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         .statfs         = nfs_statfs,
 315         .evict_inode    = nfs_evict_inode,
 316         .umount_begin   = nfs_umount_begin,
 317         .show_options   = nfs_show_options,
 318         .show_devname   = nfs_show_devname,
 319         .show_path      = nfs_show_path,
 320         .show_stats     = nfs_show_stats,
 321         .remount_fs     = nfs_remount,
 322 };
 323 EXPORT_SYMBOL_GPL(nfs_sops);
 324
 325 #if IS_ENABLED(CONFIG_NFS_V4)
 326 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 327 static int nfs4_validate_mount_data(void *options,
 328         struct nfs_parsed_mount_data *args, const char *dev_name);
 329
 330 struct file_system_type nfs4_fs_type = {
 331         .owner          = THIS_MODULE,
 332         .name           = "nfs4",
 333         .mount          = nfs_fs_mount,
 334         .kill_sb        = nfs_kill_super,
 335         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 336 };
 337 MODULE_ALIAS_FS("nfs4");
 338 MODULE_ALIAS("nfs4");
 339 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 340
 341 static int __init register_nfs4_fs(void)
 342 {
 343         return register_filesystem(&nfs4_fs_type);
 344 }
 345
 346 static void unregister_nfs4_fs(void)
 347 {
 348         unregister_filesystem(&nfs4_fs_type);
 349 }
 350 #else
 351 static int __init register_nfs4_fs(void)
 352 {
 353         return 0;
 354 }
 355
 356 static void unregister_nfs4_fs(void)
 357 {
 358 }
 359 #endif
 360
 361 static struct shrinker acl_shrinker = {
 362         .count_objects  = nfs_access_cache_count,
 363         .scan_objects   = nfs_access_cache_scan,
 364         .seeks          = DEFAULT_SEEKS,
 365 };
 366
 367 /*
 368  * Register the NFS filesystems
 369  */
 370 int __init register_nfs_fs(void)
 371 {
 372         int ret;
 373
 374         ret = register_filesystem(&nfs_fs_type);
 375         if (ret < 0)
 376                 goto error_0;
 377
 378         ret = register_nfs4_fs();
 379         if (ret < 0)
 380                 goto error_1;
 381
 382         ret = nfs_register_sysctl();
 383         if (ret < 0)
 384                 goto error_2;
 385         register_shrinker(&acl_shrinker);
 386         return 0;
 387
 388 error_2:
 389         unregister_nfs4_fs();
 390 error_1:
 391         unregister_filesystem(&nfs_fs_type);
 392 error_0:
 393         return ret;
 394 }
 395
 396 /*
 397  * Unregister the NFS filesystems
 398  */
 399 void __exit unregister_nfs_fs(void)
 400 {
 401         unregister_shrinker(&acl_shrinker);
 402         nfs_unregister_sysctl();
 403         unregister_nfs4_fs();
 404         unregister_filesystem(&nfs_fs_type);
 405 }
 406
 407 void nfs_sb_active(struct super_block *sb)
 408 {
 409         struct nfs_server *server = NFS_SB(sb);
 410
 411         if (atomic_inc_return(&server->active) == 1)
 412                 atomic_inc(&sb->s_active);
 413 }
 414 EXPORT_SYMBOL_GPL(nfs_sb_active);
 415
 416 void nfs_sb_deactive(struct super_block *sb)
 417 {
 418         struct nfs_server *server = NFS_SB(sb);
 419
 420         if (atomic_dec_and_test(&server->active))
 421                 deactivate_super(sb);
 422 }
 423 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 424
 425 /*
 426  * Deliver file system statistics to userspace
 427  */
 428 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 429 {
 430         struct nfs_server *server = NFS_SB(dentry->d_sb);
 431         unsigned char blockbits;
 432         unsigned long blockres;
 433         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 434         struct nfs_fsstat res;
 435         int error = -ENOMEM;
 436
 437         res.fattr = nfs_alloc_fattr();
 438         if (res.fattr == NULL)
 439                 goto out_err;
 440
 441         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 442         if (unlikely(error == -ESTALE)) {
 443                 struct dentry *pd_dentry;
 444
 445                 pd_dentry = dget_parent(dentry);
 446                 if (pd_dentry != NULL) {
 447                         nfs_zap_caches(pd_dentry->d_inode);
 448                         dput(pd_dentry);
 449                 }
 450         }
 451         nfs_free_fattr(res.fattr);
 452         if (error < 0)
 453                 goto out_err;
 454
 455         buf->f_type = NFS_SUPER_MAGIC;
 456
 457         /*
 458          * Current versions of glibc do not correctly handle the
 459          * case where f_frsize != f_bsize.  Eventually we want to
 460          * report the value of wtmult in this field.
 461          */
 462         buf->f_frsize = dentry->d_sb->s_blocksize;
 463
 464         /*
 465          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 466          * are reported in units of f_frsize.  Linux hasn't had
 467          * an f_frsize field in its statfs struct until recently,
 468          * thus historically Linux's sys_statfs reports these
 469          * fields in units of f_bsize.
 470          */
 471         buf->f_bsize = dentry->d_sb->s_blocksize;
 472         blockbits = dentry->d_sb->s_blocksize_bits;
 473         blockres = (1 << blockbits) - 1;
 474         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 475         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 476         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 477
 478         buf->f_files = res.tfiles;
 479         buf->f_ffree = res.afiles;
 480
 481         buf->f_namelen = server->namelen;
 482
 483         return 0;
 484
 485  out_err:
 486         dprintk("%s: statfs error = %d\n", __func__, -error);
 487         return error;
 488 }
 489 EXPORT_SYMBOL_GPL(nfs_statfs);
 490
 491 /*
 492  * Map the security flavour number to a name
 493  */
 494 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 495 {
 496         static const struct {
 497                 rpc_authflavor_t flavour;
 498                 const char *str;
 499         } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
 500                 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
 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  * Add 'flavor' to 'auth_info' if not already present.
1023  * Returns true if 'flavor' ends up in the list, false otherwise
1024  */
1025 static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
1026                               rpc_authflavor_t flavor)
1027 {
1028         unsigned int i;
1029         unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
1030
1031         /* make sure this flavor isn't already in the list */
1032         for (i = 0; i < auth_info->flavor_len; i++) {
1033                 if (flavor == auth_info->flavors[i])
1034                         return true;
1035         }
1036
1037         if (auth_info->flavor_len + 1 >= max_flavor_len) {
1038                 dfprintk(MOUNT, "NFS: too many sec= flavors\n");
1039                 return false;
1040         }
1041
1042         auth_info->flavors[auth_info->flavor_len++] = flavor;
1043         return true;
1044 }
1045
1046 /*
1047  * Return true if 'match' is in auth_info or auth_info is empty.
1048  * Return false otherwise.
1049  */
1050 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
1051                          rpc_authflavor_t match)
1052 {
1053         int i;
1054
1055         if (!auth_info->flavor_len)
1056                 return true;
1057
1058         for (i = 0; i < auth_info->flavor_len; i++) {
1059                 if (auth_info->flavors[i] == match)
1060                         return true;
1061         }
1062         return false;
1063 }
1064 EXPORT_SYMBOL_GPL(nfs_auth_info_match);
1065
1066 /*
1067  * Parse the value of the 'sec=' option.
1068  */
1069 static int nfs_parse_security_flavors(char *value,
1070                                       struct nfs_parsed_mount_data *mnt)
1071 {
1072         substring_t args[MAX_OPT_ARGS];
1073         rpc_authflavor_t pseudoflavor;
1074         char *p;
1075
1076         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1077
1078         while ((p = strsep(&value, ":")) != NULL) {
1079                 switch (match_token(p, nfs_secflavor_tokens, args)) {
1080                 case Opt_sec_none:
1081                         pseudoflavor = RPC_AUTH_NULL;
1082                         break;
1083                 case Opt_sec_sys:
1084                         pseudoflavor = RPC_AUTH_UNIX;
1085                         break;
1086                 case Opt_sec_krb5:
1087                         pseudoflavor = RPC_AUTH_GSS_KRB5;
1088                         break;
1089                 case Opt_sec_krb5i:
1090                         pseudoflavor = RPC_AUTH_GSS_KRB5I;
1091                         break;
1092                 case Opt_sec_krb5p:
1093                         pseudoflavor = RPC_AUTH_GSS_KRB5P;
1094                         break;
1095                 case Opt_sec_lkey:
1096                         pseudoflavor = RPC_AUTH_GSS_LKEY;
1097                         break;
1098                 case Opt_sec_lkeyi:
1099                         pseudoflavor = RPC_AUTH_GSS_LKEYI;
1100                         break;
1101                 case Opt_sec_lkeyp:
1102                         pseudoflavor = RPC_AUTH_GSS_LKEYP;
1103                         break;
1104                 case Opt_sec_spkm:
1105                         pseudoflavor = RPC_AUTH_GSS_SPKM;
1106                         break;
1107                 case Opt_sec_spkmi:
1108                         pseudoflavor = RPC_AUTH_GSS_SPKMI;
1109                         break;
1110                 case Opt_sec_spkmp:
1111                         pseudoflavor = RPC_AUTH_GSS_SPKMP;
1112                         break;
1113                 default:
1114                         dfprintk(MOUNT,
1115                                  "NFS: sec= option '%s' not recognized\n", p);
1116                         return 0;
1117                 }
1118
1119                 if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
1120                         return 0;
1121         }
1122
1123         return 1;
1124 }
1125
1126 static int nfs_parse_version_string(char *string,
1127                 struct nfs_parsed_mount_data *mnt,
1128                 substring_t *args)
1129 {
1130         mnt->flags &= ~NFS_MOUNT_VER3;
1131         switch (match_token(string, nfs_vers_tokens, args)) {
1132         case Opt_vers_2:
1133                 mnt->version = 2;
1134                 break;
1135         case Opt_vers_3:
1136                 mnt->flags |= NFS_MOUNT_VER3;
1137                 mnt->version = 3;
1138                 break;
1139         case Opt_vers_4:
1140                 /* Backward compatibility option. In future,
1141                  * the mount program should always supply
1142                  * a NFSv4 minor version number.
1143                  */
1144                 mnt->version = 4;
1145                 break;
1146         case Opt_vers_4_0:
1147                 mnt->version = 4;
1148                 mnt->minorversion = 0;
1149                 break;
1150         case Opt_vers_4_1:
1151                 mnt->version = 4;
1152                 mnt->minorversion = 1;
1153                 break;
1154         case Opt_vers_4_2:
1155                 mnt->version = 4;
1156                 mnt->minorversion = 2;
1157                 break;
1158         default:
1159                 return 0;
1160         }
1161         return 1;
1162 }
1163
1164 static int nfs_get_option_str(substring_t args[], char **option)
1165 {
1166         kfree(*option);
1167         *option = match_strdup(args);
1168         return !*option;
1169 }
1170
1171 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1172 {
1173         int rc;
1174         char *string;
1175
1176         string = match_strdup(args);
1177         if (string == NULL)
1178                 return -ENOMEM;
1179         rc = kstrtoul(string, 10, option);
1180         kfree(string);
1181
1182         return rc;
1183 }
1184
1185 /*
1186  * Error-check and convert a string of mount options from user space into
1187  * a data structure.  The whole mount string is processed; bad options are
1188  * skipped as they are encountered.  If there were no errors, return 1;
1189  * otherwise return 0 (zero).
1190  */
1191 static int nfs_parse_mount_options(char *raw,
1192                                    struct nfs_parsed_mount_data *mnt)
1193 {
1194         char *p, *string, *secdata;
1195         int rc, sloppy = 0, invalid_option = 0;
1196         unsigned short protofamily = AF_UNSPEC;
1197         unsigned short mountfamily = AF_UNSPEC;
1198
1199         if (!raw) {
1200                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1201                 return 1;
1202         }
1203         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1204
1205         secdata = alloc_secdata();
1206         if (!secdata)
1207                 goto out_nomem;
1208
1209         rc = security_sb_copy_data(raw, secdata);
1210         if (rc)
1211                 goto out_security_failure;
1212
1213         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1214         if (rc)
1215                 goto out_security_failure;
1216
1217         free_secdata(secdata);
1218
1219         while ((p = strsep(&raw, ",")) != NULL) {
1220                 substring_t args[MAX_OPT_ARGS];
1221                 unsigned long option;
1222                 int token;
1223
1224                 if (!*p)
1225                         continue;
1226
1227                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1228
1229                 token = match_token(p, nfs_mount_option_tokens, args);
1230                 switch (token) {
1231
1232                 /*
1233                  * boolean options:  foo/nofoo
1234                  */
1235                 case Opt_soft:
1236                         mnt->flags |= NFS_MOUNT_SOFT;
1237                         break;
1238                 case Opt_hard:
1239                         mnt->flags &= ~NFS_MOUNT_SOFT;
1240                         break;
1241                 case Opt_posix:
1242                         mnt->flags |= NFS_MOUNT_POSIX;
1243                         break;
1244                 case Opt_noposix:
1245                         mnt->flags &= ~NFS_MOUNT_POSIX;
1246                         break;
1247                 case Opt_cto:
1248                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1249                         break;
1250                 case Opt_nocto:
1251                         mnt->flags |= NFS_MOUNT_NOCTO;
1252                         break;
1253                 case Opt_ac:
1254                         mnt->flags &= ~NFS_MOUNT_NOAC;
1255                         break;
1256                 case Opt_noac:
1257                         mnt->flags |= NFS_MOUNT_NOAC;
1258                         break;
1259                 case Opt_lock:
1260                         mnt->flags &= ~NFS_MOUNT_NONLM;
1261                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1262                                         NFS_MOUNT_LOCAL_FCNTL);
1263                         break;
1264                 case Opt_nolock:
1265                         mnt->flags |= NFS_MOUNT_NONLM;
1266                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1267                                        NFS_MOUNT_LOCAL_FCNTL);
1268                         break;
1269                 case Opt_udp:
1270                         mnt->flags &= ~NFS_MOUNT_TCP;
1271                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1272                         break;
1273                 case Opt_tcp:
1274                         mnt->flags |= NFS_MOUNT_TCP;
1275                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1276                         break;
1277                 case Opt_rdma:
1278                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1279                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1280                         xprt_load_transport(p);
1281                         break;
1282                 case Opt_acl:
1283                         mnt->flags &= ~NFS_MOUNT_NOACL;
1284                         break;
1285                 case Opt_noacl:
1286                         mnt->flags |= NFS_MOUNT_NOACL;
1287                         break;
1288                 case Opt_rdirplus:
1289                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1290                         break;
1291                 case Opt_nordirplus:
1292                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1293                         break;
1294                 case Opt_sharecache:
1295                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1296                         break;
1297                 case Opt_nosharecache:
1298                         mnt->flags |= NFS_MOUNT_UNSHARED;
1299                         break;
1300                 case Opt_resvport:
1301                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1302                         break;
1303                 case Opt_noresvport:
1304                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1305                         break;
1306                 case Opt_fscache:
1307                         mnt->options |= NFS_OPTION_FSCACHE;
1308                         kfree(mnt->fscache_uniq);
1309                         mnt->fscache_uniq = NULL;
1310                         break;
1311                 case Opt_nofscache:
1312                         mnt->options &= ~NFS_OPTION_FSCACHE;
1313                         kfree(mnt->fscache_uniq);
1314                         mnt->fscache_uniq = NULL;
1315                         break;
1316                 case Opt_migration:
1317                         mnt->options |= NFS_OPTION_MIGRATION;
1318                         break;
1319                 case Opt_nomigration:
1320                         mnt->options &= NFS_OPTION_MIGRATION;
1321                         break;
1322
1323                 /*
1324                  * options that take numeric values
1325                  */
1326                 case Opt_port:
1327                         if (nfs_get_option_ul(args, &option) ||
1328                             option > USHRT_MAX)
1329                                 goto out_invalid_value;
1330                         mnt->nfs_server.port = option;
1331                         break;
1332                 case Opt_rsize:
1333                         if (nfs_get_option_ul(args, &option))
1334                                 goto out_invalid_value;
1335                         mnt->rsize = option;
1336                         break;
1337                 case Opt_wsize:
1338                         if (nfs_get_option_ul(args, &option))
1339                                 goto out_invalid_value;
1340                         mnt->wsize = option;
1341                         break;
1342                 case Opt_bsize:
1343                         if (nfs_get_option_ul(args, &option))
1344                                 goto out_invalid_value;
1345                         mnt->bsize = option;
1346                         break;
1347                 case Opt_timeo:
1348                         if (nfs_get_option_ul(args, &option) || option == 0)
1349                                 goto out_invalid_value;
1350                         mnt->timeo = option;
1351                         break;
1352                 case Opt_retrans:
1353                         if (nfs_get_option_ul(args, &option) || option == 0)
1354                                 goto out_invalid_value;
1355                         mnt->retrans = option;
1356                         break;
1357                 case Opt_acregmin:
1358                         if (nfs_get_option_ul(args, &option))
1359                                 goto out_invalid_value;
1360                         mnt->acregmin = option;
1361                         break;
1362                 case Opt_acregmax:
1363                         if (nfs_get_option_ul(args, &option))
1364                                 goto out_invalid_value;
1365                         mnt->acregmax = option;
1366                         break;
1367                 case Opt_acdirmin:
1368                         if (nfs_get_option_ul(args, &option))
1369                                 goto out_invalid_value;
1370                         mnt->acdirmin = option;
1371                         break;
1372                 case Opt_acdirmax:
1373                         if (nfs_get_option_ul(args, &option))
1374                                 goto out_invalid_value;
1375                         mnt->acdirmax = option;
1376                         break;
1377                 case Opt_actimeo:
1378                         if (nfs_get_option_ul(args, &option))
1379                                 goto out_invalid_value;
1380                         mnt->acregmin = mnt->acregmax =
1381                         mnt->acdirmin = mnt->acdirmax = option;
1382                         break;
1383                 case Opt_namelen:
1384                         if (nfs_get_option_ul(args, &option))
1385                                 goto out_invalid_value;
1386                         mnt->namlen = option;
1387                         break;
1388                 case Opt_mountport:
1389                         if (nfs_get_option_ul(args, &option) ||
1390                             option > USHRT_MAX)
1391                                 goto out_invalid_value;
1392                         mnt->mount_server.port = option;
1393                         break;
1394                 case Opt_mountvers:
1395                         if (nfs_get_option_ul(args, &option) ||
1396                             option < NFS_MNT_VERSION ||
1397                             option > NFS_MNT3_VERSION)
1398                                 goto out_invalid_value;
1399                         mnt->mount_server.version = option;
1400                         break;
1401                 case Opt_minorversion:
1402                         if (nfs_get_option_ul(args, &option))
1403                                 goto out_invalid_value;
1404                         if (option > NFS4_MAX_MINOR_VERSION)
1405                                 goto out_invalid_value;
1406                         mnt->minorversion = option;
1407                         break;
1408
1409                 /*
1410                  * options that take text values
1411                  */
1412                 case Opt_nfsvers:
1413                         string = match_strdup(args);
1414                         if (string == NULL)
1415                                 goto out_nomem;
1416                         rc = nfs_parse_version_string(string, mnt, args);
1417                         kfree(string);
1418                         if (!rc)
1419                                 goto out_invalid_value;
1420                         break;
1421                 case Opt_sec:
1422                         string = match_strdup(args);
1423                         if (string == NULL)
1424                                 goto out_nomem;
1425                         rc = nfs_parse_security_flavors(string, mnt);
1426                         kfree(string);
1427                         if (!rc) {
1428                                 dfprintk(MOUNT, "NFS:   unrecognized "
1429                                                 "security flavor\n");
1430                                 return 0;
1431                         }
1432                         break;
1433                 case Opt_proto:
1434                         string = match_strdup(args);
1435                         if (string == NULL)
1436                                 goto out_nomem;
1437                         token = match_token(string,
1438                                             nfs_xprt_protocol_tokens, args);
1439
1440                         protofamily = AF_INET;
1441                         switch (token) {
1442                         case Opt_xprt_udp6:
1443                                 protofamily = AF_INET6;
1444                         case Opt_xprt_udp:
1445                                 mnt->flags &= ~NFS_MOUNT_TCP;
1446                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1447                                 break;
1448                         case Opt_xprt_tcp6:
1449                                 protofamily = AF_INET6;
1450                         case Opt_xprt_tcp:
1451                                 mnt->flags |= NFS_MOUNT_TCP;
1452                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1453                                 break;
1454                         case Opt_xprt_rdma:
1455                                 /* vector side protocols to TCP */
1456                                 mnt->flags |= NFS_MOUNT_TCP;
1457                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1458                                 xprt_load_transport(string);
1459                                 break;
1460                         default:
1461                                 dfprintk(MOUNT, "NFS:   unrecognized "
1462                                                 "transport protocol\n");
1463                                 kfree(string);
1464                                 return 0;
1465                         }
1466                         kfree(string);
1467                         break;
1468                 case Opt_mountproto:
1469                         string = match_strdup(args);
1470                         if (string == NULL)
1471                                 goto out_nomem;
1472                         token = match_token(string,
1473                                             nfs_xprt_protocol_tokens, args);
1474                         kfree(string);
1475
1476                         mountfamily = AF_INET;
1477                         switch (token) {
1478                         case Opt_xprt_udp6:
1479                                 mountfamily = AF_INET6;
1480                         case Opt_xprt_udp:
1481                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1482                                 break;
1483                         case Opt_xprt_tcp6:
1484                                 mountfamily = AF_INET6;
1485                         case Opt_xprt_tcp:
1486                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1487                                 break;
1488                         case Opt_xprt_rdma: /* not used for side protocols */
1489                         default:
1490                                 dfprintk(MOUNT, "NFS:   unrecognized "
1491                                                 "transport protocol\n");
1492                                 return 0;
1493                         }
1494                         break;
1495                 case Opt_addr:
1496                         string = match_strdup(args);
1497                         if (string == NULL)
1498                                 goto out_nomem;
1499                         mnt->nfs_server.addrlen =
1500                                 rpc_pton(mnt->net, string, strlen(string),
1501                                         (struct sockaddr *)
1502                                         &mnt->nfs_server.address,
1503                                         sizeof(mnt->nfs_server.address));
1504                         kfree(string);
1505                         if (mnt->nfs_server.addrlen == 0)
1506                                 goto out_invalid_address;
1507                         break;
1508                 case Opt_clientaddr:
1509                         if (nfs_get_option_str(args, &mnt->client_address))
1510                                 goto out_nomem;
1511                         break;
1512                 case Opt_mounthost:
1513                         if (nfs_get_option_str(args,
1514                                                &mnt->mount_server.hostname))
1515                                 goto out_nomem;
1516                         break;
1517                 case Opt_mountaddr:
1518                         string = match_strdup(args);
1519                         if (string == NULL)
1520                                 goto out_nomem;
1521                         mnt->mount_server.addrlen =
1522                                 rpc_pton(mnt->net, string, strlen(string),
1523                                         (struct sockaddr *)
1524                                         &mnt->mount_server.address,
1525                                         sizeof(mnt->mount_server.address));
1526                         kfree(string);
1527                         if (mnt->mount_server.addrlen == 0)
1528                                 goto out_invalid_address;
1529                         break;
1530                 case Opt_lookupcache:
1531                         string = match_strdup(args);
1532                         if (string == NULL)
1533                                 goto out_nomem;
1534                         token = match_token(string,
1535                                         nfs_lookupcache_tokens, args);
1536                         kfree(string);
1537                         switch (token) {
1538                                 case Opt_lookupcache_all:
1539                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1540                                         break;
1541                                 case Opt_lookupcache_positive:
1542                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1543                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1544                                         break;
1545                                 case Opt_lookupcache_none:
1546                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1547                                         break;
1548                                 default:
1549                                         dfprintk(MOUNT, "NFS:   invalid "
1550                                                         "lookupcache argument\n");
1551                                         return 0;
1552                         };
1553                         break;
1554                 case Opt_fscache_uniq:
1555                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1556                                 goto out_nomem;
1557                         mnt->options |= NFS_OPTION_FSCACHE;
1558                         break;
1559                 case Opt_local_lock:
1560                         string = match_strdup(args);
1561                         if (string == NULL)
1562                                 goto out_nomem;
1563                         token = match_token(string, nfs_local_lock_tokens,
1564                                         args);
1565                         kfree(string);
1566                         switch (token) {
1567                         case Opt_local_lock_all:
1568                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1569                                                NFS_MOUNT_LOCAL_FCNTL);
1570                                 break;
1571                         case Opt_local_lock_flock:
1572                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1573                                 break;
1574                         case Opt_local_lock_posix:
1575                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1576                                 break;
1577                         case Opt_local_lock_none:
1578                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1579                                                 NFS_MOUNT_LOCAL_FCNTL);
1580                                 break;
1581                         default:
1582                                 dfprintk(MOUNT, "NFS:   invalid "
1583                                                 "local_lock argument\n");
1584                                 return 0;
1585                         };
1586                         break;
1587
1588                 /*
1589                  * Special options
1590                  */
1591                 case Opt_sloppy:
1592                         sloppy = 1;
1593                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1594                         break;
1595                 case Opt_userspace:
1596                 case Opt_deprecated:
1597                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1598                                         "'%s'\n", p);
1599                         break;
1600
1601                 default:
1602                         invalid_option = 1;
1603                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1604                                         "'%s'\n", p);
1605                 }
1606         }
1607
1608         if (!sloppy && invalid_option)
1609                 return 0;
1610
1611         if (mnt->minorversion && mnt->version != 4)
1612                 goto out_minorversion_mismatch;
1613
1614         if (mnt->options & NFS_OPTION_MIGRATION &&
1615             (mnt->version != 4 || mnt->minorversion != 0))
1616                 goto out_migration_misuse;
1617
1618         /*
1619          * verify that any proto=/mountproto= options match the address
1620          * families in the addr=/mountaddr= options.
1621          */
1622         if (protofamily != AF_UNSPEC &&
1623             protofamily != mnt->nfs_server.address.ss_family)
1624                 goto out_proto_mismatch;
1625
1626         if (mountfamily != AF_UNSPEC) {
1627                 if (mnt->mount_server.addrlen) {
1628                         if (mountfamily != mnt->mount_server.address.ss_family)
1629                                 goto out_mountproto_mismatch;
1630                 } else {
1631                         if (mountfamily != mnt->nfs_server.address.ss_family)
1632                                 goto out_mountproto_mismatch;
1633                 }
1634         }
1635
1636         return 1;
1637
1638 out_mountproto_mismatch:
1639         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1640                          "option\n");
1641         return 0;
1642 out_proto_mismatch:
1643         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1644         return 0;
1645 out_invalid_address:
1646         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1647         return 0;
1648 out_invalid_value:
1649         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1650         return 0;
1651 out_minorversion_mismatch:
1652         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1653                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1654         return 0;
1655 out_migration_misuse:
1656         printk(KERN_INFO
1657                 "NFS: 'migration' not supported for this NFS version\n");
1658         return 0;
1659 out_nomem:
1660         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1661         return 0;
1662 out_security_failure:
1663         free_secdata(secdata);
1664         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1665         return 0;
1666 }
1667
1668 /*
1669  * Ensure that a specified authtype in args->auth_info is supported by
1670  * the server. Returns 0 and sets args->selected_flavor if it's ok, and
1671  * -EACCES if not.
1672  */
1673 static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
1674                         rpc_authflavor_t *server_authlist, unsigned int count)
1675 {
1676         rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
1677         unsigned int i;
1678
1679         /*
1680          * If the sec= mount option is used, the specified flavor or AUTH_NULL
1681          * must be in the list returned by the server.
1682          *
1683          * AUTH_NULL has a special meaning when it's in the server list - it
1684          * means that the server will ignore the rpc creds, so any flavor
1685          * can be used.
1686          */
1687         for (i = 0; i < count; i++) {
1688                 flavor = server_authlist[i];
1689
1690                 if (nfs_auth_info_match(&args->auth_info, flavor) ||
1691                     flavor == RPC_AUTH_NULL)
1692                         goto out;
1693         }
1694
1695         dfprintk(MOUNT,
1696                  "NFS: specified auth flavors not supported by server\n");
1697         return -EACCES;
1698
1699 out:
1700         args->selected_flavor = flavor;
1701         dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
1702         return 0;
1703 }
1704
1705 /*
1706  * Use the remote server's MOUNT service to request the NFS file handle
1707  * corresponding to the provided path.
1708  */
1709 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1710                              struct nfs_fh *root_fh,
1711                              rpc_authflavor_t *server_authlist,
1712                              unsigned int *server_authlist_len)
1713 {
1714         struct nfs_mount_request request = {
1715                 .sap            = (struct sockaddr *)
1716                                                 &args->mount_server.address,
1717                 .dirpath        = args->nfs_server.export_path,
1718                 .protocol       = args->mount_server.protocol,
1719                 .fh             = root_fh,
1720                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1721                 .auth_flav_len  = server_authlist_len,
1722                 .auth_flavs     = server_authlist,
1723                 .net            = args->net,
1724         };
1725         int status;
1726
1727         if (args->mount_server.version == 0) {
1728                 switch (args->version) {
1729                         default:
1730                                 args->mount_server.version = NFS_MNT3_VERSION;
1731                                 break;
1732                         case 2:
1733                                 args->mount_server.version = NFS_MNT_VERSION;
1734                 }
1735         }
1736         request.version = args->mount_server.version;
1737
1738         if (args->mount_server.hostname)
1739                 request.hostname = args->mount_server.hostname;
1740         else
1741                 request.hostname = args->nfs_server.hostname;
1742
1743         /*
1744          * Construct the mount server's address.
1745          */
1746         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1747                 memcpy(request.sap, &args->nfs_server.address,
1748                        args->nfs_server.addrlen);
1749                 args->mount_server.addrlen = args->nfs_server.addrlen;
1750         }
1751         request.salen = args->mount_server.addrlen;
1752         nfs_set_port(request.sap, &args->mount_server.port, 0);
1753
1754         /*
1755          * Now ask the mount server to map our export path
1756          * to a file handle.
1757          */
1758         status = nfs_mount(&request);
1759         if (status != 0) {
1760                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1761                                 request.hostname, status);
1762                 return status;
1763         }
1764
1765         return 0;
1766 }
1767
1768 static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1769                                         struct nfs_subversion *nfs_mod)
1770 {
1771         int status;
1772         unsigned int i;
1773         bool tried_auth_unix = false;
1774         bool auth_null_in_list = false;
1775         struct nfs_server *server = ERR_PTR(-EACCES);
1776         struct nfs_parsed_mount_data *args = mount_info->parsed;
1777         rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1778         unsigned int authlist_len = ARRAY_SIZE(authlist);
1779
1780         status = nfs_request_mount(args, mount_info->mntfh, authlist,
1781                                         &authlist_len);
1782         if (status)
1783                 return ERR_PTR(status);
1784
1785         /*
1786          * Was a sec= authflavor specified in the options? First, verify
1787          * whether the server supports it, and then just try to use it if so.
1788          */
1789         if (args->auth_info.flavor_len > 0) {
1790                 status = nfs_verify_authflavors(args, authlist, authlist_len);
1791                 dfprintk(MOUNT, "NFS: using auth flavor %u\n",
1792                          args->selected_flavor);
1793                 if (status)
1794                         return ERR_PTR(status);
1795                 return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1796         }
1797
1798         /*
1799          * No sec= option was provided. RFC 2623, section 2.7 suggests we
1800          * SHOULD prefer the flavor listed first. However, some servers list
1801          * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1802          */
1803         for (i = 0; i < authlist_len; ++i) {
1804                 rpc_authflavor_t flavor;
1805                 struct rpcsec_gss_info info;
1806
1807                 flavor = authlist[i];
1808                 switch (flavor) {
1809                 case RPC_AUTH_UNIX:
1810                         tried_auth_unix = true;
1811                         break;
1812                 case RPC_AUTH_NULL:
1813                         auth_null_in_list = true;
1814                         continue;
1815                 default:
1816                         if (rpcauth_get_gssinfo(flavor, &info) != 0)
1817                                 continue;
1818                         /* Fallthrough */
1819                 }
1820                 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1821                 args->selected_flavor = flavor;
1822                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1823                 if (!IS_ERR(server))
1824                         return server;
1825         }
1826
1827         /*
1828          * Nothing we tried so far worked. At this point, give up if we've
1829          * already tried AUTH_UNIX or if the server's list doesn't contain
1830          * AUTH_NULL
1831          */
1832         if (tried_auth_unix || !auth_null_in_list)
1833                 return server;
1834
1835         /* Last chance! Try AUTH_UNIX */
1836         dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1837         args->selected_flavor = RPC_AUTH_UNIX;
1838         return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1839 }
1840
1841 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1842                              struct nfs_mount_info *mount_info,
1843                              struct nfs_subversion *nfs_mod)
1844 {
1845         struct nfs_server *server;
1846
1847         if (mount_info->parsed->need_mount)
1848                 server = nfs_try_mount_request(mount_info, nfs_mod);
1849         else
1850                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1851
1852         if (IS_ERR(server))
1853                 return ERR_CAST(server);
1854
1855         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1856 }
1857 EXPORT_SYMBOL_GPL(nfs_try_mount);
1858
1859 /*
1860  * Split "dev_name" into "hostname:export_path".
1861  *
1862  * The leftmost colon demarks the split between the server's hostname
1863  * and the export path.  If the hostname starts with a left square
1864  * bracket, then it may contain colons.
1865  *
1866  * Note: caller frees hostname and export path, even on error.
1867  */
1868 static int nfs_parse_devname(const char *dev_name,
1869                              char **hostname, size_t maxnamlen,
1870                              char **export_path, size_t maxpathlen)
1871 {
1872         size_t len;
1873         char *end;
1874
1875         /* Is the host name protected with square brakcets? */
1876         if (*dev_name == '[') {
1877                 end = strchr(++dev_name, ']');
1878                 if (end == NULL || end[1] != ':')
1879                         goto out_bad_devname;
1880
1881                 len = end - dev_name;
1882                 end++;
1883         } else {
1884                 char *comma;
1885
1886                 end = strchr(dev_name, ':');
1887                 if (end == NULL)
1888                         goto out_bad_devname;
1889                 len = end - dev_name;
1890
1891                 /* kill possible hostname list: not supported */
1892                 comma = strchr(dev_name, ',');
1893                 if (comma != NULL && comma < end)
1894                         *comma = 0;
1895         }
1896
1897         if (len > maxnamlen)
1898                 goto out_hostname;
1899
1900         /* N.B. caller will free nfs_server.hostname in all cases */
1901         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1902         if (*hostname == NULL)
1903                 goto out_nomem;
1904         len = strlen(++end);
1905         if (len > maxpathlen)
1906                 goto out_path;
1907         *export_path = kstrndup(end, len, GFP_KERNEL);
1908         if (!*export_path)
1909                 goto out_nomem;
1910
1911         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1912         return 0;
1913
1914 out_bad_devname:
1915         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1916         return -EINVAL;
1917
1918 out_nomem:
1919         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1920         return -ENOMEM;
1921
1922 out_hostname:
1923         dfprintk(MOUNT, "NFS: server hostname too long\n");
1924         return -ENAMETOOLONG;
1925
1926 out_path:
1927         dfprintk(MOUNT, "NFS: export pathname too long\n");
1928         return -ENAMETOOLONG;
1929 }
1930
1931 /*
1932  * Validate the NFS2/NFS3 mount data
1933  * - fills in the mount root filehandle
1934  *
1935  * For option strings, user space handles the following behaviors:
1936  *
1937  * + DNS: mapping server host name to IP address ("addr=" option)
1938  *
1939  * + failure mode: how to behave if a mount request can't be handled
1940  *   immediately ("fg/bg" option)
1941  *
1942  * + retry: how often to retry a mount request ("retry=" option)
1943  *
1944  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1945  *   mountproto=tcp after mountproto=udp, and so on
1946  */
1947 static int nfs23_validate_mount_data(void *options,
1948                                      struct nfs_parsed_mount_data *args,
1949                                      struct nfs_fh *mntfh,
1950                                      const char *dev_name)
1951 {
1952         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1953         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1954         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1955
1956         if (data == NULL)
1957                 goto out_no_data;
1958
1959         args->version = NFS_DEFAULT_VERSION;
1960         switch (data->version) {
1961         case 1:
1962                 data->namlen = 0;
1963         case 2:
1964                 data->bsize = 0;
1965         case 3:
1966                 if (data->flags & NFS_MOUNT_VER3)
1967                         goto out_no_v3;
1968                 data->root.size = NFS2_FHSIZE;
1969                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1970                 /* Turn off security negotiation */
1971                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
1972         case 4:
1973                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1974                         goto out_no_sec;
1975         case 5:
1976                 memset(data->context, 0, sizeof(data->context));
1977         case 6:
1978                 if (data->flags & NFS_MOUNT_VER3) {
1979                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1980                                 goto out_invalid_fh;
1981                         mntfh->size = data->root.size;
1982                         args->version = 3;
1983                 } else {
1984                         mntfh->size = NFS2_FHSIZE;
1985                         args->version = 2;
1986                 }
1987
1988
1989                 memcpy(mntfh->data, data->root.data, mntfh->size);
1990                 if (mntfh->size < sizeof(mntfh->data))
1991                         memset(mntfh->data + mntfh->size, 0,
1992                                sizeof(mntfh->data) - mntfh->size);
1993
1994                 /*
1995                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1996                  * can deal with.
1997                  */
1998                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1999                 args->flags             |= extra_flags;
2000                 args->rsize             = data->rsize;
2001                 args->wsize             = data->wsize;
2002                 args->timeo             = data->timeo;
2003                 args->retrans           = data->retrans;
2004                 args->acregmin          = data->acregmin;
2005                 args->acregmax          = data->acregmax;
2006                 args->acdirmin          = data->acdirmin;
2007                 args->acdirmax          = data->acdirmax;
2008                 args->need_mount        = false;
2009
2010                 memcpy(sap, &data->addr, sizeof(data->addr));
2011                 args->nfs_server.addrlen = sizeof(data->addr);
2012                 args->nfs_server.port = ntohs(data->addr.sin_port);
2013                 if (!nfs_verify_server_address(sap))
2014                         goto out_no_address;
2015
2016                 if (!(data->flags & NFS_MOUNT_TCP))
2017                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
2018                 /* N.B. caller will free nfs_server.hostname in all cases */
2019                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
2020                 args->namlen            = data->namlen;
2021                 args->bsize             = data->bsize;
2022
2023                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
2024                         args->selected_flavor = data->pseudoflavor;
2025                 else
2026                         args->selected_flavor = RPC_AUTH_UNIX;
2027                 if (!args->nfs_server.hostname)
2028                         goto out_nomem;
2029
2030                 if (!(data->flags & NFS_MOUNT_NONLM))
2031                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
2032                                          NFS_MOUNT_LOCAL_FCNTL);
2033                 else
2034                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
2035                                         NFS_MOUNT_LOCAL_FCNTL);
2036                 /*
2037                  * The legacy version 6 binary mount data from userspace has a
2038                  * field used only to transport selinux information into the
2039                  * the kernel.  To continue to support that functionality we
2040                  * have a touch of selinux knowledge here in the NFS code. The
2041                  * userspace code converted context=blah to just blah so we are
2042                  * converting back to the full string selinux understands.
2043                  */
2044                 if (data->context[0]){
2045 #ifdef CONFIG_SECURITY_SELINUX
2046                         int rc;
2047                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
2048                         if (!opts_str)
2049                                 return -ENOMEM;
2050                         strcpy(opts_str, "context=");
2051                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
2052                         strcat(opts_str, &data->context[0]);
2053                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
2054                         kfree(opts_str);
2055                         if (rc)
2056                                 return rc;
2057 #else
2058                         return -EINVAL;
2059 #endif
2060                 }
2061
2062                 break;
2063         default:
2064                 return NFS_TEXT_DATA;
2065         }
2066
2067         return 0;
2068
2069 out_no_data:
2070         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2071         return -EINVAL;
2072
2073 out_no_v3:
2074         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2075                  data->version);
2076         return -EINVAL;
2077
2078 out_no_sec:
2079         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2080         return -EINVAL;
2081
2082 out_nomem:
2083         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2084         return -ENOMEM;
2085
2086 out_no_address:
2087         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2088         return -EINVAL;
2089
2090 out_invalid_fh:
2091         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2092         return -EINVAL;
2093 }
2094
2095 #if IS_ENABLED(CONFIG_NFS_V4)
2096 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2097                                    void *options,
2098                                    struct nfs_parsed_mount_data *args,
2099                                    struct nfs_fh *mntfh,
2100                                    const char *dev_name)
2101 {
2102         if (fs_type == &nfs_fs_type)
2103                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2104         return nfs4_validate_mount_data(options, args, dev_name);
2105 }
2106 #else
2107 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2108                                    void *options,
2109                                    struct nfs_parsed_mount_data *args,
2110                                    struct nfs_fh *mntfh,
2111                                    const char *dev_name)
2112 {
2113         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2114 }
2115 #endif
2116
2117 static int nfs_validate_text_mount_data(void *options,
2118                                         struct nfs_parsed_mount_data *args,
2119                                         const char *dev_name)
2120 {
2121         int port = 0;
2122         int max_namelen = PAGE_SIZE;
2123         int max_pathlen = NFS_MAXPATHLEN;
2124         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2125
2126         if (nfs_parse_mount_options((char *)options, args) == 0)
2127                 return -EINVAL;
2128
2129         if (!nfs_verify_server_address(sap))
2130                 goto out_no_address;
2131
2132         if (args->version == 4) {
2133 #if IS_ENABLED(CONFIG_NFS_V4)
2134                 port = NFS_PORT;
2135                 max_namelen = NFS4_MAXNAMLEN;
2136                 max_pathlen = NFS4_MAXPATHLEN;
2137                 nfs_validate_transport_protocol(args);
2138                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2139                         goto out_invalid_transport_udp;
2140                 nfs4_validate_mount_flags(args);
2141 #else
2142                 goto out_v4_not_compiled;
2143 #endif /* CONFIG_NFS_V4 */
2144         } else
2145                 nfs_set_mount_transport_protocol(args);
2146
2147         nfs_set_port(sap, &args->nfs_server.port, port);
2148
2149         return nfs_parse_devname(dev_name,
2150                                    &args->nfs_server.hostname,
2151                                    max_namelen,
2152                                    &args->nfs_server.export_path,
2153                                    max_pathlen);
2154
2155 #if !IS_ENABLED(CONFIG_NFS_V4)
2156 out_v4_not_compiled:
2157         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2158         return -EPROTONOSUPPORT;
2159 #else
2160 out_invalid_transport_udp:
2161         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2162         return -EINVAL;
2163 #endif /* !CONFIG_NFS_V4 */
2164
2165 out_no_address:
2166         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2167         return -EINVAL;
2168 }
2169
2170 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
2171                 | NFS_MOUNT_SECURE \
2172                 | NFS_MOUNT_TCP \
2173                 | NFS_MOUNT_VER3 \
2174                 | NFS_MOUNT_KERBEROS \
2175                 | NFS_MOUNT_NONLM \
2176                 | NFS_MOUNT_BROKEN_SUID \
2177                 | NFS_MOUNT_STRICTLOCK \
2178                 | NFS_MOUNT_LEGACY_INTERFACE)
2179
2180 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
2181                 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
2182
2183 static int
2184 nfs_compare_remount_data(struct nfs_server *nfss,
2185                          struct nfs_parsed_mount_data *data)
2186 {
2187         if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
2188             data->rsize != nfss->rsize ||
2189             data->wsize != nfss->wsize ||
2190             data->version != nfss->nfs_client->rpc_ops->version ||
2191             data->minorversion != nfss->nfs_client->cl_minorversion ||
2192             data->retrans != nfss->client->cl_timeout->to_retries ||
2193             data->selected_flavor != nfss->client->cl_auth->au_flavor ||
2194             data->acregmin != nfss->acregmin / HZ ||
2195             data->acregmax != nfss->acregmax / HZ ||
2196             data->acdirmin != nfss->acdirmin / HZ ||
2197             data->acdirmax != nfss->acdirmax / HZ ||
2198             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2199             data->nfs_server.port != nfss->port ||
2200             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2201             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2202                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2203                 return -EINVAL;
2204
2205         return 0;
2206 }
2207
2208 int
2209 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2210 {
2211         int error;
2212         struct nfs_server *nfss = sb->s_fs_info;
2213         struct nfs_parsed_mount_data *data;
2214         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2215         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2216         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2217
2218         sync_filesystem(sb);
2219
2220         /*
2221          * Userspace mount programs that send binary options generally send
2222          * them populated with default values. We have no way to know which
2223          * ones were explicitly specified. Fall back to legacy behavior and
2224          * just return success.
2225          */
2226         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2227             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2228                                            options->version <= 6))))
2229                 return 0;
2230
2231         data = kzalloc(sizeof(*data), GFP_KERNEL);
2232         if (data == NULL)
2233                 return -ENOMEM;
2234
2235         /* fill out struct with values from existing mount */
2236         data->flags = nfss->flags;
2237         data->rsize = nfss->rsize;
2238         data->wsize = nfss->wsize;
2239         data->retrans = nfss->client->cl_timeout->to_retries;
2240         data->selected_flavor = nfss->client->cl_auth->au_flavor;
2241         data->auth_info = nfss->auth_info;
2242         data->acregmin = nfss->acregmin / HZ;
2243         data->acregmax = nfss->acregmax / HZ;
2244         data->acdirmin = nfss->acdirmin / HZ;
2245         data->acdirmax = nfss->acdirmax / HZ;
2246         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2247         data->nfs_server.port = nfss->port;
2248         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2249         data->version = nfsvers;
2250         data->minorversion = nfss->nfs_client->cl_minorversion;
2251         data->net = current->nsproxy->net_ns;
2252         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2253                 data->nfs_server.addrlen);
2254
2255         /* overwrite those values with any that were specified */
2256         error = -EINVAL;
2257         if (!nfs_parse_mount_options((char *)options, data))
2258                 goto out;
2259
2260         /*
2261          * noac is a special case. It implies -o sync, but that's not
2262          * necessarily reflected in the mtab options. do_remount_sb
2263          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2264          * remount options, so we have to explicitly reset it.
2265          */
2266         if (data->flags & NFS_MOUNT_NOAC)
2267                 *flags |= MS_SYNCHRONOUS;
2268
2269         /* compare new mount options with old ones */
2270         error = nfs_compare_remount_data(nfss, data);
2271 out:
2272         kfree(data);
2273         return error;
2274 }
2275 EXPORT_SYMBOL_GPL(nfs_remount);
2276
2277 /*
2278  * Initialise the common bits of the superblock
2279  */
2280 inline void nfs_initialise_sb(struct super_block *sb)
2281 {
2282         struct nfs_server *server = NFS_SB(sb);
2283
2284         sb->s_magic = NFS_SUPER_MAGIC;
2285
2286         /* We probably want something more informative here */
2287         snprintf(sb->s_id, sizeof(sb->s_id),
2288                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2289
2290         if (sb->s_blocksize == 0)
2291                 sb->s_blocksize = nfs_block_bits(server->wsize,
2292                                                  &sb->s_blocksize_bits);
2293
2294         sb->s_bdi = &server->backing_dev_info;
2295
2296         nfs_super_set_maxbytes(sb, server->maxfilesize);
2297 }
2298
2299 /*
2300  * Finish setting up an NFS2/3 superblock
2301  */
2302 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2303 {
2304         struct nfs_parsed_mount_data *data = mount_info->parsed;
2305         struct nfs_server *server = NFS_SB(sb);
2306
2307         sb->s_blocksize_bits = 0;
2308         sb->s_blocksize = 0;
2309         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2310         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2311         if (data && data->bsize)
2312                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2313
2314         if (server->nfs_client->rpc_ops->version != 2) {
2315                 /* The VFS shouldn't apply the umask to mode bits. We will do
2316                  * so ourselves when necessary.
2317                  */
2318                 sb->s_flags |= MS_POSIXACL;
2319                 sb->s_time_gran = 1;
2320         }
2321
2322         nfs_initialise_sb(sb);
2323 }
2324 EXPORT_SYMBOL_GPL(nfs_fill_super);
2325
2326 /*
2327  * Finish setting up a cloned NFS2/3/4 superblock
2328  */
2329 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2330 {
2331         const struct super_block *old_sb = mount_info->cloned->sb;
2332         struct nfs_server *server = NFS_SB(sb);
2333
2334         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2335         sb->s_blocksize = old_sb->s_blocksize;
2336         sb->s_maxbytes = old_sb->s_maxbytes;
2337         sb->s_xattr = old_sb->s_xattr;
2338         sb->s_op = old_sb->s_op;
2339         sb->s_time_gran = 1;
2340
2341         if (server->nfs_client->rpc_ops->version != 2) {
2342                 /* The VFS shouldn't apply the umask to mode bits. We will do
2343                  * so ourselves when necessary.
2344                  */
2345                 sb->s_flags |= MS_POSIXACL;
2346         }
2347
2348         nfs_initialise_sb(sb);
2349 }
2350
2351 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2352 {
2353         const struct nfs_server *a = s->s_fs_info;
2354         const struct rpc_clnt *clnt_a = a->client;
2355         const struct rpc_clnt *clnt_b = b->client;
2356
2357         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2358                 goto Ebusy;
2359         if (a->nfs_client != b->nfs_client)
2360                 goto Ebusy;
2361         if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
2362                 goto Ebusy;
2363         if (a->wsize != b->wsize)
2364                 goto Ebusy;
2365         if (a->rsize != b->rsize)
2366                 goto Ebusy;
2367         if (a->acregmin != b->acregmin)
2368                 goto Ebusy;
2369         if (a->acregmax != b->acregmax)
2370                 goto Ebusy;
2371         if (a->acdirmin != b->acdirmin)
2372                 goto Ebusy;
2373         if (a->acdirmax != b->acdirmax)
2374                 goto Ebusy;
2375         if (b->auth_info.flavor_len > 0 &&
2376            clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2377                 goto Ebusy;
2378         return 1;
2379 Ebusy:
2380         return 0;
2381 }
2382
2383 struct nfs_sb_mountdata {
2384         struct nfs_server *server;
2385         int mntflags;
2386 };
2387
2388 static int nfs_set_super(struct super_block *s, void *data)
2389 {
2390         struct nfs_sb_mountdata *sb_mntdata = data;
2391         struct nfs_server *server = sb_mntdata->server;
2392         int ret;
2393
2394         s->s_flags = sb_mntdata->mntflags;
2395         s->s_fs_info = server;
2396         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2397         ret = set_anon_super(s, server);
2398         if (ret == 0)
2399                 server->s_dev = s->s_dev;
2400         return ret;
2401 }
2402
2403 static int nfs_compare_super_address(struct nfs_server *server1,
2404                                      struct nfs_server *server2)
2405 {
2406         struct sockaddr *sap1, *sap2;
2407
2408         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2409         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2410
2411         if (sap1->sa_family != sap2->sa_family)
2412                 return 0;
2413
2414         switch (sap1->sa_family) {
2415         case AF_INET: {
2416                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2417                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2418                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2419                         return 0;
2420                 if (sin1->sin_port != sin2->sin_port)
2421                         return 0;
2422                 break;
2423         }
2424         case AF_INET6: {
2425                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2426                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2427                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2428                         return 0;
2429                 if (sin1->sin6_port != sin2->sin6_port)
2430                         return 0;
2431                 break;
2432         }
2433         default:
2434                 return 0;
2435         }
2436
2437         return 1;
2438 }
2439
2440 static int nfs_compare_super(struct super_block *sb, void *data)
2441 {
2442         struct nfs_sb_mountdata *sb_mntdata = data;
2443         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2444         int mntflags = sb_mntdata->mntflags;
2445
2446         if (!nfs_compare_super_address(old, server))
2447                 return 0;
2448         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2449         if (old->flags & NFS_MOUNT_UNSHARED)
2450                 return 0;
2451         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2452                 return 0;
2453         return nfs_compare_mount_options(sb, server, mntflags);
2454 }
2455
2456 #ifdef CONFIG_NFS_FSCACHE
2457 static void nfs_get_cache_cookie(struct super_block *sb,
2458                                  struct nfs_parsed_mount_data *parsed,
2459                                  struct nfs_clone_mount *cloned)
2460 {
2461         struct nfs_server *nfss = NFS_SB(sb);
2462         char *uniq = NULL;
2463         int ulen = 0;
2464
2465         nfss->fscache_key = NULL;
2466         nfss->fscache = NULL;
2467
2468         if (parsed) {
2469                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2470                         return;
2471                 if (parsed->fscache_uniq) {
2472                         uniq = parsed->fscache_uniq;
2473                         ulen = strlen(parsed->fscache_uniq);
2474                 }
2475         } else if (cloned) {
2476                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2477                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2478                         return;
2479                 if (mnt_s->fscache_key) {
2480                         uniq = mnt_s->fscache_key->key.uniquifier;
2481                         ulen = mnt_s->fscache_key->key.uniq_len;
2482                 };
2483         } else
2484                 return;
2485
2486         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2487 }
2488 #else
2489 static void nfs_get_cache_cookie(struct super_block *sb,
2490                                  struct nfs_parsed_mount_data *parsed,
2491                                  struct nfs_clone_mount *cloned)
2492 {
2493 }
2494 #endif
2495
2496 static int nfs_bdi_register(struct nfs_server *server)
2497 {
2498         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2499 }
2500
2501 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2502                         struct nfs_mount_info *mount_info)
2503 {
2504         int error;
2505         unsigned long kflags = 0, kflags_out = 0;
2506         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2507                 kflags |= SECURITY_LSM_NATIVE_LABELS;
2508
2509         error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
2510                                                 kflags, &kflags_out);
2511         if (error)
2512                 goto err;
2513
2514         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2515                 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2516                 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2517 err:
2518         return error;
2519 }
2520 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2521
2522 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2523                           struct nfs_mount_info *mount_info)
2524 {
2525         /* clone any lsm security options from the parent to the new sb */
2526         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2527                 return -ESTALE;
2528         return security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2529 }
2530 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2531
2532 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2533                                    int flags, const char *dev_name,
2534                                    struct nfs_mount_info *mount_info,
2535                                    struct nfs_subversion *nfs_mod)
2536 {
2537         struct super_block *s;
2538         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2539         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2540         struct nfs_sb_mountdata sb_mntdata = {
2541                 .mntflags = flags,
2542                 .server = server,
2543         };
2544         int error;
2545
2546         if (server->flags & NFS_MOUNT_UNSHARED)
2547                 compare_super = NULL;
2548
2549         /* -o noac implies -o sync */
2550         if (server->flags & NFS_MOUNT_NOAC)
2551                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2552
2553         if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
2554                 if (mount_info->cloned->sb->s_flags & MS_SYNCHRONOUS)
2555                         sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2556
2557         /* Get a superblock - note that we may end up sharing one that already exists */
2558         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2559         if (IS_ERR(s)) {
2560                 mntroot = ERR_CAST(s);
2561                 goto out_err_nosb;
2562         }
2563
2564         if (s->s_fs_info != server) {
2565                 nfs_free_server(server);
2566                 server = NULL;
2567         } else {
2568                 error = nfs_bdi_register(server);
2569                 if (error) {
2570                         mntroot = ERR_PTR(error);
2571                         goto error_splat_super;
2572                 }
2573                 server->super = s;
2574         }
2575
2576         if (!s->s_root) {
2577                 /* initial superblock/root creation */
2578                 mount_info->fill_super(s, mount_info);
2579                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2580         }
2581
2582         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2583         if (IS_ERR(mntroot))
2584                 goto error_splat_super;
2585
2586         error = mount_info->set_security(s, mntroot, mount_info);
2587         if (error)
2588                 goto error_splat_root;
2589
2590         s->s_flags |= MS_ACTIVE;
2591
2592 out:
2593         return mntroot;
2594
2595 out_err_nosb:
2596         nfs_free_server(server);
2597         goto out;
2598
2599 error_splat_root:
2600         dput(mntroot);
2601         mntroot = ERR_PTR(error);
2602 error_splat_super:
2603         deactivate_locked_super(s);
2604         goto out;
2605 }
2606 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2607
2608 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2609         int flags, const char *dev_name, void *raw_data)
2610 {
2611         struct nfs_mount_info mount_info = {
2612                 .fill_super = nfs_fill_super,
2613                 .set_security = nfs_set_sb_security,
2614         };
2615         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2616         struct nfs_subversion *nfs_mod;
2617         int error;
2618
2619         mount_info.parsed = nfs_alloc_parsed_mount_data();
2620         mount_info.mntfh = nfs_alloc_fhandle();
2621         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2622                 goto out;
2623
2624         /* Validate the mount data */
2625         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2626         if (error == NFS_TEXT_DATA)
2627                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2628         if (error < 0) {
2629                 mntroot = ERR_PTR(error);
2630                 goto out;
2631         }
2632
2633         nfs_mod = get_nfs_version(mount_info.parsed->version);
2634         if (IS_ERR(nfs_mod)) {
2635                 mntroot = ERR_CAST(nfs_mod);
2636                 goto out;
2637         }
2638
2639         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2640
2641         put_nfs_version(nfs_mod);
2642 out:
2643         nfs_free_parsed_mount_data(mount_info.parsed);
2644         nfs_free_fhandle(mount_info.mntfh);
2645         return mntroot;
2646 }
2647 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2648
2649 /*
2650  * Destroy an NFS2/3 superblock
2651  */
2652 void nfs_kill_super(struct super_block *s)
2653 {
2654         struct nfs_server *server = NFS_SB(s);
2655         dev_t dev = s->s_dev;
2656
2657         generic_shutdown_super(s);
2658
2659         nfs_fscache_release_super_cookie(s);
2660
2661         nfs_free_server(server);
2662         free_anon_bdev(dev);
2663 }
2664 EXPORT_SYMBOL_GPL(nfs_kill_super);
2665
2666 /*
2667  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2668  */
2669 static struct dentry *
2670 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2671                 const char *dev_name, void *raw_data)
2672 {
2673         struct nfs_clone_mount *data = raw_data;
2674         struct nfs_mount_info mount_info = {
2675                 .fill_super = nfs_clone_super,
2676                 .set_security = nfs_clone_sb_security,
2677                 .cloned = data,
2678         };
2679         struct nfs_server *server;
2680         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2681         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2682
2683         dprintk("--> nfs_xdev_mount()\n");
2684
2685         mount_info.mntfh = mount_info.cloned->fh;
2686
2687         /* create a new volume representation */
2688         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2689
2690         if (IS_ERR(server))
2691                 mntroot = ERR_CAST(server);
2692         else
2693                 mntroot = nfs_fs_mount_common(server, flags,
2694                                 dev_name, &mount_info, nfs_mod);
2695
2696         dprintk("<-- nfs_xdev_mount() = %ld\n",
2697                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2698         return mntroot;
2699 }
2700
2701 #if IS_ENABLED(CONFIG_NFS_V4)
2702
2703 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2704 {
2705         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2706                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2707 }
2708
2709 /*
2710  * Validate NFSv4 mount options
2711  */
2712 static int nfs4_validate_mount_data(void *options,
2713                                     struct nfs_parsed_mount_data *args,
2714                                     const char *dev_name)
2715 {
2716         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2717         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2718         char *c;
2719
2720         if (data == NULL)
2721                 goto out_no_data;
2722
2723         args->version = 4;
2724
2725         switch (data->version) {
2726         case 1:
2727                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2728                         goto out_no_address;
2729                 if (data->host_addrlen == 0)
2730                         goto out_no_address;
2731                 args->nfs_server.addrlen = data->host_addrlen;
2732                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2733                         return -EFAULT;
2734                 if (!nfs_verify_server_address(sap))
2735                         goto out_no_address;
2736                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2737
2738                 if (data->auth_flavourlen) {
2739                         rpc_authflavor_t pseudoflavor;
2740                         if (data->auth_flavourlen > 1)
2741                                 goto out_inval_auth;
2742                         if (copy_from_user(&pseudoflavor,
2743                                            data->auth_flavours,
2744                                            sizeof(pseudoflavor)))
2745                                 return -EFAULT;
2746                         args->selected_flavor = pseudoflavor;
2747                 } else
2748                         args->selected_flavor = RPC_AUTH_UNIX;
2749
2750                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2751                 if (IS_ERR(c))
2752                         return PTR_ERR(c);
2753                 args->nfs_server.hostname = c;
2754
2755                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2756                 if (IS_ERR(c))
2757                         return PTR_ERR(c);
2758                 args->nfs_server.export_path = c;
2759                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2760
2761                 c = strndup_user(data->client_addr.data, 16);
2762                 if (IS_ERR(c))
2763                         return PTR_ERR(c);
2764                 args->client_address = c;
2765
2766                 /*
2767                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2768                  * can deal with.
2769                  */
2770
2771                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2772                 args->rsize     = data->rsize;
2773                 args->wsize     = data->wsize;
2774                 args->timeo     = data->timeo;
2775                 args->retrans   = data->retrans;
2776                 args->acregmin  = data->acregmin;
2777                 args->acregmax  = data->acregmax;
2778                 args->acdirmin  = data->acdirmin;
2779                 args->acdirmax  = data->acdirmax;
2780                 args->nfs_server.protocol = data->proto;
2781                 nfs_validate_transport_protocol(args);
2782                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2783                         goto out_invalid_transport_udp;
2784
2785                 break;
2786         default:
2787                 return NFS_TEXT_DATA;
2788         }
2789
2790         return 0;
2791
2792 out_no_data:
2793         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2794         return -EINVAL;
2795
2796 out_inval_auth:
2797         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2798                  data->auth_flavourlen);
2799         return -EINVAL;
2800
2801 out_no_address:
2802         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2803         return -EINVAL;
2804
2805 out_invalid_transport_udp:
2806         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2807         return -EINVAL;
2808 }
2809
2810 /*
2811  * NFS v4 module parameters need to stay in the
2812  * NFS client for backwards compatibility
2813  */
2814 unsigned int nfs_callback_set_tcpport;
2815 unsigned short nfs_callback_tcpport;
2816 /* Default cache timeout is 10 minutes */
2817 unsigned int nfs_idmap_cache_timeout = 600;
2818 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2819 bool nfs4_disable_idmapping = true;
2820 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2821 unsigned short send_implementation_id = 1;
2822 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2823 bool recover_lost_locks = false;
2824
2825 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2826 EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2827 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2828 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2829 EXPORT_SYMBOL_GPL(max_session_slots);
2830 EXPORT_SYMBOL_GPL(send_implementation_id);
2831 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2832 EXPORT_SYMBOL_GPL(recover_lost_locks);
2833
2834 #define NFS_CALLBACK_MAXPORTNR (65535U)
2835
2836 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2837 {
2838         unsigned long num;
2839         int ret;
2840
2841         if (!val)
2842                 return -EINVAL;
2843         ret = kstrtoul(val, 0, &num);
2844         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2845                 return -EINVAL;
2846         *((unsigned int *)kp->arg) = num;
2847         return 0;
2848 }
2849 static struct kernel_param_ops param_ops_portnr = {
2850         .set = param_set_portnr,
2851         .get = param_get_uint,
2852 };
2853 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2854
2855 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2856 module_param(nfs_idmap_cache_timeout, int, 0644);
2857 module_param(nfs4_disable_idmapping, bool, 0644);
2858 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2859                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2860 MODULE_PARM_DESC(nfs4_disable_idmapping,
2861                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2862 module_param(max_session_slots, ushort, 0644);
2863 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2864                 "requests the client will negotiate");
2865 module_param(send_implementation_id, ushort, 0644);
2866 MODULE_PARM_DESC(send_implementation_id,
2867                 "Send implementation ID with NFSv4.1 exchange_id");
2868 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2869
2870 module_param(recover_lost_locks, bool, 0644);
2871 MODULE_PARM_DESC(recover_lost_locks,
2872                  "If the server reports that a lock might be lost, "
2873                  "try to recover it risking data corruption.");
2874
2875
2876 #endif /* CONFIG_NFS_V4 */