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, Opt_vers_4_2,
 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         { Opt_vers_4_2, "4.2" },
 284
 285         { Opt_vers_err, NULL }
 286 };
 287
 288 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 289                 int flags, const char *dev_name, void *raw_data);
 290
 291 struct file_system_type nfs_fs_type = {
 292         .owner          = THIS_MODULE,
 293         .name           = "nfs",
 294         .mount          = nfs_fs_mount,
 295         .kill_sb        = nfs_kill_super,
 296         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 297 };
 298 MODULE_ALIAS_FS("nfs");
 299 EXPORT_SYMBOL_GPL(nfs_fs_type);
 300
 301 struct file_system_type nfs_xdev_fs_type = {
 302         .owner          = THIS_MODULE,
 303         .name           = "nfs",
 304         .mount          = nfs_xdev_mount,
 305         .kill_sb        = nfs_kill_super,
 306         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 307 };
 308
 309 const struct super_operations nfs_sops = {
 310         .alloc_inode    = nfs_alloc_inode,
 311         .destroy_inode  = nfs_destroy_inode,
 312         .write_inode    = nfs_write_inode,
 313         .drop_inode     = nfs_drop_inode,
 314         .put_super      = nfs_put_super,
 315         .statfs         = nfs_statfs,
 316         .evict_inode    = nfs_evict_inode,
 317         .umount_begin   = nfs_umount_begin,
 318         .show_options   = nfs_show_options,
 319         .show_devname   = nfs_show_devname,
 320         .show_path      = nfs_show_path,
 321         .show_stats     = nfs_show_stats,
 322         .remount_fs     = nfs_remount,
 323 };
 324 EXPORT_SYMBOL_GPL(nfs_sops);
 325
 326 #if IS_ENABLED(CONFIG_NFS_V4)
 327 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 328 static int nfs4_validate_mount_data(void *options,
 329         struct nfs_parsed_mount_data *args, const char *dev_name);
 330
 331 struct file_system_type nfs4_fs_type = {
 332         .owner          = THIS_MODULE,
 333         .name           = "nfs4",
 334         .mount          = nfs_fs_mount,
 335         .kill_sb        = nfs_kill_super,
 336         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 337 };
 338 MODULE_ALIAS_FS("nfs4");
 339 MODULE_ALIAS("nfs4");
 340 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 341
 342 static int __init register_nfs4_fs(void)
 343 {
 344         return register_filesystem(&nfs4_fs_type);
 345 }
 346
 347 static void unregister_nfs4_fs(void)
 348 {
 349         unregister_filesystem(&nfs4_fs_type);
 350 }
 351 #else
 352 static int __init register_nfs4_fs(void)
 353 {
 354         return 0;
 355 }
 356
 357 static void unregister_nfs4_fs(void)
 358 {
 359 }
 360 #endif
 361
 362 static struct shrinker acl_shrinker = {
 363         .count_objects  = nfs_access_cache_count,
 364         .scan_objects   = nfs_access_cache_scan,
 365         .seeks          = DEFAULT_SEEKS,
 366 };
 367
 368 /*
 369  * Register the NFS filesystems
 370  */
 371 int __init register_nfs_fs(void)
 372 {
 373         int ret;
 374
 375         ret = register_filesystem(&nfs_fs_type);
 376         if (ret < 0)
 377                 goto error_0;
 378
 379         ret = register_nfs4_fs();
 380         if (ret < 0)
 381                 goto error_1;
 382
 383         ret = nfs_register_sysctl();
 384         if (ret < 0)
 385                 goto error_2;
 386         register_shrinker(&acl_shrinker);
 387         return 0;
 388
 389 error_2:
 390         unregister_nfs4_fs();
 391 error_1:
 392         unregister_filesystem(&nfs_fs_type);
 393 error_0:
 394         return ret;
 395 }
 396
 397 /*
 398  * Unregister the NFS filesystems
 399  */
 400 void __exit unregister_nfs_fs(void)
 401 {
 402         unregister_shrinker(&acl_shrinker);
 403         nfs_unregister_sysctl();
 404         unregister_nfs4_fs();
 405         unregister_filesystem(&nfs_fs_type);
 406 }
 407
 408 void nfs_sb_active(struct super_block *sb)
 409 {
 410         struct nfs_server *server = NFS_SB(sb);
 411
 412         if (atomic_inc_return(&server->active) == 1)
 413                 atomic_inc(&sb->s_active);
 414 }
 415 EXPORT_SYMBOL_GPL(nfs_sb_active);
 416
 417 void nfs_sb_deactive(struct super_block *sb)
 418 {
 419         struct nfs_server *server = NFS_SB(sb);
 420
 421         if (atomic_dec_and_test(&server->active))
 422                 deactivate_super(sb);
 423 }
 424 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 425
 426 /*
 427  * Deliver file system statistics to userspace
 428  */
 429 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 430 {
 431         struct nfs_server *server = NFS_SB(dentry->d_sb);
 432         unsigned char blockbits;
 433         unsigned long blockres;
 434         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 435         struct nfs_fsstat res;
 436         int error = -ENOMEM;
 437
 438         res.fattr = nfs_alloc_fattr();
 439         if (res.fattr == NULL)
 440                 goto out_err;
 441
 442         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 443         if (unlikely(error == -ESTALE)) {
 444                 struct dentry *pd_dentry;
 445
 446                 pd_dentry = dget_parent(dentry);
 447                 if (pd_dentry != NULL) {
 448                         nfs_zap_caches(pd_dentry->d_inode);
 449                         dput(pd_dentry);
 450                 }
 451         }
 452         nfs_free_fattr(res.fattr);
 453         if (error < 0)
 454                 goto out_err;
 455
 456         buf->f_type = NFS_SUPER_MAGIC;
 457
 458         /*
 459          * Current versions of glibc do not correctly handle the
 460          * case where f_frsize != f_bsize.  Eventually we want to
 461          * report the value of wtmult in this field.
 462          */
 463         buf->f_frsize = dentry->d_sb->s_blocksize;
 464
 465         /*
 466          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 467          * are reported in units of f_frsize.  Linux hasn't had
 468          * an f_frsize field in its statfs struct until recently,
 469          * thus historically Linux's sys_statfs reports these
 470          * fields in units of f_bsize.
 471          */
 472         buf->f_bsize = dentry->d_sb->s_blocksize;
 473         blockbits = dentry->d_sb->s_blocksize_bits;
 474         blockres = (1 << blockbits) - 1;
 475         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 476         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 477         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 478
 479         buf->f_files = res.tfiles;
 480         buf->f_ffree = res.afiles;
 481
 482         buf->f_namelen = server->namelen;
 483
 484         return 0;
 485
 486  out_err:
 487         dprintk("%s: statfs error = %d\n", __func__, -error);
 488         return error;
 489 }
 490 EXPORT_SYMBOL_GPL(nfs_statfs);
 491
 492 /*
 493  * Map the security flavour number to a name
 494  */
 495 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 496 {
 497         static const struct {
 498                 rpc_authflavor_t flavour;
 499                 const char *str;
 500         } sec_flavours[] = {
 501                 { RPC_AUTH_NULL, "null" },
 502                 { RPC_AUTH_UNIX, "sys" },
 503                 { RPC_AUTH_GSS_KRB5, "krb5" },
 504                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 505                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 506                 { RPC_AUTH_GSS_LKEY, "lkey" },
 507                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 508                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 509                 { RPC_AUTH_GSS_SPKM, "spkm" },
 510                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 511                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 512                 { UINT_MAX, "unknown" }
 513         };
 514         int i;
 515
 516         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 517                 if (sec_flavours[i].flavour == flavour)
 518                         break;
 519         }
 520         return sec_flavours[i].str;
 521 }
 522
 523 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 524                                   int showdefaults)
 525 {
 526         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 527
 528         seq_printf(m, ",mountproto=");
 529         switch (sap->sa_family) {
 530         case AF_INET:
 531                 switch (nfss->mountd_protocol) {
 532                 case IPPROTO_UDP:
 533                         seq_printf(m, RPCBIND_NETID_UDP);
 534                         break;
 535                 case IPPROTO_TCP:
 536                         seq_printf(m, RPCBIND_NETID_TCP);
 537                         break;
 538                 default:
 539                         if (showdefaults)
 540                                 seq_printf(m, "auto");
 541                 }
 542                 break;
 543         case AF_INET6:
 544                 switch (nfss->mountd_protocol) {
 545                 case IPPROTO_UDP:
 546                         seq_printf(m, RPCBIND_NETID_UDP6);
 547                         break;
 548                 case IPPROTO_TCP:
 549                         seq_printf(m, RPCBIND_NETID_TCP6);
 550                         break;
 551                 default:
 552                         if (showdefaults)
 553                                 seq_printf(m, "auto");
 554                 }
 555                 break;
 556         default:
 557                 if (showdefaults)
 558                         seq_printf(m, "auto");
 559         }
 560 }
 561
 562 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 563                                     int showdefaults)
 564 {
 565         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 566
 567         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 568                 return;
 569
 570         switch (sap->sa_family) {
 571         case AF_INET: {
 572                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 573                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 574                 break;
 575         }
 576         case AF_INET6: {
 577                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 578                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 579                 break;
 580         }
 581         default:
 582                 if (showdefaults)
 583                         seq_printf(m, ",mountaddr=unspecified");
 584         }
 585
 586         if (nfss->mountd_version || showdefaults)
 587                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 588         if ((nfss->mountd_port &&
 589                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 590                 showdefaults)
 591                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 592
 593         nfs_show_mountd_netid(m, nfss, showdefaults);
 594 }
 595
 596 #if IS_ENABLED(CONFIG_NFS_V4)
 597 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 598                                     int showdefaults)
 599 {
 600         struct nfs_client *clp = nfss->nfs_client;
 601
 602         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 603 }
 604 #else
 605 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 606                                     int showdefaults)
 607 {
 608 }
 609 #endif
 610
 611 static void nfs_show_nfs_version(struct seq_file *m,
 612                 unsigned int version,
 613                 unsigned int minorversion)
 614 {
 615         seq_printf(m, ",vers=%u", version);
 616         if (version == 4)
 617                 seq_printf(m, ".%u", minorversion);
 618 }
 619
 620 /*
 621  * Describe the mount options in force on this server representation
 622  */
 623 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 624                                    int showdefaults)
 625 {
 626         static const struct proc_nfs_info {
 627                 int flag;
 628                 const char *str;
 629                 const char *nostr;
 630         } nfs_info[] = {
 631                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 632                 { NFS_MOUNT_POSIX, ",posix", "" },
 633                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 634                 { NFS_MOUNT_NOAC, ",noac", "" },
 635                 { NFS_MOUNT_NONLM, ",nolock", "" },
 636                 { NFS_MOUNT_NOACL, ",noacl", "" },
 637                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 638                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 639                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 640                 { 0, NULL, NULL }
 641         };
 642         const struct proc_nfs_info *nfs_infop;
 643         struct nfs_client *clp = nfss->nfs_client;
 644         u32 version = clp->rpc_ops->version;
 645         int local_flock, local_fcntl;
 646
 647         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 648         seq_printf(m, ",rsize=%u", nfss->rsize);
 649         seq_printf(m, ",wsize=%u", nfss->wsize);
 650         if (nfss->bsize != 0)
 651                 seq_printf(m, ",bsize=%u", nfss->bsize);
 652         seq_printf(m, ",namlen=%u", nfss->namelen);
 653         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 654                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 655         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 656                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 657         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 658                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 659         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 660                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 661         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 662                 if (nfss->flags & nfs_infop->flag)
 663                         seq_puts(m, nfs_infop->str);
 664                 else
 665                         seq_puts(m, nfs_infop->nostr);
 666         }
 667         rcu_read_lock();
 668         seq_printf(m, ",proto=%s",
 669                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 670         rcu_read_unlock();
 671         if (version == 4) {
 672                 if (nfss->port != NFS_PORT)
 673                         seq_printf(m, ",port=%u", nfss->port);
 674         } else
 675                 if (nfss->port)
 676                         seq_printf(m, ",port=%u", nfss->port);
 677
 678         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 679         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 680         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 681
 682         if (version != 4)
 683                 nfs_show_mountd_options(m, nfss, showdefaults);
 684         else
 685                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 686
 687         if (nfss->options & NFS_OPTION_FSCACHE)
 688                 seq_printf(m, ",fsc");
 689
 690         if (nfss->options & NFS_OPTION_MIGRATION)
 691                 seq_printf(m, ",migration");
 692
 693         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 694                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 695                         seq_printf(m, ",lookupcache=none");
 696                 else
 697                         seq_printf(m, ",lookupcache=pos");
 698         }
 699
 700         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 701         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 702
 703         if (!local_flock && !local_fcntl)
 704                 seq_printf(m, ",local_lock=none");
 705         else if (local_flock && local_fcntl)
 706                 seq_printf(m, ",local_lock=all");
 707         else if (local_flock)
 708                 seq_printf(m, ",local_lock=flock");
 709         else
 710                 seq_printf(m, ",local_lock=posix");
 711 }
 712
 713 /*
 714  * Describe the mount options on this VFS mountpoint
 715  */
 716 int nfs_show_options(struct seq_file *m, struct dentry *root)
 717 {
 718         struct nfs_server *nfss = NFS_SB(root->d_sb);
 719
 720         nfs_show_mount_options(m, nfss, 0);
 721
 722         rcu_read_lock();
 723         seq_printf(m, ",addr=%s",
 724                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 725                                                         RPC_DISPLAY_ADDR));
 726         rcu_read_unlock();
 727
 728         return 0;
 729 }
 730 EXPORT_SYMBOL_GPL(nfs_show_options);
 731
 732 #if IS_ENABLED(CONFIG_NFS_V4)
 733 #ifdef CONFIG_NFS_V4_1
 734 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 735 {
 736         if (nfs4_has_session(server->nfs_client))
 737                 seq_printf(m, ",sessions");
 738 }
 739 #else
 740 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 741 #endif
 742 #endif
 743
 744 #ifdef CONFIG_NFS_V4_1
 745 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 746 {
 747         seq_printf(m, ",pnfs=");
 748         if (server->pnfs_curr_ld)
 749                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 750         else
 751                 seq_printf(m, "not configured");
 752 }
 753
 754 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 755 {
 756         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 757                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 758                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 759                            "date='%llu,%u'",
 760                            impl_id->name, impl_id->domain,
 761                            impl_id->date.seconds, impl_id->date.nseconds);
 762         }
 763 }
 764 #else
 765 #if IS_ENABLED(CONFIG_NFS_V4)
 766 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 767 {
 768 }
 769 #endif
 770 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 771 {
 772 }
 773 #endif
 774
 775 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 776 {
 777         char *page = (char *) __get_free_page(GFP_KERNEL);
 778         char *devname, *dummy;
 779         int err = 0;
 780         if (!page)
 781                 return -ENOMEM;
 782         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 783         if (IS_ERR(devname))
 784                 err = PTR_ERR(devname);
 785         else
 786                 seq_escape(m, devname, " \t\n\\");
 787         free_page((unsigned long)page);
 788         return err;
 789 }
 790 EXPORT_SYMBOL_GPL(nfs_show_devname);
 791
 792 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 793 {
 794         seq_puts(m, "/");
 795         return 0;
 796 }
 797 EXPORT_SYMBOL_GPL(nfs_show_path);
 798
 799 /*
 800  * Present statistical information for this VFS mountpoint
 801  */
 802 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 803 {
 804         int i, cpu;
 805         struct nfs_server *nfss = NFS_SB(root->d_sb);
 806         struct rpc_auth *auth = nfss->client->cl_auth;
 807         struct nfs_iostats totals = { };
 808
 809         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 810
 811         /*
 812          * Display all mount option settings
 813          */
 814         seq_printf(m, "\n\topts:\t");
 815         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 816         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 817         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 818         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 819         nfs_show_mount_options(m, nfss, 1);
 820
 821         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 822
 823         show_implementation_id(m, nfss);
 824
 825         seq_printf(m, "\n\tcaps:\t");
 826         seq_printf(m, "caps=0x%x", nfss->caps);
 827         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 828         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 829         seq_printf(m, ",bsize=%u", nfss->bsize);
 830         seq_printf(m, ",namlen=%u", nfss->namelen);
 831
 832 #if IS_ENABLED(CONFIG_NFS_V4)
 833         if (nfss->nfs_client->rpc_ops->version == 4) {
 834                 seq_printf(m, "\n\tnfsv4:\t");
 835                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 836                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 837                 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
 838                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 839                 show_sessions(m, nfss);
 840                 show_pnfs(m, nfss);
 841         }
 842 #endif
 843
 844         /*
 845          * Display security flavor in effect for this mount
 846          */
 847         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 848         if (auth->au_flavor)
 849                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 850
 851         /*
 852          * Display superblock I/O counters
 853          */
 854         for_each_possible_cpu(cpu) {
 855                 struct nfs_iostats *stats;
 856
 857                 preempt_disable();
 858                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 859
 860                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 861                         totals.events[i] += stats->events[i];
 862                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 863                         totals.bytes[i] += stats->bytes[i];
 864 #ifdef CONFIG_NFS_FSCACHE
 865                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 866                         totals.fscache[i] += stats->fscache[i];
 867 #endif
 868
 869                 preempt_enable();
 870         }
 871
 872         seq_printf(m, "\n\tevents:\t");
 873         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 874                 seq_printf(m, "%lu ", totals.events[i]);
 875         seq_printf(m, "\n\tbytes:\t");
 876         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 877                 seq_printf(m, "%Lu ", totals.bytes[i]);
 878 #ifdef CONFIG_NFS_FSCACHE
 879         if (nfss->options & NFS_OPTION_FSCACHE) {
 880                 seq_printf(m, "\n\tfsc:\t");
 881                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 882                         seq_printf(m, "%Lu ", totals.bytes[i]);
 883         }
 884 #endif
 885         seq_printf(m, "\n");
 886
 887         rpc_print_iostats(m, nfss->client);
 888
 889         return 0;
 890 }
 891 EXPORT_SYMBOL_GPL(nfs_show_stats);
 892
 893 /*
 894  * Begin unmount by attempting to remove all automounted mountpoints we added
 895  * in response to xdev traversals and referrals
 896  */
 897 void nfs_umount_begin(struct super_block *sb)
 898 {
 899         struct nfs_server *server;
 900         struct rpc_clnt *rpc;
 901
 902         server = NFS_SB(sb);
 903         /* -EIO all pending I/O */
 904         rpc = server->client_acl;
 905         if (!IS_ERR(rpc))
 906                 rpc_killall_tasks(rpc);
 907         rpc = server->client;
 908         if (!IS_ERR(rpc))
 909                 rpc_killall_tasks(rpc);
 910 }
 911 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 912
 913 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 914 {
 915         struct nfs_parsed_mount_data *data;
 916
 917         data = kzalloc(sizeof(*data), GFP_KERNEL);
 918         if (data) {
 919                 data->acregmin          = NFS_DEF_ACREGMIN;
 920                 data->acregmax          = NFS_DEF_ACREGMAX;
 921                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 922                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 923                 data->mount_server.port = NFS_UNSPEC_PORT;
 924                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 925                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 926                 data->selected_flavor   = RPC_AUTH_MAXFLAVOR;
 927                 data->minorversion      = 0;
 928                 data->need_mount        = true;
 929                 data->net               = current->nsproxy->net_ns;
 930                 security_init_mnt_opts(&data->lsm_opts);
 931         }
 932         return data;
 933 }
 934
 935 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 936 {
 937         if (data) {
 938                 kfree(data->client_address);
 939                 kfree(data->mount_server.hostname);
 940                 kfree(data->nfs_server.export_path);
 941                 kfree(data->nfs_server.hostname);
 942                 kfree(data->fscache_uniq);
 943                 security_free_mnt_opts(&data->lsm_opts);
 944                 kfree(data);
 945         }
 946 }
 947
 948 /*
 949  * Sanity-check a server address provided by the mount command.
 950  *
 951  * Address family must be initialized, and address must not be
 952  * the ANY address for that family.
 953  */
 954 static int nfs_verify_server_address(struct sockaddr *addr)
 955 {
 956         switch (addr->sa_family) {
 957         case AF_INET: {
 958                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 959                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 960         }
 961         case AF_INET6: {
 962                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 963                 return !ipv6_addr_any(sa);
 964         }
 965         }
 966
 967         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 968         return 0;
 969 }
 970
 971 /*
 972  * Select between a default port value and a user-specified port value.
 973  * If a zero value is set, then autobind will be used.
 974  */
 975 static void nfs_set_port(struct sockaddr *sap, int *port,
 976                                  const unsigned short default_port)
 977 {
 978         if (*port == NFS_UNSPEC_PORT)
 979                 *port = default_port;
 980
 981         rpc_set_port(sap, *port);
 982 }
 983
 984 /*
 985  * Sanity check the NFS transport protocol.
 986  *
 987  */
 988 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 989 {
 990         switch (mnt->nfs_server.protocol) {
 991         case XPRT_TRANSPORT_UDP:
 992         case XPRT_TRANSPORT_TCP:
 993         case XPRT_TRANSPORT_RDMA:
 994                 break;
 995         default:
 996                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 997         }
 998 }
 999
1000 /*
1001  * For text based NFSv2/v3 mounts, the mount protocol transport default
1002  * settings should depend upon the specified NFS transport.
1003  */
1004 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1005 {
1006         nfs_validate_transport_protocol(mnt);
1007
1008         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1009             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1010                         return;
1011         switch (mnt->nfs_server.protocol) {
1012         case XPRT_TRANSPORT_UDP:
1013                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1014                 break;
1015         case XPRT_TRANSPORT_TCP:
1016         case XPRT_TRANSPORT_RDMA:
1017                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1018         }
1019 }
1020
1021 /*
1022  * Parse the value of the 'sec=' option.
1023  */
1024 static int nfs_parse_security_flavors(char *value,
1025                                       struct nfs_parsed_mount_data *mnt)
1026 {
1027         substring_t args[MAX_OPT_ARGS];
1028         rpc_authflavor_t pseudoflavor;
1029
1030         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1031
1032         switch (match_token(value, nfs_secflavor_tokens, args)) {
1033         case Opt_sec_none:
1034                 pseudoflavor = RPC_AUTH_NULL;
1035                 break;
1036         case Opt_sec_sys:
1037                 pseudoflavor = RPC_AUTH_UNIX;
1038                 break;
1039         case Opt_sec_krb5:
1040                 pseudoflavor = RPC_AUTH_GSS_KRB5;
1041                 break;
1042         case Opt_sec_krb5i:
1043                 pseudoflavor = RPC_AUTH_GSS_KRB5I;
1044                 break;
1045         case Opt_sec_krb5p:
1046                 pseudoflavor = RPC_AUTH_GSS_KRB5P;
1047                 break;
1048         case Opt_sec_lkey:
1049                 pseudoflavor = RPC_AUTH_GSS_LKEY;
1050                 break;
1051         case Opt_sec_lkeyi:
1052                 pseudoflavor = RPC_AUTH_GSS_LKEYI;
1053                 break;
1054         case Opt_sec_lkeyp:
1055                 pseudoflavor = RPC_AUTH_GSS_LKEYP;
1056                 break;
1057         case Opt_sec_spkm:
1058                 pseudoflavor = RPC_AUTH_GSS_SPKM;
1059                 break;
1060         case Opt_sec_spkmi:
1061                 pseudoflavor = RPC_AUTH_GSS_SPKMI;
1062                 break;
1063         case Opt_sec_spkmp:
1064                 pseudoflavor = RPC_AUTH_GSS_SPKMP;
1065                 break;
1066         default:
1067                 return 0;
1068         }
1069
1070         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1071         mnt->auth_info.flavors[0] = pseudoflavor;
1072         mnt->auth_info.flavor_len = 1;
1073         return 1;
1074 }
1075
1076 static int nfs_parse_version_string(char *string,
1077                 struct nfs_parsed_mount_data *mnt,
1078                 substring_t *args)
1079 {
1080         mnt->flags &= ~NFS_MOUNT_VER3;
1081         switch (match_token(string, nfs_vers_tokens, args)) {
1082         case Opt_vers_2:
1083                 mnt->version = 2;
1084                 break;
1085         case Opt_vers_3:
1086                 mnt->flags |= NFS_MOUNT_VER3;
1087                 mnt->version = 3;
1088                 break;
1089         case Opt_vers_4:
1090                 /* Backward compatibility option. In future,
1091                  * the mount program should always supply
1092                  * a NFSv4 minor version number.
1093                  */
1094                 mnt->version = 4;
1095                 break;
1096         case Opt_vers_4_0:
1097                 mnt->version = 4;
1098                 mnt->minorversion = 0;
1099                 break;
1100         case Opt_vers_4_1:
1101                 mnt->version = 4;
1102                 mnt->minorversion = 1;
1103                 break;
1104         case Opt_vers_4_2:
1105                 mnt->version = 4;
1106                 mnt->minorversion = 2;
1107                 break;
1108         default:
1109                 return 0;
1110         }
1111         return 1;
1112 }
1113
1114 static int nfs_get_option_str(substring_t args[], char **option)
1115 {
1116         kfree(*option);
1117         *option = match_strdup(args);
1118         return !*option;
1119 }
1120
1121 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1122 {
1123         int rc;
1124         char *string;
1125
1126         string = match_strdup(args);
1127         if (string == NULL)
1128                 return -ENOMEM;
1129         rc = kstrtoul(string, 10, option);
1130         kfree(string);
1131
1132         return rc;
1133 }
1134
1135 /*
1136  * Error-check and convert a string of mount options from user space into
1137  * a data structure.  The whole mount string is processed; bad options are
1138  * skipped as they are encountered.  If there were no errors, return 1;
1139  * otherwise return 0 (zero).
1140  */
1141 static int nfs_parse_mount_options(char *raw,
1142                                    struct nfs_parsed_mount_data *mnt)
1143 {
1144         char *p, *string, *secdata;
1145         int rc, sloppy = 0, invalid_option = 0;
1146         unsigned short protofamily = AF_UNSPEC;
1147         unsigned short mountfamily = AF_UNSPEC;
1148
1149         if (!raw) {
1150                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1151                 return 1;
1152         }
1153         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1154
1155         secdata = alloc_secdata();
1156         if (!secdata)
1157                 goto out_nomem;
1158
1159         rc = security_sb_copy_data(raw, secdata);
1160         if (rc)
1161                 goto out_security_failure;
1162
1163         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1164         if (rc)
1165                 goto out_security_failure;
1166
1167         free_secdata(secdata);
1168
1169         while ((p = strsep(&raw, ",")) != NULL) {
1170                 substring_t args[MAX_OPT_ARGS];
1171                 unsigned long option;
1172                 int token;
1173
1174                 if (!*p)
1175                         continue;
1176
1177                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1178
1179                 token = match_token(p, nfs_mount_option_tokens, args);
1180                 switch (token) {
1181
1182                 /*
1183                  * boolean options:  foo/nofoo
1184                  */
1185                 case Opt_soft:
1186                         mnt->flags |= NFS_MOUNT_SOFT;
1187                         break;
1188                 case Opt_hard:
1189                         mnt->flags &= ~NFS_MOUNT_SOFT;
1190                         break;
1191                 case Opt_posix:
1192                         mnt->flags |= NFS_MOUNT_POSIX;
1193                         break;
1194                 case Opt_noposix:
1195                         mnt->flags &= ~NFS_MOUNT_POSIX;
1196                         break;
1197                 case Opt_cto:
1198                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1199                         break;
1200                 case Opt_nocto:
1201                         mnt->flags |= NFS_MOUNT_NOCTO;
1202                         break;
1203                 case Opt_ac:
1204                         mnt->flags &= ~NFS_MOUNT_NOAC;
1205                         break;
1206                 case Opt_noac:
1207                         mnt->flags |= NFS_MOUNT_NOAC;
1208                         break;
1209                 case Opt_lock:
1210                         mnt->flags &= ~NFS_MOUNT_NONLM;
1211                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1212                                         NFS_MOUNT_LOCAL_FCNTL);
1213                         break;
1214                 case Opt_nolock:
1215                         mnt->flags |= NFS_MOUNT_NONLM;
1216                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1217                                        NFS_MOUNT_LOCAL_FCNTL);
1218                         break;
1219                 case Opt_udp:
1220                         mnt->flags &= ~NFS_MOUNT_TCP;
1221                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1222                         break;
1223                 case Opt_tcp:
1224                         mnt->flags |= NFS_MOUNT_TCP;
1225                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1226                         break;
1227                 case Opt_rdma:
1228                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1229                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1230                         xprt_load_transport(p);
1231                         break;
1232                 case Opt_acl:
1233                         mnt->flags &= ~NFS_MOUNT_NOACL;
1234                         break;
1235                 case Opt_noacl:
1236                         mnt->flags |= NFS_MOUNT_NOACL;
1237                         break;
1238                 case Opt_rdirplus:
1239                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1240                         break;
1241                 case Opt_nordirplus:
1242                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1243                         break;
1244                 case Opt_sharecache:
1245                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1246                         break;
1247                 case Opt_nosharecache:
1248                         mnt->flags |= NFS_MOUNT_UNSHARED;
1249                         break;
1250                 case Opt_resvport:
1251                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1252                         break;
1253                 case Opt_noresvport:
1254                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1255                         break;
1256                 case Opt_fscache:
1257                         mnt->options |= NFS_OPTION_FSCACHE;
1258                         kfree(mnt->fscache_uniq);
1259                         mnt->fscache_uniq = NULL;
1260                         break;
1261                 case Opt_nofscache:
1262                         mnt->options &= ~NFS_OPTION_FSCACHE;
1263                         kfree(mnt->fscache_uniq);
1264                         mnt->fscache_uniq = NULL;
1265                         break;
1266                 case Opt_migration:
1267                         mnt->options |= NFS_OPTION_MIGRATION;
1268                         break;
1269                 case Opt_nomigration:
1270                         mnt->options &= NFS_OPTION_MIGRATION;
1271                         break;
1272
1273                 /*
1274                  * options that take numeric values
1275                  */
1276                 case Opt_port:
1277                         if (nfs_get_option_ul(args, &option) ||
1278                             option > USHRT_MAX)
1279                                 goto out_invalid_value;
1280                         mnt->nfs_server.port = option;
1281                         break;
1282                 case Opt_rsize:
1283                         if (nfs_get_option_ul(args, &option))
1284                                 goto out_invalid_value;
1285                         mnt->rsize = option;
1286                         break;
1287                 case Opt_wsize:
1288                         if (nfs_get_option_ul(args, &option))
1289                                 goto out_invalid_value;
1290                         mnt->wsize = option;
1291                         break;
1292                 case Opt_bsize:
1293                         if (nfs_get_option_ul(args, &option))
1294                                 goto out_invalid_value;
1295                         mnt->bsize = option;
1296                         break;
1297                 case Opt_timeo:
1298                         if (nfs_get_option_ul(args, &option) || option == 0)
1299                                 goto out_invalid_value;
1300                         mnt->timeo = option;
1301                         break;
1302                 case Opt_retrans:
1303                         if (nfs_get_option_ul(args, &option) || option == 0)
1304                                 goto out_invalid_value;
1305                         mnt->retrans = option;
1306                         break;
1307                 case Opt_acregmin:
1308                         if (nfs_get_option_ul(args, &option))
1309                                 goto out_invalid_value;
1310                         mnt->acregmin = option;
1311                         break;
1312                 case Opt_acregmax:
1313                         if (nfs_get_option_ul(args, &option))
1314                                 goto out_invalid_value;
1315                         mnt->acregmax = option;
1316                         break;
1317                 case Opt_acdirmin:
1318                         if (nfs_get_option_ul(args, &option))
1319                                 goto out_invalid_value;
1320                         mnt->acdirmin = option;
1321                         break;
1322                 case Opt_acdirmax:
1323                         if (nfs_get_option_ul(args, &option))
1324                                 goto out_invalid_value;
1325                         mnt->acdirmax = option;
1326                         break;
1327                 case Opt_actimeo:
1328                         if (nfs_get_option_ul(args, &option))
1329                                 goto out_invalid_value;
1330                         mnt->acregmin = mnt->acregmax =
1331                         mnt->acdirmin = mnt->acdirmax = option;
1332                         break;
1333                 case Opt_namelen:
1334                         if (nfs_get_option_ul(args, &option))
1335                                 goto out_invalid_value;
1336                         mnt->namlen = option;
1337                         break;
1338                 case Opt_mountport:
1339                         if (nfs_get_option_ul(args, &option) ||
1340                             option > USHRT_MAX)
1341                                 goto out_invalid_value;
1342                         mnt->mount_server.port = option;
1343                         break;
1344                 case Opt_mountvers:
1345                         if (nfs_get_option_ul(args, &option) ||
1346                             option < NFS_MNT_VERSION ||
1347                             option > NFS_MNT3_VERSION)
1348                                 goto out_invalid_value;
1349                         mnt->mount_server.version = option;
1350                         break;
1351                 case Opt_minorversion:
1352                         if (nfs_get_option_ul(args, &option))
1353                                 goto out_invalid_value;
1354                         if (option > NFS4_MAX_MINOR_VERSION)
1355                                 goto out_invalid_value;
1356                         mnt->minorversion = option;
1357                         break;
1358
1359                 /*
1360                  * options that take text values
1361                  */
1362                 case Opt_nfsvers:
1363                         string = match_strdup(args);
1364                         if (string == NULL)
1365                                 goto out_nomem;
1366                         rc = nfs_parse_version_string(string, mnt, args);
1367                         kfree(string);
1368                         if (!rc)
1369                                 goto out_invalid_value;
1370                         break;
1371                 case Opt_sec:
1372                         string = match_strdup(args);
1373                         if (string == NULL)
1374                                 goto out_nomem;
1375                         rc = nfs_parse_security_flavors(string, mnt);
1376                         kfree(string);
1377                         if (!rc) {
1378                                 dfprintk(MOUNT, "NFS:   unrecognized "
1379                                                 "security flavor\n");
1380                                 return 0;
1381                         }
1382                         break;
1383                 case Opt_proto:
1384                         string = match_strdup(args);
1385                         if (string == NULL)
1386                                 goto out_nomem;
1387                         token = match_token(string,
1388                                             nfs_xprt_protocol_tokens, args);
1389
1390                         protofamily = AF_INET;
1391                         switch (token) {
1392                         case Opt_xprt_udp6:
1393                                 protofamily = AF_INET6;
1394                         case Opt_xprt_udp:
1395                                 mnt->flags &= ~NFS_MOUNT_TCP;
1396                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1397                                 break;
1398                         case Opt_xprt_tcp6:
1399                                 protofamily = AF_INET6;
1400                         case Opt_xprt_tcp:
1401                                 mnt->flags |= NFS_MOUNT_TCP;
1402                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1403                                 break;
1404                         case Opt_xprt_rdma:
1405                                 /* vector side protocols to TCP */
1406                                 mnt->flags |= NFS_MOUNT_TCP;
1407                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1408                                 xprt_load_transport(string);
1409                                 break;
1410                         default:
1411                                 dfprintk(MOUNT, "NFS:   unrecognized "
1412                                                 "transport protocol\n");
1413                                 kfree(string);
1414                                 return 0;
1415                         }
1416                         kfree(string);
1417                         break;
1418                 case Opt_mountproto:
1419                         string = match_strdup(args);
1420                         if (string == NULL)
1421                                 goto out_nomem;
1422                         token = match_token(string,
1423                                             nfs_xprt_protocol_tokens, args);
1424                         kfree(string);
1425
1426                         mountfamily = AF_INET;
1427                         switch (token) {
1428                         case Opt_xprt_udp6:
1429                                 mountfamily = AF_INET6;
1430                         case Opt_xprt_udp:
1431                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1432                                 break;
1433                         case Opt_xprt_tcp6:
1434                                 mountfamily = AF_INET6;
1435                         case Opt_xprt_tcp:
1436                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1437                                 break;
1438                         case Opt_xprt_rdma: /* not used for side protocols */
1439                         default:
1440                                 dfprintk(MOUNT, "NFS:   unrecognized "
1441                                                 "transport protocol\n");
1442                                 return 0;
1443                         }
1444                         break;
1445                 case Opt_addr:
1446                         string = match_strdup(args);
1447                         if (string == NULL)
1448                                 goto out_nomem;
1449                         mnt->nfs_server.addrlen =
1450                                 rpc_pton(mnt->net, string, strlen(string),
1451                                         (struct sockaddr *)
1452                                         &mnt->nfs_server.address,
1453                                         sizeof(mnt->nfs_server.address));
1454                         kfree(string);
1455                         if (mnt->nfs_server.addrlen == 0)
1456                                 goto out_invalid_address;
1457                         break;
1458                 case Opt_clientaddr:
1459                         if (nfs_get_option_str(args, &mnt->client_address))
1460                                 goto out_nomem;
1461                         break;
1462                 case Opt_mounthost:
1463                         if (nfs_get_option_str(args,
1464                                                &mnt->mount_server.hostname))
1465                                 goto out_nomem;
1466                         break;
1467                 case Opt_mountaddr:
1468                         string = match_strdup(args);
1469                         if (string == NULL)
1470                                 goto out_nomem;
1471                         mnt->mount_server.addrlen =
1472                                 rpc_pton(mnt->net, string, strlen(string),
1473                                         (struct sockaddr *)
1474                                         &mnt->mount_server.address,
1475                                         sizeof(mnt->mount_server.address));
1476                         kfree(string);
1477                         if (mnt->mount_server.addrlen == 0)
1478                                 goto out_invalid_address;
1479                         break;
1480                 case Opt_lookupcache:
1481                         string = match_strdup(args);
1482                         if (string == NULL)
1483                                 goto out_nomem;
1484                         token = match_token(string,
1485                                         nfs_lookupcache_tokens, args);
1486                         kfree(string);
1487                         switch (token) {
1488                                 case Opt_lookupcache_all:
1489                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1490                                         break;
1491                                 case Opt_lookupcache_positive:
1492                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1493                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1494                                         break;
1495                                 case Opt_lookupcache_none:
1496                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1497                                         break;
1498                                 default:
1499                                         dfprintk(MOUNT, "NFS:   invalid "
1500                                                         "lookupcache argument\n");
1501                                         return 0;
1502                         };
1503                         break;
1504                 case Opt_fscache_uniq:
1505                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1506                                 goto out_nomem;
1507                         mnt->options |= NFS_OPTION_FSCACHE;
1508                         break;
1509                 case Opt_local_lock:
1510                         string = match_strdup(args);
1511                         if (string == NULL)
1512                                 goto out_nomem;
1513                         token = match_token(string, nfs_local_lock_tokens,
1514                                         args);
1515                         kfree(string);
1516                         switch (token) {
1517                         case Opt_local_lock_all:
1518                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1519                                                NFS_MOUNT_LOCAL_FCNTL);
1520                                 break;
1521                         case Opt_local_lock_flock:
1522                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1523                                 break;
1524                         case Opt_local_lock_posix:
1525                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1526                                 break;
1527                         case Opt_local_lock_none:
1528                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1529                                                 NFS_MOUNT_LOCAL_FCNTL);
1530                                 break;
1531                         default:
1532                                 dfprintk(MOUNT, "NFS:   invalid "
1533                                                 "local_lock argument\n");
1534                                 return 0;
1535                         };
1536                         break;
1537
1538                 /*
1539                  * Special options
1540                  */
1541                 case Opt_sloppy:
1542                         sloppy = 1;
1543                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1544                         break;
1545                 case Opt_userspace:
1546                 case Opt_deprecated:
1547                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1548                                         "'%s'\n", p);
1549                         break;
1550
1551                 default:
1552                         invalid_option = 1;
1553                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1554                                         "'%s'\n", p);
1555                 }
1556         }
1557
1558         if (!sloppy && invalid_option)
1559                 return 0;
1560
1561         if (mnt->minorversion && mnt->version != 4)
1562                 goto out_minorversion_mismatch;
1563
1564         if (mnt->options & NFS_OPTION_MIGRATION &&
1565             mnt->version != 4 && mnt->minorversion != 0)
1566                 goto out_migration_misuse;
1567
1568         /*
1569          * verify that any proto=/mountproto= options match the address
1570          * families in the addr=/mountaddr= options.
1571          */
1572         if (protofamily != AF_UNSPEC &&
1573             protofamily != mnt->nfs_server.address.ss_family)
1574                 goto out_proto_mismatch;
1575
1576         if (mountfamily != AF_UNSPEC) {
1577                 if (mnt->mount_server.addrlen) {
1578                         if (mountfamily != mnt->mount_server.address.ss_family)
1579                                 goto out_mountproto_mismatch;
1580                 } else {
1581                         if (mountfamily != mnt->nfs_server.address.ss_family)
1582                                 goto out_mountproto_mismatch;
1583                 }
1584         }
1585
1586         return 1;
1587
1588 out_mountproto_mismatch:
1589         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1590                          "option\n");
1591         return 0;
1592 out_proto_mismatch:
1593         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1594         return 0;
1595 out_invalid_address:
1596         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1597         return 0;
1598 out_invalid_value:
1599         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1600         return 0;
1601 out_minorversion_mismatch:
1602         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1603                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1604         return 0;
1605 out_migration_misuse:
1606         printk(KERN_INFO
1607                 "NFS: 'migration' not supported for this NFS version\n");
1608         return 0;
1609 out_nomem:
1610         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1611         return 0;
1612 out_security_failure:
1613         free_secdata(secdata);
1614         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1615         return 0;
1616 }
1617
1618 /*
1619  * Ensure that the specified authtype in args->auth_info is supported by
1620  * the server. Returns 0 if it's ok, and -EACCES if not.
1621  */
1622 static int nfs_verify_authflavor(struct nfs_parsed_mount_data *args,
1623                         rpc_authflavor_t *server_authlist, unsigned int count)
1624 {
1625         unsigned int i;
1626
1627         /*
1628          * If the sec= mount option is used, the specified flavor or AUTH_NULL
1629          * must be in the list returned by the server.
1630          *
1631          * AUTH_NULL has a special meaning when it's in the server list - it
1632          * means that the server will ignore the rpc creds, so any flavor
1633          * can be used.
1634          */
1635         for (i = 0; i < count; i++) {
1636                 if (args->auth_info.flavors[0] == server_authlist[i] ||
1637                     server_authlist[i] == RPC_AUTH_NULL)
1638                         goto out;
1639         }
1640
1641         dfprintk(MOUNT, "NFS: auth flavor %u not supported by server\n",
1642                 args->auth_info.flavors[0]);
1643         return -EACCES;
1644
1645 out:
1646         args->selected_flavor = args->auth_info.flavors[0];
1647         dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
1648         return 0;
1649 }
1650
1651 /*
1652  * Use the remote server's MOUNT service to request the NFS file handle
1653  * corresponding to the provided path.
1654  */
1655 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1656                              struct nfs_fh *root_fh,
1657                              rpc_authflavor_t *server_authlist,
1658                              unsigned int *server_authlist_len)
1659 {
1660         struct nfs_mount_request request = {
1661                 .sap            = (struct sockaddr *)
1662                                                 &args->mount_server.address,
1663                 .dirpath        = args->nfs_server.export_path,
1664                 .protocol       = args->mount_server.protocol,
1665                 .fh             = root_fh,
1666                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1667                 .auth_flav_len  = server_authlist_len,
1668                 .auth_flavs     = server_authlist,
1669                 .net            = args->net,
1670         };
1671         int status;
1672
1673         if (args->mount_server.version == 0) {
1674                 switch (args->version) {
1675                         default:
1676                                 args->mount_server.version = NFS_MNT3_VERSION;
1677                                 break;
1678                         case 2:
1679                                 args->mount_server.version = NFS_MNT_VERSION;
1680                 }
1681         }
1682         request.version = args->mount_server.version;
1683
1684         if (args->mount_server.hostname)
1685                 request.hostname = args->mount_server.hostname;
1686         else
1687                 request.hostname = args->nfs_server.hostname;
1688
1689         /*
1690          * Construct the mount server's address.
1691          */
1692         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1693                 memcpy(request.sap, &args->nfs_server.address,
1694                        args->nfs_server.addrlen);
1695                 args->mount_server.addrlen = args->nfs_server.addrlen;
1696         }
1697         request.salen = args->mount_server.addrlen;
1698         nfs_set_port(request.sap, &args->mount_server.port, 0);
1699
1700         /*
1701          * Now ask the mount server to map our export path
1702          * to a file handle.
1703          */
1704         status = nfs_mount(&request);
1705         if (status != 0) {
1706                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1707                                 request.hostname, status);
1708                 return status;
1709         }
1710
1711         return 0;
1712 }
1713
1714 static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1715                                         struct nfs_subversion *nfs_mod)
1716 {
1717         int status;
1718         unsigned int i;
1719         bool tried_auth_unix = false;
1720         bool auth_null_in_list = false;
1721         struct nfs_server *server = ERR_PTR(-EACCES);
1722         struct nfs_parsed_mount_data *args = mount_info->parsed;
1723         rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1724         unsigned int authlist_len = ARRAY_SIZE(authlist);
1725
1726         status = nfs_request_mount(args, mount_info->mntfh, authlist,
1727                                         &authlist_len);
1728         if (status)
1729                 return ERR_PTR(status);
1730
1731         /*
1732          * Was a sec= authflavor specified in the options? First, verify
1733          * whether the server supports it, and then just try to use it if so.
1734          */
1735         if (args->auth_info.flavor_len > 0) {
1736                 status = nfs_verify_authflavor(args, authlist, authlist_len);
1737                 dfprintk(MOUNT, "NFS: using auth flavor %u\n",
1738                          args->selected_flavor);
1739                 if (status)
1740                         return ERR_PTR(status);
1741                 return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1742         }
1743
1744         /*
1745          * No sec= option was provided. RFC 2623, section 2.7 suggests we
1746          * SHOULD prefer the flavor listed first. However, some servers list
1747          * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1748          */
1749         for (i = 0; i < authlist_len; ++i) {
1750                 rpc_authflavor_t flavor;
1751                 struct rpcsec_gss_info info;
1752
1753                 flavor = authlist[i];
1754                 switch (flavor) {
1755                 case RPC_AUTH_UNIX:
1756                         tried_auth_unix = true;
1757                         break;
1758                 case RPC_AUTH_NULL:
1759                         auth_null_in_list = true;
1760                         continue;
1761                 default:
1762                         if (rpcauth_get_gssinfo(flavor, &info) != 0)
1763                                 continue;
1764                         /* Fallthrough */
1765                 }
1766                 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1767                 args->selected_flavor = flavor;
1768                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1769                 if (!IS_ERR(server))
1770                         return server;
1771         }
1772
1773         /*
1774          * Nothing we tried so far worked. At this point, give up if we've
1775          * already tried AUTH_UNIX or if the server's list doesn't contain
1776          * AUTH_NULL
1777          */
1778         if (tried_auth_unix || !auth_null_in_list)
1779                 return server;
1780
1781         /* Last chance! Try AUTH_UNIX */
1782         dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1783         args->selected_flavor = RPC_AUTH_UNIX;
1784         return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1785 }
1786
1787 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1788                              struct nfs_mount_info *mount_info,
1789                              struct nfs_subversion *nfs_mod)
1790 {
1791         struct nfs_server *server;
1792
1793         if (mount_info->parsed->need_mount)
1794                 server = nfs_try_mount_request(mount_info, nfs_mod);
1795         else
1796                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1797
1798         if (IS_ERR(server))
1799                 return ERR_CAST(server);
1800
1801         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1802 }
1803 EXPORT_SYMBOL_GPL(nfs_try_mount);
1804
1805 /*
1806  * Split "dev_name" into "hostname:export_path".
1807  *
1808  * The leftmost colon demarks the split between the server's hostname
1809  * and the export path.  If the hostname starts with a left square
1810  * bracket, then it may contain colons.
1811  *
1812  * Note: caller frees hostname and export path, even on error.
1813  */
1814 static int nfs_parse_devname(const char *dev_name,
1815                              char **hostname, size_t maxnamlen,
1816                              char **export_path, size_t maxpathlen)
1817 {
1818         size_t len;
1819         char *end;
1820
1821         /* Is the host name protected with square brakcets? */
1822         if (*dev_name == '[') {
1823                 end = strchr(++dev_name, ']');
1824                 if (end == NULL || end[1] != ':')
1825                         goto out_bad_devname;
1826
1827                 len = end - dev_name;
1828                 end++;
1829         } else {
1830                 char *comma;
1831
1832                 end = strchr(dev_name, ':');
1833                 if (end == NULL)
1834                         goto out_bad_devname;
1835                 len = end - dev_name;
1836
1837                 /* kill possible hostname list: not supported */
1838                 comma = strchr(dev_name, ',');
1839                 if (comma != NULL && comma < end)
1840                         *comma = 0;
1841         }
1842
1843         if (len > maxnamlen)
1844                 goto out_hostname;
1845
1846         /* N.B. caller will free nfs_server.hostname in all cases */
1847         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1848         if (*hostname == NULL)
1849                 goto out_nomem;
1850         len = strlen(++end);
1851         if (len > maxpathlen)
1852                 goto out_path;
1853         *export_path = kstrndup(end, len, GFP_KERNEL);
1854         if (!*export_path)
1855                 goto out_nomem;
1856
1857         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1858         return 0;
1859
1860 out_bad_devname:
1861         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1862         return -EINVAL;
1863
1864 out_nomem:
1865         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1866         return -ENOMEM;
1867
1868 out_hostname:
1869         dfprintk(MOUNT, "NFS: server hostname too long\n");
1870         return -ENAMETOOLONG;
1871
1872 out_path:
1873         dfprintk(MOUNT, "NFS: export pathname too long\n");
1874         return -ENAMETOOLONG;
1875 }
1876
1877 /*
1878  * Validate the NFS2/NFS3 mount data
1879  * - fills in the mount root filehandle
1880  *
1881  * For option strings, user space handles the following behaviors:
1882  *
1883  * + DNS: mapping server host name to IP address ("addr=" option)
1884  *
1885  * + failure mode: how to behave if a mount request can't be handled
1886  *   immediately ("fg/bg" option)
1887  *
1888  * + retry: how often to retry a mount request ("retry=" option)
1889  *
1890  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1891  *   mountproto=tcp after mountproto=udp, and so on
1892  */
1893 static int nfs23_validate_mount_data(void *options,
1894                                      struct nfs_parsed_mount_data *args,
1895                                      struct nfs_fh *mntfh,
1896                                      const char *dev_name)
1897 {
1898         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1899         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1900         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1901
1902         if (data == NULL)
1903                 goto out_no_data;
1904
1905         args->version = NFS_DEFAULT_VERSION;
1906         switch (data->version) {
1907         case 1:
1908                 data->namlen = 0;
1909         case 2:
1910                 data->bsize = 0;
1911         case 3:
1912                 if (data->flags & NFS_MOUNT_VER3)
1913                         goto out_no_v3;
1914                 data->root.size = NFS2_FHSIZE;
1915                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1916                 /* Turn off security negotiation */
1917                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
1918         case 4:
1919                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1920                         goto out_no_sec;
1921         case 5:
1922                 memset(data->context, 0, sizeof(data->context));
1923         case 6:
1924                 if (data->flags & NFS_MOUNT_VER3) {
1925                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1926                                 goto out_invalid_fh;
1927                         mntfh->size = data->root.size;
1928                         args->version = 3;
1929                 } else {
1930                         mntfh->size = NFS2_FHSIZE;
1931                         args->version = 2;
1932                 }
1933
1934
1935                 memcpy(mntfh->data, data->root.data, mntfh->size);
1936                 if (mntfh->size < sizeof(mntfh->data))
1937                         memset(mntfh->data + mntfh->size, 0,
1938                                sizeof(mntfh->data) - mntfh->size);
1939
1940                 /*
1941                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1942                  * can deal with.
1943                  */
1944                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1945                 args->flags             |= extra_flags;
1946                 args->rsize             = data->rsize;
1947                 args->wsize             = data->wsize;
1948                 args->timeo             = data->timeo;
1949                 args->retrans           = data->retrans;
1950                 args->acregmin          = data->acregmin;
1951                 args->acregmax          = data->acregmax;
1952                 args->acdirmin          = data->acdirmin;
1953                 args->acdirmax          = data->acdirmax;
1954                 args->need_mount        = false;
1955
1956                 memcpy(sap, &data->addr, sizeof(data->addr));
1957                 args->nfs_server.addrlen = sizeof(data->addr);
1958                 args->nfs_server.port = ntohs(data->addr.sin_port);
1959                 if (!nfs_verify_server_address(sap))
1960                         goto out_no_address;
1961
1962                 if (!(data->flags & NFS_MOUNT_TCP))
1963                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1964                 /* N.B. caller will free nfs_server.hostname in all cases */
1965                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1966                 args->namlen            = data->namlen;
1967                 args->bsize             = data->bsize;
1968
1969                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1970                         args->selected_flavor = data->pseudoflavor;
1971                 else
1972                         args->selected_flavor = RPC_AUTH_UNIX;
1973                 if (!args->nfs_server.hostname)
1974                         goto out_nomem;
1975
1976                 if (!(data->flags & NFS_MOUNT_NONLM))
1977                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1978                                          NFS_MOUNT_LOCAL_FCNTL);
1979                 else
1980                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1981                                         NFS_MOUNT_LOCAL_FCNTL);
1982                 /*
1983                  * The legacy version 6 binary mount data from userspace has a
1984                  * field used only to transport selinux information into the
1985                  * the kernel.  To continue to support that functionality we
1986                  * have a touch of selinux knowledge here in the NFS code. The
1987                  * userspace code converted context=blah to just blah so we are
1988                  * converting back to the full string selinux understands.
1989                  */
1990                 if (data->context[0]){
1991 #ifdef CONFIG_SECURITY_SELINUX
1992                         int rc;
1993                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1994                         if (!opts_str)
1995                                 return -ENOMEM;
1996                         strcpy(opts_str, "context=");
1997                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1998                         strcat(opts_str, &data->context[0]);
1999                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
2000                         kfree(opts_str);
2001                         if (rc)
2002                                 return rc;
2003 #else
2004                         return -EINVAL;
2005 #endif
2006                 }
2007
2008                 break;
2009         default:
2010                 return NFS_TEXT_DATA;
2011         }
2012
2013 #if !IS_ENABLED(CONFIG_NFS_V3)
2014         if (args->version == 3)
2015                 goto out_v3_not_compiled;
2016 #endif /* !CONFIG_NFS_V3 */
2017
2018         return 0;
2019
2020 out_no_data:
2021         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2022         return -EINVAL;
2023
2024 out_no_v3:
2025         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2026                  data->version);
2027         return -EINVAL;
2028
2029 out_no_sec:
2030         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2031         return -EINVAL;
2032
2033 #if !IS_ENABLED(CONFIG_NFS_V3)
2034 out_v3_not_compiled:
2035         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
2036         return -EPROTONOSUPPORT;
2037 #endif /* !CONFIG_NFS_V3 */
2038
2039 out_nomem:
2040         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2041         return -ENOMEM;
2042
2043 out_no_address:
2044         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2045         return -EINVAL;
2046
2047 out_invalid_fh:
2048         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2049         return -EINVAL;
2050 }
2051
2052 #if IS_ENABLED(CONFIG_NFS_V4)
2053 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2054                                    void *options,
2055                                    struct nfs_parsed_mount_data *args,
2056                                    struct nfs_fh *mntfh,
2057                                    const char *dev_name)
2058 {
2059         if (fs_type == &nfs_fs_type)
2060                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2061         return nfs4_validate_mount_data(options, args, dev_name);
2062 }
2063 #else
2064 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2065                                    void *options,
2066                                    struct nfs_parsed_mount_data *args,
2067                                    struct nfs_fh *mntfh,
2068                                    const char *dev_name)
2069 {
2070         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2071 }
2072 #endif
2073
2074 static int nfs_validate_text_mount_data(void *options,
2075                                         struct nfs_parsed_mount_data *args,
2076                                         const char *dev_name)
2077 {
2078         int port = 0;
2079         int max_namelen = PAGE_SIZE;
2080         int max_pathlen = NFS_MAXPATHLEN;
2081         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2082
2083         if (nfs_parse_mount_options((char *)options, args) == 0)
2084                 return -EINVAL;
2085
2086         if (!nfs_verify_server_address(sap))
2087                 goto out_no_address;
2088
2089         if (args->version == 4) {
2090 #if IS_ENABLED(CONFIG_NFS_V4)
2091                 port = NFS_PORT;
2092                 max_namelen = NFS4_MAXNAMLEN;
2093                 max_pathlen = NFS4_MAXPATHLEN;
2094                 nfs_validate_transport_protocol(args);
2095                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2096                         goto out_invalid_transport_udp;
2097                 nfs4_validate_mount_flags(args);
2098 #else
2099                 goto out_v4_not_compiled;
2100 #endif /* CONFIG_NFS_V4 */
2101         } else
2102                 nfs_set_mount_transport_protocol(args);
2103
2104         nfs_set_port(sap, &args->nfs_server.port, port);
2105
2106         if (args->auth_info.flavor_len > 1)
2107                 goto out_bad_auth;
2108
2109         return nfs_parse_devname(dev_name,
2110                                    &args->nfs_server.hostname,
2111                                    max_namelen,
2112                                    &args->nfs_server.export_path,
2113                                    max_pathlen);
2114
2115 #if !IS_ENABLED(CONFIG_NFS_V4)
2116 out_v4_not_compiled:
2117         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2118         return -EPROTONOSUPPORT;
2119 #else
2120 out_invalid_transport_udp:
2121         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2122         return -EINVAL;
2123 #endif /* !CONFIG_NFS_V4 */
2124
2125 out_no_address:
2126         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2127         return -EINVAL;
2128
2129 out_bad_auth:
2130         dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
2131         return -EINVAL;
2132 }
2133
2134 static int
2135 nfs_compare_remount_data(struct nfs_server *nfss,
2136                          struct nfs_parsed_mount_data *data)
2137 {
2138         if (data->flags != nfss->flags ||
2139             data->rsize != nfss->rsize ||
2140             data->wsize != nfss->wsize ||
2141             data->version != nfss->nfs_client->rpc_ops->version ||
2142             data->minorversion != nfss->nfs_client->cl_minorversion ||
2143             data->retrans != nfss->client->cl_timeout->to_retries ||
2144             data->selected_flavor != nfss->client->cl_auth->au_flavor ||
2145             data->acregmin != nfss->acregmin / HZ ||
2146             data->acregmax != nfss->acregmax / HZ ||
2147             data->acdirmin != nfss->acdirmin / HZ ||
2148             data->acdirmax != nfss->acdirmax / HZ ||
2149             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2150             data->nfs_server.port != nfss->port ||
2151             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2152             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2153                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2154                 return -EINVAL;
2155
2156         return 0;
2157 }
2158
2159 int
2160 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2161 {
2162         int error;
2163         struct nfs_server *nfss = sb->s_fs_info;
2164         struct nfs_parsed_mount_data *data;
2165         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2166         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2167         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2168
2169         /*
2170          * Userspace mount programs that send binary options generally send
2171          * them populated with default values. We have no way to know which
2172          * ones were explicitly specified. Fall back to legacy behavior and
2173          * just return success.
2174          */
2175         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2176             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2177                                            options->version <= 6))))
2178                 return 0;
2179
2180         data = kzalloc(sizeof(*data), GFP_KERNEL);
2181         if (data == NULL)
2182                 return -ENOMEM;
2183
2184         /* fill out struct with values from existing mount */
2185         data->flags = nfss->flags;
2186         data->rsize = nfss->rsize;
2187         data->wsize = nfss->wsize;
2188         data->retrans = nfss->client->cl_timeout->to_retries;
2189         data->selected_flavor = nfss->client->cl_auth->au_flavor;
2190         data->auth_info.flavors[0] = nfss->client->cl_auth->au_flavor;
2191         data->auth_info.flavor_len = 1;
2192         data->acregmin = nfss->acregmin / HZ;
2193         data->acregmax = nfss->acregmax / HZ;
2194         data->acdirmin = nfss->acdirmin / HZ;
2195         data->acdirmax = nfss->acdirmax / HZ;
2196         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2197         data->nfs_server.port = nfss->port;
2198         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2199         data->version = nfsvers;
2200         data->minorversion = nfss->nfs_client->cl_minorversion;
2201         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2202                 data->nfs_server.addrlen);
2203
2204         /* overwrite those values with any that were specified */
2205         error = -EINVAL;
2206         if (!nfs_parse_mount_options((char *)options, data))
2207                 goto out;
2208
2209         /*
2210          * noac is a special case. It implies -o sync, but that's not
2211          * necessarily reflected in the mtab options. do_remount_sb
2212          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2213          * remount options, so we have to explicitly reset it.
2214          */
2215         if (data->flags & NFS_MOUNT_NOAC)
2216                 *flags |= MS_SYNCHRONOUS;
2217
2218         /* compare new mount options with old ones */
2219         error = nfs_compare_remount_data(nfss, data);
2220 out:
2221         kfree(data);
2222         return error;
2223 }
2224 EXPORT_SYMBOL_GPL(nfs_remount);
2225
2226 /*
2227  * Initialise the common bits of the superblock
2228  */
2229 inline void nfs_initialise_sb(struct super_block *sb)
2230 {
2231         struct nfs_server *server = NFS_SB(sb);
2232
2233         sb->s_magic = NFS_SUPER_MAGIC;
2234
2235         /* We probably want something more informative here */
2236         snprintf(sb->s_id, sizeof(sb->s_id),
2237                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2238
2239         if (sb->s_blocksize == 0)
2240                 sb->s_blocksize = nfs_block_bits(server->wsize,
2241                                                  &sb->s_blocksize_bits);
2242
2243         sb->s_bdi = &server->backing_dev_info;
2244
2245         nfs_super_set_maxbytes(sb, server->maxfilesize);
2246 }
2247
2248 /*
2249  * Finish setting up an NFS2/3 superblock
2250  */
2251 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2252 {
2253         struct nfs_parsed_mount_data *data = mount_info->parsed;
2254         struct nfs_server *server = NFS_SB(sb);
2255
2256         sb->s_blocksize_bits = 0;
2257         sb->s_blocksize = 0;
2258         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2259         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2260         if (data && data->bsize)
2261                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2262
2263         if (server->nfs_client->rpc_ops->version != 2) {
2264                 /* The VFS shouldn't apply the umask to mode bits. We will do
2265                  * so ourselves when necessary.
2266                  */
2267                 sb->s_flags |= MS_POSIXACL;
2268                 sb->s_time_gran = 1;
2269         }
2270
2271         nfs_initialise_sb(sb);
2272 }
2273 EXPORT_SYMBOL_GPL(nfs_fill_super);
2274
2275 /*
2276  * Finish setting up a cloned NFS2/3/4 superblock
2277  */
2278 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2279 {
2280         const struct super_block *old_sb = mount_info->cloned->sb;
2281         struct nfs_server *server = NFS_SB(sb);
2282
2283         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2284         sb->s_blocksize = old_sb->s_blocksize;
2285         sb->s_maxbytes = old_sb->s_maxbytes;
2286         sb->s_xattr = old_sb->s_xattr;
2287         sb->s_op = old_sb->s_op;
2288         sb->s_time_gran = 1;
2289
2290         if (server->nfs_client->rpc_ops->version != 2) {
2291                 /* The VFS shouldn't apply the umask to mode bits. We will do
2292                  * so ourselves when necessary.
2293                  */
2294                 sb->s_flags |= MS_POSIXACL;
2295         }
2296
2297         nfs_initialise_sb(sb);
2298 }
2299
2300 #define NFS_MOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
2301                 | NFS_MOUNT_SECURE \
2302                 | NFS_MOUNT_TCP \
2303                 | NFS_MOUNT_VER3 \
2304                 | NFS_MOUNT_KERBEROS \
2305                 | NFS_MOUNT_NONLM \
2306                 | NFS_MOUNT_BROKEN_SUID \
2307                 | NFS_MOUNT_STRICTLOCK \
2308                 | NFS_MOUNT_UNSHARED \
2309                 | NFS_MOUNT_NORESVPORT \
2310                 | NFS_MOUNT_LEGACY_INTERFACE)
2311
2312 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2313 {
2314         const struct nfs_server *a = s->s_fs_info;
2315         const struct rpc_clnt *clnt_a = a->client;
2316         const struct rpc_clnt *clnt_b = b->client;
2317
2318         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2319                 goto Ebusy;
2320         if (a->nfs_client != b->nfs_client)
2321                 goto Ebusy;
2322         if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
2323                 goto Ebusy;
2324         if (a->wsize != b->wsize)
2325                 goto Ebusy;
2326         if (a->rsize != b->rsize)
2327                 goto Ebusy;
2328         if (a->acregmin != b->acregmin)
2329                 goto Ebusy;
2330         if (a->acregmax != b->acregmax)
2331                 goto Ebusy;
2332         if (a->acdirmin != b->acdirmin)
2333                 goto Ebusy;
2334         if (a->acdirmax != b->acdirmax)
2335                 goto Ebusy;
2336         if (b->flags & NFS_MOUNT_SECFLAVOUR &&
2337            clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2338                 goto Ebusy;
2339         return 1;
2340 Ebusy:
2341         return 0;
2342 }
2343
2344 struct nfs_sb_mountdata {
2345         struct nfs_server *server;
2346         int mntflags;
2347 };
2348
2349 static int nfs_set_super(struct super_block *s, void *data)
2350 {
2351         struct nfs_sb_mountdata *sb_mntdata = data;
2352         struct nfs_server *server = sb_mntdata->server;
2353         int ret;
2354
2355         s->s_flags = sb_mntdata->mntflags;
2356         s->s_fs_info = server;
2357         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2358         ret = set_anon_super(s, server);
2359         if (ret == 0)
2360                 server->s_dev = s->s_dev;
2361         return ret;
2362 }
2363
2364 static int nfs_compare_super_address(struct nfs_server *server1,
2365                                      struct nfs_server *server2)
2366 {
2367         struct sockaddr *sap1, *sap2;
2368
2369         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2370         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2371
2372         if (sap1->sa_family != sap2->sa_family)
2373                 return 0;
2374
2375         switch (sap1->sa_family) {
2376         case AF_INET: {
2377                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2378                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2379                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2380                         return 0;
2381                 if (sin1->sin_port != sin2->sin_port)
2382                         return 0;
2383                 break;
2384         }
2385         case AF_INET6: {
2386                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2387                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2388                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2389                         return 0;
2390                 if (sin1->sin6_port != sin2->sin6_port)
2391                         return 0;
2392                 break;
2393         }
2394         default:
2395                 return 0;
2396         }
2397
2398         return 1;
2399 }
2400
2401 static int nfs_compare_super(struct super_block *sb, void *data)
2402 {
2403         struct nfs_sb_mountdata *sb_mntdata = data;
2404         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2405         int mntflags = sb_mntdata->mntflags;
2406
2407         if (!nfs_compare_super_address(old, server))
2408                 return 0;
2409         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2410         if (old->flags & NFS_MOUNT_UNSHARED)
2411                 return 0;
2412         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2413                 return 0;
2414         return nfs_compare_mount_options(sb, server, mntflags);
2415 }
2416
2417 #ifdef CONFIG_NFS_FSCACHE
2418 static void nfs_get_cache_cookie(struct super_block *sb,
2419                                  struct nfs_parsed_mount_data *parsed,
2420                                  struct nfs_clone_mount *cloned)
2421 {
2422         struct nfs_server *nfss = NFS_SB(sb);
2423         char *uniq = NULL;
2424         int ulen = 0;
2425
2426         nfss->fscache_key = NULL;
2427         nfss->fscache = NULL;
2428
2429         if (parsed) {
2430                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2431                         return;
2432                 if (parsed->fscache_uniq) {
2433                         uniq = parsed->fscache_uniq;
2434                         ulen = strlen(parsed->fscache_uniq);
2435                 }
2436         } else if (cloned) {
2437                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2438                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2439                         return;
2440                 if (mnt_s->fscache_key) {
2441                         uniq = mnt_s->fscache_key->key.uniquifier;
2442                         ulen = mnt_s->fscache_key->key.uniq_len;
2443                 };
2444         } else
2445                 return;
2446
2447         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2448 }
2449 #else
2450 static void nfs_get_cache_cookie(struct super_block *sb,
2451                                  struct nfs_parsed_mount_data *parsed,
2452                                  struct nfs_clone_mount *cloned)
2453 {
2454 }
2455 #endif
2456
2457 static int nfs_bdi_register(struct nfs_server *server)
2458 {
2459         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2460 }
2461
2462 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2463                         struct nfs_mount_info *mount_info)
2464 {
2465         int error;
2466         unsigned long kflags = 0, kflags_out = 0;
2467         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2468                 kflags |= SECURITY_LSM_NATIVE_LABELS;
2469
2470         error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
2471                                                 kflags, &kflags_out);
2472         if (error)
2473                 goto err;
2474
2475         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2476                 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2477                 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2478 err:
2479         return error;
2480 }
2481 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2482
2483 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2484                           struct nfs_mount_info *mount_info)
2485 {
2486         /* clone any lsm security options from the parent to the new sb */
2487         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2488                 return -ESTALE;
2489         return security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2490 }
2491 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2492
2493 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2494                                    int flags, const char *dev_name,
2495                                    struct nfs_mount_info *mount_info,
2496                                    struct nfs_subversion *nfs_mod)
2497 {
2498         struct super_block *s;
2499         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2500         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2501         struct nfs_sb_mountdata sb_mntdata = {
2502                 .mntflags = flags,
2503                 .server = server,
2504         };
2505         int error;
2506
2507         if (server->flags & NFS_MOUNT_UNSHARED)
2508                 compare_super = NULL;
2509
2510         /* -o noac implies -o sync */
2511         if (server->flags & NFS_MOUNT_NOAC)
2512                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2513
2514         if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
2515                 if (mount_info->cloned->sb->s_flags & MS_SYNCHRONOUS)
2516                         sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2517
2518         /* Get a superblock - note that we may end up sharing one that already exists */
2519         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2520         if (IS_ERR(s)) {
2521                 mntroot = ERR_CAST(s);
2522                 goto out_err_nosb;
2523         }
2524
2525         if (s->s_fs_info != server) {
2526                 nfs_free_server(server);
2527                 server = NULL;
2528         } else {
2529                 error = nfs_bdi_register(server);
2530                 if (error) {
2531                         mntroot = ERR_PTR(error);
2532                         goto error_splat_bdi;
2533                 }
2534                 server->super = s;
2535         }
2536
2537         if (!s->s_root) {
2538                 /* initial superblock/root creation */
2539                 mount_info->fill_super(s, mount_info);
2540                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2541         }
2542
2543         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2544         if (IS_ERR(mntroot))
2545                 goto error_splat_super;
2546
2547         error = mount_info->set_security(s, mntroot, mount_info);
2548         if (error)
2549                 goto error_splat_root;
2550
2551         s->s_flags |= MS_ACTIVE;
2552
2553 out:
2554         return mntroot;
2555
2556 out_err_nosb:
2557         nfs_free_server(server);
2558         goto out;
2559
2560 error_splat_root:
2561         dput(mntroot);
2562         mntroot = ERR_PTR(error);
2563 error_splat_super:
2564         if (server && !s->s_root)
2565                 bdi_unregister(&server->backing_dev_info);
2566 error_splat_bdi:
2567         deactivate_locked_super(s);
2568         goto out;
2569 }
2570 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2571
2572 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2573         int flags, const char *dev_name, void *raw_data)
2574 {
2575         struct nfs_mount_info mount_info = {
2576                 .fill_super = nfs_fill_super,
2577                 .set_security = nfs_set_sb_security,
2578         };
2579         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2580         struct nfs_subversion *nfs_mod;
2581         int error;
2582
2583         mount_info.parsed = nfs_alloc_parsed_mount_data();
2584         mount_info.mntfh = nfs_alloc_fhandle();
2585         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2586                 goto out;
2587
2588         /* Validate the mount data */
2589         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2590         if (error == NFS_TEXT_DATA)
2591                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2592         if (error < 0) {
2593                 mntroot = ERR_PTR(error);
2594                 goto out;
2595         }
2596
2597         nfs_mod = get_nfs_version(mount_info.parsed->version);
2598         if (IS_ERR(nfs_mod)) {
2599                 mntroot = ERR_CAST(nfs_mod);
2600                 goto out;
2601         }
2602
2603         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2604
2605         put_nfs_version(nfs_mod);
2606 out:
2607         nfs_free_parsed_mount_data(mount_info.parsed);
2608         nfs_free_fhandle(mount_info.mntfh);
2609         return mntroot;
2610 }
2611 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2612
2613 /*
2614  * Ensure that we unregister the bdi before kill_anon_super
2615  * releases the device name
2616  */
2617 void nfs_put_super(struct super_block *s)
2618 {
2619         struct nfs_server *server = NFS_SB(s);
2620
2621         bdi_unregister(&server->backing_dev_info);
2622 }
2623 EXPORT_SYMBOL_GPL(nfs_put_super);
2624
2625 /*
2626  * Destroy an NFS2/3 superblock
2627  */
2628 void nfs_kill_super(struct super_block *s)
2629 {
2630         struct nfs_server *server = NFS_SB(s);
2631
2632         kill_anon_super(s);
2633         nfs_fscache_release_super_cookie(s);
2634         nfs_free_server(server);
2635 }
2636 EXPORT_SYMBOL_GPL(nfs_kill_super);
2637
2638 /*
2639  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2640  */
2641 static struct dentry *
2642 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2643                 const char *dev_name, void *raw_data)
2644 {
2645         struct nfs_clone_mount *data = raw_data;
2646         struct nfs_mount_info mount_info = {
2647                 .fill_super = nfs_clone_super,
2648                 .set_security = nfs_clone_sb_security,
2649                 .cloned = data,
2650         };
2651         struct nfs_server *server;
2652         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2653         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2654
2655         dprintk("--> nfs_xdev_mount()\n");
2656
2657         mount_info.mntfh = mount_info.cloned->fh;
2658
2659         /* create a new volume representation */
2660         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2661
2662         if (IS_ERR(server))
2663                 mntroot = ERR_CAST(server);
2664         else
2665                 mntroot = nfs_fs_mount_common(server, flags,
2666                                 dev_name, &mount_info, nfs_mod);
2667
2668         dprintk("<-- nfs_xdev_mount() = %ld\n",
2669                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2670         return mntroot;
2671 }
2672
2673 #if IS_ENABLED(CONFIG_NFS_V4)
2674
2675 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2676 {
2677         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2678                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2679 }
2680
2681 /*
2682  * Validate NFSv4 mount options
2683  */
2684 static int nfs4_validate_mount_data(void *options,
2685                                     struct nfs_parsed_mount_data *args,
2686                                     const char *dev_name)
2687 {
2688         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2689         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2690         char *c;
2691
2692         if (data == NULL)
2693                 goto out_no_data;
2694
2695         args->version = 4;
2696
2697         switch (data->version) {
2698         case 1:
2699                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2700                         goto out_no_address;
2701                 if (data->host_addrlen == 0)
2702                         goto out_no_address;
2703                 args->nfs_server.addrlen = data->host_addrlen;
2704                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2705                         return -EFAULT;
2706                 if (!nfs_verify_server_address(sap))
2707                         goto out_no_address;
2708                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2709
2710                 if (data->auth_flavourlen) {
2711                         rpc_authflavor_t pseudoflavor;
2712                         if (data->auth_flavourlen > 1)
2713                                 goto out_inval_auth;
2714                         if (copy_from_user(&pseudoflavor,
2715                                            data->auth_flavours,
2716                                            sizeof(pseudoflavor)))
2717                                 return -EFAULT;
2718                         args->selected_flavor = pseudoflavor;
2719                 } else
2720                         args->selected_flavor = RPC_AUTH_UNIX;
2721
2722                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2723                 if (IS_ERR(c))
2724                         return PTR_ERR(c);
2725                 args->nfs_server.hostname = c;
2726
2727                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2728                 if (IS_ERR(c))
2729                         return PTR_ERR(c);
2730                 args->nfs_server.export_path = c;
2731                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2732
2733                 c = strndup_user(data->client_addr.data, 16);
2734                 if (IS_ERR(c))
2735                         return PTR_ERR(c);
2736                 args->client_address = c;
2737
2738                 /*
2739                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2740                  * can deal with.
2741                  */
2742
2743                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2744                 args->rsize     = data->rsize;
2745                 args->wsize     = data->wsize;
2746                 args->timeo     = data->timeo;
2747                 args->retrans   = data->retrans;
2748                 args->acregmin  = data->acregmin;
2749                 args->acregmax  = data->acregmax;
2750                 args->acdirmin  = data->acdirmin;
2751                 args->acdirmax  = data->acdirmax;
2752                 args->nfs_server.protocol = data->proto;
2753                 nfs_validate_transport_protocol(args);
2754                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2755                         goto out_invalid_transport_udp;
2756
2757                 break;
2758         default:
2759                 return NFS_TEXT_DATA;
2760         }
2761
2762         return 0;
2763
2764 out_no_data:
2765         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2766         return -EINVAL;
2767
2768 out_inval_auth:
2769         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2770                  data->auth_flavourlen);
2771         return -EINVAL;
2772
2773 out_no_address:
2774         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2775         return -EINVAL;
2776
2777 out_invalid_transport_udp:
2778         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2779         return -EINVAL;
2780 }
2781
2782 /*
2783  * NFS v4 module parameters need to stay in the
2784  * NFS client for backwards compatibility
2785  */
2786 unsigned int nfs_callback_set_tcpport;
2787 unsigned short nfs_callback_tcpport;
2788 /* Default cache timeout is 10 minutes */
2789 unsigned int nfs_idmap_cache_timeout = 600;
2790 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2791 bool nfs4_disable_idmapping = true;
2792 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2793 unsigned short send_implementation_id = 1;
2794 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2795 bool recover_lost_locks = false;
2796
2797 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2798 EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2799 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2800 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2801 EXPORT_SYMBOL_GPL(max_session_slots);
2802 EXPORT_SYMBOL_GPL(send_implementation_id);
2803 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2804 EXPORT_SYMBOL_GPL(recover_lost_locks);
2805
2806 #define NFS_CALLBACK_MAXPORTNR (65535U)
2807
2808 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2809 {
2810         unsigned long num;
2811         int ret;
2812
2813         if (!val)
2814                 return -EINVAL;
2815         ret = kstrtoul(val, 0, &num);
2816         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2817                 return -EINVAL;
2818         *((unsigned int *)kp->arg) = num;
2819         return 0;
2820 }
2821 static struct kernel_param_ops param_ops_portnr = {
2822         .set = param_set_portnr,
2823         .get = param_get_uint,
2824 };
2825 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2826
2827 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2828 module_param(nfs_idmap_cache_timeout, int, 0644);
2829 module_param(nfs4_disable_idmapping, bool, 0644);
2830 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2831                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2832 MODULE_PARM_DESC(nfs4_disable_idmapping,
2833                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2834 module_param(max_session_slots, ushort, 0644);
2835 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2836                 "requests the client will negotiate");
2837 module_param(send_implementation_id, ushort, 0644);
2838 MODULE_PARM_DESC(send_implementation_id,
2839                 "Send implementation ID with NFSv4.1 exchange_id");
2840 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2841
2842 module_param(recover_lost_locks, bool, 0644);
2843 MODULE_PARM_DESC(recover_lost_locks,
2844                  "If the server reports that a lock might be lost, "
2845                  "try to recover it risking data corruption.");
2846
2847
2848 #endif /* CONFIG_NFS_V4 */