security/selinux/selinuxfs.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* Updated: Karl MacMillan <kmacmillan@tresys.com>
   3  *
   4  *      Added conditional policy language extensions
   5  *
   6  *  Updated: Hewlett-Packard <paul@paul-moore.com>
   7  *
   8  *      Added support for the policy capability bitmap
   9  *
  10  * Copyright (C) 2007 Hewlett-Packard Development Company, L.P.
  11  * Copyright (C) 2003 - 2004 Tresys Technology, LLC
  12  * Copyright (C) 2004 Red Hat, Inc., James Morris <jmorris@redhat.com>
  13  */
  14
  15 #include <linux/kernel.h>
  16 #include <linux/pagemap.h>
  17 #include <linux/slab.h>
  18 #include <linux/vmalloc.h>
  19 #include <linux/fs.h>
  20 #include <linux/fs_context.h>
  21 #include <linux/mount.h>
  22 #include <linux/mutex.h>
  23 #include <linux/namei.h>
  24 #include <linux/init.h>
  25 #include <linux/string.h>
  26 #include <linux/security.h>
  27 #include <linux/major.h>
  28 #include <linux/seq_file.h>
  29 #include <linux/percpu.h>
  30 #include <linux/audit.h>
  31 #include <linux/uaccess.h>
  32 #include <linux/kobject.h>
  33 #include <linux/ctype.h>
  34
  35 /* selinuxfs pseudo filesystem for exporting the security policy API.
  36    Based on the proc code and the fs/nfsd/nfsctl.c code. */
  37
  38 #include "flask.h"
  39 #include "avc.h"
  40 #include "avc_ss.h"
  41 #include "security.h"
  42 #include "objsec.h"
  43 #include "conditional.h"
  44
  45 enum sel_inos {
  46         SEL_ROOT_INO = 2,
  47         SEL_LOAD,       /* load policy */
  48         SEL_ENFORCE,    /* get or set enforcing status */
  49         SEL_CONTEXT,    /* validate context */
  50         SEL_ACCESS,     /* compute access decision */
  51         SEL_CREATE,     /* compute create labeling decision */
  52         SEL_RELABEL,    /* compute relabeling decision */
  53         SEL_USER,       /* compute reachable user contexts */
  54         SEL_POLICYVERS, /* return policy version for this kernel */
  55         SEL_COMMIT_BOOLS, /* commit new boolean values */
  56         SEL_MLS,        /* return if MLS policy is enabled */
  57         SEL_DISABLE,    /* disable SELinux until next reboot */
  58         SEL_MEMBER,     /* compute polyinstantiation membership decision */
  59         SEL_CHECKREQPROT, /* check requested protection, not kernel-applied one */
  60         SEL_COMPAT_NET, /* whether to use old compat network packet controls */
  61         SEL_REJECT_UNKNOWN, /* export unknown reject handling to userspace */
  62         SEL_DENY_UNKNOWN, /* export unknown deny handling to userspace */
  63         SEL_STATUS,     /* export current status using mmap() */
  64         SEL_POLICY,     /* allow userspace to read the in kernel policy */
  65         SEL_VALIDATE_TRANS, /* compute validatetrans decision */
  66         SEL_INO_NEXT,   /* The next inode number to use */
  67 };
  68
  69 struct selinux_fs_info {
  70         struct dentry *bool_dir;
  71         unsigned int bool_num;
  72         char **bool_pending_names;
  73         unsigned int *bool_pending_values;
  74         struct dentry *class_dir;
  75         unsigned long last_class_ino;
  76         bool policy_opened;
  77         struct dentry *policycap_dir;
  78         unsigned long last_ino;
  79         struct selinux_state *state;
  80         struct super_block *sb;
  81 };
  82
  83 static int selinux_fs_info_create(struct super_block *sb)
  84 {
  85         struct selinux_fs_info *fsi;
  86
  87         fsi = kzalloc(sizeof(*fsi), GFP_KERNEL);
  88         if (!fsi)
  89                 return -ENOMEM;
  90
  91         fsi->last_ino = SEL_INO_NEXT - 1;
  92         fsi->state = &selinux_state;
  93         fsi->sb = sb;
  94         sb->s_fs_info = fsi;
  95         return 0;
  96 }
  97
  98 static void selinux_fs_info_free(struct super_block *sb)
  99 {
 100         struct selinux_fs_info *fsi = sb->s_fs_info;
 101         int i;
 102
 103         if (fsi) {
 104                 for (i = 0; i < fsi->bool_num; i++)
 105                         kfree(fsi->bool_pending_names[i]);
 106                 kfree(fsi->bool_pending_names);
 107                 kfree(fsi->bool_pending_values);
 108         }
 109         kfree(sb->s_fs_info);
 110         sb->s_fs_info = NULL;
 111 }
 112
 113 #define SEL_INITCON_INO_OFFSET          0x01000000
 114 #define SEL_BOOL_INO_OFFSET             0x02000000
 115 #define SEL_CLASS_INO_OFFSET            0x04000000
 116 #define SEL_POLICYCAP_INO_OFFSET        0x08000000
 117 #define SEL_INO_MASK                    0x00ffffff
 118
 119 #define BOOL_DIR_NAME "booleans"
 120 #define CLASS_DIR_NAME "class"
 121 #define POLICYCAP_DIR_NAME "policy_capabilities"
 122
 123 #define TMPBUFLEN       12
 124 static ssize_t sel_read_enforce(struct file *filp, char __user *buf,
 125                                 size_t count, loff_t *ppos)
 126 {
 127         struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 128         char tmpbuf[TMPBUFLEN];
 129         ssize_t length;
 130
 131         length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 132                            enforcing_enabled(fsi->state));
 133         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 134 }
 135
 136 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 137 static ssize_t sel_write_enforce(struct file *file, const char __user *buf,
 138                                  size_t count, loff_t *ppos)
 139
 140 {
 141         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 142         struct selinux_state *state = fsi->state;
 143         char *page = NULL;
 144         ssize_t length;
 145         int old_value, new_value;
 146
 147         if (count >= PAGE_SIZE)
 148                 return -ENOMEM;
 149
 150         /* No partial writes. */
 151         if (*ppos != 0)
 152                 return -EINVAL;
 153
 154         page = memdup_user_nul(buf, count);
 155         if (IS_ERR(page))
 156                 return PTR_ERR(page);
 157
 158         length = -EINVAL;
 159         if (sscanf(page, "%d", &new_value) != 1)
 160                 goto out;
 161
 162         new_value = !!new_value;
 163
 164         old_value = enforcing_enabled(state);
 165         if (new_value != old_value) {
 166                 length = avc_has_perm(&selinux_state,
 167                                       current_sid(), SECINITSID_SECURITY,
 168                                       SECCLASS_SECURITY, SECURITY__SETENFORCE,
 169                                       NULL);
 170                 if (length)
 171                         goto out;
 172                 audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
 173                         "enforcing=%d old_enforcing=%d auid=%u ses=%u"
 174                         " enabled=1 old-enabled=1 lsm=selinux res=1",
 175                         new_value, old_value,
 176                         from_kuid(&init_user_ns, audit_get_loginuid(current)),
 177                         audit_get_sessionid(current));
 178                 enforcing_set(state, new_value);
 179                 if (new_value)
 180                         avc_ss_reset(state->avc, 0);
 181                 selnl_notify_setenforce(new_value);
 182                 selinux_status_update_setenforce(state, new_value);
 183                 if (!new_value)
 184                         call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
 185         }
 186         length = count;
 187 out:
 188         kfree(page);
 189         return length;
 190 }
 191 #else
 192 #define sel_write_enforce NULL
 193 #endif
 194
 195 static const struct file_operations sel_enforce_ops = {
 196         .read           = sel_read_enforce,
 197         .write          = sel_write_enforce,
 198         .llseek         = generic_file_llseek,
 199 };
 200
 201 static ssize_t sel_read_handle_unknown(struct file *filp, char __user *buf,
 202                                         size_t count, loff_t *ppos)
 203 {
 204         struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 205         struct selinux_state *state = fsi->state;
 206         char tmpbuf[TMPBUFLEN];
 207         ssize_t length;
 208         ino_t ino = file_inode(filp)->i_ino;
 209         int handle_unknown = (ino == SEL_REJECT_UNKNOWN) ?
 210                 security_get_reject_unknown(state) :
 211                 !security_get_allow_unknown(state);
 212
 213         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", handle_unknown);
 214         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 215 }
 216
 217 static const struct file_operations sel_handle_unknown_ops = {
 218         .read           = sel_read_handle_unknown,
 219         .llseek         = generic_file_llseek,
 220 };
 221
 222 static int sel_open_handle_status(struct inode *inode, struct file *filp)
 223 {
 224         struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 225         struct page    *status = selinux_kernel_status_page(fsi->state);
 226
 227         if (!status)
 228                 return -ENOMEM;
 229
 230         filp->private_data = status;
 231
 232         return 0;
 233 }
 234
 235 static ssize_t sel_read_handle_status(struct file *filp, char __user *buf,
 236                                       size_t count, loff_t *ppos)
 237 {
 238         struct page    *status = filp->private_data;
 239
 240         BUG_ON(!status);
 241
 242         return simple_read_from_buffer(buf, count, ppos,
 243                                        page_address(status),
 244                                        sizeof(struct selinux_kernel_status));
 245 }
 246
 247 static int sel_mmap_handle_status(struct file *filp,
 248                                   struct vm_area_struct *vma)
 249 {
 250         struct page    *status = filp->private_data;
 251         unsigned long   size = vma->vm_end - vma->vm_start;
 252
 253         BUG_ON(!status);
 254
 255         /* only allows one page from the head */
 256         if (vma->vm_pgoff > 0 || size != PAGE_SIZE)
 257                 return -EIO;
 258         /* disallow writable mapping */
 259         if (vma->vm_flags & VM_WRITE)
 260                 return -EPERM;
 261         /* disallow mprotect() turns it into writable */
 262         vma->vm_flags &= ~VM_MAYWRITE;
 263
 264         return remap_pfn_range(vma, vma->vm_start,
 265                                page_to_pfn(status),
 266                                size, vma->vm_page_prot);
 267 }
 268
 269 static const struct file_operations sel_handle_status_ops = {
 270         .open           = sel_open_handle_status,
 271         .read           = sel_read_handle_status,
 272         .mmap           = sel_mmap_handle_status,
 273         .llseek         = generic_file_llseek,
 274 };
 275
 276 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
 277 static ssize_t sel_write_disable(struct file *file, const char __user *buf,
 278                                  size_t count, loff_t *ppos)
 279
 280 {
 281         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 282         char *page;
 283         ssize_t length;
 284         int new_value;
 285         int enforcing;
 286
 287         /* NOTE: we are now officially considering runtime disable as
 288          *       deprecated, and using it will become increasingly painful
 289          *       (e.g. sleeping/blocking) as we progress through future
 290          *       kernel releases until eventually it is removed
 291          */
 292         pr_err("SELinux:  Runtime disable is deprecated, use selinux=0 on the kernel cmdline.\n");
 293
 294         if (count >= PAGE_SIZE)
 295                 return -ENOMEM;
 296
 297         /* No partial writes. */
 298         if (*ppos != 0)
 299                 return -EINVAL;
 300
 301         page = memdup_user_nul(buf, count);
 302         if (IS_ERR(page))
 303                 return PTR_ERR(page);
 304
 305         length = -EINVAL;
 306         if (sscanf(page, "%d", &new_value) != 1)
 307                 goto out;
 308
 309         if (new_value) {
 310                 enforcing = enforcing_enabled(fsi->state);
 311                 length = selinux_disable(fsi->state);
 312                 if (length)
 313                         goto out;
 314                 audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_STATUS,
 315                         "enforcing=%d old_enforcing=%d auid=%u ses=%u"
 316                         " enabled=0 old-enabled=1 lsm=selinux res=1",
 317                         enforcing, enforcing,
 318                         from_kuid(&init_user_ns, audit_get_loginuid(current)),
 319                         audit_get_sessionid(current));
 320         }
 321
 322         length = count;
 323 out:
 324         kfree(page);
 325         return length;
 326 }
 327 #else
 328 #define sel_write_disable NULL
 329 #endif
 330
 331 static const struct file_operations sel_disable_ops = {
 332         .write          = sel_write_disable,
 333         .llseek         = generic_file_llseek,
 334 };
 335
 336 static ssize_t sel_read_policyvers(struct file *filp, char __user *buf,
 337                                    size_t count, loff_t *ppos)
 338 {
 339         char tmpbuf[TMPBUFLEN];
 340         ssize_t length;
 341
 342         length = scnprintf(tmpbuf, TMPBUFLEN, "%u", POLICYDB_VERSION_MAX);
 343         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 344 }
 345
 346 static const struct file_operations sel_policyvers_ops = {
 347         .read           = sel_read_policyvers,
 348         .llseek         = generic_file_llseek,
 349 };
 350
 351 /* declaration for sel_write_load */
 352 static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
 353                           unsigned int *bool_num, char ***bool_pending_names,
 354                           unsigned int **bool_pending_values);
 355 static int sel_make_classes(struct selinux_policy *newpolicy,
 356                             struct dentry *class_dir,
 357                             unsigned long *last_class_ino);
 358
 359 /* declaration for sel_make_class_dirs */
 360 static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
 361                         unsigned long *ino);
 362
 363 /* declaration for sel_make_policy_nodes */
 364 static struct dentry *sel_make_disconnected_dir(struct super_block *sb,
 365                                                 unsigned long *ino);
 366
 367 /* declaration for sel_make_policy_nodes */
 368 static void sel_remove_entries(struct dentry *de);
 369
 370 static ssize_t sel_read_mls(struct file *filp, char __user *buf,
 371                                 size_t count, loff_t *ppos)
 372 {
 373         struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 374         char tmpbuf[TMPBUFLEN];
 375         ssize_t length;
 376
 377         length = scnprintf(tmpbuf, TMPBUFLEN, "%d",
 378                            security_mls_enabled(fsi->state));
 379         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 380 }
 381
 382 static const struct file_operations sel_mls_ops = {
 383         .read           = sel_read_mls,
 384         .llseek         = generic_file_llseek,
 385 };
 386
 387 struct policy_load_memory {
 388         size_t len;
 389         void *data;
 390 };
 391
 392 static int sel_open_policy(struct inode *inode, struct file *filp)
 393 {
 394         struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
 395         struct selinux_state *state = fsi->state;
 396         struct policy_load_memory *plm = NULL;
 397         int rc;
 398
 399         BUG_ON(filp->private_data);
 400
 401         mutex_lock(&fsi->state->policy_mutex);
 402
 403         rc = avc_has_perm(&selinux_state,
 404                           current_sid(), SECINITSID_SECURITY,
 405                           SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
 406         if (rc)
 407                 goto err;
 408
 409         rc = -EBUSY;
 410         if (fsi->policy_opened)
 411                 goto err;
 412
 413         rc = -ENOMEM;
 414         plm = kzalloc(sizeof(*plm), GFP_KERNEL);
 415         if (!plm)
 416                 goto err;
 417
 418         rc = security_read_policy(state, &plm->data, &plm->len);
 419         if (rc)
 420                 goto err;
 421
 422         if ((size_t)i_size_read(inode) != plm->len) {
 423                 inode_lock(inode);
 424                 i_size_write(inode, plm->len);
 425                 inode_unlock(inode);
 426         }
 427
 428         fsi->policy_opened = 1;
 429
 430         filp->private_data = plm;
 431
 432         mutex_unlock(&fsi->state->policy_mutex);
 433
 434         return 0;
 435 err:
 436         mutex_unlock(&fsi->state->policy_mutex);
 437
 438         if (plm)
 439                 vfree(plm->data);
 440         kfree(plm);
 441         return rc;
 442 }
 443
 444 static int sel_release_policy(struct inode *inode, struct file *filp)
 445 {
 446         struct selinux_fs_info *fsi = inode->i_sb->s_fs_info;
 447         struct policy_load_memory *plm = filp->private_data;
 448
 449         BUG_ON(!plm);
 450
 451         fsi->policy_opened = 0;
 452
 453         vfree(plm->data);
 454         kfree(plm);
 455
 456         return 0;
 457 }
 458
 459 static ssize_t sel_read_policy(struct file *filp, char __user *buf,
 460                                size_t count, loff_t *ppos)
 461 {
 462         struct policy_load_memory *plm = filp->private_data;
 463         int ret;
 464
 465         ret = avc_has_perm(&selinux_state,
 466                            current_sid(), SECINITSID_SECURITY,
 467                           SECCLASS_SECURITY, SECURITY__READ_POLICY, NULL);
 468         if (ret)
 469                 return ret;
 470
 471         return simple_read_from_buffer(buf, count, ppos, plm->data, plm->len);
 472 }
 473
 474 static vm_fault_t sel_mmap_policy_fault(struct vm_fault *vmf)
 475 {
 476         struct policy_load_memory *plm = vmf->vma->vm_file->private_data;
 477         unsigned long offset;
 478         struct page *page;
 479
 480         if (vmf->flags & (FAULT_FLAG_MKWRITE | FAULT_FLAG_WRITE))
 481                 return VM_FAULT_SIGBUS;
 482
 483         offset = vmf->pgoff << PAGE_SHIFT;
 484         if (offset >= roundup(plm->len, PAGE_SIZE))
 485                 return VM_FAULT_SIGBUS;
 486
 487         page = vmalloc_to_page(plm->data + offset);
 488         get_page(page);
 489
 490         vmf->page = page;
 491
 492         return 0;
 493 }
 494
 495 static const struct vm_operations_struct sel_mmap_policy_ops = {
 496         .fault = sel_mmap_policy_fault,
 497         .page_mkwrite = sel_mmap_policy_fault,
 498 };
 499
 500 static int sel_mmap_policy(struct file *filp, struct vm_area_struct *vma)
 501 {
 502         if (vma->vm_flags & VM_SHARED) {
 503                 /* do not allow mprotect to make mapping writable */
 504                 vma->vm_flags &= ~VM_MAYWRITE;
 505
 506                 if (vma->vm_flags & VM_WRITE)
 507                         return -EACCES;
 508         }
 509
 510         vma->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP;
 511         vma->vm_ops = &sel_mmap_policy_ops;
 512
 513         return 0;
 514 }
 515
 516 static const struct file_operations sel_policy_ops = {
 517         .open           = sel_open_policy,
 518         .read           = sel_read_policy,
 519         .mmap           = sel_mmap_policy,
 520         .release        = sel_release_policy,
 521         .llseek         = generic_file_llseek,
 522 };
 523
 524 static void sel_remove_old_bool_data(unsigned int bool_num, char **bool_names,
 525                                 unsigned int *bool_values)
 526 {
 527         u32 i;
 528
 529         /* bool_dir cleanup */
 530         for (i = 0; i < bool_num; i++)
 531                 kfree(bool_names[i]);
 532         kfree(bool_names);
 533         kfree(bool_values);
 534 }
 535
 536 static int sel_make_policy_nodes(struct selinux_fs_info *fsi,
 537                                 struct selinux_policy *newpolicy)
 538 {
 539         int ret = 0;
 540         struct dentry *tmp_parent, *tmp_bool_dir, *tmp_class_dir, *old_dentry;
 541         unsigned int tmp_bool_num, old_bool_num;
 542         char **tmp_bool_names, **old_bool_names;
 543         unsigned int *tmp_bool_values, *old_bool_values;
 544         unsigned long tmp_ino = fsi->last_ino; /* Don't increment last_ino in this function */
 545
 546         tmp_parent = sel_make_disconnected_dir(fsi->sb, &tmp_ino);
 547         if (IS_ERR(tmp_parent))
 548                 return PTR_ERR(tmp_parent);
 549
 550         tmp_ino = fsi->bool_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
 551         tmp_bool_dir = sel_make_dir(tmp_parent, BOOL_DIR_NAME, &tmp_ino);
 552         if (IS_ERR(tmp_bool_dir)) {
 553                 ret = PTR_ERR(tmp_bool_dir);
 554                 goto out;
 555         }
 556
 557         tmp_ino = fsi->class_dir->d_inode->i_ino - 1; /* sel_make_dir will increment and set */
 558         tmp_class_dir = sel_make_dir(tmp_parent, CLASS_DIR_NAME, &tmp_ino);
 559         if (IS_ERR(tmp_class_dir)) {
 560                 ret = PTR_ERR(tmp_class_dir);
 561                 goto out;
 562         }
 563
 564         ret = sel_make_bools(newpolicy, tmp_bool_dir, &tmp_bool_num,
 565                              &tmp_bool_names, &tmp_bool_values);
 566         if (ret) {
 567                 pr_err("SELinux: failed to load policy booleans\n");
 568                 goto out;
 569         }
 570
 571         ret = sel_make_classes(newpolicy, tmp_class_dir,
 572                                &fsi->last_class_ino);
 573         if (ret) {
 574                 pr_err("SELinux: failed to load policy classes\n");
 575                 goto out;
 576         }
 577
 578         /* booleans */
 579         old_dentry = fsi->bool_dir;
 580         lock_rename(tmp_bool_dir, old_dentry);
 581         d_exchange(tmp_bool_dir, fsi->bool_dir);
 582
 583         old_bool_num = fsi->bool_num;
 584         old_bool_names = fsi->bool_pending_names;
 585         old_bool_values = fsi->bool_pending_values;
 586
 587         fsi->bool_num = tmp_bool_num;
 588         fsi->bool_pending_names = tmp_bool_names;
 589         fsi->bool_pending_values = tmp_bool_values;
 590
 591         sel_remove_old_bool_data(old_bool_num, old_bool_names, old_bool_values);
 592
 593         fsi->bool_dir = tmp_bool_dir;
 594         unlock_rename(tmp_bool_dir, old_dentry);
 595
 596         /* classes */
 597         old_dentry = fsi->class_dir;
 598         lock_rename(tmp_class_dir, old_dentry);
 599         d_exchange(tmp_class_dir, fsi->class_dir);
 600         fsi->class_dir = tmp_class_dir;
 601         unlock_rename(tmp_class_dir, old_dentry);
 602
 603 out:
 604         /* Since the other temporary dirs are children of tmp_parent
 605          * this will handle all the cleanup in the case of a failure before
 606          * the swapover
 607          */
 608         sel_remove_entries(tmp_parent);
 609         dput(tmp_parent); /* d_genocide() only handles the children */
 610
 611         return ret;
 612 }
 613
 614 static ssize_t sel_write_load(struct file *file, const char __user *buf,
 615                               size_t count, loff_t *ppos)
 616
 617 {
 618         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 619         struct selinux_load_state load_state;
 620         ssize_t length;
 621         void *data = NULL;
 622
 623         mutex_lock(&fsi->state->policy_mutex);
 624
 625         length = avc_has_perm(&selinux_state,
 626                               current_sid(), SECINITSID_SECURITY,
 627                               SECCLASS_SECURITY, SECURITY__LOAD_POLICY, NULL);
 628         if (length)
 629                 goto out;
 630
 631         /* No partial writes. */
 632         length = -EINVAL;
 633         if (*ppos != 0)
 634                 goto out;
 635
 636         length = -ENOMEM;
 637         data = vmalloc(count);
 638         if (!data)
 639                 goto out;
 640
 641         length = -EFAULT;
 642         if (copy_from_user(data, buf, count) != 0)
 643                 goto out;
 644
 645         length = security_load_policy(fsi->state, data, count, &load_state);
 646         if (length) {
 647                 pr_warn_ratelimited("SELinux: failed to load policy\n");
 648                 goto out;
 649         }
 650
 651         length = sel_make_policy_nodes(fsi, load_state.policy);
 652         if (length) {
 653                 selinux_policy_cancel(fsi->state, &load_state);
 654                 goto out;
 655         }
 656
 657         selinux_policy_commit(fsi->state, &load_state);
 658
 659         length = count;
 660
 661         audit_log(audit_context(), GFP_KERNEL, AUDIT_MAC_POLICY_LOAD,
 662                 "auid=%u ses=%u lsm=selinux res=1",
 663                 from_kuid(&init_user_ns, audit_get_loginuid(current)),
 664                 audit_get_sessionid(current));
 665 out:
 666         mutex_unlock(&fsi->state->policy_mutex);
 667         vfree(data);
 668         return length;
 669 }
 670
 671 static const struct file_operations sel_load_ops = {
 672         .write          = sel_write_load,
 673         .llseek         = generic_file_llseek,
 674 };
 675
 676 static ssize_t sel_write_context(struct file *file, char *buf, size_t size)
 677 {
 678         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 679         struct selinux_state *state = fsi->state;
 680         char *canon = NULL;
 681         u32 sid, len;
 682         ssize_t length;
 683
 684         length = avc_has_perm(&selinux_state,
 685                               current_sid(), SECINITSID_SECURITY,
 686                               SECCLASS_SECURITY, SECURITY__CHECK_CONTEXT, NULL);
 687         if (length)
 688                 goto out;
 689
 690         length = security_context_to_sid(state, buf, size, &sid, GFP_KERNEL);
 691         if (length)
 692                 goto out;
 693
 694         length = security_sid_to_context(state, sid, &canon, &len);
 695         if (length)
 696                 goto out;
 697
 698         length = -ERANGE;
 699         if (len > SIMPLE_TRANSACTION_LIMIT) {
 700                 pr_err("SELinux: %s:  context size (%u) exceeds "
 701                         "payload max\n", __func__, len);
 702                 goto out;
 703         }
 704
 705         memcpy(buf, canon, len);
 706         length = len;
 707 out:
 708         kfree(canon);
 709         return length;
 710 }
 711
 712 static ssize_t sel_read_checkreqprot(struct file *filp, char __user *buf,
 713                                      size_t count, loff_t *ppos)
 714 {
 715         struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
 716         char tmpbuf[TMPBUFLEN];
 717         ssize_t length;
 718
 719         length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
 720                            checkreqprot_get(fsi->state));
 721         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
 722 }
 723
 724 static ssize_t sel_write_checkreqprot(struct file *file, const char __user *buf,
 725                                       size_t count, loff_t *ppos)
 726 {
 727         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 728         char *page;
 729         ssize_t length;
 730         unsigned int new_value;
 731
 732         length = avc_has_perm(&selinux_state,
 733                               current_sid(), SECINITSID_SECURITY,
 734                               SECCLASS_SECURITY, SECURITY__SETCHECKREQPROT,
 735                               NULL);
 736         if (length)
 737                 return length;
 738
 739         if (count >= PAGE_SIZE)
 740                 return -ENOMEM;
 741
 742         /* No partial writes. */
 743         if (*ppos != 0)
 744                 return -EINVAL;
 745
 746         page = memdup_user_nul(buf, count);
 747         if (IS_ERR(page))
 748                 return PTR_ERR(page);
 749
 750         length = -EINVAL;
 751         if (sscanf(page, "%u", &new_value) != 1)
 752                 goto out;
 753
 754         if (new_value) {
 755                 char comm[sizeof(current->comm)];
 756
 757                 memcpy(comm, current->comm, sizeof(comm));
 758                 pr_warn_once("SELinux: %s (%d) set checkreqprot to 1. This is deprecated and will be rejected in a future kernel release.\n",
 759                              comm, current->pid);
 760         }
 761
 762         checkreqprot_set(fsi->state, (new_value ? 1 : 0));
 763         length = count;
 764 out:
 765         kfree(page);
 766         return length;
 767 }
 768 static const struct file_operations sel_checkreqprot_ops = {
 769         .read           = sel_read_checkreqprot,
 770         .write          = sel_write_checkreqprot,
 771         .llseek         = generic_file_llseek,
 772 };
 773
 774 static ssize_t sel_write_validatetrans(struct file *file,
 775                                         const char __user *buf,
 776                                         size_t count, loff_t *ppos)
 777 {
 778         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 779         struct selinux_state *state = fsi->state;
 780         char *oldcon = NULL, *newcon = NULL, *taskcon = NULL;
 781         char *req = NULL;
 782         u32 osid, nsid, tsid;
 783         u16 tclass;
 784         int rc;
 785
 786         rc = avc_has_perm(&selinux_state,
 787                           current_sid(), SECINITSID_SECURITY,
 788                           SECCLASS_SECURITY, SECURITY__VALIDATE_TRANS, NULL);
 789         if (rc)
 790                 goto out;
 791
 792         rc = -ENOMEM;
 793         if (count >= PAGE_SIZE)
 794                 goto out;
 795
 796         /* No partial writes. */
 797         rc = -EINVAL;
 798         if (*ppos != 0)
 799                 goto out;
 800
 801         req = memdup_user_nul(buf, count);
 802         if (IS_ERR(req)) {
 803                 rc = PTR_ERR(req);
 804                 req = NULL;
 805                 goto out;
 806         }
 807
 808         rc = -ENOMEM;
 809         oldcon = kzalloc(count + 1, GFP_KERNEL);
 810         if (!oldcon)
 811                 goto out;
 812
 813         newcon = kzalloc(count + 1, GFP_KERNEL);
 814         if (!newcon)
 815                 goto out;
 816
 817         taskcon = kzalloc(count + 1, GFP_KERNEL);
 818         if (!taskcon)
 819                 goto out;
 820
 821         rc = -EINVAL;
 822         if (sscanf(req, "%s %s %hu %s", oldcon, newcon, &tclass, taskcon) != 4)
 823                 goto out;
 824
 825         rc = security_context_str_to_sid(state, oldcon, &osid, GFP_KERNEL);
 826         if (rc)
 827                 goto out;
 828
 829         rc = security_context_str_to_sid(state, newcon, &nsid, GFP_KERNEL);
 830         if (rc)
 831                 goto out;
 832
 833         rc = security_context_str_to_sid(state, taskcon, &tsid, GFP_KERNEL);
 834         if (rc)
 835                 goto out;
 836
 837         rc = security_validate_transition_user(state, osid, nsid, tsid, tclass);
 838         if (!rc)
 839                 rc = count;
 840 out:
 841         kfree(req);
 842         kfree(oldcon);
 843         kfree(newcon);
 844         kfree(taskcon);
 845         return rc;
 846 }
 847
 848 static const struct file_operations sel_transition_ops = {
 849         .write          = sel_write_validatetrans,
 850         .llseek         = generic_file_llseek,
 851 };
 852
 853 /*
 854  * Remaining nodes use transaction based IO methods like nfsd/nfsctl.c
 855  */
 856 static ssize_t sel_write_access(struct file *file, char *buf, size_t size);
 857 static ssize_t sel_write_create(struct file *file, char *buf, size_t size);
 858 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size);
 859 static ssize_t sel_write_user(struct file *file, char *buf, size_t size);
 860 static ssize_t sel_write_member(struct file *file, char *buf, size_t size);
 861
 862 static ssize_t (*const write_op[])(struct file *, char *, size_t) = {
 863         [SEL_ACCESS] = sel_write_access,
 864         [SEL_CREATE] = sel_write_create,
 865         [SEL_RELABEL] = sel_write_relabel,
 866         [SEL_USER] = sel_write_user,
 867         [SEL_MEMBER] = sel_write_member,
 868         [SEL_CONTEXT] = sel_write_context,
 869 };
 870
 871 static ssize_t selinux_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 872 {
 873         ino_t ino = file_inode(file)->i_ino;
 874         char *data;
 875         ssize_t rv;
 876
 877         if (ino >= ARRAY_SIZE(write_op) || !write_op[ino])
 878                 return -EINVAL;
 879
 880         data = simple_transaction_get(file, buf, size);
 881         if (IS_ERR(data))
 882                 return PTR_ERR(data);
 883
 884         rv = write_op[ino](file, data, size);
 885         if (rv > 0) {
 886                 simple_transaction_set(file, rv);
 887                 rv = size;
 888         }
 889         return rv;
 890 }
 891
 892 static const struct file_operations transaction_ops = {
 893         .write          = selinux_transaction_write,
 894         .read           = simple_transaction_read,
 895         .release        = simple_transaction_release,
 896         .llseek         = generic_file_llseek,
 897 };
 898
 899 /*
 900  * payload - write methods
 901  * If the method has a response, the response should be put in buf,
 902  * and the length returned.  Otherwise return 0 or and -error.
 903  */
 904
 905 static ssize_t sel_write_access(struct file *file, char *buf, size_t size)
 906 {
 907         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 908         struct selinux_state *state = fsi->state;
 909         char *scon = NULL, *tcon = NULL;
 910         u32 ssid, tsid;
 911         u16 tclass;
 912         struct av_decision avd;
 913         ssize_t length;
 914
 915         length = avc_has_perm(&selinux_state,
 916                               current_sid(), SECINITSID_SECURITY,
 917                               SECCLASS_SECURITY, SECURITY__COMPUTE_AV, NULL);
 918         if (length)
 919                 goto out;
 920
 921         length = -ENOMEM;
 922         scon = kzalloc(size + 1, GFP_KERNEL);
 923         if (!scon)
 924                 goto out;
 925
 926         length = -ENOMEM;
 927         tcon = kzalloc(size + 1, GFP_KERNEL);
 928         if (!tcon)
 929                 goto out;
 930
 931         length = -EINVAL;
 932         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
 933                 goto out;
 934
 935         length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
 936         if (length)
 937                 goto out;
 938
 939         length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
 940         if (length)
 941                 goto out;
 942
 943         security_compute_av_user(state, ssid, tsid, tclass, &avd);
 944
 945         length = scnprintf(buf, SIMPLE_TRANSACTION_LIMIT,
 946                           "%x %x %x %x %u %x",
 947                           avd.allowed, 0xffffffff,
 948                           avd.auditallow, avd.auditdeny,
 949                           avd.seqno, avd.flags);
 950 out:
 951         kfree(tcon);
 952         kfree(scon);
 953         return length;
 954 }
 955
 956 static ssize_t sel_write_create(struct file *file, char *buf, size_t size)
 957 {
 958         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
 959         struct selinux_state *state = fsi->state;
 960         char *scon = NULL, *tcon = NULL;
 961         char *namebuf = NULL, *objname = NULL;
 962         u32 ssid, tsid, newsid;
 963         u16 tclass;
 964         ssize_t length;
 965         char *newcon = NULL;
 966         u32 len;
 967         int nargs;
 968
 969         length = avc_has_perm(&selinux_state,
 970                               current_sid(), SECINITSID_SECURITY,
 971                               SECCLASS_SECURITY, SECURITY__COMPUTE_CREATE,
 972                               NULL);
 973         if (length)
 974                 goto out;
 975
 976         length = -ENOMEM;
 977         scon = kzalloc(size + 1, GFP_KERNEL);
 978         if (!scon)
 979                 goto out;
 980
 981         length = -ENOMEM;
 982         tcon = kzalloc(size + 1, GFP_KERNEL);
 983         if (!tcon)
 984                 goto out;
 985
 986         length = -ENOMEM;
 987         namebuf = kzalloc(size + 1, GFP_KERNEL);
 988         if (!namebuf)
 989                 goto out;
 990
 991         length = -EINVAL;
 992         nargs = sscanf(buf, "%s %s %hu %s", scon, tcon, &tclass, namebuf);
 993         if (nargs < 3 || nargs > 4)
 994                 goto out;
 995         if (nargs == 4) {
 996                 /*
 997                  * If and when the name of new object to be queried contains
 998                  * either whitespace or multibyte characters, they shall be
 999                  * encoded based on the percentage-encoding rule.
1000                  * If not encoded, the sscanf logic picks up only left-half
1001                  * of the supplied name; splitted by a whitespace unexpectedly.
1002                  */
1003                 char   *r, *w;
1004                 int     c1, c2;
1005
1006                 r = w = namebuf;
1007                 do {
1008                         c1 = *r++;
1009                         if (c1 == '+')
1010                                 c1 = ' ';
1011                         else if (c1 == '%') {
1012                                 c1 = hex_to_bin(*r++);
1013                                 if (c1 < 0)
1014                                         goto out;
1015                                 c2 = hex_to_bin(*r++);
1016                                 if (c2 < 0)
1017                                         goto out;
1018                                 c1 = (c1 << 4) | c2;
1019                         }
1020                         *w++ = c1;
1021                 } while (c1 != '\0');
1022
1023                 objname = namebuf;
1024         }
1025
1026         length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
1027         if (length)
1028                 goto out;
1029
1030         length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
1031         if (length)
1032                 goto out;
1033
1034         length = security_transition_sid_user(state, ssid, tsid, tclass,
1035                                               objname, &newsid);
1036         if (length)
1037                 goto out;
1038
1039         length = security_sid_to_context(state, newsid, &newcon, &len);
1040         if (length)
1041                 goto out;
1042
1043         length = -ERANGE;
1044         if (len > SIMPLE_TRANSACTION_LIMIT) {
1045                 pr_err("SELinux: %s:  context size (%u) exceeds "
1046                         "payload max\n", __func__, len);
1047                 goto out;
1048         }
1049
1050         memcpy(buf, newcon, len);
1051         length = len;
1052 out:
1053         kfree(newcon);
1054         kfree(namebuf);
1055         kfree(tcon);
1056         kfree(scon);
1057         return length;
1058 }
1059
1060 static ssize_t sel_write_relabel(struct file *file, char *buf, size_t size)
1061 {
1062         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1063         struct selinux_state *state = fsi->state;
1064         char *scon = NULL, *tcon = NULL;
1065         u32 ssid, tsid, newsid;
1066         u16 tclass;
1067         ssize_t length;
1068         char *newcon = NULL;
1069         u32 len;
1070
1071         length = avc_has_perm(&selinux_state,
1072                               current_sid(), SECINITSID_SECURITY,
1073                               SECCLASS_SECURITY, SECURITY__COMPUTE_RELABEL,
1074                               NULL);
1075         if (length)
1076                 goto out;
1077
1078         length = -ENOMEM;
1079         scon = kzalloc(size + 1, GFP_KERNEL);
1080         if (!scon)
1081                 goto out;
1082
1083         length = -ENOMEM;
1084         tcon = kzalloc(size + 1, GFP_KERNEL);
1085         if (!tcon)
1086                 goto out;
1087
1088         length = -EINVAL;
1089         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1090                 goto out;
1091
1092         length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
1093         if (length)
1094                 goto out;
1095
1096         length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
1097         if (length)
1098                 goto out;
1099
1100         length = security_change_sid(state, ssid, tsid, tclass, &newsid);
1101         if (length)
1102                 goto out;
1103
1104         length = security_sid_to_context(state, newsid, &newcon, &len);
1105         if (length)
1106                 goto out;
1107
1108         length = -ERANGE;
1109         if (len > SIMPLE_TRANSACTION_LIMIT)
1110                 goto out;
1111
1112         memcpy(buf, newcon, len);
1113         length = len;
1114 out:
1115         kfree(newcon);
1116         kfree(tcon);
1117         kfree(scon);
1118         return length;
1119 }
1120
1121 static ssize_t sel_write_user(struct file *file, char *buf, size_t size)
1122 {
1123         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1124         struct selinux_state *state = fsi->state;
1125         char *con = NULL, *user = NULL, *ptr;
1126         u32 sid, *sids = NULL;
1127         ssize_t length;
1128         char *newcon;
1129         int i, rc;
1130         u32 len, nsids;
1131
1132         length = avc_has_perm(&selinux_state,
1133                               current_sid(), SECINITSID_SECURITY,
1134                               SECCLASS_SECURITY, SECURITY__COMPUTE_USER,
1135                               NULL);
1136         if (length)
1137                 goto out;
1138
1139         length = -ENOMEM;
1140         con = kzalloc(size + 1, GFP_KERNEL);
1141         if (!con)
1142                 goto out;
1143
1144         length = -ENOMEM;
1145         user = kzalloc(size + 1, GFP_KERNEL);
1146         if (!user)
1147                 goto out;
1148
1149         length = -EINVAL;
1150         if (sscanf(buf, "%s %s", con, user) != 2)
1151                 goto out;
1152
1153         length = security_context_str_to_sid(state, con, &sid, GFP_KERNEL);
1154         if (length)
1155                 goto out;
1156
1157         length = security_get_user_sids(state, sid, user, &sids, &nsids);
1158         if (length)
1159                 goto out;
1160
1161         length = sprintf(buf, "%u", nsids) + 1;
1162         ptr = buf + length;
1163         for (i = 0; i < nsids; i++) {
1164                 rc = security_sid_to_context(state, sids[i], &newcon, &len);
1165                 if (rc) {
1166                         length = rc;
1167                         goto out;
1168                 }
1169                 if ((length + len) >= SIMPLE_TRANSACTION_LIMIT) {
1170                         kfree(newcon);
1171                         length = -ERANGE;
1172                         goto out;
1173                 }
1174                 memcpy(ptr, newcon, len);
1175                 kfree(newcon);
1176                 ptr += len;
1177                 length += len;
1178         }
1179 out:
1180         kfree(sids);
1181         kfree(user);
1182         kfree(con);
1183         return length;
1184 }
1185
1186 static ssize_t sel_write_member(struct file *file, char *buf, size_t size)
1187 {
1188         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1189         struct selinux_state *state = fsi->state;
1190         char *scon = NULL, *tcon = NULL;
1191         u32 ssid, tsid, newsid;
1192         u16 tclass;
1193         ssize_t length;
1194         char *newcon = NULL;
1195         u32 len;
1196
1197         length = avc_has_perm(&selinux_state,
1198                               current_sid(), SECINITSID_SECURITY,
1199                               SECCLASS_SECURITY, SECURITY__COMPUTE_MEMBER,
1200                               NULL);
1201         if (length)
1202                 goto out;
1203
1204         length = -ENOMEM;
1205         scon = kzalloc(size + 1, GFP_KERNEL);
1206         if (!scon)
1207                 goto out;
1208
1209         length = -ENOMEM;
1210         tcon = kzalloc(size + 1, GFP_KERNEL);
1211         if (!tcon)
1212                 goto out;
1213
1214         length = -EINVAL;
1215         if (sscanf(buf, "%s %s %hu", scon, tcon, &tclass) != 3)
1216                 goto out;
1217
1218         length = security_context_str_to_sid(state, scon, &ssid, GFP_KERNEL);
1219         if (length)
1220                 goto out;
1221
1222         length = security_context_str_to_sid(state, tcon, &tsid, GFP_KERNEL);
1223         if (length)
1224                 goto out;
1225
1226         length = security_member_sid(state, ssid, tsid, tclass, &newsid);
1227         if (length)
1228                 goto out;
1229
1230         length = security_sid_to_context(state, newsid, &newcon, &len);
1231         if (length)
1232                 goto out;
1233
1234         length = -ERANGE;
1235         if (len > SIMPLE_TRANSACTION_LIMIT) {
1236                 pr_err("SELinux: %s:  context size (%u) exceeds "
1237                         "payload max\n", __func__, len);
1238                 goto out;
1239         }
1240
1241         memcpy(buf, newcon, len);
1242         length = len;
1243 out:
1244         kfree(newcon);
1245         kfree(tcon);
1246         kfree(scon);
1247         return length;
1248 }
1249
1250 static struct inode *sel_make_inode(struct super_block *sb, int mode)
1251 {
1252         struct inode *ret = new_inode(sb);
1253
1254         if (ret) {
1255                 ret->i_mode = mode;
1256                 ret->i_atime = ret->i_mtime = ret->i_ctime = current_time(ret);
1257         }
1258         return ret;
1259 }
1260
1261 static ssize_t sel_read_bool(struct file *filep, char __user *buf,
1262                              size_t count, loff_t *ppos)
1263 {
1264         struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1265         char *page = NULL;
1266         ssize_t length;
1267         ssize_t ret;
1268         int cur_enforcing;
1269         unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1270         const char *name = filep->f_path.dentry->d_name.name;
1271
1272         mutex_lock(&fsi->state->policy_mutex);
1273
1274         ret = -EINVAL;
1275         if (index >= fsi->bool_num || strcmp(name,
1276                                              fsi->bool_pending_names[index]))
1277                 goto out_unlock;
1278
1279         ret = -ENOMEM;
1280         page = (char *)get_zeroed_page(GFP_KERNEL);
1281         if (!page)
1282                 goto out_unlock;
1283
1284         cur_enforcing = security_get_bool_value(fsi->state, index);
1285         if (cur_enforcing < 0) {
1286                 ret = cur_enforcing;
1287                 goto out_unlock;
1288         }
1289         length = scnprintf(page, PAGE_SIZE, "%d %d", cur_enforcing,
1290                           fsi->bool_pending_values[index]);
1291         mutex_unlock(&fsi->state->policy_mutex);
1292         ret = simple_read_from_buffer(buf, count, ppos, page, length);
1293 out_free:
1294         free_page((unsigned long)page);
1295         return ret;
1296
1297 out_unlock:
1298         mutex_unlock(&fsi->state->policy_mutex);
1299         goto out_free;
1300 }
1301
1302 static ssize_t sel_write_bool(struct file *filep, const char __user *buf,
1303                               size_t count, loff_t *ppos)
1304 {
1305         struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1306         char *page = NULL;
1307         ssize_t length;
1308         int new_value;
1309         unsigned index = file_inode(filep)->i_ino & SEL_INO_MASK;
1310         const char *name = filep->f_path.dentry->d_name.name;
1311
1312         if (count >= PAGE_SIZE)
1313                 return -ENOMEM;
1314
1315         /* No partial writes. */
1316         if (*ppos != 0)
1317                 return -EINVAL;
1318
1319         page = memdup_user_nul(buf, count);
1320         if (IS_ERR(page))
1321                 return PTR_ERR(page);
1322
1323         mutex_lock(&fsi->state->policy_mutex);
1324
1325         length = avc_has_perm(&selinux_state,
1326                               current_sid(), SECINITSID_SECURITY,
1327                               SECCLASS_SECURITY, SECURITY__SETBOOL,
1328                               NULL);
1329         if (length)
1330                 goto out;
1331
1332         length = -EINVAL;
1333         if (index >= fsi->bool_num || strcmp(name,
1334                                              fsi->bool_pending_names[index]))
1335                 goto out;
1336
1337         length = -EINVAL;
1338         if (sscanf(page, "%d", &new_value) != 1)
1339                 goto out;
1340
1341         if (new_value)
1342                 new_value = 1;
1343
1344         fsi->bool_pending_values[index] = new_value;
1345         length = count;
1346
1347 out:
1348         mutex_unlock(&fsi->state->policy_mutex);
1349         kfree(page);
1350         return length;
1351 }
1352
1353 static const struct file_operations sel_bool_ops = {
1354         .read           = sel_read_bool,
1355         .write          = sel_write_bool,
1356         .llseek         = generic_file_llseek,
1357 };
1358
1359 static ssize_t sel_commit_bools_write(struct file *filep,
1360                                       const char __user *buf,
1361                                       size_t count, loff_t *ppos)
1362 {
1363         struct selinux_fs_info *fsi = file_inode(filep)->i_sb->s_fs_info;
1364         char *page = NULL;
1365         ssize_t length;
1366         int new_value;
1367
1368         if (count >= PAGE_SIZE)
1369                 return -ENOMEM;
1370
1371         /* No partial writes. */
1372         if (*ppos != 0)
1373                 return -EINVAL;
1374
1375         page = memdup_user_nul(buf, count);
1376         if (IS_ERR(page))
1377                 return PTR_ERR(page);
1378
1379         mutex_lock(&fsi->state->policy_mutex);
1380
1381         length = avc_has_perm(&selinux_state,
1382                               current_sid(), SECINITSID_SECURITY,
1383                               SECCLASS_SECURITY, SECURITY__SETBOOL,
1384                               NULL);
1385         if (length)
1386                 goto out;
1387
1388         length = -EINVAL;
1389         if (sscanf(page, "%d", &new_value) != 1)
1390                 goto out;
1391
1392         length = 0;
1393         if (new_value && fsi->bool_pending_values)
1394                 length = security_set_bools(fsi->state, fsi->bool_num,
1395                                             fsi->bool_pending_values);
1396
1397         if (!length)
1398                 length = count;
1399
1400 out:
1401         mutex_unlock(&fsi->state->policy_mutex);
1402         kfree(page);
1403         return length;
1404 }
1405
1406 static const struct file_operations sel_commit_bools_ops = {
1407         .write          = sel_commit_bools_write,
1408         .llseek         = generic_file_llseek,
1409 };
1410
1411 static void sel_remove_entries(struct dentry *de)
1412 {
1413         d_genocide(de);
1414         shrink_dcache_parent(de);
1415 }
1416
1417 static int sel_make_bools(struct selinux_policy *newpolicy, struct dentry *bool_dir,
1418                           unsigned int *bool_num, char ***bool_pending_names,
1419                           unsigned int **bool_pending_values)
1420 {
1421         int ret;
1422         ssize_t len;
1423         struct dentry *dentry = NULL;
1424         struct inode *inode = NULL;
1425         struct inode_security_struct *isec;
1426         char **names = NULL, *page;
1427         u32 i, num;
1428         int *values = NULL;
1429         u32 sid;
1430
1431         ret = -ENOMEM;
1432         page = (char *)get_zeroed_page(GFP_KERNEL);
1433         if (!page)
1434                 goto out;
1435
1436         ret = security_get_bools(newpolicy, &num, &names, &values);
1437         if (ret)
1438                 goto out;
1439
1440         for (i = 0; i < num; i++) {
1441                 ret = -ENOMEM;
1442                 dentry = d_alloc_name(bool_dir, names[i]);
1443                 if (!dentry)
1444                         goto out;
1445
1446                 ret = -ENOMEM;
1447                 inode = sel_make_inode(bool_dir->d_sb, S_IFREG | S_IRUGO | S_IWUSR);
1448                 if (!inode) {
1449                         dput(dentry);
1450                         goto out;
1451                 }
1452
1453                 ret = -ENAMETOOLONG;
1454                 len = snprintf(page, PAGE_SIZE, "/%s/%s", BOOL_DIR_NAME, names[i]);
1455                 if (len >= PAGE_SIZE) {
1456                         dput(dentry);
1457                         iput(inode);
1458                         goto out;
1459                 }
1460
1461                 isec = selinux_inode(inode);
1462                 ret = selinux_policy_genfs_sid(newpolicy, "selinuxfs", page,
1463                                          SECCLASS_FILE, &sid);
1464                 if (ret) {
1465                         pr_warn_ratelimited("SELinux: no sid found, defaulting to security isid for %s\n",
1466                                            page);
1467                         sid = SECINITSID_SECURITY;
1468                 }
1469
1470                 isec->sid = sid;
1471                 isec->initialized = LABEL_INITIALIZED;
1472                 inode->i_fop = &sel_bool_ops;
1473                 inode->i_ino = i|SEL_BOOL_INO_OFFSET;
1474                 d_add(dentry, inode);
1475         }
1476         *bool_num = num;
1477         *bool_pending_names = names;
1478         *bool_pending_values = values;
1479
1480         free_page((unsigned long)page);
1481         return 0;
1482 out:
1483         free_page((unsigned long)page);
1484
1485         if (names) {
1486                 for (i = 0; i < num; i++)
1487                         kfree(names[i]);
1488                 kfree(names);
1489         }
1490         kfree(values);
1491         sel_remove_entries(bool_dir);
1492
1493         return ret;
1494 }
1495
1496 static ssize_t sel_read_avc_cache_threshold(struct file *filp, char __user *buf,
1497                                             size_t count, loff_t *ppos)
1498 {
1499         struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1500         struct selinux_state *state = fsi->state;
1501         char tmpbuf[TMPBUFLEN];
1502         ssize_t length;
1503
1504         length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
1505                            avc_get_cache_threshold(state->avc));
1506         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1507 }
1508
1509 static ssize_t sel_write_avc_cache_threshold(struct file *file,
1510                                              const char __user *buf,
1511                                              size_t count, loff_t *ppos)
1512
1513 {
1514         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1515         struct selinux_state *state = fsi->state;
1516         char *page;
1517         ssize_t ret;
1518         unsigned int new_value;
1519
1520         ret = avc_has_perm(&selinux_state,
1521                            current_sid(), SECINITSID_SECURITY,
1522                            SECCLASS_SECURITY, SECURITY__SETSECPARAM,
1523                            NULL);
1524         if (ret)
1525                 return ret;
1526
1527         if (count >= PAGE_SIZE)
1528                 return -ENOMEM;
1529
1530         /* No partial writes. */
1531         if (*ppos != 0)
1532                 return -EINVAL;
1533
1534         page = memdup_user_nul(buf, count);
1535         if (IS_ERR(page))
1536                 return PTR_ERR(page);
1537
1538         ret = -EINVAL;
1539         if (sscanf(page, "%u", &new_value) != 1)
1540                 goto out;
1541
1542         avc_set_cache_threshold(state->avc, new_value);
1543
1544         ret = count;
1545 out:
1546         kfree(page);
1547         return ret;
1548 }
1549
1550 static ssize_t sel_read_avc_hash_stats(struct file *filp, char __user *buf,
1551                                        size_t count, loff_t *ppos)
1552 {
1553         struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1554         struct selinux_state *state = fsi->state;
1555         char *page;
1556         ssize_t length;
1557
1558         page = (char *)__get_free_page(GFP_KERNEL);
1559         if (!page)
1560                 return -ENOMEM;
1561
1562         length = avc_get_hash_stats(state->avc, page);
1563         if (length >= 0)
1564                 length = simple_read_from_buffer(buf, count, ppos, page, length);
1565         free_page((unsigned long)page);
1566
1567         return length;
1568 }
1569
1570 static ssize_t sel_read_sidtab_hash_stats(struct file *filp, char __user *buf,
1571                                         size_t count, loff_t *ppos)
1572 {
1573         struct selinux_fs_info *fsi = file_inode(filp)->i_sb->s_fs_info;
1574         struct selinux_state *state = fsi->state;
1575         char *page;
1576         ssize_t length;
1577
1578         page = (char *)__get_free_page(GFP_KERNEL);
1579         if (!page)
1580                 return -ENOMEM;
1581
1582         length = security_sidtab_hash_stats(state, page);
1583         if (length >= 0)
1584                 length = simple_read_from_buffer(buf, count, ppos, page,
1585                                                 length);
1586         free_page((unsigned long)page);
1587
1588         return length;
1589 }
1590
1591 static const struct file_operations sel_sidtab_hash_stats_ops = {
1592         .read           = sel_read_sidtab_hash_stats,
1593         .llseek         = generic_file_llseek,
1594 };
1595
1596 static const struct file_operations sel_avc_cache_threshold_ops = {
1597         .read           = sel_read_avc_cache_threshold,
1598         .write          = sel_write_avc_cache_threshold,
1599         .llseek         = generic_file_llseek,
1600 };
1601
1602 static const struct file_operations sel_avc_hash_stats_ops = {
1603         .read           = sel_read_avc_hash_stats,
1604         .llseek         = generic_file_llseek,
1605 };
1606
1607 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1608 static struct avc_cache_stats *sel_avc_get_stat_idx(loff_t *idx)
1609 {
1610         int cpu;
1611
1612         for (cpu = *idx; cpu < nr_cpu_ids; ++cpu) {
1613                 if (!cpu_possible(cpu))
1614                         continue;
1615                 *idx = cpu + 1;
1616                 return &per_cpu(avc_cache_stats, cpu);
1617         }
1618         (*idx)++;
1619         return NULL;
1620 }
1621
1622 static void *sel_avc_stats_seq_start(struct seq_file *seq, loff_t *pos)
1623 {
1624         loff_t n = *pos - 1;
1625
1626         if (*pos == 0)
1627                 return SEQ_START_TOKEN;
1628
1629         return sel_avc_get_stat_idx(&n);
1630 }
1631
1632 static void *sel_avc_stats_seq_next(struct seq_file *seq, void *v, loff_t *pos)
1633 {
1634         return sel_avc_get_stat_idx(pos);
1635 }
1636
1637 static int sel_avc_stats_seq_show(struct seq_file *seq, void *v)
1638 {
1639         struct avc_cache_stats *st = v;
1640
1641         if (v == SEQ_START_TOKEN) {
1642                 seq_puts(seq,
1643                          "lookups hits misses allocations reclaims frees\n");
1644         } else {
1645                 unsigned int lookups = st->lookups;
1646                 unsigned int misses = st->misses;
1647                 unsigned int hits = lookups - misses;
1648                 seq_printf(seq, "%u %u %u %u %u %u\n", lookups,
1649                            hits, misses, st->allocations,
1650                            st->reclaims, st->frees);
1651         }
1652         return 0;
1653 }
1654
1655 static void sel_avc_stats_seq_stop(struct seq_file *seq, void *v)
1656 { }
1657
1658 static const struct seq_operations sel_avc_cache_stats_seq_ops = {
1659         .start          = sel_avc_stats_seq_start,
1660         .next           = sel_avc_stats_seq_next,
1661         .show           = sel_avc_stats_seq_show,
1662         .stop           = sel_avc_stats_seq_stop,
1663 };
1664
1665 static int sel_open_avc_cache_stats(struct inode *inode, struct file *file)
1666 {
1667         return seq_open(file, &sel_avc_cache_stats_seq_ops);
1668 }
1669
1670 static const struct file_operations sel_avc_cache_stats_ops = {
1671         .open           = sel_open_avc_cache_stats,
1672         .read           = seq_read,
1673         .llseek         = seq_lseek,
1674         .release        = seq_release,
1675 };
1676 #endif
1677
1678 static int sel_make_avc_files(struct dentry *dir)
1679 {
1680         struct super_block *sb = dir->d_sb;
1681         struct selinux_fs_info *fsi = sb->s_fs_info;
1682         int i;
1683         static const struct tree_descr files[] = {
1684                 { "cache_threshold",
1685                   &sel_avc_cache_threshold_ops, S_IRUGO|S_IWUSR },
1686                 { "hash_stats", &sel_avc_hash_stats_ops, S_IRUGO },
1687 #ifdef CONFIG_SECURITY_SELINUX_AVC_STATS
1688                 { "cache_stats", &sel_avc_cache_stats_ops, S_IRUGO },
1689 #endif
1690         };
1691
1692         for (i = 0; i < ARRAY_SIZE(files); i++) {
1693                 struct inode *inode;
1694                 struct dentry *dentry;
1695
1696                 dentry = d_alloc_name(dir, files[i].name);
1697                 if (!dentry)
1698                         return -ENOMEM;
1699
1700                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1701                 if (!inode) {
1702                         dput(dentry);
1703                         return -ENOMEM;
1704                 }
1705
1706                 inode->i_fop = files[i].ops;
1707                 inode->i_ino = ++fsi->last_ino;
1708                 d_add(dentry, inode);
1709         }
1710
1711         return 0;
1712 }
1713
1714 static int sel_make_ss_files(struct dentry *dir)
1715 {
1716         struct super_block *sb = dir->d_sb;
1717         struct selinux_fs_info *fsi = sb->s_fs_info;
1718         int i;
1719         static struct tree_descr files[] = {
1720                 { "sidtab_hash_stats", &sel_sidtab_hash_stats_ops, S_IRUGO },
1721         };
1722
1723         for (i = 0; i < ARRAY_SIZE(files); i++) {
1724                 struct inode *inode;
1725                 struct dentry *dentry;
1726
1727                 dentry = d_alloc_name(dir, files[i].name);
1728                 if (!dentry)
1729                         return -ENOMEM;
1730
1731                 inode = sel_make_inode(dir->d_sb, S_IFREG|files[i].mode);
1732                 if (!inode) {
1733                         dput(dentry);
1734                         return -ENOMEM;
1735                 }
1736
1737                 inode->i_fop = files[i].ops;
1738                 inode->i_ino = ++fsi->last_ino;
1739                 d_add(dentry, inode);
1740         }
1741
1742         return 0;
1743 }
1744
1745 static ssize_t sel_read_initcon(struct file *file, char __user *buf,
1746                                 size_t count, loff_t *ppos)
1747 {
1748         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1749         char *con;
1750         u32 sid, len;
1751         ssize_t ret;
1752
1753         sid = file_inode(file)->i_ino&SEL_INO_MASK;
1754         ret = security_sid_to_context(fsi->state, sid, &con, &len);
1755         if (ret)
1756                 return ret;
1757
1758         ret = simple_read_from_buffer(buf, count, ppos, con, len);
1759         kfree(con);
1760         return ret;
1761 }
1762
1763 static const struct file_operations sel_initcon_ops = {
1764         .read           = sel_read_initcon,
1765         .llseek         = generic_file_llseek,
1766 };
1767
1768 static int sel_make_initcon_files(struct dentry *dir)
1769 {
1770         int i;
1771
1772         for (i = 1; i <= SECINITSID_NUM; i++) {
1773                 struct inode *inode;
1774                 struct dentry *dentry;
1775                 const char *s = security_get_initial_sid_context(i);
1776
1777                 if (!s)
1778                         continue;
1779                 dentry = d_alloc_name(dir, s);
1780                 if (!dentry)
1781                         return -ENOMEM;
1782
1783                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1784                 if (!inode) {
1785                         dput(dentry);
1786                         return -ENOMEM;
1787                 }
1788
1789                 inode->i_fop = &sel_initcon_ops;
1790                 inode->i_ino = i|SEL_INITCON_INO_OFFSET;
1791                 d_add(dentry, inode);
1792         }
1793
1794         return 0;
1795 }
1796
1797 static inline unsigned long sel_class_to_ino(u16 class)
1798 {
1799         return (class * (SEL_VEC_MAX + 1)) | SEL_CLASS_INO_OFFSET;
1800 }
1801
1802 static inline u16 sel_ino_to_class(unsigned long ino)
1803 {
1804         return (ino & SEL_INO_MASK) / (SEL_VEC_MAX + 1);
1805 }
1806
1807 static inline unsigned long sel_perm_to_ino(u16 class, u32 perm)
1808 {
1809         return (class * (SEL_VEC_MAX + 1) + perm) | SEL_CLASS_INO_OFFSET;
1810 }
1811
1812 static inline u32 sel_ino_to_perm(unsigned long ino)
1813 {
1814         return (ino & SEL_INO_MASK) % (SEL_VEC_MAX + 1);
1815 }
1816
1817 static ssize_t sel_read_class(struct file *file, char __user *buf,
1818                                 size_t count, loff_t *ppos)
1819 {
1820         unsigned long ino = file_inode(file)->i_ino;
1821         char res[TMPBUFLEN];
1822         ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_class(ino));
1823         return simple_read_from_buffer(buf, count, ppos, res, len);
1824 }
1825
1826 static const struct file_operations sel_class_ops = {
1827         .read           = sel_read_class,
1828         .llseek         = generic_file_llseek,
1829 };
1830
1831 static ssize_t sel_read_perm(struct file *file, char __user *buf,
1832                                 size_t count, loff_t *ppos)
1833 {
1834         unsigned long ino = file_inode(file)->i_ino;
1835         char res[TMPBUFLEN];
1836         ssize_t len = scnprintf(res, sizeof(res), "%d", sel_ino_to_perm(ino));
1837         return simple_read_from_buffer(buf, count, ppos, res, len);
1838 }
1839
1840 static const struct file_operations sel_perm_ops = {
1841         .read           = sel_read_perm,
1842         .llseek         = generic_file_llseek,
1843 };
1844
1845 static ssize_t sel_read_policycap(struct file *file, char __user *buf,
1846                                   size_t count, loff_t *ppos)
1847 {
1848         struct selinux_fs_info *fsi = file_inode(file)->i_sb->s_fs_info;
1849         int value;
1850         char tmpbuf[TMPBUFLEN];
1851         ssize_t length;
1852         unsigned long i_ino = file_inode(file)->i_ino;
1853
1854         value = security_policycap_supported(fsi->state, i_ino & SEL_INO_MASK);
1855         length = scnprintf(tmpbuf, TMPBUFLEN, "%d", value);
1856
1857         return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
1858 }
1859
1860 static const struct file_operations sel_policycap_ops = {
1861         .read           = sel_read_policycap,
1862         .llseek         = generic_file_llseek,
1863 };
1864
1865 static int sel_make_perm_files(struct selinux_policy *newpolicy,
1866                         char *objclass, int classvalue,
1867                         struct dentry *dir)
1868 {
1869         int i, rc, nperms;
1870         char **perms;
1871
1872         rc = security_get_permissions(newpolicy, objclass, &perms, &nperms);
1873         if (rc)
1874                 return rc;
1875
1876         for (i = 0; i < nperms; i++) {
1877                 struct inode *inode;
1878                 struct dentry *dentry;
1879
1880                 rc = -ENOMEM;
1881                 dentry = d_alloc_name(dir, perms[i]);
1882                 if (!dentry)
1883                         goto out;
1884
1885                 rc = -ENOMEM;
1886                 inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1887                 if (!inode) {
1888                         dput(dentry);
1889                         goto out;
1890                 }
1891
1892                 inode->i_fop = &sel_perm_ops;
1893                 /* i+1 since perm values are 1-indexed */
1894                 inode->i_ino = sel_perm_to_ino(classvalue, i + 1);
1895                 d_add(dentry, inode);
1896         }
1897         rc = 0;
1898 out:
1899         for (i = 0; i < nperms; i++)
1900                 kfree(perms[i]);
1901         kfree(perms);
1902         return rc;
1903 }
1904
1905 static int sel_make_class_dir_entries(struct selinux_policy *newpolicy,
1906                                 char *classname, int index,
1907                                 struct dentry *dir)
1908 {
1909         struct super_block *sb = dir->d_sb;
1910         struct selinux_fs_info *fsi = sb->s_fs_info;
1911         struct dentry *dentry = NULL;
1912         struct inode *inode = NULL;
1913         int rc;
1914
1915         dentry = d_alloc_name(dir, "index");
1916         if (!dentry)
1917                 return -ENOMEM;
1918
1919         inode = sel_make_inode(dir->d_sb, S_IFREG|S_IRUGO);
1920         if (!inode) {
1921                 dput(dentry);
1922                 return -ENOMEM;
1923         }
1924
1925         inode->i_fop = &sel_class_ops;
1926         inode->i_ino = sel_class_to_ino(index);
1927         d_add(dentry, inode);
1928
1929         dentry = sel_make_dir(dir, "perms", &fsi->last_class_ino);
1930         if (IS_ERR(dentry))
1931                 return PTR_ERR(dentry);
1932
1933         rc = sel_make_perm_files(newpolicy, classname, index, dentry);
1934
1935         return rc;
1936 }
1937
1938 static int sel_make_classes(struct selinux_policy *newpolicy,
1939                             struct dentry *class_dir,
1940                             unsigned long *last_class_ino)
1941 {
1942
1943         int rc, nclasses, i;
1944         char **classes;
1945
1946         rc = security_get_classes(newpolicy, &classes, &nclasses);
1947         if (rc)
1948                 return rc;
1949
1950         /* +2 since classes are 1-indexed */
1951         *last_class_ino = sel_class_to_ino(nclasses + 2);
1952
1953         for (i = 0; i < nclasses; i++) {
1954                 struct dentry *class_name_dir;
1955
1956                 class_name_dir = sel_make_dir(class_dir, classes[i],
1957                                               last_class_ino);
1958                 if (IS_ERR(class_name_dir)) {
1959                         rc = PTR_ERR(class_name_dir);
1960                         goto out;
1961                 }
1962
1963                 /* i+1 since class values are 1-indexed */
1964                 rc = sel_make_class_dir_entries(newpolicy, classes[i], i + 1,
1965                                 class_name_dir);
1966                 if (rc)
1967                         goto out;
1968         }
1969         rc = 0;
1970 out:
1971         for (i = 0; i < nclasses; i++)
1972                 kfree(classes[i]);
1973         kfree(classes);
1974         return rc;
1975 }
1976
1977 static int sel_make_policycap(struct selinux_fs_info *fsi)
1978 {
1979         unsigned int iter;
1980         struct dentry *dentry = NULL;
1981         struct inode *inode = NULL;
1982
1983         for (iter = 0; iter <= POLICYDB_CAPABILITY_MAX; iter++) {
1984                 if (iter < ARRAY_SIZE(selinux_policycap_names))
1985                         dentry = d_alloc_name(fsi->policycap_dir,
1986                                               selinux_policycap_names[iter]);
1987                 else
1988                         dentry = d_alloc_name(fsi->policycap_dir, "unknown");
1989
1990                 if (dentry == NULL)
1991                         return -ENOMEM;
1992
1993                 inode = sel_make_inode(fsi->sb, S_IFREG | 0444);
1994                 if (inode == NULL) {
1995                         dput(dentry);
1996                         return -ENOMEM;
1997                 }
1998
1999                 inode->i_fop = &sel_policycap_ops;
2000                 inode->i_ino = iter | SEL_POLICYCAP_INO_OFFSET;
2001                 d_add(dentry, inode);
2002         }
2003
2004         return 0;
2005 }
2006
2007 static struct dentry *sel_make_dir(struct dentry *dir, const char *name,
2008                         unsigned long *ino)
2009 {
2010         struct dentry *dentry = d_alloc_name(dir, name);
2011         struct inode *inode;
2012
2013         if (!dentry)
2014                 return ERR_PTR(-ENOMEM);
2015
2016         inode = sel_make_inode(dir->d_sb, S_IFDIR | S_IRUGO | S_IXUGO);
2017         if (!inode) {
2018                 dput(dentry);
2019                 return ERR_PTR(-ENOMEM);
2020         }
2021
2022         inode->i_op = &simple_dir_inode_operations;
2023         inode->i_fop = &simple_dir_operations;
2024         inode->i_ino = ++(*ino);
2025         /* directory inodes start off with i_nlink == 2 (for "." entry) */
2026         inc_nlink(inode);
2027         d_add(dentry, inode);
2028         /* bump link count on parent directory, too */
2029         inc_nlink(d_inode(dir));
2030
2031         return dentry;
2032 }
2033
2034 static struct dentry *sel_make_disconnected_dir(struct super_block *sb,
2035                                                 unsigned long *ino)
2036 {
2037         struct inode *inode = sel_make_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
2038
2039         if (!inode)
2040                 return ERR_PTR(-ENOMEM);
2041
2042         inode->i_op = &simple_dir_inode_operations;
2043         inode->i_fop = &simple_dir_operations;
2044         inode->i_ino = ++(*ino);
2045         /* directory inodes start off with i_nlink == 2 (for "." entry) */
2046         inc_nlink(inode);
2047         return d_obtain_alias(inode);
2048 }
2049
2050 #define NULL_FILE_NAME "null"
2051
2052 static int sel_fill_super(struct super_block *sb, struct fs_context *fc)
2053 {
2054         struct selinux_fs_info *fsi;
2055         int ret;
2056         struct dentry *dentry;
2057         struct inode *inode;
2058         struct inode_security_struct *isec;
2059
2060         static const struct tree_descr selinux_files[] = {
2061                 [SEL_LOAD] = {"load", &sel_load_ops, S_IRUSR|S_IWUSR},
2062                 [SEL_ENFORCE] = {"enforce", &sel_enforce_ops, S_IRUGO|S_IWUSR},
2063                 [SEL_CONTEXT] = {"context", &transaction_ops, S_IRUGO|S_IWUGO},
2064                 [SEL_ACCESS] = {"access", &transaction_ops, S_IRUGO|S_IWUGO},
2065                 [SEL_CREATE] = {"create", &transaction_ops, S_IRUGO|S_IWUGO},
2066                 [SEL_RELABEL] = {"relabel", &transaction_ops, S_IRUGO|S_IWUGO},
2067                 [SEL_USER] = {"user", &transaction_ops, S_IRUGO|S_IWUGO},
2068                 [SEL_POLICYVERS] = {"policyvers", &sel_policyvers_ops, S_IRUGO},
2069                 [SEL_COMMIT_BOOLS] = {"commit_pending_bools", &sel_commit_bools_ops, S_IWUSR},
2070                 [SEL_MLS] = {"mls", &sel_mls_ops, S_IRUGO},
2071                 [SEL_DISABLE] = {"disable", &sel_disable_ops, S_IWUSR},
2072                 [SEL_MEMBER] = {"member", &transaction_ops, S_IRUGO|S_IWUGO},
2073                 [SEL_CHECKREQPROT] = {"checkreqprot", &sel_checkreqprot_ops, S_IRUGO|S_IWUSR},
2074                 [SEL_REJECT_UNKNOWN] = {"reject_unknown", &sel_handle_unknown_ops, S_IRUGO},
2075                 [SEL_DENY_UNKNOWN] = {"deny_unknown", &sel_handle_unknown_ops, S_IRUGO},
2076                 [SEL_STATUS] = {"status", &sel_handle_status_ops, S_IRUGO},
2077                 [SEL_POLICY] = {"policy", &sel_policy_ops, S_IRUGO},
2078                 [SEL_VALIDATE_TRANS] = {"validatetrans", &sel_transition_ops,
2079                                         S_IWUGO},
2080                 /* last one */ {""}
2081         };
2082
2083         ret = selinux_fs_info_create(sb);
2084         if (ret)
2085                 goto err;
2086
2087         ret = simple_fill_super(sb, SELINUX_MAGIC, selinux_files);
2088         if (ret)
2089                 goto err;
2090
2091         fsi = sb->s_fs_info;
2092         fsi->bool_dir = sel_make_dir(sb->s_root, BOOL_DIR_NAME, &fsi->last_ino);
2093         if (IS_ERR(fsi->bool_dir)) {
2094                 ret = PTR_ERR(fsi->bool_dir);
2095                 fsi->bool_dir = NULL;
2096                 goto err;
2097         }
2098
2099         ret = -ENOMEM;
2100         dentry = d_alloc_name(sb->s_root, NULL_FILE_NAME);
2101         if (!dentry)
2102                 goto err;
2103
2104         ret = -ENOMEM;
2105         inode = sel_make_inode(sb, S_IFCHR | S_IRUGO | S_IWUGO);
2106         if (!inode) {
2107                 dput(dentry);
2108                 goto err;
2109         }
2110
2111         inode->i_ino = ++fsi->last_ino;
2112         isec = selinux_inode(inode);
2113         isec->sid = SECINITSID_DEVNULL;
2114         isec->sclass = SECCLASS_CHR_FILE;
2115         isec->initialized = LABEL_INITIALIZED;
2116
2117         init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO, MKDEV(MEM_MAJOR, 3));
2118         d_add(dentry, inode);
2119
2120         dentry = sel_make_dir(sb->s_root, "avc", &fsi->last_ino);
2121         if (IS_ERR(dentry)) {
2122                 ret = PTR_ERR(dentry);
2123                 goto err;
2124         }
2125
2126         ret = sel_make_avc_files(dentry);
2127
2128         dentry = sel_make_dir(sb->s_root, "ss", &fsi->last_ino);
2129         if (IS_ERR(dentry)) {
2130                 ret = PTR_ERR(dentry);
2131                 goto err;
2132         }
2133
2134         ret = sel_make_ss_files(dentry);
2135         if (ret)
2136                 goto err;
2137
2138         dentry = sel_make_dir(sb->s_root, "initial_contexts", &fsi->last_ino);
2139         if (IS_ERR(dentry)) {
2140                 ret = PTR_ERR(dentry);
2141                 goto err;
2142         }
2143
2144         ret = sel_make_initcon_files(dentry);
2145         if (ret)
2146                 goto err;
2147
2148         fsi->class_dir = sel_make_dir(sb->s_root, CLASS_DIR_NAME, &fsi->last_ino);
2149         if (IS_ERR(fsi->class_dir)) {
2150                 ret = PTR_ERR(fsi->class_dir);
2151                 fsi->class_dir = NULL;
2152                 goto err;
2153         }
2154
2155         fsi->policycap_dir = sel_make_dir(sb->s_root, POLICYCAP_DIR_NAME,
2156                                           &fsi->last_ino);
2157         if (IS_ERR(fsi->policycap_dir)) {
2158                 ret = PTR_ERR(fsi->policycap_dir);
2159                 fsi->policycap_dir = NULL;
2160                 goto err;
2161         }
2162
2163         ret = sel_make_policycap(fsi);
2164         if (ret) {
2165                 pr_err("SELinux: failed to load policy capabilities\n");
2166                 goto err;
2167         }
2168
2169         return 0;
2170 err:
2171         pr_err("SELinux: %s:  failed while creating inodes\n",
2172                 __func__);
2173
2174         selinux_fs_info_free(sb);
2175
2176         return ret;
2177 }
2178
2179 static int sel_get_tree(struct fs_context *fc)
2180 {
2181         return get_tree_single(fc, sel_fill_super);
2182 }
2183
2184 static const struct fs_context_operations sel_context_ops = {
2185         .get_tree       = sel_get_tree,
2186 };
2187
2188 static int sel_init_fs_context(struct fs_context *fc)
2189 {
2190         fc->ops = &sel_context_ops;
2191         return 0;
2192 }
2193
2194 static void sel_kill_sb(struct super_block *sb)
2195 {
2196         selinux_fs_info_free(sb);
2197         kill_litter_super(sb);
2198 }
2199
2200 static struct file_system_type sel_fs_type = {
2201         .name           = "selinuxfs",
2202         .init_fs_context = sel_init_fs_context,
2203         .kill_sb        = sel_kill_sb,
2204 };
2205
2206 static struct vfsmount *selinuxfs_mount __ro_after_init;
2207 struct path selinux_null __ro_after_init;
2208
2209 static int __init init_sel_fs(void)
2210 {
2211         struct qstr null_name = QSTR_INIT(NULL_FILE_NAME,
2212                                           sizeof(NULL_FILE_NAME)-1);
2213         int err;
2214
2215         if (!selinux_enabled_boot)
2216                 return 0;
2217
2218         err = sysfs_create_mount_point(fs_kobj, "selinux");
2219         if (err)
2220                 return err;
2221
2222         err = register_filesystem(&sel_fs_type);
2223         if (err) {
2224                 sysfs_remove_mount_point(fs_kobj, "selinux");
2225                 return err;
2226         }
2227
2228         selinux_null.mnt = selinuxfs_mount = kern_mount(&sel_fs_type);
2229         if (IS_ERR(selinuxfs_mount)) {
2230                 pr_err("selinuxfs:  could not mount!\n");
2231                 err = PTR_ERR(selinuxfs_mount);
2232                 selinuxfs_mount = NULL;
2233         }
2234         selinux_null.dentry = d_hash_and_lookup(selinux_null.mnt->mnt_root,
2235                                                 &null_name);
2236         if (IS_ERR(selinux_null.dentry)) {
2237                 pr_err("selinuxfs:  could not lookup null!\n");
2238                 err = PTR_ERR(selinux_null.dentry);
2239                 selinux_null.dentry = NULL;
2240         }
2241
2242         return err;
2243 }
2244
2245 __initcall(init_sel_fs);
2246
2247 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
2248 void exit_sel_fs(void)
2249 {
2250         sysfs_remove_mount_point(fs_kobj, "selinux");
2251         dput(selinux_null.dentry);
2252         kern_unmount(selinuxfs_mount);
2253         unregister_filesystem(&sel_fs_type);
2254 }
2255 #endif