fs/nfs/super.c

   1 /*
   2  *  linux/fs/nfs/super.c
   3  *
   4  *  Copyright (C) 1992  Rick Sladkey
   5  *
   6  *  nfs superblock handling functions
   7  *
   8  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
   9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
  10  *
  11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
  12  *  J.S.Peatfield@damtp.cam.ac.uk
  13  *
  14  *  Split from inode.c by David Howells <dhowells@redhat.com>
  15  *
  16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
  17  *   particular server are held in the same superblock
  18  * - NFS superblocks can have several effective roots to the dentry tree
  19  * - directory type roots are spliced into the tree when a path from one root reaches the root
  20  *   of another (see nfs_lookup())
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/init.h>
  25
  26 #include <linux/time.h>
  27 #include <linux/kernel.h>
  28 #include <linux/mm.h>
  29 #include <linux/string.h>
  30 #include <linux/stat.h>
  31 #include <linux/errno.h>
  32 #include <linux/unistd.h>
  33 #include <linux/sunrpc/clnt.h>
  34 #include <linux/sunrpc/addr.h>
  35 #include <linux/sunrpc/stats.h>
  36 #include <linux/sunrpc/metrics.h>
  37 #include <linux/sunrpc/xprtsock.h>
  38 #include <linux/sunrpc/xprtrdma.h>
  39 #include <linux/nfs_fs.h>
  40 #include <linux/nfs_mount.h>
  41 #include <linux/nfs4_mount.h>
  42 #include <linux/lockd/bind.h>
  43 #include <linux/seq_file.h>
  44 #include <linux/mount.h>
  45 #include <linux/namei.h>
  46 #include <linux/nfs_idmap.h>
  47 #include <linux/vfs.h>
  48 #include <linux/inet.h>
  49 #include <linux/in6.h>
  50 #include <linux/slab.h>
  51 #include <net/ipv6.h>
  52 #include <linux/netdevice.h>
  53 #include <linux/nfs_xdr.h>
  54 #include <linux/magic.h>
  55 #include <linux/parser.h>
  56 #include <linux/nsproxy.h>
  57 #include <linux/rcupdate.h>
  58
  59 #include <asm/uaccess.h>
  60
  61 #include "nfs4_fs.h"
  62 #include "callback.h"
  63 #include "delegation.h"
  64 #include "iostat.h"
  65 #include "internal.h"
  66 #include "fscache.h"
  67 #include "nfs4session.h"
  68 #include "pnfs.h"
  69 #include "nfs.h"
  70
  71 #define NFSDBG_FACILITY         NFSDBG_VFS
  72 #define NFS_TEXT_DATA           1
  73
  74 #if IS_ENABLED(CONFIG_NFS_V3)
  75 #define NFS_DEFAULT_VERSION 3
  76 #else
  77 #define NFS_DEFAULT_VERSION 2
  78 #endif
  79
  80 enum {
  81         /* Mount options that take no arguments */
  82         Opt_soft, Opt_hard,
  83         Opt_posix, Opt_noposix,
  84         Opt_cto, Opt_nocto,
  85         Opt_ac, Opt_noac,
  86         Opt_lock, Opt_nolock,
  87         Opt_udp, Opt_tcp, Opt_rdma,
  88         Opt_acl, Opt_noacl,
  89         Opt_rdirplus, Opt_nordirplus,
  90         Opt_sharecache, Opt_nosharecache,
  91         Opt_resvport, Opt_noresvport,
  92         Opt_fscache, Opt_nofscache,
  93         Opt_migration, Opt_nomigration,
  94
  95         /* Mount options that take integer arguments */
  96         Opt_port,
  97         Opt_rsize, Opt_wsize, Opt_bsize,
  98         Opt_timeo, Opt_retrans,
  99         Opt_acregmin, Opt_acregmax,
 100         Opt_acdirmin, Opt_acdirmax,
 101         Opt_actimeo,
 102         Opt_namelen,
 103         Opt_mountport,
 104         Opt_mountvers,
 105         Opt_minorversion,
 106
 107         /* Mount options that take string arguments */
 108         Opt_nfsvers,
 109         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 110         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 111         Opt_lookupcache,
 112         Opt_fscache_uniq,
 113         Opt_local_lock,
 114
 115         /* Special mount options */
 116         Opt_userspace, Opt_deprecated, Opt_sloppy,
 117
 118         Opt_err
 119 };
 120
 121 static const match_table_t nfs_mount_option_tokens = {
 122         { Opt_userspace, "bg" },
 123         { Opt_userspace, "fg" },
 124         { Opt_userspace, "retry=%s" },
 125
 126         { Opt_sloppy, "sloppy" },
 127
 128         { Opt_soft, "soft" },
 129         { Opt_hard, "hard" },
 130         { Opt_deprecated, "intr" },
 131         { Opt_deprecated, "nointr" },
 132         { Opt_posix, "posix" },
 133         { Opt_noposix, "noposix" },
 134         { Opt_cto, "cto" },
 135         { Opt_nocto, "nocto" },
 136         { Opt_ac, "ac" },
 137         { Opt_noac, "noac" },
 138         { Opt_lock, "lock" },
 139         { Opt_nolock, "nolock" },
 140         { Opt_udp, "udp" },
 141         { Opt_tcp, "tcp" },
 142         { Opt_rdma, "rdma" },
 143         { Opt_acl, "acl" },
 144         { Opt_noacl, "noacl" },
 145         { Opt_rdirplus, "rdirplus" },
 146         { Opt_nordirplus, "nordirplus" },
 147         { Opt_sharecache, "sharecache" },
 148         { Opt_nosharecache, "nosharecache" },
 149         { Opt_resvport, "resvport" },
 150         { Opt_noresvport, "noresvport" },
 151         { Opt_fscache, "fsc" },
 152         { Opt_nofscache, "nofsc" },
 153         { Opt_migration, "migration" },
 154         { Opt_nomigration, "nomigration" },
 155
 156         { Opt_port, "port=%s" },
 157         { Opt_rsize, "rsize=%s" },
 158         { Opt_wsize, "wsize=%s" },
 159         { Opt_bsize, "bsize=%s" },
 160         { Opt_timeo, "timeo=%s" },
 161         { Opt_retrans, "retrans=%s" },
 162         { Opt_acregmin, "acregmin=%s" },
 163         { Opt_acregmax, "acregmax=%s" },
 164         { Opt_acdirmin, "acdirmin=%s" },
 165         { Opt_acdirmax, "acdirmax=%s" },
 166         { Opt_actimeo, "actimeo=%s" },
 167         { Opt_namelen, "namlen=%s" },
 168         { Opt_mountport, "mountport=%s" },
 169         { Opt_mountvers, "mountvers=%s" },
 170         { Opt_minorversion, "minorversion=%s" },
 171
 172         { Opt_nfsvers, "nfsvers=%s" },
 173         { Opt_nfsvers, "vers=%s" },
 174
 175         { Opt_sec, "sec=%s" },
 176         { Opt_proto, "proto=%s" },
 177         { Opt_mountproto, "mountproto=%s" },
 178         { Opt_addr, "addr=%s" },
 179         { Opt_clientaddr, "clientaddr=%s" },
 180         { Opt_mounthost, "mounthost=%s" },
 181         { Opt_mountaddr, "mountaddr=%s" },
 182
 183         { Opt_lookupcache, "lookupcache=%s" },
 184         { Opt_fscache_uniq, "fsc=%s" },
 185         { Opt_local_lock, "local_lock=%s" },
 186
 187         /* The following needs to be listed after all other options */
 188         { Opt_nfsvers, "v%s" },
 189
 190         { Opt_err, NULL }
 191 };
 192
 193 enum {
 194         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 195
 196         Opt_xprt_err
 197 };
 198
 199 static const match_table_t nfs_xprt_protocol_tokens = {
 200         { Opt_xprt_udp, "udp" },
 201         { Opt_xprt_udp6, "udp6" },
 202         { Opt_xprt_tcp, "tcp" },
 203         { Opt_xprt_tcp6, "tcp6" },
 204         { Opt_xprt_rdma, "rdma" },
 205
 206         { Opt_xprt_err, NULL }
 207 };
 208
 209 enum {
 210         Opt_sec_none, Opt_sec_sys,
 211         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 212         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 213         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 214
 215         Opt_sec_err
 216 };
 217
 218 static const match_table_t nfs_secflavor_tokens = {
 219         { Opt_sec_none, "none" },
 220         { Opt_sec_none, "null" },
 221         { Opt_sec_sys, "sys" },
 222
 223         { Opt_sec_krb5, "krb5" },
 224         { Opt_sec_krb5i, "krb5i" },
 225         { Opt_sec_krb5p, "krb5p" },
 226
 227         { Opt_sec_lkey, "lkey" },
 228         { Opt_sec_lkeyi, "lkeyi" },
 229         { Opt_sec_lkeyp, "lkeyp" },
 230
 231         { Opt_sec_spkm, "spkm3" },
 232         { Opt_sec_spkmi, "spkm3i" },
 233         { Opt_sec_spkmp, "spkm3p" },
 234
 235         { Opt_sec_err, NULL }
 236 };
 237
 238 enum {
 239         Opt_lookupcache_all, Opt_lookupcache_positive,
 240         Opt_lookupcache_none,
 241
 242         Opt_lookupcache_err
 243 };
 244
 245 static match_table_t nfs_lookupcache_tokens = {
 246         { Opt_lookupcache_all, "all" },
 247         { Opt_lookupcache_positive, "pos" },
 248         { Opt_lookupcache_positive, "positive" },
 249         { Opt_lookupcache_none, "none" },
 250
 251         { Opt_lookupcache_err, NULL }
 252 };
 253
 254 enum {
 255         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 256         Opt_local_lock_none,
 257
 258         Opt_local_lock_err
 259 };
 260
 261 static match_table_t nfs_local_lock_tokens = {
 262         { Opt_local_lock_all, "all" },
 263         { Opt_local_lock_flock, "flock" },
 264         { Opt_local_lock_posix, "posix" },
 265         { Opt_local_lock_none, "none" },
 266
 267         { Opt_local_lock_err, NULL }
 268 };
 269
 270 enum {
 271         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 272         Opt_vers_4_1, Opt_vers_4_2,
 273
 274         Opt_vers_err
 275 };
 276
 277 static match_table_t nfs_vers_tokens = {
 278         { Opt_vers_2, "2" },
 279         { Opt_vers_3, "3" },
 280         { Opt_vers_4, "4" },
 281         { Opt_vers_4_0, "4.0" },
 282         { Opt_vers_4_1, "4.1" },
 283         { Opt_vers_4_2, "4.2" },
 284
 285         { Opt_vers_err, NULL }
 286 };
 287
 288 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 289                 int flags, const char *dev_name, void *raw_data);
 290
 291 struct file_system_type nfs_fs_type = {
 292         .owner          = THIS_MODULE,
 293         .name           = "nfs",
 294         .mount          = nfs_fs_mount,
 295         .kill_sb        = nfs_kill_super,
 296         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 297 };
 298 MODULE_ALIAS_FS("nfs");
 299 EXPORT_SYMBOL_GPL(nfs_fs_type);
 300
 301 struct file_system_type nfs_xdev_fs_type = {
 302         .owner          = THIS_MODULE,
 303         .name           = "nfs",
 304         .mount          = nfs_xdev_mount,
 305         .kill_sb        = nfs_kill_super,
 306         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 307 };
 308
 309 const struct super_operations nfs_sops = {
 310         .alloc_inode    = nfs_alloc_inode,
 311         .destroy_inode  = nfs_destroy_inode,
 312         .write_inode    = nfs_write_inode,
 313         .drop_inode     = nfs_drop_inode,
 314         .put_super      = nfs_put_super,
 315         .statfs         = nfs_statfs,
 316         .evict_inode    = nfs_evict_inode,
 317         .umount_begin   = nfs_umount_begin,
 318         .show_options   = nfs_show_options,
 319         .show_devname   = nfs_show_devname,
 320         .show_path      = nfs_show_path,
 321         .show_stats     = nfs_show_stats,
 322         .remount_fs     = nfs_remount,
 323 };
 324 EXPORT_SYMBOL_GPL(nfs_sops);
 325
 326 #if IS_ENABLED(CONFIG_NFS_V4)
 327 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 328 static int nfs4_validate_mount_data(void *options,
 329         struct nfs_parsed_mount_data *args, const char *dev_name);
 330
 331 struct file_system_type nfs4_fs_type = {
 332         .owner          = THIS_MODULE,
 333         .name           = "nfs4",
 334         .mount          = nfs_fs_mount,
 335         .kill_sb        = nfs_kill_super,
 336         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 337 };
 338 MODULE_ALIAS_FS("nfs4");
 339 MODULE_ALIAS("nfs4");
 340 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 341
 342 static int __init register_nfs4_fs(void)
 343 {
 344         return register_filesystem(&nfs4_fs_type);
 345 }
 346
 347 static void unregister_nfs4_fs(void)
 348 {
 349         unregister_filesystem(&nfs4_fs_type);
 350 }
 351 #else
 352 static int __init register_nfs4_fs(void)
 353 {
 354         return 0;
 355 }
 356
 357 static void unregister_nfs4_fs(void)
 358 {
 359 }
 360 #endif
 361
 362 static struct shrinker acl_shrinker = {
 363         .shrink         = nfs_access_cache_shrinker,
 364         .seeks          = DEFAULT_SEEKS,
 365 };
 366
 367 /*
 368  * Register the NFS filesystems
 369  */
 370 int __init register_nfs_fs(void)
 371 {
 372         int ret;
 373
 374         ret = register_filesystem(&nfs_fs_type);
 375         if (ret < 0)
 376                 goto error_0;
 377
 378         ret = register_nfs4_fs();
 379         if (ret < 0)
 380                 goto error_1;
 381
 382         ret = nfs_register_sysctl();
 383         if (ret < 0)
 384                 goto error_2;
 385         register_shrinker(&acl_shrinker);
 386         return 0;
 387
 388 error_2:
 389         unregister_nfs4_fs();
 390 error_1:
 391         unregister_filesystem(&nfs_fs_type);
 392 error_0:
 393         return ret;
 394 }
 395
 396 /*
 397  * Unregister the NFS filesystems
 398  */
 399 void __exit unregister_nfs_fs(void)
 400 {
 401         unregister_shrinker(&acl_shrinker);
 402         nfs_unregister_sysctl();
 403         unregister_nfs4_fs();
 404         unregister_filesystem(&nfs_fs_type);
 405 }
 406
 407 void nfs_sb_active(struct super_block *sb)
 408 {
 409         struct nfs_server *server = NFS_SB(sb);
 410
 411         if (atomic_inc_return(&server->active) == 1)
 412                 atomic_inc(&sb->s_active);
 413 }
 414 EXPORT_SYMBOL_GPL(nfs_sb_active);
 415
 416 void nfs_sb_deactive(struct super_block *sb)
 417 {
 418         struct nfs_server *server = NFS_SB(sb);
 419
 420         if (atomic_dec_and_test(&server->active))
 421                 deactivate_super(sb);
 422 }
 423 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 424
 425 /*
 426  * Deliver file system statistics to userspace
 427  */
 428 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 429 {
 430         struct nfs_server *server = NFS_SB(dentry->d_sb);
 431         unsigned char blockbits;
 432         unsigned long blockres;
 433         struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 434         struct nfs_fsstat res;
 435         int error = -ENOMEM;
 436
 437         res.fattr = nfs_alloc_fattr();
 438         if (res.fattr == NULL)
 439                 goto out_err;
 440
 441         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 442         if (unlikely(error == -ESTALE)) {
 443                 struct dentry *pd_dentry;
 444
 445                 pd_dentry = dget_parent(dentry);
 446                 if (pd_dentry != NULL) {
 447                         nfs_zap_caches(pd_dentry->d_inode);
 448                         dput(pd_dentry);
 449                 }
 450         }
 451         nfs_free_fattr(res.fattr);
 452         if (error < 0)
 453                 goto out_err;
 454
 455         buf->f_type = NFS_SUPER_MAGIC;
 456
 457         /*
 458          * Current versions of glibc do not correctly handle the
 459          * case where f_frsize != f_bsize.  Eventually we want to
 460          * report the value of wtmult in this field.
 461          */
 462         buf->f_frsize = dentry->d_sb->s_blocksize;
 463
 464         /*
 465          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 466          * are reported in units of f_frsize.  Linux hasn't had
 467          * an f_frsize field in its statfs struct until recently,
 468          * thus historically Linux's sys_statfs reports these
 469          * fields in units of f_bsize.
 470          */
 471         buf->f_bsize = dentry->d_sb->s_blocksize;
 472         blockbits = dentry->d_sb->s_blocksize_bits;
 473         blockres = (1 << blockbits) - 1;
 474         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 475         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 476         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 477
 478         buf->f_files = res.tfiles;
 479         buf->f_ffree = res.afiles;
 480
 481         buf->f_namelen = server->namelen;
 482
 483         return 0;
 484
 485  out_err:
 486         dprintk("%s: statfs error = %d\n", __func__, -error);
 487         return error;
 488 }
 489 EXPORT_SYMBOL_GPL(nfs_statfs);
 490
 491 /*
 492  * Map the security flavour number to a name
 493  */
 494 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 495 {
 496         static const struct {
 497                 rpc_authflavor_t flavour;
 498                 const char *str;
 499         } sec_flavours[] = {
 500                 { RPC_AUTH_NULL, "null" },
 501                 { RPC_AUTH_UNIX, "sys" },
 502                 { RPC_AUTH_GSS_KRB5, "krb5" },
 503                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 504                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 505                 { RPC_AUTH_GSS_LKEY, "lkey" },
 506                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 507                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 508                 { RPC_AUTH_GSS_SPKM, "spkm" },
 509                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 510                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 511                 { UINT_MAX, "unknown" }
 512         };
 513         int i;
 514
 515         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 516                 if (sec_flavours[i].flavour == flavour)
 517                         break;
 518         }
 519         return sec_flavours[i].str;
 520 }
 521
 522 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 523                                   int showdefaults)
 524 {
 525         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 526
 527         seq_printf(m, ",mountproto=");
 528         switch (sap->sa_family) {
 529         case AF_INET:
 530                 switch (nfss->mountd_protocol) {
 531                 case IPPROTO_UDP:
 532                         seq_printf(m, RPCBIND_NETID_UDP);
 533                         break;
 534                 case IPPROTO_TCP:
 535                         seq_printf(m, RPCBIND_NETID_TCP);
 536                         break;
 537                 default:
 538                         if (showdefaults)
 539                                 seq_printf(m, "auto");
 540                 }
 541                 break;
 542         case AF_INET6:
 543                 switch (nfss->mountd_protocol) {
 544                 case IPPROTO_UDP:
 545                         seq_printf(m, RPCBIND_NETID_UDP6);
 546                         break;
 547                 case IPPROTO_TCP:
 548                         seq_printf(m, RPCBIND_NETID_TCP6);
 549                         break;
 550                 default:
 551                         if (showdefaults)
 552                                 seq_printf(m, "auto");
 553                 }
 554                 break;
 555         default:
 556                 if (showdefaults)
 557                         seq_printf(m, "auto");
 558         }
 559 }
 560
 561 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 562                                     int showdefaults)
 563 {
 564         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 565
 566         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 567                 return;
 568
 569         switch (sap->sa_family) {
 570         case AF_INET: {
 571                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 572                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 573                 break;
 574         }
 575         case AF_INET6: {
 576                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 577                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 578                 break;
 579         }
 580         default:
 581                 if (showdefaults)
 582                         seq_printf(m, ",mountaddr=unspecified");
 583         }
 584
 585         if (nfss->mountd_version || showdefaults)
 586                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 587         if ((nfss->mountd_port &&
 588                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 589                 showdefaults)
 590                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 591
 592         nfs_show_mountd_netid(m, nfss, showdefaults);
 593 }
 594
 595 #if IS_ENABLED(CONFIG_NFS_V4)
 596 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 597                                     int showdefaults)
 598 {
 599         struct nfs_client *clp = nfss->nfs_client;
 600
 601         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 602 }
 603 #else
 604 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 605                                     int showdefaults)
 606 {
 607 }
 608 #endif
 609
 610 static void nfs_show_nfs_version(struct seq_file *m,
 611                 unsigned int version,
 612                 unsigned int minorversion)
 613 {
 614         seq_printf(m, ",vers=%u", version);
 615         if (version == 4)
 616                 seq_printf(m, ".%u", minorversion);
 617 }
 618
 619 /*
 620  * Describe the mount options in force on this server representation
 621  */
 622 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 623                                    int showdefaults)
 624 {
 625         static const struct proc_nfs_info {
 626                 int flag;
 627                 const char *str;
 628                 const char *nostr;
 629         } nfs_info[] = {
 630                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 631                 { NFS_MOUNT_POSIX, ",posix", "" },
 632                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 633                 { NFS_MOUNT_NOAC, ",noac", "" },
 634                 { NFS_MOUNT_NONLM, ",nolock", "" },
 635                 { NFS_MOUNT_NOACL, ",noacl", "" },
 636                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 637                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 638                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 639                 { 0, NULL, NULL }
 640         };
 641         const struct proc_nfs_info *nfs_infop;
 642         struct nfs_client *clp = nfss->nfs_client;
 643         u32 version = clp->rpc_ops->version;
 644         int local_flock, local_fcntl;
 645
 646         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 647         seq_printf(m, ",rsize=%u", nfss->rsize);
 648         seq_printf(m, ",wsize=%u", nfss->wsize);
 649         if (nfss->bsize != 0)
 650                 seq_printf(m, ",bsize=%u", nfss->bsize);
 651         seq_printf(m, ",namlen=%u", nfss->namelen);
 652         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 653                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 654         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 655                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 656         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 657                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 658         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 659                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 660         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 661                 if (nfss->flags & nfs_infop->flag)
 662                         seq_puts(m, nfs_infop->str);
 663                 else
 664                         seq_puts(m, nfs_infop->nostr);
 665         }
 666         rcu_read_lock();
 667         seq_printf(m, ",proto=%s",
 668                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 669         rcu_read_unlock();
 670         if (version == 4) {
 671                 if (nfss->port != NFS_PORT)
 672                         seq_printf(m, ",port=%u", nfss->port);
 673         } else
 674                 if (nfss->port)
 675                         seq_printf(m, ",port=%u", nfss->port);
 676
 677         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 678         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 679         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 680
 681         if (version != 4)
 682                 nfs_show_mountd_options(m, nfss, showdefaults);
 683         else
 684                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 685
 686         if (nfss->options & NFS_OPTION_FSCACHE)
 687                 seq_printf(m, ",fsc");
 688
 689         if (nfss->options & NFS_OPTION_MIGRATION)
 690                 seq_printf(m, ",migration");
 691
 692         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 693                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 694                         seq_printf(m, ",lookupcache=none");
 695                 else
 696                         seq_printf(m, ",lookupcache=pos");
 697         }
 698
 699         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 700         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 701
 702         if (!local_flock && !local_fcntl)
 703                 seq_printf(m, ",local_lock=none");
 704         else if (local_flock && local_fcntl)
 705                 seq_printf(m, ",local_lock=all");
 706         else if (local_flock)
 707                 seq_printf(m, ",local_lock=flock");
 708         else
 709                 seq_printf(m, ",local_lock=posix");
 710 }
 711
 712 /*
 713  * Describe the mount options on this VFS mountpoint
 714  */
 715 int nfs_show_options(struct seq_file *m, struct dentry *root)
 716 {
 717         struct nfs_server *nfss = NFS_SB(root->d_sb);
 718
 719         nfs_show_mount_options(m, nfss, 0);
 720
 721         rcu_read_lock();
 722         seq_printf(m, ",addr=%s",
 723                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 724                                                         RPC_DISPLAY_ADDR));
 725         rcu_read_unlock();
 726
 727         return 0;
 728 }
 729 EXPORT_SYMBOL_GPL(nfs_show_options);
 730
 731 #if IS_ENABLED(CONFIG_NFS_V4)
 732 #ifdef CONFIG_NFS_V4_1
 733 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 734 {
 735         if (nfs4_has_session(server->nfs_client))
 736                 seq_printf(m, ",sessions");
 737 }
 738 #else
 739 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 740 #endif
 741 #endif
 742
 743 #ifdef CONFIG_NFS_V4_1
 744 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 745 {
 746         seq_printf(m, ",pnfs=");
 747         if (server->pnfs_curr_ld)
 748                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 749         else
 750                 seq_printf(m, "not configured");
 751 }
 752
 753 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 754 {
 755         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 756                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 757                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 758                            "date='%llu,%u'",
 759                            impl_id->name, impl_id->domain,
 760                            impl_id->date.seconds, impl_id->date.nseconds);
 761         }
 762 }
 763 #else
 764 #if IS_ENABLED(CONFIG_NFS_V4)
 765 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 766 {
 767 }
 768 #endif
 769 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 770 {
 771 }
 772 #endif
 773
 774 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 775 {
 776         char *page = (char *) __get_free_page(GFP_KERNEL);
 777         char *devname, *dummy;
 778         int err = 0;
 779         if (!page)
 780                 return -ENOMEM;
 781         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 782         if (IS_ERR(devname))
 783                 err = PTR_ERR(devname);
 784         else
 785                 seq_escape(m, devname, " \t\n\\");
 786         free_page((unsigned long)page);
 787         return err;
 788 }
 789 EXPORT_SYMBOL_GPL(nfs_show_devname);
 790
 791 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 792 {
 793         seq_puts(m, "/");
 794         return 0;
 795 }
 796 EXPORT_SYMBOL_GPL(nfs_show_path);
 797
 798 /*
 799  * Present statistical information for this VFS mountpoint
 800  */
 801 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 802 {
 803         int i, cpu;
 804         struct nfs_server *nfss = NFS_SB(root->d_sb);
 805         struct rpc_auth *auth = nfss->client->cl_auth;
 806         struct nfs_iostats totals = { };
 807
 808         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 809
 810         /*
 811          * Display all mount option settings
 812          */
 813         seq_printf(m, "\n\topts:\t");
 814         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 815         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 816         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 817         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 818         nfs_show_mount_options(m, nfss, 1);
 819
 820         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 821
 822         show_implementation_id(m, nfss);
 823
 824         seq_printf(m, "\n\tcaps:\t");
 825         seq_printf(m, "caps=0x%x", nfss->caps);
 826         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 827         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 828         seq_printf(m, ",bsize=%u", nfss->bsize);
 829         seq_printf(m, ",namlen=%u", nfss->namelen);
 830
 831 #if IS_ENABLED(CONFIG_NFS_V4)
 832         if (nfss->nfs_client->rpc_ops->version == 4) {
 833                 seq_printf(m, "\n\tnfsv4:\t");
 834                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 835                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 836                 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
 837                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 838                 show_sessions(m, nfss);
 839                 show_pnfs(m, nfss);
 840         }
 841 #endif
 842
 843         /*
 844          * Display security flavor in effect for this mount
 845          */
 846         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 847         if (auth->au_flavor)
 848                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 849
 850         /*
 851          * Display superblock I/O counters
 852          */
 853         for_each_possible_cpu(cpu) {
 854                 struct nfs_iostats *stats;
 855
 856                 preempt_disable();
 857                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 858
 859                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 860                         totals.events[i] += stats->events[i];
 861                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 862                         totals.bytes[i] += stats->bytes[i];
 863 #ifdef CONFIG_NFS_FSCACHE
 864                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 865                         totals.fscache[i] += stats->fscache[i];
 866 #endif
 867
 868                 preempt_enable();
 869         }
 870
 871         seq_printf(m, "\n\tevents:\t");
 872         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 873                 seq_printf(m, "%lu ", totals.events[i]);
 874         seq_printf(m, "\n\tbytes:\t");
 875         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 876                 seq_printf(m, "%Lu ", totals.bytes[i]);
 877 #ifdef CONFIG_NFS_FSCACHE
 878         if (nfss->options & NFS_OPTION_FSCACHE) {
 879                 seq_printf(m, "\n\tfsc:\t");
 880                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 881                         seq_printf(m, "%Lu ", totals.bytes[i]);
 882         }
 883 #endif
 884         seq_printf(m, "\n");
 885
 886         rpc_print_iostats(m, nfss->client);
 887
 888         return 0;
 889 }
 890 EXPORT_SYMBOL_GPL(nfs_show_stats);
 891
 892 /*
 893  * Begin unmount by attempting to remove all automounted mountpoints we added
 894  * in response to xdev traversals and referrals
 895  */
 896 void nfs_umount_begin(struct super_block *sb)
 897 {
 898         struct nfs_server *server;
 899         struct rpc_clnt *rpc;
 900
 901         server = NFS_SB(sb);
 902         /* -EIO all pending I/O */
 903         rpc = server->client_acl;
 904         if (!IS_ERR(rpc))
 905                 rpc_killall_tasks(rpc);
 906         rpc = server->client;
 907         if (!IS_ERR(rpc))
 908                 rpc_killall_tasks(rpc);
 909 }
 910 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 911
 912 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 913 {
 914         struct nfs_parsed_mount_data *data;
 915
 916         data = kzalloc(sizeof(*data), GFP_KERNEL);
 917         if (data) {
 918                 data->acregmin          = NFS_DEF_ACREGMIN;
 919                 data->acregmax          = NFS_DEF_ACREGMAX;
 920                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 921                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 922                 data->mount_server.port = NFS_UNSPEC_PORT;
 923                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 924                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 925                 data->auth_flavors[0]   = RPC_AUTH_MAXFLAVOR;
 926                 data->auth_flavor_len   = 0;
 927                 data->minorversion      = 0;
 928                 data->need_mount        = true;
 929                 data->net               = current->nsproxy->net_ns;
 930                 security_init_mnt_opts(&data->lsm_opts);
 931         }
 932         return data;
 933 }
 934
 935 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 936 {
 937         if (data) {
 938                 kfree(data->client_address);
 939                 kfree(data->mount_server.hostname);
 940                 kfree(data->nfs_server.export_path);
 941                 kfree(data->nfs_server.hostname);
 942                 kfree(data->fscache_uniq);
 943                 security_free_mnt_opts(&data->lsm_opts);
 944                 kfree(data);
 945         }
 946 }
 947
 948 /*
 949  * Sanity-check a server address provided by the mount command.
 950  *
 951  * Address family must be initialized, and address must not be
 952  * the ANY address for that family.
 953  */
 954 static int nfs_verify_server_address(struct sockaddr *addr)
 955 {
 956         switch (addr->sa_family) {
 957         case AF_INET: {
 958                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 959                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 960         }
 961         case AF_INET6: {
 962                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 963                 return !ipv6_addr_any(sa);
 964         }
 965         }
 966
 967         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 968         return 0;
 969 }
 970
 971 /*
 972  * Select between a default port value and a user-specified port value.
 973  * If a zero value is set, then autobind will be used.
 974  */
 975 static void nfs_set_port(struct sockaddr *sap, int *port,
 976                                  const unsigned short default_port)
 977 {
 978         if (*port == NFS_UNSPEC_PORT)
 979                 *port = default_port;
 980
 981         rpc_set_port(sap, *port);
 982 }
 983
 984 /*
 985  * Sanity check the NFS transport protocol.
 986  *
 987  */
 988 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 989 {
 990         switch (mnt->nfs_server.protocol) {
 991         case XPRT_TRANSPORT_UDP:
 992         case XPRT_TRANSPORT_TCP:
 993         case XPRT_TRANSPORT_RDMA:
 994                 break;
 995         default:
 996                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 997         }
 998 }
 999
1000 /*
1001  * For text based NFSv2/v3 mounts, the mount protocol transport default
1002  * settings should depend upon the specified NFS transport.
1003  */
1004 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1005 {
1006         nfs_validate_transport_protocol(mnt);
1007
1008         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1009             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1010                         return;
1011         switch (mnt->nfs_server.protocol) {
1012         case XPRT_TRANSPORT_UDP:
1013                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1014                 break;
1015         case XPRT_TRANSPORT_TCP:
1016         case XPRT_TRANSPORT_RDMA:
1017                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1018         }
1019 }
1020
1021 static void nfs_set_auth_parsed_mount_data(struct nfs_parsed_mount_data *data,
1022                 rpc_authflavor_t pseudoflavor)
1023 {
1024         data->auth_flavors[0] = pseudoflavor;
1025         data->auth_flavor_len = 1;
1026 }
1027
1028 /*
1029  * Parse the value of the 'sec=' option.
1030  */
1031 static int nfs_parse_security_flavors(char *value,
1032                                       struct nfs_parsed_mount_data *mnt)
1033 {
1034         substring_t args[MAX_OPT_ARGS];
1035
1036         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1037
1038         switch (match_token(value, nfs_secflavor_tokens, args)) {
1039         case Opt_sec_none:
1040                 mnt->auth_flavors[0] = RPC_AUTH_NULL;
1041                 break;
1042         case Opt_sec_sys:
1043                 mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1044                 break;
1045         case Opt_sec_krb5:
1046                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1047                 break;
1048         case Opt_sec_krb5i:
1049                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1050                 break;
1051         case Opt_sec_krb5p:
1052                 mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1053                 break;
1054         case Opt_sec_lkey:
1055                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1056                 break;
1057         case Opt_sec_lkeyi:
1058                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1059                 break;
1060         case Opt_sec_lkeyp:
1061                 mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1062                 break;
1063         case Opt_sec_spkm:
1064                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1065                 break;
1066         case Opt_sec_spkmi:
1067                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1068                 break;
1069         case Opt_sec_spkmp:
1070                 mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1071                 break;
1072         default:
1073                 return 0;
1074         }
1075
1076         mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1077         mnt->auth_flavor_len = 1;
1078         return 1;
1079 }
1080
1081 static int nfs_parse_version_string(char *string,
1082                 struct nfs_parsed_mount_data *mnt,
1083                 substring_t *args)
1084 {
1085         mnt->flags &= ~NFS_MOUNT_VER3;
1086         switch (match_token(string, nfs_vers_tokens, args)) {
1087         case Opt_vers_2:
1088                 mnt->version = 2;
1089                 break;
1090         case Opt_vers_3:
1091                 mnt->flags |= NFS_MOUNT_VER3;
1092                 mnt->version = 3;
1093                 break;
1094         case Opt_vers_4:
1095                 /* Backward compatibility option. In future,
1096                  * the mount program should always supply
1097                  * a NFSv4 minor version number.
1098                  */
1099                 mnt->version = 4;
1100                 break;
1101         case Opt_vers_4_0:
1102                 mnt->version = 4;
1103                 mnt->minorversion = 0;
1104                 break;
1105         case Opt_vers_4_1:
1106                 mnt->version = 4;
1107                 mnt->minorversion = 1;
1108                 break;
1109         case Opt_vers_4_2:
1110                 mnt->version = 4;
1111                 mnt->minorversion = 2;
1112                 break;
1113         default:
1114                 return 0;
1115         }
1116         return 1;
1117 }
1118
1119 static int nfs_get_option_str(substring_t args[], char **option)
1120 {
1121         kfree(*option);
1122         *option = match_strdup(args);
1123         return !*option;
1124 }
1125
1126 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1127 {
1128         int rc;
1129         char *string;
1130
1131         string = match_strdup(args);
1132         if (string == NULL)
1133                 return -ENOMEM;
1134         rc = kstrtoul(string, 10, option);
1135         kfree(string);
1136
1137         return rc;
1138 }
1139
1140 /*
1141  * Error-check and convert a string of mount options from user space into
1142  * a data structure.  The whole mount string is processed; bad options are
1143  * skipped as they are encountered.  If there were no errors, return 1;
1144  * otherwise return 0 (zero).
1145  */
1146 static int nfs_parse_mount_options(char *raw,
1147                                    struct nfs_parsed_mount_data *mnt)
1148 {
1149         char *p, *string, *secdata;
1150         int rc, sloppy = 0, invalid_option = 0;
1151         unsigned short protofamily = AF_UNSPEC;
1152         unsigned short mountfamily = AF_UNSPEC;
1153
1154         if (!raw) {
1155                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1156                 return 1;
1157         }
1158         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1159
1160         secdata = alloc_secdata();
1161         if (!secdata)
1162                 goto out_nomem;
1163
1164         rc = security_sb_copy_data(raw, secdata);
1165         if (rc)
1166                 goto out_security_failure;
1167
1168         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1169         if (rc)
1170                 goto out_security_failure;
1171
1172         free_secdata(secdata);
1173
1174         while ((p = strsep(&raw, ",")) != NULL) {
1175                 substring_t args[MAX_OPT_ARGS];
1176                 unsigned long option;
1177                 int token;
1178
1179                 if (!*p)
1180                         continue;
1181
1182                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1183
1184                 token = match_token(p, nfs_mount_option_tokens, args);
1185                 switch (token) {
1186
1187                 /*
1188                  * boolean options:  foo/nofoo
1189                  */
1190                 case Opt_soft:
1191                         mnt->flags |= NFS_MOUNT_SOFT;
1192                         break;
1193                 case Opt_hard:
1194                         mnt->flags &= ~NFS_MOUNT_SOFT;
1195                         break;
1196                 case Opt_posix:
1197                         mnt->flags |= NFS_MOUNT_POSIX;
1198                         break;
1199                 case Opt_noposix:
1200                         mnt->flags &= ~NFS_MOUNT_POSIX;
1201                         break;
1202                 case Opt_cto:
1203                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1204                         break;
1205                 case Opt_nocto:
1206                         mnt->flags |= NFS_MOUNT_NOCTO;
1207                         break;
1208                 case Opt_ac:
1209                         mnt->flags &= ~NFS_MOUNT_NOAC;
1210                         break;
1211                 case Opt_noac:
1212                         mnt->flags |= NFS_MOUNT_NOAC;
1213                         break;
1214                 case Opt_lock:
1215                         mnt->flags &= ~NFS_MOUNT_NONLM;
1216                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1217                                         NFS_MOUNT_LOCAL_FCNTL);
1218                         break;
1219                 case Opt_nolock:
1220                         mnt->flags |= NFS_MOUNT_NONLM;
1221                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1222                                        NFS_MOUNT_LOCAL_FCNTL);
1223                         break;
1224                 case Opt_udp:
1225                         mnt->flags &= ~NFS_MOUNT_TCP;
1226                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1227                         break;
1228                 case Opt_tcp:
1229                         mnt->flags |= NFS_MOUNT_TCP;
1230                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1231                         break;
1232                 case Opt_rdma:
1233                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1234                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1235                         xprt_load_transport(p);
1236                         break;
1237                 case Opt_acl:
1238                         mnt->flags &= ~NFS_MOUNT_NOACL;
1239                         break;
1240                 case Opt_noacl:
1241                         mnt->flags |= NFS_MOUNT_NOACL;
1242                         break;
1243                 case Opt_rdirplus:
1244                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1245                         break;
1246                 case Opt_nordirplus:
1247                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1248                         break;
1249                 case Opt_sharecache:
1250                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1251                         break;
1252                 case Opt_nosharecache:
1253                         mnt->flags |= NFS_MOUNT_UNSHARED;
1254                         break;
1255                 case Opt_resvport:
1256                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1257                         break;
1258                 case Opt_noresvport:
1259                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1260                         break;
1261                 case Opt_fscache:
1262                         mnt->options |= NFS_OPTION_FSCACHE;
1263                         kfree(mnt->fscache_uniq);
1264                         mnt->fscache_uniq = NULL;
1265                         break;
1266                 case Opt_nofscache:
1267                         mnt->options &= ~NFS_OPTION_FSCACHE;
1268                         kfree(mnt->fscache_uniq);
1269                         mnt->fscache_uniq = NULL;
1270                         break;
1271                 case Opt_migration:
1272                         mnt->options |= NFS_OPTION_MIGRATION;
1273                         break;
1274                 case Opt_nomigration:
1275                         mnt->options &= NFS_OPTION_MIGRATION;
1276                         break;
1277
1278                 /*
1279                  * options that take numeric values
1280                  */
1281                 case Opt_port:
1282                         if (nfs_get_option_ul(args, &option) ||
1283                             option > USHRT_MAX)
1284                                 goto out_invalid_value;
1285                         mnt->nfs_server.port = option;
1286                         break;
1287                 case Opt_rsize:
1288                         if (nfs_get_option_ul(args, &option))
1289                                 goto out_invalid_value;
1290                         mnt->rsize = option;
1291                         break;
1292                 case Opt_wsize:
1293                         if (nfs_get_option_ul(args, &option))
1294                                 goto out_invalid_value;
1295                         mnt->wsize = option;
1296                         break;
1297                 case Opt_bsize:
1298                         if (nfs_get_option_ul(args, &option))
1299                                 goto out_invalid_value;
1300                         mnt->bsize = option;
1301                         break;
1302                 case Opt_timeo:
1303                         if (nfs_get_option_ul(args, &option) || option == 0)
1304                                 goto out_invalid_value;
1305                         mnt->timeo = option;
1306                         break;
1307                 case Opt_retrans:
1308                         if (nfs_get_option_ul(args, &option) || option == 0)
1309                                 goto out_invalid_value;
1310                         mnt->retrans = option;
1311                         break;
1312                 case Opt_acregmin:
1313                         if (nfs_get_option_ul(args, &option))
1314                                 goto out_invalid_value;
1315                         mnt->acregmin = option;
1316                         break;
1317                 case Opt_acregmax:
1318                         if (nfs_get_option_ul(args, &option))
1319                                 goto out_invalid_value;
1320                         mnt->acregmax = option;
1321                         break;
1322                 case Opt_acdirmin:
1323                         if (nfs_get_option_ul(args, &option))
1324                                 goto out_invalid_value;
1325                         mnt->acdirmin = option;
1326                         break;
1327                 case Opt_acdirmax:
1328                         if (nfs_get_option_ul(args, &option))
1329                                 goto out_invalid_value;
1330                         mnt->acdirmax = option;
1331                         break;
1332                 case Opt_actimeo:
1333                         if (nfs_get_option_ul(args, &option))
1334                                 goto out_invalid_value;
1335                         mnt->acregmin = mnt->acregmax =
1336                         mnt->acdirmin = mnt->acdirmax = option;
1337                         break;
1338                 case Opt_namelen:
1339                         if (nfs_get_option_ul(args, &option))
1340                                 goto out_invalid_value;
1341                         mnt->namlen = option;
1342                         break;
1343                 case Opt_mountport:
1344                         if (nfs_get_option_ul(args, &option) ||
1345                             option > USHRT_MAX)
1346                                 goto out_invalid_value;
1347                         mnt->mount_server.port = option;
1348                         break;
1349                 case Opt_mountvers:
1350                         if (nfs_get_option_ul(args, &option) ||
1351                             option < NFS_MNT_VERSION ||
1352                             option > NFS_MNT3_VERSION)
1353                                 goto out_invalid_value;
1354                         mnt->mount_server.version = option;
1355                         break;
1356                 case Opt_minorversion:
1357                         if (nfs_get_option_ul(args, &option))
1358                                 goto out_invalid_value;
1359                         if (option > NFS4_MAX_MINOR_VERSION)
1360                                 goto out_invalid_value;
1361                         mnt->minorversion = option;
1362                         break;
1363
1364                 /*
1365                  * options that take text values
1366                  */
1367                 case Opt_nfsvers:
1368                         string = match_strdup(args);
1369                         if (string == NULL)
1370                                 goto out_nomem;
1371                         rc = nfs_parse_version_string(string, mnt, args);
1372                         kfree(string);
1373                         if (!rc)
1374                                 goto out_invalid_value;
1375                         break;
1376                 case Opt_sec:
1377                         string = match_strdup(args);
1378                         if (string == NULL)
1379                                 goto out_nomem;
1380                         rc = nfs_parse_security_flavors(string, mnt);
1381                         kfree(string);
1382                         if (!rc) {
1383                                 dfprintk(MOUNT, "NFS:   unrecognized "
1384                                                 "security flavor\n");
1385                                 return 0;
1386                         }
1387                         break;
1388                 case Opt_proto:
1389                         string = match_strdup(args);
1390                         if (string == NULL)
1391                                 goto out_nomem;
1392                         token = match_token(string,
1393                                             nfs_xprt_protocol_tokens, args);
1394
1395                         protofamily = AF_INET;
1396                         switch (token) {
1397                         case Opt_xprt_udp6:
1398                                 protofamily = AF_INET6;
1399                         case Opt_xprt_udp:
1400                                 mnt->flags &= ~NFS_MOUNT_TCP;
1401                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1402                                 break;
1403                         case Opt_xprt_tcp6:
1404                                 protofamily = AF_INET6;
1405                         case Opt_xprt_tcp:
1406                                 mnt->flags |= NFS_MOUNT_TCP;
1407                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1408                                 break;
1409                         case Opt_xprt_rdma:
1410                                 /* vector side protocols to TCP */
1411                                 mnt->flags |= NFS_MOUNT_TCP;
1412                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1413                                 xprt_load_transport(string);
1414                                 break;
1415                         default:
1416                                 dfprintk(MOUNT, "NFS:   unrecognized "
1417                                                 "transport protocol\n");
1418                                 kfree(string);
1419                                 return 0;
1420                         }
1421                         kfree(string);
1422                         break;
1423                 case Opt_mountproto:
1424                         string = match_strdup(args);
1425                         if (string == NULL)
1426                                 goto out_nomem;
1427                         token = match_token(string,
1428                                             nfs_xprt_protocol_tokens, args);
1429                         kfree(string);
1430
1431                         mountfamily = AF_INET;
1432                         switch (token) {
1433                         case Opt_xprt_udp6:
1434                                 mountfamily = AF_INET6;
1435                         case Opt_xprt_udp:
1436                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1437                                 break;
1438                         case Opt_xprt_tcp6:
1439                                 mountfamily = AF_INET6;
1440                         case Opt_xprt_tcp:
1441                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1442                                 break;
1443                         case Opt_xprt_rdma: /* not used for side protocols */
1444                         default:
1445                                 dfprintk(MOUNT, "NFS:   unrecognized "
1446                                                 "transport protocol\n");
1447                                 return 0;
1448                         }
1449                         break;
1450                 case Opt_addr:
1451                         string = match_strdup(args);
1452                         if (string == NULL)
1453                                 goto out_nomem;
1454                         mnt->nfs_server.addrlen =
1455                                 rpc_pton(mnt->net, string, strlen(string),
1456                                         (struct sockaddr *)
1457                                         &mnt->nfs_server.address,
1458                                         sizeof(mnt->nfs_server.address));
1459                         kfree(string);
1460                         if (mnt->nfs_server.addrlen == 0)
1461                                 goto out_invalid_address;
1462                         break;
1463                 case Opt_clientaddr:
1464                         if (nfs_get_option_str(args, &mnt->client_address))
1465                                 goto out_nomem;
1466                         break;
1467                 case Opt_mounthost:
1468                         if (nfs_get_option_str(args,
1469                                                &mnt->mount_server.hostname))
1470                                 goto out_nomem;
1471                         break;
1472                 case Opt_mountaddr:
1473                         string = match_strdup(args);
1474                         if (string == NULL)
1475                                 goto out_nomem;
1476                         mnt->mount_server.addrlen =
1477                                 rpc_pton(mnt->net, string, strlen(string),
1478                                         (struct sockaddr *)
1479                                         &mnt->mount_server.address,
1480                                         sizeof(mnt->mount_server.address));
1481                         kfree(string);
1482                         if (mnt->mount_server.addrlen == 0)
1483                                 goto out_invalid_address;
1484                         break;
1485                 case Opt_lookupcache:
1486                         string = match_strdup(args);
1487                         if (string == NULL)
1488                                 goto out_nomem;
1489                         token = match_token(string,
1490                                         nfs_lookupcache_tokens, args);
1491                         kfree(string);
1492                         switch (token) {
1493                                 case Opt_lookupcache_all:
1494                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1495                                         break;
1496                                 case Opt_lookupcache_positive:
1497                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1498                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1499                                         break;
1500                                 case Opt_lookupcache_none:
1501                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1502                                         break;
1503                                 default:
1504                                         dfprintk(MOUNT, "NFS:   invalid "
1505                                                         "lookupcache argument\n");
1506                                         return 0;
1507                         };
1508                         break;
1509                 case Opt_fscache_uniq:
1510                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1511                                 goto out_nomem;
1512                         mnt->options |= NFS_OPTION_FSCACHE;
1513                         break;
1514                 case Opt_local_lock:
1515                         string = match_strdup(args);
1516                         if (string == NULL)
1517                                 goto out_nomem;
1518                         token = match_token(string, nfs_local_lock_tokens,
1519                                         args);
1520                         kfree(string);
1521                         switch (token) {
1522                         case Opt_local_lock_all:
1523                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1524                                                NFS_MOUNT_LOCAL_FCNTL);
1525                                 break;
1526                         case Opt_local_lock_flock:
1527                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1528                                 break;
1529                         case Opt_local_lock_posix:
1530                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1531                                 break;
1532                         case Opt_local_lock_none:
1533                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1534                                                 NFS_MOUNT_LOCAL_FCNTL);
1535                                 break;
1536                         default:
1537                                 dfprintk(MOUNT, "NFS:   invalid "
1538                                                 "local_lock argument\n");
1539                                 return 0;
1540                         };
1541                         break;
1542
1543                 /*
1544                  * Special options
1545                  */
1546                 case Opt_sloppy:
1547                         sloppy = 1;
1548                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1549                         break;
1550                 case Opt_userspace:
1551                 case Opt_deprecated:
1552                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1553                                         "'%s'\n", p);
1554                         break;
1555
1556                 default:
1557                         invalid_option = 1;
1558                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1559                                         "'%s'\n", p);
1560                 }
1561         }
1562
1563         if (!sloppy && invalid_option)
1564                 return 0;
1565
1566         if (mnt->minorversion && mnt->version != 4)
1567                 goto out_minorversion_mismatch;
1568
1569         if (mnt->options & NFS_OPTION_MIGRATION &&
1570             mnt->version != 4 && mnt->minorversion != 0)
1571                 goto out_migration_misuse;
1572
1573         /*
1574          * verify that any proto=/mountproto= options match the address
1575          * families in the addr=/mountaddr= options.
1576          */
1577         if (protofamily != AF_UNSPEC &&
1578             protofamily != mnt->nfs_server.address.ss_family)
1579                 goto out_proto_mismatch;
1580
1581         if (mountfamily != AF_UNSPEC) {
1582                 if (mnt->mount_server.addrlen) {
1583                         if (mountfamily != mnt->mount_server.address.ss_family)
1584                                 goto out_mountproto_mismatch;
1585                 } else {
1586                         if (mountfamily != mnt->nfs_server.address.ss_family)
1587                                 goto out_mountproto_mismatch;
1588                 }
1589         }
1590
1591         return 1;
1592
1593 out_mountproto_mismatch:
1594         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1595                          "option\n");
1596         return 0;
1597 out_proto_mismatch:
1598         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1599         return 0;
1600 out_invalid_address:
1601         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1602         return 0;
1603 out_invalid_value:
1604         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1605         return 0;
1606 out_minorversion_mismatch:
1607         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1608                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1609         return 0;
1610 out_migration_misuse:
1611         printk(KERN_INFO
1612                 "NFS: 'migration' not supported for this NFS version\n");
1613         return 0;
1614 out_nomem:
1615         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1616         return 0;
1617 out_security_failure:
1618         free_secdata(secdata);
1619         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1620         return 0;
1621 }
1622
1623 /*
1624  * Ensure that the specified authtype in args->auth_flavors[0] is supported by
1625  * the server. Returns 0 if it's ok, and -EACCES if not.
1626  */
1627 static int nfs_verify_authflavor(struct nfs_parsed_mount_data *args,
1628                         rpc_authflavor_t *server_authlist, unsigned int count)
1629 {
1630         unsigned int i;
1631
1632         /*
1633          * If the sec= mount option is used, the specified flavor or AUTH_NULL
1634          * must be in the list returned by the server.
1635          *
1636          * AUTH_NULL has a special meaning when it's in the server list - it
1637          * means that the server will ignore the rpc creds, so any flavor
1638          * can be used.
1639          */
1640         for (i = 0; i < count; i++) {
1641                 if (args->auth_flavors[0] == server_authlist[i] ||
1642                     server_authlist[i] == RPC_AUTH_NULL)
1643                         goto out;
1644         }
1645
1646         dfprintk(MOUNT, "NFS: auth flavor %u not supported by server\n",
1647                 args->auth_flavors[0]);
1648         return -EACCES;
1649
1650 out:
1651         dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->auth_flavors[0]);
1652         return 0;
1653 }
1654
1655 /*
1656  * Use the remote server's MOUNT service to request the NFS file handle
1657  * corresponding to the provided path.
1658  */
1659 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1660                              struct nfs_fh *root_fh,
1661                              rpc_authflavor_t *server_authlist,
1662                              unsigned int *server_authlist_len)
1663 {
1664         struct nfs_mount_request request = {
1665                 .sap            = (struct sockaddr *)
1666                                                 &args->mount_server.address,
1667                 .dirpath        = args->nfs_server.export_path,
1668                 .protocol       = args->mount_server.protocol,
1669                 .fh             = root_fh,
1670                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1671                 .auth_flav_len  = server_authlist_len,
1672                 .auth_flavs     = server_authlist,
1673                 .net            = args->net,
1674         };
1675         int status;
1676
1677         if (args->mount_server.version == 0) {
1678                 switch (args->version) {
1679                         default:
1680                                 args->mount_server.version = NFS_MNT3_VERSION;
1681                                 break;
1682                         case 2:
1683                                 args->mount_server.version = NFS_MNT_VERSION;
1684                 }
1685         }
1686         request.version = args->mount_server.version;
1687
1688         if (args->mount_server.hostname)
1689                 request.hostname = args->mount_server.hostname;
1690         else
1691                 request.hostname = args->nfs_server.hostname;
1692
1693         /*
1694          * Construct the mount server's address.
1695          */
1696         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1697                 memcpy(request.sap, &args->nfs_server.address,
1698                        args->nfs_server.addrlen);
1699                 args->mount_server.addrlen = args->nfs_server.addrlen;
1700         }
1701         request.salen = args->mount_server.addrlen;
1702         nfs_set_port(request.sap, &args->mount_server.port, 0);
1703
1704         /*
1705          * Now ask the mount server to map our export path
1706          * to a file handle.
1707          */
1708         status = nfs_mount(&request);
1709         if (status != 0) {
1710                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1711                                 request.hostname, status);
1712                 return status;
1713         }
1714
1715         return 0;
1716 }
1717
1718 static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1719                                         struct nfs_subversion *nfs_mod)
1720 {
1721         int status;
1722         unsigned int i;
1723         bool tried_auth_unix = false;
1724         bool auth_null_in_list = false;
1725         struct nfs_server *server = ERR_PTR(-EACCES);
1726         struct nfs_parsed_mount_data *args = mount_info->parsed;
1727         rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1728         unsigned int authlist_len = ARRAY_SIZE(authlist);
1729
1730         status = nfs_request_mount(args, mount_info->mntfh, authlist,
1731                                         &authlist_len);
1732         if (status)
1733                 return ERR_PTR(status);
1734
1735         /*
1736          * Was a sec= authflavor specified in the options? First, verify
1737          * whether the server supports it, and then just try to use it if so.
1738          */
1739         if (args->auth_flavor_len > 0) {
1740                 status = nfs_verify_authflavor(args, authlist, authlist_len);
1741                 dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->auth_flavors[0]);
1742                 if (status)
1743                         return ERR_PTR(status);
1744                 return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1745         }
1746
1747         /*
1748          * No sec= option was provided. RFC 2623, section 2.7 suggests we
1749          * SHOULD prefer the flavor listed first. However, some servers list
1750          * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1751          */
1752         for (i = 0; i < authlist_len; ++i) {
1753                 rpc_authflavor_t flavor;
1754                 struct rpcsec_gss_info info;
1755
1756                 flavor = authlist[i];
1757                 switch (flavor) {
1758                 case RPC_AUTH_UNIX:
1759                         tried_auth_unix = true;
1760                         break;
1761                 case RPC_AUTH_NULL:
1762                         auth_null_in_list = true;
1763                         continue;
1764                 default:
1765                         if (rpcauth_get_gssinfo(flavor, &info) != 0)
1766                                 continue;
1767                         /* Fallthrough */
1768                 }
1769                 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1770                 nfs_set_auth_parsed_mount_data(args, flavor);
1771                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1772                 if (!IS_ERR(server))
1773                         return server;
1774         }
1775
1776         /*
1777          * Nothing we tried so far worked. At this point, give up if we've
1778          * already tried AUTH_UNIX or if the server's list doesn't contain
1779          * AUTH_NULL
1780          */
1781         if (tried_auth_unix || !auth_null_in_list)
1782                 return server;
1783
1784         /* Last chance! Try AUTH_UNIX */
1785         dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1786         nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
1787         return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1788 }
1789
1790 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1791                              struct nfs_mount_info *mount_info,
1792                              struct nfs_subversion *nfs_mod)
1793 {
1794         struct nfs_server *server;
1795
1796         if (mount_info->parsed->need_mount)
1797                 server = nfs_try_mount_request(mount_info, nfs_mod);
1798         else
1799                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1800
1801         if (IS_ERR(server))
1802                 return ERR_CAST(server);
1803
1804         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1805 }
1806 EXPORT_SYMBOL_GPL(nfs_try_mount);
1807
1808 /*
1809  * Split "dev_name" into "hostname:export_path".
1810  *
1811  * The leftmost colon demarks the split between the server's hostname
1812  * and the export path.  If the hostname starts with a left square
1813  * bracket, then it may contain colons.
1814  *
1815  * Note: caller frees hostname and export path, even on error.
1816  */
1817 static int nfs_parse_devname(const char *dev_name,
1818                              char **hostname, size_t maxnamlen,
1819                              char **export_path, size_t maxpathlen)
1820 {
1821         size_t len;
1822         char *end;
1823
1824         /* Is the host name protected with square brakcets? */
1825         if (*dev_name == '[') {
1826                 end = strchr(++dev_name, ']');
1827                 if (end == NULL || end[1] != ':')
1828                         goto out_bad_devname;
1829
1830                 len = end - dev_name;
1831                 end++;
1832         } else {
1833                 char *comma;
1834
1835                 end = strchr(dev_name, ':');
1836                 if (end == NULL)
1837                         goto out_bad_devname;
1838                 len = end - dev_name;
1839
1840                 /* kill possible hostname list: not supported */
1841                 comma = strchr(dev_name, ',');
1842                 if (comma != NULL && comma < end)
1843                         *comma = 0;
1844         }
1845
1846         if (len > maxnamlen)
1847                 goto out_hostname;
1848
1849         /* N.B. caller will free nfs_server.hostname in all cases */
1850         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1851         if (*hostname == NULL)
1852                 goto out_nomem;
1853         len = strlen(++end);
1854         if (len > maxpathlen)
1855                 goto out_path;
1856         *export_path = kstrndup(end, len, GFP_KERNEL);
1857         if (!*export_path)
1858                 goto out_nomem;
1859
1860         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1861         return 0;
1862
1863 out_bad_devname:
1864         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1865         return -EINVAL;
1866
1867 out_nomem:
1868         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1869         return -ENOMEM;
1870
1871 out_hostname:
1872         dfprintk(MOUNT, "NFS: server hostname too long\n");
1873         return -ENAMETOOLONG;
1874
1875 out_path:
1876         dfprintk(MOUNT, "NFS: export pathname too long\n");
1877         return -ENAMETOOLONG;
1878 }
1879
1880 /*
1881  * Validate the NFS2/NFS3 mount data
1882  * - fills in the mount root filehandle
1883  *
1884  * For option strings, user space handles the following behaviors:
1885  *
1886  * + DNS: mapping server host name to IP address ("addr=" option)
1887  *
1888  * + failure mode: how to behave if a mount request can't be handled
1889  *   immediately ("fg/bg" option)
1890  *
1891  * + retry: how often to retry a mount request ("retry=" option)
1892  *
1893  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1894  *   mountproto=tcp after mountproto=udp, and so on
1895  */
1896 static int nfs23_validate_mount_data(void *options,
1897                                      struct nfs_parsed_mount_data *args,
1898                                      struct nfs_fh *mntfh,
1899                                      const char *dev_name)
1900 {
1901         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1902         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1903         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1904
1905         if (data == NULL)
1906                 goto out_no_data;
1907
1908         args->version = NFS_DEFAULT_VERSION;
1909         switch (data->version) {
1910         case 1:
1911                 data->namlen = 0;
1912         case 2:
1913                 data->bsize = 0;
1914         case 3:
1915                 if (data->flags & NFS_MOUNT_VER3)
1916                         goto out_no_v3;
1917                 data->root.size = NFS2_FHSIZE;
1918                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1919                 /* Turn off security negotiation */
1920                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
1921         case 4:
1922                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1923                         goto out_no_sec;
1924         case 5:
1925                 memset(data->context, 0, sizeof(data->context));
1926         case 6:
1927                 if (data->flags & NFS_MOUNT_VER3) {
1928                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1929                                 goto out_invalid_fh;
1930                         mntfh->size = data->root.size;
1931                         args->version = 3;
1932                 } else {
1933                         mntfh->size = NFS2_FHSIZE;
1934                         args->version = 2;
1935                 }
1936
1937
1938                 memcpy(mntfh->data, data->root.data, mntfh->size);
1939                 if (mntfh->size < sizeof(mntfh->data))
1940                         memset(mntfh->data + mntfh->size, 0,
1941                                sizeof(mntfh->data) - mntfh->size);
1942
1943                 /*
1944                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
1945                  * can deal with.
1946                  */
1947                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1948                 args->flags             |= extra_flags;
1949                 args->rsize             = data->rsize;
1950                 args->wsize             = data->wsize;
1951                 args->timeo             = data->timeo;
1952                 args->retrans           = data->retrans;
1953                 args->acregmin          = data->acregmin;
1954                 args->acregmax          = data->acregmax;
1955                 args->acdirmin          = data->acdirmin;
1956                 args->acdirmax          = data->acdirmax;
1957                 args->need_mount        = false;
1958
1959                 memcpy(sap, &data->addr, sizeof(data->addr));
1960                 args->nfs_server.addrlen = sizeof(data->addr);
1961                 args->nfs_server.port = ntohs(data->addr.sin_port);
1962                 if (!nfs_verify_server_address(sap))
1963                         goto out_no_address;
1964
1965                 if (!(data->flags & NFS_MOUNT_TCP))
1966                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1967                 /* N.B. caller will free nfs_server.hostname in all cases */
1968                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1969                 args->namlen            = data->namlen;
1970                 args->bsize             = data->bsize;
1971
1972                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1973                         nfs_set_auth_parsed_mount_data(args, data->pseudoflavor);
1974                 else
1975                         nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
1976                 if (!args->nfs_server.hostname)
1977                         goto out_nomem;
1978
1979                 if (!(data->flags & NFS_MOUNT_NONLM))
1980                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1981                                          NFS_MOUNT_LOCAL_FCNTL);
1982                 else
1983                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1984                                         NFS_MOUNT_LOCAL_FCNTL);
1985                 /*
1986                  * The legacy version 6 binary mount data from userspace has a
1987                  * field used only to transport selinux information into the
1988                  * the kernel.  To continue to support that functionality we
1989                  * have a touch of selinux knowledge here in the NFS code. The
1990                  * userspace code converted context=blah to just blah so we are
1991                  * converting back to the full string selinux understands.
1992                  */
1993                 if (data->context[0]){
1994 #ifdef CONFIG_SECURITY_SELINUX
1995                         int rc;
1996                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1997                         if (!opts_str)
1998                                 return -ENOMEM;
1999                         strcpy(opts_str, "context=");
2000                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
2001                         strcat(opts_str, &data->context[0]);
2002                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
2003                         kfree(opts_str);
2004                         if (rc)
2005                                 return rc;
2006 #else
2007                         return -EINVAL;
2008 #endif
2009                 }
2010
2011                 break;
2012         default:
2013                 return NFS_TEXT_DATA;
2014         }
2015
2016 #if !IS_ENABLED(CONFIG_NFS_V3)
2017         if (args->version == 3)
2018                 goto out_v3_not_compiled;
2019 #endif /* !CONFIG_NFS_V3 */
2020
2021         return 0;
2022
2023 out_no_data:
2024         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2025         return -EINVAL;
2026
2027 out_no_v3:
2028         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2029                  data->version);
2030         return -EINVAL;
2031
2032 out_no_sec:
2033         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2034         return -EINVAL;
2035
2036 #if !IS_ENABLED(CONFIG_NFS_V3)
2037 out_v3_not_compiled:
2038         dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
2039         return -EPROTONOSUPPORT;
2040 #endif /* !CONFIG_NFS_V3 */
2041
2042 out_nomem:
2043         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2044         return -ENOMEM;
2045
2046 out_no_address:
2047         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2048         return -EINVAL;
2049
2050 out_invalid_fh:
2051         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2052         return -EINVAL;
2053 }
2054
2055 #if IS_ENABLED(CONFIG_NFS_V4)
2056 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2057                                    void *options,
2058                                    struct nfs_parsed_mount_data *args,
2059                                    struct nfs_fh *mntfh,
2060                                    const char *dev_name)
2061 {
2062         if (fs_type == &nfs_fs_type)
2063                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2064         return nfs4_validate_mount_data(options, args, dev_name);
2065 }
2066 #else
2067 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2068                                    void *options,
2069                                    struct nfs_parsed_mount_data *args,
2070                                    struct nfs_fh *mntfh,
2071                                    const char *dev_name)
2072 {
2073         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2074 }
2075 #endif
2076
2077 static int nfs_validate_text_mount_data(void *options,
2078                                         struct nfs_parsed_mount_data *args,
2079                                         const char *dev_name)
2080 {
2081         int port = 0;
2082         int max_namelen = PAGE_SIZE;
2083         int max_pathlen = NFS_MAXPATHLEN;
2084         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2085
2086         if (nfs_parse_mount_options((char *)options, args) == 0)
2087                 return -EINVAL;
2088
2089         if (!nfs_verify_server_address(sap))
2090                 goto out_no_address;
2091
2092         if (args->version == 4) {
2093 #if IS_ENABLED(CONFIG_NFS_V4)
2094                 port = NFS_PORT;
2095                 max_namelen = NFS4_MAXNAMLEN;
2096                 max_pathlen = NFS4_MAXPATHLEN;
2097                 nfs_validate_transport_protocol(args);
2098                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2099                         goto out_invalid_transport_udp;
2100                 nfs4_validate_mount_flags(args);
2101 #else
2102                 goto out_v4_not_compiled;
2103 #endif /* CONFIG_NFS_V4 */
2104         } else
2105                 nfs_set_mount_transport_protocol(args);
2106
2107         nfs_set_port(sap, &args->nfs_server.port, port);
2108
2109         if (args->auth_flavor_len > 1)
2110                 goto out_bad_auth;
2111
2112         return nfs_parse_devname(dev_name,
2113                                    &args->nfs_server.hostname,
2114                                    max_namelen,
2115                                    &args->nfs_server.export_path,
2116                                    max_pathlen);
2117
2118 #if !IS_ENABLED(CONFIG_NFS_V4)
2119 out_v4_not_compiled:
2120         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2121         return -EPROTONOSUPPORT;
2122 #else
2123 out_invalid_transport_udp:
2124         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2125         return -EINVAL;
2126 #endif /* !CONFIG_NFS_V4 */
2127
2128 out_no_address:
2129         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2130         return -EINVAL;
2131
2132 out_bad_auth:
2133         dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
2134         return -EINVAL;
2135 }
2136
2137 static int
2138 nfs_compare_remount_data(struct nfs_server *nfss,
2139                          struct nfs_parsed_mount_data *data)
2140 {
2141         if (data->flags != nfss->flags ||
2142             data->rsize != nfss->rsize ||
2143             data->wsize != nfss->wsize ||
2144             data->retrans != nfss->client->cl_timeout->to_retries ||
2145             data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2146             data->acregmin != nfss->acregmin / HZ ||
2147             data->acregmax != nfss->acregmax / HZ ||
2148             data->acdirmin != nfss->acdirmin / HZ ||
2149             data->acdirmax != nfss->acdirmax / HZ ||
2150             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2151             data->nfs_server.port != nfss->port ||
2152             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2153             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2154                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2155                 return -EINVAL;
2156
2157         return 0;
2158 }
2159
2160 int
2161 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2162 {
2163         int error;
2164         struct nfs_server *nfss = sb->s_fs_info;
2165         struct nfs_parsed_mount_data *data;
2166         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2167         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2168         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2169
2170         /*
2171          * Userspace mount programs that send binary options generally send
2172          * them populated with default values. We have no way to know which
2173          * ones were explicitly specified. Fall back to legacy behavior and
2174          * just return success.
2175          */
2176         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2177             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2178                                            options->version <= 6))))
2179                 return 0;
2180
2181         data = kzalloc(sizeof(*data), GFP_KERNEL);
2182         if (data == NULL)
2183                 return -ENOMEM;
2184
2185         /* fill out struct with values from existing mount */
2186         data->flags = nfss->flags;
2187         data->rsize = nfss->rsize;
2188         data->wsize = nfss->wsize;
2189         data->retrans = nfss->client->cl_timeout->to_retries;
2190         nfs_set_auth_parsed_mount_data(data, nfss->client->cl_auth->au_flavor);
2191         data->acregmin = nfss->acregmin / HZ;
2192         data->acregmax = nfss->acregmax / HZ;
2193         data->acdirmin = nfss->acdirmin / HZ;
2194         data->acdirmax = nfss->acdirmax / HZ;
2195         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2196         data->nfs_server.port = nfss->port;
2197         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2198         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2199                 data->nfs_server.addrlen);
2200
2201         /* overwrite those values with any that were specified */
2202         error = nfs_parse_mount_options((char *)options, data);
2203         if (error < 0)
2204                 goto out;
2205
2206         /*
2207          * noac is a special case. It implies -o sync, but that's not
2208          * necessarily reflected in the mtab options. do_remount_sb
2209          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2210          * remount options, so we have to explicitly reset it.
2211          */
2212         if (data->flags & NFS_MOUNT_NOAC)
2213                 *flags |= MS_SYNCHRONOUS;
2214
2215         /* compare new mount options with old ones */
2216         error = nfs_compare_remount_data(nfss, data);
2217 out:
2218         kfree(data);
2219         return error;
2220 }
2221 EXPORT_SYMBOL_GPL(nfs_remount);
2222
2223 /*
2224  * Initialise the common bits of the superblock
2225  */
2226 inline void nfs_initialise_sb(struct super_block *sb)
2227 {
2228         struct nfs_server *server = NFS_SB(sb);
2229
2230         sb->s_magic = NFS_SUPER_MAGIC;
2231
2232         /* We probably want something more informative here */
2233         snprintf(sb->s_id, sizeof(sb->s_id),
2234                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2235
2236         if (sb->s_blocksize == 0)
2237                 sb->s_blocksize = nfs_block_bits(server->wsize,
2238                                                  &sb->s_blocksize_bits);
2239
2240         sb->s_bdi = &server->backing_dev_info;
2241
2242         nfs_super_set_maxbytes(sb, server->maxfilesize);
2243 }
2244
2245 /*
2246  * Finish setting up an NFS2/3 superblock
2247  */
2248 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2249 {
2250         struct nfs_parsed_mount_data *data = mount_info->parsed;
2251         struct nfs_server *server = NFS_SB(sb);
2252
2253         sb->s_blocksize_bits = 0;
2254         sb->s_blocksize = 0;
2255         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2256         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2257         if (data && data->bsize)
2258                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2259
2260         if (server->nfs_client->rpc_ops->version != 2) {
2261                 /* The VFS shouldn't apply the umask to mode bits. We will do
2262                  * so ourselves when necessary.
2263                  */
2264                 sb->s_flags |= MS_POSIXACL;
2265                 sb->s_time_gran = 1;
2266         }
2267
2268         nfs_initialise_sb(sb);
2269 }
2270 EXPORT_SYMBOL_GPL(nfs_fill_super);
2271
2272 /*
2273  * Finish setting up a cloned NFS2/3/4 superblock
2274  */
2275 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2276 {
2277         const struct super_block *old_sb = mount_info->cloned->sb;
2278         struct nfs_server *server = NFS_SB(sb);
2279
2280         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2281         sb->s_blocksize = old_sb->s_blocksize;
2282         sb->s_maxbytes = old_sb->s_maxbytes;
2283         sb->s_xattr = old_sb->s_xattr;
2284         sb->s_op = old_sb->s_op;
2285         sb->s_time_gran = 1;
2286
2287         if (server->nfs_client->rpc_ops->version != 2) {
2288                 /* The VFS shouldn't apply the umask to mode bits. We will do
2289                  * so ourselves when necessary.
2290                  */
2291                 sb->s_flags |= MS_POSIXACL;
2292         }
2293
2294         nfs_initialise_sb(sb);
2295 }
2296
2297 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2298 {
2299         const struct nfs_server *a = s->s_fs_info;
2300         const struct rpc_clnt *clnt_a = a->client;
2301         const struct rpc_clnt *clnt_b = b->client;
2302
2303         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2304                 goto Ebusy;
2305         if (a->nfs_client != b->nfs_client)
2306                 goto Ebusy;
2307         if (a->flags != b->flags)
2308                 goto Ebusy;
2309         if (a->wsize != b->wsize)
2310                 goto Ebusy;
2311         if (a->rsize != b->rsize)
2312                 goto Ebusy;
2313         if (a->acregmin != b->acregmin)
2314                 goto Ebusy;
2315         if (a->acregmax != b->acregmax)
2316                 goto Ebusy;
2317         if (a->acdirmin != b->acdirmin)
2318                 goto Ebusy;
2319         if (a->acdirmax != b->acdirmax)
2320                 goto Ebusy;
2321         if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2322                 goto Ebusy;
2323         return 1;
2324 Ebusy:
2325         return 0;
2326 }
2327
2328 struct nfs_sb_mountdata {
2329         struct nfs_server *server;
2330         int mntflags;
2331 };
2332
2333 static int nfs_set_super(struct super_block *s, void *data)
2334 {
2335         struct nfs_sb_mountdata *sb_mntdata = data;
2336         struct nfs_server *server = sb_mntdata->server;
2337         int ret;
2338
2339         s->s_flags = sb_mntdata->mntflags;
2340         s->s_fs_info = server;
2341         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2342         ret = set_anon_super(s, server);
2343         if (ret == 0)
2344                 server->s_dev = s->s_dev;
2345         return ret;
2346 }
2347
2348 static int nfs_compare_super_address(struct nfs_server *server1,
2349                                      struct nfs_server *server2)
2350 {
2351         struct sockaddr *sap1, *sap2;
2352
2353         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2354         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2355
2356         if (sap1->sa_family != sap2->sa_family)
2357                 return 0;
2358
2359         switch (sap1->sa_family) {
2360         case AF_INET: {
2361                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2362                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2363                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2364                         return 0;
2365                 if (sin1->sin_port != sin2->sin_port)
2366                         return 0;
2367                 break;
2368         }
2369         case AF_INET6: {
2370                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2371                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2372                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2373                         return 0;
2374                 if (sin1->sin6_port != sin2->sin6_port)
2375                         return 0;
2376                 break;
2377         }
2378         default:
2379                 return 0;
2380         }
2381
2382         return 1;
2383 }
2384
2385 static int nfs_compare_super(struct super_block *sb, void *data)
2386 {
2387         struct nfs_sb_mountdata *sb_mntdata = data;
2388         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2389         int mntflags = sb_mntdata->mntflags;
2390
2391         if (!nfs_compare_super_address(old, server))
2392                 return 0;
2393         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2394         if (old->flags & NFS_MOUNT_UNSHARED)
2395                 return 0;
2396         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2397                 return 0;
2398         return nfs_compare_mount_options(sb, server, mntflags);
2399 }
2400
2401 #ifdef CONFIG_NFS_FSCACHE
2402 static void nfs_get_cache_cookie(struct super_block *sb,
2403                                  struct nfs_parsed_mount_data *parsed,
2404                                  struct nfs_clone_mount *cloned)
2405 {
2406         struct nfs_server *nfss = NFS_SB(sb);
2407         char *uniq = NULL;
2408         int ulen = 0;
2409
2410         nfss->fscache_key = NULL;
2411         nfss->fscache = NULL;
2412
2413         if (parsed) {
2414                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2415                         return;
2416                 if (parsed->fscache_uniq) {
2417                         uniq = parsed->fscache_uniq;
2418                         ulen = strlen(parsed->fscache_uniq);
2419                 }
2420         } else if (cloned) {
2421                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2422                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2423                         return;
2424                 if (mnt_s->fscache_key) {
2425                         uniq = mnt_s->fscache_key->key.uniquifier;
2426                         ulen = mnt_s->fscache_key->key.uniq_len;
2427                 };
2428         } else
2429                 return;
2430
2431         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2432 }
2433 #else
2434 static void nfs_get_cache_cookie(struct super_block *sb,
2435                                  struct nfs_parsed_mount_data *parsed,
2436                                  struct nfs_clone_mount *cloned)
2437 {
2438 }
2439 #endif
2440
2441 static int nfs_bdi_register(struct nfs_server *server)
2442 {
2443         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2444 }
2445
2446 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2447                         struct nfs_mount_info *mount_info)
2448 {
2449         int error;
2450         unsigned long kflags = 0, kflags_out = 0;
2451         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2452                 kflags |= SECURITY_LSM_NATIVE_LABELS;
2453
2454         error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
2455                                                 kflags, &kflags_out);
2456         if (error)
2457                 goto err;
2458
2459         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2460                 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2461                 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2462 err:
2463         return error;
2464 }
2465 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2466
2467 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2468                           struct nfs_mount_info *mount_info)
2469 {
2470         /* clone any lsm security options from the parent to the new sb */
2471         if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2472                 return -ESTALE;
2473         return security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2474 }
2475 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2476
2477 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2478                                    int flags, const char *dev_name,
2479                                    struct nfs_mount_info *mount_info,
2480                                    struct nfs_subversion *nfs_mod)
2481 {
2482         struct super_block *s;
2483         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2484         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2485         struct nfs_sb_mountdata sb_mntdata = {
2486                 .mntflags = flags,
2487                 .server = server,
2488         };
2489         int error;
2490
2491         if (server->flags & NFS_MOUNT_UNSHARED)
2492                 compare_super = NULL;
2493
2494         /* -o noac implies -o sync */
2495         if (server->flags & NFS_MOUNT_NOAC)
2496                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2497
2498         /* Get a superblock - note that we may end up sharing one that already exists */
2499         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2500         if (IS_ERR(s)) {
2501                 mntroot = ERR_CAST(s);
2502                 goto out_err_nosb;
2503         }
2504
2505         if (s->s_fs_info != server) {
2506                 nfs_free_server(server);
2507                 server = NULL;
2508         } else {
2509                 error = nfs_bdi_register(server);
2510                 if (error) {
2511                         mntroot = ERR_PTR(error);
2512                         goto error_splat_bdi;
2513                 }
2514         }
2515
2516         if (!s->s_root) {
2517                 /* initial superblock/root creation */
2518                 mount_info->fill_super(s, mount_info);
2519                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2520         }
2521
2522         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2523         if (IS_ERR(mntroot))
2524                 goto error_splat_super;
2525
2526         error = mount_info->set_security(s, mntroot, mount_info);
2527         if (error)
2528                 goto error_splat_root;
2529
2530         s->s_flags |= MS_ACTIVE;
2531
2532 out:
2533         return mntroot;
2534
2535 out_err_nosb:
2536         nfs_free_server(server);
2537         goto out;
2538
2539 error_splat_root:
2540         dput(mntroot);
2541         mntroot = ERR_PTR(error);
2542 error_splat_super:
2543         if (server && !s->s_root)
2544                 bdi_unregister(&server->backing_dev_info);
2545 error_splat_bdi:
2546         deactivate_locked_super(s);
2547         goto out;
2548 }
2549 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2550
2551 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2552         int flags, const char *dev_name, void *raw_data)
2553 {
2554         struct nfs_mount_info mount_info = {
2555                 .fill_super = nfs_fill_super,
2556                 .set_security = nfs_set_sb_security,
2557         };
2558         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2559         struct nfs_subversion *nfs_mod;
2560         int error;
2561
2562         mount_info.parsed = nfs_alloc_parsed_mount_data();
2563         mount_info.mntfh = nfs_alloc_fhandle();
2564         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2565                 goto out;
2566
2567         /* Validate the mount data */
2568         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2569         if (error == NFS_TEXT_DATA)
2570                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2571         if (error < 0) {
2572                 mntroot = ERR_PTR(error);
2573                 goto out;
2574         }
2575
2576         nfs_mod = get_nfs_version(mount_info.parsed->version);
2577         if (IS_ERR(nfs_mod)) {
2578                 mntroot = ERR_CAST(nfs_mod);
2579                 goto out;
2580         }
2581
2582         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2583
2584         put_nfs_version(nfs_mod);
2585 out:
2586         nfs_free_parsed_mount_data(mount_info.parsed);
2587         nfs_free_fhandle(mount_info.mntfh);
2588         return mntroot;
2589 }
2590 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2591
2592 /*
2593  * Ensure that we unregister the bdi before kill_anon_super
2594  * releases the device name
2595  */
2596 void nfs_put_super(struct super_block *s)
2597 {
2598         struct nfs_server *server = NFS_SB(s);
2599
2600         bdi_unregister(&server->backing_dev_info);
2601 }
2602 EXPORT_SYMBOL_GPL(nfs_put_super);
2603
2604 /*
2605  * Destroy an NFS2/3 superblock
2606  */
2607 void nfs_kill_super(struct super_block *s)
2608 {
2609         struct nfs_server *server = NFS_SB(s);
2610
2611         kill_anon_super(s);
2612         nfs_fscache_release_super_cookie(s);
2613         nfs_free_server(server);
2614 }
2615 EXPORT_SYMBOL_GPL(nfs_kill_super);
2616
2617 /*
2618  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2619  */
2620 static struct dentry *
2621 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2622                 const char *dev_name, void *raw_data)
2623 {
2624         struct nfs_clone_mount *data = raw_data;
2625         struct nfs_mount_info mount_info = {
2626                 .fill_super = nfs_clone_super,
2627                 .set_security = nfs_clone_sb_security,
2628                 .cloned = data,
2629         };
2630         struct nfs_server *server;
2631         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2632         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2633
2634         dprintk("--> nfs_xdev_mount()\n");
2635
2636         mount_info.mntfh = mount_info.cloned->fh;
2637
2638         /* create a new volume representation */
2639         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2640
2641         if (IS_ERR(server))
2642                 mntroot = ERR_CAST(server);
2643         else
2644                 mntroot = nfs_fs_mount_common(server, flags,
2645                                 dev_name, &mount_info, nfs_mod);
2646
2647         dprintk("<-- nfs_xdev_mount() = %ld\n",
2648                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2649         return mntroot;
2650 }
2651
2652 #if IS_ENABLED(CONFIG_NFS_V4)
2653
2654 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2655 {
2656         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2657                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2658 }
2659
2660 /*
2661  * Validate NFSv4 mount options
2662  */
2663 static int nfs4_validate_mount_data(void *options,
2664                                     struct nfs_parsed_mount_data *args,
2665                                     const char *dev_name)
2666 {
2667         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2668         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2669         char *c;
2670
2671         if (data == NULL)
2672                 goto out_no_data;
2673
2674         args->version = 4;
2675
2676         switch (data->version) {
2677         case 1:
2678                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2679                         goto out_no_address;
2680                 if (data->host_addrlen == 0)
2681                         goto out_no_address;
2682                 args->nfs_server.addrlen = data->host_addrlen;
2683                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2684                         return -EFAULT;
2685                 if (!nfs_verify_server_address(sap))
2686                         goto out_no_address;
2687                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2688
2689                 if (data->auth_flavourlen) {
2690                         rpc_authflavor_t pseudoflavor;
2691                         if (data->auth_flavourlen > 1)
2692                                 goto out_inval_auth;
2693                         if (copy_from_user(&pseudoflavor,
2694                                            data->auth_flavours,
2695                                            sizeof(pseudoflavor)))
2696                                 return -EFAULT;
2697                         nfs_set_auth_parsed_mount_data(args, pseudoflavor);
2698                 } else
2699                         nfs_set_auth_parsed_mount_data(args, RPC_AUTH_UNIX);
2700
2701                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2702                 if (IS_ERR(c))
2703                         return PTR_ERR(c);
2704                 args->nfs_server.hostname = c;
2705
2706                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2707                 if (IS_ERR(c))
2708                         return PTR_ERR(c);
2709                 args->nfs_server.export_path = c;
2710                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2711
2712                 c = strndup_user(data->client_addr.data, 16);
2713                 if (IS_ERR(c))
2714                         return PTR_ERR(c);
2715                 args->client_address = c;
2716
2717                 /*
2718                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2719                  * can deal with.
2720                  */
2721
2722                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2723                 args->rsize     = data->rsize;
2724                 args->wsize     = data->wsize;
2725                 args->timeo     = data->timeo;
2726                 args->retrans   = data->retrans;
2727                 args->acregmin  = data->acregmin;
2728                 args->acregmax  = data->acregmax;
2729                 args->acdirmin  = data->acdirmin;
2730                 args->acdirmax  = data->acdirmax;
2731                 args->nfs_server.protocol = data->proto;
2732                 nfs_validate_transport_protocol(args);
2733                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2734                         goto out_invalid_transport_udp;
2735
2736                 break;
2737         default:
2738                 return NFS_TEXT_DATA;
2739         }
2740
2741         return 0;
2742
2743 out_no_data:
2744         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2745         return -EINVAL;
2746
2747 out_inval_auth:
2748         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2749                  data->auth_flavourlen);
2750         return -EINVAL;
2751
2752 out_no_address:
2753         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2754         return -EINVAL;
2755
2756 out_invalid_transport_udp:
2757         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2758         return -EINVAL;
2759 }
2760
2761 /*
2762  * NFS v4 module parameters need to stay in the
2763  * NFS client for backwards compatibility
2764  */
2765 unsigned int nfs_callback_set_tcpport;
2766 unsigned short nfs_callback_tcpport;
2767 /* Default cache timeout is 10 minutes */
2768 unsigned int nfs_idmap_cache_timeout = 600;
2769 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2770 bool nfs4_disable_idmapping = true;
2771 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2772 unsigned short send_implementation_id = 1;
2773 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2774 bool recover_lost_locks = false;
2775
2776 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2777 EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2778 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2779 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2780 EXPORT_SYMBOL_GPL(max_session_slots);
2781 EXPORT_SYMBOL_GPL(send_implementation_id);
2782 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2783 EXPORT_SYMBOL_GPL(recover_lost_locks);
2784
2785 #define NFS_CALLBACK_MAXPORTNR (65535U)
2786
2787 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2788 {
2789         unsigned long num;
2790         int ret;
2791
2792         if (!val)
2793                 return -EINVAL;
2794         ret = kstrtoul(val, 0, &num);
2795         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2796                 return -EINVAL;
2797         *((unsigned int *)kp->arg) = num;
2798         return 0;
2799 }
2800 static struct kernel_param_ops param_ops_portnr = {
2801         .set = param_set_portnr,
2802         .get = param_get_uint,
2803 };
2804 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2805
2806 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2807 module_param(nfs_idmap_cache_timeout, int, 0644);
2808 module_param(nfs4_disable_idmapping, bool, 0644);
2809 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2810                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2811 MODULE_PARM_DESC(nfs4_disable_idmapping,
2812                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2813 module_param(max_session_slots, ushort, 0644);
2814 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2815                 "requests the client will negotiate");
2816 module_param(send_implementation_id, ushort, 0644);
2817 MODULE_PARM_DESC(send_implementation_id,
2818                 "Send implementation ID with NFSv4.1 exchange_id");
2819 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2820
2821 module_param(recover_lost_locks, bool, 0644);
2822 MODULE_PARM_DESC(recover_lost_locks,
2823                  "If the server reports that a lock might be lost, "
2824                  "try to recover it risking data corruption.");
2825
2826
2827 #endif /* CONFIG_NFS_V4 */