fs/nfs/super.c

   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/addr.h>
  35 #include <linux/sunrpc/stats.h>
  36 #include <linux/sunrpc/metrics.h>
  37 #include <linux/sunrpc/xprtsock.h>
  38 #include <linux/sunrpc/xprtrdma.h>
  39 #include <linux/nfs_fs.h>
  40 #include <linux/nfs_mount.h>
  41 #include <linux/nfs4_mount.h>
  42 #include <linux/lockd/bind.h>
  43 #include <linux/seq_file.h>
  44 #include <linux/mount.h>
  45 #include <linux/namei.h>
  46 #include <linux/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <linux/slab.h>
  50 #include <net/ipv6.h>
  51 #include <linux/netdevice.h>
  52 #include <linux/nfs_xdr.h>
  53 #include <linux/magic.h>
  54 #include <linux/parser.h>
  55 #include <linux/nsproxy.h>
  56 #include <linux/rcupdate.h>
  57
  58 #include <linux/uaccess.h>
  59
  60 #include "nfs4_fs.h"
  61 #include "callback.h"
  62 #include "delegation.h"
  63 #include "iostat.h"
  64 #include "internal.h"
  65 #include "fscache.h"
  66 #include "nfs4session.h"
  67 #include "pnfs.h"
  68 #include "nfs.h"
  69
  70 #define NFSDBG_FACILITY         NFSDBG_VFS
  71 #define NFS_TEXT_DATA           1
  72
  73 #if IS_ENABLED(CONFIG_NFS_V3)
  74 #define NFS_DEFAULT_VERSION 3
  75 #else
  76 #define NFS_DEFAULT_VERSION 2
  77 #endif
  78
  79 enum {
  80         /* Mount options that take no arguments */
  81         Opt_soft, Opt_softerr, Opt_hard,
  82         Opt_posix, Opt_noposix,
  83         Opt_cto, Opt_nocto,
  84         Opt_ac, Opt_noac,
  85         Opt_lock, Opt_nolock,
  86         Opt_udp, Opt_tcp, Opt_rdma,
  87         Opt_acl, Opt_noacl,
  88         Opt_rdirplus, Opt_nordirplus,
  89         Opt_sharecache, Opt_nosharecache,
  90         Opt_resvport, Opt_noresvport,
  91         Opt_fscache, Opt_nofscache,
  92         Opt_migration, Opt_nomigration,
  93
  94         /* Mount options that take integer arguments */
  95         Opt_port,
  96         Opt_rsize, Opt_wsize, Opt_bsize,
  97         Opt_timeo, Opt_retrans,
  98         Opt_acregmin, Opt_acregmax,
  99         Opt_acdirmin, Opt_acdirmax,
 100         Opt_actimeo,
 101         Opt_namelen,
 102         Opt_mountport,
 103         Opt_mountvers,
 104         Opt_minorversion,
 105
 106         /* Mount options that take string arguments */
 107         Opt_nfsvers,
 108         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 109         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 110         Opt_lookupcache,
 111         Opt_fscache_uniq,
 112         Opt_local_lock,
 113
 114         /* Special mount options */
 115         Opt_userspace, Opt_deprecated, Opt_sloppy,
 116
 117         Opt_err
 118 };
 119
 120 static const match_table_t nfs_mount_option_tokens = {
 121         { Opt_userspace, "bg" },
 122         { Opt_userspace, "fg" },
 123         { Opt_userspace, "retry=%s" },
 124
 125         { Opt_sloppy, "sloppy" },
 126
 127         { Opt_soft, "soft" },
 128         { Opt_softerr, "softerr" },
 129         { Opt_hard, "hard" },
 130         { Opt_deprecated, "intr" },
 131         { Opt_deprecated, "nointr" },
 132         { Opt_posix, "posix" },
 133         { Opt_noposix, "noposix" },
 134         { Opt_cto, "cto" },
 135         { Opt_nocto, "nocto" },
 136         { Opt_ac, "ac" },
 137         { Opt_noac, "noac" },
 138         { Opt_lock, "lock" },
 139         { Opt_nolock, "nolock" },
 140         { Opt_udp, "udp" },
 141         { Opt_tcp, "tcp" },
 142         { Opt_rdma, "rdma" },
 143         { Opt_acl, "acl" },
 144         { Opt_noacl, "noacl" },
 145         { Opt_rdirplus, "rdirplus" },
 146         { Opt_nordirplus, "nordirplus" },
 147         { Opt_sharecache, "sharecache" },
 148         { Opt_nosharecache, "nosharecache" },
 149         { Opt_resvport, "resvport" },
 150         { Opt_noresvport, "noresvport" },
 151         { Opt_fscache, "fsc" },
 152         { Opt_nofscache, "nofsc" },
 153         { Opt_migration, "migration" },
 154         { Opt_nomigration, "nomigration" },
 155
 156         { Opt_port, "port=%s" },
 157         { Opt_rsize, "rsize=%s" },
 158         { Opt_wsize, "wsize=%s" },
 159         { Opt_bsize, "bsize=%s" },
 160         { Opt_timeo, "timeo=%s" },
 161         { Opt_retrans, "retrans=%s" },
 162         { Opt_acregmin, "acregmin=%s" },
 163         { Opt_acregmax, "acregmax=%s" },
 164         { Opt_acdirmin, "acdirmin=%s" },
 165         { Opt_acdirmax, "acdirmax=%s" },
 166         { Opt_actimeo, "actimeo=%s" },
 167         { Opt_namelen, "namlen=%s" },
 168         { Opt_mountport, "mountport=%s" },
 169         { Opt_mountvers, "mountvers=%s" },
 170         { Opt_minorversion, "minorversion=%s" },
 171
 172         { Opt_nfsvers, "nfsvers=%s" },
 173         { Opt_nfsvers, "vers=%s" },
 174
 175         { Opt_sec, "sec=%s" },
 176         { Opt_proto, "proto=%s" },
 177         { Opt_mountproto, "mountproto=%s" },
 178         { Opt_addr, "addr=%s" },
 179         { Opt_clientaddr, "clientaddr=%s" },
 180         { Opt_mounthost, "mounthost=%s" },
 181         { Opt_mountaddr, "mountaddr=%s" },
 182
 183         { Opt_lookupcache, "lookupcache=%s" },
 184         { Opt_fscache_uniq, "fsc=%s" },
 185         { Opt_local_lock, "local_lock=%s" },
 186
 187         /* The following needs to be listed after all other options */
 188         { Opt_nfsvers, "v%s" },
 189
 190         { Opt_err, NULL }
 191 };
 192
 193 enum {
 194         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 195         Opt_xprt_rdma6,
 196
 197         Opt_xprt_err
 198 };
 199
 200 static const match_table_t nfs_xprt_protocol_tokens = {
 201         { Opt_xprt_udp, "udp" },
 202         { Opt_xprt_udp6, "udp6" },
 203         { Opt_xprt_tcp, "tcp" },
 204         { Opt_xprt_tcp6, "tcp6" },
 205         { Opt_xprt_rdma, "rdma" },
 206         { Opt_xprt_rdma6, "rdma6" },
 207
 208         { Opt_xprt_err, NULL }
 209 };
 210
 211 enum {
 212         Opt_sec_none, Opt_sec_sys,
 213         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 214         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 215         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 216
 217         Opt_sec_err
 218 };
 219
 220 static const match_table_t nfs_secflavor_tokens = {
 221         { Opt_sec_none, "none" },
 222         { Opt_sec_none, "null" },
 223         { Opt_sec_sys, "sys" },
 224
 225         { Opt_sec_krb5, "krb5" },
 226         { Opt_sec_krb5i, "krb5i" },
 227         { Opt_sec_krb5p, "krb5p" },
 228
 229         { Opt_sec_lkey, "lkey" },
 230         { Opt_sec_lkeyi, "lkeyi" },
 231         { Opt_sec_lkeyp, "lkeyp" },
 232
 233         { Opt_sec_spkm, "spkm3" },
 234         { Opt_sec_spkmi, "spkm3i" },
 235         { Opt_sec_spkmp, "spkm3p" },
 236
 237         { Opt_sec_err, NULL }
 238 };
 239
 240 enum {
 241         Opt_lookupcache_all, Opt_lookupcache_positive,
 242         Opt_lookupcache_none,
 243
 244         Opt_lookupcache_err
 245 };
 246
 247 static match_table_t nfs_lookupcache_tokens = {
 248         { Opt_lookupcache_all, "all" },
 249         { Opt_lookupcache_positive, "pos" },
 250         { Opt_lookupcache_positive, "positive" },
 251         { Opt_lookupcache_none, "none" },
 252
 253         { Opt_lookupcache_err, NULL }
 254 };
 255
 256 enum {
 257         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 258         Opt_local_lock_none,
 259
 260         Opt_local_lock_err
 261 };
 262
 263 static match_table_t nfs_local_lock_tokens = {
 264         { Opt_local_lock_all, "all" },
 265         { Opt_local_lock_flock, "flock" },
 266         { Opt_local_lock_posix, "posix" },
 267         { Opt_local_lock_none, "none" },
 268
 269         { Opt_local_lock_err, NULL }
 270 };
 271
 272 enum {
 273         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 274         Opt_vers_4_1, Opt_vers_4_2,
 275
 276         Opt_vers_err
 277 };
 278
 279 static match_table_t nfs_vers_tokens = {
 280         { Opt_vers_2, "2" },
 281         { Opt_vers_3, "3" },
 282         { Opt_vers_4, "4" },
 283         { Opt_vers_4_0, "4.0" },
 284         { Opt_vers_4_1, "4.1" },
 285         { Opt_vers_4_2, "4.2" },
 286
 287         { Opt_vers_err, NULL }
 288 };
 289
 290 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 291                 int flags, const char *dev_name, void *raw_data);
 292
 293 struct file_system_type nfs_fs_type = {
 294         .owner          = THIS_MODULE,
 295         .name           = "nfs",
 296         .mount          = nfs_fs_mount,
 297         .kill_sb        = nfs_kill_super,
 298         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 299 };
 300 MODULE_ALIAS_FS("nfs");
 301 EXPORT_SYMBOL_GPL(nfs_fs_type);
 302
 303 struct file_system_type nfs_xdev_fs_type = {
 304         .owner          = THIS_MODULE,
 305         .name           = "nfs",
 306         .mount          = nfs_xdev_mount,
 307         .kill_sb        = nfs_kill_super,
 308         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 309 };
 310
 311 const struct super_operations nfs_sops = {
 312         .alloc_inode    = nfs_alloc_inode,
 313         .free_inode     = nfs_free_inode,
 314         .write_inode    = nfs_write_inode,
 315         .drop_inode     = nfs_drop_inode,
 316         .statfs         = nfs_statfs,
 317         .evict_inode    = nfs_evict_inode,
 318         .umount_begin   = nfs_umount_begin,
 319         .show_options   = nfs_show_options,
 320         .show_devname   = nfs_show_devname,
 321         .show_path      = nfs_show_path,
 322         .show_stats     = nfs_show_stats,
 323         .remount_fs     = nfs_remount,
 324 };
 325 EXPORT_SYMBOL_GPL(nfs_sops);
 326
 327 #if IS_ENABLED(CONFIG_NFS_V4)
 328 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 329 static int nfs4_validate_mount_data(void *options,
 330         struct nfs_parsed_mount_data *args, const char *dev_name);
 331
 332 struct file_system_type nfs4_fs_type = {
 333         .owner          = THIS_MODULE,
 334         .name           = "nfs4",
 335         .mount          = nfs_fs_mount,
 336         .kill_sb        = nfs_kill_super,
 337         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 338 };
 339 MODULE_ALIAS_FS("nfs4");
 340 MODULE_ALIAS("nfs4");
 341 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 342
 343 static int __init register_nfs4_fs(void)
 344 {
 345         return register_filesystem(&nfs4_fs_type);
 346 }
 347
 348 static void unregister_nfs4_fs(void)
 349 {
 350         unregister_filesystem(&nfs4_fs_type);
 351 }
 352 #else
 353 static int __init register_nfs4_fs(void)
 354 {
 355         return 0;
 356 }
 357
 358 static void unregister_nfs4_fs(void)
 359 {
 360 }
 361 #endif
 362
 363 static struct shrinker acl_shrinker = {
 364         .count_objects  = nfs_access_cache_count,
 365         .scan_objects   = nfs_access_cache_scan,
 366         .seeks          = DEFAULT_SEEKS,
 367 };
 368
 369 /*
 370  * Register the NFS filesystems
 371  */
 372 int __init register_nfs_fs(void)
 373 {
 374         int ret;
 375
 376         ret = register_filesystem(&nfs_fs_type);
 377         if (ret < 0)
 378                 goto error_0;
 379
 380         ret = register_nfs4_fs();
 381         if (ret < 0)
 382                 goto error_1;
 383
 384         ret = nfs_register_sysctl();
 385         if (ret < 0)
 386                 goto error_2;
 387         ret = register_shrinker(&acl_shrinker);
 388         if (ret < 0)
 389                 goto error_3;
 390         return 0;
 391 error_3:
 392         nfs_unregister_sysctl();
 393 error_2:
 394         unregister_nfs4_fs();
 395 error_1:
 396         unregister_filesystem(&nfs_fs_type);
 397 error_0:
 398         return ret;
 399 }
 400
 401 /*
 402  * Unregister the NFS filesystems
 403  */
 404 void __exit unregister_nfs_fs(void)
 405 {
 406         unregister_shrinker(&acl_shrinker);
 407         nfs_unregister_sysctl();
 408         unregister_nfs4_fs();
 409         unregister_filesystem(&nfs_fs_type);
 410 }
 411
 412 bool nfs_sb_active(struct super_block *sb)
 413 {
 414         struct nfs_server *server = NFS_SB(sb);
 415
 416         if (!atomic_inc_not_zero(&sb->s_active))
 417                 return false;
 418         if (atomic_inc_return(&server->active) != 1)
 419                 atomic_dec(&sb->s_active);
 420         return true;
 421 }
 422 EXPORT_SYMBOL_GPL(nfs_sb_active);
 423
 424 void nfs_sb_deactive(struct super_block *sb)
 425 {
 426         struct nfs_server *server = NFS_SB(sb);
 427
 428         if (atomic_dec_and_test(&server->active))
 429                 deactivate_super(sb);
 430 }
 431 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 432
 433 /*
 434  * Deliver file system statistics to userspace
 435  */
 436 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 437 {
 438         struct nfs_server *server = NFS_SB(dentry->d_sb);
 439         unsigned char blockbits;
 440         unsigned long blockres;
 441         struct nfs_fh *fh = NFS_FH(d_inode(dentry));
 442         struct nfs_fsstat res;
 443         int error = -ENOMEM;
 444
 445         res.fattr = nfs_alloc_fattr();
 446         if (res.fattr == NULL)
 447                 goto out_err;
 448
 449         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 450         if (unlikely(error == -ESTALE)) {
 451                 struct dentry *pd_dentry;
 452
 453                 pd_dentry = dget_parent(dentry);
 454                 if (pd_dentry != NULL) {
 455                         nfs_zap_caches(d_inode(pd_dentry));
 456                         dput(pd_dentry);
 457                 }
 458         }
 459         nfs_free_fattr(res.fattr);
 460         if (error < 0)
 461                 goto out_err;
 462
 463         buf->f_type = NFS_SUPER_MAGIC;
 464
 465         /*
 466          * Current versions of glibc do not correctly handle the
 467          * case where f_frsize != f_bsize.  Eventually we want to
 468          * report the value of wtmult in this field.
 469          */
 470         buf->f_frsize = dentry->d_sb->s_blocksize;
 471
 472         /*
 473          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 474          * are reported in units of f_frsize.  Linux hasn't had
 475          * an f_frsize field in its statfs struct until recently,
 476          * thus historically Linux's sys_statfs reports these
 477          * fields in units of f_bsize.
 478          */
 479         buf->f_bsize = dentry->d_sb->s_blocksize;
 480         blockbits = dentry->d_sb->s_blocksize_bits;
 481         blockres = (1 << blockbits) - 1;
 482         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 483         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 484         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 485
 486         buf->f_files = res.tfiles;
 487         buf->f_ffree = res.afiles;
 488
 489         buf->f_namelen = server->namelen;
 490
 491         return 0;
 492
 493  out_err:
 494         dprintk("%s: statfs error = %d\n", __func__, -error);
 495         return error;
 496 }
 497 EXPORT_SYMBOL_GPL(nfs_statfs);
 498
 499 /*
 500  * Map the security flavour number to a name
 501  */
 502 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 503 {
 504         static const struct {
 505                 rpc_authflavor_t flavour;
 506                 const char *str;
 507         } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
 508                 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
 509                 { RPC_AUTH_NULL, "null" },
 510                 { RPC_AUTH_UNIX, "sys" },
 511                 { RPC_AUTH_GSS_KRB5, "krb5" },
 512                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 513                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 514                 { RPC_AUTH_GSS_LKEY, "lkey" },
 515                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 516                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 517                 { RPC_AUTH_GSS_SPKM, "spkm" },
 518                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 519                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 520                 { UINT_MAX, "unknown" }
 521         };
 522         int i;
 523
 524         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 525                 if (sec_flavours[i].flavour == flavour)
 526                         break;
 527         }
 528         return sec_flavours[i].str;
 529 }
 530
 531 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 532                                   int showdefaults)
 533 {
 534         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 535         char *proto = NULL;
 536
 537         switch (sap->sa_family) {
 538         case AF_INET:
 539                 switch (nfss->mountd_protocol) {
 540                 case IPPROTO_UDP:
 541                         proto = RPCBIND_NETID_UDP;
 542                         break;
 543                 case IPPROTO_TCP:
 544                         proto = RPCBIND_NETID_TCP;
 545                         break;
 546                 }
 547                 break;
 548         case AF_INET6:
 549                 switch (nfss->mountd_protocol) {
 550                 case IPPROTO_UDP:
 551                         proto = RPCBIND_NETID_UDP6;
 552                         break;
 553                 case IPPROTO_TCP:
 554                         proto = RPCBIND_NETID_TCP6;
 555                         break;
 556                 }
 557                 break;
 558         }
 559         if (proto || showdefaults)
 560                 seq_printf(m, ",mountproto=%s", proto ?: "auto");
 561 }
 562
 563 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 564                                     int showdefaults)
 565 {
 566         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 567
 568         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 569                 return;
 570
 571         switch (sap->sa_family) {
 572         case AF_INET: {
 573                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 574                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 575                 break;
 576         }
 577         case AF_INET6: {
 578                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 579                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 580                 break;
 581         }
 582         default:
 583                 if (showdefaults)
 584                         seq_printf(m, ",mountaddr=unspecified");
 585         }
 586
 587         if (nfss->mountd_version || showdefaults)
 588                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 589         if ((nfss->mountd_port &&
 590                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 591                 showdefaults)
 592                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 593
 594         nfs_show_mountd_netid(m, nfss, showdefaults);
 595 }
 596
 597 #if IS_ENABLED(CONFIG_NFS_V4)
 598 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 599                                     int showdefaults)
 600 {
 601         struct nfs_client *clp = nfss->nfs_client;
 602
 603         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 604 }
 605 #else
 606 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 607                                     int showdefaults)
 608 {
 609 }
 610 #endif
 611
 612 static void nfs_show_nfs_version(struct seq_file *m,
 613                 unsigned int version,
 614                 unsigned int minorversion)
 615 {
 616         seq_printf(m, ",vers=%u", version);
 617         if (version == 4)
 618                 seq_printf(m, ".%u", minorversion);
 619 }
 620
 621 /*
 622  * Describe the mount options in force on this server representation
 623  */
 624 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 625                                    int showdefaults)
 626 {
 627         static const struct proc_nfs_info {
 628                 int flag;
 629                 const char *str;
 630                 const char *nostr;
 631         } nfs_info[] = {
 632                 { NFS_MOUNT_SOFT, ",soft", "" },
 633                 { NFS_MOUNT_SOFTERR, ",softerr", "" },
 634                 { NFS_MOUNT_POSIX, ",posix", "" },
 635                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 636                 { NFS_MOUNT_NOAC, ",noac", "" },
 637                 { NFS_MOUNT_NONLM, ",nolock", "" },
 638                 { NFS_MOUNT_NOACL, ",noacl", "" },
 639                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 640                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 641                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 642                 { 0, NULL, NULL }
 643         };
 644         const struct proc_nfs_info *nfs_infop;
 645         struct nfs_client *clp = nfss->nfs_client;
 646         u32 version = clp->rpc_ops->version;
 647         int local_flock, local_fcntl;
 648
 649         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 650         seq_printf(m, ",rsize=%u", nfss->rsize);
 651         seq_printf(m, ",wsize=%u", nfss->wsize);
 652         if (nfss->bsize != 0)
 653                 seq_printf(m, ",bsize=%u", nfss->bsize);
 654         seq_printf(m, ",namlen=%u", nfss->namelen);
 655         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 656                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 657         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 658                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 659         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 660                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 661         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 662                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 663         if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR)))
 664                         seq_puts(m, ",hard");
 665         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 666                 if (nfss->flags & nfs_infop->flag)
 667                         seq_puts(m, nfs_infop->str);
 668                 else
 669                         seq_puts(m, nfs_infop->nostr);
 670         }
 671         rcu_read_lock();
 672         seq_printf(m, ",proto=%s",
 673                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 674         rcu_read_unlock();
 675         if (version == 4) {
 676                 if (nfss->port != NFS_PORT)
 677                         seq_printf(m, ",port=%u", nfss->port);
 678         } else
 679                 if (nfss->port)
 680                         seq_printf(m, ",port=%u", nfss->port);
 681
 682         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 683         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 684         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 685
 686         if (version != 4)
 687                 nfs_show_mountd_options(m, nfss, showdefaults);
 688         else
 689                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 690
 691         if (nfss->options & NFS_OPTION_FSCACHE)
 692                 seq_printf(m, ",fsc");
 693
 694         if (nfss->options & NFS_OPTION_MIGRATION)
 695                 seq_printf(m, ",migration");
 696
 697         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 698                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 699                         seq_printf(m, ",lookupcache=none");
 700                 else
 701                         seq_printf(m, ",lookupcache=pos");
 702         }
 703
 704         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 705         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 706
 707         if (!local_flock && !local_fcntl)
 708                 seq_printf(m, ",local_lock=none");
 709         else if (local_flock && local_fcntl)
 710                 seq_printf(m, ",local_lock=all");
 711         else if (local_flock)
 712                 seq_printf(m, ",local_lock=flock");
 713         else
 714                 seq_printf(m, ",local_lock=posix");
 715 }
 716
 717 /*
 718  * Describe the mount options on this VFS mountpoint
 719  */
 720 int nfs_show_options(struct seq_file *m, struct dentry *root)
 721 {
 722         struct nfs_server *nfss = NFS_SB(root->d_sb);
 723
 724         nfs_show_mount_options(m, nfss, 0);
 725
 726         rcu_read_lock();
 727         seq_printf(m, ",addr=%s",
 728                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 729                                                         RPC_DISPLAY_ADDR));
 730         rcu_read_unlock();
 731
 732         return 0;
 733 }
 734 EXPORT_SYMBOL_GPL(nfs_show_options);
 735
 736 #if IS_ENABLED(CONFIG_NFS_V4)
 737 #ifdef CONFIG_NFS_V4_1
 738 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 739 {
 740         if (nfs4_has_session(server->nfs_client))
 741                 seq_printf(m, ",sessions");
 742 }
 743 #else
 744 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 745 #endif
 746 #endif
 747
 748 #ifdef CONFIG_NFS_V4_1
 749 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 750 {
 751         seq_printf(m, ",pnfs=");
 752         if (server->pnfs_curr_ld)
 753                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 754         else
 755                 seq_printf(m, "not configured");
 756 }
 757
 758 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 759 {
 760         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 761                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 762                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 763                            "date='%llu,%u'",
 764                            impl_id->name, impl_id->domain,
 765                            impl_id->date.seconds, impl_id->date.nseconds);
 766         }
 767 }
 768 #else
 769 #if IS_ENABLED(CONFIG_NFS_V4)
 770 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 771 {
 772 }
 773 #endif
 774 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 775 {
 776 }
 777 #endif
 778
 779 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 780 {
 781         char *page = (char *) __get_free_page(GFP_KERNEL);
 782         char *devname, *dummy;
 783         int err = 0;
 784         if (!page)
 785                 return -ENOMEM;
 786         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 787         if (IS_ERR(devname))
 788                 err = PTR_ERR(devname);
 789         else
 790                 seq_escape(m, devname, " \t\n\\");
 791         free_page((unsigned long)page);
 792         return err;
 793 }
 794 EXPORT_SYMBOL_GPL(nfs_show_devname);
 795
 796 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 797 {
 798         seq_puts(m, "/");
 799         return 0;
 800 }
 801 EXPORT_SYMBOL_GPL(nfs_show_path);
 802
 803 /*
 804  * Present statistical information for this VFS mountpoint
 805  */
 806 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 807 {
 808         int i, cpu;
 809         struct nfs_server *nfss = NFS_SB(root->d_sb);
 810         struct rpc_auth *auth = nfss->client->cl_auth;
 811         struct nfs_iostats totals = { };
 812
 813         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 814
 815         /*
 816          * Display all mount option settings
 817          */
 818         seq_printf(m, "\n\topts:\t");
 819         seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw");
 820         seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : "");
 821         seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : "");
 822         seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : "");
 823         nfs_show_mount_options(m, nfss, 1);
 824
 825         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 826
 827         show_implementation_id(m, nfss);
 828
 829         seq_printf(m, "\n\tcaps:\t");
 830         seq_printf(m, "caps=0x%x", nfss->caps);
 831         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 832         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 833         seq_printf(m, ",bsize=%u", nfss->bsize);
 834         seq_printf(m, ",namlen=%u", nfss->namelen);
 835
 836 #if IS_ENABLED(CONFIG_NFS_V4)
 837         if (nfss->nfs_client->rpc_ops->version == 4) {
 838                 seq_printf(m, "\n\tnfsv4:\t");
 839                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 840                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 841                 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
 842                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 843                 show_sessions(m, nfss);
 844                 show_pnfs(m, nfss);
 845         }
 846 #endif
 847
 848         /*
 849          * Display security flavor in effect for this mount
 850          */
 851         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 852         if (auth->au_flavor)
 853                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 854
 855         /*
 856          * Display superblock I/O counters
 857          */
 858         for_each_possible_cpu(cpu) {
 859                 struct nfs_iostats *stats;
 860
 861                 preempt_disable();
 862                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 863
 864                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 865                         totals.events[i] += stats->events[i];
 866                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 867                         totals.bytes[i] += stats->bytes[i];
 868 #ifdef CONFIG_NFS_FSCACHE
 869                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 870                         totals.fscache[i] += stats->fscache[i];
 871 #endif
 872
 873                 preempt_enable();
 874         }
 875
 876         seq_printf(m, "\n\tevents:\t");
 877         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 878                 seq_printf(m, "%lu ", totals.events[i]);
 879         seq_printf(m, "\n\tbytes:\t");
 880         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 881                 seq_printf(m, "%Lu ", totals.bytes[i]);
 882 #ifdef CONFIG_NFS_FSCACHE
 883         if (nfss->options & NFS_OPTION_FSCACHE) {
 884                 seq_printf(m, "\n\tfsc:\t");
 885                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 886                         seq_printf(m, "%Lu ", totals.fscache[i]);
 887         }
 888 #endif
 889         seq_printf(m, "\n");
 890
 891         rpc_clnt_show_stats(m, nfss->client);
 892
 893         return 0;
 894 }
 895 EXPORT_SYMBOL_GPL(nfs_show_stats);
 896
 897 /*
 898  * Begin unmount by attempting to remove all automounted mountpoints we added
 899  * in response to xdev traversals and referrals
 900  */
 901 void nfs_umount_begin(struct super_block *sb)
 902 {
 903         struct nfs_server *server;
 904         struct rpc_clnt *rpc;
 905
 906         server = NFS_SB(sb);
 907         /* -EIO all pending I/O */
 908         rpc = server->client_acl;
 909         if (!IS_ERR(rpc))
 910                 rpc_killall_tasks(rpc);
 911         rpc = server->client;
 912         if (!IS_ERR(rpc))
 913                 rpc_killall_tasks(rpc);
 914 }
 915 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 916
 917 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 918 {
 919         struct nfs_parsed_mount_data *data;
 920
 921         data = kzalloc(sizeof(*data), GFP_KERNEL);
 922         if (data) {
 923                 data->timeo             = NFS_UNSPEC_TIMEO;
 924                 data->retrans           = NFS_UNSPEC_RETRANS;
 925                 data->acregmin          = NFS_DEF_ACREGMIN;
 926                 data->acregmax          = NFS_DEF_ACREGMAX;
 927                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 928                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 929                 data->mount_server.port = NFS_UNSPEC_PORT;
 930                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 931                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 932                 data->selected_flavor   = RPC_AUTH_MAXFLAVOR;
 933                 data->minorversion      = 0;
 934                 data->need_mount        = true;
 935                 data->net               = current->nsproxy->net_ns;
 936                 data->lsm_opts          = NULL;
 937         }
 938         return data;
 939 }
 940
 941 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 942 {
 943         if (data) {
 944                 kfree(data->client_address);
 945                 kfree(data->mount_server.hostname);
 946                 kfree(data->nfs_server.export_path);
 947                 kfree(data->nfs_server.hostname);
 948                 kfree(data->fscache_uniq);
 949                 security_free_mnt_opts(&data->lsm_opts);
 950                 kfree(data);
 951         }
 952 }
 953
 954 /*
 955  * Sanity-check a server address provided by the mount command.
 956  *
 957  * Address family must be initialized, and address must not be
 958  * the ANY address for that family.
 959  */
 960 static int nfs_verify_server_address(struct sockaddr *addr)
 961 {
 962         switch (addr->sa_family) {
 963         case AF_INET: {
 964                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 965                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 966         }
 967         case AF_INET6: {
 968                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 969                 return !ipv6_addr_any(sa);
 970         }
 971         }
 972
 973         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 974         return 0;
 975 }
 976
 977 /*
 978  * Select between a default port value and a user-specified port value.
 979  * If a zero value is set, then autobind will be used.
 980  */
 981 static void nfs_set_port(struct sockaddr *sap, int *port,
 982                                  const unsigned short default_port)
 983 {
 984         if (*port == NFS_UNSPEC_PORT)
 985                 *port = default_port;
 986
 987         rpc_set_port(sap, *port);
 988 }
 989
 990 /*
 991  * Sanity check the NFS transport protocol.
 992  *
 993  */
 994 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 995 {
 996         switch (mnt->nfs_server.protocol) {
 997         case XPRT_TRANSPORT_UDP:
 998         case XPRT_TRANSPORT_TCP:
 999         case XPRT_TRANSPORT_RDMA:
1000                 break;
1001         default:
1002                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1003         }
1004 }
1005
1006 /*
1007  * For text based NFSv2/v3 mounts, the mount protocol transport default
1008  * settings should depend upon the specified NFS transport.
1009  */
1010 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1011 {
1012         nfs_validate_transport_protocol(mnt);
1013
1014         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1015             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1016                         return;
1017         switch (mnt->nfs_server.protocol) {
1018         case XPRT_TRANSPORT_UDP:
1019                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1020                 break;
1021         case XPRT_TRANSPORT_TCP:
1022         case XPRT_TRANSPORT_RDMA:
1023                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1024         }
1025 }
1026
1027 /*
1028  * Add 'flavor' to 'auth_info' if not already present.
1029  * Returns true if 'flavor' ends up in the list, false otherwise
1030  */
1031 static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
1032                               rpc_authflavor_t flavor)
1033 {
1034         unsigned int i;
1035         unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
1036
1037         /* make sure this flavor isn't already in the list */
1038         for (i = 0; i < auth_info->flavor_len; i++) {
1039                 if (flavor == auth_info->flavors[i])
1040                         return true;
1041         }
1042
1043         if (auth_info->flavor_len + 1 >= max_flavor_len) {
1044                 dfprintk(MOUNT, "NFS: too many sec= flavors\n");
1045                 return false;
1046         }
1047
1048         auth_info->flavors[auth_info->flavor_len++] = flavor;
1049         return true;
1050 }
1051
1052 /*
1053  * Return true if 'match' is in auth_info or auth_info is empty.
1054  * Return false otherwise.
1055  */
1056 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
1057                          rpc_authflavor_t match)
1058 {
1059         int i;
1060
1061         if (!auth_info->flavor_len)
1062                 return true;
1063
1064         for (i = 0; i < auth_info->flavor_len; i++) {
1065                 if (auth_info->flavors[i] == match)
1066                         return true;
1067         }
1068         return false;
1069 }
1070 EXPORT_SYMBOL_GPL(nfs_auth_info_match);
1071
1072 /*
1073  * Parse the value of the 'sec=' option.
1074  */
1075 static int nfs_parse_security_flavors(char *value,
1076                                       struct nfs_parsed_mount_data *mnt)
1077 {
1078         substring_t args[MAX_OPT_ARGS];
1079         rpc_authflavor_t pseudoflavor;
1080         char *p;
1081
1082         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1083
1084         while ((p = strsep(&value, ":")) != NULL) {
1085                 switch (match_token(p, nfs_secflavor_tokens, args)) {
1086                 case Opt_sec_none:
1087                         pseudoflavor = RPC_AUTH_NULL;
1088                         break;
1089                 case Opt_sec_sys:
1090                         pseudoflavor = RPC_AUTH_UNIX;
1091                         break;
1092                 case Opt_sec_krb5:
1093                         pseudoflavor = RPC_AUTH_GSS_KRB5;
1094                         break;
1095                 case Opt_sec_krb5i:
1096                         pseudoflavor = RPC_AUTH_GSS_KRB5I;
1097                         break;
1098                 case Opt_sec_krb5p:
1099                         pseudoflavor = RPC_AUTH_GSS_KRB5P;
1100                         break;
1101                 case Opt_sec_lkey:
1102                         pseudoflavor = RPC_AUTH_GSS_LKEY;
1103                         break;
1104                 case Opt_sec_lkeyi:
1105                         pseudoflavor = RPC_AUTH_GSS_LKEYI;
1106                         break;
1107                 case Opt_sec_lkeyp:
1108                         pseudoflavor = RPC_AUTH_GSS_LKEYP;
1109                         break;
1110                 case Opt_sec_spkm:
1111                         pseudoflavor = RPC_AUTH_GSS_SPKM;
1112                         break;
1113                 case Opt_sec_spkmi:
1114                         pseudoflavor = RPC_AUTH_GSS_SPKMI;
1115                         break;
1116                 case Opt_sec_spkmp:
1117                         pseudoflavor = RPC_AUTH_GSS_SPKMP;
1118                         break;
1119                 default:
1120                         dfprintk(MOUNT,
1121                                  "NFS: sec= option '%s' not recognized\n", p);
1122                         return 0;
1123                 }
1124
1125                 if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
1126                         return 0;
1127         }
1128
1129         return 1;
1130 }
1131
1132 static int nfs_parse_version_string(char *string,
1133                 struct nfs_parsed_mount_data *mnt,
1134                 substring_t *args)
1135 {
1136         mnt->flags &= ~NFS_MOUNT_VER3;
1137         switch (match_token(string, nfs_vers_tokens, args)) {
1138         case Opt_vers_2:
1139                 mnt->version = 2;
1140                 break;
1141         case Opt_vers_3:
1142                 mnt->flags |= NFS_MOUNT_VER3;
1143                 mnt->version = 3;
1144                 break;
1145         case Opt_vers_4:
1146                 /* Backward compatibility option. In future,
1147                  * the mount program should always supply
1148                  * a NFSv4 minor version number.
1149                  */
1150                 mnt->version = 4;
1151                 break;
1152         case Opt_vers_4_0:
1153                 mnt->version = 4;
1154                 mnt->minorversion = 0;
1155                 break;
1156         case Opt_vers_4_1:
1157                 mnt->version = 4;
1158                 mnt->minorversion = 1;
1159                 break;
1160         case Opt_vers_4_2:
1161                 mnt->version = 4;
1162                 mnt->minorversion = 2;
1163                 break;
1164         default:
1165                 return 0;
1166         }
1167         return 1;
1168 }
1169
1170 static int nfs_get_option_str(substring_t args[], char **option)
1171 {
1172         kfree(*option);
1173         *option = match_strdup(args);
1174         return !*option;
1175 }
1176
1177 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1178 {
1179         int rc;
1180         char *string;
1181
1182         string = match_strdup(args);
1183         if (string == NULL)
1184                 return -ENOMEM;
1185         rc = kstrtoul(string, 10, option);
1186         kfree(string);
1187
1188         return rc;
1189 }
1190
1191 static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
1192                 unsigned long l_bound, unsigned long u_bound)
1193 {
1194         int ret;
1195
1196         ret = nfs_get_option_ul(args, option);
1197         if (ret != 0)
1198                 return ret;
1199         if (*option < l_bound || *option > u_bound)
1200                 return -ERANGE;
1201         return 0;
1202 }
1203
1204 /*
1205  * Error-check and convert a string of mount options from user space into
1206  * a data structure.  The whole mount string is processed; bad options are
1207  * skipped as they are encountered.  If there were no errors, return 1;
1208  * otherwise return 0 (zero).
1209  */
1210 static int nfs_parse_mount_options(char *raw,
1211                                    struct nfs_parsed_mount_data *mnt)
1212 {
1213         char *p, *string;
1214         int rc, sloppy = 0, invalid_option = 0;
1215         unsigned short protofamily = AF_UNSPEC;
1216         unsigned short mountfamily = AF_UNSPEC;
1217
1218         if (!raw) {
1219                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1220                 return 1;
1221         }
1222         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1223
1224         rc = security_sb_eat_lsm_opts(raw, &mnt->lsm_opts);
1225         if (rc)
1226                 goto out_security_failure;
1227
1228         while ((p = strsep(&raw, ",")) != NULL) {
1229                 substring_t args[MAX_OPT_ARGS];
1230                 unsigned long option;
1231                 int token;
1232
1233                 if (!*p)
1234                         continue;
1235
1236                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1237
1238                 token = match_token(p, nfs_mount_option_tokens, args);
1239                 switch (token) {
1240
1241                 /*
1242                  * boolean options:  foo/nofoo
1243                  */
1244                 case Opt_soft:
1245                         mnt->flags |= NFS_MOUNT_SOFT;
1246                         mnt->flags &= ~NFS_MOUNT_SOFTERR;
1247                         break;
1248                 case Opt_softerr:
1249                         mnt->flags |= NFS_MOUNT_SOFTERR;
1250                         mnt->flags &= ~NFS_MOUNT_SOFT;
1251                         break;
1252                 case Opt_hard:
1253                         mnt->flags &= ~(NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR);
1254                         break;
1255                 case Opt_posix:
1256                         mnt->flags |= NFS_MOUNT_POSIX;
1257                         break;
1258                 case Opt_noposix:
1259                         mnt->flags &= ~NFS_MOUNT_POSIX;
1260                         break;
1261                 case Opt_cto:
1262                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1263                         break;
1264                 case Opt_nocto:
1265                         mnt->flags |= NFS_MOUNT_NOCTO;
1266                         break;
1267                 case Opt_ac:
1268                         mnt->flags &= ~NFS_MOUNT_NOAC;
1269                         break;
1270                 case Opt_noac:
1271                         mnt->flags |= NFS_MOUNT_NOAC;
1272                         break;
1273                 case Opt_lock:
1274                         mnt->flags &= ~NFS_MOUNT_NONLM;
1275                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1276                                         NFS_MOUNT_LOCAL_FCNTL);
1277                         break;
1278                 case Opt_nolock:
1279                         mnt->flags |= NFS_MOUNT_NONLM;
1280                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1281                                        NFS_MOUNT_LOCAL_FCNTL);
1282                         break;
1283                 case Opt_udp:
1284                         mnt->flags &= ~NFS_MOUNT_TCP;
1285                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1286                         break;
1287                 case Opt_tcp:
1288                         mnt->flags |= NFS_MOUNT_TCP;
1289                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1290                         break;
1291                 case Opt_rdma:
1292                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1293                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1294                         xprt_load_transport(p);
1295                         break;
1296                 case Opt_acl:
1297                         mnt->flags &= ~NFS_MOUNT_NOACL;
1298                         break;
1299                 case Opt_noacl:
1300                         mnt->flags |= NFS_MOUNT_NOACL;
1301                         break;
1302                 case Opt_rdirplus:
1303                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1304                         break;
1305                 case Opt_nordirplus:
1306                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1307                         break;
1308                 case Opt_sharecache:
1309                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1310                         break;
1311                 case Opt_nosharecache:
1312                         mnt->flags |= NFS_MOUNT_UNSHARED;
1313                         break;
1314                 case Opt_resvport:
1315                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1316                         break;
1317                 case Opt_noresvport:
1318                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1319                         break;
1320                 case Opt_fscache:
1321                         mnt->options |= NFS_OPTION_FSCACHE;
1322                         kfree(mnt->fscache_uniq);
1323                         mnt->fscache_uniq = NULL;
1324                         break;
1325                 case Opt_nofscache:
1326                         mnt->options &= ~NFS_OPTION_FSCACHE;
1327                         kfree(mnt->fscache_uniq);
1328                         mnt->fscache_uniq = NULL;
1329                         break;
1330                 case Opt_migration:
1331                         mnt->options |= NFS_OPTION_MIGRATION;
1332                         break;
1333                 case Opt_nomigration:
1334                         mnt->options &= ~NFS_OPTION_MIGRATION;
1335                         break;
1336
1337                 /*
1338                  * options that take numeric values
1339                  */
1340                 case Opt_port:
1341                         if (nfs_get_option_ul(args, &option) ||
1342                             option > USHRT_MAX)
1343                                 goto out_invalid_value;
1344                         mnt->nfs_server.port = option;
1345                         break;
1346                 case Opt_rsize:
1347                         if (nfs_get_option_ul(args, &option))
1348                                 goto out_invalid_value;
1349                         mnt->rsize = option;
1350                         break;
1351                 case Opt_wsize:
1352                         if (nfs_get_option_ul(args, &option))
1353                                 goto out_invalid_value;
1354                         mnt->wsize = option;
1355                         break;
1356                 case Opt_bsize:
1357                         if (nfs_get_option_ul(args, &option))
1358                                 goto out_invalid_value;
1359                         mnt->bsize = option;
1360                         break;
1361                 case Opt_timeo:
1362                         if (nfs_get_option_ul_bound(args, &option, 1, INT_MAX))
1363                                 goto out_invalid_value;
1364                         mnt->timeo = option;
1365                         break;
1366                 case Opt_retrans:
1367                         if (nfs_get_option_ul_bound(args, &option, 0, INT_MAX))
1368                                 goto out_invalid_value;
1369                         mnt->retrans = option;
1370                         break;
1371                 case Opt_acregmin:
1372                         if (nfs_get_option_ul(args, &option))
1373                                 goto out_invalid_value;
1374                         mnt->acregmin = option;
1375                         break;
1376                 case Opt_acregmax:
1377                         if (nfs_get_option_ul(args, &option))
1378                                 goto out_invalid_value;
1379                         mnt->acregmax = option;
1380                         break;
1381                 case Opt_acdirmin:
1382                         if (nfs_get_option_ul(args, &option))
1383                                 goto out_invalid_value;
1384                         mnt->acdirmin = option;
1385                         break;
1386                 case Opt_acdirmax:
1387                         if (nfs_get_option_ul(args, &option))
1388                                 goto out_invalid_value;
1389                         mnt->acdirmax = option;
1390                         break;
1391                 case Opt_actimeo:
1392                         if (nfs_get_option_ul(args, &option))
1393                                 goto out_invalid_value;
1394                         mnt->acregmin = mnt->acregmax =
1395                         mnt->acdirmin = mnt->acdirmax = option;
1396                         break;
1397                 case Opt_namelen:
1398                         if (nfs_get_option_ul(args, &option))
1399                                 goto out_invalid_value;
1400                         mnt->namlen = option;
1401                         break;
1402                 case Opt_mountport:
1403                         if (nfs_get_option_ul(args, &option) ||
1404                             option > USHRT_MAX)
1405                                 goto out_invalid_value;
1406                         mnt->mount_server.port = option;
1407                         break;
1408                 case Opt_mountvers:
1409                         if (nfs_get_option_ul(args, &option) ||
1410                             option < NFS_MNT_VERSION ||
1411                             option > NFS_MNT3_VERSION)
1412                                 goto out_invalid_value;
1413                         mnt->mount_server.version = option;
1414                         break;
1415                 case Opt_minorversion:
1416                         if (nfs_get_option_ul(args, &option))
1417                                 goto out_invalid_value;
1418                         if (option > NFS4_MAX_MINOR_VERSION)
1419                                 goto out_invalid_value;
1420                         mnt->minorversion = option;
1421                         break;
1422
1423                 /*
1424                  * options that take text values
1425                  */
1426                 case Opt_nfsvers:
1427                         string = match_strdup(args);
1428                         if (string == NULL)
1429                                 goto out_nomem;
1430                         rc = nfs_parse_version_string(string, mnt, args);
1431                         kfree(string);
1432                         if (!rc)
1433                                 goto out_invalid_value;
1434                         break;
1435                 case Opt_sec:
1436                         string = match_strdup(args);
1437                         if (string == NULL)
1438                                 goto out_nomem;
1439                         rc = nfs_parse_security_flavors(string, mnt);
1440                         kfree(string);
1441                         if (!rc) {
1442                                 dfprintk(MOUNT, "NFS:   unrecognized "
1443                                                 "security flavor\n");
1444                                 return 0;
1445                         }
1446                         break;
1447                 case Opt_proto:
1448                         string = match_strdup(args);
1449                         if (string == NULL)
1450                                 goto out_nomem;
1451                         token = match_token(string,
1452                                             nfs_xprt_protocol_tokens, args);
1453
1454                         protofamily = AF_INET;
1455                         switch (token) {
1456                         case Opt_xprt_udp6:
1457                                 protofamily = AF_INET6;
1458                                 /* fall through */
1459                         case Opt_xprt_udp:
1460                                 mnt->flags &= ~NFS_MOUNT_TCP;
1461                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1462                                 break;
1463                         case Opt_xprt_tcp6:
1464                                 protofamily = AF_INET6;
1465                                 /* fall through */
1466                         case Opt_xprt_tcp:
1467                                 mnt->flags |= NFS_MOUNT_TCP;
1468                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1469                                 break;
1470                         case Opt_xprt_rdma6:
1471                                 protofamily = AF_INET6;
1472                                 /* fall through */
1473                         case Opt_xprt_rdma:
1474                                 /* vector side protocols to TCP */
1475                                 mnt->flags |= NFS_MOUNT_TCP;
1476                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1477                                 xprt_load_transport(string);
1478                                 break;
1479                         default:
1480                                 dfprintk(MOUNT, "NFS:   unrecognized "
1481                                                 "transport protocol\n");
1482                                 kfree(string);
1483                                 return 0;
1484                         }
1485                         kfree(string);
1486                         break;
1487                 case Opt_mountproto:
1488                         string = match_strdup(args);
1489                         if (string == NULL)
1490                                 goto out_nomem;
1491                         token = match_token(string,
1492                                             nfs_xprt_protocol_tokens, args);
1493                         kfree(string);
1494
1495                         mountfamily = AF_INET;
1496                         switch (token) {
1497                         case Opt_xprt_udp6:
1498                                 mountfamily = AF_INET6;
1499                                 /* fall through */
1500                         case Opt_xprt_udp:
1501                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1502                                 break;
1503                         case Opt_xprt_tcp6:
1504                                 mountfamily = AF_INET6;
1505                                 /* fall through */
1506                         case Opt_xprt_tcp:
1507                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1508                                 break;
1509                         case Opt_xprt_rdma: /* not used for side protocols */
1510                         default:
1511                                 dfprintk(MOUNT, "NFS:   unrecognized "
1512                                                 "transport protocol\n");
1513                                 return 0;
1514                         }
1515                         break;
1516                 case Opt_addr:
1517                         string = match_strdup(args);
1518                         if (string == NULL)
1519                                 goto out_nomem;
1520                         mnt->nfs_server.addrlen =
1521                                 rpc_pton(mnt->net, string, strlen(string),
1522                                         (struct sockaddr *)
1523                                         &mnt->nfs_server.address,
1524                                         sizeof(mnt->nfs_server.address));
1525                         kfree(string);
1526                         if (mnt->nfs_server.addrlen == 0)
1527                                 goto out_invalid_address;
1528                         break;
1529                 case Opt_clientaddr:
1530                         if (nfs_get_option_str(args, &mnt->client_address))
1531                                 goto out_nomem;
1532                         break;
1533                 case Opt_mounthost:
1534                         if (nfs_get_option_str(args,
1535                                                &mnt->mount_server.hostname))
1536                                 goto out_nomem;
1537                         break;
1538                 case Opt_mountaddr:
1539                         string = match_strdup(args);
1540                         if (string == NULL)
1541                                 goto out_nomem;
1542                         mnt->mount_server.addrlen =
1543                                 rpc_pton(mnt->net, string, strlen(string),
1544                                         (struct sockaddr *)
1545                                         &mnt->mount_server.address,
1546                                         sizeof(mnt->mount_server.address));
1547                         kfree(string);
1548                         if (mnt->mount_server.addrlen == 0)
1549                                 goto out_invalid_address;
1550                         break;
1551                 case Opt_lookupcache:
1552                         string = match_strdup(args);
1553                         if (string == NULL)
1554                                 goto out_nomem;
1555                         token = match_token(string,
1556                                         nfs_lookupcache_tokens, args);
1557                         kfree(string);
1558                         switch (token) {
1559                                 case Opt_lookupcache_all:
1560                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1561                                         break;
1562                                 case Opt_lookupcache_positive:
1563                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1564                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1565                                         break;
1566                                 case Opt_lookupcache_none:
1567                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1568                                         break;
1569                                 default:
1570                                         dfprintk(MOUNT, "NFS:   invalid "
1571                                                         "lookupcache argument\n");
1572                                         return 0;
1573                         };
1574                         break;
1575                 case Opt_fscache_uniq:
1576                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1577                                 goto out_nomem;
1578                         mnt->options |= NFS_OPTION_FSCACHE;
1579                         break;
1580                 case Opt_local_lock:
1581                         string = match_strdup(args);
1582                         if (string == NULL)
1583                                 goto out_nomem;
1584                         token = match_token(string, nfs_local_lock_tokens,
1585                                         args);
1586                         kfree(string);
1587                         switch (token) {
1588                         case Opt_local_lock_all:
1589                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1590                                                NFS_MOUNT_LOCAL_FCNTL);
1591                                 break;
1592                         case Opt_local_lock_flock:
1593                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1594                                 break;
1595                         case Opt_local_lock_posix:
1596                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1597                                 break;
1598                         case Opt_local_lock_none:
1599                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1600                                                 NFS_MOUNT_LOCAL_FCNTL);
1601                                 break;
1602                         default:
1603                                 dfprintk(MOUNT, "NFS:   invalid "
1604                                                 "local_lock argument\n");
1605                                 return 0;
1606                         };
1607                         break;
1608
1609                 /*
1610                  * Special options
1611                  */
1612                 case Opt_sloppy:
1613                         sloppy = 1;
1614                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1615                         break;
1616                 case Opt_userspace:
1617                 case Opt_deprecated:
1618                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1619                                         "'%s'\n", p);
1620                         break;
1621
1622                 default:
1623                         invalid_option = 1;
1624                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1625                                         "'%s'\n", p);
1626                 }
1627         }
1628
1629         if (!sloppy && invalid_option)
1630                 return 0;
1631
1632         if (mnt->minorversion && mnt->version != 4)
1633                 goto out_minorversion_mismatch;
1634
1635         if (mnt->options & NFS_OPTION_MIGRATION &&
1636             (mnt->version != 4 || mnt->minorversion != 0))
1637                 goto out_migration_misuse;
1638
1639         /*
1640          * verify that any proto=/mountproto= options match the address
1641          * families in the addr=/mountaddr= options.
1642          */
1643         if (protofamily != AF_UNSPEC &&
1644             protofamily != mnt->nfs_server.address.ss_family)
1645                 goto out_proto_mismatch;
1646
1647         if (mountfamily != AF_UNSPEC) {
1648                 if (mnt->mount_server.addrlen) {
1649                         if (mountfamily != mnt->mount_server.address.ss_family)
1650                                 goto out_mountproto_mismatch;
1651                 } else {
1652                         if (mountfamily != mnt->nfs_server.address.ss_family)
1653                                 goto out_mountproto_mismatch;
1654                 }
1655         }
1656
1657         return 1;
1658
1659 out_mountproto_mismatch:
1660         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1661                          "option\n");
1662         return 0;
1663 out_proto_mismatch:
1664         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1665         return 0;
1666 out_invalid_address:
1667         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1668         return 0;
1669 out_invalid_value:
1670         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1671         return 0;
1672 out_minorversion_mismatch:
1673         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1674                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1675         return 0;
1676 out_migration_misuse:
1677         printk(KERN_INFO
1678                 "NFS: 'migration' not supported for this NFS version\n");
1679         return 0;
1680 out_nomem:
1681         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1682         return 0;
1683 out_security_failure:
1684         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1685         return 0;
1686 }
1687
1688 /*
1689  * Ensure that a specified authtype in args->auth_info is supported by
1690  * the server. Returns 0 and sets args->selected_flavor if it's ok, and
1691  * -EACCES if not.
1692  */
1693 static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
1694                         rpc_authflavor_t *server_authlist, unsigned int count)
1695 {
1696         rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
1697         bool found_auth_null = false;
1698         unsigned int i;
1699
1700         /*
1701          * If the sec= mount option is used, the specified flavor or AUTH_NULL
1702          * must be in the list returned by the server.
1703          *
1704          * AUTH_NULL has a special meaning when it's in the server list - it
1705          * means that the server will ignore the rpc creds, so any flavor
1706          * can be used but still use the sec= that was specified.
1707          *
1708          * Note also that the MNT procedure in MNTv1 does not return a list
1709          * of supported security flavors. In this case, nfs_mount() fabricates
1710          * a security flavor list containing just AUTH_NULL.
1711          */
1712         for (i = 0; i < count; i++) {
1713                 flavor = server_authlist[i];
1714
1715                 if (nfs_auth_info_match(&args->auth_info, flavor))
1716                         goto out;
1717
1718                 if (flavor == RPC_AUTH_NULL)
1719                         found_auth_null = true;
1720         }
1721
1722         if (found_auth_null) {
1723                 flavor = args->auth_info.flavors[0];
1724                 goto out;
1725         }
1726
1727         dfprintk(MOUNT,
1728                  "NFS: specified auth flavors not supported by server\n");
1729         return -EACCES;
1730
1731 out:
1732         args->selected_flavor = flavor;
1733         dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
1734         return 0;
1735 }
1736
1737 /*
1738  * Use the remote server's MOUNT service to request the NFS file handle
1739  * corresponding to the provided path.
1740  */
1741 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1742                              struct nfs_fh *root_fh,
1743                              rpc_authflavor_t *server_authlist,
1744                              unsigned int *server_authlist_len)
1745 {
1746         struct nfs_mount_request request = {
1747                 .sap            = (struct sockaddr *)
1748                                                 &args->mount_server.address,
1749                 .dirpath        = args->nfs_server.export_path,
1750                 .protocol       = args->mount_server.protocol,
1751                 .fh             = root_fh,
1752                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1753                 .auth_flav_len  = server_authlist_len,
1754                 .auth_flavs     = server_authlist,
1755                 .net            = args->net,
1756         };
1757         int status;
1758
1759         if (args->mount_server.version == 0) {
1760                 switch (args->version) {
1761                         default:
1762                                 args->mount_server.version = NFS_MNT3_VERSION;
1763                                 break;
1764                         case 2:
1765                                 args->mount_server.version = NFS_MNT_VERSION;
1766                 }
1767         }
1768         request.version = args->mount_server.version;
1769
1770         if (args->mount_server.hostname)
1771                 request.hostname = args->mount_server.hostname;
1772         else
1773                 request.hostname = args->nfs_server.hostname;
1774
1775         /*
1776          * Construct the mount server's address.
1777          */
1778         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1779                 memcpy(request.sap, &args->nfs_server.address,
1780                        args->nfs_server.addrlen);
1781                 args->mount_server.addrlen = args->nfs_server.addrlen;
1782         }
1783         request.salen = args->mount_server.addrlen;
1784         nfs_set_port(request.sap, &args->mount_server.port, 0);
1785
1786         /*
1787          * Now ask the mount server to map our export path
1788          * to a file handle.
1789          */
1790         status = nfs_mount(&request);
1791         if (status != 0) {
1792                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1793                                 request.hostname, status);
1794                 return status;
1795         }
1796
1797         return 0;
1798 }
1799
1800 static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1801                                         struct nfs_subversion *nfs_mod)
1802 {
1803         int status;
1804         unsigned int i;
1805         bool tried_auth_unix = false;
1806         bool auth_null_in_list = false;
1807         struct nfs_server *server = ERR_PTR(-EACCES);
1808         struct nfs_parsed_mount_data *args = mount_info->parsed;
1809         rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1810         unsigned int authlist_len = ARRAY_SIZE(authlist);
1811
1812         status = nfs_request_mount(args, mount_info->mntfh, authlist,
1813                                         &authlist_len);
1814         if (status)
1815                 return ERR_PTR(status);
1816
1817         /*
1818          * Was a sec= authflavor specified in the options? First, verify
1819          * whether the server supports it, and then just try to use it if so.
1820          */
1821         if (args->auth_info.flavor_len > 0) {
1822                 status = nfs_verify_authflavors(args, authlist, authlist_len);
1823                 dfprintk(MOUNT, "NFS: using auth flavor %u\n",
1824                          args->selected_flavor);
1825                 if (status)
1826                         return ERR_PTR(status);
1827                 return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1828         }
1829
1830         /*
1831          * No sec= option was provided. RFC 2623, section 2.7 suggests we
1832          * SHOULD prefer the flavor listed first. However, some servers list
1833          * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1834          */
1835         for (i = 0; i < authlist_len; ++i) {
1836                 rpc_authflavor_t flavor;
1837                 struct rpcsec_gss_info info;
1838
1839                 flavor = authlist[i];
1840                 switch (flavor) {
1841                 case RPC_AUTH_UNIX:
1842                         tried_auth_unix = true;
1843                         break;
1844                 case RPC_AUTH_NULL:
1845                         auth_null_in_list = true;
1846                         continue;
1847                 default:
1848                         if (rpcauth_get_gssinfo(flavor, &info) != 0)
1849                                 continue;
1850                         /* Fallthrough */
1851                 }
1852                 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1853                 args->selected_flavor = flavor;
1854                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1855                 if (!IS_ERR(server))
1856                         return server;
1857         }
1858
1859         /*
1860          * Nothing we tried so far worked. At this point, give up if we've
1861          * already tried AUTH_UNIX or if the server's list doesn't contain
1862          * AUTH_NULL
1863          */
1864         if (tried_auth_unix || !auth_null_in_list)
1865                 return server;
1866
1867         /* Last chance! Try AUTH_UNIX */
1868         dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1869         args->selected_flavor = RPC_AUTH_UNIX;
1870         return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1871 }
1872
1873 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1874                              struct nfs_mount_info *mount_info,
1875                              struct nfs_subversion *nfs_mod)
1876 {
1877         struct nfs_server *server;
1878
1879         if (mount_info->parsed->need_mount)
1880                 server = nfs_try_mount_request(mount_info, nfs_mod);
1881         else
1882                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1883
1884         if (IS_ERR(server))
1885                 return ERR_CAST(server);
1886
1887         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1888 }
1889 EXPORT_SYMBOL_GPL(nfs_try_mount);
1890
1891 /*
1892  * Split "dev_name" into "hostname:export_path".
1893  *
1894  * The leftmost colon demarks the split between the server's hostname
1895  * and the export path.  If the hostname starts with a left square
1896  * bracket, then it may contain colons.
1897  *
1898  * Note: caller frees hostname and export path, even on error.
1899  */
1900 static int nfs_parse_devname(const char *dev_name,
1901                              char **hostname, size_t maxnamlen,
1902                              char **export_path, size_t maxpathlen)
1903 {
1904         size_t len;
1905         char *end;
1906
1907         if (unlikely(!dev_name || !*dev_name)) {
1908                 dfprintk(MOUNT, "NFS: device name not specified\n");
1909                 return -EINVAL;
1910         }
1911
1912         /* Is the host name protected with square brakcets? */
1913         if (*dev_name == '[') {
1914                 end = strchr(++dev_name, ']');
1915                 if (end == NULL || end[1] != ':')
1916                         goto out_bad_devname;
1917
1918                 len = end - dev_name;
1919                 end++;
1920         } else {
1921                 char *comma;
1922
1923                 end = strchr(dev_name, ':');
1924                 if (end == NULL)
1925                         goto out_bad_devname;
1926                 len = end - dev_name;
1927
1928                 /* kill possible hostname list: not supported */
1929                 comma = strchr(dev_name, ',');
1930                 if (comma != NULL && comma < end)
1931                         len = comma - dev_name;
1932         }
1933
1934         if (len > maxnamlen)
1935                 goto out_hostname;
1936
1937         /* N.B. caller will free nfs_server.hostname in all cases */
1938         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1939         if (*hostname == NULL)
1940                 goto out_nomem;
1941         len = strlen(++end);
1942         if (len > maxpathlen)
1943                 goto out_path;
1944         *export_path = kstrndup(end, len, GFP_KERNEL);
1945         if (!*export_path)
1946                 goto out_nomem;
1947
1948         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1949         return 0;
1950
1951 out_bad_devname:
1952         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1953         return -EINVAL;
1954
1955 out_nomem:
1956         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1957         return -ENOMEM;
1958
1959 out_hostname:
1960         dfprintk(MOUNT, "NFS: server hostname too long\n");
1961         return -ENAMETOOLONG;
1962
1963 out_path:
1964         dfprintk(MOUNT, "NFS: export pathname too long\n");
1965         return -ENAMETOOLONG;
1966 }
1967
1968 /*
1969  * Validate the NFS2/NFS3 mount data
1970  * - fills in the mount root filehandle
1971  *
1972  * For option strings, user space handles the following behaviors:
1973  *
1974  * + DNS: mapping server host name to IP address ("addr=" option)
1975  *
1976  * + failure mode: how to behave if a mount request can't be handled
1977  *   immediately ("fg/bg" option)
1978  *
1979  * + retry: how often to retry a mount request ("retry=" option)
1980  *
1981  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1982  *   mountproto=tcp after mountproto=udp, and so on
1983  */
1984 static int nfs23_validate_mount_data(void *options,
1985                                      struct nfs_parsed_mount_data *args,
1986                                      struct nfs_fh *mntfh,
1987                                      const char *dev_name)
1988 {
1989         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1990         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1991         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1992
1993         if (data == NULL)
1994                 goto out_no_data;
1995
1996         args->version = NFS_DEFAULT_VERSION;
1997         switch (data->version) {
1998         case 1:
1999                 data->namlen = 0; /* fall through */
2000         case 2:
2001                 data->bsize = 0; /* fall through */
2002         case 3:
2003                 if (data->flags & NFS_MOUNT_VER3)
2004                         goto out_no_v3;
2005                 data->root.size = NFS2_FHSIZE;
2006                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
2007                 /* Turn off security negotiation */
2008                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
2009                 /* fall through */
2010         case 4:
2011                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
2012                         goto out_no_sec;
2013                 /* fall through */
2014         case 5:
2015                 memset(data->context, 0, sizeof(data->context));
2016                 /* fall through */
2017         case 6:
2018                 if (data->flags & NFS_MOUNT_VER3) {
2019                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
2020                                 goto out_invalid_fh;
2021                         mntfh->size = data->root.size;
2022                         args->version = 3;
2023                 } else {
2024                         mntfh->size = NFS2_FHSIZE;
2025                         args->version = 2;
2026                 }
2027
2028
2029                 memcpy(mntfh->data, data->root.data, mntfh->size);
2030                 if (mntfh->size < sizeof(mntfh->data))
2031                         memset(mntfh->data + mntfh->size, 0,
2032                                sizeof(mntfh->data) - mntfh->size);
2033
2034                 /*
2035                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
2036                  * can deal with.
2037                  */
2038                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
2039                 args->flags             |= extra_flags;
2040                 args->rsize             = data->rsize;
2041                 args->wsize             = data->wsize;
2042                 args->timeo             = data->timeo;
2043                 args->retrans           = data->retrans;
2044                 args->acregmin          = data->acregmin;
2045                 args->acregmax          = data->acregmax;
2046                 args->acdirmin          = data->acdirmin;
2047                 args->acdirmax          = data->acdirmax;
2048                 args->need_mount        = false;
2049
2050                 memcpy(sap, &data->addr, sizeof(data->addr));
2051                 args->nfs_server.addrlen = sizeof(data->addr);
2052                 args->nfs_server.port = ntohs(data->addr.sin_port);
2053                 if (sap->sa_family != AF_INET ||
2054                     !nfs_verify_server_address(sap))
2055                         goto out_no_address;
2056
2057                 if (!(data->flags & NFS_MOUNT_TCP))
2058                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
2059                 /* N.B. caller will free nfs_server.hostname in all cases */
2060                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
2061                 args->namlen            = data->namlen;
2062                 args->bsize             = data->bsize;
2063
2064                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
2065                         args->selected_flavor = data->pseudoflavor;
2066                 else
2067                         args->selected_flavor = RPC_AUTH_UNIX;
2068                 if (!args->nfs_server.hostname)
2069                         goto out_nomem;
2070
2071                 if (!(data->flags & NFS_MOUNT_NONLM))
2072                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
2073                                          NFS_MOUNT_LOCAL_FCNTL);
2074                 else
2075                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
2076                                         NFS_MOUNT_LOCAL_FCNTL);
2077                 /*
2078                  * The legacy version 6 binary mount data from userspace has a
2079                  * field used only to transport selinux information into the
2080                  * the kernel.  To continue to support that functionality we
2081                  * have a touch of selinux knowledge here in the NFS code. The
2082                  * userspace code converted context=blah to just blah so we are
2083                  * converting back to the full string selinux understands.
2084                  */
2085                 if (data->context[0]){
2086 #ifdef CONFIG_SECURITY_SELINUX
2087                         int rc;
2088                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
2089                         rc = security_add_mnt_opt("context", data->context,
2090                                         strlen(data->context), &args->lsm_opts);
2091                         if (rc)
2092                                 return rc;
2093 #else
2094                         return -EINVAL;
2095 #endif
2096                 }
2097
2098                 break;
2099         default:
2100                 return NFS_TEXT_DATA;
2101         }
2102
2103         return 0;
2104
2105 out_no_data:
2106         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2107         return -EINVAL;
2108
2109 out_no_v3:
2110         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2111                  data->version);
2112         return -EINVAL;
2113
2114 out_no_sec:
2115         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2116         return -EINVAL;
2117
2118 out_nomem:
2119         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2120         return -ENOMEM;
2121
2122 out_no_address:
2123         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2124         return -EINVAL;
2125
2126 out_invalid_fh:
2127         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2128         return -EINVAL;
2129 }
2130
2131 #if IS_ENABLED(CONFIG_NFS_V4)
2132 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2133                                    void *options,
2134                                    struct nfs_parsed_mount_data *args,
2135                                    struct nfs_fh *mntfh,
2136                                    const char *dev_name)
2137 {
2138         if (fs_type == &nfs_fs_type)
2139                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2140         return nfs4_validate_mount_data(options, args, dev_name);
2141 }
2142 #else
2143 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2144                                    void *options,
2145                                    struct nfs_parsed_mount_data *args,
2146                                    struct nfs_fh *mntfh,
2147                                    const char *dev_name)
2148 {
2149         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2150 }
2151 #endif
2152
2153 static int nfs_validate_text_mount_data(void *options,
2154                                         struct nfs_parsed_mount_data *args,
2155                                         const char *dev_name)
2156 {
2157         int port = 0;
2158         int max_namelen = PAGE_SIZE;
2159         int max_pathlen = NFS_MAXPATHLEN;
2160         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2161
2162         if (nfs_parse_mount_options((char *)options, args) == 0)
2163                 return -EINVAL;
2164
2165         if (!nfs_verify_server_address(sap))
2166                 goto out_no_address;
2167
2168         if (args->version == 4) {
2169 #if IS_ENABLED(CONFIG_NFS_V4)
2170                 if (args->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
2171                         port = NFS_RDMA_PORT;
2172                 else
2173                         port = NFS_PORT;
2174                 max_namelen = NFS4_MAXNAMLEN;
2175                 max_pathlen = NFS4_MAXPATHLEN;
2176                 nfs_validate_transport_protocol(args);
2177                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2178                         goto out_invalid_transport_udp;
2179                 nfs4_validate_mount_flags(args);
2180 #else
2181                 goto out_v4_not_compiled;
2182 #endif /* CONFIG_NFS_V4 */
2183         } else {
2184                 nfs_set_mount_transport_protocol(args);
2185                 if (args->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
2186                         port = NFS_RDMA_PORT;
2187         }
2188
2189         nfs_set_port(sap, &args->nfs_server.port, port);
2190
2191         return nfs_parse_devname(dev_name,
2192                                    &args->nfs_server.hostname,
2193                                    max_namelen,
2194                                    &args->nfs_server.export_path,
2195                                    max_pathlen);
2196
2197 #if !IS_ENABLED(CONFIG_NFS_V4)
2198 out_v4_not_compiled:
2199         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2200         return -EPROTONOSUPPORT;
2201 #else
2202 out_invalid_transport_udp:
2203         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2204         return -EINVAL;
2205 #endif /* !CONFIG_NFS_V4 */
2206
2207 out_no_address:
2208         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2209         return -EINVAL;
2210 }
2211
2212 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
2213                 | NFS_MOUNT_SECURE \
2214                 | NFS_MOUNT_TCP \
2215                 | NFS_MOUNT_VER3 \
2216                 | NFS_MOUNT_KERBEROS \
2217                 | NFS_MOUNT_NONLM \
2218                 | NFS_MOUNT_BROKEN_SUID \
2219                 | NFS_MOUNT_STRICTLOCK \
2220                 | NFS_MOUNT_LEGACY_INTERFACE)
2221
2222 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
2223                 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
2224
2225 static int
2226 nfs_compare_remount_data(struct nfs_server *nfss,
2227                          struct nfs_parsed_mount_data *data)
2228 {
2229         if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
2230             data->rsize != nfss->rsize ||
2231             data->wsize != nfss->wsize ||
2232             data->version != nfss->nfs_client->rpc_ops->version ||
2233             data->minorversion != nfss->nfs_client->cl_minorversion ||
2234             data->retrans != nfss->client->cl_timeout->to_retries ||
2235             !nfs_auth_info_match(&data->auth_info, nfss->client->cl_auth->au_flavor) ||
2236             data->acregmin != nfss->acregmin / HZ ||
2237             data->acregmax != nfss->acregmax / HZ ||
2238             data->acdirmin != nfss->acdirmin / HZ ||
2239             data->acdirmax != nfss->acdirmax / HZ ||
2240             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2241             data->nfs_server.port != nfss->port ||
2242             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2243             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2244                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2245                 return -EINVAL;
2246
2247         return 0;
2248 }
2249
2250 int
2251 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2252 {
2253         int error;
2254         struct nfs_server *nfss = sb->s_fs_info;
2255         struct nfs_parsed_mount_data *data;
2256         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2257         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2258         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2259
2260         sync_filesystem(sb);
2261
2262         /*
2263          * Userspace mount programs that send binary options generally send
2264          * them populated with default values. We have no way to know which
2265          * ones were explicitly specified. Fall back to legacy behavior and
2266          * just return success.
2267          */
2268         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2269             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2270                                            options->version <= 6))))
2271                 return 0;
2272
2273         data = nfs_alloc_parsed_mount_data();
2274         if (data == NULL)
2275                 return -ENOMEM;
2276
2277         /* fill out struct with values from existing mount */
2278         data->flags = nfss->flags;
2279         data->rsize = nfss->rsize;
2280         data->wsize = nfss->wsize;
2281         data->retrans = nfss->client->cl_timeout->to_retries;
2282         data->selected_flavor = nfss->client->cl_auth->au_flavor;
2283         data->acregmin = nfss->acregmin / HZ;
2284         data->acregmax = nfss->acregmax / HZ;
2285         data->acdirmin = nfss->acdirmin / HZ;
2286         data->acdirmax = nfss->acdirmax / HZ;
2287         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2288         data->nfs_server.port = nfss->port;
2289         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2290         data->version = nfsvers;
2291         data->minorversion = nfss->nfs_client->cl_minorversion;
2292         data->net = current->nsproxy->net_ns;
2293         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2294                 data->nfs_server.addrlen);
2295
2296         /* overwrite those values with any that were specified */
2297         error = -EINVAL;
2298         if (!nfs_parse_mount_options((char *)options, data))
2299                 goto out;
2300
2301         /*
2302          * noac is a special case. It implies -o sync, but that's not
2303          * necessarily reflected in the mtab options. do_remount_sb
2304          * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the
2305          * remount options, so we have to explicitly reset it.
2306          */
2307         if (data->flags & NFS_MOUNT_NOAC)
2308                 *flags |= SB_SYNCHRONOUS;
2309
2310         /* compare new mount options with old ones */
2311         error = nfs_compare_remount_data(nfss, data);
2312         if (!error)
2313                 error = security_sb_remount(sb, data->lsm_opts);
2314 out:
2315         nfs_free_parsed_mount_data(data);
2316         return error;
2317 }
2318 EXPORT_SYMBOL_GPL(nfs_remount);
2319
2320 /*
2321  * Initialise the common bits of the superblock
2322  */
2323 static void nfs_initialise_sb(struct super_block *sb)
2324 {
2325         struct nfs_server *server = NFS_SB(sb);
2326
2327         sb->s_magic = NFS_SUPER_MAGIC;
2328
2329         /* We probably want something more informative here */
2330         snprintf(sb->s_id, sizeof(sb->s_id),
2331                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2332
2333         if (sb->s_blocksize == 0)
2334                 sb->s_blocksize = nfs_block_bits(server->wsize,
2335                                                  &sb->s_blocksize_bits);
2336
2337         nfs_super_set_maxbytes(sb, server->maxfilesize);
2338 }
2339
2340 /*
2341  * Finish setting up an NFS2/3 superblock
2342  */
2343 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2344 {
2345         struct nfs_parsed_mount_data *data = mount_info->parsed;
2346         struct nfs_server *server = NFS_SB(sb);
2347
2348         sb->s_blocksize_bits = 0;
2349         sb->s_blocksize = 0;
2350         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2351         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2352         if (data && data->bsize)
2353                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2354
2355         if (server->nfs_client->rpc_ops->version != 2) {
2356                 /* The VFS shouldn't apply the umask to mode bits. We will do
2357                  * so ourselves when necessary.
2358                  */
2359                 sb->s_flags |= SB_POSIXACL;
2360                 sb->s_time_gran = 1;
2361                 sb->s_export_op = &nfs_export_ops;
2362         }
2363
2364         nfs_initialise_sb(sb);
2365 }
2366 EXPORT_SYMBOL_GPL(nfs_fill_super);
2367
2368 /*
2369  * Finish setting up a cloned NFS2/3/4 superblock
2370  */
2371 static void nfs_clone_super(struct super_block *sb,
2372                             struct nfs_mount_info *mount_info)
2373 {
2374         const struct super_block *old_sb = mount_info->cloned->sb;
2375         struct nfs_server *server = NFS_SB(sb);
2376
2377         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2378         sb->s_blocksize = old_sb->s_blocksize;
2379         sb->s_maxbytes = old_sb->s_maxbytes;
2380         sb->s_xattr = old_sb->s_xattr;
2381         sb->s_op = old_sb->s_op;
2382         sb->s_time_gran = 1;
2383         sb->s_export_op = old_sb->s_export_op;
2384
2385         if (server->nfs_client->rpc_ops->version != 2) {
2386                 /* The VFS shouldn't apply the umask to mode bits. We will do
2387                  * so ourselves when necessary.
2388                  */
2389                 sb->s_flags |= SB_POSIXACL;
2390         }
2391
2392         nfs_initialise_sb(sb);
2393 }
2394
2395 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2396 {
2397         const struct nfs_server *a = s->s_fs_info;
2398         const struct rpc_clnt *clnt_a = a->client;
2399         const struct rpc_clnt *clnt_b = b->client;
2400
2401         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2402                 goto Ebusy;
2403         if (a->nfs_client != b->nfs_client)
2404                 goto Ebusy;
2405         if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
2406                 goto Ebusy;
2407         if (a->wsize != b->wsize)
2408                 goto Ebusy;
2409         if (a->rsize != b->rsize)
2410                 goto Ebusy;
2411         if (a->acregmin != b->acregmin)
2412                 goto Ebusy;
2413         if (a->acregmax != b->acregmax)
2414                 goto Ebusy;
2415         if (a->acdirmin != b->acdirmin)
2416                 goto Ebusy;
2417         if (a->acdirmax != b->acdirmax)
2418                 goto Ebusy;
2419         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2420                 goto Ebusy;
2421         return 1;
2422 Ebusy:
2423         return 0;
2424 }
2425
2426 struct nfs_sb_mountdata {
2427         struct nfs_server *server;
2428         int mntflags;
2429 };
2430
2431 static int nfs_set_super(struct super_block *s, void *data)
2432 {
2433         struct nfs_sb_mountdata *sb_mntdata = data;
2434         struct nfs_server *server = sb_mntdata->server;
2435         int ret;
2436
2437         s->s_flags = sb_mntdata->mntflags;
2438         s->s_fs_info = server;
2439         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2440         ret = set_anon_super(s, server);
2441         if (ret == 0)
2442                 server->s_dev = s->s_dev;
2443         return ret;
2444 }
2445
2446 static int nfs_compare_super_address(struct nfs_server *server1,
2447                                      struct nfs_server *server2)
2448 {
2449         struct sockaddr *sap1, *sap2;
2450         struct rpc_xprt *xprt1 = server1->client->cl_xprt;
2451         struct rpc_xprt *xprt2 = server2->client->cl_xprt;
2452
2453         if (!net_eq(xprt1->xprt_net, xprt2->xprt_net))
2454                 return 0;
2455
2456         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2457         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2458
2459         if (sap1->sa_family != sap2->sa_family)
2460                 return 0;
2461
2462         switch (sap1->sa_family) {
2463         case AF_INET: {
2464                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2465                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2466                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2467                         return 0;
2468                 if (sin1->sin_port != sin2->sin_port)
2469                         return 0;
2470                 break;
2471         }
2472         case AF_INET6: {
2473                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2474                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2475                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2476                         return 0;
2477                 if (sin1->sin6_port != sin2->sin6_port)
2478                         return 0;
2479                 break;
2480         }
2481         default:
2482                 return 0;
2483         }
2484
2485         return 1;
2486 }
2487
2488 static int nfs_compare_userns(const struct nfs_server *old,
2489                 const struct nfs_server *new)
2490 {
2491         const struct user_namespace *oldns = &init_user_ns;
2492         const struct user_namespace *newns = &init_user_ns;
2493
2494         if (old->client && old->client->cl_cred)
2495                 oldns = old->client->cl_cred->user_ns;
2496         if (new->client && new->client->cl_cred)
2497                 newns = new->client->cl_cred->user_ns;
2498         if (oldns != newns)
2499                 return 0;
2500         return 1;
2501 }
2502
2503 static int nfs_compare_super(struct super_block *sb, void *data)
2504 {
2505         struct nfs_sb_mountdata *sb_mntdata = data;
2506         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2507         int mntflags = sb_mntdata->mntflags;
2508
2509         if (!nfs_compare_super_address(old, server))
2510                 return 0;
2511         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2512         if (old->flags & NFS_MOUNT_UNSHARED)
2513                 return 0;
2514         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2515                 return 0;
2516         if (!nfs_compare_userns(old, server))
2517                 return 0;
2518         return nfs_compare_mount_options(sb, server, mntflags);
2519 }
2520
2521 #ifdef CONFIG_NFS_FSCACHE
2522 static void nfs_get_cache_cookie(struct super_block *sb,
2523                                  struct nfs_parsed_mount_data *parsed,
2524                                  struct nfs_clone_mount *cloned)
2525 {
2526         struct nfs_server *nfss = NFS_SB(sb);
2527         char *uniq = NULL;
2528         int ulen = 0;
2529
2530         nfss->fscache_key = NULL;
2531         nfss->fscache = NULL;
2532
2533         if (parsed) {
2534                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2535                         return;
2536                 if (parsed->fscache_uniq) {
2537                         uniq = parsed->fscache_uniq;
2538                         ulen = strlen(parsed->fscache_uniq);
2539                 }
2540         } else if (cloned) {
2541                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2542                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2543                         return;
2544                 if (mnt_s->fscache_key) {
2545                         uniq = mnt_s->fscache_key->key.uniquifier;
2546                         ulen = mnt_s->fscache_key->key.uniq_len;
2547                 };
2548         } else
2549                 return;
2550
2551         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2552 }
2553 #else
2554 static void nfs_get_cache_cookie(struct super_block *sb,
2555                                  struct nfs_parsed_mount_data *parsed,
2556                                  struct nfs_clone_mount *cloned)
2557 {
2558 }
2559 #endif
2560
2561 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2562                         struct nfs_mount_info *mount_info)
2563 {
2564         int error;
2565         unsigned long kflags = 0, kflags_out = 0;
2566         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2567                 kflags |= SECURITY_LSM_NATIVE_LABELS;
2568
2569         error = security_sb_set_mnt_opts(s, mount_info->parsed->lsm_opts,
2570                                                 kflags, &kflags_out);
2571         if (error)
2572                 goto err;
2573
2574         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2575                 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2576                 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2577 err:
2578         return error;
2579 }
2580 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2581
2582 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2583                           struct nfs_mount_info *mount_info)
2584 {
2585         int error;
2586         unsigned long kflags = 0, kflags_out = 0;
2587
2588         /* clone any lsm security options from the parent to the new sb */
2589         if (d_inode(mntroot)->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2590                 return -ESTALE;
2591
2592         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2593                 kflags |= SECURITY_LSM_NATIVE_LABELS;
2594
2595         error = security_sb_clone_mnt_opts(mount_info->cloned->sb, s, kflags,
2596                         &kflags_out);
2597         if (error)
2598                 return error;
2599
2600         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2601                 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2602                 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2603         return 0;
2604 }
2605 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2606
2607 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2608                                    int flags, const char *dev_name,
2609                                    struct nfs_mount_info *mount_info,
2610                                    struct nfs_subversion *nfs_mod)
2611 {
2612         struct super_block *s;
2613         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2614         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2615         struct nfs_sb_mountdata sb_mntdata = {
2616                 .mntflags = flags,
2617                 .server = server,
2618         };
2619         int error;
2620
2621         if (server->flags & NFS_MOUNT_UNSHARED)
2622                 compare_super = NULL;
2623
2624         /* -o noac implies -o sync */
2625         if (server->flags & NFS_MOUNT_NOAC)
2626                 sb_mntdata.mntflags |= SB_SYNCHRONOUS;
2627
2628         if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
2629                 if (mount_info->cloned->sb->s_flags & SB_SYNCHRONOUS)
2630                         sb_mntdata.mntflags |= SB_SYNCHRONOUS;
2631
2632         /* Get a superblock - note that we may end up sharing one that already exists */
2633         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2634         if (IS_ERR(s)) {
2635                 mntroot = ERR_CAST(s);
2636                 goto out_err_nosb;
2637         }
2638
2639         if (s->s_fs_info != server) {
2640                 nfs_free_server(server);
2641                 server = NULL;
2642         } else {
2643                 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev),
2644                                              MINOR(server->s_dev));
2645                 if (error) {
2646                         mntroot = ERR_PTR(error);
2647                         goto error_splat_super;
2648                 }
2649                 s->s_bdi->ra_pages = server->rpages * NFS_MAX_READAHEAD;
2650                 server->super = s;
2651         }
2652
2653         if (!s->s_root) {
2654                 /* initial superblock/root creation */
2655                 mount_info->fill_super(s, mount_info);
2656                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2657                 if (!(server->flags & NFS_MOUNT_UNSHARED))
2658                         s->s_iflags |= SB_I_MULTIROOT;
2659         }
2660
2661         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2662         if (IS_ERR(mntroot))
2663                 goto error_splat_super;
2664
2665         error = mount_info->set_security(s, mntroot, mount_info);
2666         if (error)
2667                 goto error_splat_root;
2668
2669         s->s_flags |= SB_ACTIVE;
2670
2671 out:
2672         return mntroot;
2673
2674 out_err_nosb:
2675         nfs_free_server(server);
2676         goto out;
2677
2678 error_splat_root:
2679         dput(mntroot);
2680         mntroot = ERR_PTR(error);
2681 error_splat_super:
2682         deactivate_locked_super(s);
2683         goto out;
2684 }
2685 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2686
2687 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2688         int flags, const char *dev_name, void *raw_data)
2689 {
2690         struct nfs_mount_info mount_info = {
2691                 .fill_super = nfs_fill_super,
2692                 .set_security = nfs_set_sb_security,
2693         };
2694         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2695         struct nfs_subversion *nfs_mod;
2696         int error;
2697
2698         mount_info.parsed = nfs_alloc_parsed_mount_data();
2699         mount_info.mntfh = nfs_alloc_fhandle();
2700         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2701                 goto out;
2702
2703         /* Validate the mount data */
2704         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2705         if (error == NFS_TEXT_DATA)
2706                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2707         if (error < 0) {
2708                 mntroot = ERR_PTR(error);
2709                 goto out;
2710         }
2711
2712         nfs_mod = get_nfs_version(mount_info.parsed->version);
2713         if (IS_ERR(nfs_mod)) {
2714                 mntroot = ERR_CAST(nfs_mod);
2715                 goto out;
2716         }
2717
2718         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2719
2720         put_nfs_version(nfs_mod);
2721 out:
2722         nfs_free_parsed_mount_data(mount_info.parsed);
2723         nfs_free_fhandle(mount_info.mntfh);
2724         return mntroot;
2725 }
2726 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2727
2728 /*
2729  * Destroy an NFS2/3 superblock
2730  */
2731 void nfs_kill_super(struct super_block *s)
2732 {
2733         struct nfs_server *server = NFS_SB(s);
2734         dev_t dev = s->s_dev;
2735
2736         generic_shutdown_super(s);
2737
2738         nfs_fscache_release_super_cookie(s);
2739
2740         nfs_free_server(server);
2741         free_anon_bdev(dev);
2742 }
2743 EXPORT_SYMBOL_GPL(nfs_kill_super);
2744
2745 /*
2746  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2747  */
2748 static struct dentry *
2749 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2750                 const char *dev_name, void *raw_data)
2751 {
2752         struct nfs_clone_mount *data = raw_data;
2753         struct nfs_mount_info mount_info = {
2754                 .fill_super = nfs_clone_super,
2755                 .set_security = nfs_clone_sb_security,
2756                 .cloned = data,
2757         };
2758         struct nfs_server *server;
2759         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2760         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2761
2762         dprintk("--> nfs_xdev_mount()\n");
2763
2764         mount_info.mntfh = mount_info.cloned->fh;
2765
2766         /* create a new volume representation */
2767         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2768
2769         if (IS_ERR(server))
2770                 mntroot = ERR_CAST(server);
2771         else
2772                 mntroot = nfs_fs_mount_common(server, flags,
2773                                 dev_name, &mount_info, nfs_mod);
2774
2775         dprintk("<-- nfs_xdev_mount() = %ld\n",
2776                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2777         return mntroot;
2778 }
2779
2780 #if IS_ENABLED(CONFIG_NFS_V4)
2781
2782 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2783 {
2784         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2785                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2786 }
2787
2788 /*
2789  * Validate NFSv4 mount options
2790  */
2791 static int nfs4_validate_mount_data(void *options,
2792                                     struct nfs_parsed_mount_data *args,
2793                                     const char *dev_name)
2794 {
2795         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2796         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2797         char *c;
2798
2799         if (data == NULL)
2800                 goto out_no_data;
2801
2802         args->version = 4;
2803
2804         switch (data->version) {
2805         case 1:
2806                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2807                         goto out_no_address;
2808                 if (data->host_addrlen == 0)
2809                         goto out_no_address;
2810                 args->nfs_server.addrlen = data->host_addrlen;
2811                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2812                         return -EFAULT;
2813                 if (!nfs_verify_server_address(sap))
2814                         goto out_no_address;
2815                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2816
2817                 if (data->auth_flavourlen) {
2818                         rpc_authflavor_t pseudoflavor;
2819                         if (data->auth_flavourlen > 1)
2820                                 goto out_inval_auth;
2821                         if (copy_from_user(&pseudoflavor,
2822                                            data->auth_flavours,
2823                                            sizeof(pseudoflavor)))
2824                                 return -EFAULT;
2825                         args->selected_flavor = pseudoflavor;
2826                 } else
2827                         args->selected_flavor = RPC_AUTH_UNIX;
2828
2829                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2830                 if (IS_ERR(c))
2831                         return PTR_ERR(c);
2832                 args->nfs_server.hostname = c;
2833
2834                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2835                 if (IS_ERR(c))
2836                         return PTR_ERR(c);
2837                 args->nfs_server.export_path = c;
2838                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2839
2840                 c = strndup_user(data->client_addr.data, 16);
2841                 if (IS_ERR(c))
2842                         return PTR_ERR(c);
2843                 args->client_address = c;
2844
2845                 /*
2846                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2847                  * can deal with.
2848                  */
2849
2850                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2851                 args->rsize     = data->rsize;
2852                 args->wsize     = data->wsize;
2853                 args->timeo     = data->timeo;
2854                 args->retrans   = data->retrans;
2855                 args->acregmin  = data->acregmin;
2856                 args->acregmax  = data->acregmax;
2857                 args->acdirmin  = data->acdirmin;
2858                 args->acdirmax  = data->acdirmax;
2859                 args->nfs_server.protocol = data->proto;
2860                 nfs_validate_transport_protocol(args);
2861                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2862                         goto out_invalid_transport_udp;
2863
2864                 break;
2865         default:
2866                 return NFS_TEXT_DATA;
2867         }
2868
2869         return 0;
2870
2871 out_no_data:
2872         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2873         return -EINVAL;
2874
2875 out_inval_auth:
2876         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2877                  data->auth_flavourlen);
2878         return -EINVAL;
2879
2880 out_no_address:
2881         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2882         return -EINVAL;
2883
2884 out_invalid_transport_udp:
2885         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2886         return -EINVAL;
2887 }
2888
2889 /*
2890  * NFS v4 module parameters need to stay in the
2891  * NFS client for backwards compatibility
2892  */
2893 unsigned int nfs_callback_set_tcpport;
2894 unsigned short nfs_callback_nr_threads;
2895 /* Default cache timeout is 10 minutes */
2896 unsigned int nfs_idmap_cache_timeout = 600;
2897 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2898 bool nfs4_disable_idmapping = true;
2899 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2900 unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE;
2901 unsigned short send_implementation_id = 1;
2902 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2903 bool recover_lost_locks = false;
2904
2905 EXPORT_SYMBOL_GPL(nfs_callback_nr_threads);
2906 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2907 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2908 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2909 EXPORT_SYMBOL_GPL(max_session_slots);
2910 EXPORT_SYMBOL_GPL(max_session_cb_slots);
2911 EXPORT_SYMBOL_GPL(send_implementation_id);
2912 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2913 EXPORT_SYMBOL_GPL(recover_lost_locks);
2914
2915 #define NFS_CALLBACK_MAXPORTNR (65535U)
2916
2917 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2918 {
2919         unsigned long num;
2920         int ret;
2921
2922         if (!val)
2923                 return -EINVAL;
2924         ret = kstrtoul(val, 0, &num);
2925         if (ret || num > NFS_CALLBACK_MAXPORTNR)
2926                 return -EINVAL;
2927         *((unsigned int *)kp->arg) = num;
2928         return 0;
2929 }
2930 static const struct kernel_param_ops param_ops_portnr = {
2931         .set = param_set_portnr,
2932         .get = param_get_uint,
2933 };
2934 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2935
2936 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2937 module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644);
2938 MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be "
2939                 "assigned to the NFSv4 callback channels.");
2940 module_param(nfs_idmap_cache_timeout, int, 0644);
2941 module_param(nfs4_disable_idmapping, bool, 0644);
2942 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2943                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2944 MODULE_PARM_DESC(nfs4_disable_idmapping,
2945                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2946 module_param(max_session_slots, ushort, 0644);
2947 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2948                 "requests the client will negotiate");
2949 module_param(max_session_cb_slots, ushort, 0644);
2950 MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 "
2951                 "callbacks the client will process for a given server");
2952 module_param(send_implementation_id, ushort, 0644);
2953 MODULE_PARM_DESC(send_implementation_id,
2954                 "Send implementation ID with NFSv4.1 exchange_id");
2955 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2956
2957 module_param(recover_lost_locks, bool, 0644);
2958 MODULE_PARM_DESC(recover_lost_locks,
2959                  "If the server reports that a lock might be lost, "
2960                  "try to recover it risking data corruption.");
2961
2962
2963 #endif /* CONFIG_NFS_V4 */