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/stats.h>
  35 #include <linux/sunrpc/metrics.h>
  36 #include <linux/sunrpc/xprtsock.h>
  37 #include <linux/sunrpc/xprtrdma.h>
  38 #include <linux/nfs_fs.h>
  39 #include <linux/nfs_mount.h>
  40 #include <linux/nfs4_mount.h>
  41 #include <linux/lockd/bind.h>
  42 #include <linux/seq_file.h>
  43 #include <linux/mount.h>
  44 #include <linux/namei.h>
  45 #include <linux/nfs_idmap.h>
  46 #include <linux/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <linux/slab.h>
  50 #include <net/ipv6.h>
  51 #include <linux/netdevice.h>
  52 #include <linux/nfs_xdr.h>
  53 #include <linux/magic.h>
  54 #include <linux/parser.h>
  55 #include <linux/nsproxy.h>
  56 #include <linux/rcupdate.h>
  57
  58 #include <asm/uaccess.h>
  59
  60 #include "nfs4_fs.h"
  61 #include "callback.h"
  62 #include "delegation.h"
  63 #include "iostat.h"
  64 #include "internal.h"
  65 #include "fscache.h"
  66 #include "nfs4session.h"
  67 #include "pnfs.h"
  68 #include "nfs.h"
  69
  70 #define NFSDBG_FACILITY         NFSDBG_VFS
  71 #define NFS_TEXT_DATA           1
  72
  73 #if IS_ENABLED(CONFIG_NFS_V3)
  74 #define NFS_DEFAULT_VERSION 3
  75 #else
  76 #define NFS_DEFAULT_VERSION 2
  77 #endif
  78
  79 enum {
  80         /* Mount options that take no arguments */
  81         Opt_soft, Opt_hard,
  82         Opt_posix, Opt_noposix,
  83         Opt_cto, Opt_nocto,
  84         Opt_ac, Opt_noac,
  85         Opt_lock, Opt_nolock,
  86         Opt_udp, Opt_tcp, Opt_rdma,
  87         Opt_acl, Opt_noacl,
  88         Opt_rdirplus, Opt_nordirplus,
  89         Opt_sharecache, Opt_nosharecache,
  90         Opt_resvport, Opt_noresvport,
  91         Opt_fscache, Opt_nofscache,
  92         Opt_migration, Opt_nomigration,
  93
  94         /* Mount options that take integer arguments */
  95         Opt_port,
  96         Opt_rsize, Opt_wsize, Opt_bsize,
  97         Opt_timeo, Opt_retrans,
  98         Opt_acregmin, Opt_acregmax,
  99         Opt_acdirmin, Opt_acdirmax,
 100         Opt_actimeo,
 101         Opt_namelen,
 102         Opt_mountport,
 103         Opt_mountvers,
 104         Opt_minorversion,
 105
 106         /* Mount options that take string arguments */
 107         Opt_nfsvers,
 108         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 109         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 110         Opt_lookupcache,
 111         Opt_fscache_uniq,
 112         Opt_local_lock,
 113
 114         /* Special mount options */
 115         Opt_userspace, Opt_deprecated, Opt_sloppy,
 116
 117         Opt_err
 118 };
 119
 120 static const match_table_t nfs_mount_option_tokens = {
 121         { Opt_userspace, "bg" },
 122         { Opt_userspace, "fg" },
 123         { Opt_userspace, "retry=%s" },
 124
 125         { Opt_sloppy, "sloppy" },
 126
 127         { Opt_soft, "soft" },
 128         { Opt_hard, "hard" },
 129         { Opt_deprecated, "intr" },
 130         { Opt_deprecated, "nointr" },
 131         { Opt_posix, "posix" },
 132         { Opt_noposix, "noposix" },
 133         { Opt_cto, "cto" },
 134         { Opt_nocto, "nocto" },
 135         { Opt_ac, "ac" },
 136         { Opt_noac, "noac" },
 137         { Opt_lock, "lock" },
 138         { Opt_nolock, "nolock" },
 139         { Opt_udp, "udp" },
 140         { Opt_tcp, "tcp" },
 141         { Opt_rdma, "rdma" },
 142         { Opt_acl, "acl" },
 143         { Opt_noacl, "noacl" },
 144         { Opt_rdirplus, "rdirplus" },
 145         { Opt_nordirplus, "nordirplus" },
 146         { Opt_sharecache, "sharecache" },
 147         { Opt_nosharecache, "nosharecache" },
 148         { Opt_resvport, "resvport" },
 149         { Opt_noresvport, "noresvport" },
 150         { Opt_fscache, "fsc" },
 151         { Opt_nofscache, "nofsc" },
 152         { Opt_migration, "migration" },
 153         { Opt_nomigration, "nomigration" },
 154
 155         { Opt_port, "port=%s" },
 156         { Opt_rsize, "rsize=%s" },
 157         { Opt_wsize, "wsize=%s" },
 158         { Opt_bsize, "bsize=%s" },
 159         { Opt_timeo, "timeo=%s" },
 160         { Opt_retrans, "retrans=%s" },
 161         { Opt_acregmin, "acregmin=%s" },
 162         { Opt_acregmax, "acregmax=%s" },
 163         { Opt_acdirmin, "acdirmin=%s" },
 164         { Opt_acdirmax, "acdirmax=%s" },
 165         { Opt_actimeo, "actimeo=%s" },
 166         { Opt_namelen, "namlen=%s" },
 167         { Opt_mountport, "mountport=%s" },
 168         { Opt_mountvers, "mountvers=%s" },
 169         { Opt_minorversion, "minorversion=%s" },
 170
 171         { Opt_nfsvers, "nfsvers=%s" },
 172         { Opt_nfsvers, "vers=%s" },
 173
 174         { Opt_sec, "sec=%s" },
 175         { Opt_proto, "proto=%s" },
 176         { Opt_mountproto, "mountproto=%s" },
 177         { Opt_addr, "addr=%s" },
 178         { Opt_clientaddr, "clientaddr=%s" },
 179         { Opt_mounthost, "mounthost=%s" },
 180         { Opt_mountaddr, "mountaddr=%s" },
 181
 182         { Opt_lookupcache, "lookupcache=%s" },
 183         { Opt_fscache_uniq, "fsc=%s" },
 184         { Opt_local_lock, "local_lock=%s" },
 185
 186         /* The following needs to be listed after all other options */
 187         { Opt_nfsvers, "v%s" },
 188
 189         { Opt_err, NULL }
 190 };
 191
 192 enum {
 193         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 194
 195         Opt_xprt_err
 196 };
 197
 198 static const match_table_t nfs_xprt_protocol_tokens = {
 199         { Opt_xprt_udp, "udp" },
 200         { Opt_xprt_udp6, "udp6" },
 201         { Opt_xprt_tcp, "tcp" },
 202         { Opt_xprt_tcp6, "tcp6" },
 203         { Opt_xprt_rdma, "rdma" },
 204
 205         { Opt_xprt_err, NULL }
 206 };
 207
 208 enum {
 209         Opt_sec_none, Opt_sec_sys,
 210         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 211         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 212         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 213
 214         Opt_sec_err
 215 };
 216
 217 static const match_table_t nfs_secflavor_tokens = {
 218         { Opt_sec_none, "none" },
 219         { Opt_sec_none, "null" },
 220         { Opt_sec_sys, "sys" },
 221
 222         { Opt_sec_krb5, "krb5" },
 223         { Opt_sec_krb5i, "krb5i" },
 224         { Opt_sec_krb5p, "krb5p" },
 225
 226         { Opt_sec_lkey, "lkey" },
 227         { Opt_sec_lkeyi, "lkeyi" },
 228         { Opt_sec_lkeyp, "lkeyp" },
 229
 230         { Opt_sec_spkm, "spkm3" },
 231         { Opt_sec_spkmi, "spkm3i" },
 232         { Opt_sec_spkmp, "spkm3p" },
 233
 234         { Opt_sec_err, NULL }
 235 };
 236
 237 enum {
 238         Opt_lookupcache_all, Opt_lookupcache_positive,
 239         Opt_lookupcache_none,
 240
 241         Opt_lookupcache_err
 242 };
 243
 244 static match_table_t nfs_lookupcache_tokens = {
 245         { Opt_lookupcache_all, "all" },
 246         { Opt_lookupcache_positive, "pos" },
 247         { Opt_lookupcache_positive, "positive" },
 248         { Opt_lookupcache_none, "none" },
 249
 250         { Opt_lookupcache_err, NULL }
 251 };
 252
 253 enum {
 254         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 255         Opt_local_lock_none,
 256
 257         Opt_local_lock_err
 258 };
 259
 260 static match_table_t nfs_local_lock_tokens = {
 261         { Opt_local_lock_all, "all" },
 262         { Opt_local_lock_flock, "flock" },
 263         { Opt_local_lock_posix, "posix" },
 264         { Opt_local_lock_none, "none" },
 265
 266         { Opt_local_lock_err, NULL }
 267 };
 268
 269 enum {
 270         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 271         Opt_vers_4_1,
 272
 273         Opt_vers_err
 274 };
 275
 276 static match_table_t nfs_vers_tokens = {
 277         { Opt_vers_2, "2" },
 278         { Opt_vers_3, "3" },
 279         { Opt_vers_4, "4" },
 280         { Opt_vers_4_0, "4.0" },
 281         { Opt_vers_4_1, "4.1" },
 282
 283         { Opt_vers_err, NULL }
 284 };
 285
 286 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 287                 int flags, const char *dev_name, void *raw_data);
 288
 289 struct file_system_type nfs_fs_type = {
 290         .owner          = THIS_MODULE,
 291         .name           = "nfs",
 292         .mount          = nfs_fs_mount,
 293         .kill_sb        = nfs_kill_super,
 294         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 295 };
 296 EXPORT_SYMBOL_GPL(nfs_fs_type);
 297
 298 struct file_system_type nfs_xdev_fs_type = {
 299         .owner          = THIS_MODULE,
 300         .name           = "nfs",
 301         .mount          = nfs_xdev_mount,
 302         .kill_sb        = nfs_kill_super,
 303         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 304 };
 305
 306 const struct super_operations nfs_sops = {
 307         .alloc_inode    = nfs_alloc_inode,
 308         .destroy_inode  = nfs_destroy_inode,
 309         .write_inode    = nfs_write_inode,
 310         .drop_inode     = nfs_drop_inode,
 311         .put_super      = nfs_put_super,
 312         .statfs         = nfs_statfs,
 313         .evict_inode    = nfs_evict_inode,
 314         .umount_begin   = nfs_umount_begin,
 315         .show_options   = nfs_show_options,
 316         .show_devname   = nfs_show_devname,
 317         .show_path      = nfs_show_path,
 318         .show_stats     = nfs_show_stats,
 319         .remount_fs     = nfs_remount,
 320 };
 321 EXPORT_SYMBOL_GPL(nfs_sops);
 322
 323 #if IS_ENABLED(CONFIG_NFS_V4)
 324 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 325 static int nfs4_validate_mount_data(void *options,
 326         struct nfs_parsed_mount_data *args, const char *dev_name);
 327
 328 struct file_system_type nfs4_fs_type = {
 329         .owner          = THIS_MODULE,
 330         .name           = "nfs4",
 331         .mount          = nfs_fs_mount,
 332         .kill_sb        = nfs_kill_super,
 333         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 334 };
 335 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 336
 337 static int __init register_nfs4_fs(void)
 338 {
 339         return register_filesystem(&nfs4_fs_type);
 340 }
 341
 342 static void unregister_nfs4_fs(void)
 343 {
 344         unregister_filesystem(&nfs4_fs_type);
 345 }
 346 #else
 347 static int __init register_nfs4_fs(void)
 348 {
 349         return 0;
 350 }
 351
 352 static void unregister_nfs4_fs(void)
 353 {
 354 }
 355 #endif
 356
 357 static struct shrinker acl_shrinker = {
 358         .shrink         = nfs_access_cache_shrinker,
 359         .seeks          = DEFAULT_SEEKS,
 360 };
 361
 362 /*
 363  * Register the NFS filesystems
 364  */
 365 int __init register_nfs_fs(void)
 366 {
 367         int ret;
 368
 369         ret = register_filesystem(&nfs_fs_type);
 370         if (ret < 0)
 371                 goto error_0;
 372
 373         ret = register_nfs4_fs();
 374         if (ret < 0)
 375                 goto error_1;
 376
 377         ret = nfs_register_sysctl();
 378         if (ret < 0)
 379                 goto error_2;
 380         register_shrinker(&acl_shrinker);
 381         return 0;
 382
 383 error_2:
 384         unregister_nfs4_fs();
 385 error_1:
 386         unregister_filesystem(&nfs_fs_type);
 387 error_0:
 388         return ret;
 389 }
 390
 391 /*
 392  * Unregister the NFS filesystems
 393  */
 394 void __exit unregister_nfs_fs(void)
 395 {
 396         unregister_shrinker(&acl_shrinker);
 397         nfs_unregister_sysctl();
 398         unregister_nfs4_fs();
 399         unregister_filesystem(&nfs_fs_type);
 400 }
 401
 402 void nfs_sb_active(struct super_block *sb)
 403 {
 404         struct nfs_server *server = NFS_SB(sb);
 405
 406         if (atomic_inc_return(&server->active) == 1)
 407                 atomic_inc(&sb->s_active);
 408 }
 409 EXPORT_SYMBOL_GPL(nfs_sb_active);
 410
 411 void nfs_sb_deactive(struct super_block *sb)
 412 {
 413         struct nfs_server *server = NFS_SB(sb);
 414
 415         if (atomic_dec_and_test(&server->active))
 416                 deactivate_super(sb);
 417 }
 418 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 419
 420 /*
 421  * Deliver file system statistics to userspace
 422  */
 423 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 424 {
 425         struct nfs_server *server = NFS_SB(dentry->d_sb);
 426         unsigned char blockbits;
 427         unsigned long blockres;
 428         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 429         struct nfs_fsstat res;
 430         int error = -ENOMEM;
 431
 432         res.fattr = nfs_alloc_fattr();
 433         if (res.fattr == NULL)
 434                 goto out_err;
 435
 436         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 437         if (unlikely(error == -ESTALE)) {
 438                 struct dentry *pd_dentry;
 439
 440                 pd_dentry = dget_parent(dentry);
 441                 if (pd_dentry != NULL) {
 442                         nfs_zap_caches(pd_dentry->d_inode);
 443                         dput(pd_dentry);
 444                 }
 445         }
 446         nfs_free_fattr(res.fattr);
 447         if (error < 0)
 448                 goto out_err;
 449
 450         buf->f_type = NFS_SUPER_MAGIC;
 451
 452         /*
 453          * Current versions of glibc do not correctly handle the
 454          * case where f_frsize != f_bsize.  Eventually we want to
 455          * report the value of wtmult in this field.
 456          */
 457         buf->f_frsize = dentry->d_sb->s_blocksize;
 458
 459         /*
 460          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 461          * are reported in units of f_frsize.  Linux hasn't had
 462          * an f_frsize field in its statfs struct until recently,
 463          * thus historically Linux's sys_statfs reports these
 464          * fields in units of f_bsize.
 465          */
 466         buf->f_bsize = dentry->d_sb->s_blocksize;
 467         blockbits = dentry->d_sb->s_blocksize_bits;
 468         blockres = (1 << blockbits) - 1;
 469         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 470         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 471         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 472
 473         buf->f_files = res.tfiles;
 474         buf->f_ffree = res.afiles;
 475
 476         buf->f_namelen = server->namelen;
 477
 478         return 0;
 479
 480  out_err:
 481         dprintk("%s: statfs error = %d\n", __func__, -error);
 482         return error;
 483 }
 484 EXPORT_SYMBOL_GPL(nfs_statfs);
 485
 486 /*
 487  * Map the security flavour number to a name
 488  */
 489 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 490 {
 491         static const struct {
 492                 rpc_authflavor_t flavour;
 493                 const char *str;
 494         } sec_flavours[] = {
 495                 { RPC_AUTH_NULL, "null" },
 496                 { RPC_AUTH_UNIX, "sys" },
 497                 { RPC_AUTH_GSS_KRB5, "krb5" },
 498                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 499                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 500                 { RPC_AUTH_GSS_LKEY, "lkey" },
 501                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 502                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 503                 { RPC_AUTH_GSS_SPKM, "spkm" },
 504                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 505                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 506                 { UINT_MAX, "unknown" }
 507         };
 508         int i;
 509
 510         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 511                 if (sec_flavours[i].flavour == flavour)
 512                         break;
 513         }
 514         return sec_flavours[i].str;
 515 }
 516
 517 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 518                                   int showdefaults)
 519 {
 520         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 521
 522         seq_printf(m, ",mountproto=");
 523         switch (sap->sa_family) {
 524         case AF_INET:
 525                 switch (nfss->mountd_protocol) {
 526                 case IPPROTO_UDP:
 527                         seq_printf(m, RPCBIND_NETID_UDP);
 528                         break;
 529                 case IPPROTO_TCP:
 530                         seq_printf(m, RPCBIND_NETID_TCP);
 531                         break;
 532                 default:
 533                         if (showdefaults)
 534                                 seq_printf(m, "auto");
 535                 }
 536                 break;
 537         case AF_INET6:
 538                 switch (nfss->mountd_protocol) {
 539                 case IPPROTO_UDP:
 540                         seq_printf(m, RPCBIND_NETID_UDP6);
 541                         break;
 542                 case IPPROTO_TCP:
 543                         seq_printf(m, RPCBIND_NETID_TCP6);
 544                         break;
 545                 default:
 546                         if (showdefaults)
 547                                 seq_printf(m, "auto");
 548                 }
 549                 break;
 550         default:
 551                 if (showdefaults)
 552                         seq_printf(m, "auto");
 553         }
 554 }
 555
 556 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 557                                     int showdefaults)
 558 {
 559         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 560
 561         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 562                 return;
 563
 564         switch (sap->sa_family) {
 565         case AF_INET: {
 566                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 567                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 568                 break;
 569         }
 570         case AF_INET6: {
 571                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 572                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 573                 break;
 574         }
 575         default:
 576                 if (showdefaults)
 577                         seq_printf(m, ",mountaddr=unspecified");
 578         }
 579
 580         if (nfss->mountd_version || showdefaults)
 581                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 582         if ((nfss->mountd_port &&
 583                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 584                 showdefaults)
 585                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 586
 587         nfs_show_mountd_netid(m, nfss, showdefaults);
 588 }
 589
 590 #if IS_ENABLED(CONFIG_NFS_V4)
 591 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 592                                     int showdefaults)
 593 {
 594         struct nfs_client *clp = nfss->nfs_client;
 595
 596         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 597 }
 598 #else
 599 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 600                                     int showdefaults)
 601 {
 602 }
 603 #endif
 604
 605 static void nfs_show_nfs_version(struct seq_file *m,
 606                 unsigned int version,
 607                 unsigned int minorversion)
 608 {
 609         seq_printf(m, ",vers=%u", version);
 610         if (version == 4)
 611                 seq_printf(m, ".%u", minorversion);
 612 }
 613
 614 /*
 615  * Describe the mount options in force on this server representation
 616  */
 617 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 618                                    int showdefaults)
 619 {
 620         static const struct proc_nfs_info {
 621                 int flag;
 622                 const char *str;
 623                 const char *nostr;
 624         } nfs_info[] = {
 625                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 626                 { NFS_MOUNT_POSIX, ",posix", "" },
 627                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 628                 { NFS_MOUNT_NOAC, ",noac", "" },
 629                 { NFS_MOUNT_NONLM, ",nolock", "" },
 630                 { NFS_MOUNT_NOACL, ",noacl", "" },
 631                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 632                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 633                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 634                 { 0, NULL, NULL }
 635         };
 636         const struct proc_nfs_info *nfs_infop;
 637         struct nfs_client *clp = nfss->nfs_client;
 638         u32 version = clp->rpc_ops->version;
 639         int local_flock, local_fcntl;
 640
 641         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 642         seq_printf(m, ",rsize=%u", nfss->rsize);
 643         seq_printf(m, ",wsize=%u", nfss->wsize);
 644         if (nfss->bsize != 0)
 645                 seq_printf(m, ",bsize=%u", nfss->bsize);
 646         seq_printf(m, ",namlen=%u", nfss->namelen);
 647         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 648                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 649         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 650                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 651         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 652                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 653         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 654                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 655         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 656                 if (nfss->flags & nfs_infop->flag)
 657                         seq_puts(m, nfs_infop->str);
 658                 else
 659                         seq_puts(m, nfs_infop->nostr);
 660         }
 661         rcu_read_lock();
 662         seq_printf(m, ",proto=%s",
 663                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 664         rcu_read_unlock();
 665         if (version == 4) {
 666                 if (nfss->port != NFS_PORT)
 667                         seq_printf(m, ",port=%u", nfss->port);
 668         } else
 669                 if (nfss->port)
 670                         seq_printf(m, ",port=%u", nfss->port);
 671
 672         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 673         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 674         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 675
 676         if (version != 4)
 677                 nfs_show_mountd_options(m, nfss, showdefaults);
 678         else
 679                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 680
 681         if (nfss->options & NFS_OPTION_FSCACHE)
 682                 seq_printf(m, ",fsc");
 683
 684         if (nfss->options & NFS_OPTION_MIGRATION)
 685                 seq_printf(m, ",migration");
 686
 687         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 688                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 689                         seq_printf(m, ",lookupcache=none");
 690                 else
 691                         seq_printf(m, ",lookupcache=pos");
 692         }
 693
 694         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 695         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 696
 697         if (!local_flock && !local_fcntl)
 698                 seq_printf(m, ",local_lock=none");
 699         else if (local_flock && local_fcntl)
 700                 seq_printf(m, ",local_lock=all");
 701         else if (local_flock)
 702                 seq_printf(m, ",local_lock=flock");
 703         else
 704                 seq_printf(m, ",local_lock=posix");
 705 }
 706
 707 /*
 708  * Describe the mount options on this VFS mountpoint
 709  */
 710 int nfs_show_options(struct seq_file *m, struct dentry *root)
 711 {
 712         struct nfs_server *nfss = NFS_SB(root->d_sb);
 713
 714         nfs_show_mount_options(m, nfss, 0);
 715
 716         rcu_read_lock();
 717         seq_printf(m, ",addr=%s",
 718                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 719                                                         RPC_DISPLAY_ADDR));
 720         rcu_read_unlock();
 721
 722         return 0;
 723 }
 724 EXPORT_SYMBOL_GPL(nfs_show_options);
 725
 726 #if IS_ENABLED(CONFIG_NFS_V4)
 727 #ifdef CONFIG_NFS_V4_1
 728 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 729 {
 730         if (nfs4_has_session(server->nfs_client))
 731                 seq_printf(m, ",sessions");
 732 }
 733 #else
 734 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 735 #endif
 736 #endif
 737
 738 #ifdef CONFIG_NFS_V4_1
 739 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 740 {
 741         seq_printf(m, ",pnfs=");
 742         if (server->pnfs_curr_ld)
 743                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 744         else
 745                 seq_printf(m, "not configured");
 746 }
 747
 748 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 749 {
 750         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 751                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 752                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 753                            "date='%llu,%u'",
 754                            impl_id->name, impl_id->domain,
 755                            impl_id->date.seconds, impl_id->date.nseconds);
 756         }
 757 }
 758 #else
 759 #if IS_ENABLED(CONFIG_NFS_V4)
 760 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 761 {
 762 }
 763 #endif
 764 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 765 {
 766 }
 767 #endif
 768
 769 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 770 {
 771         char *page = (char *) __get_free_page(GFP_KERNEL);
 772         char *devname, *dummy;
 773         int err = 0;
 774         if (!page)
 775                 return -ENOMEM;
 776         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 777         if (IS_ERR(devname))
 778                 err = PTR_ERR(devname);
 779         else
 780                 seq_escape(m, devname, " \t\n\\");
 781         free_page((unsigned long)page);
 782         return err;
 783 }
 784 EXPORT_SYMBOL_GPL(nfs_show_devname);
 785
 786 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 787 {
 788         seq_puts(m, "/");
 789         return 0;
 790 }
 791 EXPORT_SYMBOL_GPL(nfs_show_path);
 792
 793 /*
 794  * Present statistical information for this VFS mountpoint
 795  */
 796 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 797 {
 798         int i, cpu;
 799         struct nfs_server *nfss = NFS_SB(root->d_sb);
 800         struct rpc_auth *auth = nfss->client->cl_auth;
 801         struct nfs_iostats totals = { };
 802
 803         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 804
 805         /*
 806          * Display all mount option settings
 807          */
 808         seq_printf(m, "\n\topts:\t");
 809         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 810         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 811         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 812         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 813         nfs_show_mount_options(m, nfss, 1);
 814
 815         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 816
 817         show_implementation_id(m, nfss);
 818
 819         seq_printf(m, "\n\tcaps:\t");
 820         seq_printf(m, "caps=0x%x", nfss->caps);
 821         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 822         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 823         seq_printf(m, ",bsize=%u", nfss->bsize);
 824         seq_printf(m, ",namlen=%u", nfss->namelen);
 825
 826 #if IS_ENABLED(CONFIG_NFS_V4)
 827         if (nfss->nfs_client->rpc_ops->version == 4) {
 828                 seq_printf(m, "\n\tnfsv4:\t");
 829                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 830                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 831                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 832                 show_sessions(m, nfss);
 833                 show_pnfs(m, nfss);
 834         }
 835 #endif
 836
 837         /*
 838          * Display security flavor in effect for this mount
 839          */
 840         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 841         if (auth->au_flavor)
 842                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 843
 844         /*
 845          * Display superblock I/O counters
 846          */
 847         for_each_possible_cpu(cpu) {
 848                 struct nfs_iostats *stats;
 849
 850                 preempt_disable();
 851                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 852
 853                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 854                         totals.events[i] += stats->events[i];
 855                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 856                         totals.bytes[i] += stats->bytes[i];
 857 #ifdef CONFIG_NFS_FSCACHE
 858                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 859                         totals.fscache[i] += stats->fscache[i];
 860 #endif
 861
 862                 preempt_enable();
 863         }
 864
 865         seq_printf(m, "\n\tevents:\t");
 866         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 867                 seq_printf(m, "%lu ", totals.events[i]);
 868         seq_printf(m, "\n\tbytes:\t");
 869         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 870                 seq_printf(m, "%Lu ", totals.bytes[i]);
 871 #ifdef CONFIG_NFS_FSCACHE
 872         if (nfss->options & NFS_OPTION_FSCACHE) {
 873                 seq_printf(m, "\n\tfsc:\t");
 874                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 875                         seq_printf(m, "%Lu ", totals.bytes[i]);
 876         }
 877 #endif
 878         seq_printf(m, "\n");
 879
 880         rpc_print_iostats(m, nfss->client);
 881
 882         return 0;
 883 }
 884 EXPORT_SYMBOL_GPL(nfs_show_stats);
 885
 886 /*
 887  * Begin unmount by attempting to remove all automounted mountpoints we added
 888  * in response to xdev traversals and referrals
 889  */
 890 void nfs_umount_begin(struct super_block *sb)
 891 {
 892         struct nfs_server *server;
 893         struct rpc_clnt *rpc;
 894
 895         server = NFS_SB(sb);
 896         /* -EIO all pending I/O */
 897         rpc = server->client_acl;
 898         if (!IS_ERR(rpc))
 899                 rpc_killall_tasks(rpc);
 900         rpc = server->client;
 901         if (!IS_ERR(rpc))
 902                 rpc_killall_tasks(rpc);
 903 }
 904 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 905
 906 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 907 {
 908         struct nfs_parsed_mount_data *data;
 909
 910         data = kzalloc(sizeof(*data), GFP_KERNEL);
 911         if (data) {
 912                 data->acregmin          = NFS_DEF_ACREGMIN;
 913                 data->acregmax          = NFS_DEF_ACREGMAX;
 914                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 915                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 916                 data->mount_server.port = NFS_UNSPEC_PORT;
 917                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 918                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 919                 data->auth_flavors[0]   = RPC_AUTH_UNIX;
 920                 data->auth_flavor_len   = 1;
 921                 data->minorversion      = 0;
 922                 data->need_mount        = true;
 923                 data->net               = current->nsproxy->net_ns;
 924                 security_init_mnt_opts(&data->lsm_opts);
 925         }
 926         return data;
 927 }
 928
 929 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 930 {
 931         if (data) {
 932                 kfree(data->client_address);
 933                 kfree(data->mount_server.hostname);
 934                 kfree(data->nfs_server.export_path);
 935                 kfree(data->nfs_server.hostname);
 936                 kfree(data->fscache_uniq);
 937                 security_free_mnt_opts(&data->lsm_opts);
 938                 kfree(data);
 939         }
 940 }
 941
 942 /*
 943  * Sanity-check a server address provided by the mount command.
 944  *
 945  * Address family must be initialized, and address must not be
 946  * the ANY address for that family.
 947  */
 948 static int nfs_verify_server_address(struct sockaddr *addr)
 949 {
 950         switch (addr->sa_family) {
 951         case AF_INET: {
 952                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 953                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 954         }
 955         case AF_INET6: {
 956                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 957                 return !ipv6_addr_any(sa);
 958         }
 959         }
 960
 961         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 962         return 0;
 963 }
 964
 965 /*
 966  * Select between a default port value and a user-specified port value.
 967  * If a zero value is set, then autobind will be used.
 968  */
 969 static void nfs_set_port(struct sockaddr *sap, int *port,
 970                                  const unsigned short default_port)
 971 {
 972         if (*port == NFS_UNSPEC_PORT)
 973                 *port = default_port;
 974
 975         rpc_set_port(sap, *port);
 976 }
 977
 978 /*
 979  * Sanity check the NFS transport protocol.
 980  *
 981  */
 982 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 983 {
 984         switch (mnt->nfs_server.protocol) {
 985         case XPRT_TRANSPORT_UDP:
 986         case XPRT_TRANSPORT_TCP:
 987         case XPRT_TRANSPORT_RDMA:
 988                 break;
 989         default:
 990                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 991         }
 992 }
 993
 994 /*
 995  * For text based NFSv2/v3 mounts, the mount protocol transport default
 996  * settings should depend upon the specified NFS transport.
 997  */
 998 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
 999 {
1000         nfs_validate_transport_protocol(mnt);
1001
1002         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1003             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1004                         return;
1005         switch (mnt->nfs_server.protocol) {
1006         case XPRT_TRANSPORT_UDP:
1007                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1008                 break;
1009         case XPRT_TRANSPORT_TCP:
1010         case XPRT_TRANSPORT_RDMA:
1011                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1012         }
1013 }
1014
1015 /*
1016  * Parse the value of the 'sec=' option.
1017  */
1018 static int nfs_parse_security_flavors(char *value,
1019                                       struct nfs_parsed_mount_data *mnt)
1020 {
1021         substring_t args[MAX_OPT_ARGS];
1022
1023         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1024
1025         switch (match_token(value, nfs_secflavor_tokens, args)) {
1026         case Opt_sec_none:
1027                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1028                 break;
1029         case Opt_sec_sys:
1030                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1031                 break;
1032         case Opt_sec_krb5:
1033                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1034                 break;
1035         case Opt_sec_krb5i:
1036                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1037                 break;
1038         case Opt_sec_krb5p:
1039                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1040                 break;
1041         case Opt_sec_lkey:
1042                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1043                 break;
1044         case Opt_sec_lkeyi:
1045                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1046                 break;
1047         case Opt_sec_lkeyp:
1048                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1049                 break;
1050         case Opt_sec_spkm:
1051                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1052                 break;
1053         case Opt_sec_spkmi:
1054                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1055                 break;
1056         case Opt_sec_spkmp:
1057                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1058                 break;
1059         default:
1060                 return 0;
1061         }
1062
1063         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1064         mnt->auth_flavor_len = 1;
1065         return 1;
1066 }
1067
1068 static int nfs_parse_version_string(char *string,
1069                 struct nfs_parsed_mount_data *mnt,
1070                 substring_t *args)
1071 {
1072         mnt->flags &= ~NFS_MOUNT_VER3;
1073         switch (match_token(string, nfs_vers_tokens, args)) {
1074         case Opt_vers_2:
1075                 mnt->version = 2;
1076                 break;
1077         case Opt_vers_3:
1078                 mnt->flags |= NFS_MOUNT_VER3;
1079                 mnt->version = 3;
1080                 break;
1081         case Opt_vers_4:
1082                 /* Backward compatibility option. In future,
1083                  * the mount program should always supply
1084                  * a NFSv4 minor version number.
1085                  */
1086                 mnt->version = 4;
1087                 break;
1088         case Opt_vers_4_0:
1089                 mnt->version = 4;
1090                 mnt->minorversion = 0;
1091                 break;
1092         case Opt_vers_4_1:
1093                 mnt->version = 4;
1094                 mnt->minorversion = 1;
1095                 break;
1096         default:
1097                 return 0;
1098         }
1099         return 1;
1100 }
1101
1102 static int nfs_get_option_str(substring_t args[], char **option)
1103 {
1104         kfree(*option);
1105         *option = match_strdup(args);
1106         return !*option;
1107 }
1108
1109 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1110 {
1111         int rc;
1112         char *string;
1113
1114         string = match_strdup(args);
1115         if (string == NULL)
1116                 return -ENOMEM;
1117         rc = kstrtoul(string, 10, option);
1118         kfree(string);
1119
1120         return rc;
1121 }
1122
1123 /*
1124  * Error-check and convert a string of mount options from user space into
1125  * a data structure.  The whole mount string is processed; bad options are
1126  * skipped as they are encountered.  If there were no errors, return 1;
1127  * otherwise return 0 (zero).
1128  */
1129 static int nfs_parse_mount_options(char *raw,
1130                                    struct nfs_parsed_mount_data *mnt)
1131 {
1132         char *p, *string, *secdata;
1133         int rc, sloppy = 0, invalid_option = 0;
1134         unsigned short protofamily = AF_UNSPEC;
1135         unsigned short mountfamily = AF_UNSPEC;
1136
1137         if (!raw) {
1138                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1139                 return 1;
1140         }
1141         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1142
1143         secdata = alloc_secdata();
1144         if (!secdata)
1145                 goto out_nomem;
1146
1147         rc = security_sb_copy_data(raw, secdata);
1148         if (rc)
1149                 goto out_security_failure;
1150
1151         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1152         if (rc)
1153                 goto out_security_failure;
1154
1155         free_secdata(secdata);
1156
1157         while ((p = strsep(&raw, ",")) != NULL) {
1158                 substring_t args[MAX_OPT_ARGS];
1159                 unsigned long option;
1160                 int token;
1161
1162                 if (!*p)
1163                         continue;
1164
1165                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1166
1167                 token = match_token(p, nfs_mount_option_tokens, args);
1168                 switch (token) {
1169
1170                 /*
1171                  * boolean options:  foo/nofoo
1172                  */
1173                 case Opt_soft:
1174                         mnt->flags |= NFS_MOUNT_SOFT;
1175                         break;
1176                 case Opt_hard:
1177                         mnt->flags &= ~NFS_MOUNT_SOFT;
1178                         break;
1179                 case Opt_posix:
1180                         mnt->flags |= NFS_MOUNT_POSIX;
1181                         break;
1182                 case Opt_noposix:
1183                         mnt->flags &= ~NFS_MOUNT_POSIX;
1184                         break;
1185                 case Opt_cto:
1186                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1187                         break;
1188                 case Opt_nocto:
1189                         mnt->flags |= NFS_MOUNT_NOCTO;
1190                         break;
1191                 case Opt_ac:
1192                         mnt->flags &= ~NFS_MOUNT_NOAC;
1193                         break;
1194                 case Opt_noac:
1195                         mnt->flags |= NFS_MOUNT_NOAC;
1196                         break;
1197                 case Opt_lock:
1198                         mnt->flags &= ~NFS_MOUNT_NONLM;
1199                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1200                                         NFS_MOUNT_LOCAL_FCNTL);
1201                         break;
1202                 case Opt_nolock:
1203                         mnt->flags |= NFS_MOUNT_NONLM;
1204                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1205                                        NFS_MOUNT_LOCAL_FCNTL);
1206                         break;
1207                 case Opt_udp:
1208                         mnt->flags &= ~NFS_MOUNT_TCP;
1209                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1210                         break;
1211                 case Opt_tcp:
1212                         mnt->flags |= NFS_MOUNT_TCP;
1213                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1214                         break;
1215                 case Opt_rdma:
1216                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1217                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1218                         xprt_load_transport(p);
1219                         break;
1220                 case Opt_acl:
1221                         mnt->flags &= ~NFS_MOUNT_NOACL;
1222                         break;
1223                 case Opt_noacl:
1224                         mnt->flags |= NFS_MOUNT_NOACL;
1225                         break;
1226                 case Opt_rdirplus:
1227                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1228                         break;
1229                 case Opt_nordirplus:
1230                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1231                         break;
1232                 case Opt_sharecache:
1233                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1234                         break;
1235                 case Opt_nosharecache:
1236                         mnt->flags |= NFS_MOUNT_UNSHARED;
1237                         break;
1238                 case Opt_resvport:
1239                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1240                         break;
1241                 case Opt_noresvport:
1242                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1243                         break;
1244                 case Opt_fscache:
1245                         mnt->options |= NFS_OPTION_FSCACHE;
1246                         kfree(mnt->fscache_uniq);
1247                         mnt->fscache_uniq = NULL;
1248                         break;
1249                 case Opt_nofscache:
1250                         mnt->options &= ~NFS_OPTION_FSCACHE;
1251                         kfree(mnt->fscache_uniq);
1252                         mnt->fscache_uniq = NULL;
1253                         break;
1254                 case Opt_migration:
1255                         mnt->options |= NFS_OPTION_MIGRATION;
1256                         break;
1257                 case Opt_nomigration:
1258                         mnt->options &= NFS_OPTION_MIGRATION;
1259                         break;
1260
1261                 /*
1262                  * options that take numeric values
1263                  */
1264                 case Opt_port:
1265                         if (nfs_get_option_ul(args, &option) ||
1266                             option > USHRT_MAX)
1267                                 goto out_invalid_value;
1268                         mnt->nfs_server.port = option;
1269                         break;
1270                 case Opt_rsize:
1271                         if (nfs_get_option_ul(args, &option))
1272                                 goto out_invalid_value;
1273                         mnt->rsize = option;
1274                         break;
1275                 case Opt_wsize:
1276                         if (nfs_get_option_ul(args, &option))
1277                                 goto out_invalid_value;
1278                         mnt->wsize = option;
1279                         break;
1280                 case Opt_bsize:
1281                         if (nfs_get_option_ul(args, &option))
1282                                 goto out_invalid_value;
1283                         mnt->bsize = option;
1284                         break;
1285                 case Opt_timeo:
1286                         if (nfs_get_option_ul(args, &option) || option == 0)
1287                                 goto out_invalid_value;
1288                         mnt->timeo = option;
1289                         break;
1290                 case Opt_retrans:
1291                         if (nfs_get_option_ul(args, &option) || option == 0)
1292                                 goto out_invalid_value;
1293                         mnt->retrans = option;
1294                         break;
1295                 case Opt_acregmin:
1296                         if (nfs_get_option_ul(args, &option))
1297                                 goto out_invalid_value;
1298                         mnt->acregmin = option;
1299                         break;
1300                 case Opt_acregmax:
1301                         if (nfs_get_option_ul(args, &option))
1302                                 goto out_invalid_value;
1303                         mnt->acregmax = option;
1304                         break;
1305                 case Opt_acdirmin:
1306                         if (nfs_get_option_ul(args, &option))
1307                                 goto out_invalid_value;
1308                         mnt->acdirmin = option;
1309                         break;
1310                 case Opt_acdirmax:
1311                         if (nfs_get_option_ul(args, &option))
1312                                 goto out_invalid_value;
1313                         mnt->acdirmax = option;
1314                         break;
1315                 case Opt_actimeo:
1316                         if (nfs_get_option_ul(args, &option))
1317                                 goto out_invalid_value;
1318                         mnt->acregmin = mnt->acregmax =
1319                         mnt->acdirmin = mnt->acdirmax = option;
1320                         break;
1321                 case Opt_namelen:
1322                         if (nfs_get_option_ul(args, &option))
1323                                 goto out_invalid_value;
1324                         mnt->namlen = option;
1325                         break;
1326                 case Opt_mountport:
1327                         if (nfs_get_option_ul(args, &option) ||
1328                             option > USHRT_MAX)
1329                                 goto out_invalid_value;
1330                         mnt->mount_server.port = option;
1331                         break;
1332                 case Opt_mountvers:
1333                         if (nfs_get_option_ul(args, &option) ||
1334                             option < NFS_MNT_VERSION ||
1335                             option > NFS_MNT3_VERSION)
1336                                 goto out_invalid_value;
1337                         mnt->mount_server.version = option;
1338                         break;
1339                 case Opt_minorversion:
1340                         if (nfs_get_option_ul(args, &option))
1341                                 goto out_invalid_value;
1342                         if (option > NFS4_MAX_MINOR_VERSION)
1343                                 goto out_invalid_value;
1344                         mnt->minorversion = option;
1345                         break;
1346
1347                 /*
1348                  * options that take text values
1349                  */
1350                 case Opt_nfsvers:
1351                         string = match_strdup(args);
1352                         if (string == NULL)
1353                                 goto out_nomem;
1354                         rc = nfs_parse_version_string(string, mnt, args);
1355                         kfree(string);
1356                         if (!rc)
1357                                 goto out_invalid_value;
1358                         break;
1359                 case Opt_sec:
1360                         string = match_strdup(args);
1361                         if (string == NULL)
1362                                 goto out_nomem;
1363                         rc = nfs_parse_security_flavors(string, mnt);
1364                         kfree(string);
1365                         if (!rc) {
1366                                 dfprintk(MOUNT, "NFS:   unrecognized "
1367                                                 "security flavor\n");
1368                                 return 0;
1369                         }
1370                         break;
1371                 case Opt_proto:
1372                         string = match_strdup(args);
1373                         if (string == NULL)
1374                                 goto out_nomem;
1375                         token = match_token(string,
1376                                             nfs_xprt_protocol_tokens, args);
1377
1378                         protofamily = AF_INET;
1379                         switch (token) {
1380                         case Opt_xprt_udp6:
1381                                 protofamily = AF_INET6;
1382                         case Opt_xprt_udp:
1383                                 mnt->flags &= ~NFS_MOUNT_TCP;
1384                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1385                                 break;
1386                         case Opt_xprt_tcp6:
1387                                 protofamily = AF_INET6;
1388                         case Opt_xprt_tcp:
1389                                 mnt->flags |= NFS_MOUNT_TCP;
1390                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1391                                 break;
1392                         case Opt_xprt_rdma:
1393                                 /* vector side protocols to TCP */
1394                                 mnt->flags |= NFS_MOUNT_TCP;
1395                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1396                                 xprt_load_transport(string);
1397                                 break;
1398                         default:
1399                                 dfprintk(MOUNT, "NFS:   unrecognized "
1400                                                 "transport protocol\n");
1401                                 kfree(string);
1402                                 return 0;
1403                         }
1404                         kfree(string);
1405                         break;
1406                 case Opt_mountproto:
1407                         string = match_strdup(args);
1408                         if (string == NULL)
1409                                 goto out_nomem;
1410                         token = match_token(string,
1411                                             nfs_xprt_protocol_tokens, args);
1412                         kfree(string);
1413
1414                         mountfamily = AF_INET;
1415                         switch (token) {
1416                         case Opt_xprt_udp6:
1417                                 mountfamily = AF_INET6;
1418                         case Opt_xprt_udp:
1419                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1420                                 break;
1421                         case Opt_xprt_tcp6:
1422                                 mountfamily = AF_INET6;
1423                         case Opt_xprt_tcp:
1424                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1425                                 break;
1426                         case Opt_xprt_rdma: /* not used for side protocols */
1427                         default:
1428                                 dfprintk(MOUNT, "NFS:   unrecognized "
1429                                                 "transport protocol\n");
1430                                 return 0;
1431                         }
1432                         break;
1433                 case Opt_addr:
1434                         string = match_strdup(args);
1435                         if (string == NULL)
1436                                 goto out_nomem;
1437                         mnt->nfs_server.addrlen =
1438                                 rpc_pton(mnt->net, string, strlen(string),
1439                                         (struct sockaddr *)
1440                                         &mnt->nfs_server.address,
1441                                         sizeof(mnt->nfs_server.address));
1442                         kfree(string);
1443                         if (mnt->nfs_server.addrlen == 0)
1444                                 goto out_invalid_address;
1445                         break;
1446                 case Opt_clientaddr:
1447                         if (nfs_get_option_str(args, &mnt->client_address))
1448                                 goto out_nomem;
1449                         break;
1450                 case Opt_mounthost:
1451                         if (nfs_get_option_str(args,
1452                                                &mnt->mount_server.hostname))
1453                                 goto out_nomem;
1454                         break;
1455                 case Opt_mountaddr:
1456                         string = match_strdup(args);
1457                         if (string == NULL)
1458                                 goto out_nomem;
1459                         mnt->mount_server.addrlen =
1460                                 rpc_pton(mnt->net, string, strlen(string),
1461                                         (struct sockaddr *)
1462                                         &mnt->mount_server.address,
1463                                         sizeof(mnt->mount_server.address));
1464                         kfree(string);
1465                         if (mnt->mount_server.addrlen == 0)
1466                                 goto out_invalid_address;
1467                         break;
1468                 case Opt_lookupcache:
1469                         string = match_strdup(args);
1470                         if (string == NULL)
1471                                 goto out_nomem;
1472                         token = match_token(string,
1473                                         nfs_lookupcache_tokens, args);
1474                         kfree(string);
1475                         switch (token) {
1476                                 case Opt_lookupcache_all:
1477                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1478                                         break;
1479                                 case Opt_lookupcache_positive:
1480                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1481                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1482                                         break;
1483                                 case Opt_lookupcache_none:
1484                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1485                                         break;
1486                                 default:
1487                                         dfprintk(MOUNT, "NFS:   invalid "
1488                                                         "lookupcache argument\n");
1489                                         return 0;
1490                         };
1491                         break;
1492                 case Opt_fscache_uniq:
1493                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1494                                 goto out_nomem;
1495                         mnt->options |= NFS_OPTION_FSCACHE;
1496                         break;
1497                 case Opt_local_lock:
1498                         string = match_strdup(args);
1499                         if (string == NULL)
1500                                 goto out_nomem;
1501                         token = match_token(string, nfs_local_lock_tokens,
1502                                         args);
1503                         kfree(string);
1504                         switch (token) {
1505                         case Opt_local_lock_all:
1506                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1507                                                NFS_MOUNT_LOCAL_FCNTL);
1508                                 break;
1509                         case Opt_local_lock_flock:
1510                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1511                                 break;
1512                         case Opt_local_lock_posix:
1513                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1514                                 break;
1515                         case Opt_local_lock_none:
1516                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1517                                                 NFS_MOUNT_LOCAL_FCNTL);
1518                                 break;
1519                         default:
1520                                 dfprintk(MOUNT, "NFS:   invalid "
1521                                                 "local_lock argument\n");
1522                                 return 0;
1523                         };
1524                         break;
1525
1526                 /*
1527                  * Special options
1528                  */
1529                 case Opt_sloppy:
1530                         sloppy = 1;
1531                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1532                         break;
1533                 case Opt_userspace:
1534                 case Opt_deprecated:
1535                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1536                                         "'%s'\n", p);
1537                         break;
1538
1539                 default:
1540                         invalid_option = 1;
1541                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1542                                         "'%s'\n", p);
1543                 }
1544         }
1545
1546         if (!sloppy && invalid_option)
1547                 return 0;
1548
1549         if (mnt->minorversion && mnt->version != 4)
1550                 goto out_minorversion_mismatch;
1551
1552         if (mnt->options & NFS_OPTION_MIGRATION &&
1553             mnt->version != 4 && mnt->minorversion != 0)
1554                 goto out_migration_misuse;
1555
1556         /*
1557          * verify that any proto=/mountproto= options match the address
1558          * families in the addr=/mountaddr= options.
1559          */
1560         if (protofamily != AF_UNSPEC &&
1561             protofamily != mnt->nfs_server.address.ss_family)
1562                 goto out_proto_mismatch;
1563
1564         if (mountfamily != AF_UNSPEC) {
1565                 if (mnt->mount_server.addrlen) {
1566                         if (mountfamily != mnt->mount_server.address.ss_family)
1567                                 goto out_mountproto_mismatch;
1568                 } else {
1569                         if (mountfamily != mnt->nfs_server.address.ss_family)
1570                                 goto out_mountproto_mismatch;
1571                 }
1572         }
1573
1574         return 1;
1575
1576 out_mountproto_mismatch:
1577         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1578                          "option\n");
1579         return 0;
1580 out_proto_mismatch:
1581         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1582         return 0;
1583 out_invalid_address:
1584         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1585         return 0;
1586 out_invalid_value:
1587         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1588         return 0;
1589 out_minorversion_mismatch:
1590         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1591                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1592         return 0;
1593 out_migration_misuse:
1594         printk(KERN_INFO
1595                 "NFS: 'migration' not supported for this NFS version\n");
1596         return 0;
1597 out_nomem:
1598         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1599         return 0;
1600 out_security_failure:
1601         free_secdata(secdata);
1602         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1603         return 0;
1604 }
1605
1606 /*
1607  * Match the requested auth flavors with the list returned by
1608  * the server.  Returns zero and sets the mount's authentication
1609  * flavor on success; returns -EACCES if server does not support
1610  * the requested flavor.
1611  */
1612 static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1613                              struct nfs_mount_request *request)
1614 {
1615         unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1616
1617         /*
1618          * Certain releases of Linux's mountd return an empty
1619          * flavor list.  To prevent behavioral regression with
1620          * these servers (ie. rejecting mounts that used to
1621          * succeed), revert to pre-2.6.32 behavior (no checking)
1622          * if the returned flavor list is empty.
1623          */
1624         if (server_authlist_len == 0)
1625                 return 0;
1626
1627         /*
1628          * We avoid sophisticated negotiating here, as there are
1629          * plenty of cases where we can get it wrong, providing
1630          * either too little or too much security.
1631          *
1632          * RFC 2623, section 2.7 suggests we SHOULD prefer the
1633          * flavor listed first.  However, some servers list
1634          * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1635          * preferred default, in args->auth_flavors[0] if user
1636          * didn't specify sec= mount option.
1637          */
1638         for (i = 0; i < args->auth_flavor_len; i++)
1639                 for (j = 0; j < server_authlist_len; j++)
1640                         if (args->auth_flavors[i] == request->auth_flavs[j]) {
1641                                 dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1642                                         request->auth_flavs[j]);
1643                                 args->auth_flavors[0] = request->auth_flavs[j];
1644                                 return 0;
1645                         }
1646
1647         dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1648         nfs_umount(request);
1649         return -EACCES;
1650 }
1651
1652 /*
1653  * Use the remote server's MOUNT service to request the NFS file handle
1654  * corresponding to the provided path.
1655  */
1656 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1657                              struct nfs_fh *root_fh)
1658 {
1659         rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1660         unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1661         struct nfs_mount_request request = {
1662                 .sap            = (struct sockaddr *)
1663                                                 &args->mount_server.address,
1664                 .dirpath        = args->nfs_server.export_path,
1665                 .protocol       = args->mount_server.protocol,
1666                 .fh             = root_fh,
1667                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1668                 .auth_flav_len  = &server_authlist_len,
1669                 .auth_flavs     = server_authlist,
1670                 .net            = args->net,
1671         };
1672         int status;
1673
1674         if (args->mount_server.version == 0) {
1675                 switch (args->version) {
1676                         default:
1677                                 args->mount_server.version = NFS_MNT3_VERSION;
1678                                 break;
1679                         case 2:
1680                                 args->mount_server.version = NFS_MNT_VERSION;
1681                 }
1682         }
1683         request.version = args->mount_server.version;
1684
1685         if (args->mount_server.hostname)
1686                 request.hostname = args->mount_server.hostname;
1687         else
1688                 request.hostname = args->nfs_server.hostname;
1689
1690         /*
1691          * Construct the mount server's address.
1692          */
1693         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1694                 memcpy(request.sap, &args->nfs_server.address,
1695                        args->nfs_server.addrlen);
1696                 args->mount_server.addrlen = args->nfs_server.addrlen;
1697         }
1698         request.salen = args->mount_server.addrlen;
1699         nfs_set_port(request.sap, &args->mount_server.port, 0);
1700
1701         /*
1702          * Now ask the mount server to map our export path
1703          * to a file handle.
1704          */
1705         status = nfs_mount(&request);
1706         if (status != 0) {
1707                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1708                                 request.hostname, status);
1709                 return status;
1710         }
1711
1712         /*
1713          * MNTv1 (NFSv2) does not support auth flavor negotiation.
1714          */
1715         if (args->mount_server.version != NFS_MNT3_VERSION)
1716                 return 0;
1717         return nfs_walk_authlist(args, &request);
1718 }
1719
1720 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1721                              struct nfs_mount_info *mount_info,
1722                              struct nfs_subversion *nfs_mod)
1723 {
1724         int status;
1725         struct nfs_server *server;
1726
1727         if (mount_info->parsed->need_mount) {
1728                 status = nfs_request_mount(mount_info->parsed, mount_info->mntfh);
1729                 if (status)
1730                         return ERR_PTR(status);
1731         }
1732
1733         /* Get a volume representation */
1734         server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1735         if (IS_ERR(server))
1736                 return ERR_CAST(server);
1737
1738         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1739 }
1740 EXPORT_SYMBOL_GPL(nfs_try_mount);
1741
1742 /*
1743  * Split "dev_name" into "hostname:export_path".
1744  *
1745  * The leftmost colon demarks the split between the server's hostname
1746  * and the export path.  If the hostname starts with a left square
1747  * bracket, then it may contain colons.
1748  *
1749  * Note: caller frees hostname and export path, even on error.
1750  */
1751 static int nfs_parse_devname(const char *dev_name,
1752                              char **hostname, size_t maxnamlen,
1753                              char **export_path, size_t maxpathlen)
1754 {
1755         size_t len;
1756         char *end;
1757
1758         /* Is the host name protected with square brakcets? */
1759         if (*dev_name == '[') {
1760                 end = strchr(++dev_name, ']');
1761                 if (end == NULL || end[1] != ':')
1762                         goto out_bad_devname;
1763
1764                 len = end - dev_name;
1765                 end++;
1766         } else {
1767                 char *comma;
1768
1769                 end = strchr(dev_name, ':');
1770                 if (end == NULL)
1771                         goto out_bad_devname;
1772                 len = end - dev_name;
1773
1774                 /* kill possible hostname list: not supported */
1775                 comma = strchr(dev_name, ',');
1776                 if (comma != NULL && comma < end)
1777                         *comma = 0;
1778         }
1779
1780         if (len > maxnamlen)
1781                 goto out_hostname;
1782
1783         /* N.B. caller will free nfs_server.hostname in all cases */
1784         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1785         if (*hostname == NULL)
1786                 goto out_nomem;
1787         len = strlen(++end);
1788         if (len > maxpathlen)
1789                 goto out_path;
1790         *export_path = kstrndup(end, len, GFP_KERNEL);
1791         if (!*export_path)
1792                 goto out_nomem;
1793
1794         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1795         return 0;
1796
1797 out_bad_devname:
1798         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1799         return -EINVAL;
1800
1801 out_nomem:
1802         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1803         return -ENOMEM;
1804
1805 out_hostname:
1806         dfprintk(MOUNT, "NFS: server hostname too long\n");
1807         return -ENAMETOOLONG;
1808
1809 out_path:
1810         dfprintk(MOUNT, "NFS: export pathname too long\n");
1811         return -ENAMETOOLONG;
1812 }
1813
1814 /*
1815  * Validate the NFS2/NFS3 mount data
1816  * - fills in the mount root filehandle
1817  *
1818  * For option strings, user space handles the following behaviors:
1819  *
1820  * + DNS: mapping server host name to IP address ("addr=" option)
1821  *
1822  * + failure mode: how to behave if a mount request can't be handled
1823  *   immediately ("fg/bg" option)
1824  *
1825  * + retry: how often to retry a mount request ("retry=" option)
1826  *
1827  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1828  *   mountproto=tcp after mountproto=udp, and so on
1829  */
1830 static int nfs23_validate_mount_data(void *options,
1831                                      struct nfs_parsed_mount_data *args,
1832                                      struct nfs_fh *mntfh,
1833                                      const char *dev_name)
1834 {
1835         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1836         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1837
1838         if (data == NULL)
1839                 goto out_no_data;
1840
1841         args->version = NFS_DEFAULT_VERSION;
1842         switch (data->version) {
1843         case 1:
1844                 data->namlen = 0;
1845         case 2:
1846                 data->bsize = 0;
1847         case 3:
1848                 if (data->flags & NFS_MOUNT_VER3)
1849                         goto out_no_v3;
1850                 data->root.size = NFS2_FHSIZE;
1851                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1852         case 4:
1853                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1854                         goto out_no_sec;
1855         case 5:
1856                 memset(data->context, 0, sizeof(data->context));
1857         case 6:
1858                 if (data->flags & NFS_MOUNT_VER3) {
1859                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1860                                 goto out_invalid_fh;
1861                         mntfh->size = data->root.size;
1862                         args->version = 3;
1863                 } else {
1864                         mntfh->size = NFS2_FHSIZE;
1865                         args->version = 2;
1866                 }
1867
1868
1869                 memcpy(mntfh->data, data->root.data, mntfh->size);
1870                 if (mntfh->size < sizeof(mntfh->data))
1871                         memset(mntfh->data + mntfh->size, 0,
1872                                sizeof(mntfh->data) - mntfh->size);
1873
1874                 /*
1875                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1876                  * can deal with.
1877                  */
1878                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1879                 args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1880                 args->rsize             = data->rsize;
1881                 args->wsize             = data->wsize;
1882                 args->timeo             = data->timeo;
1883                 args->retrans           = data->retrans;
1884                 args->acregmin          = data->acregmin;
1885                 args->acregmax          = data->acregmax;
1886                 args->acdirmin          = data->acdirmin;
1887                 args->acdirmax          = data->acdirmax;
1888                 args->need_mount        = false;
1889
1890                 memcpy(sap, &data->addr, sizeof(data->addr));
1891                 args->nfs_server.addrlen = sizeof(data->addr);
1892                 args->nfs_server.port = ntohs(data->addr.sin_port);
1893                 if (!nfs_verify_server_address(sap))
1894                         goto out_no_address;
1895
1896                 if (!(data->flags & NFS_MOUNT_TCP))
1897                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1898                 /* N.B. caller will free nfs_server.hostname in all cases */
1899                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1900                 args->namlen            = data->namlen;
1901                 args->bsize             = data->bsize;
1902
1903                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1904                         args->auth_flavors[0] = data->pseudoflavor;
1905                 if (!args->nfs_server.hostname)
1906                         goto out_nomem;
1907
1908                 if (!(data->flags & NFS_MOUNT_NONLM))
1909                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1910                                          NFS_MOUNT_LOCAL_FCNTL);
1911                 else
1912                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1913                                         NFS_MOUNT_LOCAL_FCNTL);
1914                 /*
1915                  * The legacy version 6 binary mount data from userspace has a
1916                  * field used only to transport selinux information into the
1917                  * the kernel.  To continue to support that functionality we
1918                  * have a touch of selinux knowledge here in the NFS code. The
1919                  * userspace code converted context=blah to just blah so we are
1920                  * converting back to the full string selinux understands.
1921                  */
1922                 if (data->context[0]){
1923 #ifdef CONFIG_SECURITY_SELINUX
1924                         int rc;
1925                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1926                         if (!opts_str)
1927                                 return -ENOMEM;
1928                         strcpy(opts_str, "context=");
1929                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1930                         strcat(opts_str, &data->context[0]);
1931                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1932                         kfree(opts_str);
1933                         if (rc)
1934                                 return rc;
1935 #else
1936                         return -EINVAL;
1937 #endif
1938                 }
1939
1940                 break;
1941         default:
1942                 return NFS_TEXT_DATA;
1943         }
1944
1945 #if !IS_ENABLED(CONFIG_NFS_V3)
1946         if (args->version == 3)
1947                 goto out_v3_not_compiled;
1948 #endif /* !CONFIG_NFS_V3 */
1949
1950         return 0;
1951
1952 out_no_data:
1953         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
1954         return -EINVAL;
1955
1956 out_no_v3:
1957         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
1958                  data->version);
1959         return -EINVAL;
1960
1961 out_no_sec:
1962         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
1963         return -EINVAL;
1964
1965 #if !IS_ENABLED(CONFIG_NFS_V3)
1966 out_v3_not_compiled:
1967         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
1968         return -EPROTONOSUPPORT;
1969 #endif /* !CONFIG_NFS_V3 */
1970
1971 out_nomem:
1972         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
1973         return -ENOMEM;
1974
1975 out_no_address:
1976         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
1977         return -EINVAL;
1978
1979 out_invalid_fh:
1980         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
1981         return -EINVAL;
1982 }
1983
1984 #if IS_ENABLED(CONFIG_NFS_V4)
1985 static int nfs_validate_mount_data(struct file_system_type *fs_type,
1986                                    void *options,
1987                                    struct nfs_parsed_mount_data *args,
1988                                    struct nfs_fh *mntfh,
1989                                    const char *dev_name)
1990 {
1991         if (fs_type == &nfs_fs_type)
1992                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
1993         return nfs4_validate_mount_data(options, args, dev_name);
1994 }
1995 #else
1996 static int nfs_validate_mount_data(struct file_system_type *fs_type,
1997                                    void *options,
1998                                    struct nfs_parsed_mount_data *args,
1999                                    struct nfs_fh *mntfh,
2000                                    const char *dev_name)
2001 {
2002         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2003 }
2004 #endif
2005
2006 static int nfs_validate_text_mount_data(void *options,
2007                                         struct nfs_parsed_mount_data *args,
2008                                         const char *dev_name)
2009 {
2010         int port = 0;
2011         int max_namelen = PAGE_SIZE;
2012         int max_pathlen = NFS_MAXPATHLEN;
2013         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2014
2015         if (nfs_parse_mount_options((char *)options, args) == 0)
2016                 return -EINVAL;
2017
2018         if (!nfs_verify_server_address(sap))
2019                 goto out_no_address;
2020
2021         if (args->version == 4) {
2022 #if IS_ENABLED(CONFIG_NFS_V4)
2023                 port = NFS_PORT;
2024                 max_namelen = NFS4_MAXNAMLEN;
2025                 max_pathlen = NFS4_MAXPATHLEN;
2026                 nfs_validate_transport_protocol(args);
2027                 nfs4_validate_mount_flags(args);
2028 #else
2029                 goto out_v4_not_compiled;
2030 #endif /* CONFIG_NFS_V4 */
2031         } else
2032                 nfs_set_mount_transport_protocol(args);
2033
2034         nfs_set_port(sap, &args->nfs_server.port, port);
2035
2036         if (args->auth_flavor_len > 1)
2037                 goto out_bad_auth;
2038
2039         return nfs_parse_devname(dev_name,
2040                                    &args->nfs_server.hostname,
2041                                    max_namelen,
2042                                    &args->nfs_server.export_path,
2043                                    max_pathlen);
2044
2045 #if !IS_ENABLED(CONFIG_NFS_V4)
2046 out_v4_not_compiled:
2047         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2048         return -EPROTONOSUPPORT;
2049 #endif /* !CONFIG_NFS_V4 */
2050
2051 out_no_address:
2052         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2053         return -EINVAL;
2054
2055 out_bad_auth:
2056         dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
2057         return -EINVAL;
2058 }
2059
2060 static int
2061 nfs_compare_remount_data(struct nfs_server *nfss,
2062                          struct nfs_parsed_mount_data *data)
2063 {
2064         if (data->flags != nfss->flags ||
2065             data->rsize != nfss->rsize ||
2066             data->wsize != nfss->wsize ||
2067             data->retrans != nfss->client->cl_timeout->to_retries ||
2068             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2069             data->acregmin != nfss->acregmin / HZ ||
2070             data->acregmax != nfss->acregmax / HZ ||
2071             data->acdirmin != nfss->acdirmin / HZ ||
2072             data->acdirmax != nfss->acdirmax / HZ ||
2073             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2074             data->nfs_server.port != nfss->port ||
2075             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2076             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2077                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2078                 return -EINVAL;
2079
2080         return 0;
2081 }
2082
2083 int
2084 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2085 {
2086         int error;
2087         struct nfs_server *nfss = sb->s_fs_info;
2088         struct nfs_parsed_mount_data *data;
2089         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2090         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2091         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2092
2093         /*
2094          * Userspace mount programs that send binary options generally send
2095          * them populated with default values. We have no way to know which
2096          * ones were explicitly specified. Fall back to legacy behavior and
2097          * just return success.
2098          */
2099         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2100             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2101                                            options->version <= 6))))
2102                 return 0;
2103
2104         data = kzalloc(sizeof(*data), GFP_KERNEL);
2105         if (data == NULL)
2106                 return -ENOMEM;
2107
2108         /* fill out struct with values from existing mount */
2109         data->flags = nfss->flags;
2110         data->rsize = nfss->rsize;
2111         data->wsize = nfss->wsize;
2112         data->retrans = nfss->client->cl_timeout->to_retries;
2113         data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2114         data->acregmin = nfss->acregmin / HZ;
2115         data->acregmax = nfss->acregmax / HZ;
2116         data->acdirmin = nfss->acdirmin / HZ;
2117         data->acdirmax = nfss->acdirmax / HZ;
2118         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2119         data->nfs_server.port = nfss->port;
2120         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2121         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2122                 data->nfs_server.addrlen);
2123
2124         /* overwrite those values with any that were specified */
2125         error = nfs_parse_mount_options((char *)options, data);
2126         if (error < 0)
2127                 goto out;
2128
2129         /*
2130          * noac is a special case. It implies -o sync, but that's not
2131          * necessarily reflected in the mtab options. do_remount_sb
2132          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2133          * remount options, so we have to explicitly reset it.
2134          */
2135         if (data->flags & NFS_MOUNT_NOAC)
2136                 *flags |= MS_SYNCHRONOUS;
2137
2138         /* compare new mount options with old ones */
2139         error = nfs_compare_remount_data(nfss, data);
2140 out:
2141         kfree(data);
2142         return error;
2143 }
2144 EXPORT_SYMBOL_GPL(nfs_remount);
2145
2146 /*
2147  * Initialise the common bits of the superblock
2148  */
2149 inline void nfs_initialise_sb(struct super_block *sb)
2150 {
2151         struct nfs_server *server = NFS_SB(sb);
2152
2153         sb->s_magic = NFS_SUPER_MAGIC;
2154
2155         /* We probably want something more informative here */
2156         snprintf(sb->s_id, sizeof(sb->s_id),
2157                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2158
2159         if (sb->s_blocksize == 0)
2160                 sb->s_blocksize = nfs_block_bits(server->wsize,
2161                                                  &sb->s_blocksize_bits);
2162
2163         sb->s_bdi = &server->backing_dev_info;
2164
2165         nfs_super_set_maxbytes(sb, server->maxfilesize);
2166 }
2167
2168 /*
2169  * Finish setting up an NFS2/3 superblock
2170  */
2171 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2172 {
2173         struct nfs_parsed_mount_data *data = mount_info->parsed;
2174         struct nfs_server *server = NFS_SB(sb);
2175
2176         sb->s_blocksize_bits = 0;
2177         sb->s_blocksize = 0;
2178         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2179         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2180         if (data && data->bsize)
2181                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2182
2183         if (server->nfs_client->rpc_ops->version != 2) {
2184                 /* The VFS shouldn't apply the umask to mode bits. We will do
2185                  * so ourselves when necessary.
2186                  */
2187                 sb->s_flags |= MS_POSIXACL;
2188                 sb->s_time_gran = 1;
2189         }
2190
2191         nfs_initialise_sb(sb);
2192 }
2193 EXPORT_SYMBOL_GPL(nfs_fill_super);
2194
2195 /*
2196  * Finish setting up a cloned NFS2/3/4 superblock
2197  */
2198 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2199 {
2200         const struct super_block *old_sb = mount_info->cloned->sb;
2201         struct nfs_server *server = NFS_SB(sb);
2202
2203         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2204         sb->s_blocksize = old_sb->s_blocksize;
2205         sb->s_maxbytes = old_sb->s_maxbytes;
2206         sb->s_xattr = old_sb->s_xattr;
2207         sb->s_op = old_sb->s_op;
2208         sb->s_time_gran = 1;
2209
2210         if (server->nfs_client->rpc_ops->version != 2) {
2211                 /* The VFS shouldn't apply the umask to mode bits. We will do
2212                  * so ourselves when necessary.
2213                  */
2214                 sb->s_flags |= MS_POSIXACL;
2215         }
2216
2217         nfs_initialise_sb(sb);
2218 }
2219
2220 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2221 {
2222         const struct nfs_server *a = s->s_fs_info;
2223         const struct rpc_clnt *clnt_a = a->client;
2224         const struct rpc_clnt *clnt_b = b->client;
2225
2226         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2227                 goto Ebusy;
2228         if (a->nfs_client != b->nfs_client)
2229                 goto Ebusy;
2230         if (a->flags != b->flags)
2231                 goto Ebusy;
2232         if (a->wsize != b->wsize)
2233                 goto Ebusy;
2234         if (a->rsize != b->rsize)
2235                 goto Ebusy;
2236         if (a->acregmin != b->acregmin)
2237                 goto Ebusy;
2238         if (a->acregmax != b->acregmax)
2239                 goto Ebusy;
2240         if (a->acdirmin != b->acdirmin)
2241                 goto Ebusy;
2242         if (a->acdirmax != b->acdirmax)
2243                 goto Ebusy;
2244         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2245                 goto Ebusy;
2246         return 1;
2247 Ebusy:
2248         return 0;
2249 }
2250
2251 struct nfs_sb_mountdata {
2252         struct nfs_server *server;
2253         int mntflags;
2254 };
2255
2256 static int nfs_set_super(struct super_block *s, void *data)
2257 {
2258         struct nfs_sb_mountdata *sb_mntdata = data;
2259         struct nfs_server *server = sb_mntdata->server;
2260         int ret;
2261
2262         s->s_flags = sb_mntdata->mntflags;
2263         s->s_fs_info = server;
2264         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2265         ret = set_anon_super(s, server);
2266         if (ret == 0)
2267                 server->s_dev = s->s_dev;
2268         return ret;
2269 }
2270
2271 static int nfs_compare_super_address(struct nfs_server *server1,
2272                                      struct nfs_server *server2)
2273 {
2274         struct sockaddr *sap1, *sap2;
2275
2276         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2277         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2278
2279         if (sap1->sa_family != sap2->sa_family)
2280                 return 0;
2281
2282         switch (sap1->sa_family) {
2283         case AF_INET: {
2284                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2285                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2286                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2287                         return 0;
2288                 if (sin1->sin_port != sin2->sin_port)
2289                         return 0;
2290                 break;
2291         }
2292         case AF_INET6: {
2293                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2294                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2295                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2296                         return 0;
2297                 if (sin1->sin6_port != sin2->sin6_port)
2298                         return 0;
2299                 break;
2300         }
2301         default:
2302                 return 0;
2303         }
2304
2305         return 1;
2306 }
2307
2308 static int nfs_compare_super(struct super_block *sb, void *data)
2309 {
2310         struct nfs_sb_mountdata *sb_mntdata = data;
2311         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2312         int mntflags = sb_mntdata->mntflags;
2313
2314         if (!nfs_compare_super_address(old, server))
2315                 return 0;
2316         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2317         if (old->flags & NFS_MOUNT_UNSHARED)
2318                 return 0;
2319         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2320                 return 0;
2321         return nfs_compare_mount_options(sb, server, mntflags);
2322 }
2323
2324 #ifdef CONFIG_NFS_FSCACHE
2325 static void nfs_get_cache_cookie(struct super_block *sb,
2326                                  struct nfs_parsed_mount_data *parsed,
2327                                  struct nfs_clone_mount *cloned)
2328 {
2329         struct nfs_server *nfss = NFS_SB(sb);
2330         char *uniq = NULL;
2331         int ulen = 0;
2332
2333         nfss->fscache_key = NULL;
2334         nfss->fscache = NULL;
2335
2336         if (parsed) {
2337                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2338                         return;
2339                 if (parsed->fscache_uniq) {
2340                         uniq = parsed->fscache_uniq;
2341                         ulen = strlen(parsed->fscache_uniq);
2342                 }
2343         } else if (cloned) {
2344                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2345                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2346                         return;
2347                 if (mnt_s->fscache_key) {
2348                         uniq = mnt_s->fscache_key->key.uniquifier;
2349                         ulen = mnt_s->fscache_key->key.uniq_len;
2350                 };
2351         } else
2352                 return;
2353
2354         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2355 }
2356 #else
2357 static void nfs_get_cache_cookie(struct super_block *sb,
2358                                  struct nfs_parsed_mount_data *parsed,
2359                                  struct nfs_clone_mount *cloned)
2360 {
2361 }
2362 #endif
2363
2364 static int nfs_bdi_register(struct nfs_server *server)
2365 {
2366         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2367 }
2368
2369 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2370                         struct nfs_mount_info *mount_info)
2371 {
2372         return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts);
2373 }
2374 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2375
2376 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2377                           struct nfs_mount_info *mount_info)
2378 {
2379         /* clone any lsm security options from the parent to the new sb */
2380         security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2381         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2382                 return -ESTALE;
2383         return 0;
2384 }
2385 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2386
2387 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2388                                    int flags, const char *dev_name,
2389                                    struct nfs_mount_info *mount_info,
2390                                    struct nfs_subversion *nfs_mod)
2391 {
2392         struct super_block *s;
2393         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2394         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2395         struct nfs_sb_mountdata sb_mntdata = {
2396                 .mntflags = flags,
2397                 .server = server,
2398         };
2399         int error;
2400
2401         if (server->flags & NFS_MOUNT_UNSHARED)
2402                 compare_super = NULL;
2403
2404         /* -o noac implies -o sync */
2405         if (server->flags & NFS_MOUNT_NOAC)
2406                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2407
2408         /* Get a superblock - note that we may end up sharing one that already exists */
2409         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2410         if (IS_ERR(s)) {
2411                 mntroot = ERR_CAST(s);
2412                 goto out_err_nosb;
2413         }
2414
2415         if (s->s_fs_info != server) {
2416                 nfs_free_server(server);
2417                 server = NULL;
2418         } else {
2419                 error = nfs_bdi_register(server);
2420                 if (error) {
2421                         mntroot = ERR_PTR(error);
2422                         goto error_splat_bdi;
2423                 }
2424         }
2425
2426         if (!s->s_root) {
2427                 /* initial superblock/root creation */
2428                 mount_info->fill_super(s, mount_info);
2429                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2430         }
2431
2432         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2433         if (IS_ERR(mntroot))
2434                 goto error_splat_super;
2435
2436         error = mount_info->set_security(s, mntroot, mount_info);
2437         if (error)
2438                 goto error_splat_root;
2439
2440         s->s_flags |= MS_ACTIVE;
2441
2442 out:
2443         return mntroot;
2444
2445 out_err_nosb:
2446         nfs_free_server(server);
2447         goto out;
2448
2449 error_splat_root:
2450         dput(mntroot);
2451         mntroot = ERR_PTR(error);
2452 error_splat_super:
2453         if (server && !s->s_root)
2454                 bdi_unregister(&server->backing_dev_info);
2455 error_splat_bdi:
2456         deactivate_locked_super(s);
2457         goto out;
2458 }
2459 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2460
2461 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2462         int flags, const char *dev_name, void *raw_data)
2463 {
2464         struct nfs_mount_info mount_info = {
2465                 .fill_super = nfs_fill_super,
2466                 .set_security = nfs_set_sb_security,
2467         };
2468         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2469         struct nfs_subversion *nfs_mod;
2470         int error;
2471
2472         mount_info.parsed = nfs_alloc_parsed_mount_data();
2473         mount_info.mntfh = nfs_alloc_fhandle();
2474         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2475                 goto out;
2476
2477         /* Validate the mount data */
2478         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2479         if (error == NFS_TEXT_DATA)
2480                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2481         if (error < 0) {
2482                 mntroot = ERR_PTR(error);
2483                 goto out;
2484         }
2485
2486         nfs_mod = get_nfs_version(mount_info.parsed->version);
2487         if (IS_ERR(nfs_mod)) {
2488                 mntroot = ERR_CAST(nfs_mod);
2489                 goto out;
2490         }
2491
2492         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2493
2494         put_nfs_version(nfs_mod);
2495 out:
2496         nfs_free_parsed_mount_data(mount_info.parsed);
2497         nfs_free_fhandle(mount_info.mntfh);
2498         return mntroot;
2499 }
2500 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2501
2502 /*
2503  * Ensure that we unregister the bdi before kill_anon_super
2504  * releases the device name
2505  */
2506 void nfs_put_super(struct super_block *s)
2507 {
2508         struct nfs_server *server = NFS_SB(s);
2509
2510         bdi_unregister(&server->backing_dev_info);
2511 }
2512 EXPORT_SYMBOL_GPL(nfs_put_super);
2513
2514 /*
2515  * Destroy an NFS2/3 superblock
2516  */
2517 void nfs_kill_super(struct super_block *s)
2518 {
2519         struct nfs_server *server = NFS_SB(s);
2520
2521         kill_anon_super(s);
2522         nfs_fscache_release_super_cookie(s);
2523         nfs_free_server(server);
2524 }
2525 EXPORT_SYMBOL_GPL(nfs_kill_super);
2526
2527 /*
2528  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2529  */
2530 static struct dentry *
2531 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2532                 const char *dev_name, void *raw_data)
2533 {
2534         struct nfs_clone_mount *data = raw_data;
2535         struct nfs_mount_info mount_info = {
2536                 .fill_super = nfs_clone_super,
2537                 .set_security = nfs_clone_sb_security,
2538                 .cloned = data,
2539         };
2540         struct nfs_server *server;
2541         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2542         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2543
2544         dprintk("--> nfs_xdev_mount()\n");
2545
2546         mount_info.mntfh = mount_info.cloned->fh;
2547
2548         /* create a new volume representation */
2549         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2550
2551         if (IS_ERR(server))
2552                 mntroot = ERR_CAST(server);
2553         else
2554                 mntroot = nfs_fs_mount_common(server, flags,
2555                                 dev_name, &mount_info, nfs_mod);
2556
2557         dprintk("<-- nfs_xdev_mount() = %ld\n",
2558                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2559         return mntroot;
2560 }
2561
2562 #if IS_ENABLED(CONFIG_NFS_V4)
2563
2564 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2565 {
2566         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2567                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2568 }
2569
2570 /*
2571  * Validate NFSv4 mount options
2572  */
2573 static int nfs4_validate_mount_data(void *options,
2574                                     struct nfs_parsed_mount_data *args,
2575                                     const char *dev_name)
2576 {
2577         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2578         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2579         char *c;
2580
2581         if (data == NULL)
2582                 goto out_no_data;
2583
2584         args->version = 4;
2585
2586         switch (data->version) {
2587         case 1:
2588                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2589                         goto out_no_address;
2590                 if (data->host_addrlen == 0)
2591                         goto out_no_address;
2592                 args->nfs_server.addrlen = data->host_addrlen;
2593                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2594                         return -EFAULT;
2595                 if (!nfs_verify_server_address(sap))
2596                         goto out_no_address;
2597                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2598
2599                 if (data->auth_flavourlen) {
2600                         if (data->auth_flavourlen > 1)
2601                                 goto out_inval_auth;
2602                         if (copy_from_user(&args->auth_flavors[0],
2603                                            data->auth_flavours,
2604                                            sizeof(args->auth_flavors[0])))
2605                                 return -EFAULT;
2606                 }
2607
2608                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2609                 if (IS_ERR(c))
2610                         return PTR_ERR(c);
2611                 args->nfs_server.hostname = c;
2612
2613                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2614                 if (IS_ERR(c))
2615                         return PTR_ERR(c);
2616                 args->nfs_server.export_path = c;
2617                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2618
2619                 c = strndup_user(data->client_addr.data, 16);
2620                 if (IS_ERR(c))
2621                         return PTR_ERR(c);
2622                 args->client_address = c;
2623
2624                 /*
2625                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2626                  * can deal with.
2627                  */
2628
2629                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2630                 args->rsize     = data->rsize;
2631                 args->wsize     = data->wsize;
2632                 args->timeo     = data->timeo;
2633                 args->retrans   = data->retrans;
2634                 args->acregmin  = data->acregmin;
2635                 args->acregmax  = data->acregmax;
2636                 args->acdirmin  = data->acdirmin;
2637                 args->acdirmax  = data->acdirmax;
2638                 args->nfs_server.protocol = data->proto;
2639                 nfs_validate_transport_protocol(args);
2640
2641                 break;
2642         default:
2643                 return NFS_TEXT_DATA;
2644         }
2645
2646         return 0;
2647
2648 out_no_data:
2649         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2650         return -EINVAL;
2651
2652 out_inval_auth:
2653         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2654                  data->auth_flavourlen);
2655         return -EINVAL;
2656
2657 out_no_address:
2658         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2659         return -EINVAL;
2660 }
2661
2662 /*
2663  * NFS v4 module parameters need to stay in the
2664  * NFS client for backwards compatibility
2665  */
2666 unsigned int nfs_callback_set_tcpport;
2667 unsigned short nfs_callback_tcpport;
2668 /* Default cache timeout is 10 minutes */
2669 unsigned int nfs_idmap_cache_timeout = 600;
2670 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2671 bool nfs4_disable_idmapping = true;
2672 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2673 unsigned short send_implementation_id = 1;
2674 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2675
2676 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2677 EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2678 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2679 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2680 EXPORT_SYMBOL_GPL(max_session_slots);
2681 EXPORT_SYMBOL_GPL(send_implementation_id);
2682 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2683
2684 #define NFS_CALLBACK_MAXPORTNR (65535U)
2685
2686 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2687 {
2688         unsigned long num;
2689         int ret;
2690
2691         if (!val)
2692                 return -EINVAL;
2693         ret = kstrtoul(val, 0, &num);
2694         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2695                 return -EINVAL;
2696         *((unsigned int *)kp->arg) = num;
2697         return 0;
2698 }
2699 static struct kernel_param_ops param_ops_portnr = {
2700         .set = param_set_portnr,
2701         .get = param_get_uint,
2702 };
2703 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2704
2705 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2706 module_param(nfs_idmap_cache_timeout, int, 0644);
2707 module_param(nfs4_disable_idmapping, bool, 0644);
2708 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2709                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2710 MODULE_PARM_DESC(nfs4_disable_idmapping,
2711                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2712 module_param(max_session_slots, ushort, 0644);
2713 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2714                 "requests the client will negotiate");
2715 module_param(send_implementation_id, ushort, 0644);
2716 MODULE_PARM_DESC(send_implementation_id,
2717                 "Send implementation ID with NFSv4.1 exchange_id");
2718 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2719 MODULE_ALIAS("nfs4");
2720
2721 #endif /* CONFIG_NFS_V4 */