Pileus Git - ~andy/linux/blob - 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/nfs_idmap.h>
  47 #include <linux/vfs.h>
  48 #include <linux/inet.h>
  49 #include <linux/in6.h>
  50 #include <linux/slab.h>
  51 #include <net/ipv6.h>
  52 #include <linux/netdevice.h>
  53 #include <linux/nfs_xdr.h>
  54 #include <linux/magic.h>
  55 #include <linux/parser.h>
  56 #include <linux/nsproxy.h>
  57 #include <linux/rcupdate.h>
  58
  59 #include <asm/uaccess.h>
  60
  61 #include "nfs4_fs.h"
  62 #include "callback.h"
  63 #include "delegation.h"
  64 #include "iostat.h"
  65 #include "internal.h"
  66 #include "fscache.h"
  67 #include "nfs4session.h"
  68 #include "pnfs.h"
  69 #include "nfs.h"
  70
  71 #define NFSDBG_FACILITY         NFSDBG_VFS
  72 #define NFS_TEXT_DATA           1
  73
  74 #if IS_ENABLED(CONFIG_NFS_V3)
  75 #define NFS_DEFAULT_VERSION 3
  76 #else
  77 #define NFS_DEFAULT_VERSION 2
  78 #endif
  79
  80 enum {
  81         /* Mount options that take no arguments */
  82         Opt_soft, Opt_hard,
  83         Opt_posix, Opt_noposix,
  84         Opt_cto, Opt_nocto,
  85         Opt_ac, Opt_noac,
  86         Opt_lock, Opt_nolock,
  87         Opt_udp, Opt_tcp, Opt_rdma,
  88         Opt_acl, Opt_noacl,
  89         Opt_rdirplus, Opt_nordirplus,
  90         Opt_sharecache, Opt_nosharecache,
  91         Opt_resvport, Opt_noresvport,
  92         Opt_fscache, Opt_nofscache,
  93         Opt_migration, Opt_nomigration,
  94
  95         /* Mount options that take integer arguments */
  96         Opt_port,
  97         Opt_rsize, Opt_wsize, Opt_bsize,
  98         Opt_timeo, Opt_retrans,
  99         Opt_acregmin, Opt_acregmax,
 100         Opt_acdirmin, Opt_acdirmax,
 101         Opt_actimeo,
 102         Opt_namelen,
 103         Opt_mountport,
 104         Opt_mountvers,
 105         Opt_minorversion,
 106
 107         /* Mount options that take string arguments */
 108         Opt_nfsvers,
 109         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 110         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 111         Opt_lookupcache,
 112         Opt_fscache_uniq,
 113         Opt_local_lock,
 114
 115         /* Special mount options */
 116         Opt_userspace, Opt_deprecated, Opt_sloppy,
 117
 118         Opt_err
 119 };
 120
 121 static const match_table_t nfs_mount_option_tokens = {
 122         { Opt_userspace, "bg" },
 123         { Opt_userspace, "fg" },
 124         { Opt_userspace, "retry=%s" },
 125
 126         { Opt_sloppy, "sloppy" },
 127
 128         { Opt_soft, "soft" },
 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
 196         Opt_xprt_err
 197 };
 198
 199 static const match_table_t nfs_xprt_protocol_tokens = {
 200         { Opt_xprt_udp, "udp" },
 201         { Opt_xprt_udp6, "udp6" },
 202         { Opt_xprt_tcp, "tcp" },
 203         { Opt_xprt_tcp6, "tcp6" },
 204         { Opt_xprt_rdma, "rdma" },
 205
 206         { Opt_xprt_err, NULL }
 207 };
 208
 209 enum {
 210         Opt_sec_none, Opt_sec_sys,
 211         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 212         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 213         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 214
 215         Opt_sec_err
 216 };
 217
 218 static const match_table_t nfs_secflavor_tokens = {
 219         { Opt_sec_none, "none" },
 220         { Opt_sec_none, "null" },
 221         { Opt_sec_sys, "sys" },
 222
 223         { Opt_sec_krb5, "krb5" },
 224         { Opt_sec_krb5i, "krb5i" },
 225         { Opt_sec_krb5p, "krb5p" },
 226
 227         { Opt_sec_lkey, "lkey" },
 228         { Opt_sec_lkeyi, "lkeyi" },
 229         { Opt_sec_lkeyp, "lkeyp" },
 230
 231         { Opt_sec_spkm, "spkm3" },
 232         { Opt_sec_spkmi, "spkm3i" },
 233         { Opt_sec_spkmp, "spkm3p" },
 234
 235         { Opt_sec_err, NULL }
 236 };
 237
 238 enum {
 239         Opt_lookupcache_all, Opt_lookupcache_positive,
 240         Opt_lookupcache_none,
 241
 242         Opt_lookupcache_err
 243 };
 244
 245 static match_table_t nfs_lookupcache_tokens = {
 246         { Opt_lookupcache_all, "all" },
 247         { Opt_lookupcache_positive, "pos" },
 248         { Opt_lookupcache_positive, "positive" },
 249         { Opt_lookupcache_none, "none" },
 250
 251         { Opt_lookupcache_err, NULL }
 252 };
 253
 254 enum {
 255         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 256         Opt_local_lock_none,
 257
 258         Opt_local_lock_err
 259 };
 260
 261 static match_table_t nfs_local_lock_tokens = {
 262         { Opt_local_lock_all, "all" },
 263         { Opt_local_lock_flock, "flock" },
 264         { Opt_local_lock_posix, "posix" },
 265         { Opt_local_lock_none, "none" },
 266
 267         { Opt_local_lock_err, NULL }
 268 };
 269
 270 enum {
 271         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 272         Opt_vers_4_1,
 273
 274         Opt_vers_err
 275 };
 276
 277 static match_table_t nfs_vers_tokens = {
 278         { Opt_vers_2, "2" },
 279         { Opt_vers_3, "3" },
 280         { Opt_vers_4, "4" },
 281         { Opt_vers_4_0, "4.0" },
 282         { Opt_vers_4_1, "4.1" },
 283
 284         { Opt_vers_err, NULL }
 285 };
 286
 287 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 288                 int flags, const char *dev_name, void *raw_data);
 289
 290 struct file_system_type nfs_fs_type = {
 291         .owner          = THIS_MODULE,
 292         .name           = "nfs",
 293         .mount          = nfs_fs_mount,
 294         .kill_sb        = nfs_kill_super,
 295         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 296 };
 297 MODULE_ALIAS_FS("nfs");
 298 EXPORT_SYMBOL_GPL(nfs_fs_type);
 299
 300 struct file_system_type nfs_xdev_fs_type = {
 301         .owner          = THIS_MODULE,
 302         .name           = "nfs",
 303         .mount          = nfs_xdev_mount,
 304         .kill_sb        = nfs_kill_super,
 305         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 306 };
 307
 308 const struct super_operations nfs_sops = {
 309         .alloc_inode    = nfs_alloc_inode,
 310         .destroy_inode  = nfs_destroy_inode,
 311         .write_inode    = nfs_write_inode,
 312         .drop_inode     = nfs_drop_inode,
 313         .put_super      = nfs_put_super,
 314         .statfs         = nfs_statfs,
 315         .evict_inode    = nfs_evict_inode,
 316         .umount_begin   = nfs_umount_begin,
 317         .show_options   = nfs_show_options,
 318         .show_devname   = nfs_show_devname,
 319         .show_path      = nfs_show_path,
 320         .show_stats     = nfs_show_stats,
 321         .remount_fs     = nfs_remount,
 322 };
 323 EXPORT_SYMBOL_GPL(nfs_sops);
 324
 325 #if IS_ENABLED(CONFIG_NFS_V4)
 326 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 327 static int nfs4_validate_mount_data(void *options,
 328         struct nfs_parsed_mount_data *args, const char *dev_name);
 329
 330 struct file_system_type nfs4_fs_type = {
 331         .owner          = THIS_MODULE,
 332         .name           = "nfs4",
 333         .mount          = nfs_fs_mount,
 334         .kill_sb        = nfs_kill_super,
 335         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 336 };
 337 MODULE_ALIAS_FS("nfs4");
 338 MODULE_ALIAS("nfs4");
 339 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 340
 341 static int __init register_nfs4_fs(void)
 342 {
 343         return register_filesystem(&nfs4_fs_type);
 344 }
 345
 346 static void unregister_nfs4_fs(void)
 347 {
 348         unregister_filesystem(&nfs4_fs_type);
 349 }
 350 #else
 351 static int __init register_nfs4_fs(void)
 352 {
 353         return 0;
 354 }
 355
 356 static void unregister_nfs4_fs(void)
 357 {
 358 }
 359 #endif
 360
 361 static struct shrinker acl_shrinker = {
 362         .shrink         = nfs_access_cache_shrinker,
 363         .seeks          = DEFAULT_SEEKS,
 364 };
 365
 366 /*
 367  * Register the NFS filesystems
 368  */
 369 int __init register_nfs_fs(void)
 370 {
 371         int ret;
 372
 373         ret = register_filesystem(&nfs_fs_type);
 374         if (ret < 0)
 375                 goto error_0;
 376
 377         ret = register_nfs4_fs();
 378         if (ret < 0)
 379                 goto error_1;
 380
 381         ret = nfs_register_sysctl();
 382         if (ret < 0)
 383                 goto error_2;
 384         register_shrinker(&acl_shrinker);
 385         return 0;
 386
 387 error_2:
 388         unregister_nfs4_fs();
 389 error_1:
 390         unregister_filesystem(&nfs_fs_type);
 391 error_0:
 392         return ret;
 393 }
 394
 395 /*
 396  * Unregister the NFS filesystems
 397  */
 398 void __exit unregister_nfs_fs(void)
 399 {
 400         unregister_shrinker(&acl_shrinker);
 401         nfs_unregister_sysctl();
 402         unregister_nfs4_fs();
 403         unregister_filesystem(&nfs_fs_type);
 404 }
 405
 406 void nfs_sb_active(struct super_block *sb)
 407 {
 408         struct nfs_server *server = NFS_SB(sb);
 409
 410         if (atomic_inc_return(&server->active) == 1)
 411                 atomic_inc(&sb->s_active);
 412 }
 413 EXPORT_SYMBOL_GPL(nfs_sb_active);
 414
 415 void nfs_sb_deactive(struct super_block *sb)
 416 {
 417         struct nfs_server *server = NFS_SB(sb);
 418
 419         if (atomic_dec_and_test(&server->active))
 420                 deactivate_super(sb);
 421 }
 422 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 423
 424 /*
 425  * Deliver file system statistics to userspace
 426  */
 427 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 428 {
 429         struct nfs_server *server = NFS_SB(dentry->d_sb);
 430         unsigned char blockbits;
 431         unsigned long blockres;
 432         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 433         struct nfs_fsstat res;
 434         int error = -ENOMEM;
 435
 436         res.fattr = nfs_alloc_fattr();
 437         if (res.fattr == NULL)
 438                 goto out_err;
 439
 440         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 441         if (unlikely(error == -ESTALE)) {
 442                 struct dentry *pd_dentry;
 443
 444                 pd_dentry = dget_parent(dentry);
 445                 if (pd_dentry != NULL) {
 446                         nfs_zap_caches(pd_dentry->d_inode);
 447                         dput(pd_dentry);
 448                 }
 449         }
 450         nfs_free_fattr(res.fattr);
 451         if (error < 0)
 452                 goto out_err;
 453
 454         buf->f_type = NFS_SUPER_MAGIC;
 455
 456         /*
 457          * Current versions of glibc do not correctly handle the
 458          * case where f_frsize != f_bsize.  Eventually we want to
 459          * report the value of wtmult in this field.
 460          */
 461         buf->f_frsize = dentry->d_sb->s_blocksize;
 462
 463         /*
 464          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 465          * are reported in units of f_frsize.  Linux hasn't had
 466          * an f_frsize field in its statfs struct until recently,
 467          * thus historically Linux's sys_statfs reports these
 468          * fields in units of f_bsize.
 469          */
 470         buf->f_bsize = dentry->d_sb->s_blocksize;
 471         blockbits = dentry->d_sb->s_blocksize_bits;
 472         blockres = (1 << blockbits) - 1;
 473         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 474         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 475         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 476
 477         buf->f_files = res.tfiles;
 478         buf->f_ffree = res.afiles;
 479
 480         buf->f_namelen = server->namelen;
 481
 482         return 0;
 483
 484  out_err:
 485         dprintk("%s: statfs error = %d\n", __func__, -error);
 486         return error;
 487 }
 488 EXPORT_SYMBOL_GPL(nfs_statfs);
 489
 490 /*
 491  * Map the security flavour number to a name
 492  */
 493 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 494 {
 495         static const struct {
 496                 rpc_authflavor_t flavour;
 497                 const char *str;
 498         } sec_flavours[] = {
 499                 { RPC_AUTH_NULL, "null" },
 500                 { RPC_AUTH_UNIX, "sys" },
 501                 { RPC_AUTH_GSS_KRB5, "krb5" },
 502                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 503                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 504                 { RPC_AUTH_GSS_LKEY, "lkey" },
 505                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 506                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 507                 { RPC_AUTH_GSS_SPKM, "spkm" },
 508                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 509                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 510                 { UINT_MAX, "unknown" }
 511         };
 512         int i;
 513
 514         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 515                 if (sec_flavours[i].flavour == flavour)
 516                         break;
 517         }
 518         return sec_flavours[i].str;
 519 }
 520
 521 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 522                                   int showdefaults)
 523 {
 524         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 525
 526         seq_printf(m, ",mountproto=");
 527         switch (sap->sa_family) {
 528         case AF_INET:
 529                 switch (nfss->mountd_protocol) {
 530                 case IPPROTO_UDP:
 531                         seq_printf(m, RPCBIND_NETID_UDP);
 532                         break;
 533                 case IPPROTO_TCP:
 534                         seq_printf(m, RPCBIND_NETID_TCP);
 535                         break;
 536                 default:
 537                         if (showdefaults)
 538                                 seq_printf(m, "auto");
 539                 }
 540                 break;
 541         case AF_INET6:
 542                 switch (nfss->mountd_protocol) {
 543                 case IPPROTO_UDP:
 544                         seq_printf(m, RPCBIND_NETID_UDP6);
 545                         break;
 546                 case IPPROTO_TCP:
 547                         seq_printf(m, RPCBIND_NETID_TCP6);
 548                         break;
 549                 default:
 550                         if (showdefaults)
 551                                 seq_printf(m, "auto");
 552                 }
 553                 break;
 554         default:
 555                 if (showdefaults)
 556                         seq_printf(m, "auto");
 557         }
 558 }
 559
 560 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 561                                     int showdefaults)
 562 {
 563         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 564
 565         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 566                 return;
 567
 568         switch (sap->sa_family) {
 569         case AF_INET: {
 570                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 571                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 572                 break;
 573         }
 574         case AF_INET6: {
 575                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 576                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 577                 break;
 578         }
 579         default:
 580                 if (showdefaults)
 581                         seq_printf(m, ",mountaddr=unspecified");
 582         }
 583
 584         if (nfss->mountd_version || showdefaults)
 585                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 586         if ((nfss->mountd_port &&
 587                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 588                 showdefaults)
 589                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 590
 591         nfs_show_mountd_netid(m, nfss, showdefaults);
 592 }
 593
 594 #if IS_ENABLED(CONFIG_NFS_V4)
 595 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 596                                     int showdefaults)
 597 {
 598         struct nfs_client *clp = nfss->nfs_client;
 599
 600         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 601 }
 602 #else
 603 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 604                                     int showdefaults)
 605 {
 606 }
 607 #endif
 608
 609 static void nfs_show_nfs_version(struct seq_file *m,
 610                 unsigned int version,
 611                 unsigned int minorversion)
 612 {
 613         seq_printf(m, ",vers=%u", version);
 614         if (version == 4)
 615                 seq_printf(m, ".%u", minorversion);
 616 }
 617
 618 /*
 619  * Describe the mount options in force on this server representation
 620  */
 621 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 622                                    int showdefaults)
 623 {
 624         static const struct proc_nfs_info {
 625                 int flag;
 626                 const char *str;
 627                 const char *nostr;
 628         } nfs_info[] = {
 629                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 630                 { NFS_MOUNT_POSIX, ",posix", "" },
 631                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 632                 { NFS_MOUNT_NOAC, ",noac", "" },
 633                 { NFS_MOUNT_NONLM, ",nolock", "" },
 634                 { NFS_MOUNT_NOACL, ",noacl", "" },
 635                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 636                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 637                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 638                 { 0, NULL, NULL }
 639         };
 640         const struct proc_nfs_info *nfs_infop;
 641         struct nfs_client *clp = nfss->nfs_client;
 642         u32 version = clp->rpc_ops->version;
 643         int local_flock, local_fcntl;
 644
 645         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 646         seq_printf(m, ",rsize=%u", nfss->rsize);
 647         seq_printf(m, ",wsize=%u", nfss->wsize);
 648         if (nfss->bsize != 0)
 649                 seq_printf(m, ",bsize=%u", nfss->bsize);
 650         seq_printf(m, ",namlen=%u", nfss->namelen);
 651         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 652                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 653         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 654                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 655         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 656                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 657         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 658                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 659         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 660                 if (nfss->flags & nfs_infop->flag)
 661                         seq_puts(m, nfs_infop->str);
 662                 else
 663                         seq_puts(m, nfs_infop->nostr);
 664         }
 665         rcu_read_lock();
 666         seq_printf(m, ",proto=%s",
 667                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 668         rcu_read_unlock();
 669         if (version == 4) {
 670                 if (nfss->port != NFS_PORT)
 671                         seq_printf(m, ",port=%u", nfss->port);
 672         } else
 673                 if (nfss->port)
 674                         seq_printf(m, ",port=%u", nfss->port);
 675
 676         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 677         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 678         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 679
 680         if (version != 4)
 681                 nfs_show_mountd_options(m, nfss, showdefaults);
 682         else
 683                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 684
 685         if (nfss->options & NFS_OPTION_FSCACHE)
 686                 seq_printf(m, ",fsc");
 687
 688         if (nfss->options & NFS_OPTION_MIGRATION)
 689                 seq_printf(m, ",migration");
 690
 691         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 692                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 693                         seq_printf(m, ",lookupcache=none");
 694                 else
 695                         seq_printf(m, ",lookupcache=pos");
 696         }
 697
 698         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 699         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 700
 701         if (!local_flock && !local_fcntl)
 702                 seq_printf(m, ",local_lock=none");
 703         else if (local_flock && local_fcntl)
 704                 seq_printf(m, ",local_lock=all");
 705         else if (local_flock)
 706                 seq_printf(m, ",local_lock=flock");
 707         else
 708                 seq_printf(m, ",local_lock=posix");
 709 }
 710
 711 /*
 712  * Describe the mount options on this VFS mountpoint
 713  */
 714 int nfs_show_options(struct seq_file *m, struct dentry *root)
 715 {
 716         struct nfs_server *nfss = NFS_SB(root->d_sb);
 717
 718         nfs_show_mount_options(m, nfss, 0);
 719
 720         rcu_read_lock();
 721         seq_printf(m, ",addr=%s",
 722                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 723                                                         RPC_DISPLAY_ADDR));
 724         rcu_read_unlock();
 725
 726         return 0;
 727 }
 728 EXPORT_SYMBOL_GPL(nfs_show_options);
 729
 730 #if IS_ENABLED(CONFIG_NFS_V4)
 731 #ifdef CONFIG_NFS_V4_1
 732 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 733 {
 734         if (nfs4_has_session(server->nfs_client))
 735                 seq_printf(m, ",sessions");
 736 }
 737 #else
 738 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 739 #endif
 740 #endif
 741
 742 #ifdef CONFIG_NFS_V4_1
 743 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 744 {
 745         seq_printf(m, ",pnfs=");
 746         if (server->pnfs_curr_ld)
 747                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 748         else
 749                 seq_printf(m, "not configured");
 750 }
 751
 752 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 753 {
 754         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 755                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 756                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 757                            "date='%llu,%u'",
 758                            impl_id->name, impl_id->domain,
 759                            impl_id->date.seconds, impl_id->date.nseconds);
 760         }
 761 }
 762 #else
 763 #if IS_ENABLED(CONFIG_NFS_V4)
 764 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 765 {
 766 }
 767 #endif
 768 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 769 {
 770 }
 771 #endif
 772
 773 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 774 {
 775         char *page = (char *) __get_free_page(GFP_KERNEL);
 776         char *devname, *dummy;
 777         int err = 0;
 778         if (!page)
 779                 return -ENOMEM;
 780         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 781         if (IS_ERR(devname))
 782                 err = PTR_ERR(devname);
 783         else
 784                 seq_escape(m, devname, " \t\n\\");
 785         free_page((unsigned long)page);
 786         return err;
 787 }
 788 EXPORT_SYMBOL_GPL(nfs_show_devname);
 789
 790 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 791 {
 792         seq_puts(m, "/");
 793         return 0;
 794 }
 795 EXPORT_SYMBOL_GPL(nfs_show_path);
 796
 797 /*
 798  * Present statistical information for this VFS mountpoint
 799  */
 800 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 801 {
 802         int i, cpu;
 803         struct nfs_server *nfss = NFS_SB(root->d_sb);
 804         struct rpc_auth *auth = nfss->client->cl_auth;
 805         struct nfs_iostats totals = { };
 806
 807         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 808
 809         /*
 810          * Display all mount option settings
 811          */
 812         seq_printf(m, "\n\topts:\t");
 813         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 814         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 815         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 816         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 817         nfs_show_mount_options(m, nfss, 1);
 818
 819         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 820
 821         show_implementation_id(m, nfss);
 822
 823         seq_printf(m, "\n\tcaps:\t");
 824         seq_printf(m, "caps=0x%x", nfss->caps);
 825         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 826         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 827         seq_printf(m, ",bsize=%u", nfss->bsize);
 828         seq_printf(m, ",namlen=%u", nfss->namelen);
 829
 830 #if IS_ENABLED(CONFIG_NFS_V4)
 831         if (nfss->nfs_client->rpc_ops->version == 4) {
 832                 seq_printf(m, "\n\tnfsv4:\t");
 833                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 834                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 835                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 836                 show_sessions(m, nfss);
 837                 show_pnfs(m, nfss);
 838         }
 839 #endif
 840
 841         /*
 842          * Display security flavor in effect for this mount
 843          */
 844         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 845         if (auth->au_flavor)
 846                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 847
 848         /*
 849          * Display superblock I/O counters
 850          */
 851         for_each_possible_cpu(cpu) {
 852                 struct nfs_iostats *stats;
 853
 854                 preempt_disable();
 855                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 856
 857                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 858                         totals.events[i] += stats->events[i];
 859                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 860                         totals.bytes[i] += stats->bytes[i];
 861 #ifdef CONFIG_NFS_FSCACHE
 862                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 863                         totals.fscache[i] += stats->fscache[i];
 864 #endif
 865
 866                 preempt_enable();
 867         }
 868
 869         seq_printf(m, "\n\tevents:\t");
 870         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 871                 seq_printf(m, "%lu ", totals.events[i]);
 872         seq_printf(m, "\n\tbytes:\t");
 873         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 874                 seq_printf(m, "%Lu ", totals.bytes[i]);
 875 #ifdef CONFIG_NFS_FSCACHE
 876         if (nfss->options & NFS_OPTION_FSCACHE) {
 877                 seq_printf(m, "\n\tfsc:\t");
 878                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 879                         seq_printf(m, "%Lu ", totals.bytes[i]);
 880         }
 881 #endif
 882         seq_printf(m, "\n");
 883
 884         rpc_print_iostats(m, nfss->client);
 885
 886         return 0;
 887 }
 888 EXPORT_SYMBOL_GPL(nfs_show_stats);
 889
 890 /*
 891  * Begin unmount by attempting to remove all automounted mountpoints we added
 892  * in response to xdev traversals and referrals
 893  */
 894 void nfs_umount_begin(struct super_block *sb)
 895 {
 896         struct nfs_server *server;
 897         struct rpc_clnt *rpc;
 898
 899         server = NFS_SB(sb);
 900         /* -EIO all pending I/O */
 901         rpc = server->client_acl;
 902         if (!IS_ERR(rpc))
 903                 rpc_killall_tasks(rpc);
 904         rpc = server->client;
 905         if (!IS_ERR(rpc))
 906                 rpc_killall_tasks(rpc);
 907 }
 908 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 909
 910 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 911 {
 912         struct nfs_parsed_mount_data *data;
 913
 914         data = kzalloc(sizeof(*data), GFP_KERNEL);
 915         if (data) {
 916                 data->acregmin          = NFS_DEF_ACREGMIN;
 917                 data->acregmax          = NFS_DEF_ACREGMAX;
 918                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 919                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 920                 data->mount_server.port = NFS_UNSPEC_PORT;
 921                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 922                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 923                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 924                 data->auth_flavor_len   = 1;
 925                 data->minorversion      = 0;
 926                 data->need_mount        = true;
 927                 data->net               = current->nsproxy->net_ns;
 928                 security_init_mnt_opts(&data->lsm_opts);
 929         }
 930         return data;
 931 }
 932
 933 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 934 {
 935         if (data) {
 936                 kfree(data->client_address);
 937                 kfree(data->mount_server.hostname);
 938                 kfree(data->nfs_server.export_path);
 939                 kfree(data->nfs_server.hostname);
 940                 kfree(data->fscache_uniq);
 941                 security_free_mnt_opts(&data->lsm_opts);
 942                 kfree(data);
 943         }
 944 }
 945
 946 /*
 947  * Sanity-check a server address provided by the mount command.
 948  *
 949  * Address family must be initialized, and address must not be
 950  * the ANY address for that family.
 951  */
 952 static int nfs_verify_server_address(struct sockaddr *addr)
 953 {
 954         switch (addr->sa_family) {
 955         case AF_INET: {
 956                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 957                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 958         }
 959         case AF_INET6: {
 960                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 961                 return !ipv6_addr_any(sa);
 962         }
 963         }
 964
 965         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 966         return 0;
 967 }
 968
 969 /*
 970  * Select between a default port value and a user-specified port value.
 971  * If a zero value is set, then autobind will be used.
 972  */
 973 static void nfs_set_port(struct sockaddr *sap, int *port,
 974                                  const unsigned short default_port)
 975 {
 976         if (*port == NFS_UNSPEC_PORT)
 977                 *port = default_port;
 978
 979         rpc_set_port(sap, *port);
 980 }
 981
 982 /*
 983  * Sanity check the NFS transport protocol.
 984  *
 985  */
 986 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 987 {
 988         switch (mnt->nfs_server.protocol) {
 989         case XPRT_TRANSPORT_UDP:
 990         case XPRT_TRANSPORT_TCP:
 991         case XPRT_TRANSPORT_RDMA:
 992                 break;
 993         default:
 994                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 995         }
 996 }
 997
 998 /*
 999  * For text based NFSv2/v3 mounts, the mount protocol transport default
1000  * settings should depend upon the specified NFS transport.
1001  */
1002 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1003 {
1004         nfs_validate_transport_protocol(mnt);
1005
1006         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1007             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1008                         return;
1009         switch (mnt->nfs_server.protocol) {
1010         case XPRT_TRANSPORT_UDP:
1011                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1012                 break;
1013         case XPRT_TRANSPORT_TCP:
1014         case XPRT_TRANSPORT_RDMA:
1015                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1016         }
1017 }
1018
1019 /*
1020  * Parse the value of the 'sec=' option.
1021  */
1022 static int nfs_parse_security_flavors(char *value,
1023                                       struct nfs_parsed_mount_data *mnt)
1024 {
1025         substring_t args[MAX_OPT_ARGS];
1026
1027         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1028
1029         switch (match_token(value, nfs_secflavor_tokens, args)) {
1030         case Opt_sec_none:
1031                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1032                 break;
1033         case Opt_sec_sys:
1034                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1035                 break;
1036         case Opt_sec_krb5:
1037                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1038                 break;
1039         case Opt_sec_krb5i:
1040                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1041                 break;
1042         case Opt_sec_krb5p:
1043                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1044                 break;
1045         case Opt_sec_lkey:
1046                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1047                 break;
1048         case Opt_sec_lkeyi:
1049                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1050                 break;
1051         case Opt_sec_lkeyp:
1052                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1053                 break;
1054         case Opt_sec_spkm:
1055                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1056                 break;
1057         case Opt_sec_spkmi:
1058                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1059                 break;
1060         case Opt_sec_spkmp:
1061                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1062                 break;
1063         default:
1064                 return 0;
1065         }
1066
1067         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1068         mnt->auth_flavor_len = 1;
1069         return 1;
1070 }
1071
1072 static int nfs_parse_version_string(char *string,
1073                 struct nfs_parsed_mount_data *mnt,
1074                 substring_t *args)
1075 {
1076         mnt->flags &= ~NFS_MOUNT_VER3;
1077         switch (match_token(string, nfs_vers_tokens, args)) {
1078         case Opt_vers_2:
1079                 mnt->version = 2;
1080                 break;
1081         case Opt_vers_3:
1082                 mnt->flags |= NFS_MOUNT_VER3;
1083                 mnt->version = 3;
1084                 break;
1085         case Opt_vers_4:
1086                 /* Backward compatibility option. In future,
1087                  * the mount program should always supply
1088                  * a NFSv4 minor version number.
1089                  */
1090                 mnt->version = 4;
1091                 break;
1092         case Opt_vers_4_0:
1093                 mnt->version = 4;
1094                 mnt->minorversion = 0;
1095                 break;
1096         case Opt_vers_4_1:
1097                 mnt->version = 4;
1098                 mnt->minorversion = 1;
1099                 break;
1100         default:
1101                 return 0;
1102         }
1103         return 1;
1104 }
1105
1106 static int nfs_get_option_str(substring_t args[], char **option)
1107 {
1108         kfree(*option);
1109         *option = match_strdup(args);
1110         return !*option;
1111 }
1112
1113 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1114 {
1115         int rc;
1116         char *string;
1117
1118         string = match_strdup(args);
1119         if (string == NULL)
1120                 return -ENOMEM;
1121         rc = kstrtoul(string, 10, option);
1122         kfree(string);
1123
1124         return rc;
1125 }
1126
1127 /*
1128  * Error-check and convert a string of mount options from user space into
1129  * a data structure.  The whole mount string is processed; bad options are
1130  * skipped as they are encountered.  If there were no errors, return 1;
1131  * otherwise return 0 (zero).
1132  */
1133 static int nfs_parse_mount_options(char *raw,
1134                                    struct nfs_parsed_mount_data *mnt)
1135 {
1136         char *p, *string, *secdata;
1137         int rc, sloppy = 0, invalid_option = 0;
1138         unsigned short protofamily = AF_UNSPEC;
1139         unsigned short mountfamily = AF_UNSPEC;
1140
1141         if (!raw) {
1142                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1143                 return 1;
1144         }
1145         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1146
1147         secdata = alloc_secdata();
1148         if (!secdata)
1149                 goto out_nomem;
1150
1151         rc = security_sb_copy_data(raw, secdata);
1152         if (rc)
1153                 goto out_security_failure;
1154
1155         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1156         if (rc)
1157                 goto out_security_failure;
1158
1159         free_secdata(secdata);
1160
1161         while ((p = strsep(&raw, ",")) != NULL) {
1162                 substring_t args[MAX_OPT_ARGS];
1163                 unsigned long option;
1164                 int token;
1165
1166                 if (!*p)
1167                         continue;
1168
1169                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1170
1171                 token = match_token(p, nfs_mount_option_tokens, args);
1172                 switch (token) {
1173
1174                 /*
1175                  * boolean options:  foo/nofoo
1176                  */
1177                 case Opt_soft:
1178                         mnt->flags |= NFS_MOUNT_SOFT;
1179                         break;
1180                 case Opt_hard:
1181                         mnt->flags &= ~NFS_MOUNT_SOFT;
1182                         break;
1183                 case Opt_posix:
1184                         mnt->flags |= NFS_MOUNT_POSIX;
1185                         break;
1186                 case Opt_noposix:
1187                         mnt->flags &= ~NFS_MOUNT_POSIX;
1188                         break;
1189                 case Opt_cto:
1190                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1191                         break;
1192                 case Opt_nocto:
1193                         mnt->flags |= NFS_MOUNT_NOCTO;
1194                         break;
1195                 case Opt_ac:
1196                         mnt->flags &= ~NFS_MOUNT_NOAC;
1197                         break;
1198                 case Opt_noac:
1199                         mnt->flags |= NFS_MOUNT_NOAC;
1200                         break;
1201                 case Opt_lock:
1202                         mnt->flags &= ~NFS_MOUNT_NONLM;
1203                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1204                                         NFS_MOUNT_LOCAL_FCNTL);
1205                         break;
1206                 case Opt_nolock:
1207                         mnt->flags |= NFS_MOUNT_NONLM;
1208                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1209                                        NFS_MOUNT_LOCAL_FCNTL);
1210                         break;
1211                 case Opt_udp:
1212                         mnt->flags &= ~NFS_MOUNT_TCP;
1213                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1214                         break;
1215                 case Opt_tcp:
1216                         mnt->flags |= NFS_MOUNT_TCP;
1217                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1218                         break;
1219                 case Opt_rdma:
1220                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1221                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1222                         xprt_load_transport(p);
1223                         break;
1224                 case Opt_acl:
1225                         mnt->flags &= ~NFS_MOUNT_NOACL;
1226                         break;
1227                 case Opt_noacl:
1228                         mnt->flags |= NFS_MOUNT_NOACL;
1229                         break;
1230                 case Opt_rdirplus:
1231                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1232                         break;
1233                 case Opt_nordirplus:
1234                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1235                         break;
1236                 case Opt_sharecache:
1237                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1238                         break;
1239                 case Opt_nosharecache:
1240                         mnt->flags |= NFS_MOUNT_UNSHARED;
1241                         break;
1242                 case Opt_resvport:
1243                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1244                         break;
1245                 case Opt_noresvport:
1246                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1247                         break;
1248                 case Opt_fscache:
1249                         mnt->options |= NFS_OPTION_FSCACHE;
1250                         kfree(mnt->fscache_uniq);
1251                         mnt->fscache_uniq = NULL;
1252                         break;
1253                 case Opt_nofscache:
1254                         mnt->options &= ~NFS_OPTION_FSCACHE;
1255                         kfree(mnt->fscache_uniq);
1256                         mnt->fscache_uniq = NULL;
1257                         break;
1258                 case Opt_migration:
1259                         mnt->options |= NFS_OPTION_MIGRATION;
1260                         break;
1261                 case Opt_nomigration:
1262                         mnt->options &= NFS_OPTION_MIGRATION;
1263                         break;
1264
1265                 /*
1266                  * options that take numeric values
1267                  */
1268                 case Opt_port:
1269                         if (nfs_get_option_ul(args, &option) ||
1270                             option > USHRT_MAX)
1271                                 goto out_invalid_value;
1272                         mnt->nfs_server.port = option;
1273                         break;
1274                 case Opt_rsize:
1275                         if (nfs_get_option_ul(args, &option))
1276                                 goto out_invalid_value;
1277                         mnt->rsize = option;
1278                         break;
1279                 case Opt_wsize:
1280                         if (nfs_get_option_ul(args, &option))
1281                                 goto out_invalid_value;
1282                         mnt->wsize = option;
1283                         break;
1284                 case Opt_bsize:
1285                         if (nfs_get_option_ul(args, &option))
1286                                 goto out_invalid_value;
1287                         mnt->bsize = option;
1288                         break;
1289                 case Opt_timeo:
1290                         if (nfs_get_option_ul(args, &option) || option == 0)
1291                                 goto out_invalid_value;
1292                         mnt->timeo = option;
1293                         break;
1294                 case Opt_retrans:
1295                         if (nfs_get_option_ul(args, &option) || option == 0)
1296                                 goto out_invalid_value;
1297                         mnt->retrans = option;
1298                         break;
1299                 case Opt_acregmin:
1300                         if (nfs_get_option_ul(args, &option))
1301                                 goto out_invalid_value;
1302                         mnt->acregmin = option;
1303                         break;
1304                 case Opt_acregmax:
1305                         if (nfs_get_option_ul(args, &option))
1306                                 goto out_invalid_value;
1307                         mnt->acregmax = option;
1308                         break;
1309                 case Opt_acdirmin:
1310                         if (nfs_get_option_ul(args, &option))
1311                                 goto out_invalid_value;
1312                         mnt->acdirmin = option;
1313                         break;
1314                 case Opt_acdirmax:
1315                         if (nfs_get_option_ul(args, &option))
1316                                 goto out_invalid_value;
1317                         mnt->acdirmax = option;
1318                         break;
1319                 case Opt_actimeo:
1320                         if (nfs_get_option_ul(args, &option))
1321                                 goto out_invalid_value;
1322                         mnt->acregmin = mnt->acregmax =
1323                         mnt->acdirmin = mnt->acdirmax = option;
1324                         break;
1325                 case Opt_namelen:
1326                         if (nfs_get_option_ul(args, &option))
1327                                 goto out_invalid_value;
1328                         mnt->namlen = option;
1329                         break;
1330                 case Opt_mountport:
1331                         if (nfs_get_option_ul(args, &option) ||
1332                             option > USHRT_MAX)
1333                                 goto out_invalid_value;
1334                         mnt->mount_server.port = option;
1335                         break;
1336                 case Opt_mountvers:
1337                         if (nfs_get_option_ul(args, &option) ||
1338                             option < NFS_MNT_VERSION ||
1339                             option > NFS_MNT3_VERSION)
1340                                 goto out_invalid_value;
1341                         mnt->mount_server.version = option;
1342                         break;
1343                 case Opt_minorversion:
1344                         if (nfs_get_option_ul(args, &option))
1345                                 goto out_invalid_value;
1346                         if (option > NFS4_MAX_MINOR_VERSION)
1347                                 goto out_invalid_value;
1348                         mnt->minorversion = option;
1349                         break;
1350
1351                 /*
1352                  * options that take text values
1353                  */
1354                 case Opt_nfsvers:
1355                         string = match_strdup(args);
1356                         if (string == NULL)
1357                                 goto out_nomem;
1358                         rc = nfs_parse_version_string(string, mnt, args);
1359                         kfree(string);
1360                         if (!rc)
1361                                 goto out_invalid_value;
1362                         break;
1363                 case Opt_sec:
1364                         string = match_strdup(args);
1365                         if (string == NULL)
1366                                 goto out_nomem;
1367                         rc = nfs_parse_security_flavors(string, mnt);
1368                         kfree(string);
1369                         if (!rc) {
1370                                 dfprintk(MOUNT, "NFS:   unrecognized "
1371                                                 "security flavor\n");
1372                                 return 0;
1373                         }
1374                         break;
1375                 case Opt_proto:
1376                         string = match_strdup(args);
1377                         if (string == NULL)
1378                                 goto out_nomem;
1379                         token = match_token(string,
1380                                             nfs_xprt_protocol_tokens, args);
1381
1382                         protofamily = AF_INET;
1383                         switch (token) {
1384                         case Opt_xprt_udp6:
1385                                 protofamily = AF_INET6;
1386                         case Opt_xprt_udp:
1387                                 mnt->flags &= ~NFS_MOUNT_TCP;
1388                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1389                                 break;
1390                         case Opt_xprt_tcp6:
1391                                 protofamily = AF_INET6;
1392                         case Opt_xprt_tcp:
1393                                 mnt->flags |= NFS_MOUNT_TCP;
1394                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1395                                 break;
1396                         case Opt_xprt_rdma:
1397                                 /* vector side protocols to TCP */
1398                                 mnt->flags |= NFS_MOUNT_TCP;
1399                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1400                                 xprt_load_transport(string);
1401                                 break;
1402                         default:
1403                                 dfprintk(MOUNT, "NFS:   unrecognized "
1404                                                 "transport protocol\n");
1405                                 kfree(string);
1406                                 return 0;
1407                         }
1408                         kfree(string);
1409                         break;
1410                 case Opt_mountproto:
1411                         string = match_strdup(args);
1412                         if (string == NULL)
1413                                 goto out_nomem;
1414                         token = match_token(string,
1415                                             nfs_xprt_protocol_tokens, args);
1416                         kfree(string);
1417
1418                         mountfamily = AF_INET;
1419                         switch (token) {
1420                         case Opt_xprt_udp6:
1421                                 mountfamily = AF_INET6;
1422                         case Opt_xprt_udp:
1423                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1424                                 break;
1425                         case Opt_xprt_tcp6:
1426                                 mountfamily = AF_INET6;
1427                         case Opt_xprt_tcp:
1428                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1429                                 break;
1430                         case Opt_xprt_rdma: /* not used for side protocols */
1431                         default:
1432                                 dfprintk(MOUNT, "NFS:   unrecognized "
1433                                                 "transport protocol\n");
1434                                 return 0;
1435                         }
1436                         break;
1437                 case Opt_addr:
1438                         string = match_strdup(args);
1439                         if (string == NULL)
1440                                 goto out_nomem;
1441                         mnt->nfs_server.addrlen =
1442                                 rpc_pton(mnt->net, string, strlen(string),
1443                                         (struct sockaddr *)
1444                                         &mnt->nfs_server.address,
1445                                         sizeof(mnt->nfs_server.address));
1446                         kfree(string);
1447                         if (mnt->nfs_server.addrlen == 0)
1448                                 goto out_invalid_address;
1449                         break;
1450                 case Opt_clientaddr:
1451                         if (nfs_get_option_str(args, &mnt->client_address))
1452                                 goto out_nomem;
1453                         break;
1454                 case Opt_mounthost:
1455                         if (nfs_get_option_str(args,
1456                                                &mnt->mount_server.hostname))
1457                                 goto out_nomem;
1458                         break;
1459                 case Opt_mountaddr:
1460                         string = match_strdup(args);
1461                         if (string == NULL)
1462                                 goto out_nomem;
1463                         mnt->mount_server.addrlen =
1464                                 rpc_pton(mnt->net, string, strlen(string),
1465                                         (struct sockaddr *)
1466                                         &mnt->mount_server.address,
1467                                         sizeof(mnt->mount_server.address));
1468                         kfree(string);
1469                         if (mnt->mount_server.addrlen == 0)
1470                                 goto out_invalid_address;
1471                         break;
1472                 case Opt_lookupcache:
1473                         string = match_strdup(args);
1474                         if (string == NULL)
1475                                 goto out_nomem;
1476                         token = match_token(string,
1477                                         nfs_lookupcache_tokens, args);
1478                         kfree(string);
1479                         switch (token) {
1480                                 case Opt_lookupcache_all:
1481                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1482                                         break;
1483                                 case Opt_lookupcache_positive:
1484                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1485                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1486                                         break;
1487                                 case Opt_lookupcache_none:
1488                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1489                                         break;
1490                                 default:
1491                                         dfprintk(MOUNT, "NFS:   invalid "
1492                                                         "lookupcache argument\n");
1493                                         return 0;
1494                         };
1495                         break;
1496                 case Opt_fscache_uniq:
1497                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1498                                 goto out_nomem;
1499                         mnt->options |= NFS_OPTION_FSCACHE;
1500                         break;
1501                 case Opt_local_lock:
1502                         string = match_strdup(args);
1503                         if (string == NULL)
1504                                 goto out_nomem;
1505                         token = match_token(string, nfs_local_lock_tokens,
1506                                         args);
1507                         kfree(string);
1508                         switch (token) {
1509                         case Opt_local_lock_all:
1510                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1511                                                NFS_MOUNT_LOCAL_FCNTL);
1512                                 break;
1513                         case Opt_local_lock_flock:
1514                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1515                                 break;
1516                         case Opt_local_lock_posix:
1517                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1518                                 break;
1519                         case Opt_local_lock_none:
1520                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1521                                                 NFS_MOUNT_LOCAL_FCNTL);
1522                                 break;
1523                         default:
1524                                 dfprintk(MOUNT, "NFS:   invalid "
1525                                                 "local_lock argument\n");
1526                                 return 0;
1527                         };
1528                         break;
1529
1530                 /*
1531                  * Special options
1532                  */
1533                 case Opt_sloppy:
1534                         sloppy = 1;
1535                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1536                         break;
1537                 case Opt_userspace:
1538                 case Opt_deprecated:
1539                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1540                                         "'%s'\n", p);
1541                         break;
1542
1543                 default:
1544                         invalid_option = 1;
1545                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1546                                         "'%s'\n", p);
1547                 }
1548         }
1549
1550         if (!sloppy && invalid_option)
1551                 return 0;
1552
1553         if (mnt->minorversion && mnt->version != 4)
1554                 goto out_minorversion_mismatch;
1555
1556         if (mnt->options & NFS_OPTION_MIGRATION &&
1557             mnt->version != 4 && mnt->minorversion != 0)
1558                 goto out_migration_misuse;
1559
1560         /*
1561          * verify that any proto=/mountproto= options match the address
1562          * families in the addr=/mountaddr= options.
1563          */
1564         if (protofamily != AF_UNSPEC &&
1565             protofamily != mnt->nfs_server.address.ss_family)
1566                 goto out_proto_mismatch;
1567
1568         if (mountfamily != AF_UNSPEC) {
1569                 if (mnt->mount_server.addrlen) {
1570                         if (mountfamily != mnt->mount_server.address.ss_family)
1571                                 goto out_mountproto_mismatch;
1572                 } else {
1573                         if (mountfamily != mnt->nfs_server.address.ss_family)
1574                                 goto out_mountproto_mismatch;
1575                 }
1576         }
1577
1578         return 1;
1579
1580 out_mountproto_mismatch:
1581         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1582                          "option\n");
1583         return 0;
1584 out_proto_mismatch:
1585         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1586         return 0;
1587 out_invalid_address:
1588         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1589         return 0;
1590 out_invalid_value:
1591         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1592         return 0;
1593 out_minorversion_mismatch:
1594         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1595                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1596         return 0;
1597 out_migration_misuse:
1598         printk(KERN_INFO
1599                 "NFS: 'migration' not supported for this NFS version\n");
1600         return 0;
1601 out_nomem:
1602         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1603         return 0;
1604 out_security_failure:
1605         free_secdata(secdata);
1606         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1607         return 0;
1608 }
1609
1610 /*
1611  * Match the requested auth flavors with the list returned by
1612  * the server.  Returns zero and sets the mount's authentication
1613  * flavor on success; returns -EACCES if server does not support
1614  * the requested flavor.
1615  */
1616 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1617                              struct nfs_mount_request *request)
1618 {
1619         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1620
1621         /*
1622          * Certain releases of Linux's mountd return an empty
1623          * flavor list.  To prevent behavioral regression with
1624          * these servers (ie. rejecting mounts that used to
1625          * succeed), revert to pre-2.6.32 behavior (no checking)
1626          * if the returned flavor list is empty.
1627          */
1628         if (server_authlist_len == 0)
1629                 return 0;
1630
1631         /*
1632          * We avoid sophisticated negotiating here, as there are
1633          * plenty of cases where we can get it wrong, providing
1634          * either too little or too much security.
1635          *
1636          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1637          * flavor listed first.  However, some servers list
1638          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1639          * preferred default, in args->auth_flavors[0] if user
1640          * didn't specify sec= mount option.
1641          */
1642         for (i = 0; i < args->auth_flavor_len; i++)
1643                 for (j = 0; j < server_authlist_len; j++)
1644                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1645                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1646                                         request->auth_flavs[j]);
1647                                 args->auth_flavors[0] = request->auth_flavs[j];
1648                                 return 0;
1649                         }
1650
1651         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1652         nfs_umount(request);
1653         return -EACCES;
1654 }
1655
1656 /*
1657  * Use the remote server's MOUNT service to request the NFS file handle
1658  * corresponding to the provided path.
1659  */
1660 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1661                              struct nfs_fh *root_fh)
1662 {
1663         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1664         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1665         struct nfs_mount_request request = {
1666                 .sap            = (struct sockaddr *)
1667                                                 &args->mount_server.address,
1668                 .dirpath        = args->nfs_server.export_path,
1669                 .protocol       = args->mount_server.protocol,
1670                 .fh             = root_fh,
1671                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1672                 .auth_flav_len  = &server_authlist_len,
1673                 .auth_flavs     = server_authlist,
1674                 .net            = args->net,
1675         };
1676         int status;
1677
1678         if (args->mount_server.version == 0) {
1679                 switch (args->version) {
1680                         default:
1681                                 args->mount_server.version = NFS_MNT3_VERSION;
1682                                 break;
1683                         case 2:
1684                                 args->mount_server.version = NFS_MNT_VERSION;
1685                 }
1686         }
1687         request.version = args->mount_server.version;
1688
1689         if (args->mount_server.hostname)
1690                 request.hostname = args->mount_server.hostname;
1691         else
1692                 request.hostname = args->nfs_server.hostname;
1693
1694         /*
1695          * Construct the mount server's address.
1696          */
1697         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1698                 memcpy(request.sap, &args->nfs_server.address,
1699                        args->nfs_server.addrlen);
1700                 args->mount_server.addrlen = args->nfs_server.addrlen;
1701         }
1702         request.salen = args->mount_server.addrlen;
1703         nfs_set_port(request.sap, &args->mount_server.port, 0);
1704
1705         /*
1706          * Now ask the mount server to map our export path
1707          * to a file handle.
1708          */
1709         status = nfs_mount(&request);
1710         if (status != 0) {
1711                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1712                                 request.hostname, status);
1713                 return status;
1714         }
1715
1716         /*
1717          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1718          */
1719         if (args->mount_server.version != NFS_MNT3_VERSION)
1720                 return 0;
1721         return nfs_walk_authlist(args, &request);
1722 }
1723
1724 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1725                              struct nfs_mount_info *mount_info,
1726                              struct nfs_subversion *nfs_mod)
1727 {
1728         int status;
1729         struct nfs_server *server;
1730
1731         if (mount_info->parsed->need_mount) {
1732                 status = nfs_request_mount(mount_info->parsed, mount_info->mntfh);
1733                 if (status)
1734                         return ERR_PTR(status);
1735         }
1736
1737         /* Get a volume representation */
1738         server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1739         if (IS_ERR(server))
1740                 return ERR_CAST(server);
1741
1742         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1743 }
1744 EXPORT_SYMBOL_GPL(nfs_try_mount);
1745
1746 /*
1747  * Split "dev_name" into "hostname:export_path".
1748  *
1749  * The leftmost colon demarks the split between the server's hostname
1750  * and the export path.  If the hostname starts with a left square
1751  * bracket, then it may contain colons.
1752  *
1753  * Note: caller frees hostname and export path, even on error.
1754  */
1755 static int nfs_parse_devname(const char *dev_name,
1756                              char **hostname, size_t maxnamlen,
1757                              char **export_path, size_t maxpathlen)
1758 {
1759         size_t len;
1760         char *end;
1761
1762         /* Is the host name protected with square brakcets? */
1763         if (*dev_name == '[') {
1764                 end = strchr(++dev_name, ']');
1765                 if (end == NULL || end[1] != ':')
1766                         goto out_bad_devname;
1767
1768                 len = end - dev_name;
1769                 end++;
1770         } else {
1771                 char *comma;
1772
1773                 end = strchr(dev_name, ':');
1774                 if (end == NULL)
1775                         goto out_bad_devname;
1776                 len = end - dev_name;
1777
1778                 /* kill possible hostname list: not supported */
1779                 comma = strchr(dev_name, ',');
1780                 if (comma != NULL && comma < end)
1781                         *comma = 0;
1782         }
1783
1784         if (len > maxnamlen)
1785                 goto out_hostname;
1786
1787         /* N.B. caller will free nfs_server.hostname in all cases */
1788         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1789         if (*hostname == NULL)
1790                 goto out_nomem;
1791         len = strlen(++end);
1792         if (len > maxpathlen)
1793                 goto out_path;
1794         *export_path = kstrndup(end, len, GFP_KERNEL);
1795         if (!*export_path)
1796                 goto out_nomem;
1797
1798         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1799         return 0;
1800
1801 out_bad_devname:
1802         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1803         return -EINVAL;
1804
1805 out_nomem:
1806         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1807         return -ENOMEM;
1808
1809 out_hostname:
1810         dfprintk(MOUNT, "NFS: server hostname too long\n");
1811         return -ENAMETOOLONG;
1812
1813 out_path:
1814         dfprintk(MOUNT, "NFS: export pathname too long\n");
1815         return -ENAMETOOLONG;
1816 }
1817
1818 /*
1819  * Validate the NFS2/NFS3 mount data
1820  * - fills in the mount root filehandle
1821  *
1822  * For option strings, user space handles the following behaviors:
1823  *
1824  * + DNS: mapping server host name to IP address ("addr=" option)
1825  *
1826  * + failure mode: how to behave if a mount request can't be handled
1827  *   immediately ("fg/bg" option)
1828  *
1829  * + retry: how often to retry a mount request ("retry=" option)
1830  *
1831  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1832  *   mountproto=tcp after mountproto=udp, and so on
1833  */
1834 static int nfs23_validate_mount_data(void *options,
1835                                      struct nfs_parsed_mount_data *args,
1836                                      struct nfs_fh *mntfh,
1837                                      const char *dev_name)
1838 {
1839         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1840         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1841
1842         if (data == NULL)
1843                 goto out_no_data;
1844
1845         args->version = NFS_DEFAULT_VERSION;
1846         switch (data->version) {
1847         case 1:
1848                 data->namlen = 0;
1849         case 2:
1850                 data->bsize = 0;
1851         case 3:
1852                 if (data->flags & NFS_MOUNT_VER3)
1853                         goto out_no_v3;
1854                 data->root.size = NFS2_FHSIZE;
1855                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1856         case 4:
1857                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1858                         goto out_no_sec;
1859         case 5:
1860                 memset(data->context, 0, sizeof(data->context));
1861         case 6:
1862                 if (data->flags & NFS_MOUNT_VER3) {
1863                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1864                                 goto out_invalid_fh;
1865                         mntfh->size = data->root.size;
1866                         args->version = 3;
1867                 } else {
1868                         mntfh->size = NFS2_FHSIZE;
1869                         args->version = 2;
1870                 }
1871
1872
1873                 memcpy(mntfh->data, data->root.data, mntfh->size);
1874                 if (mntfh->size < sizeof(mntfh->data))
1875                         memset(mntfh->data + mntfh->size, 0,
1876                                sizeof(mntfh->data) - mntfh->size);
1877
1878                 /*
1879                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1880                  * can deal with.
1881                  */
1882                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1883                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1884                 args->rsize             = data->rsize;
1885                 args->wsize             = data->wsize;
1886                 args->timeo             = data->timeo;
1887                 args->retrans           = data->retrans;
1888                 args->acregmin          = data->acregmin;
1889                 args->acregmax          = data->acregmax;
1890                 args->acdirmin          = data->acdirmin;
1891                 args->acdirmax          = data->acdirmax;
1892                 args->need_mount        = false;
1893
1894                 memcpy(sap, &data->addr, sizeof(data->addr));
1895                 args->nfs_server.addrlen = sizeof(data->addr);
1896                 args->nfs_server.port = ntohs(data->addr.sin_port);
1897                 if (!nfs_verify_server_address(sap))
1898                         goto out_no_address;
1899
1900                 if (!(data->flags & NFS_MOUNT_TCP))
1901                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1902                 /* N.B. caller will free nfs_server.hostname in all cases */
1903                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1904                 args->namlen            = data->namlen;
1905                 args->bsize             = data->bsize;
1906
1907                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1908                         args->auth_flavors[0] = data->pseudoflavor;
1909                 if (!args->nfs_server.hostname)
1910                         goto out_nomem;
1911
1912                 if (!(data->flags & NFS_MOUNT_NONLM))
1913                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1914                                          NFS_MOUNT_LOCAL_FCNTL);
1915                 else
1916                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1917                                         NFS_MOUNT_LOCAL_FCNTL);
1918                 /*
1919                  * The legacy version 6 binary mount data from userspace has a
1920                  * field used only to transport selinux information into the
1921                  * the kernel.  To continue to support that functionality we
1922                  * have a touch of selinux knowledge here in the NFS code. The
1923                  * userspace code converted context=blah to just blah so we are
1924                  * converting back to the full string selinux understands.
1925                  */
1926                 if (data->context[0]){
1927 #ifdef CONFIG_SECURITY_SELINUX
1928                         int rc;
1929                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1930                         if (!opts_str)
1931                                 return -ENOMEM;
1932                         strcpy(opts_str, "context=");
1933                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1934                         strcat(opts_str, &data->context[0]);
1935                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1936                         kfree(opts_str);
1937                         if (rc)
1938                                 return rc;
1939 #else
1940                         return -EINVAL;
1941 #endif
1942                 }
1943
1944                 break;
1945         default:
1946                 return NFS_TEXT_DATA;
1947         }
1948
1949 #if !IS_ENABLED(CONFIG_NFS_V3)
1950         if (args->version == 3)
1951                 goto out_v3_not_compiled;
1952 #endif /* !CONFIG_NFS_V3 */
1953
1954         return 0;
1955
1956 out_no_data:
1957         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1958         return -EINVAL;
1959
1960 out_no_v3:
1961         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1962                  data->version);
1963         return -EINVAL;
1964
1965 out_no_sec:
1966         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1967         return -EINVAL;
1968
1969 #if !IS_ENABLED(CONFIG_NFS_V3)
1970 out_v3_not_compiled:
1971         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1972         return -EPROTONOSUPPORT;
1973 #endif /* !CONFIG_NFS_V3 */
1974
1975 out_nomem:
1976         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1977         return -ENOMEM;
1978
1979 out_no_address:
1980         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1981         return -EINVAL;
1982
1983 out_invalid_fh:
1984         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1985         return -EINVAL;
1986 }
1987
1988 #if IS_ENABLED(CONFIG_NFS_V4)
1989 static int nfs_validate_mount_data(struct file_system_type *fs_type,
1990                                    void *options,
1991                                    struct nfs_parsed_mount_data *args,
1992                                    struct nfs_fh *mntfh,
1993                                    const char *dev_name)
1994 {
1995         if (fs_type == &nfs_fs_type)
1996                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
1997         return nfs4_validate_mount_data(options, args, dev_name);
1998 }
1999 #else
2000 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2001                                    void *options,
2002                                    struct nfs_parsed_mount_data *args,
2003                                    struct nfs_fh *mntfh,
2004                                    const char *dev_name)
2005 {
2006         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2007 }
2008 #endif
2009
2010 static int nfs_validate_text_mount_data(void *options,
2011                                         struct nfs_parsed_mount_data *args,
2012                                         const char *dev_name)
2013 {
2014         int port = 0;
2015         int max_namelen = PAGE_SIZE;
2016         int max_pathlen = NFS_MAXPATHLEN;
2017         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2018
2019         if (nfs_parse_mount_options((char *)options, args) == 0)
2020                 return -EINVAL;
2021
2022         if (!nfs_verify_server_address(sap))
2023                 goto out_no_address;
2024
2025         if (args->version == 4) {
2026 #if IS_ENABLED(CONFIG_NFS_V4)
2027                 port = NFS_PORT;
2028                 max_namelen = NFS4_MAXNAMLEN;
2029                 max_pathlen = NFS4_MAXPATHLEN;
2030                 nfs_validate_transport_protocol(args);
2031                 nfs4_validate_mount_flags(args);
2032 #else
2033                 goto out_v4_not_compiled;
2034 #endif /* CONFIG_NFS_V4 */
2035         } else
2036                 nfs_set_mount_transport_protocol(args);
2037
2038         nfs_set_port(sap, &args->nfs_server.port, port);
2039
2040         if (args->auth_flavor_len > 1)
2041                 goto out_bad_auth;
2042
2043         return nfs_parse_devname(dev_name,
2044                                    &args->nfs_server.hostname,
2045                                    max_namelen,
2046                                    &args->nfs_server.export_path,
2047                                    max_pathlen);
2048
2049 #if !IS_ENABLED(CONFIG_NFS_V4)
2050 out_v4_not_compiled:
2051         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2052         return -EPROTONOSUPPORT;
2053 #endif /* !CONFIG_NFS_V4 */
2054
2055 out_no_address:
2056         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2057         return -EINVAL;
2058
2059 out_bad_auth:
2060         dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
2061         return -EINVAL;
2062 }
2063
2064 static int
2065 nfs_compare_remount_data(struct nfs_server *nfss,
2066                          struct nfs_parsed_mount_data *data)
2067 {
2068         if (data->flags != nfss->flags ||
2069             data->rsize != nfss->rsize ||
2070             data->wsize != nfss->wsize ||
2071             data->retrans != nfss->client->cl_timeout->to_retries ||
2072             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2073             data->acregmin != nfss->acregmin / HZ ||
2074             data->acregmax != nfss->acregmax / HZ ||
2075             data->acdirmin != nfss->acdirmin / HZ ||
2076             data->acdirmax != nfss->acdirmax / HZ ||
2077             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2078             data->nfs_server.port != nfss->port ||
2079             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2080             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2081                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2082                 return -EINVAL;
2083
2084         return 0;
2085 }
2086
2087 int
2088 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2089 {
2090         int error;
2091         struct nfs_server *nfss = sb->s_fs_info;
2092         struct nfs_parsed_mount_data *data;
2093         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2094         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2095         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2096
2097         /*
2098          * Userspace mount programs that send binary options generally send
2099          * them populated with default values. We have no way to know which
2100          * ones were explicitly specified. Fall back to legacy behavior and
2101          * just return success.
2102          */
2103         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2104             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2105                                            options->version <= 6))))
2106                 return 0;
2107
2108         data = kzalloc(sizeof(*data), GFP_KERNEL);
2109         if (data == NULL)
2110                 return -ENOMEM;
2111
2112         /* fill out struct with values from existing mount */
2113         data->flags = nfss->flags;
2114         data->rsize = nfss->rsize;
2115         data->wsize = nfss->wsize;
2116         data->retrans = nfss->client->cl_timeout->to_retries;
2117         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2118         data->acregmin = nfss->acregmin / HZ;
2119         data->acregmax = nfss->acregmax / HZ;
2120         data->acdirmin = nfss->acdirmin / HZ;
2121         data->acdirmax = nfss->acdirmax / HZ;
2122         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2123         data->nfs_server.port = nfss->port;
2124         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2125         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2126                 data->nfs_server.addrlen);
2127
2128         /* overwrite those values with any that were specified */
2129         error = nfs_parse_mount_options((char *)options, data);
2130         if (error < 0)
2131                 goto out;
2132
2133         /*
2134          * noac is a special case. It implies -o sync, but that's not
2135          * necessarily reflected in the mtab options. do_remount_sb
2136          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2137          * remount options, so we have to explicitly reset it.
2138          */
2139         if (data->flags & NFS_MOUNT_NOAC)
2140                 *flags |= MS_SYNCHRONOUS;
2141
2142         /* compare new mount options with old ones */
2143         error = nfs_compare_remount_data(nfss, data);
2144 out:
2145         kfree(data);
2146         return error;
2147 }
2148 EXPORT_SYMBOL_GPL(nfs_remount);
2149
2150 /*
2151  * Initialise the common bits of the superblock
2152  */
2153 inline void nfs_initialise_sb(struct super_block *sb)
2154 {
2155         struct nfs_server *server = NFS_SB(sb);
2156
2157         sb->s_magic = NFS_SUPER_MAGIC;
2158
2159         /* We probably want something more informative here */
2160         snprintf(sb->s_id, sizeof(sb->s_id),
2161                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2162
2163         if (sb->s_blocksize == 0)
2164                 sb->s_blocksize = nfs_block_bits(server->wsize,
2165                                                  &sb->s_blocksize_bits);
2166
2167         sb->s_bdi = &server->backing_dev_info;
2168
2169         nfs_super_set_maxbytes(sb, server->maxfilesize);
2170 }
2171
2172 /*
2173  * Finish setting up an NFS2/3 superblock
2174  */
2175 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2176 {
2177         struct nfs_parsed_mount_data *data = mount_info->parsed;
2178         struct nfs_server *server = NFS_SB(sb);
2179
2180         sb->s_blocksize_bits = 0;
2181         sb->s_blocksize = 0;
2182         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2183         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2184         if (data && data->bsize)
2185                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2186
2187         if (server->nfs_client->rpc_ops->version != 2) {
2188                 /* The VFS shouldn't apply the umask to mode bits. We will do
2189                  * so ourselves when necessary.
2190                  */
2191                 sb->s_flags |= MS_POSIXACL;
2192                 sb->s_time_gran = 1;
2193         }
2194
2195         nfs_initialise_sb(sb);
2196 }
2197 EXPORT_SYMBOL_GPL(nfs_fill_super);
2198
2199 /*
2200  * Finish setting up a cloned NFS2/3/4 superblock
2201  */
2202 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2203 {
2204         const struct super_block *old_sb = mount_info->cloned->sb;
2205         struct nfs_server *server = NFS_SB(sb);
2206
2207         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2208         sb->s_blocksize = old_sb->s_blocksize;
2209         sb->s_maxbytes = old_sb->s_maxbytes;
2210         sb->s_xattr = old_sb->s_xattr;
2211         sb->s_op = old_sb->s_op;
2212         sb->s_time_gran = 1;
2213
2214         if (server->nfs_client->rpc_ops->version != 2) {
2215                 /* The VFS shouldn't apply the umask to mode bits. We will do
2216                  * so ourselves when necessary.
2217                  */
2218                 sb->s_flags |= MS_POSIXACL;
2219         }
2220
2221         nfs_initialise_sb(sb);
2222 }
2223
2224 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2225 {
2226         const struct nfs_server *a = s->s_fs_info;
2227         const struct rpc_clnt *clnt_a = a->client;
2228         const struct rpc_clnt *clnt_b = b->client;
2229
2230         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2231                 goto Ebusy;
2232         if (a->nfs_client != b->nfs_client)
2233                 goto Ebusy;
2234         if (a->flags != b->flags)
2235                 goto Ebusy;
2236         if (a->wsize != b->wsize)
2237                 goto Ebusy;
2238         if (a->rsize != b->rsize)
2239                 goto Ebusy;
2240         if (a->acregmin != b->acregmin)
2241                 goto Ebusy;
2242         if (a->acregmax != b->acregmax)
2243                 goto Ebusy;
2244         if (a->acdirmin != b->acdirmin)
2245                 goto Ebusy;
2246         if (a->acdirmax != b->acdirmax)
2247                 goto Ebusy;
2248         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2249                 goto Ebusy;
2250         return 1;
2251 Ebusy:
2252         return 0;
2253 }
2254
2255 struct nfs_sb_mountdata {
2256         struct nfs_server *server;
2257         int mntflags;
2258 };
2259
2260 static int nfs_set_super(struct super_block *s, void *data)
2261 {
2262         struct nfs_sb_mountdata *sb_mntdata = data;
2263         struct nfs_server *server = sb_mntdata->server;
2264         int ret;
2265
2266         s->s_flags = sb_mntdata->mntflags;
2267         s->s_fs_info = server;
2268         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2269         ret = set_anon_super(s, server);
2270         if (ret == 0)
2271                 server->s_dev = s->s_dev;
2272         return ret;
2273 }
2274
2275 static int nfs_compare_super_address(struct nfs_server *server1,
2276                                      struct nfs_server *server2)
2277 {
2278         struct sockaddr *sap1, *sap2;
2279
2280         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2281         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2282
2283         if (sap1->sa_family != sap2->sa_family)
2284                 return 0;
2285
2286         switch (sap1->sa_family) {
2287         case AF_INET: {
2288                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2289                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2290                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2291                         return 0;
2292                 if (sin1->sin_port != sin2->sin_port)
2293                         return 0;
2294                 break;
2295         }
2296         case AF_INET6: {
2297                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2298                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2299                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2300                         return 0;
2301                 if (sin1->sin6_port != sin2->sin6_port)
2302                         return 0;
2303                 break;
2304         }
2305         default:
2306                 return 0;
2307         }
2308
2309         return 1;
2310 }
2311
2312 static int nfs_compare_super(struct super_block *sb, void *data)
2313 {
2314         struct nfs_sb_mountdata *sb_mntdata = data;
2315         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2316         int mntflags = sb_mntdata->mntflags;
2317
2318         if (!nfs_compare_super_address(old, server))
2319                 return 0;
2320         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2321         if (old->flags & NFS_MOUNT_UNSHARED)
2322                 return 0;
2323         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2324                 return 0;
2325         return nfs_compare_mount_options(sb, server, mntflags);
2326 }
2327
2328 #ifdef CONFIG_NFS_FSCACHE
2329 static void nfs_get_cache_cookie(struct super_block *sb,
2330                                  struct nfs_parsed_mount_data *parsed,
2331                                  struct nfs_clone_mount *cloned)
2332 {
2333         struct nfs_server *nfss = NFS_SB(sb);
2334         char *uniq = NULL;
2335         int ulen = 0;
2336
2337         nfss->fscache_key = NULL;
2338         nfss->fscache = NULL;
2339
2340         if (parsed) {
2341                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2342                         return;
2343                 if (parsed->fscache_uniq) {
2344                         uniq = parsed->fscache_uniq;
2345                         ulen = strlen(parsed->fscache_uniq);
2346                 }
2347         } else if (cloned) {
2348                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2349                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2350                         return;
2351                 if (mnt_s->fscache_key) {
2352                         uniq = mnt_s->fscache_key->key.uniquifier;
2353                         ulen = mnt_s->fscache_key->key.uniq_len;
2354                 };
2355         } else
2356                 return;
2357
2358         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2359 }
2360 #else
2361 static void nfs_get_cache_cookie(struct super_block *sb,
2362                                  struct nfs_parsed_mount_data *parsed,
2363                                  struct nfs_clone_mount *cloned)
2364 {
2365 }
2366 #endif
2367
2368 static int nfs_bdi_register(struct nfs_server *server)
2369 {
2370         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2371 }
2372
2373 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2374                         struct nfs_mount_info *mount_info)
2375 {
2376         return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts);
2377 }
2378 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2379
2380 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2381                           struct nfs_mount_info *mount_info)
2382 {
2383         /* clone any lsm security options from the parent to the new sb */
2384         security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2385         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2386                 return -ESTALE;
2387         return 0;
2388 }
2389 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2390
2391 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2392                                    int flags, const char *dev_name,
2393                                    struct nfs_mount_info *mount_info,
2394                                    struct nfs_subversion *nfs_mod)
2395 {
2396         struct super_block *s;
2397         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2398         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2399         struct nfs_sb_mountdata sb_mntdata = {
2400                 .mntflags = flags,
2401                 .server = server,
2402         };
2403         int error;
2404
2405         if (server->flags & NFS_MOUNT_UNSHARED)
2406                 compare_super = NULL;
2407
2408         /* -o noac implies -o sync */
2409         if (server->flags & NFS_MOUNT_NOAC)
2410                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2411
2412         /* Get a superblock - note that we may end up sharing one that already exists */
2413         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2414         if (IS_ERR(s)) {
2415                 mntroot = ERR_CAST(s);
2416                 goto out_err_nosb;
2417         }
2418
2419         if (s->s_fs_info != server) {
2420                 nfs_free_server(server);
2421                 server = NULL;
2422         } else {
2423                 error = nfs_bdi_register(server);
2424                 if (error) {
2425                         mntroot = ERR_PTR(error);
2426                         goto error_splat_bdi;
2427                 }
2428         }
2429
2430         if (!s->s_root) {
2431                 /* initial superblock/root creation */
2432                 mount_info->fill_super(s, mount_info);
2433                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2434         }
2435
2436         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2437         if (IS_ERR(mntroot))
2438                 goto error_splat_super;
2439
2440         error = mount_info->set_security(s, mntroot, mount_info);
2441         if (error)
2442                 goto error_splat_root;
2443
2444         s->s_flags |= MS_ACTIVE;
2445
2446 out:
2447         return mntroot;
2448
2449 out_err_nosb:
2450         nfs_free_server(server);
2451         goto out;
2452
2453 error_splat_root:
2454         dput(mntroot);
2455         mntroot = ERR_PTR(error);
2456 error_splat_super:
2457         if (server && !s->s_root)
2458                 bdi_unregister(&server->backing_dev_info);
2459 error_splat_bdi:
2460         deactivate_locked_super(s);
2461         goto out;
2462 }
2463 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2464
2465 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2466         int flags, const char *dev_name, void *raw_data)
2467 {
2468         struct nfs_mount_info mount_info = {
2469                 .fill_super = nfs_fill_super,
2470                 .set_security = nfs_set_sb_security,
2471         };
2472         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2473         struct nfs_subversion *nfs_mod;
2474         int error;
2475
2476         mount_info.parsed = nfs_alloc_parsed_mount_data();
2477         mount_info.mntfh = nfs_alloc_fhandle();
2478         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2479                 goto out;
2480
2481         /* Validate the mount data */
2482         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2483         if (error == NFS_TEXT_DATA)
2484                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2485         if (error < 0) {
2486                 mntroot = ERR_PTR(error);
2487                 goto out;
2488         }
2489
2490         nfs_mod = get_nfs_version(mount_info.parsed->version);
2491         if (IS_ERR(nfs_mod)) {
2492                 mntroot = ERR_CAST(nfs_mod);
2493                 goto out;
2494         }
2495
2496         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2497
2498         put_nfs_version(nfs_mod);
2499 out:
2500         nfs_free_parsed_mount_data(mount_info.parsed);
2501         nfs_free_fhandle(mount_info.mntfh);
2502         return mntroot;
2503 }
2504 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2505
2506 /*
2507  * Ensure that we unregister the bdi before kill_anon_super
2508  * releases the device name
2509  */
2510 void nfs_put_super(struct super_block *s)
2511 {
2512         struct nfs_server *server = NFS_SB(s);
2513
2514         bdi_unregister(&server->backing_dev_info);
2515 }
2516 EXPORT_SYMBOL_GPL(nfs_put_super);
2517
2518 /*
2519  * Destroy an NFS2/3 superblock
2520  */
2521 void nfs_kill_super(struct super_block *s)
2522 {
2523         struct nfs_server *server = NFS_SB(s);
2524
2525         kill_anon_super(s);
2526         nfs_fscache_release_super_cookie(s);
2527         nfs_free_server(server);
2528 }
2529 EXPORT_SYMBOL_GPL(nfs_kill_super);
2530
2531 /*
2532  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2533  */
2534 static struct dentry *
2535 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2536                 const char *dev_name, void *raw_data)
2537 {
2538         struct nfs_clone_mount *data = raw_data;
2539         struct nfs_mount_info mount_info = {
2540                 .fill_super = nfs_clone_super,
2541                 .set_security = nfs_clone_sb_security,
2542                 .cloned = data,
2543         };
2544         struct nfs_server *server;
2545         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2546         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2547
2548         dprintk("--> nfs_xdev_mount()\n");
2549
2550         mount_info.mntfh = mount_info.cloned->fh;
2551
2552         /* create a new volume representation */
2553         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2554
2555         if (IS_ERR(server))
2556                 mntroot = ERR_CAST(server);
2557         else
2558                 mntroot = nfs_fs_mount_common(server, flags,
2559                                 dev_name, &mount_info, nfs_mod);
2560
2561         dprintk("<-- nfs_xdev_mount() = %ld\n",
2562                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2563         return mntroot;
2564 }
2565
2566 #if IS_ENABLED(CONFIG_NFS_V4)
2567
2568 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2569 {
2570         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2571                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2572 }
2573
2574 /*
2575  * Validate NFSv4 mount options
2576  */
2577 static int nfs4_validate_mount_data(void *options,
2578                                     struct nfs_parsed_mount_data *args,
2579                                     const char *dev_name)
2580 {
2581         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2582         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2583         char *c;
2584
2585         if (data == NULL)
2586                 goto out_no_data;
2587
2588         args->version = 4;
2589
2590         switch (data->version) {
2591         case 1:
2592                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2593                         goto out_no_address;
2594                 if (data->host_addrlen == 0)
2595                         goto out_no_address;
2596                 args->nfs_server.addrlen = data->host_addrlen;
2597                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2598                         return -EFAULT;
2599                 if (!nfs_verify_server_address(sap))
2600                         goto out_no_address;
2601                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2602
2603                 if (data->auth_flavourlen) {
2604                         if (data->auth_flavourlen > 1)
2605                                 goto out_inval_auth;
2606                         if (copy_from_user(&args->auth_flavors[0],
2607                                            data->auth_flavours,
2608                                            sizeof(args->auth_flavors[0])))
2609                                 return -EFAULT;
2610                 }
2611
2612                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2613                 if (IS_ERR(c))
2614                         return PTR_ERR(c);
2615                 args->nfs_server.hostname = c;
2616
2617                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2618                 if (IS_ERR(c))
2619                         return PTR_ERR(c);
2620                 args->nfs_server.export_path = c;
2621                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2622
2623                 c = strndup_user(data->client_addr.data, 16);
2624                 if (IS_ERR(c))
2625                         return PTR_ERR(c);
2626                 args->client_address = c;
2627
2628                 /*
2629                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2630                  * can deal with.
2631                  */
2632
2633                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2634                 args->rsize     = data->rsize;
2635                 args->wsize     = data->wsize;
2636                 args->timeo     = data->timeo;
2637                 args->retrans   = data->retrans;
2638                 args->acregmin  = data->acregmin;
2639                 args->acregmax  = data->acregmax;
2640                 args->acdirmin  = data->acdirmin;
2641                 args->acdirmax  = data->acdirmax;
2642                 args->nfs_server.protocol = data->proto;
2643                 nfs_validate_transport_protocol(args);
2644
2645                 break;
2646         default:
2647                 return NFS_TEXT_DATA;
2648         }
2649
2650         return 0;
2651
2652 out_no_data:
2653         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2654         return -EINVAL;
2655
2656 out_inval_auth:
2657         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2658                  data->auth_flavourlen);
2659         return -EINVAL;
2660
2661 out_no_address:
2662         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2663         return -EINVAL;
2664 }
2665
2666 /*
2667  * NFS v4 module parameters need to stay in the
2668  * NFS client for backwards compatibility
2669  */
2670 unsigned int nfs_callback_set_tcpport;
2671 unsigned short nfs_callback_tcpport;
2672 /* Default cache timeout is 10 minutes */
2673 unsigned int nfs_idmap_cache_timeout = 600;
2674 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2675 bool nfs4_disable_idmapping = true;
2676 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2677 unsigned short send_implementation_id = 1;
2678 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2679
2680 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2681 EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2682 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2683 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2684 EXPORT_SYMBOL_GPL(max_session_slots);
2685 EXPORT_SYMBOL_GPL(send_implementation_id);
2686 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2687
2688 #define NFS_CALLBACK_MAXPORTNR (65535U)
2689
2690 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2691 {
2692         unsigned long num;
2693         int ret;
2694
2695         if (!val)
2696                 return -EINVAL;
2697         ret = kstrtoul(val, 0, &num);
2698         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2699                 return -EINVAL;
2700         *((unsigned int *)kp->arg) = num;
2701         return 0;
2702 }
2703 static struct kernel_param_ops param_ops_portnr = {
2704         .set = param_set_portnr,
2705         .get = param_get_uint,
2706 };
2707 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2708
2709 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2710 module_param(nfs_idmap_cache_timeout, int, 0644);
2711 module_param(nfs4_disable_idmapping, bool, 0644);
2712 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2713                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2714 MODULE_PARM_DESC(nfs4_disable_idmapping,
2715                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2716 module_param(max_session_slots, ushort, 0644);
2717 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2718                 "requests the client will negotiate");
2719 module_param(send_implementation_id, ushort, 0644);
2720 MODULE_PARM_DESC(send_implementation_id,
2721                 "Send implementation ID with NFSv4.1 exchange_id");
2722 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2723
2724 #endif /* CONFIG_NFS_V4 */