE_XATTR:
1424                 if (!(inode->i_opflags & IOP_XATTR)) {
1425                         sid = sbsec->def_sid;
1426                         break;
1427                 }
1428                 /* Need a dentry, since the xattr API requires one.
1429                    Life would be simpler if we could just pass the inode. */
1430                 if (opt_dentry) {
1431                         /* Called from d_instantiate or d_splice_alias. */
1432                         dentry = dget(opt_dentry);
1433                 } else {
1434                         /*
1435                          * Called from selinux_complete_init, try to find a dentry.
1436                          * Some filesystems really want a connected one, so try
1437                          * that first.  We could split SECURITY_FS_USE_XATTR in
1438                          * two, depending upon that...
1439                          */
1440                         dentry = d_find_alias(inode);
1441                         if (!dentry)
1442                                 dentry = d_find_any_alias(inode);
1443                 }
1444                 if (!dentry) {
1445                         /*
1446                          * this is can be hit on boot when a file is accessed
1447                          * before the policy is loaded.  When we load policy we
1448                          * may find inodes that have no dentry on the
1449                          * sbsec->isec_head list.  No reason to complain as these
1450                          * will get fixed up the next time we go through
1451                          * inode_doinit with a dentry, before these inodes could
1452                          * be used again by userspace.
1453                          */
1454                         goto out;
1455                 }
1456
1457                 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1458                                             &sid);
1459                 dput(dentry);
1460                 if (rc)
1461                         goto out;
1462                 break;
1463         case SECURITY_FS_USE_TASK:
1464                 sid = task_sid;
1465                 break;
1466         case SECURITY_FS_USE_TRANS:
1467                 /* Default to the fs SID. */
1468                 sid = sbsec->sid;
1469
1470                 /* Try to obtain a transition SID. */
1471                 rc = security_transition_sid(&selinux_state, task_sid, sid,
1472                                              sclass, NULL, &sid);
1473                 if (rc)
1474                         goto out;
1475                 break;
1476         case SECURITY_FS_USE_MNTPOINT:
1477                 sid = sbsec->mntpoint_sid;
1478                 break;
1479         default:
1480                 /* Default to the fs superblock SID. */
1481                 sid = sbsec->sid;
1482
1483                 if ((sbsec->flags & SE_SBGENFS) &&
1484                      (!S_ISLNK(inode->i_mode) ||
1485                       selinux_policycap_genfs_seclabel_symlinks())) {
1486                         /* We must have a dentry to determine the label on
1487                          * procfs inodes */
1488                         if (opt_dentry) {
1489                                 /* Called from d_instantiate or
1490                                  * d_splice_alias. */
1491                                 dentry = dget(opt_dentry);
1492                         } else {
1493                                 /* Called from selinux_complete_init, try to
1494                                  * find a dentry.  Some filesystems really want
1495                                  * a connected one, so try that first.
1496                                  */
1497                                 dentry = d_find_alias(inode);
1498                                 if (!dentry)
1499                                         dentry = d_find_any_alias(inode);
1500                         }
1501                         /*
1502                          * This can be hit on boot when a file is accessed
1503                          * before the policy is loaded.  When we load policy we
1504                          * may find inodes that have no dentry on the
1505                          * sbsec->isec_head list.  No reason to complain as
1506                          * these will get fixed up the next time we go through
1507                          * inode_doinit() with a dentry, before these inodes
1508                          * could be used again by userspace.
1509                          */
1510                         if (!dentry)
1511                                 goto out;
1512                         rc = selinux_genfs_get_sid(dentry, sclass,
1513                                                    sbsec->flags, &sid);
1514                         if (rc) {
1515                                 dput(dentry);
1516                                 goto out;
1517                         }
1518
1519                         if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1520                             (inode->i_opflags & IOP_XATTR)) {
1521                                 rc = inode_doinit_use_xattr(inode, dentry,
1522                                                             sid, &sid);
1523                                 if (rc) {
1524                                         dput(dentry);
1525                                         goto out;
1526                                 }
1527                         }
1528                         dput(dentry);
1529                 }
1530                 break;
1531         }
1532
1533 out:
1534         spin_lock(&isec->lock);
1535         if (isec->initialized == LABEL_PENDING) {
1536                 if (!sid || rc) {
1537                         isec->initialized = LABEL_INVALID;
1538                         goto out_unlock;
1539                 }
1540
1541                 isec->initialized = LABEL_INITIALIZED;
1542                 isec->sid = sid;
1543         }
1544
1545 out_unlock:
1546         spin_unlock(&isec->lock);
1547         return rc;
1548 }
1549
1550 /* Convert a Linux signal to an access vector. */
1551 static inline u32 signal_to_av(int sig)
1552 {
1553         u32 perm = 0;
1554
1555         switch (sig) {
1556         case SIGCHLD:
1557                 /* Commonly granted from child to parent. */
1558                 perm = PROCESS__SIGCHLD;
1559                 break;
1560         case SIGKILL:
1561                 /* Cannot be caught or ignored */
1562                 perm = PROCESS__SIGKILL;
1563                 break;
1564         case SIGSTOP:
1565                 /* Cannot be caught or ignored */
1566                 perm = PROCESS__SIGSTOP;
1567                 break;
1568         default:
1569                 /* All other signals. */
1570                 perm = PROCESS__SIGNAL;
1571                 break;
1572         }
1573
1574         return perm;
1575 }
1576
1577 #if CAP_LAST_CAP > 63
1578 #error Fix SELinux to handle capabilities > 63.
1579 #endif
1580
1581 /* Check whether a task is allowed to use a capability. */
1582 static int cred_has_capability(const struct cred *cred,
1583                                int cap, unsigned int opts, bool initns)
1584 {
1585         struct common_audit_data ad;
1586         struct av_decision avd;
1587         u16 sclass;
1588         u32 sid = cred_sid(cred);
1589         u32 av = CAP_TO_MASK(cap);
1590         int rc;
1591
1592         ad.type = LSM_AUDIT_DATA_CAP;
1593         ad.u.cap = cap;
1594
1595         switch (CAP_TO_INDEX(cap)) {
1596         case 0:
1597                 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1598                 break;
1599         case 1:
1600                 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1601                 break;
1602         default:
1603                 pr_err("SELinux:  out of range capability %d\n", cap);
1604                 BUG();
1605                 return -EINVAL;
1606         }
1607
1608         rc = avc_has_perm_noaudit(&selinux_state,
1609                                   sid, sid, sclass, av, 0, &avd);
1610         if (!(opts & CAP_OPT_NOAUDIT)) {
1611                 int rc2 = avc_audit(&selinux_state,
1612                                     sid, sid, sclass, av, &avd, rc, &ad, 0);
1613                 if (rc2)
1614                         return rc2;
1615         }
1616         return rc;
1617 }
1618
1619 /* Check whether a task has a particular permission to an inode.
1620    The 'adp' parameter is optional and allows other audit
1621    data to be passed (e.g. the dentry). */
1622 static int inode_has_perm(const struct cred *cred,
1623                           struct inode *inode,
1624                           u32 perms,
1625                           struct common_audit_data *adp)
1626 {
1627         struct inode_security_struct *isec;
1628         u32 sid;
1629
1630         validate_creds(cred);
1631
1632         if (unlikely(IS_PRIVATE(inode)))
1633                 return 0;
1634
1635         sid = cred_sid(cred);
1636         isec = selinux_inode(inode);
1637
1638         return avc_has_perm(&selinux_state,
1639                             sid, isec->sid, isec->sclass, perms, adp);
1640 }
1641
1642 /* Same as inode_has_perm, but pass explicit audit data containing
1643    the dentry to help the auditing code to more easily generate the
1644    pathname if needed. */
1645 static inline int dentry_has_perm(const struct cred *cred,
1646                                   struct dentry *dentry,
1647                                   u32 av)
1648 {
1649         struct inode *inode = d_backing_inode(dentry);
1650         struct common_audit_data ad;
1651
1652         ad.type = LSM_AUDIT_DATA_DENTRY;
1653         ad.u.dentry = dentry;
1654         __inode_security_revalidate(inode, dentry, true);
1655         return inode_has_perm(cred, inode, av, &ad);
1656 }
1657
1658 /* Same as inode_has_perm, but pass explicit audit data containing
1659    the path to help the auditing code to more easily generate the
1660    pathname if needed. */
1661 static inline int path_has_perm(const struct cred *cred,
1662                                 const struct path *path,
1663                                 u32 av)
1664 {
1665         struct inode *inode = d_backing_inode(path->dentry);
1666         struct common_audit_data ad;
1667
1668         ad.type = LSM_AUDIT_DATA_PATH;
1669         ad.u.path = *path;
1670         __inode_security_revalidate(inode, path->dentry, true);
1671         return inode_has_perm(cred, inode, av, &ad);
1672 }
1673
1674 /* Same as path_has_perm, but uses the inode from the file struct. */
1675 static inline int file_path_has_perm(const struct cred *cred,
1676                                      struct file *file,
1677                                      u32 av)
1678 {
1679         struct common_audit_data ad;
1680
1681         ad.type = LSM_AUDIT_DATA_FILE;
1682         ad.u.file = file;
1683         return inode_has_perm(cred, file_inode(file), av, &ad);
1684 }
1685
1686 #ifdef CONFIG_BPF_SYSCALL
1687 static int bpf_fd_pass(struct file *file, u32 sid);
1688 #endif
1689
1690 /* Check whether a task can use an open file descriptor to
1691    access an inode in a given way.  Check access to the
1692    descriptor itself, and then use dentry_has_perm to
1693    check a particular permission to the file.
1694    Access to the descriptor is implicitly granted if it
1695    has the same SID as the process.  If av is zero, then
1696    access to the file is not checked, e.g. for cases
1697    where only the descriptor is affected like seek. */
1698 static int file_has_perm(const struct cred *cred,
1699                          struct file *file,
1700                          u32 av)
1701 {
1702         struct file_security_struct *fsec = selinux_file(file);
1703         struct inode *inode = file_inode(file);
1704         struct common_audit_data ad;
1705         u32 sid = cred_sid(cred);
1706         int rc;
1707
1708         ad.type = LSM_AUDIT_DATA_FILE;
1709         ad.u.file = file;
1710
1711         if (sid != fsec->sid) {
1712                 rc = avc_has_perm(&selinux_state,
1713                                   sid, fsec->sid,
1714                                   SECCLASS_FD,
1715                                   FD__USE,
1716                                   &ad);
1717                 if (rc)
1718                         goto out;
1719         }
1720
1721 #ifdef CONFIG_BPF_SYSCALL
1722         rc = bpf_fd_pass(file, cred_sid(cred));
1723         if (rc)
1724                 return rc;
1725 #endif
1726
1727         /* av is zero if only checking access to the descriptor. */
1728         rc = 0;
1729         if (av)
1730                 rc = inode_has_perm(cred, inode, av, &ad);
1731
1732 out:
1733         return rc;
1734 }
1735
1736 /*
1737  * Determine the label for an inode that might be unioned.
1738  */
1739 static int
1740 selinux_determine_inode_label(const struct task_security_struct *tsec,
1741                                  struct inode *dir,
1742                                  const struct qstr *name, u16 tclass,
1743                                  u32 *_new_isid)
1744 {
1745         const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1746
1747         if ((sbsec->flags & SE_SBINITIALIZED) &&
1748             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1749                 *_new_isid = sbsec->mntpoint_sid;
1750         } else if ((sbsec->flags & SBLABEL_MNT) &&
1751                    tsec->create_sid) {
1752                 *_new_isid = tsec->create_sid;
1753         } else {
1754                 const struct inode_security_struct *dsec = inode_security(dir);
1755                 return security_transition_sid(&selinux_state, tsec->sid,
1756                                                dsec->sid, tclass,
1757                                                name, _new_isid);
1758         }
1759
1760         return 0;
1761 }
1762
1763 /* Check whether a task can create a file. */
1764 static int may_create(struct inode *dir,
1765                       struct dentry *dentry,
1766                       u16 tclass)
1767 {
1768         const struct task_security_struct *tsec = selinux_cred(current_cred());
1769         struct inode_security_struct *dsec;
1770         struct superblock_security_struct *sbsec;
1771         u32 sid, newsid;
1772         struct common_audit_data ad;
1773         int rc;
1774
1775         dsec = inode_security(dir);
1776         sbsec = dir->i_sb->s_security;
1777
1778         sid = tsec->sid;
1779
1780         ad.type = LSM_AUDIT_DATA_DENTRY;
1781         ad.u.dentry = dentry;
1782
1783         rc = avc_has_perm(&selinux_state,
1784                           sid, dsec->sid, SECCLASS_DIR,
1785                           DIR__ADD_NAME | DIR__SEARCH,
1786                           &ad);
1787         if (rc)
1788                 return rc;
1789
1790         rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1791                                            &newsid);
1792         if (rc)
1793                 return rc;
1794
1795         rc = avc_has_perm(&selinux_state,
1796                           sid, newsid, tclass, FILE__CREATE, &ad);
1797         if (rc)
1798                 return rc;
1799
1800         return avc_has_perm(&selinux_state,
1801                             newsid, sbsec->sid,
1802                             SECCLASS_FILESYSTEM,
1803                             FILESYSTEM__ASSOCIATE, &ad);
1804 }
1805
1806 #define MAY_LINK        0
1807 #define MAY_UNLINK      1
1808 #define MAY_RMDIR       2
1809
1810 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1811 static int may_link(struct inode *dir,
1812                     struct dentry *dentry,
1813                     int kind)
1814
1815 {
1816         struct inode_security_struct *dsec, *isec;
1817         struct common_audit_data ad;
1818         u32 sid = current_sid();
1819         u32 av;
1820         int rc;
1821
1822         dsec = inode_security(dir);
1823         isec = backing_inode_security(dentry);
1824
1825         ad.type = LSM_AUDIT_DATA_DENTRY;
1826         ad.u.dentry = dentry;
1827
1828         av = DIR__SEARCH;
1829         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1830         rc = avc_has_perm(&selinux_state,
1831                           sid, dsec->sid, SECCLASS_DIR, av, &ad);
1832         if (rc)
1833                 return rc;
1834
1835         switch (kind) {
1836         case MAY_LINK:
1837                 av = FILE__LINK;
1838                 break;
1839         case MAY_UNLINK:
1840                 av = FILE__UNLINK;
1841                 break;
1842         case MAY_RMDIR:
1843                 av = DIR__RMDIR;
1844                 break;
1845         default:
1846                 pr_warn("SELinux: %s:  unrecognized kind %d\n",
1847                         __func__, kind);
1848                 return 0;
1849         }
1850
1851         rc = avc_has_perm(&selinux_state,
1852                           sid, isec->sid, isec->sclass, av, &ad);
1853         return rc;
1854 }
1855
1856 static inline int may_rename(struct inode *old_dir,
1857                              struct dentry *old_dentry,
1858                              struct inode *new_dir,
1859                              struct dentry *new_dentry)
1860 {
1861         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1862         struct common_audit_data ad;
1863         u32 sid = current_sid();
1864         u32 av;
1865         int old_is_dir, new_is_dir;
1866         int rc;
1867
1868         old_dsec = inode_security(old_dir);
1869         old_isec = backing_inode_security(old_dentry);
1870         old_is_dir = d_is_dir(old_dentry);
1871         new_dsec = inode_security(new_dir);
1872
1873         ad.type = LSM_AUDIT_DATA_DENTRY;
1874
1875         ad.u.dentry = old_dentry;
1876         rc = avc_has_perm(&selinux_state,
1877                           sid, old_dsec->sid, SECCLASS_DIR,
1878                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1879         if (rc)
1880                 return rc;
1881         rc = avc_has_perm(&selinux_state,
1882                           sid, old_isec->sid,
1883                           old_isec->sclass, FILE__RENAME, &ad);
1884         if (rc)
1885                 return rc;
1886         if (old_is_dir && new_dir != old_dir) {
1887                 rc = avc_has_perm(&selinux_state,
1888                                   sid, old_isec->sid,
1889                                   old_isec->sclass, DIR__REPARENT, &ad);
1890                 if (rc)
1891                         return rc;
1892         }
1893
1894         ad.u.dentry = new_dentry;
1895         av = DIR__ADD_NAME | DIR__SEARCH;
1896         if (d_is_positive(new_dentry))
1897                 av |= DIR__REMOVE_NAME;
1898         rc = avc_has_perm(&selinux_state,
1899                           sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1900         if (rc)
1901                 return rc;
1902         if (d_is_positive(new_dentry)) {
1903                 new_isec = backing_inode_security(new_dentry);
1904                 new_is_dir = d_is_dir(new_dentry);
1905                 rc = avc_has_perm(&selinux_state,
1906                                   sid, new_isec->sid,
1907                                   new_isec->sclass,
1908                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1909                 if (rc)
1910                         return rc;
1911         }
1912
1913         return 0;
1914 }
1915
1916 /* Check whether a task can perform a filesystem operation. */
1917 static int superblock_has_perm(const struct cred *cred,
1918                                struct super_block *sb,
1919                                u32 perms,
1920                                struct common_audit_data *ad)
1921 {
1922         struct superblock_security_struct *sbsec;
1923         u32 sid = cred_sid(cred);
1924
1925         sbsec = sb->s_security;
1926         return avc_has_perm(&selinux_state,
1927                             sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1928 }
1929
1930 /* Convert a Linux mode and permission mask to an access vector. */
1931 static inline u32 file_mask_to_av(int mode, int mask)
1932 {
1933         u32 av = 0;
1934
1935         if (!S_ISDIR(mode)) {
1936                 if (mask & MAY_EXEC)
1937                         av |= FILE__EXECUTE;
1938                 if (mask & MAY_READ)
1939                         av |= FILE__READ;
1940
1941                 if (mask & MAY_APPEND)
1942                         av |= FILE__APPEND;
1943                 else if (mask & MAY_WRITE)
1944                         av |= FILE__WRITE;
1945
1946         } else {
1947                 if (mask & MAY_EXEC)
1948                         av |= DIR__SEARCH;
1949                 if (mask & MAY_WRITE)
1950                         av |= DIR__WRITE;
1951                 if (mask & MAY_READ)
1952                         av |= DIR__READ;
1953         }
1954
1955         return av;
1956 }
1957
1958 /* Convert a Linux file to an access vector. */
1959 static inline u32 file_to_av(struct file *file)
1960 {
1961         u32 av = 0;
1962
1963         if (file->f_mode & FMODE_READ)
1964                 av |= FILE__READ;
1965         if (file->f_mode & FMODE_WRITE) {
1966                 if (file->f_flags & O_APPEND)
1967                         av |= FILE__APPEND;
1968                 else
1969                         av |= FILE__WRITE;
1970         }
1971         if (!av) {
1972                 /*
1973                  * Special file opened with flags 3 for ioctl-only use.
1974                  */
1975                 av = FILE__IOCTL;
1976         }
1977
1978         return av;
1979 }
1980
1981 /*
1982  * Convert a file to an access vector and include the correct open
1983  * open permission.
1984  */
1985 static inline u32 open_file_to_av(struct file *file)
1986 {
1987         u32 av = file_to_av(file);
1988         struct inode *inode = file_inode(file);
1989
1990         if (selinux_policycap_openperm() &&
1991             inode->i_sb->s_magic != SOCKFS_MAGIC)
1992                 av |= FILE__OPEN;
1993
1994         return av;
1995 }
1996
1997 /* Hook functions begin here. */
1998
1999 static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2000 {
2001         u32 mysid = current_sid();
2002         u32 mgrsid = task_sid(mgr);
2003
2004         return avc_has_perm(&selinux_state,
2005                             mysid, mgrsid, SECCLASS_BINDER,
2006                             BINDER__SET_CONTEXT_MGR, NULL);
2007 }
2008
2009 static int selinux_binder_transaction(struct task_struct *from,
2010                                       struct task_struct *to)
2011 {
2012         u32 mysid = current_sid();
2013         u32 fromsid = task_sid(from);
2014         u32 tosid = task_sid(to);
2015         int rc;
2016
2017         if (mysid != fromsid) {
2018                 rc = avc_has_perm(&selinux_state,
2019                                   mysid, fromsid, SECCLASS_BINDER,
2020                                   BINDER__IMPERSONATE, NULL);
2021                 if (rc)
2022                         return rc;
2023         }
2024
2025         return avc_has_perm(&selinux_state,
2026                             fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2027                             NULL);
2028 }
2029
2030 static int selinux_binder_transfer_binder(struct task_struct *from,
2031                                           struct task_struct *to)
2032 {
2033         u32 fromsid = task_sid(from);
2034         u32 tosid = task_sid(to);
2035
2036         return avc_has_perm(&selinux_state,
2037                             fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2038                             NULL);
2039 }
2040
2041 static int selinux_binder_transfer_file(struct task_struct *from,
2042                                         struct task_struct *to,
2043                                         struct file *file)
2044 {
2045         u32 sid = task_sid(to);
2046         struct file_security_struct *fsec = selinux_file(file);
2047         struct dentry *dentry = file->f_path.dentry;
2048         struct inode_security_struct *isec;
2049         struct common_audit_data ad;
2050         int rc;
2051
2052         ad.type = LSM_AUDIT_DATA_PATH;
2053         ad.u.path = file->f_path;
2054
2055         if (sid != fsec->sid) {
2056                 rc = avc_has_perm(&selinux_state,
2057                                   sid, fsec->sid,
2058                                   SECCLASS_FD,
2059                                   FD__USE,
2060                                   &ad);
2061                 if (rc)
2062                         return rc;
2063         }
2064
2065 #ifdef CONFIG_BPF_SYSCALL
2066         rc = bpf_fd_pass(file, sid);
2067         if (rc)
2068                 return rc;
2069 #endif
2070
2071         if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2072                 return 0;
2073
2074         isec = backing_inode_security(dentry);
2075         return avc_has_perm(&selinux_state,
2076                             sid, isec->sid, isec->sclass, file_to_av(file),
2077                             &ad);
2078 }
2079
2080 static int selinux_ptrace_access_check(struct task_struct *child,
2081                                      unsigned int mode)
2082 {
2083         u32 sid = current_sid();
2084         u32 csid = task_sid(child);
2085
2086         if (mode & PTRACE_MODE_READ)
2087                 return avc_has_perm(&selinux_state,
2088                                     sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2089
2090         return avc_has_perm(&selinux_state,
2091                             sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2092 }
2093
2094 static int selinux_ptrace_traceme(struct task_struct *parent)
2095 {
2096         return avc_has_perm(&selinux_state,
2097                             task_sid(parent), current_sid(), SECCLASS_PROCESS,
2098                             PROCESS__PTRACE, NULL);
2099 }
2100
2101 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2102                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2103 {
2104         return avc_has_perm(&selinux_state,
2105                             current_sid(), task_sid(target), SECCLASS_PROCESS,
2106                             PROCESS__GETCAP, NULL);
2107 }
2108
2109 static int selinux_capset(struct cred *new, const struct cred *old,
2110                           const kernel_cap_t *effective,
2111                           const kernel_cap_t *inheritable,
2112                           const kernel_cap_t *permitted)
2113 {
2114         return avc_has_perm(&selinux_state,
2115                             cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2116                             PROCESS__SETCAP, NULL);
2117 }
2118
2119 /*
2120  * (This comment used to live with the selinux_task_setuid hook,
2121  * which was removed).
2122  *
2123  * Since setuid only affects the current process, and since the SELinux
2124  * controls are not based on the Linux identity attributes, SELinux does not
2125  * need to control this operation.  However, SELinux does control the use of
2126  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2127  */
2128
2129 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2130                            int cap, unsigned int opts)
2131 {
2132         return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2133 }
2134
2135 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2136 {
2137         const struct cred *cred = current_cred();
2138         int rc = 0;
2139
2140         if (!sb)
2141                 return 0;
2142
2143         switch (cmds) {
2144         case Q_SYNC:
2145         case Q_QUOTAON:
2146         case Q_QUOTAOFF:
2147         case Q_SETINFO:
2148         case Q_SETQUOTA:
2149         case Q_XQUOTAOFF:
2150         case Q_XQUOTAON:
2151         case Q_XSETQLIM:
2152                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2153                 break;
2154         case Q_GETFMT:
2155         case Q_GETINFO:
2156         case Q_GETQUOTA:
2157         case Q_XGETQUOTA:
2158         case Q_XGETQSTAT:
2159         case Q_XGETQSTATV:
2160         case Q_XGETNEXTQUOTA:
2161                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2162                 break;
2163         default:
2164                 rc = 0;  /* let the kernel handle invalid cmds */
2165                 break;
2166         }
2167         return rc;
2168 }
2169
2170 static int selinux_quota_on(struct dentry *dentry)
2171 {
2172         const struct cred *cred = current_cred();
2173
2174         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2175 }
2176
2177 static int selinux_syslog(int type)
2178 {
2179         switch (type) {
2180         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2181         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2182                 return avc_has_perm(&selinux_state,
2183                                     current_sid(), SECINITSID_KERNEL,
2184                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2185         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2186         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2187         /* Set level of messages printed to console */
2188         case SYSLOG_ACTION_CONSOLE_LEVEL:
2189                 return avc_has_perm(&selinux_state,
2190                                     current_sid(), SECINITSID_KERNEL,
2191                                     SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2192                                     NULL);
2193         }
2194         /* All other syslog types */
2195         return avc_has_perm(&selinux_state,
2196                             current_sid(), SECINITSID_KERNEL,
2197                             SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2198 }
2199
2200 /*
2201  * Check that a process has enough memory to allocate a new virtual
2202  * mapping. 0 means there is enough memory for the allocation to
2203  * succeed and -ENOMEM implies there is not.
2204  *
2205  * Do not audit the selinux permission check, as this is applied to all
2206  * processes that allocate mappings.
2207  */
2208 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2209 {
2210         int rc, cap_sys_admin = 0;
2211
2212         rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2213                                  CAP_OPT_NOAUDIT, true);
2214         if (rc == 0)
2215                 cap_sys_admin = 1;
2216
2217         return cap_sys_admin;
2218 }
2219
2220 /* binprm security operations */
2221
2222 static u32 ptrace_parent_sid(void)
2223 {
2224         u32 sid = 0;
2225         struct task_struct *tracer;
2226
2227         rcu_read_lock();
2228         tracer = ptrace_parent(current);
2229         if (tracer)
2230                 sid = task_sid(tracer);
2231         rcu_read_unlock();
2232
2233         return sid;
2234 }
2235
2236 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2237                             const struct task_security_struct *old_tsec,
2238                             const struct task_security_struct *new_tsec)
2239 {
2240         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2241         int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2242         int rc;
2243         u32 av;
2244
2245         if (!nnp && !nosuid)
2246                 return 0; /* neither NNP nor nosuid */
2247
2248         if (new_tsec->sid == old_tsec->sid)
2249                 return 0; /* No change in credentials */
2250
2251         /*
2252          * If the policy enables the nnp_nosuid_transition policy capability,
2253          * then we permit transitions under NNP or nosuid if the
2254          * policy allows the corresponding permission between
2255          * the old and new contexts.
2256          */
2257         if (selinux_policycap_nnp_nosuid_transition()) {
2258                 av = 0;
2259                 if (nnp)
2260                         av |= PROCESS2__NNP_TRANSITION;
2261                 if (nosuid)
2262                         av |= PROCESS2__NOSUID_TRANSITION;
2263                 rc = avc_has_perm(&selinux_state,
2264                                   old_tsec->sid, new_tsec->sid,
2265                                   SECCLASS_PROCESS2, av, NULL);
2266                 if (!rc)
2267                         return 0;
2268         }
2269
2270         /*
2271          * We also permit NNP or nosuid transitions to bounded SIDs,
2272          * i.e. SIDs that are guaranteed to only be allowed a subset
2273          * of the permissions of the current SID.
2274          */
2275         rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2276                                          new_tsec->sid);
2277         if (!rc)
2278                 return 0;
2279
2280         /*
2281          * On failure, preserve the errno values for NNP vs nosuid.
2282          * NNP:  Operation not permitted for caller.
2283          * nosuid:  Permission denied to file.
2284          */
2285         if (nnp)
2286                 return -EPERM;
2287         return -EACCES;
2288 }
2289
2290 static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2291 {
2292         const struct task_security_struct *old_tsec;
2293         struct task_security_struct *new_tsec;
2294         struct inode_security_struct *isec;
2295         struct common_audit_data ad;
2296         struct inode *inode = file_inode(bprm->file);
2297         int rc;
2298
2299         /* SELinux context only depends on initial program or script and not
2300          * the script interpreter */
2301
2302         old_tsec = selinux_cred(current_cred());
2303         new_tsec = selinux_cred(bprm->cred);
2304         isec = inode_security(inode);
2305
2306         /* Default to the current task SID. */
2307         new_tsec->sid = old_tsec->sid;
2308         new_tsec->osid = old_tsec->sid;
2309
2310         /* Reset fs, key, and sock SIDs on execve. */
2311         new_tsec->create_sid = 0;
2312         new_tsec->keycreate_sid = 0;
2313         new_tsec->sockcreate_sid = 0;
2314
2315         if (old_tsec->exec_sid) {
2316                 new_tsec->sid = old_tsec->exec_sid;
2317                 /* Reset exec SID on execve. */
2318                 new_tsec->exec_sid = 0;
2319
2320                 /* Fail on NNP or nosuid if not an allowed transition. */
2321                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2322                 if (rc)
2323                         return rc;
2324         } else {
2325                 /* Check for a default transition on this program. */
2326                 rc = security_transition_sid(&selinux_state, old_tsec->sid,
2327                                              isec->sid, SECCLASS_PROCESS, NULL,
2328                                              &new_tsec->sid);
2329                 if (rc)
2330                         return rc;
2331
2332                 /*
2333                  * Fallback to old SID on NNP or nosuid if not an allowed
2334                  * transition.
2335                  */
2336                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2337                 if (rc)
2338                         new_tsec->sid = old_tsec->sid;
2339         }
2340
2341         ad.type = LSM_AUDIT_DATA_FILE;
2342         ad.u.file = bprm->file;
2343
2344         if (new_tsec->sid == old_tsec->sid) {
2345                 rc = avc_has_perm(&selinux_state,
2346                                   old_tsec->sid, isec->sid,
2347                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2348                 if (rc)
2349                         return rc;
2350         } else {
2351                 /* Check permissions for the transition. */
2352                 rc = avc_has_perm(&selinux_state,
2353                                   old_tsec->sid, new_tsec->sid,
2354                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2355                 if (rc)
2356                         return rc;
2357
2358                 rc = avc_has_perm(&selinux_state,
2359                                   new_tsec->sid, isec->sid,
2360                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2361                 if (rc)
2362                         return rc;
2363
2364                 /* Check for shared state */
2365                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2366                         rc = avc_has_perm(&selinux_state,
2367                                           old_tsec->sid, new_tsec->sid,
2368                                           SECCLASS_PROCESS, PROCESS__SHARE,
2369                                           NULL);
2370                         if (rc)
2371                                 return -EPERM;
2372                 }
2373
2374                 /* Make sure that anyone attempting to ptrace over a task that
2375                  * changes its SID has the appropriate permit */
2376                 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2377                         u32 ptsid = ptrace_parent_sid();
2378                         if (ptsid != 0) {
2379                                 rc = avc_has_perm(&selinux_state,
2380                                                   ptsid, new_tsec->sid,
2381                                                   SECCLASS_PROCESS,
2382                                                   PROCESS__PTRACE, NULL);
2383                                 if (rc)
2384                                         return -EPERM;
2385                         }
2386                 }
2387
2388                 /* Clear any possibly unsafe personality bits on exec: */
2389                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2390
2391                 /* Enable secure mode for SIDs transitions unless
2392                    the noatsecure permission is granted between
2393                    the two SIDs, i.e. ahp returns 0. */
2394                 rc = avc_has_perm(&selinux_state,
2395                                   old_tsec->sid, new_tsec->sid,
2396                                   SECCLASS_PROCESS, PROCESS__NOATSECURE,
2397                                   NULL);
2398                 bprm->secureexec |= !!rc;
2399         }
2400
2401         return 0;
2402 }
2403
2404 static int match_file(const void *p, struct file *file, unsigned fd)
2405 {
2406         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2407 }
2408
2409 /* Derived from fs/exec.c:flush_old_files. */
2410 static inline void flush_unauthorized_files(const struct cred *cred,
2411                                             struct files_struct *files)
2412 {
2413         struct file *file, *devnull = NULL;
2414         struct tty_struct *tty;
2415         int drop_tty = 0;
2416         unsigned n;
2417
2418         tty = get_current_tty();
2419         if (tty) {
2420                 spin_lock(&tty->files_lock);
2421                 if (!list_empty(&tty->tty_files)) {
2422                         struct tty_file_private *file_priv;
2423
2424                         /* Revalidate access to controlling tty.
2425                            Use file_path_has_perm on the tty path directly
2426                            rather than using file_has_perm, as this particular
2427                            open file may belong to another process and we are
2428                            only interested in the inode-based check here. */
2429                         file_priv = list_first_entry(&tty->tty_files,
2430                                                 struct tty_file_private, list);
2431                         file = file_priv->file;
2432                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2433                                 drop_tty = 1;
2434                 }
2435                 spin_unlock(&tty->files_lock);
2436                 tty_kref_put(tty);
2437         }
2438         /* Reset controlling tty. */
2439         if (drop_tty)
2440                 no_tty();
2441
2442         /* Revalidate access to inherited open files. */
2443         n = iterate_fd(files, 0, match_file, cred);
2444         if (!n) /* none found? */
2445                 return;
2446
2447         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2448         if (IS_ERR(devnull))
2449                 devnull = NULL;
2450         /* replace all the matching ones with this */
2451         do {
2452                 replace_fd(n - 1, devnull, 0);
2453         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2454         if (devnull)
2455                 fput(devnull);
2456 }
2457
2458 /*
2459  * Prepare a process for imminent new credential changes due to exec
2460  */
2461 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2462 {
2463         struct task_security_struct *new_tsec;
2464         struct rlimit *rlim, *initrlim;
2465         int rc, i;
2466
2467         new_tsec = selinux_cred(bprm->cred);
2468         if (new_tsec->sid == new_tsec->osid)
2469                 return;
2470
2471         /* Close files for which the new task SID is not authorized. */
2472         flush_unauthorized_files(bprm->cred, current->files);
2473
2474         /* Always clear parent death signal on SID transitions. */
2475         current->pdeath_signal = 0;
2476
2477         /* Check whether the new SID can inherit resource limits from the old
2478          * SID.  If not, reset all soft limits to the lower of the current
2479          * task's hard limit and the init task's soft limit.
2480          *
2481          * Note that the setting of hard limits (even to lower them) can be
2482          * controlled by the setrlimit check.  The inclusion of the init task's
2483          * soft limit into the computation is to avoid resetting soft limits
2484          * higher than the default soft limit for cases where the default is
2485          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2486          */
2487         rc = avc_has_perm(&selinux_state,
2488                           new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2489                           PROCESS__RLIMITINH, NULL);
2490         if (rc) {
2491                 /* protect against do_prlimit() */
2492                 task_lock(current);
2493                 for (i = 0; i < RLIM_NLIMITS; i++) {
2494                         rlim = current->signal->rlim + i;
2495                         initrlim = init_task.signal->rlim + i;
2496                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2497                 }
2498                 task_unlock(current);
2499                 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2500                         update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2501         }
2502 }
2503
2504 /*
2505  * Clean up the process immediately after the installation of new credentials
2506  * due to exec
2507  */
2508 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2509 {
2510         const struct task_security_struct *tsec = selinux_cred(current_cred());
2511         u32 osid, sid;
2512         int rc;
2513
2514         osid = tsec->osid;
2515         sid = tsec->sid;
2516
2517         if (sid == osid)
2518                 return;
2519
2520         /* Check whether the new SID can inherit signal state from the old SID.
2521          * If not, clear itimers to avoid subsequent signal generation and
2522          * flush and unblock signals.
2523          *
2524          * This must occur _after_ the task SID has been updated so that any
2525          * kill done after the flush will be checked against the new SID.
2526          */
2527         rc = avc_has_perm(&selinux_state,
2528                           osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2529         if (rc) {
2530                 clear_itimer();
2531
2532                 spin_lock_irq(&current->sighand->siglock);
2533                 if (!fatal_signal_pending(current)) {
2534                         flush_sigqueue(&current->pending);
2535                         flush_sigqueue(&current->signal->shared_pending);
2536                         flush_signal_handlers(current, 1);
2537                         sigemptyset(&current->blocked);
2538                         recalc_sigpending();
2539                 }
2540                 spin_unlock_irq(&current->sighand->siglock);
2541         }
2542
2543         /* Wake up the parent if it is waiting so that it can recheck
2544          * wait permission to the new task SID. */
2545         read_lock(&tasklist_lock);
2546         __wake_up_parent(current, current->real_parent);
2547         read_unlock(&tasklist_lock);
2548 }
2549
2550 /* superblock security operations */
2551
2552 static int selinux_sb_alloc_security(struct super_block *sb)
2553 {
2554         struct superblock_security_struct *sbsec;
2555
2556         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
2557         if (!sbsec)
2558                 return -ENOMEM;
2559
2560         mutex_init(&sbsec->lock);
2561         INIT_LIST_HEAD(&sbsec->isec_head);
2562         spin_lock_init(&sbsec->isec_lock);
2563         sbsec->sb = sb;
2564         sbsec->sid = SECINITSID_UNLABELED;
2565         sbsec->def_sid = SECINITSID_FILE;
2566         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2567         sb->s_security = sbsec;
2568
2569         return 0;
2570 }
2571
2572 static void selinux_sb_free_security(struct super_block *sb)
2573 {
2574         superblock_free_security(sb);
2575 }
2576
2577 static inline int opt_len(const char *s)
2578 {
2579         bool open_quote = false;
2580         int len;
2581         char c;
2582
2583         for (len = 0; (c = s[len]) != '\0'; len++) {
2584                 if (c == '"')
2585                         open_quote = !open_quote;
2586                 if (c == ',' && !open_quote)
2587                         break;
2588         }
2589         return len;
2590 }
2591
2592 static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2593 {
2594         char *from = options;
2595         char *to = options;
2596         bool first = true;
2597         int rc;
2598
2599         while (1) {
2600                 int len = opt_len(from);
2601                 int token;
2602                 char *arg = NULL;
2603
2604                 token = match_opt_prefix(from, len, &arg);
2605
2606                 if (token != Opt_error) {
2607                         char *p, *q;
2608
2609                         /* strip quotes */
2610                         if (arg) {
2611                                 for (p = q = arg; p < from + len; p++) {
2612                                         char c = *p;
2613                                         if (c != '"')
2614                                                 *q++ = c;
2615                                 }
2616                                 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2617                                 if (!arg) {
2618                                         rc = -ENOMEM;
2619                                         goto free_opt;
2620                                 }
2621                         }
2622                         rc = selinux_add_opt(token, arg, mnt_opts);
2623                         if (unlikely(rc)) {
2624                                 kfree(arg);
2625                                 goto free_opt;
2626                         }
2627                 } else {
2628                         if (!first) {   // copy with preceding comma
2629                                 from--;
2630                                 len++;
2631                         }
2632                         if (to != from)
2633                                 memmove(to, from, len);
2634                         to += len;
2635                         first = false;
2636                 }
2637                 if (!from[len])
2638                         break;
2639                 from += len + 1;
2640         }
2641         *to = '\0';
2642         return 0;
2643
2644 free_opt:
2645         if (*mnt_opts) {
2646                 selinux_free_mnt_opts(*mnt_opts);
2647                 *mnt_opts = NULL;
2648         }
2649         return rc;
2650 }
2651
2652 static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2653 {
2654         struct selinux_mnt_opts *opts = mnt_opts;
2655         struct superblock_security_struct *sbsec = sb->s_security;
2656         u32 sid;
2657         int rc;
2658
2659         if (!(sbsec->flags & SE_SBINITIALIZED))
2660                 return 0;
2661
2662         if (!opts)
2663                 return 0;
2664
2665         if (opts->fscontext) {
2666                 rc = parse_sid(sb, opts->fscontext, &sid);
2667                 if (rc)
2668                         return rc;
2669                 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2670                         goto out_bad_option;
2671         }
2672         if (opts->context) {
2673                 rc = parse_sid(sb, opts->context, &sid);
2674                 if (rc)
2675                         return rc;
2676                 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2677                         goto out_bad_option;
2678         }
2679         if (opts->rootcontext) {
2680                 struct inode_security_struct *root_isec;
2681                 root_isec = backing_inode_security(sb->s_root);
2682                 rc = parse_sid(sb, opts->rootcontext, &sid);
2683                 if (rc)
2684                         return rc;
2685                 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2686                         goto out_bad_option;
2687         }
2688         if (opts->defcontext) {
2689                 rc = parse_sid(sb, opts->defcontext, &sid);
2690                 if (rc)
2691                         return rc;
2692                 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2693                         goto out_bad_option;
2694         }
2695         return 0;
2696
2697 out_bad_option:
2698         pr_warn("SELinux: unable to change security options "
2699                "during remount (dev %s, type=%s)\n", sb->s_id,
2700                sb->s_type->name);
2701         return -EINVAL;
2702 }
2703
2704 static int selinux_sb_kern_mount(struct super_block *sb)
2705 {
2706         const struct cred *cred = current_cred();
2707         struct common_audit_data ad;
2708
2709         ad.type = LSM_AUDIT_DATA_DENTRY;
2710         ad.u.dentry = sb->s_root;
2711         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2712 }
2713
2714 static int selinux_sb_statfs(struct dentry *dentry)
2715 {
2716         const struct cred *cred = current_cred();
2717         struct common_audit_data ad;
2718
2719         ad.type = LSM_AUDIT_DATA_DENTRY;
2720         ad.u.dentry = dentry->d_sb->s_root;
2721         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2722 }
2723
2724 static int selinux_mount(const char *dev_name,
2725                          const struct path *path,
2726                          const char *type,
2727                          unsigned long flags,
2728                          void *data)
2729 {
2730         const struct cred *cred = current_cred();
2731
2732         if (flags & MS_REMOUNT)
2733                 return superblock_has_perm(cred, path->dentry->d_sb,
2734                                            FILESYSTEM__REMOUNT, NULL);
2735         else
2736                 return path_has_perm(cred, path, FILE__MOUNTON);
2737 }
2738
2739 static int selinux_move_mount(const struct path *from_path,
2740                               const struct path *to_path)
2741 {
2742         const struct cred *cred = current_cred();
2743
2744         return path_has_perm(cred, to_path, FILE__MOUNTON);
2745 }
2746
2747 static int selinux_umount(struct vfsmount *mnt, int flags)
2748 {
2749         const struct cred *cred = current_cred();
2750
2751         return superblock_has_perm(cred, mnt->mnt_sb,
2752                                    FILESYSTEM__UNMOUNT, NULL);
2753 }
2754
2755 static int selinux_fs_context_dup(struct fs_context *fc,
2756                                   struct fs_context *src_fc)
2757 {
2758         const struct selinux_mnt_opts *src = src_fc->security;
2759         struct selinux_mnt_opts *opts;
2760
2761         if (!src)
2762                 return 0;
2763
2764         fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
2765         if (!fc->security)
2766                 return -ENOMEM;
2767
2768         opts = fc->security;
2769
2770         if (src->fscontext) {
2771                 opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL);
2772                 if (!opts->fscontext)
2773                         return -ENOMEM;
2774         }
2775         if (src->context) {
2776                 opts->context = kstrdup(src->context, GFP_KERNEL);
2777                 if (!opts->context)
2778                         return -ENOMEM;
2779         }
2780         if (src->rootcontext) {
2781                 opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL);
2782                 if (!opts->rootcontext)
2783                         return -ENOMEM;
2784         }
2785         if (src->defcontext) {
2786                 opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL);
2787                 if (!opts->defcontext)
2788                         return -ENOMEM;
2789         }
2790         return 0;
2791 }
2792
2793 static const struct fs_parameter_spec selinux_fs_parameters[] = {
2794         fsparam_string(CONTEXT_STR,     Opt_context),
2795         fsparam_string(DEFCONTEXT_STR,  Opt_defcontext),
2796         fsparam_string(FSCONTEXT_STR,   Opt_fscontext),
2797         fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2798         fsparam_flag  (SECLABEL_STR,    Opt_seclabel),
2799         {}
2800 };
2801
2802 static int selinux_fs_context_parse_param(struct fs_context *fc,
2803                                           struct fs_parameter *param)
2804 {
2805         struct fs_parse_result result;
2806         int opt, rc;
2807
2808         opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2809         if (opt < 0)
2810                 return opt;
2811
2812         rc = selinux_add_opt(opt, param->string, &fc->security);
2813         if (!rc) {
2814                 param->string = NULL;
2815                 rc = 1;
2816         }
2817         return rc;
2818 }
2819
2820 /* inode security operations */
2821
2822 static int selinux_inode_alloc_security(struct inode *inode)
2823 {
2824         struct inode_security_struct *isec = selinux_inode(inode);
2825         u32 sid = current_sid();
2826
2827         spin_lock_init(&isec->lock);
2828         INIT_LIST_HEAD(&isec->list);
2829         isec->inode = inode;
2830         isec->sid = SECINITSID_UNLABELED;
2831         isec->sclass = SECCLASS_FILE;
2832         isec->task_sid = sid;
2833         isec->initialized = LABEL_INVALID;
2834
2835         return 0;
2836 }
2837
2838 static void selinux_inode_free_security(struct inode *inode)
2839 {
2840         inode_free_security(inode);
2841 }
2842
2843 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2844                                         const struct qstr *name, void **ctx,
2845                                         u32 *ctxlen)
2846 {
2847         u32 newsid;
2848         int rc;
2849
2850         rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2851                                            d_inode(dentry->d_parent), name,
2852                                            inode_mode_to_security_class(mode),
2853                                            &newsid);
2854         if (rc)
2855                 return rc;
2856
2857         return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
2858                                        ctxlen);
2859 }
2860
2861 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2862                                           struct qstr *name,
2863                                           const struct cred *old,
2864                                           struct cred *new)
2865 {
2866         u32 newsid;
2867         int rc;
2868         struct task_security_struct *tsec;
2869
2870         rc = selinux_determine_inode_label(selinux_cred(old),
2871                                            d_inode(dentry->d_parent), name,
2872                                            inode_mode_to_security_class(mode),
2873                                            &newsid);
2874         if (rc)
2875                 return rc;
2876
2877         tsec = selinux_cred(new);
2878         tsec->create_sid = newsid;
2879         return 0;
2880 }
2881
2882 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2883                                        const struct qstr *qstr,
2884                                        const char **name,
2885                                        void **value, size_t *len)
2886 {
2887         const struct task_security_struct *tsec = selinux_cred(current_cred());
2888         struct superblock_security_struct *sbsec;
2889         u32 newsid, clen;
2890         int rc;
2891         char *context;
2892
2893         sbsec = dir->i_sb->s_security;
2894
2895         newsid = tsec->create_sid;
2896
2897         rc = selinux_determine_inode_label(tsec, dir, qstr,
2898                 inode_mode_to_security_class(inode->i_mode),
2899                 &newsid);
2900         if (rc)
2901                 return rc;
2902
2903         /* Possibly defer initialization to selinux_complete_init. */
2904         if (sbsec->flags & SE_SBINITIALIZED) {
2905                 struct inode_security_struct *isec = selinux_inode(inode);
2906                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2907                 isec->sid = newsid;
2908                 isec->initialized = LABEL_INITIALIZED;
2909         }
2910
2911         if (!selinux_initialized(&selinux_state) ||
2912             !(sbsec->flags & SBLABEL_MNT))
2913                 return -EOPNOTSUPP;
2914
2915         if (name)
2916                 *name = XATTR_SELINUX_SUFFIX;
2917
2918         if (value && len) {
2919                 rc = security_sid_to_context_force(&selinux_state, newsid,
2920                                                    &context, &clen);
2921                 if (rc)
2922                         return rc;
2923                 *value = context;
2924                 *len = clen;
2925         }
2926
2927         return 0;
2928 }
2929
2930 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2931 {
2932         return may_create(dir, dentry, SECCLASS_FILE);
2933 }
2934
2935 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2936 {
2937         return may_link(dir, old_dentry, MAY_LINK);
2938 }
2939
2940 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2941 {
2942         return may_link(dir, dentry, MAY_UNLINK);
2943 }
2944
2945 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2946 {
2947         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2948 }
2949
2950 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2951 {
2952         return may_create(dir, dentry, SECCLASS_DIR);
2953 }
2954
2955 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2956 {
2957         return may_link(dir, dentry, MAY_RMDIR);
2958 }
2959
2960 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2961 {
2962         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2963 }
2964
2965 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2966                                 struct inode *new_inode, struct dentry *new_dentry)
2967 {
2968         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2969 }
2970
2971 static int selinux_inode_readlink(struct dentry *dentry)
2972 {
2973         const struct cred *cred = current_cred();
2974
2975         return dentry_has_perm(cred, dentry, FILE__READ);
2976 }
2977
2978 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2979                                      bool rcu)
2980 {
2981         const struct cred *cred = current_cred();
2982         struct common_audit_data ad;
2983         struct inode_security_struct *isec;
2984         u32 sid;
2985
2986         validate_creds(cred);
2987
2988         ad.type = LSM_AUDIT_DATA_DENTRY;
2989         ad.u.dentry = dentry;
2990         sid = cred_sid(cred);
2991         isec = inode_security_rcu(inode, rcu);
2992         if (IS_ERR(isec))
2993                 return PTR_ERR(isec);
2994
2995         return avc_has_perm_flags(&selinux_state,
2996                                   sid, isec->sid, isec->sclass, FILE__READ, &ad,
2997                                   rcu ? MAY_NOT_BLOCK : 0);
2998 }
2999
3000 static noinline int audit_inode_permission(struct inode *inode,
3001                                            u32 perms, u32 audited, u32 denied,
3002                                            int result)
3003 {
3004         struct common_audit_data ad;
3005         struct inode_security_struct *isec = selinux_inode(inode);
3006         int rc;
3007
3008         ad.type = LSM_AUDIT_DATA_INODE;
3009         ad.u.inode = inode;
3010
3011         rc = slow_avc_audit(&selinux_state,
3012                             current_sid(), isec->sid, isec->sclass, perms,
3013                             audited, denied, result, &ad);
3014         if (rc)
3015                 return rc;
3016         return 0;
3017 }
3018
3019 static int selinux_inode_permission(struct inode *inode, int mask)
3020 {
3021         const struct cred *cred = current_cred();
3022         u32 perms;
3023         bool from_access;
3024         bool no_block = mask & MAY_NOT_BLOCK;
3025         struct inode_security_struct *isec;
3026         u32 sid;
3027         struct av_decision avd;
3028         int rc, rc2;
3029         u32 audited, denied;
3030
3031         from_access = mask & MAY_ACCESS;
3032         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3033
3034         /* No permission to check.  Existence test. */
3035         if (!mask)
3036                 return 0;
3037
3038         validate_creds(cred);
3039
3040         if (unlikely(IS_PRIVATE(inode)))
3041                 return 0;
3042
3043         perms = file_mask_to_av(inode->i_mode, mask);
3044
3045         sid = cred_sid(cred);
3046         isec = inode_security_rcu(inode, no_block);
3047         if (IS_ERR(isec))
3048                 return PTR_ERR(isec);
3049
3050         rc = avc_has_perm_noaudit(&selinux_state,
3051                                   sid, isec->sid, isec->sclass, perms,
3052                                   no_block ? AVC_NONBLOCKING : 0,
3053                                   &avd);
3054         audited = avc_audit_required(perms, &avd, rc,
3055                                      from_access ? FILE__AUDIT_ACCESS : 0,
3056                                      &denied);
3057         if (likely(!audited))
3058                 return rc;
3059
3060         /* fall back to ref-walk if we have to generate audit */
3061         if (no_block)
3062                 return -ECHILD;
3063
3064         rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3065         if (rc2)
3066                 return rc2;
3067         return rc;
3068 }
3069
3070 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3071 {
3072         const struct cred *cred = current_cred();
3073         struct inode *inode = d_backing_inode(dentry);
3074         unsigned int ia_valid = iattr->ia_valid;
3075         __u32 av = FILE__WRITE;
3076
3077         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3078         if (ia_valid & ATTR_FORCE) {
3079                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3080                               ATTR_FORCE);
3081                 if (!ia_valid)
3082                         return 0;
3083         }
3084
3085         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3086                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3087                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3088
3089         if (selinux_policycap_openperm() &&
3090             inode->i_sb->s_magic != SOCKFS_MAGIC &&
3091             (ia_valid & ATTR_SIZE) &&
3092             !(ia_valid & ATTR_FILE))
3093                 av |= FILE__OPEN;
3094
3095         return dentry_has_perm(cred, dentry, av);
3096 }
3097
3098 static int selinux_inode_getattr(const struct path *path)
3099 {
3100         return path_has_perm(current_cred(), path, FILE__GETATTR);
3101 }
3102
3103 static bool has_cap_mac_admin(bool audit)
3104 {
3105         const struct cred *cred = current_cred();
3106         unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3107
3108         if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3109                 return false;
3110         if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3111                 return false;
3112         return true;
3113 }
3114
3115 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3116                                   const void *value, size_t size, int flags)
3117 {
3118         struct inode *inode = d_backing_inode(dentry);
3119         struct inode_security_struct *isec;
3120         struct superblock_security_struct *sbsec;
3121         struct common_audit_data ad;
3122         u32 newsid, sid = current_sid();
3123         int rc = 0;
3124
3125         if (strcmp(name, XATTR_NAME_SELINUX)) {
3126                 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3127                 if (rc)
3128                         return rc;
3129
3130                 /* Not an attribute we recognize, so just check the
3131                    ordinary setattr permission. */
3132                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3133         }
3134
3135         if (!selinux_initialized(&selinux_state))
3136                 return (inode_owner_or_capable(inode) ? 0 : -EPERM);
3137
3138         sbsec = inode->i_sb->s_security;
3139         if (!(sbsec->flags & SBLABEL_MNT))
3140                 return -EOPNOTSUPP;
3141
3142         if (!inode_owner_or_capable(inode))
3143                 return -EPERM;
3144
3145         ad.type = LSM_AUDIT_DATA_DENTRY;
3146         ad.u.dentry = dentry;
3147
3148         isec = backing_inode_security(dentry);
3149         rc = avc_has_perm(&selinux_state,
3150                           sid, isec->sid, isec->sclass,
3151                           FILE__RELABELFROM, &ad);
3152         if (rc)
3153                 return rc;
3154
3155         rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3156                                      GFP_KERNEL);
3157         if (rc == -EINVAL) {
3158                 if (!has_cap_mac_admin(true)) {
3159                         struct audit_buffer *ab;
3160                         size_t audit_size;
3161
3162                         /* We strip a nul only if it is at the end, otherwise the
3163                          * context contains a nul and we should audit that */
3164                         if (value) {
3165                                 const char *str = value;
3166
3167                                 if (str[size - 1] == '\0')
3168                                         audit_size = size - 1;
3169                                 else
3170                                         audit_size = size;
3171                         } else {
3172                                 audit_size = 0;
3173                         }
3174                         ab = audit_log_start(audit_context(),
3175                                              GFP_ATOMIC, AUDIT_SELINUX_ERR);
3176                         audit_log_format(ab, "op=setxattr invalid_context=");
3177                         audit_log_n_untrustedstring(ab, value, audit_size);
3178                         audit_log_end(ab);
3179
3180                         return rc;
3181                 }
3182                 rc = security_context_to_sid_force(&selinux_state, value,
3183                                                    size, &newsid);
3184         }
3185         if (rc)
3186                 return rc;
3187
3188         rc = avc_has_perm(&selinux_state,
3189                           sid, newsid, isec->sclass,
3190                           FILE__RELABELTO, &ad);
3191         if (rc)
3192                 return rc;
3193
3194         rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3195                                           sid, isec->sclass);
3196         if (rc)
3197                 return rc;
3198
3199         return avc_has_perm(&selinux_state,
3200                             newsid,
3201                             sbsec->sid,
3202                             SECCLASS_FILESYSTEM,
3203                             FILESYSTEM__ASSOCIATE,
3204                             &ad);
3205 }
3206
3207 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3208                                         const void *value, size_t size,
3209                                         int flags)
3210 {
3211         struct inode *inode = d_backing_inode(dentry);
3212         struct inode_security_struct *isec;
3213         u32 newsid;
3214         int rc;
3215
3216         if (strcmp(name, XATTR_NAME_SELINUX)) {
3217                 /* Not an attribute we recognize, so nothing to do. */
3218                 return;
3219         }
3220
3221         if (!selinux_initialized(&selinux_state)) {
3222                 /* If we haven't even been initialized, then we can't validate
3223                  * against a policy, so leave the label as invalid. It may
3224                  * resolve to a valid label on the next revalidation try if
3225                  * we've since initialized.
3226                  */
3227                 return;
3228         }
3229
3230         rc = security_context_to_sid_force(&selinux_state, value, size,
3231                                            &newsid);
3232         if (rc) {
3233                 pr_err("SELinux:  unable to map context to SID"
3234                        "for (%s, %lu), rc=%d\n",
3235                        inode->i_sb->s_id, inode->i_ino, -rc);
3236                 return;
3237         }
3238
3239         isec = backing_inode_security(dentry);
3240         spin_lock(&isec->lock);
3241         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3242         isec->sid = newsid;
3243         isec->initialized = LABEL_INITIALIZED;
3244         spin_unlock(&isec->lock);
3245
3246         return;
3247 }
3248
3249 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3250 {
3251         const struct cred *cred = current_cred();
3252
3253         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3254 }
3255
3256 static int selinux_inode_listxattr(struct dentry *dentry)
3257 {
3258         const struct cred *cred = current_cred();
3259
3260         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3261 }
3262
3263 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3264 {
3265         if (strcmp(name, XATTR_NAME_SELINUX)) {
3266                 int rc = cap_inode_removexattr(dentry, name);
3267                 if (rc)
3268                         return rc;
3269
3270                 /* Not an attribute we recognize, so just check the
3271                    ordinary setattr permission. */
3272                 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3273         }
3274
3275         /* No one is allowed to remove a SELinux security label.
3276            You can change the label, but all data must be labeled. */
3277         return -EACCES;
3278 }
3279
3280 static int selinux_path_notify(const struct path *path, u64 mask,
3281                                                 unsigned int obj_type)
3282 {
3283         int ret;
3284         u32 perm;
3285
3286         struct common_audit_data ad;
3287
3288         ad.type = LSM_AUDIT_DATA_PATH;
3289         ad.u.path = *path;
3290
3291         /*
3292          * Set permission needed based on the type of mark being set.
3293          * Performs an additional check for sb watches.
3294          */
3295         switch (obj_type) {
3296         case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3297                 perm = FILE__WATCH_MOUNT;
3298                 break;
3299         case FSNOTIFY_OBJ_TYPE_SB:
3300                 perm = FILE__WATCH_SB;
3301                 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3302                                                 FILESYSTEM__WATCH, &ad);
3303                 if (ret)
3304                         return ret;
3305                 break;
3306         case FSNOTIFY_OBJ_TYPE_INODE:
3307                 perm = FILE__WATCH;
3308                 break;
3309         default:
3310                 return -EINVAL;
3311         }
3312
3313         /* blocking watches require the file:watch_with_perm permission */
3314         if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3315                 perm |= FILE__WATCH_WITH_PERM;
3316
3317         /* watches on read-like events need the file:watch_reads permission */
3318         if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3319                 perm |= FILE__WATCH_READS;
3320
3321         return path_has_perm(current_cred(), path, perm);
3322 }
3323
3324 /*
3325  * Copy the inode security context value to the user.
3326  *
3327  * Permission check is handled by selinux_inode_getxattr hook.
3328  */
3329 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3330 {
3331         u32 size;
3332         int error;
3333         char *context = NULL;
3334         struct inode_security_struct *isec;
3335
3336         /*
3337          * If we're not initialized yet, then we can't validate contexts, so
3338          * just let vfs_getxattr fall back to using the on-disk xattr.
3339          */
3340         if (!selinux_initialized(&selinux_state) ||
3341             strcmp(name, XATTR_SELINUX_SUFFIX))
3342                 return -EOPNOTSUPP;
3343
3344         /*
3345          * If the caller has CAP_MAC_ADMIN, then get the raw context
3346          * value even if it is not defined by current policy; otherwise,
3347          * use the in-core value under current policy.
3348          * Use the non-auditing forms of the permission checks since
3349          * getxattr may be called by unprivileged processes commonly
3350          * and lack of permission just means that we fall back to the
3351          * in-core context value, not a denial.
3352          */
3353         isec = inode_security(inode);
3354         if (has_cap_mac_admin(false))
3355                 error = security_sid_to_context_force(&selinux_state,
3356                                                       isec->sid, &context,
3357                                                       &size);
3358         else
3359                 error = security_sid_to_context(&selinux_state, isec->sid,
3360                                                 &context, &size);
3361         if (error)
3362                 return error;
3363         error = size;
3364         if (alloc) {
3365                 *buffer = context;
3366                 goto out_nofree;
3367         }
3368         kfree(context);
3369 out_nofree:
3370         return error;
3371 }
3372
3373 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3374                                      const void *value, size_t size, int flags)
3375 {
3376         struct inode_security_struct *isec = inode_security_novalidate(inode);
3377         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
3378         u32 newsid;
3379         int rc;
3380
3381         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3382                 return -EOPNOTSUPP;
3383
3384         if (!(sbsec->flags & SBLABEL_MNT))
3385                 return -EOPNOTSUPP;
3386
3387         if (!value || !size)
3388                 return -EACCES;
3389
3390         rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3391                                      GFP_KERNEL);
3392         if (rc)
3393                 return rc;
3394
3395         spin_lock(&isec->lock);
3396         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3397         isec->sid = newsid;
3398         isec->initialized = LABEL_INITIALIZED;
3399         spin_unlock(&isec->lock);
3400         return 0;
3401 }
3402
3403 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3404 {
3405         const int len = sizeof(XATTR_NAME_SELINUX);
3406         if (buffer && len <= buffer_size)
3407                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3408         return len;
3409 }
3410
3411 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3412 {
3413         struct inode_security_struct *isec = inode_security_novalidate(inode);
3414         *secid = isec->sid;
3415 }
3416
3417 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3418 {
3419         u32 sid;
3420         struct task_security_struct *tsec;
3421         struct cred *new_creds = *new;
3422
3423         if (new_creds == NULL) {
3424                 new_creds = prepare_creds();
3425                 if (!new_creds)
3426                         return -ENOMEM;
3427         }
3428
3429         tsec = selinux_cred(new_creds);
3430         /* Get label from overlay inode and set it in create_sid */
3431         selinux_inode_getsecid(d_inode(src), &sid);
3432         tsec->create_sid = sid;
3433         *new = new_creds;
3434         return 0;
3435 }
3436
3437 static int selinux_inode_copy_up_xattr(const char *name)
3438 {
3439         /* The copy_up hook above sets the initial context on an inode, but we
3440          * don't then want to overwrite it by blindly copying all the lower
3441          * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3442          */
3443         if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3444                 return 1; /* Discard */
3445         /*
3446          * Any other attribute apart from SELINUX is not claimed, supported
3447          * by selinux.
3448          */
3449         return -EOPNOTSUPP;
3450 }
3451
3452 /* kernfs node operations */
3453
3454 static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3455                                         struct kernfs_node *kn)
3456 {
3457         const struct task_security_struct *tsec = selinux_cred(current_cred());
3458         u32 parent_sid, newsid, clen;
3459         int rc;
3460         char *context;
3461
3462         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3463         if (rc == -ENODATA)
3464                 return 0;
3465         else if (rc < 0)
3466                 return rc;
3467
3468         clen = (u32)rc;
3469         context = kmalloc(clen, GFP_KERNEL);
3470         if (!context)
3471                 return -ENOMEM;
3472
3473         rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3474         if (rc < 0) {
3475                 kfree(context);
3476                 return rc;
3477         }
3478
3479         rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid,
3480                                      GFP_KERNEL);
3481         kfree(context);
3482         if (rc)
3483                 return rc;
3484
3485         if (tsec->create_sid) {
3486                 newsid = tsec->create_sid;
3487         } else {
3488                 u16 secclass = inode_mode_to_security_class(kn->mode);
3489                 struct qstr q;
3490
3491                 q.name = kn->name;
3492                 q.hash_len = hashlen_string(kn_dir, kn->name);
3493
3494                 rc = security_transition_sid(&selinux_state, tsec->sid,
3495                                              parent_sid, secclass, &q,
3496                                              &newsid);
3497                 if (rc)
3498                         return rc;
3499         }
3500
3501         rc = security_sid_to_context_force(&selinux_state, newsid,
3502                                            &context, &clen);
3503         if (rc)
3504                 return rc;
3505
3506         rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3507                               XATTR_CREATE);
3508         kfree(context);
3509         return rc;
3510 }
3511
3512
3513 /* file security operations */
3514
3515 static int selinux_revalidate_file_permission(struct file *file, int mask)
3516 {
3517         const struct cred *cred = current_cred();
3518         struct inode *inode = file_inode(file);
3519
3520         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3521         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3522                 mask |= MAY_APPEND;
3523
3524         return file_has_perm(cred, file,
3525                              file_mask_to_av(inode->i_mode, mask));
3526 }
3527
3528 static int selinux_file_permission(struct file *file, int mask)
3529 {
3530         struct inode *inode = file_inode(file);
3531         struct file_security_struct *fsec = selinux_file(file);
3532         struct inode_security_struct *isec;
3533         u32 sid = current_sid();
3534
3535         if (!mask)
3536                 /* No permission to check.  Existence test. */
3537                 return 0;
3538
3539         isec = inode_security(inode);
3540         if (sid == fsec->sid && fsec->isid == isec->sid &&
3541             fsec->pseqno == avc_policy_seqno(&selinux_state))
3542                 /* No change since file_open check. */
3543                 return 0;
3544
3545         return selinux_revalidate_file_permission(file, mask);
3546 }
3547
3548 static int selinux_file_alloc_security(struct file *file)
3549 {
3550         struct file_security_struct *fsec = selinux_file(file);
3551         u32 sid = current_sid();
3552
3553         fsec->sid = sid;
3554         fsec->fown_sid = sid;
3555
3556         return 0;
3557 }
3558
3559 /*
3560  * Check whether a task has the ioctl permission and cmd
3561  * operation to an inode.
3562  */
3563 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3564                 u32 requested, u16 cmd)
3565 {
3566         struct common_audit_data ad;
3567         struct file_security_struct *fsec = selinux_file(file);
3568         struct inode *inode = file_inode(file);
3569         struct inode_security_struct *isec;
3570         struct lsm_ioctlop_audit ioctl;
3571         u32 ssid = cred_sid(cred);
3572         int rc;
3573         u8 driver = cmd >> 8;
3574         u8 xperm = cmd & 0xff;
3575
3576         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3577         ad.u.op = &ioctl;
3578         ad.u.op->cmd = cmd;
3579         ad.u.op->path = file->f_path;
3580
3581         if (ssid != fsec->sid) {
3582                 rc = avc_has_perm(&selinux_state,
3583                                   ssid, fsec->sid,
3584                                 SECCLASS_FD,
3585                                 FD__USE,
3586                                 &ad);
3587                 if (rc)
3588                         goto out;
3589         }
3590
3591         if (unlikely(IS_PRIVATE(inode)))
3592                 return 0;
3593
3594         isec = inode_security(inode);
3595         rc = avc_has_extended_perms(&selinux_state,
3596                                     ssid, isec->sid, isec->sclass,
3597                                     requested, driver, xperm, &ad);
3598 out:
3599         return rc;
3600 }
3601
3602 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3603                               unsigned long arg)
3604 {
3605         const struct cred *cred = current_cred();
3606         int error = 0;
3607
3608         switch (cmd) {
3609         case FIONREAD:
3610         case FIBMAP:
3611         case FIGETBSZ:
3612         case FS_IOC_GETFLAGS:
3613         case FS_IOC_GETVERSION:
3614                 error = file_has_perm(cred, file, FILE__GETATTR);
3615                 break;
3616
3617         case FS_IOC_SETFLAGS:
3618         case FS_IOC_SETVERSION:
3619                 error = file_has_perm(cred, file, FILE__SETATTR);
3620                 break;
3621
3622         /* sys_ioctl() checks */
3623         case FIONBIO:
3624         case FIOASYNC:
3625                 error = file_has_perm(cred, file, 0);
3626                 break;
3627
3628         case KDSKBENT:
3629         case KDSKBSENT:
3630                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3631                                             CAP_OPT_NONE, true);
3632                 break;
3633
3634         /* default case assumes that the command will go
3635          * to the file's ioctl() function.
3636          */
3637         default:
3638                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3639         }
3640         return error;
3641 }
3642
3643 static int default_noexec __ro_after_init;
3644
3645 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3646 {
3647         const struct cred *cred = current_cred();
3648         u32 sid = cred_sid(cred);
3649         int rc = 0;
3650
3651         if (default_noexec &&
3652             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3653                                    (!shared && (prot & PROT_WRITE)))) {
3654                 /*
3655                  * We are making executable an anonymous mapping or a
3656                  * private file mapping that will also be writable.
3657                  * This has an additional check.
3658                  */
3659                 rc = avc_has_perm(&selinux_state,
3660                                   sid, sid, SECCLASS_PROCESS,
3661                                   PROCESS__EXECMEM, NULL);
3662                 if (rc)
3663                         goto error;
3664         }
3665
3666         if (file) {
3667                 /* read access is always possible with a mapping */
3668                 u32 av = FILE__READ;
3669
3670                 /* write access only matters if the mapping is shared */
3671                 if (shared && (prot & PROT_WRITE))
3672                         av |= FILE__WRITE;
3673
3674                 if (prot & PROT_EXEC)
3675                         av |= FILE__EXECUTE;
3676
3677                 return file_has_perm(cred, file, av);
3678         }
3679
3680 error:
3681         return rc;
3682 }
3683
3684 static int selinux_mmap_addr(unsigned long addr)
3685 {
3686         int rc = 0;
3687
3688         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3689                 u32 sid = current_sid();
3690                 rc = avc_has_perm(&selinux_state,
3691                                   sid, sid, SECCLASS_MEMPROTECT,
3692                                   MEMPROTECT__MMAP_ZERO, NULL);
3693         }
3694
3695         return rc;
3696 }
3697
3698 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3699                              unsigned long prot, unsigned long flags)
3700 {
3701         struct common_audit_data ad;
3702         int rc;
3703
3704         if (file) {
3705                 ad.type = LSM_AUDIT_DATA_FILE;
3706                 ad.u.file = file;
3707                 rc = inode_has_perm(current_cred(), file_inode(file),
3708                                     FILE__MAP, &ad);
3709                 if (rc)
3710                         return rc;
3711         }
3712
3713         if (selinux_state.checkreqprot)
3714                 prot = reqprot;
3715
3716         return file_map_prot_check(file, prot,
3717                                    (flags & MAP_TYPE) == MAP_SHARED);
3718 }
3719
3720 static int selinux_file_mprotect(struct vm_area_struct *vma,
3721                                  unsigned long reqprot,
3722                                  unsigned long prot)
3723 {
3724         const struct cred *cred = current_cred();
3725         u32 sid = cred_sid(cred);
3726
3727         if (selinux_state.checkreqprot)
3728                 prot = reqprot;
3729
3730         if (default_noexec &&
3731             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3732                 int rc = 0;
3733                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3734                     vma->vm_end <= vma->vm_mm->brk) {
3735                         rc = avc_has_perm(&selinux_state,
3736                                           sid, sid, SECCLASS_PROCESS,
3737                                           PROCESS__EXECHEAP, NULL);
3738                 } else if (!vma->vm_file &&
3739                            ((vma->vm_start <= vma->vm_mm->start_stack &&
3740                              vma->vm_end >= vma->vm_mm->start_stack) ||
3741                             vma_is_stack_for_current(vma))) {
3742                         rc = avc_has_perm(&selinux_state,
3743                                           sid, sid, SECCLASS_PROCESS,
3744                                           PROCESS__EXECSTACK, NULL);
3745                 } else if (vma->vm_file && vma->anon_vma) {
3746                         /*
3747                          * We are making executable a file mapping that has
3748                          * had some COW done. Since pages might have been
3749                          * written, check ability to execute the possibly
3750                          * modified content.  This typically should only
3751                          * occur for text relocations.
3752                          */
3753                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3754                 }
3755                 if (rc)
3756                         return rc;
3757         }
3758
3759         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3760 }
3761
3762 static int selinux_file_lock(struct file *file, unsigned int cmd)
3763 {
3764         const struct cred *cred = current_cred();
3765
3766         return file_has_perm(cred, file, FILE__LOCK);
3767 }
3768
3769 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3770                               unsigned long arg)
3771 {
3772         const struct cred *cred = current_cred();
3773         int err = 0;
3774
3775         switch (cmd) {
3776         case F_SETFL:
3777                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3778                         err = file_has_perm(cred, file, FILE__WRITE);
3779                         break;
3780                 }
3781                 fallthrough;
3782         case F_SETOWN:
3783         case F_SETSIG:
3784         case F_GETFL:
3785         case F_GETOWN:
3786         case F_GETSIG:
3787         case F_GETOWNER_UIDS:
3788                 /* Just check FD__USE permission */
3789                 err = file_has_perm(cred, file, 0);
3790                 break;
3791         case F_GETLK:
3792         case F_SETLK:
3793         case F_SETLKW:
3794         case F_OFD_GETLK:
3795         case F_OFD_SETLK:
3796         case F_OFD_SETLKW:
3797 #if BITS_PER_LONG == 32
3798         case F_GETLK64:
3799         case F_SETLK64:
3800         case F_SETLKW64:
3801 #endif
3802                 err = file_has_perm(cred, file, FILE__LOCK);
3803                 break;
3804         }
3805
3806         return err;
3807 }
3808
3809 static void selinux_file_set_fowner(struct file *file)
3810 {
3811         struct file_security_struct *fsec;
3812
3813         fsec = selinux_file(file);
3814         fsec->fown_sid = current_sid();
3815 }
3816
3817 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3818                                        struct fown_struct *fown, int signum)
3819 {
3820         struct file *file;
3821         u32 sid = task_sid(tsk);
3822         u32 perm;
3823         struct file_security_struct *fsec;
3824
3825         /* struct fown_struct is never outside the context of a struct file */
3826         file = container_of(fown, struct file, f_owner);
3827
3828         fsec = selinux_file(file);
3829
3830         if (!signum)
3831                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3832         else
3833                 perm = signal_to_av(signum);
3834
3835         return avc_has_perm(&selinux_state,
3836                             fsec->fown_sid, sid,
3837                             SECCLASS_PROCESS, perm, NULL);
3838 }
3839
3840 static int selinux_file_receive(struct file *file)
3841 {
3842         const struct cred *cred = current_cred();
3843
3844         return file_has_perm(cred, file, file_to_av(file));
3845 }
3846
3847 static int selinux_file_open(struct file *file)
3848 {
3849         struct file_security_struct *fsec;
3850         struct inode_security_struct *isec;
3851
3852         fsec = selinux_file(file);
3853         isec = inode_security(file_inode(file));
3854         /*
3855          * Save inode label and policy sequence number
3856          * at open-time so that selinux_file_permission
3857          * can determine whether revalidation is necessary.
3858          * Task label is already saved in the file security
3859          * struct as its SID.
3860          */
3861         fsec->isid = isec->sid;
3862         fsec->pseqno = avc_policy_seqno(&selinux_state);
3863         /*
3864          * Since the inode label or policy seqno may have changed
3865          * between the selinux_inode_permission check and the saving
3866          * of state above, recheck that access is still permitted.
3867          * Otherwise, access might never be revalidated against the
3868          * new inode label or new policy.
3869          * This check is not redundant - do not remove.
3870          */
3871         return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3872 }
3873
3874 /* task security operations */
3875
3876 static int selinux_task_alloc(struct task_struct *task,
3877                               unsigned long clone_flags)
3878 {
3879         u32 sid = current_sid();
3880
3881         return avc_has_perm(&selinux_state,
3882                             sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3883 }
3884
3885 /*
3886  * prepare a new set of credentials for modification
3887  */
3888 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3889                                 gfp_t gfp)
3890 {
3891         const struct task_security_struct *old_tsec = selinux_cred(old);
3892         struct task_security_struct *tsec = selinux_cred(new);
3893
3894         *tsec = *old_tsec;
3895         return 0;
3896 }
3897
3898 /*
3899  * transfer the SELinux data to a blank set of creds
3900  */
3901 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3902 {
3903         const struct task_security_struct *old_tsec = selinux_cred(old);
3904         struct task_security_struct *tsec = selinux_cred(new);
3905
3906         *tsec = *old_tsec;
3907 }
3908
3909 static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3910 {
3911         *secid = cred_sid(c);
3912 }
3913
3914 /*
3915  * set the security data for a kernel service
3916  * - all the creation contexts are set to unlabelled
3917  */
3918 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3919 {
3920         struct task_security_struct *tsec = selinux_cred(new);
3921         u32 sid = current_sid();
3922         int ret;
3923
3924         ret = avc_has_perm(&selinux_state,
3925                            sid, secid,
3926                            SECCLASS_KERNEL_SERVICE,
3927                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3928                            NULL);
3929         if (ret == 0) {
3930                 tsec->sid = secid;
3931                 tsec->create_sid = 0;
3932                 tsec->keycreate_sid = 0;
3933                 tsec->sockcreate_sid = 0;
3934         }
3935         return ret;
3936 }
3937
3938 /*
3939  * set the file creation context in a security record to the same as the
3940  * objective context of the specified inode
3941  */
3942 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3943 {
3944         struct inode_security_struct *isec = inode_security(inode);
3945         struct task_security_struct *tsec = selinux_cred(new);
3946         u32 sid = current_sid();
3947         int ret;
3948
3949         ret = avc_has_perm(&selinux_state,
3950                            sid, isec->sid,
3951                            SECCLASS_KERNEL_SERVICE,
3952                            KERNEL_SERVICE__CREATE_FILES_AS,
3953                            NULL);
3954
3955         if (ret == 0)
3956                 tsec->create_sid = isec->sid;
3957         return ret;
3958 }
3959
3960 static int selinux_kernel_module_request(char *kmod_name)
3961 {
3962         struct common_audit_data ad;
3963
3964         ad.type = LSM_AUDIT_DATA_KMOD;
3965         ad.u.kmod_name = kmod_name;
3966
3967         return avc_has_perm(&selinux_state,
3968                             current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
3969                             SYSTEM__MODULE_REQUEST, &ad);
3970 }
3971
3972 static int selinux_kernel_module_from_file(struct file *file)
3973 {
3974         struct common_audit_data ad;
3975         struct inode_security_struct *isec;
3976         struct file_security_struct *fsec;
3977         u32 sid = current_sid();
3978         int rc;
3979
3980         /* init_module */
3981         if (file == NULL)
3982                 return avc_has_perm(&selinux_state,
3983                                     sid, sid, SECCLASS_SYSTEM,
3984                                         SYSTEM__MODULE_LOAD, NULL);
3985
3986         /* finit_module */
3987
3988         ad.type = LSM_AUDIT_DATA_FILE;
3989         ad.u.file = file;
3990
3991         fsec = selinux_file(file);
3992         if (sid != fsec->sid) {
3993                 rc = avc_has_perm(&selinux_state,
3994                                   sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
3995                 if (rc)
3996                         return rc;
3997         }
3998
3999         isec = inode_security(file_inode(file));
4000         return avc_has_perm(&selinux_state,
4001                             sid, isec->sid, SECCLASS_SYSTEM,
4002                                 SYSTEM__MODULE_LOAD, &ad);
4003 }
4004
4005 static int selinux_kernel_read_file(struct file *file,
4006                                     enum kernel_read_file_id id)
4007 {
4008         int rc = 0;
4009
4010         switch (id) {
4011         case READING_MODULE:
4012                 rc = selinux_kernel_module_from_file(file);
4013                 break;
4014         default:
4015                 break;
4016         }
4017
4018         return rc;
4019 }
4020
4021 static int selinux_kernel_load_data(enum kernel_load_data_id id)
4022 {
4023         int rc = 0;
4024
4025         switch (id) {
4026         case LOADING_MODULE:
4027                 rc = selinux_kernel_module_from_file(NULL);
4028         default:
4029                 break;
4030         }
4031
4032         return rc;
4033 }
4034
4035 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4036 {
4037         return avc_has_perm(&selinux_state,
4038                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4039                             PROCESS__SETPGID, NULL);
4040 }
4041
4042 static int selinux_task_getpgid(struct task_struct *p)
4043 {
4044         return avc_has_perm(&selinux_state,
4045                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4046                             PROCESS__GETPGID, NULL);
4047 }
4048
4049 static int selinux_task_getsid(struct task_struct *p)
4050 {
4051         return avc_has_perm(&selinux_state,
4052                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4053                             PROCESS__GETSESSION, NULL);
4054 }
4055
4056 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
4057 {
4058         *secid = task_sid(p);
4059 }
4060
4061 static int selinux_task_setnice(struct task_struct *p, int nice)
4062 {
4063         return avc_has_perm(&selinux_state,
4064                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4065                             PROCESS__SETSCHED, NULL);
4066 }
4067
4068 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4069 {
4070         return avc_has_perm(&selinux_state,
4071                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4072                             PROCESS__SETSCHED, NULL);
4073 }
4074
4075 static int selinux_task_getioprio(struct task_struct *p)
4076 {
4077         return avc_has_perm(&selinux_state,
4078                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4079                             PROCESS__GETSCHED, NULL);
4080 }
4081
4082 static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4083                                 unsigned int flags)
4084 {
4085         u32 av = 0;
4086
4087         if (!flags)
4088                 return 0;
4089         if (flags & LSM_PRLIMIT_WRITE)
4090                 av |= PROCESS__SETRLIMIT;
4091         if (flags & LSM_PRLIMIT_READ)
4092                 av |= PROCESS__GETRLIMIT;
4093         return avc_has_perm(&selinux_state,
4094                             cred_sid(cred), cred_sid(tcred),
4095                             SECCLASS_PROCESS, av, NULL);
4096 }
4097
4098 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4099                 struct rlimit *new_rlim)
4100 {
4101         struct rlimit *old_rlim = p->signal->rlim + resource;
4102
4103         /* Control the ability to change the hard limit (whether
4104            lowering or raising it), so that the hard limit can
4105            later be used as a safe reset point for the soft limit
4106            upon context transitions.  See selinux_bprm_committing_creds. */
4107         if (old_rlim->rlim_max != new_rlim->rlim_max)
4108                 return avc_has_perm(&selinux_state,
4109                                     current_sid(), task_sid(p),
4110                                     SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4111
4112         return 0;
4113 }
4114
4115 static int selinux_task_setscheduler(struct task_struct *p)
4116 {
4117         return avc_has_perm(&selinux_state,
4118                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4119                             PROCESS__SETSCHED, NULL);
4120 }
4121
4122 static int selinux_task_getscheduler(struct task_struct *p)
4123 {
4124         return avc_has_perm(&selinux_state,
4125                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4126                             PROCESS__GETSCHED, NULL);
4127 }
4128
4129 static int selinux_task_movememory(struct task_struct *p)
4130 {
4131         return avc_has_perm(&selinux_state,
4132                             current_sid(), task_sid(p), SECCLASS_PROCESS,
4133                             PROCESS__SETSCHED, NULL);
4134 }
4135
4136 static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4137                                 int sig, const struct cred *cred)
4138 {
4139         u32 secid;
4140         u32 perm;
4141
4142         if (!sig)
4143                 perm = PROCESS__SIGNULL; /* null signal; existence test */
4144         else
4145                 perm = signal_to_av(sig);
4146         if (!cred)
4147                 secid = current_sid();
4148         else
4149                 secid = cred_sid(cred);
4150         return avc_has_perm(&selinux_state,
4151                             secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
4152 }
4153
4154 static void selinux_task_to_inode(struct task_struct *p,
4155                                   struct inode *inode)
4156 {
4157         struct inode_security_struct *isec = selinux_inode(inode);
4158         u32 sid = task_sid(p);
4159
4160         spin_lock(&isec->lock);
4161         isec->sclass = inode_mode_to_security_class(inode->i_mode);
4162         isec->sid = sid;
4163         isec->initialized = LABEL_INITIALIZED;
4164         spin_unlock(&isec->lock);
4165 }
4166
4167 /* Returns error only if unable to parse addresses */
4168 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4169                         struct common_audit_data *ad, u8 *proto)
4170 {
4171         int offset, ihlen, ret = -EINVAL;
4172         struct iphdr _iph, *ih;
4173
4174         offset = skb_network_offset(skb);
4175         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4176         if (ih == NULL)
4177                 goto out;
4178
4179         ihlen = ih->ihl * 4;
4180         if (ihlen < sizeof(_iph))
4181                 goto out;
4182
4183         ad->u.net->v4info.saddr = ih->saddr;
4184         ad->u.net->v4info.daddr = ih->daddr;
4185         ret = 0;
4186
4187         if (proto)
4188                 *proto = ih->protocol;
4189
4190         switch (ih->protocol) {
4191         case IPPROTO_TCP: {
4192                 struct tcphdr _tcph, *th;
4193
4194                 if (ntohs(ih->frag_off) & IP_OFFSET)
4195                         break;
4196
4197                 offset += ihlen;
4198                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4199                 if (th == NULL)
4200                         break;
4201
4202                 ad->u.net->sport = th->source;
4203                 ad->u.net->dport = th->dest;
4204                 break;
4205         }
4206
4207         case IPPROTO_UDP: {
4208                 struct udphdr _udph, *uh;
4209
4210                 if (ntohs(ih->frag_off) & IP_OFFSET)
4211                         break;
4212
4213                 offset += ihlen;
4214                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4215                 if (uh == NULL)
4216                         break;
4217
4218                 ad->u.net->sport = uh->source;
4219                 ad->u.net->dport = uh->dest;
4220                 break;
4221         }
4222
4223         case IPPROTO_DCCP: {
4224                 struct dccp_hdr _dccph, *dh;
4225
4226                 if (ntohs(ih->frag_off) & IP_OFFSET)
4227                         break;
4228
4229                 offset += ihlen;
4230                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4231                 if (dh == NULL)
4232                         break;
4233
4234                 ad->u.net->sport = dh->dccph_sport;
4235                 ad->u.net->dport = dh->dccph_dport;
4236                 break;
4237         }
4238
4239 #if IS_ENABLED(CONFIG_IP_SCTP)
4240         case IPPROTO_SCTP: {
4241                 struct sctphdr _sctph, *sh;
4242
4243                 if (ntohs(ih->frag_off) & IP_OFFSET)
4244                         break;
4245
4246                 offset += ihlen;
4247                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4248                 if (sh == NULL)
4249                         break;
4250
4251                 ad->u.net->sport = sh->source;
4252                 ad->u.net->dport = sh->dest;
4253                 break;
4254         }
4255 #endif
4256         default:
4257                 break;
4258         }
4259 out:
4260         return ret;
4261 }
4262
4263 #if IS_ENABLED(CONFIG_IPV6)
4264
4265 /* Returns error only if unable to parse addresses */
4266 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4267                         struct common_audit_data *ad, u8 *proto)
4268 {
4269         u8 nexthdr;
4270         int ret = -EINVAL, offset;
4271         struct ipv6hdr _ipv6h, *ip6;
4272         __be16 frag_off;
4273
4274         offset = skb_network_offset(skb);
4275         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4276         if (ip6 == NULL)
4277                 goto out;
4278
4279         ad->u.net->v6info.saddr = ip6->saddr;
4280         ad->u.net->v6info.daddr = ip6->daddr;
4281         ret = 0;
4282
4283         nexthdr = ip6->nexthdr;
4284         offset += sizeof(_ipv6h);
4285         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4286         if (offset < 0)
4287                 goto out;
4288
4289         if (proto)
4290                 *proto = nexthdr;
4291
4292         switch (nexthdr) {
4293         case IPPROTO_TCP: {
4294                 struct tcphdr _tcph, *th;
4295
4296                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4297                 if (th == NULL)
4298                         break;
4299
4300                 ad->u.net->sport = th->source;
4301                 ad->u.net->dport = th->dest;
4302                 break;
4303         }
4304
4305         case IPPROTO_UDP: {
4306                 struct udphdr _udph, *uh;
4307
4308                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4309                 if (uh == NULL)
4310                         break;
4311
4312                 ad->u.net->sport = uh->source;
4313                 ad->u.net->dport = uh->dest;
4314                 break;
4315         }
4316
4317         case IPPROTO_DCCP: {
4318                 struct dccp_hdr _dccph, *dh;
4319
4320                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4321                 if (dh == NULL)
4322                         break;
4323
4324                 ad->u.net->sport = dh->dccph_sport;
4325                 ad->u.net->dport = dh->dccph_dport;
4326                 break;
4327         }
4328
4329 #if IS_ENABLED(CONFIG_IP_SCTP)
4330         case IPPROTO_SCTP: {
4331                 struct sctphdr _sctph, *sh;
4332
4333                 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4334                 if (sh == NULL)
4335                         break;
4336
4337                 ad->u.net->sport = sh->source;
4338                 ad->u.net->dport = sh->dest;
4339                 break;
4340         }
4341 #endif
4342         /* includes fragments */
4343         default:
4344                 break;
4345         }
4346 out:
4347         return ret;
4348 }
4349
4350 #endif /* IPV6 */
4351
4352 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4353                              char **_addrp, int src, u8 *proto)
4354 {
4355         char *addrp;
4356         int ret;
4357
4358         switch (ad->u.net->family) {
4359         case PF_INET:
4360                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4361                 if (ret)
4362                         goto parse_error;
4363                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4364                                        &ad->u.net->v4info.daddr);
4365                 goto okay;
4366
4367 #if IS_ENABLED(CONFIG_IPV6)
4368         case PF_INET6:
4369                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4370                 if (ret)
4371                         goto parse_error;
4372                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4373                                        &ad->u.net->v6info.daddr);
4374                 goto okay;
4375 #endif  /* IPV6 */
4376         default:
4377                 addrp = NULL;
4378                 goto okay;
4379         }
4380
4381 parse_error:
4382         pr_warn(
4383                "SELinux: failure in selinux_parse_skb(),"
4384                " unable to parse packet\n");
4385         return ret;
4386
4387 okay:
4388         if (_addrp)
4389                 *_addrp = addrp;
4390         return 0;
4391 }
4392
4393 /**
4394  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4395  * @skb: the packet
4396  * @family: protocol family
4397  * @sid: the packet's peer label SID
4398  *
4399  * Description:
4400  * Check the various different forms of network peer labeling and determine
4401  * the peer label/SID for the packet; most of the magic actually occurs in
4402  * the security server function security_net_peersid_cmp().  The function
4403  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4404  * or -EACCES if @sid is invalid due to inconsistencies with the different
4405  * peer labels.
4406  *
4407  */
4408 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4409 {
4410         int err;
4411         u32 xfrm_sid;
4412         u32 nlbl_sid;
4413         u32 nlbl_type;
4414
4415         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4416         if (unlikely(err))
4417                 return -EACCES;
4418         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4419         if (unlikely(err))
4420                 return -EACCES;
4421
4422         err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4423                                            nlbl_type, xfrm_sid, sid);
4424         if (unlikely(err)) {
4425                 pr_warn(
4426                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4427                        " unable to determine packet's peer label\n");
4428                 return -EACCES;
4429         }
4430
4431         return 0;
4432 }
4433
4434 /**
4435  * selinux_conn_sid - Determine the child socket label for a connection
4436  * @sk_sid: the parent socket's SID
4437  * @skb_sid: the packet's SID
4438  * @conn_sid: the resulting connection SID
4439  *
4440  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4441  * combined with the MLS information from @skb_sid in order to create
4442  * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
4443  * of @sk_sid.  Returns zero on success, negative values on failure.
4444  *
4445  */
4446 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4447 {
4448         int err = 0;
4449
4450         if (skb_sid != SECSID_NULL)
4451                 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4452                                             conn_sid);
4453         else
4454                 *conn_sid = sk_sid;
4455
4456         return err;
4457 }
4458
4459 /* socket security operations */
4460
4461 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4462                                  u16 secclass, u32 *socksid)
4463 {
4464         if (tsec->sockcreate_sid > SECSID_NULL) {
4465                 *socksid = tsec->sockcreate_sid;
4466                 return 0;
4467         }
4468
4469         return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4470                                        secclass, NULL, socksid);
4471 }
4472
4473 static int sock_has_perm(struct sock *sk, u32 perms)
4474 {
4475         struct sk_security_struct *sksec = sk->sk_security;
4476         struct common_audit_data ad;
4477         struct lsm_network_audit net = {0,};
4478
4479         if (sksec->sid == SECINITSID_KERNEL)
4480                 return 0;
4481
4482         ad.type = LSM_AUDIT_DATA_NET;
4483         ad.u.net = &net;
4484         ad.u.net->sk = sk;
4485
4486         return avc_has_perm(&selinux_state,
4487                             current_sid(), sksec->sid, sksec->sclass, perms,
4488                             &ad);
4489 }
4490
4491 static int selinux_socket_create(int family, int type,
4492                                  int protocol, int kern)
4493 {
4494         const struct task_security_struct *tsec = selinux_cred(current_cred());
4495         u32 newsid;
4496         u16 secclass;
4497         int rc;
4498
4499         if (kern)
4500                 return 0;
4501
4502         secclass = socket_type_to_security_class(family, type, protocol);
4503         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4504         if (rc)
4505                 return rc;
4506
4507         return avc_has_perm(&selinux_state,
4508                             tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4509 }
4510
4511 static int selinux_socket_post_create(struct socket *sock, int family,
4512                                       int type, int protocol, int kern)
4513 {
4514         const struct task_security_struct *tsec = selinux_cred(current_cred());
4515         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4516         struct sk_security_struct *sksec;
4517         u16 sclass = socket_type_to_security_class(family, type, protocol);
4518         u32 sid = SECINITSID_KERNEL;
4519         int err = 0;
4520
4521         if (!kern) {
4522                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4523                 if (err)
4524                         return err;
4525         }
4526
4527         isec->sclass = sclass;
4528         isec->sid = sid;
4529         isec->initialized = LABEL_INITIALIZED;
4530
4531         if (sock->sk) {
4532                 sksec = sock->sk->sk_security;
4533                 sksec->sclass = sclass;
4534                 sksec->sid = sid;
4535                 /* Allows detection of the first association on this socket */
4536                 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4537                         sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4538
4539                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4540         }
4541
4542         return err;
4543 }
4544
4545 static int selinux_socket_socketpair(struct socket *socka,
4546                                      struct socket *sockb)
4547 {
4548         struct sk_security_struct *sksec_a = socka->sk->sk_security;
4549         struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4550
4551         sksec_a->peer_sid = sksec_b->sid;
4552         sksec_b->peer_sid = sksec_a->sid;
4553
4554         return 0;
4555 }
4556
4557 /* Range of port numbers used to automatically bind.
4558    Need to determine whether we should perform a name_bind
4559    permission check between the socket and the port number. */
4560
4561 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4562 {
4563         struct sock *sk = sock->sk;
4564         struct sk_security_struct *sksec = sk->sk_security;
4565         u16 family;
4566         int err;
4567
4568         err = sock_has_perm(sk, SOCKET__BIND);
4569         if (err)
4570                 goto out;
4571
4572         /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4573         family = sk->sk_family;
4574         if (family == PF_INET || family == PF_INET6) {
4575                 char *addrp;
4576                 struct common_audit_data ad;
4577                 struct lsm_network_audit net = {0,};
4578                 struct sockaddr_in *addr4 = NULL;
4579                 struct sockaddr_in6 *addr6 = NULL;
4580                 u16 family_sa;
4581                 unsigned short snum;
4582                 u32 sid, node_perm;
4583
4584                 /*
4585                  * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4586                  * that validates multiple binding addresses. Because of this
4587                  * need to check address->sa_family as it is possible to have
4588                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4589                  */
4590                 if (addrlen < offsetofend(struct sockaddr, sa_family))
4591                         return -EINVAL;
4592                 family_sa = address->sa_family;
4593                 switch (family_sa) {
4594                 case AF_UNSPEC:
4595                 case AF_INET:
4596                         if (addrlen < sizeof(struct sockaddr_in))
4597                                 return -EINVAL;
4598                         addr4 = (struct sockaddr_in *)address;
4599                         if (family_sa == AF_UNSPEC) {
4600                                 /* see __inet_bind(), we only want to allow
4601                                  * AF_UNSPEC if the address is INADDR_ANY
4602                                  */
4603                                 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4604                                         goto err_af;
4605                                 family_sa = AF_INET;
4606                         }
4607                         snum = ntohs(addr4->sin_port);
4608                         addrp = (char *)&addr4->sin_addr.s_addr;
4609                         break;
4610                 case AF_INET6:
4611                         if (addrlen < SIN6_LEN_RFC2133)
4612                                 return -EINVAL;
4613                         addr6 = (struct sockaddr_in6 *)address;
4614                         snum = ntohs(addr6->sin6_port);
4615                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4616                         break;
4617                 default:
4618                         goto err_af;
4619                 }
4620
4621                 ad.type = LSM_AUDIT_DATA_NET;
4622                 ad.u.net = &net;
4623                 ad.u.net->sport = htons(snum);
4624                 ad.u.net->family = family_sa;
4625
4626                 if (snum) {
4627                         int low, high;
4628
4629                         inet_get_local_port_range(sock_net(sk), &low, &high);
4630
4631                         if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4632                             snum < low || snum > high) {
4633                                 err = sel_netport_sid(sk->sk_protocol,
4634                                                       snum, &sid);
4635                                 if (err)
4636                                         goto out;
4637                                 err = avc_has_perm(&selinux_state,
4638                                                    sksec->sid, sid,
4639                                                    sksec->sclass,
4640                                                    SOCKET__NAME_BIND, &ad);
4641                                 if (err)
4642                                         goto out;
4643                         }
4644                 }
4645
4646                 switch (sksec->sclass) {
4647                 case SECCLASS_TCP_SOCKET:
4648                         node_perm = TCP_SOCKET__NODE_BIND;
4649                         break;
4650
4651                 case SECCLASS_UDP_SOCKET:
4652                         node_perm = UDP_SOCKET__NODE_BIND;
4653                         break;
4654
4655                 case SECCLASS_DCCP_SOCKET:
4656                         node_perm = DCCP_SOCKET__NODE_BIND;
4657                         break;
4658
4659                 case SECCLASS_SCTP_SOCKET:
4660                         node_perm = SCTP_SOCKET__NODE_BIND;
4661                         break;
4662
4663                 default:
4664                         node_perm = RAWIP_SOCKET__NODE_BIND;
4665                         break;
4666                 }
4667
4668                 err = sel_netnode_sid(addrp, family_sa, &sid);
4669                 if (err)
4670                         goto out;
4671
4672                 if (family_sa == AF_INET)
4673                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4674                 else
4675                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4676
4677                 err = avc_has_perm(&selinux_state,
4678                                    sksec->sid, sid,
4679                                    sksec->sclass, node_perm, &ad);
4680                 if (err)
4681                         goto out;
4682         }
4683 out:
4684         return err;
4685 err_af:
4686         /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4687         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4688                 return -EINVAL;
4689         return -EAFNOSUPPORT;
4690 }
4691
4692 /* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4693  * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4694  */
4695 static int selinux_socket_connect_helper(struct socket *sock,
4696                                          struct sockaddr *address, int addrlen)
4697 {
4698         struct sock *sk = sock->sk;
4699         struct sk_security_struct *sksec = sk->sk_security;
4700         int err;
4701
4702         err = sock_has_perm(sk, SOCKET__CONNECT);
4703         if (err)
4704                 return err;
4705         if (addrlen < offsetofend(struct sockaddr, sa_family))
4706                 return -EINVAL;
4707
4708         /* connect(AF_UNSPEC) has special handling, as it is a documented
4709          * way to disconnect the socket
4710          */
4711         if (address->sa_family == AF_UNSPEC)
4712                 return 0;
4713
4714         /*
4715          * If a TCP, DCCP or SCTP socket, check name_connect permission
4716          * for the port.
4717          */
4718         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4719             sksec->sclass == SECCLASS_DCCP_SOCKET ||
4720             sksec->sclass == SECCLASS_SCTP_SOCKET) {
4721                 struct common_audit_data ad;
4722                 struct lsm_network_audit net = {0,};
4723                 struct sockaddr_in *addr4 = NULL;
4724                 struct sockaddr_in6 *addr6 = NULL;
4725                 unsigned short snum;
4726                 u32 sid, perm;
4727
4728                 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4729                  * that validates multiple connect addresses. Because of this
4730                  * need to check address->sa_family as it is possible to have
4731                  * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4732                  */
4733                 switch (address->sa_family) {
4734                 case AF_INET:
4735                         addr4 = (struct sockaddr_in *)address;
4736                         if (addrlen < sizeof(struct sockaddr_in))
4737                                 return -EINVAL;
4738                         snum = ntohs(addr4->sin_port);
4739                         break;
4740                 case AF_INET6:
4741                         addr6 = (struct sockaddr_in6 *)address;
4742                         if (addrlen < SIN6_LEN_RFC2133)
4743                                 return -EINVAL;
4744                         snum = ntohs(addr6->sin6_port);
4745                         break;
4746                 default:
4747                         /* Note that SCTP services expect -EINVAL, whereas
4748                          * others expect -EAFNOSUPPORT.
4749                          */
4750                         if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4751                                 return -EINVAL;
4752                         else
4753                                 return -EAFNOSUPPORT;
4754                 }
4755
4756                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4757                 if (err)
4758                         return err;
4759
4760                 switch (sksec->sclass) {
4761                 case SECCLASS_TCP_SOCKET:
4762                         perm = TCP_SOCKET__NAME_CONNECT;
4763                         break;
4764                 case SECCLASS_DCCP_SOCKET:
4765                         perm = DCCP_SOCKET__NAME_CONNECT;
4766                         break;
4767                 case SECCLASS_SCTP_SOCKET:
4768                         perm = SCTP_SOCKET__NAME_CONNECT;
4769                         break;
4770                 }
4771
4772                 ad.type = LSM_AUDIT_DATA_NET;
4773                 ad.u.net = &net;
4774                 ad.u.net->dport = htons(snum);
4775                 ad.u.net->family = address->sa_family;
4776                 err = avc_has_perm(&selinux_state,
4777                                    sksec->sid, sid, sksec->sclass, perm, &ad);
4778                 if (err)
4779                         return err;
4780         }
4781
4782         return 0;
4783 }
4784
4785 /* Supports connect(2), see comments in selinux_socket_connect_helper() */
4786 static int selinux_socket_connect(struct socket *sock,
4787                                   struct sockaddr *address, int addrlen)
4788 {
4789         int err;
4790         struct sock *sk = sock->sk;
4791
4792         err = selinux_socket_connect_helper(sock, address, addrlen);
4793         if (err)
4794                 return err;
4795
4796         return selinux_netlbl_socket_connect(sk, address);
4797 }
4798
4799 static int selinux_socket_listen(struct socket *sock, int backlog)
4800 {
4801         return sock_has_perm(sock->sk, SOCKET__LISTEN);
4802 }
4803
4804 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4805 {
4806         int err;
4807         struct inode_security_struct *isec;
4808         struct inode_security_struct *newisec;
4809         u16 sclass;
4810         u32 sid;
4811
4812         err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4813         if (err)
4814                 return err;
4815
4816         isec = inode_security_novalidate(SOCK_INODE(sock));
4817         spin_lock(&isec->lock);
4818         sclass = isec->sclass;
4819         sid = isec->sid;
4820         spin_unlock(&isec->lock);
4821
4822         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4823         newisec->sclass = sclass;
4824         newisec->sid = sid;
4825         newisec->initialized = LABEL_INITIALIZED;
4826
4827         return 0;
4828 }
4829
4830 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4831                                   int size)
4832 {
4833         return sock_has_perm(sock->sk, SOCKET__WRITE);
4834 }
4835
4836 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4837                                   int size, int flags)
4838 {
4839         return sock_has_perm(sock->sk, SOCKET__READ);
4840 }
4841
4842 static int selinux_socket_getsockname(struct socket *sock)
4843 {
4844         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4845 }
4846
4847 static int selinux_socket_getpeername(struct socket *sock)
4848 {
4849         return sock_has_perm(sock->sk, SOCKET__GETATTR);
4850 }
4851
4852 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4853 {
4854         int err;
4855
4856         err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4857         if (err)
4858                 return err;
4859
4860         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4861 }
4862
4863 static int selinux_socket_getsockopt(struct socket *sock, int level,
4864                                      int optname)
4865 {
4866         return sock_has_perm(sock->sk, SOCKET__GETOPT);
4867 }
4868
4869 static int selinux_socket_shutdown(struct socket *sock, int how)
4870 {
4871         return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4872 }
4873
4874 static int selinux_socket_unix_stream_connect(struct sock *sock,
4875                                               struct sock *other,
4876                                               struct sock *newsk)
4877 {
4878         struct sk_security_struct *sksec_sock = sock->sk_security;
4879         struct sk_security_struct *sksec_other = other->sk_security;
4880         struct sk_security_struct *sksec_new = newsk->sk_security;
4881         struct common_audit_data ad;
4882         struct lsm_network_audit net = {0,};
4883         int err;
4884
4885         ad.type = LSM_AUDIT_DATA_NET;
4886         ad.u.net = &net;
4887         ad.u.net->sk = other;
4888
4889         err = avc_has_perm(&selinux_state,
4890                            sksec_sock->sid, sksec_other->sid,
4891                            sksec_other->sclass,
4892                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4893         if (err)
4894                 return err;
4895
4896         /* server child socket */
4897         sksec_new->peer_sid = sksec_sock->sid;
4898         err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4899                                     sksec_sock->sid, &sksec_new->sid);
4900         if (err)
4901                 return err;
4902
4903         /* connecting socket */
4904         sksec_sock->peer_sid = sksec_new->sid;
4905
4906         return 0;
4907 }
4908
4909 static int selinux_socket_unix_may_send(struct socket *sock,
4910                                         struct socket *other)
4911 {
4912         struct sk_security_struct *ssec = sock->sk->sk_security;
4913         struct sk_security_struct *osec = other->sk->sk_security;
4914         struct common_audit_data ad;
4915         struct lsm_network_audit net = {0,};
4916
4917         ad.type = LSM_AUDIT_DATA_NET;
4918         ad.u.net = &net;
4919         ad.u.net->sk = other->sk;
4920
4921         return avc_has_perm(&selinux_state,
4922                             ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4923                             &ad);
4924 }
4925
4926 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4927                                     char *addrp, u16 family, u32 peer_sid,
4928                                     struct common_audit_data *ad)
4929 {
4930         int err;
4931         u32 if_sid;
4932         u32 node_sid;
4933
4934         err = sel_netif_sid(ns, ifindex, &if_sid);
4935         if (err)
4936                 return err;
4937         err = avc_has_perm(&selinux_state,
4938                            peer_sid, if_sid,
4939                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4940         if (err)
4941                 return err;
4942
4943         err = sel_netnode_sid(addrp, family, &node_sid);
4944         if (err)
4945                 return err;
4946         return avc_has_perm(&selinux_state,
4947                             peer_sid, node_sid,
4948                             SECCLASS_NODE, NODE__RECVFROM, ad);
4949 }
4950
4951 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4952                                        u16 family)
4953 {
4954         int err = 0;
4955         struct sk_security_struct *sksec = sk->sk_security;
4956         u32 sk_sid = sksec->sid;
4957         struct common_audit_data ad;
4958         struct lsm_network_audit net = {0,};
4959         char *addrp;
4960
4961         ad.type = LSM_AUDIT_DATA_NET;
4962         ad.u.net = &net;
4963         ad.u.net->netif = skb->skb_iif;
4964         ad.u.net->family = family;
4965         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4966         if (err)
4967                 return err;
4968
4969         if (selinux_secmark_enabled()) {
4970                 err = avc_has_perm(&selinux_state,
4971                                    sk_sid, skb->secmark, SECCLASS_PACKET,
4972                                    PACKET__RECV, &ad);
4973                 if (err)
4974                         return err;
4975         }
4976
4977         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4978         if (err)
4979                 return err;
4980         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4981
4982         return err;
4983 }
4984
4985 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4986 {
4987         int err;
4988         struct sk_security_struct *sksec = sk->sk_security;
4989         u16 family = sk->sk_family;
4990         u32 sk_sid = sksec->sid;
4991         struct common_audit_data ad;
4992         struct lsm_network_audit net = {0,};
4993         char *addrp;
4994         u8 secmark_active;
4995         u8 peerlbl_active;
4996
4997         if (family != PF_INET && family != PF_INET6)
4998                 return 0;
4999
5000         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5001         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5002                 family = PF_INET;
5003
5004         /* If any sort of compatibility mode is enabled then handoff processing
5005          * to the selinux_sock_rcv_skb_compat() function to deal with the
5006          * special handling.  We do this in an attempt to keep this function
5007          * as fast and as clean as possible. */
5008         if (!selinux_policycap_netpeer())
5009                 return selinux_sock_rcv_skb_compat(sk, skb, family);
5010
5011         secmark_active = selinux_secmark_enabled();
5012         peerlbl_active = selinux_peerlbl_enabled();
5013         if (!secmark_active && !peerlbl_active)
5014                 return 0;
5015
5016         ad.type = LSM_AUDIT_DATA_NET;
5017         ad.u.net = &net;
5018         ad.u.net->netif = skb->skb_iif;
5019         ad.u.net->family = family;
5020         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5021         if (err)
5022                 return err;
5023
5024         if (peerlbl_active) {
5025                 u32 peer_sid;
5026
5027                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5028                 if (err)
5029                         return err;
5030                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5031                                                addrp, family, peer_sid, &ad);
5032                 if (err) {
5033                         selinux_netlbl_err(skb, family, err, 0);
5034                         return err;
5035                 }
5036                 err = avc_has_perm(&selinux_state,
5037                                    sk_sid, peer_sid, SECCLASS_PEER,
5038                                    PEER__RECV, &ad);
5039                 if (err) {
5040                         selinux_netlbl_err(skb, family, err, 0);
5041                         return err;
5042                 }
5043         }
5044
5045         if (secmark_active) {
5046                 err = avc_has_perm(&selinux_state,
5047                                    sk_sid, skb->secmark, SECCLASS_PACKET,
5048                                    PACKET__RECV, &ad);
5049                 if (err)
5050                         return err;
5051         }
5052
5053         return err;
5054 }
5055
5056 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
5057                                             int __user *optlen, unsigned len)
5058 {
5059         int err = 0;
5060         char *scontext;
5061         u32 scontext_len;
5062         struct sk_security_struct *sksec = sock->sk->sk_security;
5063         u32 peer_sid = SECSID_NULL;
5064
5065         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5066             sksec->sclass == SECCLASS_TCP_SOCKET ||
5067             sksec->sclass == SECCLASS_SCTP_SOCKET)
5068                 peer_sid = sksec->peer_sid;
5069         if (peer_sid == SECSID_NULL)
5070                 return -ENOPROTOOPT;
5071
5072         err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5073                                       &scontext_len);
5074         if (err)
5075                 return err;
5076
5077         if (scontext_len > len) {
5078                 err = -ERANGE;
5079                 goto out_len;
5080         }
5081
5082         if (copy_to_user(optval, scontext, scontext_len))
5083                 err = -EFAULT;
5084
5085 out_len:
5086         if (put_user(scontext_len, optlen))
5087                 err = -EFAULT;
5088         kfree(scontext);
5089         return err;
5090 }
5091
5092 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5093 {
5094         u32 peer_secid = SECSID_NULL;
5095         u16 family;
5096         struct inode_security_struct *isec;
5097
5098         if (skb && skb->protocol == htons(ETH_P_IP))
5099                 family = PF_INET;
5100         else if (skb && skb->protocol == htons(ETH_P_IPV6))
5101                 family = PF_INET6;
5102         else if (sock)
5103                 family = sock->sk->sk_family;
5104         else
5105                 goto out;
5106
5107         if (sock && family == PF_UNIX) {
5108                 isec = inode_security_novalidate(SOCK_INODE(sock));
5109                 peer_secid = isec->sid;
5110         } else if (skb)
5111                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5112
5113 out:
5114         *secid = peer_secid;
5115         if (peer_secid == SECSID_NULL)
5116                 return -EINVAL;
5117         return 0;
5118 }
5119
5120 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5121 {
5122         struct sk_security_struct *sksec;
5123
5124         sksec = kzalloc(sizeof(*sksec), priority);
5125         if (!sksec)
5126                 return -ENOMEM;
5127
5128         sksec->peer_sid = SECINITSID_UNLABELED;
5129         sksec->sid = SECINITSID_UNLABELED;
5130         sksec->sclass = SECCLASS_SOCKET;
5131         selinux_netlbl_sk_security_reset(sksec);
5132         sk->sk_security = sksec;
5133
5134         return 0;
5135 }
5136
5137 static void selinux_sk_free_security(struct sock *sk)
5138 {
5139         struct sk_security_struct *sksec = sk->sk_security;
5140
5141         sk->sk_security = NULL;
5142         selinux_netlbl_sk_security_free(sksec);
5143         kfree(sksec);
5144 }
5145
5146 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5147 {
5148         struct sk_security_struct *sksec = sk->sk_security;
5149         struct sk_security_struct *newsksec = newsk->sk_security;
5150
5151         newsksec->sid = sksec->sid;
5152         newsksec->peer_sid = sksec->peer_sid;
5153         newsksec->sclass = sksec->sclass;
5154
5155         selinux_netlbl_sk_security_reset(newsksec);
5156 }
5157
5158 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5159 {
5160         if (!sk)
5161                 *secid = SECINITSID_ANY_SOCKET;
5162         else {
5163                 struct sk_security_struct *sksec = sk->sk_security;
5164
5165                 *secid = sksec->sid;
5166         }
5167 }
5168
5169 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5170 {
5171         struct inode_security_struct *isec =
5172                 inode_security_novalidate(SOCK_INODE(parent));
5173         struct sk_security_struct *sksec = sk->sk_security;
5174
5175         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5176             sk->sk_family == PF_UNIX)
5177                 isec->sid = sksec->sid;
5178         sksec->sclass = isec->sclass;
5179 }
5180
5181 /* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5182  * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5183  * already present).
5184  */
5185 static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5186                                       struct sk_buff *skb)
5187 {
5188         struct sk_security_struct *sksec = ep->base.sk->sk_security;
5189         struct common_audit_data ad;
5190         struct lsm_network_audit net = {0,};
5191         u8 peerlbl_active;
5192         u32 peer_sid = SECINITSID_UNLABELED;
5193         u32 conn_sid;
5194         int err = 0;
5195
5196         if (!selinux_policycap_extsockclass())
5197                 return 0;
5198
5199         peerlbl_active = selinux_peerlbl_enabled();
5200
5201         if (peerlbl_active) {
5202                 /* This will return peer_sid = SECSID_NULL if there are
5203                  * no peer labels, see security_net_peersid_resolve().
5204                  */
5205                 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5206                                               &peer_sid);
5207                 if (err)
5208                         return err;
5209
5210                 if (peer_sid == SECSID_NULL)
5211                         peer_sid = SECINITSID_UNLABELED;
5212         }
5213
5214         if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5215                 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5216
5217                 /* Here as first association on socket. As the peer SID
5218                  * was allowed by peer recv (and the netif/node checks),
5219                  * then it is approved by policy and used as the primary
5220                  * peer SID for getpeercon(3).
5221                  */
5222                 sksec->peer_sid = peer_sid;
5223         } else if  (sksec->peer_sid != peer_sid) {
5224                 /* Other association peer SIDs are checked to enforce
5225                  * consistency among the peer SIDs.
5226                  */
5227                 ad.type = LSM_AUDIT_DATA_NET;
5228                 ad.u.net = &net;
5229                 ad.u.net->sk = ep->base.sk;
5230                 err = avc_has_perm(&selinux_state,
5231                                    sksec->peer_sid, peer_sid, sksec->sclass,
5232                                    SCTP_SOCKET__ASSOCIATION, &ad);
5233                 if (err)
5234                         return err;
5235         }
5236
5237         /* Compute the MLS component for the connection and store
5238          * the information in ep. This will be used by SCTP TCP type
5239          * sockets and peeled off connections as they cause a new
5240          * socket to be generated. selinux_sctp_sk_clone() will then
5241          * plug this into the new socket.
5242          */
5243         err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5244         if (err)
5245                 return err;
5246
5247         ep->secid = conn_sid;
5248         ep->peer_secid = peer_sid;
5249
5250         /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5251         return selinux_netlbl_sctp_assoc_request(ep, skb);
5252 }
5253
5254 /* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5255  * based on their @optname.
5256  */
5257 static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5258                                      struct sockaddr *address,
5259                                      int addrlen)
5260 {
5261         int len, err = 0, walk_size = 0;
5262         void *addr_buf;
5263         struct sockaddr *addr;
5264         struct socket *sock;
5265
5266         if (!selinux_policycap_extsockclass())
5267                 return 0;
5268
5269         /* Process one or more addresses that may be IPv4 or IPv6 */
5270         sock = sk->sk_socket;
5271         addr_buf = address;
5272
5273         while (walk_size < addrlen) {
5274                 if (walk_size + sizeof(sa_family_t) > addrlen)
5275                         return -EINVAL;
5276
5277                 addr = addr_buf;
5278                 switch (addr->sa_family) {
5279                 case AF_UNSPEC:
5280                 case AF_INET:
5281                         len = sizeof(struct sockaddr_in);
5282                         break;
5283                 case AF_INET6:
5284                         len = sizeof(struct sockaddr_in6);
5285                         break;
5286                 default:
5287                         return -EINVAL;
5288                 }
5289
5290                 if (walk_size + len > addrlen)
5291                         return -EINVAL;
5292
5293                 err = -EINVAL;
5294                 switch (optname) {
5295                 /* Bind checks */
5296                 case SCTP_PRIMARY_ADDR:
5297                 case SCTP_SET_PEER_PRIMARY_ADDR:
5298                 case SCTP_SOCKOPT_BINDX_ADD:
5299                         err = selinux_socket_bind(sock, addr, len);
5300                         break;
5301                 /* Connect checks */
5302                 case SCTP_SOCKOPT_CONNECTX:
5303                 case SCTP_PARAM_SET_PRIMARY:
5304                 case SCTP_PARAM_ADD_IP:
5305                 case SCTP_SENDMSG_CONNECT:
5306                         err = selinux_socket_connect_helper(sock, addr, len);
5307                         if (err)
5308                                 return err;
5309
5310                         /* As selinux_sctp_bind_connect() is called by the
5311                          * SCTP protocol layer, the socket is already locked,
5312                          * therefore selinux_netlbl_socket_connect_locked() is
5313                          * is called here. The situations handled are:
5314                          * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5315                          * whenever a new IP address is added or when a new
5316                          * primary address is selected.
5317                          * Note that an SCTP connect(2) call happens before
5318                          * the SCTP protocol layer and is handled via
5319                          * selinux_socket_connect().
5320                          */
5321                         err = selinux_netlbl_socket_connect_locked(sk, addr);
5322                         break;
5323                 }
5324
5325                 if (err)
5326                         return err;
5327
5328                 addr_buf += len;
5329                 walk_size += len;
5330         }
5331
5332         return 0;
5333 }
5334
5335 /* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5336 static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5337                                   struct sock *newsk)
5338 {
5339         struct sk_security_struct *sksec = sk->sk_security;
5340         struct sk_security_struct *newsksec = newsk->sk_security;
5341
5342         /* If policy does not support SECCLASS_SCTP_SOCKET then call
5343          * the non-sctp clone version.
5344          */
5345         if (!selinux_policycap_extsockclass())
5346                 return selinux_sk_clone_security(sk, newsk);
5347
5348         newsksec->sid = ep->secid;
5349         newsksec->peer_sid = ep->peer_secid;
5350         newsksec->sclass = sksec->sclass;
5351         selinux_netlbl_sctp_sk_clone(sk, newsk);
5352 }
5353
5354 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
5355                                      struct request_sock *req)
5356 {
5357         struct sk_security_struct *sksec = sk->sk_security;
5358         int err;
5359         u16 family = req->rsk_ops->family;
5360         u32 connsid;
5361         u32 peersid;
5362
5363         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5364         if (err)
5365                 return err;
5366         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5367         if (err)
5368                 return err;
5369         req->secid = connsid;
5370         req->peer_secid = peersid;
5371
5372         return selinux_netlbl_inet_conn_request(req, family);
5373 }
5374
5375 static void selinux_inet_csk_clone(struct sock *newsk,
5376                                    const struct request_sock *req)
5377 {
5378         struct sk_security_struct *newsksec = newsk->sk_security;
5379
5380         newsksec->sid = req->secid;
5381         newsksec->peer_sid = req->peer_secid;
5382         /* NOTE: Ideally, we should also get the isec->sid for the
5383            new socket in sync, but we don't have the isec available yet.
5384            So we will wait until sock_graft to do it, by which
5385            time it will have been created and available. */
5386
5387         /* We don't need to take any sort of lock here as we are the only
5388          * thread with access to newsksec */
5389         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5390 }
5391
5392 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5393 {
5394         u16 family = sk->sk_family;
5395         struct sk_security_struct *sksec = sk->sk_security;
5396
5397         /* handle mapped IPv4 packets arriving via IPv6 sockets */
5398         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5399                 family = PF_INET;
5400
5401         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5402 }
5403
5404 static int selinux_secmark_relabel_packet(u32 sid)
5405 {
5406         const struct task_security_struct *__tsec;
5407         u32 tsid;
5408
5409         __tsec = selinux_cred(current_cred());
5410         tsid = __tsec->sid;
5411
5412         return avc_has_perm(&selinux_state,
5413                             tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5414                             NULL);
5415 }
5416
5417 static void selinux_secmark_refcount_inc(void)
5418 {
5419         atomic_inc(&selinux_secmark_refcount);
5420 }
5421
5422 static void selinux_secmark_refcount_dec(void)
5423 {
5424         atomic_dec(&selinux_secmark_refcount);
5425 }
5426
5427 static void selinux_req_classify_flow(const struct request_sock *req,
5428                                       struct flowi *fl)
5429 {
5430         fl->flowi_secid = req->secid;
5431 }
5432
5433 static int selinux_tun_dev_alloc_security(void **security)
5434 {
5435         struct tun_security_struct *tunsec;
5436
5437         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5438         if (!tunsec)
5439                 return -ENOMEM;
5440         tunsec->sid = current_sid();
5441
5442         *security = tunsec;
5443         return 0;
5444 }
5445
5446 static void selinux_tun_dev_free_security(void *security)
5447 {
5448         kfree(security);
5449 }
5450
5451 static int selinux_tun_dev_create(void)
5452 {
5453         u32 sid = current_sid();
5454
5455         /* we aren't taking into account the "sockcreate" SID since the socket
5456          * that is being created here is not a socket in the traditional sense,
5457          * instead it is a private sock, accessible only to the kernel, and
5458          * representing a wide range of network traffic spanning multiple
5459          * connections unlike traditional sockets - check the TUN driver to
5460          * get a better understanding of why this socket is special */
5461
5462         return avc_has_perm(&selinux_state,
5463                             sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5464                             NULL);
5465 }
5466
5467 static int selinux_tun_dev_attach_queue(void *security)
5468 {
5469         struct tun_security_struct *tunsec = security;
5470
5471         return avc_has_perm(&selinux_state,
5472                             current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5473                             TUN_SOCKET__ATTACH_QUEUE, NULL);
5474 }
5475
5476 static int selinux_tun_dev_attach(struct sock *sk, void *security)
5477 {
5478         struct tun_security_struct *tunsec = security;
5479         struct sk_security_struct *sksec = sk->sk_security;
5480
5481         /* we don't currently perform any NetLabel based labeling here and it
5482          * isn't clear that we would want to do so anyway; while we could apply
5483          * labeling without the support of the TUN user the resulting labeled
5484          * traffic from the other end of the connection would almost certainly
5485          * cause confusion to the TUN user that had no idea network labeling
5486          * protocols were being used */
5487
5488         sksec->sid = tunsec->sid;
5489         sksec->sclass = SECCLASS_TUN_SOCKET;
5490
5491         return 0;
5492 }
5493
5494 static int selinux_tun_dev_open(void *security)
5495 {
5496         struct tun_security_struct *tunsec = security;
5497         u32 sid = current_sid();
5498         int err;
5499
5500         err = avc_has_perm(&selinux_state,
5501                            sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5502                            TUN_SOCKET__RELABELFROM, NULL);
5503         if (err)
5504                 return err;
5505         err = avc_has_perm(&selinux_state,
5506                            sid, sid, SECCLASS_TUN_SOCKET,
5507                            TUN_SOCKET__RELABELTO, NULL);
5508         if (err)
5509                 return err;
5510         tunsec->sid = sid;
5511
5512         return 0;
5513 }
5514
5515 #ifdef CONFIG_NETFILTER
5516
5517 static unsigned int selinux_ip_forward(struct sk_buff *skb,
5518                                        const struct net_device *indev,
5519                                        u16 family)
5520 {
5521         int err;
5522         char *addrp;
5523         u32 peer_sid;
5524         struct common_audit_data ad;
5525         struct lsm_network_audit net = {0,};
5526         u8 secmark_active;
5527         u8 netlbl_active;
5528         u8 peerlbl_active;
5529
5530         if (!selinux_policycap_netpeer())
5531                 return NF_ACCEPT;
5532
5533         secmark_active = selinux_secmark_enabled();
5534         netlbl_active = netlbl_enabled();
5535         peerlbl_active = selinux_peerlbl_enabled();
5536         if (!secmark_active && !peerlbl_active)
5537                 return NF_ACCEPT;
5538
5539         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5540                 return NF_DROP;
5541
5542         ad.type = LSM_AUDIT_DATA_NET;
5543         ad.u.net = &net;
5544         ad.u.net->netif = indev->ifindex;
5545         ad.u.net->family = family;
5546         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5547                 return NF_DROP;
5548
5549         if (peerlbl_active) {
5550                 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5551                                                addrp, family, peer_sid, &ad);
5552                 if (err) {
5553                         selinux_netlbl_err(skb, family, err, 1);
5554                         return NF_DROP;
5555                 }
5556         }
5557
5558         if (secmark_active)
5559                 if (avc_has_perm(&selinux_state,
5560                                  peer_sid, skb->secmark,
5561                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5562                         return NF_DROP;
5563
5564         if (netlbl_active)
5565                 /* we do this in the FORWARD path and not the POST_ROUTING
5566                  * path because we want to make sure we apply the necessary
5567                  * labeling before IPsec is applied so we can leverage AH
5568                  * protection */
5569                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5570                         return NF_DROP;
5571
5572         return NF_ACCEPT;
5573 }
5574
5575 static unsigned int selinux_ipv4_forward(void *priv,
5576                                          struct sk_buff *skb,
5577                                          const struct nf_hook_state *state)
5578 {
5579         return selinux_ip_forward(skb, state->in, PF_INET);
5580 }
5581
5582 #if IS_ENABLED(CONFIG_IPV6)
5583 static unsigned int selinux_ipv6_forward(void *priv,
5584                                          struct sk_buff *skb,
5585                                          const struct nf_hook_state *state)
5586 {
5587         return selinux_ip_forward(skb, state->in, PF_INET6);
5588 }
5589 #endif  /* IPV6 */
5590
5591 static unsigned int selinux_ip_output(struct sk_buff *skb,
5592                                       u16 family)
5593 {
5594         struct sock *sk;
5595         u32 sid;
5596
5597         if (!netlbl_enabled())
5598                 return NF_ACCEPT;
5599
5600         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5601          * because we want to make sure we apply the necessary labeling
5602          * before IPsec is applied so we can leverage AH protection */
5603         sk = skb->sk;
5604         if (sk) {
5605                 struct sk_security_struct *sksec;
5606
5607                 if (sk_listener(sk))
5608                         /* if the socket is the listening state then this
5609                          * packet is a SYN-ACK packet which means it needs to
5610                          * be labeled based on the connection/request_sock and
5611                          * not the parent socket.  unfortunately, we can't
5612                          * lookup the request_sock yet as it isn't queued on
5613                          * the parent socket until after the SYN-ACK is sent.
5614                          * the "solution" is to simply pass the packet as-is
5615                          * as any IP option based labeling should be copied
5616                          * from the initial connection request (in the IP
5617                          * layer).  it is far from ideal, but until we get a
5618                          * security label in the packet itself this is the
5619                          * best we can do. */
5620                         return NF_ACCEPT;
5621
5622                 /* standard practice, label using the parent socket */
5623                 sksec = sk->sk_security;
5624                 sid = sksec->sid;
5625         } else
5626                 sid = SECINITSID_KERNEL;
5627         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5628                 return NF_DROP;
5629
5630         return NF_ACCEPT;
5631 }
5632
5633 static unsigned int selinux_ipv4_output(void *priv,
5634                                         struct sk_buff *skb,
5635                                         const struct nf_hook_state *state)
5636 {
5637         return selinux_ip_output(skb, PF_INET);
5638 }
5639
5640 #if IS_ENABLED(CONFIG_IPV6)
5641 static unsigned int selinux_ipv6_output(void *priv,
5642                                         struct sk_buff *skb,
5643                                         const struct nf_hook_state *state)
5644 {
5645         return selinux_ip_output(skb, PF_INET6);
5646 }
5647 #endif  /* IPV6 */
5648
5649 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5650                                                 int ifindex,
5651                                                 u16 family)
5652 {
5653         struct sock *sk = skb_to_full_sk(skb);
5654         struct sk_security_struct *sksec;
5655         struct common_audit_data ad;
5656         struct lsm_network_audit net = {0,};
5657         char *addrp;
5658         u8 proto;
5659
5660         if (sk == NULL)
5661                 return NF_ACCEPT;
5662         sksec = sk->sk_security;
5663
5664         ad.type = LSM_AUDIT_DATA_NET;
5665         ad.u.net = &net;
5666         ad.u.net->netif = ifindex;
5667         ad.u.net->family = family;
5668         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5669                 return NF_DROP;
5670
5671         if (selinux_secmark_enabled())
5672                 if (avc_has_perm(&selinux_state,
5673                                  sksec->sid, skb->secmark,
5674                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5675                         return NF_DROP_ERR(-ECONNREFUSED);
5676
5677         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5678                 return NF_DROP_ERR(-ECONNREFUSED);
5679
5680         return NF_ACCEPT;
5681 }
5682
5683 static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5684                                          const struct net_device *outdev,
5685                                          u16 family)
5686 {
5687         u32 secmark_perm;
5688         u32 peer_sid;
5689         int ifindex = outdev->ifindex;
5690         struct sock *sk;
5691         struct common_audit_data ad;
5692         struct lsm_network_audit net = {0,};
5693         char *addrp;
5694         u8 secmark_active;
5695         u8 peerlbl_active;
5696
5697         /* If any sort of compatibility mode is enabled then handoff processing
5698          * to the selinux_ip_postroute_compat() function to deal with the
5699          * special handling.  We do this in an attempt to keep this function
5700          * as fast and as clean as possible. */
5701         if (!selinux_policycap_netpeer())
5702                 return selinux_ip_postroute_compat(skb, ifindex, family);
5703
5704         secmark_active = selinux_secmark_enabled();
5705         peerlbl_active = selinux_peerlbl_enabled();
5706         if (!secmark_active && !peerlbl_active)
5707                 return NF_ACCEPT;
5708
5709         sk = skb_to_full_sk(skb);
5710
5711 #ifdef CONFIG_XFRM
5712         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5713          * packet transformation so allow the packet to pass without any checks
5714          * since we'll have another chance to perform access control checks
5715          * when the packet is on it's final way out.
5716          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5717          *       is NULL, in this case go ahead and apply access control.
5718          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5719          *       TCP listening state we cannot wait until the XFRM processing
5720          *       is done as we will miss out on the SA label if we do;
5721          *       unfortunately, this means more work, but it is only once per
5722          *       connection. */
5723         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5724             !(sk && sk_listener(sk)))
5725                 return NF_ACCEPT;
5726 #endif
5727
5728         if (sk == NULL) {
5729                 /* Without an associated socket the packet is either coming
5730                  * from the kernel or it is being forwarded; check the packet
5731                  * to determine which and if the packet is being forwarded
5732                  * query the packet directly to determine the security label. */
5733                 if (skb->skb_iif) {
5734                         secmark_perm = PACKET__FORWARD_OUT;
5735                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5736                                 return NF_DROP;
5737                 } else {
5738                         secmark_perm = PACKET__SEND;
5739                         peer_sid = SECINITSID_KERNEL;
5740                 }
5741         } else if (sk_listener(sk)) {
5742                 /* Locally generated packet but the associated socket is in the
5743                  * listening state which means this is a SYN-ACK packet.  In
5744                  * this particular case the correct security label is assigned
5745                  * to the connection/request_sock but unfortunately we can't
5746                  * query the request_sock as it isn't queued on the parent
5747                  * socket until after the SYN-ACK packet is sent; the only
5748                  * viable choice is to regenerate the label like we do in
5749                  * selinux_inet_conn_request().  See also selinux_ip_output()
5750                  * for similar problems. */
5751                 u32 skb_sid;
5752                 struct sk_security_struct *sksec;
5753
5754                 sksec = sk->sk_security;
5755                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5756                         return NF_DROP;
5757                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5758                  * and the packet has been through at least one XFRM
5759                  * transformation then we must be dealing with the "final"
5760                  * form of labeled IPsec packet; since we've already applied
5761                  * all of our access controls on this packet we can safely
5762                  * pass the packet. */
5763                 if (skb_sid == SECSID_NULL) {
5764                         switch (family) {
5765                         case PF_INET:
5766                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5767                                         return NF_ACCEPT;
5768                                 break;
5769                         case PF_INET6:
5770                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5771                                         return NF_ACCEPT;
5772                                 break;
5773                         default:
5774                                 return NF_DROP_ERR(-ECONNREFUSED);
5775                         }
5776                 }
5777                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5778                         return NF_DROP;
5779                 secmark_perm = PACKET__SEND;
5780         } else {
5781                 /* Locally generated packet, fetch the security label from the
5782                  * associated socket. */
5783                 struct sk_security_struct *sksec = sk->sk_security;
5784                 peer_sid = sksec->sid;
5785                 secmark_perm = PACKET__SEND;
5786         }
5787
5788         ad.type = LSM_AUDIT_DATA_NET;
5789         ad.u.net = &net;
5790         ad.u.net->netif = ifindex;
5791         ad.u.net->family = family;
5792         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5793                 return NF_DROP;
5794
5795         if (secmark_active)
5796                 if (avc_has_perm(&selinux_state,
5797                                  peer_sid, skb->secmark,
5798                                  SECCLASS_PACKET, secmark_perm, &ad))
5799                         return NF_DROP_ERR(-ECONNREFUSED);
5800
5801         if (peerlbl_active) {
5802                 u32 if_sid;
5803                 u32 node_sid;
5804
5805                 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5806                         return NF_DROP;
5807                 if (avc_has_perm(&selinux_state,
5808                                  peer_sid, if_sid,
5809                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5810                         return NF_DROP_ERR(-ECONNREFUSED);
5811
5812                 if (sel_netnode_sid(addrp, family, &node_sid))
5813                         return NF_DROP;
5814                 if (avc_has_perm(&selinux_state,
5815                                  peer_sid, node_sid,
5816                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5817                         return NF_DROP_ERR(-ECONNREFUSED);
5818         }
5819
5820         return NF_ACCEPT;
5821 }
5822
5823 static unsigned int selinux_ipv4_postroute(void *priv,
5824                                            struct sk_buff *skb,
5825                                            const struct nf_hook_state *state)
5826 {
5827         return selinux_ip_postroute(skb, state->out, PF_INET);
5828 }
5829
5830 #if IS_ENABLED(CONFIG_IPV6)
5831 static unsigned int selinux_ipv6_postroute(void *priv,
5832                                            struct sk_buff *skb,
5833                                            const struct nf_hook_state *state)
5834 {
5835         return selinux_ip_postroute(skb, state->out, PF_INET6);
5836 }
5837 #endif  /* IPV6 */
5838
5839 #endif  /* CONFIG_NETFILTER */
5840
5841 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5842 {
5843         int rc = 0;
5844         unsigned int msg_len;
5845         unsigned int data_len = skb->len;
5846         unsigned char *data = skb->data;
5847         struct nlmsghdr *nlh;
5848         struct sk_security_struct *sksec = sk->sk_security;
5849         u16 sclass = sksec->sclass;
5850         u32 perm;
5851
5852         while (data_len >= nlmsg_total_size(0)) {
5853                 nlh = (struct nlmsghdr *)data;
5854
5855                 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5856                  *       users which means we can't reject skb's with bogus
5857                  *       length fields; our solution is to follow what
5858                  *       netlink_rcv_skb() does and simply skip processing at
5859                  *       messages with length fields that are clearly junk
5860                  */
5861                 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5862                         return 0;
5863
5864                 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5865                 if (rc == 0) {
5866                         rc = sock_has_perm(sk, perm);
5867                         if (rc)
5868                                 return rc;
5869                 } else if (rc == -EINVAL) {
5870                         /* -EINVAL is a missing msg/perm mapping */
5871                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5872                                 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5873                                 " pid=%d comm=%s\n",
5874                                 sk->sk_protocol, nlh->nlmsg_type,
5875                                 secclass_map[sclass - 1].name,
5876                                 task_pid_nr(current), current->comm);
5877                         if (enforcing_enabled(&selinux_state) &&
5878                             !security_get_allow_unknown(&selinux_state))
5879                                 return rc;
5880                         rc = 0;
5881                 } else if (rc == -ENOENT) {
5882                         /* -ENOENT is a missing socket/class mapping, ignore */
5883                         rc = 0;
5884                 } else {
5885                         return rc;
5886                 }
5887
5888                 /* move to the next message after applying netlink padding */
5889                 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5890                 if (msg_len >= data_len)
5891                         return 0;
5892                 data_len -= msg_len;
5893                 data += msg_len;
5894         }
5895
5896         return rc;
5897 }
5898
5899 static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5900 {
5901         isec->sclass = sclass;
5902         isec->sid = current_sid();
5903 }
5904
5905 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5906                         u32 perms)
5907 {
5908         struct ipc_security_struct *isec;
5909         struct common_audit_data ad;
5910         u32 sid = current_sid();
5911
5912         isec = selinux_ipc(ipc_perms);
5913
5914         ad.type = LSM_AUDIT_DATA_IPC;
5915         ad.u.ipc_id = ipc_perms->key;
5916
5917         return avc_has_perm(&selinux_state,
5918                             sid, isec->sid, isec->sclass, perms, &ad);
5919 }
5920
5921 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5922 {
5923         struct msg_security_struct *msec;
5924
5925         msec = selinux_msg_msg(msg);
5926         msec->sid = SECINITSID_UNLABELED;
5927
5928         return 0;
5929 }
5930
5931 /* message queue security operations */
5932 static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5933 {
5934         struct ipc_security_struct *isec;
5935         struct common_audit_data ad;
5936         u32 sid = current_sid();
5937         int rc;
5938
5939         isec = selinux_ipc(msq);
5940         ipc_init_security(isec, SECCLASS_MSGQ);
5941
5942         ad.type = LSM_AUDIT_DATA_IPC;
5943         ad.u.ipc_id = msq->key;
5944
5945         rc = avc_has_perm(&selinux_state,
5946                           sid, isec->sid, SECCLASS_MSGQ,
5947                           MSGQ__CREATE, &ad);
5948         return rc;
5949 }
5950
5951 static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
5952 {
5953         struct ipc_security_struct *isec;
5954         struct common_audit_data ad;
5955         u32 sid = current_sid();
5956
5957         isec = selinux_ipc(msq);
5958
5959         ad.type = LSM_AUDIT_DATA_IPC;
5960         ad.u.ipc_id = msq->key;
5961
5962         return avc_has_perm(&selinux_state,
5963                             sid, isec->sid, SECCLASS_MSGQ,
5964                             MSGQ__ASSOCIATE, &ad);
5965 }
5966
5967 static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
5968 {
5969         int err;
5970         int perms;
5971
5972         switch (cmd) {
5973         case IPC_INFO:
5974         case MSG_INFO:
5975                 /* No specific object, just general system-wide information. */
5976                 return avc_has_perm(&selinux_state,
5977                                     current_sid(), SECINITSID_KERNEL,
5978                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
5979         case IPC_STAT:
5980         case MSG_STAT:
5981         case MSG_STAT_ANY:
5982                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5983                 break;
5984         case IPC_SET:
5985                 perms = MSGQ__SETATTR;
5986                 break;
5987         case IPC_RMID:
5988                 perms = MSGQ__DESTROY;
5989                 break;
5990         default:
5991                 return 0;
5992         }
5993
5994         err = ipc_has_perm(msq, perms);
5995         return err;
5996 }
5997
5998 static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
5999 {
6000         struct ipc_security_struct *isec;
6001         struct msg_security_struct *msec;
6002         struct common_audit_data ad;
6003         u32 sid = current_sid();
6004         int rc;
6005
6006         isec = selinux_ipc(msq);
6007         msec = selinux_msg_msg(msg);
6008
6009         /*
6010          * First time through, need to assign label to the message
6011          */
6012         if (msec->sid == SECINITSID_UNLABELED) {
6013                 /*
6014                  * Compute new sid based on current process and
6015                  * message queue this message will be stored in
6016                  */
6017                 rc = security_transition_sid(&selinux_state, sid, isec->sid,
6018                                              SECCLASS_MSG, NULL, &msec->sid);
6019                 if (rc)
6020                         return rc;
6021         }
6022
6023         ad.type = LSM_AUDIT_DATA_IPC;
6024         ad.u.ipc_id = msq->key;
6025
6026         /* Can this process write to the queue? */
6027         rc = avc_has_perm(&selinux_state,
6028                           sid, isec->sid, SECCLASS_MSGQ,
6029                           MSGQ__WRITE, &ad);
6030         if (!rc)
6031                 /* Can this process send the message */
6032                 rc = avc_has_perm(&selinux_state,
6033                                   sid, msec->sid, SECCLASS_MSG,
6034                                   MSG__SEND, &ad);
6035         if (!rc)
6036                 /* Can the message be put in the queue? */
6037                 rc = avc_has_perm(&selinux_state,
6038                                   msec->sid, isec->sid, SECCLASS_MSGQ,
6039                                   MSGQ__ENQUEUE, &ad);
6040
6041         return rc;
6042 }
6043
6044 static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6045                                     struct task_struct *target,
6046                                     long type, int mode)
6047 {
6048         struct ipc_security_struct *isec;
6049         struct msg_security_struct *msec;
6050         struct common_audit_data ad;
6051         u32 sid = task_sid(target);
6052         int rc;
6053
6054         isec = selinux_ipc(msq);
6055         msec = selinux_msg_msg(msg);
6056
6057         ad.type = LSM_AUDIT_DATA_IPC;
6058         ad.u.ipc_id = msq->key;
6059
6060         rc = avc_has_perm(&selinux_state,
6061                           sid, isec->sid,
6062                           SECCLASS_MSGQ, MSGQ__READ, &ad);
6063         if (!rc)
6064                 rc = avc_has_perm(&selinux_state,
6065                                   sid, msec->sid,
6066                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
6067         return rc;
6068 }
6069
6070 /* Shared Memory security operations */
6071 static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6072 {
6073         struct ipc_security_struct *isec;
6074         struct common_audit_data ad;
6075         u32 sid = current_sid();
6076         int rc;
6077
6078         isec = selinux_ipc(shp);
6079         ipc_init_security(isec, SECCLASS_SHM);
6080
6081         ad.type = LSM_AUDIT_DATA_IPC;
6082         ad.u.ipc_id = shp->key;
6083
6084         rc = avc_has_perm(&selinux_state,
6085                           sid, isec->sid, SECCLASS_SHM,
6086                           SHM__CREATE, &ad);
6087         return rc;
6088 }
6089
6090 static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6091 {
6092         struct ipc_security_struct *isec;
6093         struct common_audit_data ad;
6094         u32 sid = current_sid();
6095
6096         isec = selinux_ipc(shp);
6097
6098         ad.type = LSM_AUDIT_DATA_IPC;
6099         ad.u.ipc_id = shp->key;
6100
6101         return avc_has_perm(&selinux_state,
6102                             sid, isec->sid, SECCLASS_SHM,
6103                             SHM__ASSOCIATE, &ad);
6104 }
6105
6106 /* Note, at this point, shp is locked down */
6107 static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6108 {
6109         int perms;
6110         int err;
6111
6112         switch (cmd) {
6113         case IPC_INFO:
6114         case SHM_INFO:
6115                 /* No specific object, just general system-wide information. */
6116                 return avc_has_perm(&selinux_state,
6117                                     current_sid(), SECINITSID_KERNEL,
6118                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6119         case IPC_STAT:
6120         case SHM_STAT:
6121         case SHM_STAT_ANY:
6122                 perms = SHM__GETATTR | SHM__ASSOCIATE;
6123                 break;
6124         case IPC_SET:
6125                 perms = SHM__SETATTR;
6126                 break;
6127         case SHM_LOCK:
6128         case SHM_UNLOCK:
6129                 perms = SHM__LOCK;
6130                 break;
6131         case IPC_RMID:
6132                 perms = SHM__DESTROY;
6133                 break;
6134         default:
6135                 return 0;
6136         }
6137
6138         err = ipc_has_perm(shp, perms);
6139         return err;
6140 }
6141
6142 static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6143                              char __user *shmaddr, int shmflg)
6144 {
6145         u32 perms;
6146
6147         if (shmflg & SHM_RDONLY)
6148                 perms = SHM__READ;
6149         else
6150                 perms = SHM__READ | SHM__WRITE;
6151
6152         return ipc_has_perm(shp, perms);
6153 }
6154
6155 /* Semaphore security operations */
6156 static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6157 {
6158         struct ipc_security_struct *isec;
6159         struct common_audit_data ad;
6160         u32 sid = current_sid();
6161         int rc;
6162
6163         isec = selinux_ipc(sma);
6164         ipc_init_security(isec, SECCLASS_SEM);
6165
6166         ad.type = LSM_AUDIT_DATA_IPC;
6167         ad.u.ipc_id = sma->key;
6168
6169         rc = avc_has_perm(&selinux_state,
6170                           sid, isec->sid, SECCLASS_SEM,
6171                           SEM__CREATE, &ad);
6172         return rc;
6173 }
6174
6175 static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6176 {
6177         struct ipc_security_struct *isec;
6178         struct common_audit_data ad;
6179         u32 sid = current_sid();
6180
6181         isec = selinux_ipc(sma);
6182
6183         ad.type = LSM_AUDIT_DATA_IPC;
6184         ad.u.ipc_id = sma->key;
6185
6186         return avc_has_perm(&selinux_state,
6187                             sid, isec->sid, SECCLASS_SEM,
6188                             SEM__ASSOCIATE, &ad);
6189 }
6190
6191 /* Note, at this point, sma is locked down */
6192 static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6193 {
6194         int err;
6195         u32 perms;
6196
6197         switch (cmd) {
6198         case IPC_INFO:
6199         case SEM_INFO:
6200                 /* No specific object, just general system-wide information. */
6201                 return avc_has_perm(&selinux_state,
6202                                     current_sid(), SECINITSID_KERNEL,
6203                                     SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6204         case GETPID:
6205         case GETNCNT:
6206         case GETZCNT:
6207                 perms = SEM__GETATTR;
6208                 break;
6209         case GETVAL:
6210         case GETALL:
6211                 perms = SEM__READ;
6212                 break;
6213         case SETVAL:
6214         case SETALL:
6215                 perms = SEM__WRITE;
6216                 break;
6217         case IPC_RMID:
6218                 perms = SEM__DESTROY;
6219                 break;
6220         case IPC_SET:
6221                 perms = SEM__SETATTR;
6222                 break;
6223         case IPC_STAT:
6224         case SEM_STAT:
6225         case SEM_STAT_ANY:
6226                 perms = SEM__GETATTR | SEM__ASSOCIATE;
6227                 break;
6228         default:
6229                 return 0;
6230         }
6231
6232         err = ipc_has_perm(sma, perms);
6233         return err;
6234 }
6235
6236 static int selinux_sem_semop(struct kern_ipc_perm *sma,
6237                              struct sembuf *sops, unsigned nsops, int alter)
6238 {
6239         u32 perms;
6240
6241         if (alter)
6242                 perms = SEM__READ | SEM__WRITE;
6243         else
6244                 perms = SEM__READ;
6245
6246         return ipc_has_perm(sma, perms);
6247 }
6248
6249 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6250 {
6251         u32 av = 0;
6252
6253         av = 0;
6254         if (flag & S_IRUGO)
6255                 av |= IPC__UNIX_READ;
6256         if (flag & S_IWUGO)
6257                 av |= IPC__UNIX_WRITE;
6258
6259         if (av == 0)
6260                 return 0;
6261
6262         return ipc_has_perm(ipcp, av);
6263 }
6264
6265 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6266 {
6267         struct ipc_security_struct *isec = selinux_ipc(ipcp);
6268         *secid = isec->sid;
6269 }
6270
6271 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6272 {
6273         if (inode)
6274                 inode_doinit_with_dentry(inode, dentry);
6275 }
6276
6277 static int selinux_getprocattr(struct task_struct *p,
6278                                char *name, char **value)
6279 {
6280         const struct task_security_struct *__tsec;
6281         u32 sid;
6282         int error;
6283         unsigned len;
6284
6285         rcu_read_lock();
6286         __tsec = selinux_cred(__task_cred(p));
6287
6288         if (current != p) {
6289                 error = avc_has_perm(&selinux_state,
6290                                      current_sid(), __tsec->sid,
6291                                      SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6292                 if (error)
6293                         goto bad;
6294         }
6295
6296         if (!strcmp(name, "current"))
6297                 sid = __tsec->sid;
6298         else if (!strcmp(name, "prev"))
6299                 sid = __tsec->osid;
6300         else if (!strcmp(name, "exec"))
6301                 sid = __tsec->exec_sid;
6302         else if (!strcmp(name, "fscreate"))
6303                 sid = __tsec->create_sid;
6304         else if (!strcmp(name, "keycreate"))
6305                 sid = __tsec->keycreate_sid;
6306         else if (!strcmp(name, "sockcreate"))
6307                 sid = __tsec->sockcreate_sid;
6308         else {
6309                 error = -EINVAL;
6310                 goto bad;
6311         }
6312         rcu_read_unlock();
6313
6314         if (!sid)
6315                 return 0;
6316
6317         error = security_sid_to_context(&selinux_state, sid, value, &len);
6318         if (error)
6319                 return error;
6320         return len;
6321
6322 bad:
6323         rcu_read_unlock();
6324         return error;
6325 }
6326
6327 static int selinux_setprocattr(const char *name, void *value, size_t size)
6328 {
6329         struct task_security_struct *tsec;
6330         struct cred *new;
6331         u32 mysid = current_sid(), sid = 0, ptsid;
6332         int error;
6333         char *str = value;
6334
6335         /*
6336          * Basic control over ability to set these attributes at all.
6337          */
6338         if (!strcmp(name, "exec"))
6339                 error = avc_has_perm(&selinux_state,
6340                                      mysid, mysid, SECCLASS_PROCESS,
6341                                      PROCESS__SETEXEC, NULL);
6342         else if (!strcmp(name, "fscreate"))
6343                 error = avc_has_perm(&selinux_state,
6344                                      mysid, mysid, SECCLASS_PROCESS,
6345                                      PROCESS__SETFSCREATE, NULL);
6346         else if (!strcmp(name, "keycreate"))
6347                 error = avc_has_perm(&selinux_state,
6348                                      mysid, mysid, SECCLASS_PROCESS,
6349                                      PROCESS__SETKEYCREATE, NULL);
6350         else if (!strcmp(name, "sockcreate"))
6351                 error = avc_has_perm(&selinux_state,
6352                                      mysid, mysid, SECCLASS_PROCESS,
6353                                      PROCESS__SETSOCKCREATE, NULL);
6354         else if (!strcmp(name, "current"))
6355                 error = avc_has_perm(&selinux_state,
6356                                      mysid, mysid, SECCLASS_PROCESS,
6357                                      PROCESS__SETCURRENT, NULL);
6358         else
6359                 error = -EINVAL;
6360         if (error)
6361                 return error;
6362
6363         /* Obtain a SID for the context, if one was specified. */
6364         if (size && str[0] && str[0] != '\n') {
6365                 if (str[size-1] == '\n') {
6366                         str[size-1] = 0;
6367                         size--;
6368                 }
6369                 error = security_context_to_sid(&selinux_state, value, size,
6370                                                 &sid, GFP_KERNEL);
6371                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
6372                         if (!has_cap_mac_admin(true)) {
6373                                 struct audit_buffer *ab;
6374                                 size_t audit_size;
6375
6376                                 /* We strip a nul only if it is at the end, otherwise the
6377                                  * context contains a nul and we should audit that */
6378                                 if (str[size - 1] == '\0')
6379                                         audit_size = size - 1;
6380                                 else
6381                                         audit_size = size;
6382                                 ab = audit_log_start(audit_context(),
6383                                                      GFP_ATOMIC,
6384                                                      AUDIT_SELINUX_ERR);
6385                                 audit_log_format(ab, "op=fscreate invalid_context=");
6386                                 audit_log_n_untrustedstring(ab, value, audit_size);
6387                                 audit_log_end(ab);
6388
6389                                 return error;
6390                         }
6391                         error = security_context_to_sid_force(
6392                                                       &selinux_state,
6393                                                       value, size, &sid);
6394                 }
6395                 if (error)
6396                         return error;
6397         }
6398
6399         new = prepare_creds();
6400         if (!new)
6401                 return -ENOMEM;
6402
6403         /* Permission checking based on the specified context is
6404            performed during the actual operation (execve,
6405            open/mkdir/...), when we know the full context of the
6406            operation.  See selinux_bprm_creds_for_exec for the execve
6407            checks and may_create for the file creation checks. The
6408            operation will then fail if the context is not permitted. */
6409         tsec = selinux_cred(new);
6410         if (!strcmp(name, "exec")) {
6411                 tsec->exec_sid = sid;
6412         } else if (!strcmp(name, "fscreate")) {
6413                 tsec->create_sid = sid;
6414         } else if (!strcmp(name, "keycreate")) {
6415                 if (sid) {
6416                         error = avc_has_perm(&selinux_state, mysid, sid,
6417                                              SECCLASS_KEY, KEY__CREATE, NULL);
6418                         if (error)
6419                                 goto abort_change;
6420                 }
6421                 tsec->keycreate_sid = sid;
6422         } else if (!strcmp(name, "sockcreate")) {
6423                 tsec->sockcreate_sid = sid;
6424         } else if (!strcmp(name, "current")) {
6425                 error = -EINVAL;
6426                 if (sid == 0)
6427                         goto abort_change;
6428
6429                 /* Only allow single threaded processes to change context */
6430                 error = -EPERM;
6431                 if (!current_is_single_threaded()) {
6432                         error = security_bounded_transition(&selinux_state,
6433                                                             tsec->sid, sid);
6434                         if (error)
6435                                 goto abort_change;
6436                 }
6437
6438                 /* Check permissions for the transition. */
6439                 error = avc_has_perm(&selinux_state,
6440                                      tsec->sid, sid, SECCLASS_PROCESS,
6441                                      PROCESS__DYNTRANSITION, NULL);
6442                 if (error)
6443                         goto abort_change;
6444
6445                 /* Check for ptracing, and update the task SID if ok.
6446                    Otherwise, leave SID unchanged and fail. */
6447                 ptsid = ptrace_parent_sid();
6448                 if (ptsid != 0) {
6449                         error = avc_has_perm(&selinux_state,
6450                                              ptsid, sid, SECCLASS_PROCESS,
6451                                              PROCESS__PTRACE, NULL);
6452                         if (error)
6453                                 goto abort_change;
6454                 }
6455
6456                 tsec->sid = sid;
6457         } else {
6458                 error = -EINVAL;
6459                 goto abort_change;
6460         }
6461
6462         commit_creds(new);
6463         return size;
6464
6465 abort_change:
6466         abort_creds(new);
6467         return error;
6468 }
6469
6470 static int selinux_ismaclabel(const char *name)
6471 {
6472         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6473 }
6474
6475 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6476 {
6477         return security_sid_to_context(&selinux_state, secid,
6478                                        secdata, seclen);
6479 }
6480
6481 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6482 {
6483         return security_context_to_sid(&selinux_state, secdata, seclen,
6484                                        secid, GFP_KERNEL);
6485 }
6486
6487 static void selinux_release_secctx(char *secdata, u32 seclen)
6488 {
6489         kfree(secdata);
6490 }
6491
6492 static void selinux_inode_invalidate_secctx(struct inode *inode)
6493 {
6494         struct inode_security_struct *isec = selinux_inode(inode);
6495
6496         spin_lock(&isec->lock);
6497         isec->initialized = LABEL_INVALID;
6498         spin_unlock(&isec->lock);
6499 }
6500
6501 /*
6502  *      called with inode->i_mutex locked
6503  */
6504 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6505 {
6506         int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6507                                            ctx, ctxlen, 0);
6508         /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6509         return rc == -EOPNOTSUPP ? 0 : rc;
6510 }
6511
6512 /*
6513  *      called with inode->i_mutex locked
6514  */
6515 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6516 {
6517         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6518 }
6519
6520 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6521 {
6522         int len = 0;
6523         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6524                                                 ctx, true);
6525         if (len < 0)
6526                 return len;
6527         *ctxlen = len;
6528         return 0;
6529 }
6530 #ifdef CONFIG_KEYS
6531
6532 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6533                              unsigned long flags)
6534 {
6535         const struct task_security_struct *tsec;
6536         struct key_security_struct *ksec;
6537
6538         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6539         if (!ksec)
6540                 return -ENOMEM;
6541
6542         tsec = selinux_cred(cred);
6543         if (tsec->keycreate_sid)
6544                 ksec->sid = tsec->keycreate_sid;
6545         else
6546                 ksec->sid = tsec->sid;
6547
6548         k->security = ksec;
6549         return 0;
6550 }
6551
6552 static void selinux_key_free(struct key *k)
6553 {
6554         struct key_security_struct *ksec = k->security;
6555
6556         k->security = NULL;
6557         kfree(ksec);
6558 }
6559
6560 static int selinux_key_permission(key_ref_t key_ref,
6561                                   const struct cred *cred,
6562                                   enum key_need_perm need_perm)
6563 {
6564         struct key *key;
6565         struct key_security_struct *ksec;
6566         u32 perm, sid;
6567
6568         switch (need_perm) {
6569         case KEY_NEED_VIEW:
6570                 perm = KEY__VIEW;
6571                 break;
6572         case KEY_NEED_READ:
6573                 perm = KEY__READ;
6574                 break;
6575         case KEY_NEED_WRITE:
6576                 perm = KEY__WRITE;
6577                 break;
6578         case KEY_NEED_SEARCH:
6579                 perm = KEY__SEARCH;
6580                 break;
6581         case KEY_NEED_LINK:
6582                 perm = KEY__LINK;
6583                 break;
6584         case KEY_NEED_SETATTR:
6585                 perm = KEY__SETATTR;
6586                 break;
6587         case KEY_NEED_UNLINK:
6588         case KEY_SYSADMIN_OVERRIDE:
6589         case KEY_AUTHTOKEN_OVERRIDE:
6590         case KEY_DEFER_PERM_CHECK:
6591                 return 0;
6592         default:
6593                 WARN_ON(1);
6594                 return -EPERM;
6595
6596         }
6597
6598         sid = cred_sid(cred);
6599         key = key_ref_to_ptr(key_ref);
6600         ksec = key->security;
6601
6602         return avc_has_perm(&selinux_state,
6603                             sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6604 }
6605
6606 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6607 {
6608         struct key_security_struct *ksec = key->security;
6609         char *context = NULL;
6610         unsigned len;
6611         int rc;
6612
6613         rc = security_sid_to_context(&selinux_state, ksec->sid,
6614                                      &context, &len);
6615         if (!rc)
6616                 rc = len;
6617         *_buffer = context;
6618         return rc;
6619 }
6620
6621 #ifdef CONFIG_KEY_NOTIFICATIONS
6622 static int selinux_watch_key(struct key *key)
6623 {
6624         struct key_security_struct *ksec = key->security;
6625         u32 sid = current_sid();
6626
6627         return avc_has_perm(&selinux_state,
6628                             sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6629 }
6630 #endif
6631 #endif
6632
6633 #ifdef CONFIG_SECURITY_INFINIBAND
6634 static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6635 {
6636         struct common_audit_data ad;
6637         int err;
6638         u32 sid = 0;
6639         struct ib_security_struct *sec = ib_sec;
6640         struct lsm_ibpkey_audit ibpkey;
6641
6642         err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6643         if (err)
6644                 return err;
6645
6646         ad.type = LSM_AUDIT_DATA_IBPKEY;
6647         ibpkey.subnet_prefix = subnet_prefix;
6648         ibpkey.pkey = pkey_val;
6649         ad.u.ibpkey = &ibpkey;
6650         return avc_has_perm(&selinux_state,
6651                             sec->sid, sid,
6652                             SECCLASS_INFINIBAND_PKEY,
6653                             INFINIBAND_PKEY__ACCESS, &ad);
6654 }
6655
6656 static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6657                                             u8 port_num)
6658 {
6659         struct common_audit_data ad;
6660         int err;
6661         u32 sid = 0;
6662         struct ib_security_struct *sec = ib_sec;
6663         struct lsm_ibendport_audit ibendport;
6664
6665         err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6666                                       &sid);
6667
6668         if (err)
6669                 return err;
6670
6671         ad.type = LSM_AUDIT_DATA_IBENDPORT;
6672         strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
6673         ibendport.port = port_num;
6674         ad.u.ibendport = &ibendport;
6675         return avc_has_perm(&selinux_state,
6676                             sec->sid, sid,
6677                             SECCLASS_INFINIBAND_ENDPORT,
6678                             INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6679 }
6680
6681 static int selinux_ib_alloc_security(void **ib_sec)
6682 {
6683         struct ib_security_struct *sec;
6684
6685         sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6686         if (!sec)
6687                 return -ENOMEM;
6688         sec->sid = current_sid();
6689
6690         *ib_sec = sec;
6691         return 0;
6692 }
6693
6694 static void selinux_ib_free_security(void *ib_sec)
6695 {
6696         kfree(ib_sec);
6697 }
6698 #endif
6699
6700 #ifdef CONFIG_BPF_SYSCALL
6701 static int selinux_bpf(int cmd, union bpf_attr *attr,
6702                                      unsigned int size)
6703 {
6704         u32 sid = current_sid();
6705         int ret;
6706
6707         switch (cmd) {
6708         case BPF_MAP_CREATE:
6709                 ret = avc_has_perm(&selinux_state,
6710                                    sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6711                                    NULL);
6712                 break;
6713         case BPF_PROG_LOAD:
6714                 ret = avc_has_perm(&selinux_state,
6715                                    sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6716                                    NULL);
6717                 break;
6718         default:
6719                 ret = 0;
6720                 break;
6721         }
6722
6723         return ret;
6724 }
6725
6726 static u32 bpf_map_fmode_to_av(fmode_t fmode)
6727 {
6728         u32 av = 0;
6729
6730         if (fmode & FMODE_READ)
6731                 av |= BPF__MAP_READ;
6732         if (fmode & FMODE_WRITE)
6733                 av |= BPF__MAP_WRITE;
6734         return av;
6735 }
6736
6737 /* This function will check the file pass through unix socket or binder to see
6738  * if it is a bpf related object. And apply correspinding checks on the bpf
6739  * object based on the type. The bpf maps and programs, not like other files and
6740  * socket, are using a shared anonymous inode inside the kernel as their inode.
6741  * So checking that inode cannot identify if the process have privilege to
6742  * access the bpf object and that's why we have to add this additional check in
6743  * selinux_file_receive and selinux_binder_transfer_files.
6744  */
6745 static int bpf_fd_pass(struct file *file, u32 sid)
6746 {
6747         struct bpf_security_struct *bpfsec;
6748         struct bpf_prog *prog;
6749         struct bpf_map *map;
6750         int ret;
6751
6752         if (file->f_op == &bpf_map_fops) {
6753                 map = file->private_data;
6754                 bpfsec = map->security;
6755                 ret = avc_has_perm(&selinux_state,
6756                                    sid, bpfsec->sid, SECCLASS_BPF,
6757                                    bpf_map_fmode_to_av(file->f_mode), NULL);
6758                 if (ret)
6759                         return ret;
6760         } else if (file->f_op == &bpf_prog_fops) {
6761                 prog = file->private_data;
6762                 bpfsec = prog->aux->security;
6763                 ret = avc_has_perm(&selinux_state,
6764                                    sid, bpfsec->sid, SECCLASS_BPF,
6765                                    BPF__PROG_RUN, NULL);
6766                 if (ret)
6767                         return ret;
6768         }
6769         return 0;
6770 }
6771
6772 static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6773 {
6774         u32 sid = current_sid();
6775         struct bpf_security_struct *bpfsec;
6776
6777         bpfsec = map->security;
6778         return avc_has_perm(&selinux_state,
6779                             sid, bpfsec->sid, SECCLASS_BPF,
6780                             bpf_map_fmode_to_av(fmode), NULL);
6781 }
6782
6783 static int selinux_bpf_prog(struct bpf_prog *prog)
6784 {
6785         u32 sid = current_sid();
6786         struct bpf_security_struct *bpfsec;
6787
6788         bpfsec = prog->aux->security;
6789         return avc_has_perm(&selinux_state,
6790                             sid, bpfsec->sid, SECCLASS_BPF,
6791                             BPF__PROG_RUN, NULL);
6792 }
6793
6794 static int selinux_bpf_map_alloc(struct bpf_map *map)
6795 {
6796         struct bpf_security_struct *bpfsec;
6797
6798         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6799         if (!bpfsec)
6800                 return -ENOMEM;
6801
6802         bpfsec->sid = current_sid();
6803         map->security = bpfsec;
6804
6805         return 0;
6806 }
6807
6808 static void selinux_bpf_map_free(struct bpf_map *map)
6809 {
6810         struct bpf_security_struct *bpfsec = map->security;
6811
6812         map->security = NULL;
6813         kfree(bpfsec);
6814 }
6815
6816 static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6817 {
6818         struct bpf_security_struct *bpfsec;
6819
6820         bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6821         if (!bpfsec)
6822                 return -ENOMEM;
6823
6824         bpfsec->sid = current_sid();
6825         aux->security = bpfsec;
6826
6827         return 0;
6828 }
6829
6830 static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6831 {
6832         struct bpf_security_struct *bpfsec = aux->security;
6833
6834         aux->security = NULL;
6835         kfree(bpfsec);
6836 }
6837 #endif
6838
6839 static int selinux_lockdown(enum lockdown_reason what)
6840 {
6841         struct common_audit_data ad;
6842         u32 sid = current_sid();
6843         int invalid_reason = (what <= LOCKDOWN_NONE) ||
6844                              (what == LOCKDOWN_INTEGRITY_MAX) ||
6845                              (what >= LOCKDOWN_CONFIDENTIALITY_MAX);
6846
6847         if (WARN(invalid_reason, "Invalid lockdown reason")) {
6848                 audit_log(audit_context(),
6849                           GFP_ATOMIC, AUDIT_SELINUX_ERR,
6850                           "lockdown_reason=invalid");
6851                 return -EINVAL;
6852         }
6853
6854         ad.type = LSM_AUDIT_DATA_LOCKDOWN;
6855         ad.u.reason = what;
6856
6857         if (what <= LOCKDOWN_INTEGRITY_MAX)
6858                 return avc_has_perm(&selinux_state,
6859                                     sid, sid, SECCLASS_LOCKDOWN,
6860                                     LOCKDOWN__INTEGRITY, &ad);
6861         else
6862                 return avc_has_perm(&selinux_state,
6863                                     sid, sid, SECCLASS_LOCKDOWN,
6864                                     LOCKDOWN__CONFIDENTIALITY, &ad);
6865 }
6866
6867 struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
6868         .lbs_cred = sizeof(struct task_security_struct),
6869         .lbs_file = sizeof(struct file_security_struct),
6870         .lbs_inode = sizeof(struct inode_security_struct),
6871         .lbs_ipc = sizeof(struct ipc_security_struct),
6872         .lbs_msg_msg = sizeof(struct msg_security_struct),
6873 };
6874
6875 #ifdef CONFIG_PERF_EVENTS
6876 static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
6877 {
6878         u32 requested, sid = current_sid();
6879
6880         if (type == PERF_SECURITY_OPEN)
6881                 requested = PERF_EVENT__OPEN;
6882         else if (type == PERF_SECURITY_CPU)
6883                 requested = PERF_EVENT__CPU;
6884         else if (type == PERF_SECURITY_KERNEL)
6885                 requested = PERF_EVENT__KERNEL;
6886         else if (type == PERF_SECURITY_TRACEPOINT)
6887                 requested = PERF_EVENT__TRACEPOINT;
6888         else
6889                 return -EINVAL;
6890
6891         return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT,
6892                             requested, NULL);
6893 }
6894
6895 static int selinux_perf_event_alloc(struct perf_event *event)
6896 {
6897         struct perf_event_security_struct *perfsec;
6898
6899         perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
6900         if (!perfsec)
6901                 return -ENOMEM;
6902
6903         perfsec->sid = current_sid();
6904         event->security = perfsec;
6905
6906         return 0;
6907 }
6908
6909 static void selinux_perf_event_free(struct perf_event *event)
6910 {
6911         struct perf_event_security_struct *perfsec = event->security;
6912
6913         event->security = NULL;
6914         kfree(perfsec);
6915 }
6916
6917 static int selinux_perf_event_read(struct perf_event *event)
6918 {
6919         struct perf_event_security_struct *perfsec = event->security;
6920         u32 sid = current_sid();
6921
6922         return avc_has_perm(&selinux_state, sid, perfsec->sid,
6923                             SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
6924 }
6925
6926 static int selinux_perf_event_write(struct perf_event *event)
6927 {
6928         struct perf_event_security_struct *perfsec = event->security;
6929         u32 sid = current_sid();
6930
6931         return avc_has_perm(&selinux_state, sid, perfsec->sid,
6932                             SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
6933 }
6934 #endif
6935
6936 /*
6937  * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
6938  * 1. any hooks that don't belong to (2.) or (3.) below,
6939  * 2. hooks that both access structures allocated by other hooks, and allocate
6940  *    structures that can be later accessed by other hooks (mostly "cloning"
6941  *    hooks),
6942  * 3. hooks that only allocate structures that can be later accessed by other
6943  *    hooks ("allocating" hooks).
6944  *
6945  * Please follow block comment delimiters in the list to keep this order.
6946  *
6947  * This ordering is needed for SELinux runtime disable to work at least somewhat
6948  * safely. Breaking the ordering rules above might lead to NULL pointer derefs
6949  * when disabling SELinux at runtime.
6950  */
6951 static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6952         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6953         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6954         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6955         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6956
6957         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6958         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6959         LSM_HOOK_INIT(capget, selinux_capget),
6960         LSM_HOOK_INIT(capset, selinux_capset),
6961         LSM_HOOK_INIT(capable, selinux_capable),
6962         LSM_HOOK_INIT(quotactl, selinux_quotactl),
6963         LSM_HOOK_INIT(quota_on, selinux_quota_on),
6964         LSM_HOOK_INIT(syslog, selinux_syslog),
6965         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6966
6967         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6968
6969         LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
6970         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6971         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6972
6973         LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6974         LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
6975         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6976         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6977         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6978         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6979         LSM_HOOK_INIT(sb_mount, selinux_mount),
6980         LSM_HOOK_INIT(sb_umount, selinux_umount),
6981         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6982         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6983
6984         LSM_HOOK_INIT(move_mount, selinux_move_mount),
6985
6986         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6987         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6988
6989         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6990         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6991         LSM_HOOK_INIT(inode_create, selinux_inode_create),
6992         LSM_HOOK_INIT(inode_link, selinux_inode_link),
6993         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6994         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6995         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6996         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6997         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6998         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6999         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
7000         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7001         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7002         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7003         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7004         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7005         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7006         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7007         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7008         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7009         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7010         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7011         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7012         LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7013         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7014         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7015         LSM_HOOK_INIT(path_notify, selinux_path_notify),
7016
7017         LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7018
7019         LSM_HOOK_INIT(file_permission, selinux_file_permission),
7020         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7021         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7022         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7023         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7024         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7025         LSM_HOOK_INIT(file_lock, selinux_file_lock),
7026         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7027         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7028         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7029         LSM_HOOK_INIT(file_receive, selinux_file_receive),
7030
7031         LSM_HOOK_INIT(file_open, selinux_file_open),
7032
7033         LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7034         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7035         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7036         LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7037         LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7038         LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7039         LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7040         LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7041         LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7042         LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7043         LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7044         LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7045         LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
7046         LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7047         LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7048         LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7049         LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7050         LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7051         LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7052         LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7053         LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7054         LSM_HOOK_INIT(task_kill, selinux_task_kill),
7055         LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7056
7057         LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7058         LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7059
7060         LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7061         LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7062         LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7063         LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7064
7065         LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7066         LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7067         LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7068
7069         LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7070         LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7071         LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7072
7073         LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7074
7075         LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7076         LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7077
7078         LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7079         LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7080         LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7081         LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7082         LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7083         LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7084
7085         LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7086         LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7087
7088         LSM_HOOK_INIT(socket_create, selinux_socket_create),
7089         LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7090         LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7091         LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7092         LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7093         LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7094         LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7095         LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7096         LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7097         LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7098         LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7099         LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7100         LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7101         LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7102         LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7103         LSM_HOOK_INIT(socket_getpeersec_stream,
7104                         selinux_socket_getpeersec_stream),
7105         LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7106         LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7107         LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7108         LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7109         LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7110         LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7111         LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7112         LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7113         LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7114         LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7115         LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7116         LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7117         LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7118         LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7119         LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7120         LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7121         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7122         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7123         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7124         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7125 #ifdef CONFIG_SECURITY_INFINIBAND
7126         LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7127         LSM_HOOK_INIT(ib_endport_manage_subnet,
7128                       selinux_ib_endport_manage_subnet),
7129         LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7130 #endif
7131 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7132         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7133         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7134         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7135         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7136         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7137         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7138                         selinux_xfrm_state_pol_flow_match),
7139         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7140 #endif
7141
7142 #ifdef CONFIG_KEYS
7143         LSM_HOOK_INIT(key_free, selinux_key_free),
7144         LSM_HOOK_INIT(key_permission, selinux_key_permission),
7145         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7146 #ifdef CONFIG_KEY_NOTIFICATIONS
7147         LSM_HOOK_INIT(watch_key, selinux_watch_key),
7148 #endif
7149 #endif
7150
7151 #ifdef CONFIG_AUDIT
7152         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7153         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7154         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7155 #endif
7156
7157 #ifdef CONFIG_BPF_SYSCALL
7158         LSM_HOOK_INIT(bpf, selinux_bpf),
7159         LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7160         LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7161         LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7162         LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7163 #endif
7164
7165 #ifdef CONFIG_PERF_EVENTS
7166         LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7167         LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7168         LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7169         LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7170 #endif
7171
7172         LSM_HOOK_INIT(locked_down, selinux_lockdown),
7173
7174         /*
7175          * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7176          */
7177         LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7178         LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7179         LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7180         LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt),
7181 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7182         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7183 #endif
7184
7185         /*
7186          * PUT "ALLOCATING" HOOKS HERE
7187          */
7188         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7189         LSM_HOOK_INIT(msg_queue_alloc_security,
7190                       selinux_msg_queue_alloc_security),
7191         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7192         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7193         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7194         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7195         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7196         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7197         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7198         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7199 #ifdef CONFIG_SECURITY_INFINIBAND
7200         LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7201 #endif
7202 #ifdef CONFIG_SECURITY_NETWORK_XFRM
7203         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7204         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7205         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7206                       selinux_xfrm_state_alloc_acquire),
7207 #endif
7208 #ifdef CONFIG_KEYS
7209         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7210 #endif
7211 #ifdef CONFIG_AUDIT
7212         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7213 #endif
7214 #ifdef CONFIG_BPF_SYSCALL
7215         LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7216         LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7217 #endif
7218 #ifdef CONFIG_PERF_EVENTS
7219         LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7220 #endif
7221 };
7222
7223 static __init int selinux_init(void)
7224 {
7225         pr_info("SELinux:  Initializing.\n");
7226
7227         memset(&selinux_state, 0, sizeof(selinux_state));
7228         enforcing_set(&selinux_state, selinux_enforcing_boot);
7229         selinux_state.checkreqprot = selinux_checkreqprot_boot;
7230         selinux_ss_init(&selinux_state.ss);
7231         selinux_avc_init(&selinux_state.avc);
7232         mutex_init(&selinux_state.status_lock);
7233
7234         /* Set the security state for the initial task. */
7235         cred_init_security();
7236
7237         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7238
7239         avc_init();
7240
7241         avtab_cache_init();
7242
7243         ebitmap_cache_init();
7244
7245         hashtab_cache_init();
7246
7247         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7248
7249         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7250                 panic("SELinux: Unable to register AVC netcache callback\n");
7251
7252         if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7253                 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7254
7255         if (selinux_enforcing_boot)
7256                 pr_debug("SELinux:  Starting in enforcing mode\n");
7257         else
7258                 pr_debug("SELinux:  Starting in permissive mode\n");
7259
7260         fs_validate_description("selinux", selinux_fs_parameters);
7261
7262         return 0;
7263 }
7264
7265 static void delayed_superblock_init(struct super_block *sb, void *unused)
7266 {
7267         selinux_set_mnt_opts(sb, NULL, 0, NULL);
7268 }
7269
7270 void selinux_complete_init(void)
7271 {
7272         pr_debug("SELinux:  Completing initialization.\n");
7273
7274         /* Set up any superblocks initialized prior to the policy load. */
7275         pr_debug("SELinux:  Setting up existing superblocks.\n");
7276         iterate_supers(delayed_superblock_init, NULL);
7277 }
7278
7279 /* SELinux requires early initialization in order to label
7280    all processes and objects when they are created. */
7281 DEFINE_LSM(selinux) = {
7282         .name = "selinux",
7283         .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7284         .enabled = &selinux_enabled_boot,
7285         .blobs = &selinux_blob_sizes,
7286         .init = selinux_init,
7287 };
7288
7289 #if defined(CONFIG_NETFILTER)
7290
7291 static const struct nf_hook_ops selinux_nf_ops[] = {
7292         {
7293                 .hook =         selinux_ipv4_postroute,
7294                 .pf =           NFPROTO_IPV4,
7295                 .hooknum =      NF_INET_POST_ROUTING,
7296                 .priority =     NF_IP_PRI_SELINUX_LAST,
7297         },
7298         {
7299                 .hook =         selinux_ipv4_forward,
7300                 .pf =           NFPROTO_IPV4,
7301                 .hooknum =      NF_INET_FORWARD,
7302                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7303         },
7304         {
7305                 .hook =         selinux_ipv4_output,
7306                 .pf =           NFPROTO_IPV4,
7307                 .hooknum =      NF_INET_LOCAL_OUT,
7308                 .priority =     NF_IP_PRI_SELINUX_FIRST,
7309         },
7310 #if IS_ENABLED(CONFIG_IPV6)
7311         {
7312                 .hook =         selinux_ipv6_postroute,
7313                 .pf =           NFPROTO_IPV6,
7314                 .hooknum =      NF_INET_POST_ROUTING,
7315                 .priority =     NF_IP6_PRI_SELINUX_LAST,
7316         },
7317         {
7318                 .hook =         selinux_ipv6_forward,
7319                 .pf =           NFPROTO_IPV6,
7320                 .hooknum =      NF_INET_FORWARD,
7321                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7322         },
7323         {
7324                 .hook =         selinux_ipv6_output,
7325                 .pf =           NFPROTO_IPV6,
7326                 .hooknum =      NF_INET_LOCAL_OUT,
7327                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
7328         },
7329 #endif  /* IPV6 */
7330 };
7331
7332 static int __net_init selinux_nf_register(struct net *net)
7333 {
7334         return nf_register_net_hooks(net, selinux_nf_ops,
7335                                      ARRAY_SIZE(selinux_nf_ops));
7336 }
7337
7338 static void __net_exit selinux_nf_unregister(struct net *net)
7339 {
7340         nf_unregister_net_hooks(net, selinux_nf_ops,
7341                                 ARRAY_SIZE(selinux_nf_ops));
7342 }
7343
7344 static struct pernet_operations selinux_net_ops = {
7345         .init = selinux_nf_register,
7346         .exit = selinux_nf_unregister,
7347 };
7348
7349 static int __init selinux_nf_ip_init(void)
7350 {
7351         int err;
7352
7353         if (!selinux_enabled_boot)
7354                 return 0;
7355
7356         pr_debug("SELinux:  Registering netfilter hooks\n");
7357
7358         err = register_pernet_subsys(&selinux_net_ops);
7359         if (err)
7360                 panic("SELinux: register_pernet_subsys: error %d\n", err);
7361
7362         return 0;
7363 }
7364 __initcall(selinux_nf_ip_init);
7365
7366 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7367 static void selinux_nf_ip_exit(void)
7368 {
7369         pr_debug("SELinux:  Unregistering netfilter hooks\n");
7370
7371         unregister_pernet_subsys(&selinux_net_ops);
7372 }
7373 #endif
7374
7375 #else /* CONFIG_NETFILTER */
7376
7377 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7378 #define selinux_nf_ip_exit()
7379 #endif
7380
7381 #endif /* CONFIG_NETFILTER */
7382
7383 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
7384 int selinux_disable(struct selinux_state *state)
7385 {
7386         if (selinux_initialized(state)) {
7387                 /* Not permitted after initial policy load. */
7388                 return -EINVAL;
7389         }
7390
7391         if (selinux_disabled(state)) {
7392                 /* Only do this once. */
7393                 return -EINVAL;
7394         }
7395
7396         selinux_mark_disabled(state);
7397
7398         pr_info("SELinux:  Disabled at runtime.\n");
7399
7400         /*
7401          * Unregister netfilter hooks.
7402          * Must be done before security_delete_hooks() to avoid breaking
7403          * runtime disable.
7404          */
7405         selinux_nf_ip_exit();
7406
7407         security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7408
7409         /* Try to destroy the avc node cache */
7410         avc_disable();
7411
7412         /* Unregister selinuxfs. */
7413         exit_sel_fs();
7414
7415         return 0;
7416 }
7417 #endif