kernel/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/vfs.h>
  47 #include <linux/inet.h>
  48 #include <linux/in6.h>
  49 #include <linux/slab.h>
  50 #include <net/ipv6.h>
  51 #include <linux/netdevice.h>
  52 #include <linux/nfs_xdr.h>
  53 #include <linux/magic.h>
  54 #include <linux/parser.h>
  55 #include <linux/nsproxy.h>
  56 #include <linux/rcupdate.h>
  57
  58 #include <asm/uaccess.h>
  59
  60 #include "nfs4_fs.h"
  61 #include "callback.h"
  62 #include "delegation.h"
  63 #include "iostat.h"
  64 #include "internal.h"
  65 #include "fscache.h"
  66 #include "nfs4session.h"
  67 #include "pnfs.h"
  68 #include "nfs.h"
  69
  70 #define NFSDBG_FACILITY         NFSDBG_VFS
  71 #define NFS_TEXT_DATA           1
  72
  73 #if IS_ENABLED(CONFIG_NFS_V3)
  74 #define NFS_DEFAULT_VERSION 3
  75 #else
  76 #define NFS_DEFAULT_VERSION 2
  77 #endif
  78
  79 enum {
  80         /* Mount options that take no arguments */
  81         Opt_soft, Opt_hard,
  82         Opt_posix, Opt_noposix,
  83         Opt_cto, Opt_nocto,
  84         Opt_ac, Opt_noac,
  85         Opt_lock, Opt_nolock,
  86         Opt_udp, Opt_tcp, Opt_rdma,
  87         Opt_acl, Opt_noacl,
  88         Opt_rdirplus, Opt_nordirplus,
  89         Opt_sharecache, Opt_nosharecache,
  90         Opt_resvport, Opt_noresvport,
  91         Opt_fscache, Opt_nofscache,
  92         Opt_migration, Opt_nomigration,
  93
  94         /* Mount options that take integer arguments */
  95         Opt_port,
  96         Opt_rsize, Opt_wsize, Opt_bsize,
  97         Opt_timeo, Opt_retrans,
  98         Opt_acregmin, Opt_acregmax,
  99         Opt_acdirmin, Opt_acdirmax,
 100         Opt_actimeo,
 101         Opt_namelen,
 102         Opt_mountport,
 103         Opt_mountvers,
 104         Opt_minorversion,
 105
 106         /* Mount options that take string arguments */
 107         Opt_nfsvers,
 108         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
 109         Opt_addr, Opt_mountaddr, Opt_clientaddr,
 110         Opt_lookupcache,
 111         Opt_fscache_uniq,
 112         Opt_local_lock,
 113
 114         /* Special mount options */
 115         Opt_userspace, Opt_deprecated, Opt_sloppy,
 116
 117         Opt_err
 118 };
 119
 120 static const match_table_t nfs_mount_option_tokens = {
 121         { Opt_userspace, "bg" },
 122         { Opt_userspace, "fg" },
 123         { Opt_userspace, "retry=%s" },
 124
 125         { Opt_sloppy, "sloppy" },
 126
 127         { Opt_soft, "soft" },
 128         { Opt_hard, "hard" },
 129         { Opt_deprecated, "intr" },
 130         { Opt_deprecated, "nointr" },
 131         { Opt_posix, "posix" },
 132         { Opt_noposix, "noposix" },
 133         { Opt_cto, "cto" },
 134         { Opt_nocto, "nocto" },
 135         { Opt_ac, "ac" },
 136         { Opt_noac, "noac" },
 137         { Opt_lock, "lock" },
 138         { Opt_nolock, "nolock" },
 139         { Opt_udp, "udp" },
 140         { Opt_tcp, "tcp" },
 141         { Opt_rdma, "rdma" },
 142         { Opt_acl, "acl" },
 143         { Opt_noacl, "noacl" },
 144         { Opt_rdirplus, "rdirplus" },
 145         { Opt_nordirplus, "nordirplus" },
 146         { Opt_sharecache, "sharecache" },
 147         { Opt_nosharecache, "nosharecache" },
 148         { Opt_resvport, "resvport" },
 149         { Opt_noresvport, "noresvport" },
 150         { Opt_fscache, "fsc" },
 151         { Opt_nofscache, "nofsc" },
 152         { Opt_migration, "migration" },
 153         { Opt_nomigration, "nomigration" },
 154
 155         { Opt_port, "port=%s" },
 156         { Opt_rsize, "rsize=%s" },
 157         { Opt_wsize, "wsize=%s" },
 158         { Opt_bsize, "bsize=%s" },
 159         { Opt_timeo, "timeo=%s" },
 160         { Opt_retrans, "retrans=%s" },
 161         { Opt_acregmin, "acregmin=%s" },
 162         { Opt_acregmax, "acregmax=%s" },
 163         { Opt_acdirmin, "acdirmin=%s" },
 164         { Opt_acdirmax, "acdirmax=%s" },
 165         { Opt_actimeo, "actimeo=%s" },
 166         { Opt_namelen, "namlen=%s" },
 167         { Opt_mountport, "mountport=%s" },
 168         { Opt_mountvers, "mountvers=%s" },
 169         { Opt_minorversion, "minorversion=%s" },
 170
 171         { Opt_nfsvers, "nfsvers=%s" },
 172         { Opt_nfsvers, "vers=%s" },
 173
 174         { Opt_sec, "sec=%s" },
 175         { Opt_proto, "proto=%s" },
 176         { Opt_mountproto, "mountproto=%s" },
 177         { Opt_addr, "addr=%s" },
 178         { Opt_clientaddr, "clientaddr=%s" },
 179         { Opt_mounthost, "mounthost=%s" },
 180         { Opt_mountaddr, "mountaddr=%s" },
 181
 182         { Opt_lookupcache, "lookupcache=%s" },
 183         { Opt_fscache_uniq, "fsc=%s" },
 184         { Opt_local_lock, "local_lock=%s" },
 185
 186         /* The following needs to be listed after all other options */
 187         { Opt_nfsvers, "v%s" },
 188
 189         { Opt_err, NULL }
 190 };
 191
 192 enum {
 193         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 194
 195         Opt_xprt_err
 196 };
 197
 198 static const match_table_t nfs_xprt_protocol_tokens = {
 199         { Opt_xprt_udp, "udp" },
 200         { Opt_xprt_udp6, "udp6" },
 201         { Opt_xprt_tcp, "tcp" },
 202         { Opt_xprt_tcp6, "tcp6" },
 203         { Opt_xprt_rdma, "rdma" },
 204
 205         { Opt_xprt_err, NULL }
 206 };
 207
 208 enum {
 209         Opt_sec_none, Opt_sec_sys,
 210         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 211         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 212         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 213
 214         Opt_sec_err
 215 };
 216
 217 static const match_table_t nfs_secflavor_tokens = {
 218         { Opt_sec_none, "none" },
 219         { Opt_sec_none, "null" },
 220         { Opt_sec_sys, "sys" },
 221
 222         { Opt_sec_krb5, "krb5" },
 223         { Opt_sec_krb5i, "krb5i" },
 224         { Opt_sec_krb5p, "krb5p" },
 225
 226         { Opt_sec_lkey, "lkey" },
 227         { Opt_sec_lkeyi, "lkeyi" },
 228         { Opt_sec_lkeyp, "lkeyp" },
 229
 230         { Opt_sec_spkm, "spkm3" },
 231         { Opt_sec_spkmi, "spkm3i" },
 232         { Opt_sec_spkmp, "spkm3p" },
 233
 234         { Opt_sec_err, NULL }
 235 };
 236
 237 enum {
 238         Opt_lookupcache_all, Opt_lookupcache_positive,
 239         Opt_lookupcache_none,
 240
 241         Opt_lookupcache_err
 242 };
 243
 244 static match_table_t nfs_lookupcache_tokens = {
 245         { Opt_lookupcache_all, "all" },
 246         { Opt_lookupcache_positive, "pos" },
 247         { Opt_lookupcache_positive, "positive" },
 248         { Opt_lookupcache_none, "none" },
 249
 250         { Opt_lookupcache_err, NULL }
 251 };
 252
 253 enum {
 254         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 255         Opt_local_lock_none,
 256
 257         Opt_local_lock_err
 258 };
 259
 260 static match_table_t nfs_local_lock_tokens = {
 261         { Opt_local_lock_all, "all" },
 262         { Opt_local_lock_flock, "flock" },
 263         { Opt_local_lock_posix, "posix" },
 264         { Opt_local_lock_none, "none" },
 265
 266         { Opt_local_lock_err, NULL }
 267 };
 268
 269 enum {
 270         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 271         Opt_vers_4_1, Opt_vers_4_2,
 272
 273         Opt_vers_err
 274 };
 275
 276 static match_table_t nfs_vers_tokens = {
 277         { Opt_vers_2, "2" },
 278         { Opt_vers_3, "3" },
 279         { Opt_vers_4, "4" },
 280         { Opt_vers_4_0, "4.0" },
 281         { Opt_vers_4_1, "4.1" },
 282         { Opt_vers_4_2, "4.2" },
 283
 284         { Opt_vers_err, NULL }
 285 };
 286
 287 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 288                 int flags, const char *dev_name, void *raw_data);
 289
 290 struct file_system_type nfs_fs_type = {
 291         .owner          = THIS_MODULE,
 292         .name           = "nfs",
 293         .mount          = nfs_fs_mount,
 294         .kill_sb        = nfs_kill_super,
 295         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 296 };
 297 MODULE_ALIAS_FS("nfs");
 298 EXPORT_SYMBOL_GPL(nfs_fs_type);
 299
 300 struct file_system_type nfs_xdev_fs_type = {
 301         .owner          = THIS_MODULE,
 302         .name           = "nfs",
 303         .mount          = nfs_xdev_mount,
 304         .kill_sb        = nfs_kill_super,
 305         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 306 };
 307
 308 const struct super_operations nfs_sops = {
 309         .alloc_inode    = nfs_alloc_inode,
 310         .destroy_inode  = nfs_destroy_inode,
 311         .write_inode    = nfs_write_inode,
 312         .drop_inode     = nfs_drop_inode,
 313         .statfs         = nfs_statfs,
 314         .evict_inode    = nfs_evict_inode,
 315         .umount_begin   = nfs_umount_begin,
 316         .show_options   = nfs_show_options,
 317         .show_devname   = nfs_show_devname,
 318         .show_path      = nfs_show_path,
 319         .show_stats     = nfs_show_stats,
 320         .remount_fs     = nfs_remount,
 321 };
 322 EXPORT_SYMBOL_GPL(nfs_sops);
 323
 324 #if IS_ENABLED(CONFIG_NFS_V4)
 325 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 326 static int nfs4_validate_mount_data(void *options,
 327         struct nfs_parsed_mount_data *args, const char *dev_name);
 328
 329 struct file_system_type nfs4_fs_type = {
 330         .owner          = THIS_MODULE,
 331         .name           = "nfs4",
 332         .mount          = nfs_fs_mount,
 333         .kill_sb        = nfs_kill_super,
 334         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 335 };
 336 MODULE_ALIAS_FS("nfs4");
 337 MODULE_ALIAS("nfs4");
 338 EXPORT_SYMBOL_GPL(nfs4_fs_type);
 339
 340 static int __init register_nfs4_fs(void)
 341 {
 342         return register_filesystem(&nfs4_fs_type);
 343 }
 344
 345 static void unregister_nfs4_fs(void)
 346 {
 347         unregister_filesystem(&nfs4_fs_type);
 348 }
 349 #else
 350 static int __init register_nfs4_fs(void)
 351 {
 352         return 0;
 353 }
 354
 355 static void unregister_nfs4_fs(void)
 356 {
 357 }
 358 #endif
 359
 360 static struct shrinker acl_shrinker = {
 361         .count_objects  = nfs_access_cache_count,
 362         .scan_objects   = nfs_access_cache_scan,
 363         .seeks          = DEFAULT_SEEKS,
 364 };
 365
 366 /*
 367  * Register the NFS filesystems
 368  */
 369 int __init register_nfs_fs(void)
 370 {
 371         int ret;
 372
 373         ret = register_filesystem(&nfs_fs_type);
 374         if (ret < 0)
 375                 goto error_0;
 376
 377         ret = register_nfs4_fs();
 378         if (ret < 0)
 379                 goto error_1;
 380
 381         ret = nfs_register_sysctl();
 382         if (ret < 0)
 383                 goto error_2;
 384         ret = register_shrinker(&acl_shrinker);
 385         if (ret < 0)
 386                 goto error_3;
 387         return 0;
 388 error_3:
 389         nfs_unregister_sysctl();
 390 error_2:
 391         unregister_nfs4_fs();
 392 error_1:
 393         unregister_filesystem(&nfs_fs_type);
 394 error_0:
 395         return ret;
 396 }
 397
 398 /*
 399  * Unregister the NFS filesystems
 400  */
 401 void __exit unregister_nfs_fs(void)
 402 {
 403         unregister_shrinker(&acl_shrinker);
 404         nfs_unregister_sysctl();
 405         unregister_nfs4_fs();
 406         unregister_filesystem(&nfs_fs_type);
 407 }
 408
 409 bool nfs_sb_active(struct super_block *sb)
 410 {
 411         struct nfs_server *server = NFS_SB(sb);
 412
 413         if (!atomic_inc_not_zero(&sb->s_active))
 414                 return false;
 415         if (atomic_inc_return(&server->active) != 1)
 416                 atomic_dec(&sb->s_active);
 417         return true;
 418 }
 419 EXPORT_SYMBOL_GPL(nfs_sb_active);
 420
 421 void nfs_sb_deactive(struct super_block *sb)
 422 {
 423         struct nfs_server *server = NFS_SB(sb);
 424
 425         if (atomic_dec_and_test(&server->active))
 426                 deactivate_super(sb);
 427 }
 428 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 429
 430 /*
 431  * Deliver file system statistics to userspace
 432  */
 433 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 434 {
 435         struct nfs_server *server = NFS_SB(dentry->d_sb);
 436         unsigned char blockbits;
 437         unsigned long blockres;
 438         struct nfs_fh *fh = NFS_FH(d_inode(dentry));
 439         struct nfs_fsstat res;
 440         int error = -ENOMEM;
 441
 442         res.fattr = nfs_alloc_fattr();
 443         if (res.fattr == NULL)
 444                 goto out_err;
 445
 446         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 447         if (unlikely(error == -ESTALE)) {
 448                 struct dentry *pd_dentry;
 449
 450                 pd_dentry = dget_parent(dentry);
 451                 if (pd_dentry != NULL) {
 452                         nfs_zap_caches(d_inode(pd_dentry));
 453                         dput(pd_dentry);
 454                 }
 455         }
 456         nfs_free_fattr(res.fattr);
 457         if (error < 0)
 458                 goto out_err;
 459
 460         buf->f_type = NFS_SUPER_MAGIC;
 461
 462         /*
 463          * Current versions of glibc do not correctly handle the
 464          * case where f_frsize != f_bsize.  Eventually we want to
 465          * report the value of wtmult in this field.
 466          */
 467         buf->f_frsize = dentry->d_sb->s_blocksize;
 468
 469         /*
 470          * On most *nix systems, f_blocks, f_bfree, and f_bavail
 471          * are reported in units of f_frsize.  Linux hasn't had
 472          * an f_frsize field in its statfs struct until recently,
 473          * thus historically Linux's sys_statfs reports these
 474          * fields in units of f_bsize.
 475          */
 476         buf->f_bsize = dentry->d_sb->s_blocksize;
 477         blockbits = dentry->d_sb->s_blocksize_bits;
 478         blockres = (1 << blockbits) - 1;
 479         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 480         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 481         buf->f_bavail = (res.abytes + blockres) >> blockbits;
 482
 483         buf->f_files = res.tfiles;
 484         buf->f_ffree = res.afiles;
 485
 486         buf->f_namelen = server->namelen;
 487
 488         return 0;
 489
 490  out_err:
 491         dprintk("%s: statfs error = %d\n", __func__, -error);
 492         return error;
 493 }
 494 EXPORT_SYMBOL_GPL(nfs_statfs);
 495
 496 /*
 497  * Map the security flavour number to a name
 498  */
 499 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 500 {
 501         static const struct {
 502                 rpc_authflavor_t flavour;
 503                 const char *str;
 504         } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
 505                 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
 506                 { RPC_AUTH_NULL, "null" },
 507                 { RPC_AUTH_UNIX, "sys" },
 508                 { RPC_AUTH_GSS_KRB5, "krb5" },
 509                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
 510                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
 511                 { RPC_AUTH_GSS_LKEY, "lkey" },
 512                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 513                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 514                 { RPC_AUTH_GSS_SPKM, "spkm" },
 515                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
 516                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
 517                 { UINT_MAX, "unknown" }
 518         };
 519         int i;
 520
 521         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 522                 if (sec_flavours[i].flavour == flavour)
 523                         break;
 524         }
 525         return sec_flavours[i].str;
 526 }
 527
 528 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 529                                   int showdefaults)
 530 {
 531         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 532
 533         seq_printf(m, ",mountproto=");
 534         switch (sap->sa_family) {
 535         case AF_INET:
 536                 switch (nfss->mountd_protocol) {
 537                 case IPPROTO_UDP:
 538                         seq_printf(m, RPCBIND_NETID_UDP);
 539                         break;
 540                 case IPPROTO_TCP:
 541                         seq_printf(m, RPCBIND_NETID_TCP);
 542                         break;
 543                 default:
 544                         if (showdefaults)
 545                                 seq_printf(m, "auto");
 546                 }
 547                 break;
 548         case AF_INET6:
 549                 switch (nfss->mountd_protocol) {
 550                 case IPPROTO_UDP:
 551                         seq_printf(m, RPCBIND_NETID_UDP6);
 552                         break;
 553                 case IPPROTO_TCP:
 554                         seq_printf(m, RPCBIND_NETID_TCP6);
 555                         break;
 556                 default:
 557                         if (showdefaults)
 558                                 seq_printf(m, "auto");
 559                 }
 560                 break;
 561         default:
 562                 if (showdefaults)
 563                         seq_printf(m, "auto");
 564         }
 565 }
 566
 567 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 568                                     int showdefaults)
 569 {
 570         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 571
 572         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 573                 return;
 574
 575         switch (sap->sa_family) {
 576         case AF_INET: {
 577                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 578                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 579                 break;
 580         }
 581         case AF_INET6: {
 582                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 583                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 584                 break;
 585         }
 586         default:
 587                 if (showdefaults)
 588                         seq_printf(m, ",mountaddr=unspecified");
 589         }
 590
 591         if (nfss->mountd_version || showdefaults)
 592                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 593         if ((nfss->mountd_port &&
 594                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 595                 showdefaults)
 596                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
 597
 598         nfs_show_mountd_netid(m, nfss, showdefaults);
 599 }
 600
 601 #if IS_ENABLED(CONFIG_NFS_V4)
 602 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 603                                     int showdefaults)
 604 {
 605         struct nfs_client *clp = nfss->nfs_client;
 606
 607         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 608 }
 609 #else
 610 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 611                                     int showdefaults)
 612 {
 613 }
 614 #endif
 615
 616 static void nfs_show_nfs_version(struct seq_file *m,
 617                 unsigned int version,
 618                 unsigned int minorversion)
 619 {
 620         seq_printf(m, ",vers=%u", version);
 621         if (version == 4)
 622                 seq_printf(m, ".%u", minorversion);
 623 }
 624
 625 /*
 626  * Describe the mount options in force on this server representation
 627  */
 628 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 629                                    int showdefaults)
 630 {
 631         static const struct proc_nfs_info {
 632                 int flag;
 633                 const char *str;
 634                 const char *nostr;
 635         } nfs_info[] = {
 636                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
 637                 { NFS_MOUNT_POSIX, ",posix", "" },
 638                 { NFS_MOUNT_NOCTO, ",nocto", "" },
 639                 { NFS_MOUNT_NOAC, ",noac", "" },
 640                 { NFS_MOUNT_NONLM, ",nolock", "" },
 641                 { NFS_MOUNT_NOACL, ",noacl", "" },
 642                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 643                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 644                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 645                 { 0, NULL, NULL }
 646         };
 647         const struct proc_nfs_info *nfs_infop;
 648         struct nfs_client *clp = nfss->nfs_client;
 649         u32 version = clp->rpc_ops->version;
 650         int local_flock, local_fcntl;
 651
 652         nfs_show_nfs_version(m, version, clp->cl_minorversion);
 653         seq_printf(m, ",rsize=%u", nfss->rsize);
 654         seq_printf(m, ",wsize=%u", nfss->wsize);
 655         if (nfss->bsize != 0)
 656                 seq_printf(m, ",bsize=%u", nfss->bsize);
 657         seq_printf(m, ",namlen=%u", nfss->namelen);
 658         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 659                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 660         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 661                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 662         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 663                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 664         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 665                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 666         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 667                 if (nfss->flags & nfs_infop->flag)
 668                         seq_puts(m, nfs_infop->str);
 669                 else
 670                         seq_puts(m, nfs_infop->nostr);
 671         }
 672         rcu_read_lock();
 673         seq_printf(m, ",proto=%s",
 674                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 675         rcu_read_unlock();
 676         if (version == 4) {
 677                 if (nfss->port != NFS_PORT)
 678                         seq_printf(m, ",port=%u", nfss->port);
 679         } else
 680                 if (nfss->port)
 681                         seq_printf(m, ",port=%u", nfss->port);
 682
 683         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 684         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 685         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 686
 687         if (version != 4)
 688                 nfs_show_mountd_options(m, nfss, showdefaults);
 689         else
 690                 nfs_show_nfsv4_options(m, nfss, showdefaults);
 691
 692         if (nfss->options & NFS_OPTION_FSCACHE)
 693                 seq_printf(m, ",fsc");
 694
 695         if (nfss->options & NFS_OPTION_MIGRATION)
 696                 seq_printf(m, ",migration");
 697
 698         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 699                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 700                         seq_printf(m, ",lookupcache=none");
 701                 else
 702                         seq_printf(m, ",lookupcache=pos");
 703         }
 704
 705         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 706         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 707
 708         if (!local_flock && !local_fcntl)
 709                 seq_printf(m, ",local_lock=none");
 710         else if (local_flock && local_fcntl)
 711                 seq_printf(m, ",local_lock=all");
 712         else if (local_flock)
 713                 seq_printf(m, ",local_lock=flock");
 714         else
 715                 seq_printf(m, ",local_lock=posix");
 716 }
 717
 718 /*
 719  * Describe the mount options on this VFS mountpoint
 720  */
 721 int nfs_show_options(struct seq_file *m, struct dentry *root)
 722 {
 723         struct nfs_server *nfss = NFS_SB(root->d_sb);
 724
 725         nfs_show_mount_options(m, nfss, 0);
 726
 727         rcu_read_lock();
 728         seq_printf(m, ",addr=%s",
 729                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 730                                                         RPC_DISPLAY_ADDR));
 731         rcu_read_unlock();
 732
 733         return 0;
 734 }
 735 EXPORT_SYMBOL_GPL(nfs_show_options);
 736
 737 #if IS_ENABLED(CONFIG_NFS_V4)
 738 #ifdef CONFIG_NFS_V4_1
 739 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 740 {
 741         if (nfs4_has_session(server->nfs_client))
 742                 seq_printf(m, ",sessions");
 743 }
 744 #else
 745 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 746 #endif
 747 #endif
 748
 749 #ifdef CONFIG_NFS_V4_1
 750 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 751 {
 752         seq_printf(m, ",pnfs=");
 753         if (server->pnfs_curr_ld)
 754                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
 755         else
 756                 seq_printf(m, "not configured");
 757 }
 758
 759 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 760 {
 761         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 762                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 763                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 764                            "date='%llu,%u'",
 765                            impl_id->name, impl_id->domain,
 766                            impl_id->date.seconds, impl_id->date.nseconds);
 767         }
 768 }
 769 #else
 770 #if IS_ENABLED(CONFIG_NFS_V4)
 771 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 772 {
 773 }
 774 #endif
 775 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 776 {
 777 }
 778 #endif
 779
 780 int nfs_show_devname(struct seq_file *m, struct dentry *root)
 781 {
 782         char *page = (char *) __get_free_page(GFP_KERNEL);
 783         char *devname, *dummy;
 784         int err = 0;
 785         if (!page)
 786                 return -ENOMEM;
 787         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 788         if (IS_ERR(devname))
 789                 err = PTR_ERR(devname);
 790         else
 791                 seq_escape(m, devname, " \t\n\\");
 792         free_page((unsigned long)page);
 793         return err;
 794 }
 795 EXPORT_SYMBOL_GPL(nfs_show_devname);
 796
 797 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 798 {
 799         seq_puts(m, "/");
 800         return 0;
 801 }
 802 EXPORT_SYMBOL_GPL(nfs_show_path);
 803
 804 /*
 805  * Present statistical information for this VFS mountpoint
 806  */
 807 int nfs_show_stats(struct seq_file *m, struct dentry *root)
 808 {
 809         int i, cpu;
 810         struct nfs_server *nfss = NFS_SB(root->d_sb);
 811         struct rpc_auth *auth = nfss->client->cl_auth;
 812         struct nfs_iostats totals = { };
 813
 814         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 815
 816         /*
 817          * Display all mount option settings
 818          */
 819         seq_printf(m, "\n\topts:\t");
 820         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 821         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 822         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 823         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 824         nfs_show_mount_options(m, nfss, 1);
 825
 826         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 827
 828         show_implementation_id(m, nfss);
 829
 830         seq_printf(m, "\n\tcaps:\t");
 831         seq_printf(m, "caps=0x%x", nfss->caps);
 832         seq_printf(m, ",wtmult=%u", nfss->wtmult);
 833         seq_printf(m, ",dtsize=%u", nfss->dtsize);
 834         seq_printf(m, ",bsize=%u", nfss->bsize);
 835         seq_printf(m, ",namlen=%u", nfss->namelen);
 836
 837 #if IS_ENABLED(CONFIG_NFS_V4)
 838         if (nfss->nfs_client->rpc_ops->version == 4) {
 839                 seq_printf(m, "\n\tnfsv4:\t");
 840                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 841                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 842                 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
 843                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 844                 show_sessions(m, nfss);
 845                 show_pnfs(m, nfss);
 846         }
 847 #endif
 848
 849         /*
 850          * Display security flavor in effect for this mount
 851          */
 852         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 853         if (auth->au_flavor)
 854                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 855
 856         /*
 857          * Display superblock I/O counters
 858          */
 859         for_each_possible_cpu(cpu) {
 860                 struct nfs_iostats *stats;
 861
 862                 preempt_disable();
 863                 stats = per_cpu_ptr(nfss->io_stats, cpu);
 864
 865                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 866                         totals.events[i] += stats->events[i];
 867                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 868                         totals.bytes[i] += stats->bytes[i];
 869 #ifdef CONFIG_NFS_FSCACHE
 870                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 871                         totals.fscache[i] += stats->fscache[i];
 872 #endif
 873
 874                 preempt_enable();
 875         }
 876
 877         seq_printf(m, "\n\tevents:\t");
 878         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 879                 seq_printf(m, "%lu ", totals.events[i]);
 880         seq_printf(m, "\n\tbytes:\t");
 881         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 882                 seq_printf(m, "%Lu ", totals.bytes[i]);
 883 #ifdef CONFIG_NFS_FSCACHE
 884         if (nfss->options & NFS_OPTION_FSCACHE) {
 885                 seq_printf(m, "\n\tfsc:\t");
 886                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 887                         seq_printf(m, "%Lu ", totals.bytes[i]);
 888         }
 889 #endif
 890         seq_printf(m, "\n");
 891
 892         rpc_print_iostats(m, nfss->client);
 893
 894         return 0;
 895 }
 896 EXPORT_SYMBOL_GPL(nfs_show_stats);
 897
 898 /*
 899  * Begin unmount by attempting to remove all automounted mountpoints we added
 900  * in response to xdev traversals and referrals
 901  */
 902 void nfs_umount_begin(struct super_block *sb)
 903 {
 904         struct nfs_server *server;
 905         struct rpc_clnt *rpc;
 906
 907         server = NFS_SB(sb);
 908         /* -EIO all pending I/O */
 909         rpc = server->client_acl;
 910         if (!IS_ERR(rpc))
 911                 rpc_killall_tasks(rpc);
 912         rpc = server->client;
 913         if (!IS_ERR(rpc))
 914                 rpc_killall_tasks(rpc);
 915 }
 916 EXPORT_SYMBOL_GPL(nfs_umount_begin);
 917
 918 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 919 {
 920         struct nfs_parsed_mount_data *data;
 921
 922         data = kzalloc(sizeof(*data), GFP_KERNEL);
 923         if (data) {
 924                 data->acregmin          = NFS_DEF_ACREGMIN;
 925                 data->acregmax          = NFS_DEF_ACREGMAX;
 926                 data->acdirmin          = NFS_DEF_ACDIRMIN;
 927                 data->acdirmax          = NFS_DEF_ACDIRMAX;
 928                 data->mount_server.port = NFS_UNSPEC_PORT;
 929                 data->nfs_server.port   = NFS_UNSPEC_PORT;
 930                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 931                 data->selected_flavor   = RPC_AUTH_MAXFLAVOR;
 932                 data->minorversion      = 0;
 933                 data->need_mount        = true;
 934                 data->net               = current->nsproxy->net_ns;
 935                 security_init_mnt_opts(&data->lsm_opts);
 936         }
 937         return data;
 938 }
 939
 940 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 941 {
 942         if (data) {
 943                 kfree(data->client_address);
 944                 kfree(data->mount_server.hostname);
 945                 kfree(data->nfs_server.export_path);
 946                 kfree(data->nfs_server.hostname);
 947                 kfree(data->fscache_uniq);
 948                 security_free_mnt_opts(&data->lsm_opts);
 949                 kfree(data);
 950         }
 951 }
 952
 953 /*
 954  * Sanity-check a server address provided by the mount command.
 955  *
 956  * Address family must be initialized, and address must not be
 957  * the ANY address for that family.
 958  */
 959 static int nfs_verify_server_address(struct sockaddr *addr)
 960 {
 961         switch (addr->sa_family) {
 962         case AF_INET: {
 963                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 964                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 965         }
 966         case AF_INET6: {
 967                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 968                 return !ipv6_addr_any(sa);
 969         }
 970         }
 971
 972         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 973         return 0;
 974 }
 975
 976 /*
 977  * Select between a default port value and a user-specified port value.
 978  * If a zero value is set, then autobind will be used.
 979  */
 980 static void nfs_set_port(struct sockaddr *sap, int *port,
 981                                  const unsigned short default_port)
 982 {
 983         if (*port == NFS_UNSPEC_PORT)
 984                 *port = default_port;
 985
 986         rpc_set_port(sap, *port);
 987 }
 988
 989 /*
 990  * Sanity check the NFS transport protocol.
 991  *
 992  */
 993 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 994 {
 995         switch (mnt->nfs_server.protocol) {
 996         case XPRT_TRANSPORT_UDP:
 997         case XPRT_TRANSPORT_TCP:
 998         case XPRT_TRANSPORT_RDMA:
 999                 break;
1000         default:
1001                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1002         }
1003 }
1004
1005 /*
1006  * For text based NFSv2/v3 mounts, the mount protocol transport default
1007  * settings should depend upon the specified NFS transport.
1008  */
1009 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1010 {
1011         nfs_validate_transport_protocol(mnt);
1012
1013         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1014             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1015                         return;
1016         switch (mnt->nfs_server.protocol) {
1017         case XPRT_TRANSPORT_UDP:
1018                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1019                 break;
1020         case XPRT_TRANSPORT_TCP:
1021         case XPRT_TRANSPORT_RDMA:
1022                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1023         }
1024 }
1025
1026 /*
1027  * Add 'flavor' to 'auth_info' if not already present.
1028  * Returns true if 'flavor' ends up in the list, false otherwise
1029  */
1030 static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
1031                               rpc_authflavor_t flavor)
1032 {
1033         unsigned int i;
1034         unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
1035
1036         /* make sure this flavor isn't already in the list */
1037         for (i = 0; i < auth_info->flavor_len; i++) {
1038                 if (flavor == auth_info->flavors[i])
1039                         return true;
1040         }
1041
1042         if (auth_info->flavor_len + 1 >= max_flavor_len) {
1043                 dfprintk(MOUNT, "NFS: too many sec= flavors\n");
1044                 return false;
1045         }
1046
1047         auth_info->flavors[auth_info->flavor_len++] = flavor;
1048         return true;
1049 }
1050
1051 /*
1052  * Return true if 'match' is in auth_info or auth_info is empty.
1053  * Return false otherwise.
1054  */
1055 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
1056                          rpc_authflavor_t match)
1057 {
1058         int i;
1059
1060         if (!auth_info->flavor_len)
1061                 return true;
1062
1063         for (i = 0; i < auth_info->flavor_len; i++) {
1064                 if (auth_info->flavors[i] == match)
1065                         return true;
1066         }
1067         return false;
1068 }
1069 EXPORT_SYMBOL_GPL(nfs_auth_info_match);
1070
1071 /*
1072  * Parse the value of the 'sec=' option.
1073  */
1074 static int nfs_parse_security_flavors(char *value,
1075                                       struct nfs_parsed_mount_data *mnt)
1076 {
1077         substring_t args[MAX_OPT_ARGS];
1078         rpc_authflavor_t pseudoflavor;
1079         char *p;
1080
1081         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1082
1083         while ((p = strsep(&value, ":")) != NULL) {
1084                 switch (match_token(p, nfs_secflavor_tokens, args)) {
1085                 case Opt_sec_none:
1086                         pseudoflavor = RPC_AUTH_NULL;
1087                         break;
1088                 case Opt_sec_sys:
1089                         pseudoflavor = RPC_AUTH_UNIX;
1090                         break;
1091                 case Opt_sec_krb5:
1092                         pseudoflavor = RPC_AUTH_GSS_KRB5;
1093                         break;
1094                 case Opt_sec_krb5i:
1095                         pseudoflavor = RPC_AUTH_GSS_KRB5I;
1096                         break;
1097                 case Opt_sec_krb5p:
1098                         pseudoflavor = RPC_AUTH_GSS_KRB5P;
1099                         break;
1100                 case Opt_sec_lkey:
1101                         pseudoflavor = RPC_AUTH_GSS_LKEY;
1102                         break;
1103                 case Opt_sec_lkeyi:
1104                         pseudoflavor = RPC_AUTH_GSS_LKEYI;
1105                         break;
1106                 case Opt_sec_lkeyp:
1107                         pseudoflavor = RPC_AUTH_GSS_LKEYP;
1108                         break;
1109                 case Opt_sec_spkm:
1110                         pseudoflavor = RPC_AUTH_GSS_SPKM;
1111                         break;
1112                 case Opt_sec_spkmi:
1113                         pseudoflavor = RPC_AUTH_GSS_SPKMI;
1114                         break;
1115                 case Opt_sec_spkmp:
1116                         pseudoflavor = RPC_AUTH_GSS_SPKMP;
1117                         break;
1118                 default:
1119                         dfprintk(MOUNT,
1120                                  "NFS: sec= option '%s' not recognized\n", p);
1121                         return 0;
1122                 }
1123
1124                 if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
1125                         return 0;
1126         }
1127
1128         return 1;
1129 }
1130
1131 static int nfs_parse_version_string(char *string,
1132                 struct nfs_parsed_mount_data *mnt,
1133                 substring_t *args)
1134 {
1135         mnt->flags &= ~NFS_MOUNT_VER3;
1136         switch (match_token(string, nfs_vers_tokens, args)) {
1137         case Opt_vers_2:
1138                 mnt->version = 2;
1139                 break;
1140         case Opt_vers_3:
1141                 mnt->flags |= NFS_MOUNT_VER3;
1142                 mnt->version = 3;
1143                 break;
1144         case Opt_vers_4:
1145                 /* Backward compatibility option. In future,
1146                  * the mount program should always supply
1147                  * a NFSv4 minor version number.
1148                  */
1149                 mnt->version = 4;
1150                 break;
1151         case Opt_vers_4_0:
1152                 mnt->version = 4;
1153                 mnt->minorversion = 0;
1154                 break;
1155         case Opt_vers_4_1:
1156                 mnt->version = 4;
1157                 mnt->minorversion = 1;
1158                 break;
1159         case Opt_vers_4_2:
1160                 mnt->version = 4;
1161                 mnt->minorversion = 2;
1162                 break;
1163         default:
1164                 return 0;
1165         }
1166         return 1;
1167 }
1168
1169 static int nfs_get_option_str(substring_t args[], char **option)
1170 {
1171         kfree(*option);
1172         *option = match_strdup(args);
1173         return !*option;
1174 }
1175
1176 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1177 {
1178         int rc;
1179         char *string;
1180
1181         string = match_strdup(args);
1182         if (string == NULL)
1183                 return -ENOMEM;
1184         rc = kstrtoul(string, 10, option);
1185         kfree(string);
1186
1187         return rc;
1188 }
1189
1190 /*
1191  * Error-check and convert a string of mount options from user space into
1192  * a data structure.  The whole mount string is processed; bad options are
1193  * skipped as they are encountered.  If there were no errors, return 1;
1194  * otherwise return 0 (zero).
1195  */
1196 static int nfs_parse_mount_options(char *raw,
1197                                    struct nfs_parsed_mount_data *mnt)
1198 {
1199         char *p, *string, *secdata;
1200         int rc, sloppy = 0, invalid_option = 0;
1201         unsigned short protofamily = AF_UNSPEC;
1202         unsigned short mountfamily = AF_UNSPEC;
1203
1204         if (!raw) {
1205                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1206                 return 1;
1207         }
1208         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1209
1210         secdata = alloc_secdata();
1211         if (!secdata)
1212                 goto out_nomem;
1213
1214         rc = security_sb_copy_data(raw, secdata);
1215         if (rc)
1216                 goto out_security_failure;
1217
1218         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1219         if (rc)
1220                 goto out_security_failure;
1221
1222         free_secdata(secdata);
1223
1224         while ((p = strsep(&raw, ",")) != NULL) {
1225                 substring_t args[MAX_OPT_ARGS];
1226                 unsigned long option;
1227                 int token;
1228
1229                 if (!*p)
1230                         continue;
1231
1232                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1233
1234                 token = match_token(p, nfs_mount_option_tokens, args);
1235                 switch (token) {
1236
1237                 /*
1238                  * boolean options:  foo/nofoo
1239                  */
1240                 case Opt_soft:
1241                         mnt->flags |= NFS_MOUNT_SOFT;
1242                         break;
1243                 case Opt_hard:
1244                         mnt->flags &= ~NFS_MOUNT_SOFT;
1245                         break;
1246                 case Opt_posix:
1247                         mnt->flags |= NFS_MOUNT_POSIX;
1248                         break;
1249                 case Opt_noposix:
1250                         mnt->flags &= ~NFS_MOUNT_POSIX;
1251                         break;
1252                 case Opt_cto:
1253                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1254                         break;
1255                 case Opt_nocto:
1256                         mnt->flags |= NFS_MOUNT_NOCTO;
1257                         break;
1258                 case Opt_ac:
1259                         mnt->flags &= ~NFS_MOUNT_NOAC;
1260                         break;
1261                 case Opt_noac:
1262                         mnt->flags |= NFS_MOUNT_NOAC;
1263                         break;
1264                 case Opt_lock:
1265                         mnt->flags &= ~NFS_MOUNT_NONLM;
1266                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1267                                         NFS_MOUNT_LOCAL_FCNTL);
1268                         break;
1269                 case Opt_nolock:
1270                         mnt->flags |= NFS_MOUNT_NONLM;
1271                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1272                                        NFS_MOUNT_LOCAL_FCNTL);
1273                         break;
1274                 case Opt_udp:
1275                         mnt->flags &= ~NFS_MOUNT_TCP;
1276                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1277                         break;
1278                 case Opt_tcp:
1279                         mnt->flags |= NFS_MOUNT_TCP;
1280                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1281                         break;
1282                 case Opt_rdma:
1283                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1284                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1285                         xprt_load_transport(p);
1286                         break;
1287                 case Opt_acl:
1288                         mnt->flags &= ~NFS_MOUNT_NOACL;
1289                         break;
1290                 case Opt_noacl:
1291                         mnt->flags |= NFS_MOUNT_NOACL;
1292                         break;
1293                 case Opt_rdirplus:
1294                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1295                         break;
1296                 case Opt_nordirplus:
1297                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1298                         break;
1299                 case Opt_sharecache:
1300                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1301                         break;
1302                 case Opt_nosharecache:
1303                         mnt->flags |= NFS_MOUNT_UNSHARED;
1304                         break;
1305                 case Opt_resvport:
1306                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1307                         break;
1308                 case Opt_noresvport:
1309                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1310                         break;
1311                 case Opt_fscache:
1312                         mnt->options |= NFS_OPTION_FSCACHE;
1313                         kfree(mnt->fscache_uniq);
1314                         mnt->fscache_uniq = NULL;
1315                         break;
1316                 case Opt_nofscache:
1317                         mnt->options &= ~NFS_OPTION_FSCACHE;
1318                         kfree(mnt->fscache_uniq);
1319                         mnt->fscache_uniq = NULL;
1320                         break;
1321                 case Opt_migration:
1322                         mnt->options |= NFS_OPTION_MIGRATION;
1323                         break;
1324                 case Opt_nomigration:
1325                         mnt->options &= NFS_OPTION_MIGRATION;
1326                         break;
1327
1328                 /*
1329                  * options that take numeric values
1330                  */
1331                 case Opt_port:
1332                         if (nfs_get_option_ul(args, &option) ||
1333                             option > USHRT_MAX)
1334                                 goto out_invalid_value;
1335                         mnt->nfs_server.port = option;
1336                         break;
1337                 case Opt_rsize:
1338                         if (nfs_get_option_ul(args, &option))
1339                                 goto out_invalid_value;
1340                         mnt->rsize = option;
1341                         break;
1342                 case Opt_wsize:
1343                         if (nfs_get_option_ul(args, &option))
1344                                 goto out_invalid_value;
1345                         mnt->wsize = option;
1346                         break;
1347                 case Opt_bsize:
1348                         if (nfs_get_option_ul(args, &option))
1349                                 goto out_invalid_value;
1350                         mnt->bsize = option;
1351                         break;
1352                 case Opt_timeo:
1353                         if (nfs_get_option_ul(args, &option) || option == 0)
1354                                 goto out_invalid_value;
1355                         mnt->timeo = option;
1356                         break;
1357                 case Opt_retrans:
1358                         if (nfs_get_option_ul(args, &option) || option == 0)
1359                                 goto out_invalid_value;
1360                         mnt->retrans = option;
1361                         break;
1362                 case Opt_acregmin:
1363                         if (nfs_get_option_ul(args, &option))
1364                                 goto out_invalid_value;
1365                         mnt->acregmin = option;
1366                         break;
1367                 case Opt_acregmax:
1368                         if (nfs_get_option_ul(args, &option))
1369                                 goto out_invalid_value;
1370                         mnt->acregmax = option;
1371                         break;
1372                 case Opt_acdirmin:
1373                         if (nfs_get_option_ul(args, &option))
1374                                 goto out_invalid_value;
1375                         mnt->acdirmin = option;
1376                         break;
1377                 case Opt_acdirmax:
1378                         if (nfs_get_option_ul(args, &option))
1379                                 goto out_invalid_value;
1380                         mnt->acdirmax = option;
1381                         break;
1382                 case Opt_actimeo:
1383                         if (nfs_get_option_ul(args, &option))
1384                                 goto out_invalid_value;
1385                         mnt->acregmin = mnt->acregmax =
1386                         mnt->acdirmin = mnt->acdirmax = option;
1387                         break;
1388                 case Opt_namelen:
1389                         if (nfs_get_option_ul(args, &option))
1390                                 goto out_invalid_value;
1391                         mnt->namlen = option;
1392                         break;
1393                 case Opt_mountport:
1394                         if (nfs_get_option_ul(args, &option) ||
1395                             option > USHRT_MAX)
1396                                 goto out_invalid_value;
1397                         mnt->mount_server.port = option;
1398                         break;
1399                 case Opt_mountvers:
1400                         if (nfs_get_option_ul(args, &option) ||
1401                             option < NFS_MNT_VERSION ||
1402                             option > NFS_MNT3_VERSION)
1403                                 goto out_invalid_value;
1404                         mnt->mount_server.version = option;
1405                         break;
1406                 case Opt_minorversion:
1407                         if (nfs_get_option_ul(args, &option))
1408                                 goto out_invalid_value;
1409                         if (option > NFS4_MAX_MINOR_VERSION)
1410                                 goto out_invalid_value;
1411                         mnt->minorversion = option;
1412                         break;
1413
1414                 /*
1415                  * options that take text values
1416                  */
1417                 case Opt_nfsvers:
1418                         string = match_strdup(args);
1419                         if (string == NULL)
1420                                 goto out_nomem;
1421                         rc = nfs_parse_version_string(string, mnt, args);
1422                         kfree(string);
1423                         if (!rc)
1424                                 goto out_invalid_value;
1425                         break;
1426                 case Opt_sec:
1427                         string = match_strdup(args);
1428                         if (string == NULL)
1429                                 goto out_nomem;
1430                         rc = nfs_parse_security_flavors(string, mnt);
1431                         kfree(string);
1432                         if (!rc) {
1433                                 dfprintk(MOUNT, "NFS:   unrecognized "
1434                                                 "security flavor\n");
1435                                 return 0;
1436                         }
1437                         break;
1438                 case Opt_proto:
1439                         string = match_strdup(args);
1440                         if (string == NULL)
1441                                 goto out_nomem;
1442                         token = match_token(string,
1443                                             nfs_xprt_protocol_tokens, args);
1444
1445                         protofamily = AF_INET;
1446                         switch (token) {
1447                         case Opt_xprt_udp6:
1448                                 protofamily = AF_INET6;
1449                         case Opt_xprt_udp:
1450                                 mnt->flags &= ~NFS_MOUNT_TCP;
1451                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1452                                 break;
1453                         case Opt_xprt_tcp6:
1454                                 protofamily = AF_INET6;
1455                         case Opt_xprt_tcp:
1456                                 mnt->flags |= NFS_MOUNT_TCP;
1457                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1458                                 break;
1459                         case Opt_xprt_rdma:
1460                                 /* vector side protocols to TCP */
1461                                 mnt->flags |= NFS_MOUNT_TCP;
1462                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1463                                 xprt_load_transport(string);
1464                                 break;
1465                         default:
1466                                 dfprintk(MOUNT, "NFS:   unrecognized "
1467                                                 "transport protocol\n");
1468                                 kfree(string);
1469                                 return 0;
1470                         }
1471                         kfree(string);
1472                         break;
1473                 case Opt_mountproto:
1474                         string = match_strdup(args);
1475                         if (string == NULL)
1476                                 goto out_nomem;
1477                         token = match_token(string,
1478                                             nfs_xprt_protocol_tokens, args);
1479                         kfree(string);
1480
1481                         mountfamily = AF_INET;
1482                         switch (token) {
1483                         case Opt_xprt_udp6:
1484                                 mountfamily = AF_INET6;
1485                         case Opt_xprt_udp:
1486                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1487                                 break;
1488                         case Opt_xprt_tcp6:
1489                                 mountfamily = AF_INET6;
1490                         case Opt_xprt_tcp:
1491                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1492                                 break;
1493                         case Opt_xprt_rdma: /* not used for side protocols */
1494                         default:
1495                                 dfprintk(MOUNT, "NFS:   unrecognized "
1496                                                 "transport protocol\n");
1497                                 return 0;
1498                         }
1499                         break;
1500                 case Opt_addr:
1501                         string = match_strdup(args);
1502                         if (string == NULL)
1503                                 goto out_nomem;
1504                         mnt->nfs_server.addrlen =
1505                                 rpc_pton(mnt->net, string, strlen(string),
1506                                         (struct sockaddr *)
1507                                         &mnt->nfs_server.address,
1508                                         sizeof(mnt->nfs_server.address));
1509                         kfree(string);
1510                         if (mnt->nfs_server.addrlen == 0)
1511                                 goto out_invalid_address;
1512                         break;
1513                 case Opt_clientaddr:
1514                         if (nfs_get_option_str(args, &mnt->client_address))
1515                                 goto out_nomem;
1516                         break;
1517                 case Opt_mounthost:
1518                         if (nfs_get_option_str(args,
1519                                                &mnt->mount_server.hostname))
1520                                 goto out_nomem;
1521                         break;
1522                 case Opt_mountaddr:
1523                         string = match_strdup(args);
1524                         if (string == NULL)
1525                                 goto out_nomem;
1526                         mnt->mount_server.addrlen =
1527                                 rpc_pton(mnt->net, string, strlen(string),
1528                                         (struct sockaddr *)
1529                                         &mnt->mount_server.address,
1530                                         sizeof(mnt->mount_server.address));
1531                         kfree(string);
1532                         if (mnt->mount_server.addrlen == 0)
1533                                 goto out_invalid_address;
1534                         break;
1535                 case Opt_lookupcache:
1536                         string = match_strdup(args);
1537                         if (string == NULL)
1538                                 goto out_nomem;
1539                         token = match_token(string,
1540                                         nfs_lookupcache_tokens, args);
1541                         kfree(string);
1542                         switch (token) {
1543                                 case Opt_lookupcache_all:
1544                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1545                                         break;
1546                                 case Opt_lookupcache_positive:
1547                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1548                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1549                                         break;
1550                                 case Opt_lookupcache_none:
1551                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1552                                         break;
1553                                 default:
1554                                         dfprintk(MOUNT, "NFS:   invalid "
1555                                                         "lookupcache argument\n");
1556                                         return 0;
1557                         };
1558                         break;
1559                 case Opt_fscache_uniq:
1560                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1561                                 goto out_nomem;
1562                         mnt->options |= NFS_OPTION_FSCACHE;
1563                         break;
1564                 case Opt_local_lock:
1565                         string = match_strdup(args);
1566                         if (string == NULL)
1567                                 goto out_nomem;
1568                         token = match_token(string, nfs_local_lock_tokens,
1569                                         args);
1570                         kfree(string);
1571                         switch (token) {
1572                         case Opt_local_lock_all:
1573                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1574                                                NFS_MOUNT_LOCAL_FCNTL);
1575                                 break;
1576                         case Opt_local_lock_flock:
1577                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1578                                 break;
1579                         case Opt_local_lock_posix:
1580                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1581                                 break;
1582                         case Opt_local_lock_none:
1583                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1584                                                 NFS_MOUNT_LOCAL_FCNTL);
1585                                 break;
1586                         default:
1587                                 dfprintk(MOUNT, "NFS:   invalid "
1588                                                 "local_lock argument\n");
1589                                 return 0;
1590                         };
1591                         break;
1592
1593                 /*
1594                  * Special options
1595                  */
1596                 case Opt_sloppy:
1597                         sloppy = 1;
1598                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1599                         break;
1600                 case Opt_userspace:
1601                 case Opt_deprecated:
1602                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1603                                         "'%s'\n", p);
1604                         break;
1605
1606                 default:
1607                         invalid_option = 1;
1608                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1609                                         "'%s'\n", p);
1610                 }
1611         }
1612
1613         if (!sloppy && invalid_option)
1614                 return 0;
1615
1616         if (mnt->minorversion && mnt->version != 4)
1617                 goto out_minorversion_mismatch;
1618
1619         if (mnt->options & NFS_OPTION_MIGRATION &&
1620             (mnt->version != 4 || mnt->minorversion != 0))
1621                 goto out_migration_misuse;
1622
1623         /*
1624          * verify that any proto=/mountproto= options match the address
1625          * families in the addr=/mountaddr= options.
1626          */
1627         if (protofamily != AF_UNSPEC &&
1628             protofamily != mnt->nfs_server.address.ss_family)
1629                 goto out_proto_mismatch;
1630
1631         if (mountfamily != AF_UNSPEC) {
1632                 if (mnt->mount_server.addrlen) {
1633                         if (mountfamily != mnt->mount_server.address.ss_family)
1634                                 goto out_mountproto_mismatch;
1635                 } else {
1636                         if (mountfamily != mnt->nfs_server.address.ss_family)
1637                                 goto out_mountproto_mismatch;
1638                 }
1639         }
1640
1641         return 1;
1642
1643 out_mountproto_mismatch:
1644         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1645                          "option\n");
1646         return 0;
1647 out_proto_mismatch:
1648         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1649         return 0;
1650 out_invalid_address:
1651         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1652         return 0;
1653 out_invalid_value:
1654         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1655         return 0;
1656 out_minorversion_mismatch:
1657         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1658                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1659         return 0;
1660 out_migration_misuse:
1661         printk(KERN_INFO
1662                 "NFS: 'migration' not supported for this NFS version\n");
1663         return 0;
1664 out_nomem:
1665         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1666         return 0;
1667 out_security_failure:
1668         free_secdata(secdata);
1669         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1670         return 0;
1671 }
1672
1673 /*
1674  * Ensure that a specified authtype in args->auth_info is supported by
1675  * the server. Returns 0 and sets args->selected_flavor if it's ok, and
1676  * -EACCES if not.
1677  */
1678 static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
1679                         rpc_authflavor_t *server_authlist, unsigned int count)
1680 {
1681         rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
1682         unsigned int i;
1683
1684         /*
1685          * If the sec= mount option is used, the specified flavor or AUTH_NULL
1686          * must be in the list returned by the server.
1687          *
1688          * AUTH_NULL has a special meaning when it's in the server list - it
1689          * means that the server will ignore the rpc creds, so any flavor
1690          * can be used.
1691          */
1692         for (i = 0; i < count; i++) {
1693                 flavor = server_authlist[i];
1694
1695                 if (nfs_auth_info_match(&args->auth_info, flavor) ||
1696                     flavor == RPC_AUTH_NULL)
1697                         goto out;
1698         }
1699
1700         dfprintk(MOUNT,
1701                  "NFS: specified auth flavors not supported by server\n");
1702         return -EACCES;
1703
1704 out:
1705         args->selected_flavor = flavor;
1706         dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
1707         return 0;
1708 }
1709
1710 /*
1711  * Use the remote server's MOUNT service to request the NFS file handle
1712  * corresponding to the provided path.
1713  */
1714 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1715                              struct nfs_fh *root_fh,
1716                              rpc_authflavor_t *server_authlist,
1717                              unsigned int *server_authlist_len)
1718 {
1719         struct nfs_mount_request request = {
1720                 .sap            = (struct sockaddr *)
1721                                                 &args->mount_server.address,
1722                 .dirpath        = args->nfs_server.export_path,
1723                 .protocol       = args->mount_server.protocol,
1724                 .fh             = root_fh,
1725                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1726                 .auth_flav_len  = server_authlist_len,
1727                 .auth_flavs     = server_authlist,
1728                 .net            = args->net,
1729         };
1730         int status;
1731
1732         if (args->mount_server.version == 0) {
1733                 switch (args->version) {
1734                         default:
1735                                 args->mount_server.version = NFS_MNT3_VERSION;
1736                                 break;
1737                         case 2:
1738                                 args->mount_server.version = NFS_MNT_VERSION;
1739                 }
1740         }
1741         request.version = args->mount_server.version;
1742
1743         if (args->mount_server.hostname)
1744                 request.hostname = args->mount_server.hostname;
1745         else
1746                 request.hostname = args->nfs_server.hostname;
1747
1748         /*
1749          * Construct the mount server's address.
1750          */
1751         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1752                 memcpy(request.sap, &args->nfs_server.address,
1753                        args->nfs_server.addrlen);
1754                 args->mount_server.addrlen = args->nfs_server.addrlen;
1755         }
1756         request.salen = args->mount_server.addrlen;
1757         nfs_set_port(request.sap, &args->mount_server.port, 0);
1758
1759         /*
1760          * Now ask the mount server to map our export path
1761          * to a file handle.
1762          */
1763         status = nfs_mount(&request);
1764         if (status != 0) {
1765                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1766                                 request.hostname, status);
1767                 return status;
1768         }
1769
1770         return 0;
1771 }
1772
1773 static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1774                                         struct nfs_subversion *nfs_mod)
1775 {
1776         int status;
1777         unsigned int i;
1778         bool tried_auth_unix = false;
1779         bool auth_null_in_list = false;
1780         struct nfs_server *server = ERR_PTR(-EACCES);
1781         struct nfs_parsed_mount_data *args = mount_info->parsed;
1782         rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1783         unsigned int authlist_len = ARRAY_SIZE(authlist);
1784
1785         status = nfs_request_mount(args, mount_info->mntfh, authlist,
1786                                         &authlist_len);
1787         if (status)
1788                 return ERR_PTR(status);
1789
1790         /*
1791          * Was a sec= authflavor specified in the options? First, verify
1792          * whether the server supports it, and then just try to use it if so.
1793          */
1794         if (args->auth_info.flavor_len > 0) {
1795                 status = nfs_verify_authflavors(args, authlist, authlist_len);
1796                 dfprintk(MOUNT, "NFS: using auth flavor %u\n",
1797                          args->selected_flavor);
1798                 if (status)
1799                         return ERR_PTR(status);
1800                 return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1801         }
1802
1803         /*
1804          * No sec= option was provided. RFC 2623, section 2.7 suggests we
1805          * SHOULD prefer the flavor listed first. However, some servers list
1806          * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1807          */
1808         for (i = 0; i < authlist_len; ++i) {
1809                 rpc_authflavor_t flavor;
1810                 struct rpcsec_gss_info info;
1811
1812                 flavor = authlist[i];
1813                 switch (flavor) {
1814                 case RPC_AUTH_UNIX:
1815                         tried_auth_unix = true;
1816                         break;
1817                 case RPC_AUTH_NULL:
1818                         auth_null_in_list = true;
1819                         continue;
1820                 default:
1821                         if (rpcauth_get_gssinfo(flavor, &info) != 0)
1822                                 continue;
1823                         /* Fallthrough */
1824                 }
1825                 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1826                 args->selected_flavor = flavor;
1827                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1828                 if (!IS_ERR(server))
1829                         return server;
1830         }
1831
1832         /*
1833          * Nothing we tried so far worked. At this point, give up if we've
1834          * already tried AUTH_UNIX or if the server's list doesn't contain
1835          * AUTH_NULL
1836          */
1837         if (tried_auth_unix || !auth_null_in_list)
1838                 return server;
1839
1840         /* Last chance! Try AUTH_UNIX */
1841         dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1842         args->selected_flavor = RPC_AUTH_UNIX;
1843         return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1844 }
1845
1846 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1847                              struct nfs_mount_info *mount_info,
1848                              struct nfs_subversion *nfs_mod)
1849 {
1850         struct nfs_server *server;
1851
1852         if (mount_info->parsed->need_mount)
1853                 server = nfs_try_mount_request(mount_info, nfs_mod);
1854         else
1855                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1856
1857         if (IS_ERR(server))
1858                 return ERR_CAST(server);
1859
1860         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1861 }
1862 EXPORT_SYMBOL_GPL(nfs_try_mount);
1863
1864 /*
1865  * Split "dev_name" into "hostname:export_path".
1866  *
1867  * The leftmost colon demarks the split between the server's hostname
1868  * and the export path.  If the hostname starts with a left square
1869  * bracket, then it may contain colons.
1870  *
1871  * Note: caller frees hostname and export path, even on error.
1872  */
1873 static int nfs_parse_devname(const char *dev_name,
1874                              char **hostname, size_t maxnamlen,
1875                              char **export_path, size_t maxpathlen)
1876 {
1877         size_t len;
1878         char *end;
1879
1880         /* Is the host name protected with square brakcets? */
1881         if (*dev_name == '[') {
1882                 end = strchr(++dev_name, ']');
1883                 if (end == NULL || end[1] != ':')
1884                         goto out_bad_devname;
1885
1886                 len = end - dev_name;
1887                 end++;
1888         } else {
1889                 char *comma;
1890
1891                 end = strchr(dev_name, ':');
1892                 if (end == NULL)
1893                         goto out_bad_devname;
1894                 len = end - dev_name;
1895
1896                 /* kill possible hostname list: not supported */
1897                 comma = strchr(dev_name, ',');
1898                 if (comma != NULL && comma < end)
1899                         *comma = 0;
1900         }
1901
1902         if (len > maxnamlen)
1903                 goto out_hostname;
1904
1905         /* N.B. caller will free nfs_server.hostname in all cases */
1906         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1907         if (*hostname == NULL)
1908                 goto out_nomem;
1909         len = strlen(++end);
1910         if (len > maxpathlen)
1911                 goto out_path;
1912         *export_path = kstrndup(end, len, GFP_KERNEL);
1913         if (!*export_path)
1914                 goto out_nomem;
1915
1916         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1917         return 0;
1918
1919 out_bad_devname:
1920         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1921         return -EINVAL;
1922
1923 out_nomem:
1924         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1925         return -ENOMEM;
1926
1927 out_hostname:
1928         dfprintk(MOUNT, "NFS: server hostname too long\n");
1929         return -ENAMETOOLONG;
1930
1931 out_path:
1932         dfprintk(MOUNT, "NFS: export pathname too long\n");
1933         return -ENAMETOOLONG;
1934 }
1935
1936 /*
1937  * Validate the NFS2/NFS3 mount data
1938  * - fills in the mount root filehandle
1939  *
1940  * For option strings, user space handles the following behaviors:
1941  *
1942  * + DNS: mapping server host name to IP address ("addr=" option)
1943  *
1944  * + failure mode: how to behave if a mount request can't be handled
1945  *   immediately ("fg/bg" option)
1946  *
1947  * + retry: how often to retry a mount request ("retry=" option)
1948  *
1949  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1950  *   mountproto=tcp after mountproto=udp, and so on
1951  */
1952 static int nfs23_validate_mount_data(void *options,
1953                                      struct nfs_parsed_mount_data *args,
1954                                      struct nfs_fh *mntfh,
1955                                      const char *dev_name)
1956 {
1957         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1958         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1959         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1960
1961         if (data == NULL)
1962                 goto out_no_data;
1963
1964         args->version = NFS_DEFAULT_VERSION;
1965         switch (data->version) {
1966         case 1:
1967                 data->namlen = 0;
1968         case 2:
1969                 data->bsize = 0;
1970         case 3:
1971                 if (data->flags & NFS_MOUNT_VER3)
1972                         goto out_no_v3;
1973                 data->root.size = NFS2_FHSIZE;
1974                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1975                 /* Turn off security negotiation */
1976                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
1977         case 4:
1978                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1979                         goto out_no_sec;
1980         case 5:
1981                 memset(data->context, 0, sizeof(data->context));
1982         case 6:
1983                 if (data->flags & NFS_MOUNT_VER3) {
1984                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1985                                 goto out_invalid_fh;
1986                         mntfh->size = data->root.size;
1987                         args->version = 3;
1988                 } else {
1989                         mntfh->size = NFS2_FHSIZE;
1990                         args->version = 2;
1991                 }
1992
1993
1994                 memcpy(mntfh->data, data->root.data, mntfh->size);
1995                 if (mntfh->size < sizeof(mntfh->data))
1996                         memset(mntfh->data + mntfh->size, 0,
1997                                sizeof(mntfh->data) - mntfh->size);
1998
1999                 /*
2000                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
2001                  * can deal with.
2002                  */
2003                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
2004                 args->flags             |= extra_flags;
2005                 args->rsize             = data->rsize;
2006                 args->wsize             = data->wsize;
2007                 args->timeo             = data->timeo;
2008                 args->retrans           = data->retrans;
2009                 args->acregmin          = data->acregmin;
2010                 args->acregmax          = data->acregmax;
2011                 args->acdirmin          = data->acdirmin;
2012                 args->acdirmax          = data->acdirmax;
2013                 args->need_mount        = false;
2014
2015                 memcpy(sap, &data->addr, sizeof(data->addr));
2016                 args->nfs_server.addrlen = sizeof(data->addr);
2017                 args->nfs_server.port = ntohs(data->addr.sin_port);
2018                 if (!nfs_verify_server_address(sap))
2019                         goto out_no_address;
2020
2021                 if (!(data->flags & NFS_MOUNT_TCP))
2022                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
2023                 /* N.B. caller will free nfs_server.hostname in all cases */
2024                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
2025                 args->namlen            = data->namlen;
2026                 args->bsize             = data->bsize;
2027
2028                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
2029                         args->selected_flavor = data->pseudoflavor;
2030                 else
2031                         args->selected_flavor = RPC_AUTH_UNIX;
2032                 if (!args->nfs_server.hostname)
2033                         goto out_nomem;
2034
2035                 if (!(data->flags & NFS_MOUNT_NONLM))
2036                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
2037                                          NFS_MOUNT_LOCAL_FCNTL);
2038                 else
2039                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
2040                                         NFS_MOUNT_LOCAL_FCNTL);
2041                 /*
2042                  * The legacy version 6 binary mount data from userspace has a
2043                  * field used only to transport selinux information into the
2044                  * the kernel.  To continue to support that functionality we
2045                  * have a touch of selinux knowledge here in the NFS code. The
2046                  * userspace code converted context=blah to just blah so we are
2047                  * converting back to the full string selinux understands.
2048                  */
2049                 if (data->context[0]){
2050 #ifdef CONFIG_SECURITY_SELINUX
2051                         int rc;
2052                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
2053                         if (!opts_str)
2054                                 return -ENOMEM;
2055                         strcpy(opts_str, "context=");
2056                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
2057                         strcat(opts_str, &data->context[0]);
2058                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
2059                         kfree(opts_str);
2060                         if (rc)
2061                                 return rc;
2062 #else
2063                         return -EINVAL;
2064 #endif
2065                 }
2066
2067                 break;
2068         default:
2069                 return NFS_TEXT_DATA;
2070         }
2071
2072         return 0;
2073
2074 out_no_data:
2075         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2076         return -EINVAL;
2077
2078 out_no_v3:
2079         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2080                  data->version);
2081         return -EINVAL;
2082
2083 out_no_sec:
2084         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2085         return -EINVAL;
2086
2087 out_nomem:
2088         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2089         return -ENOMEM;
2090
2091 out_no_address:
2092         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2093         return -EINVAL;
2094
2095 out_invalid_fh:
2096         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2097         return -EINVAL;
2098 }
2099
2100 #if IS_ENABLED(CONFIG_NFS_V4)
2101 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2102                                    void *options,
2103                                    struct nfs_parsed_mount_data *args,
2104                                    struct nfs_fh *mntfh,
2105                                    const char *dev_name)
2106 {
2107         if (fs_type == &nfs_fs_type)
2108                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2109         return nfs4_validate_mount_data(options, args, dev_name);
2110 }
2111 #else
2112 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2113                                    void *options,
2114                                    struct nfs_parsed_mount_data *args,
2115                                    struct nfs_fh *mntfh,
2116                                    const char *dev_name)
2117 {
2118         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2119 }
2120 #endif
2121
2122 static int nfs_validate_text_mount_data(void *options,
2123                                         struct nfs_parsed_mount_data *args,
2124                                         const char *dev_name)
2125 {
2126         int port = 0;
2127         int max_namelen = PAGE_SIZE;
2128         int max_pathlen = NFS_MAXPATHLEN;
2129         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2130
2131         if (nfs_parse_mount_options((char *)options, args) == 0)
2132                 return -EINVAL;
2133
2134         if (!nfs_verify_server_address(sap))
2135                 goto out_no_address;
2136
2137         if (args->version == 4) {
2138 #if IS_ENABLED(CONFIG_NFS_V4)
2139                 port = NFS_PORT;
2140                 max_namelen = NFS4_MAXNAMLEN;
2141                 max_pathlen = NFS4_MAXPATHLEN;
2142                 nfs_validate_transport_protocol(args);
2143                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2144                         goto out_invalid_transport_udp;
2145                 nfs4_validate_mount_flags(args);
2146 #else
2147                 goto out_v4_not_compiled;
2148 #endif /* CONFIG_NFS_V4 */
2149         } else
2150                 nfs_set_mount_transport_protocol(args);
2151
2152         nfs_set_port(sap, &args->nfs_server.port, port);
2153
2154         return nfs_parse_devname(dev_name,
2155                                    &args->nfs_server.hostname,
2156                                    max_namelen,
2157                                    &args->nfs_server.export_path,
2158                                    max_pathlen);
2159
2160 #if !IS_ENABLED(CONFIG_NFS_V4)
2161 out_v4_not_compiled:
2162         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2163         return -EPROTONOSUPPORT;
2164 #else
2165 out_invalid_transport_udp:
2166         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2167         return -EINVAL;
2168 #endif /* !CONFIG_NFS_V4 */
2169
2170 out_no_address:
2171         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2172         return -EINVAL;
2173 }
2174
2175 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
2176                 | NFS_MOUNT_SECURE \
2177                 | NFS_MOUNT_TCP \
2178                 | NFS_MOUNT_VER3 \
2179                 | NFS_MOUNT_KERBEROS \
2180                 | NFS_MOUNT_NONLM \
2181                 | NFS_MOUNT_BROKEN_SUID \
2182                 | NFS_MOUNT_STRICTLOCK \
2183                 | NFS_MOUNT_LEGACY_INTERFACE)
2184
2185 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
2186                 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
2187
2188 static int
2189 nfs_compare_remount_data(struct nfs_server *nfss,
2190                          struct nfs_parsed_mount_data *data)
2191 {
2192         if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
2193             data->rsize != nfss->rsize ||
2194             data->wsize != nfss->wsize ||
2195             data->version != nfss->nfs_client->rpc_ops->version ||
2196             data->minorversion != nfss->nfs_client->cl_minorversion ||
2197             data->retrans != nfss->client->cl_timeout->to_retries ||
2198             !nfs_auth_info_match(&data->auth_info, nfss->client->cl_auth->au_flavor) ||
2199             data->acregmin != nfss->acregmin / HZ ||
2200             data->acregmax != nfss->acregmax / HZ ||
2201             data->acdirmin != nfss->acdirmin / HZ ||
2202             data->acdirmax != nfss->acdirmax / HZ ||
2203             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2204             data->nfs_server.port != nfss->port ||
2205             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2206             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2207                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2208                 return -EINVAL;
2209
2210         return 0;
2211 }
2212
2213 int
2214 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2215 {
2216         int error;
2217         struct nfs_server *nfss = sb->s_fs_info;
2218         struct nfs_parsed_mount_data *data;
2219         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2220         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2221         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2222
2223         sync_filesystem(sb);
2224
2225         /*
2226          * Userspace mount programs that send binary options generally send
2227          * them populated with default values. We have no way to know which
2228          * ones were explicitly specified. Fall back to legacy behavior and
2229          * just return success.
2230          */
2231         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2232             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2233                                            options->version <= 6))))
2234                 return 0;
2235
2236         data = kzalloc(sizeof(*data), GFP_KERNEL);
2237         if (data == NULL)
2238                 return -ENOMEM;
2239
2240         /* fill out struct with values from existing mount */
2241         data->flags = nfss->flags;
2242         data->rsize = nfss->rsize;
2243         data->wsize = nfss->wsize;
2244         data->retrans = nfss->client->cl_timeout->to_retries;
2245         data->selected_flavor = nfss->client->cl_auth->au_flavor;
2246         data->acregmin = nfss->acregmin / HZ;
2247         data->acregmax = nfss->acregmax / HZ;
2248         data->acdirmin = nfss->acdirmin / HZ;
2249         data->acdirmax = nfss->acdirmax / HZ;
2250         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2251         data->nfs_server.port = nfss->port;
2252         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2253         data->version = nfsvers;
2254         data->minorversion = nfss->nfs_client->cl_minorversion;
2255         data->net = current->nsproxy->net_ns;
2256         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2257                 data->nfs_server.addrlen);
2258
2259         /* overwrite those values with any that were specified */
2260         error = -EINVAL;
2261         if (!nfs_parse_mount_options((char *)options, data))
2262                 goto out;
2263
2264         /*
2265          * noac is a special case. It implies -o sync, but that's not
2266          * necessarily reflected in the mtab options. do_remount_sb
2267          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2268          * remount options, so we have to explicitly reset it.
2269          */
2270         if (data->flags & NFS_MOUNT_NOAC)
2271                 *flags |= MS_SYNCHRONOUS;
2272
2273         /* compare new mount options with old ones */
2274         error = nfs_compare_remount_data(nfss, data);
2275 out:
2276         kfree(data);
2277         return error;
2278 }
2279 EXPORT_SYMBOL_GPL(nfs_remount);
2280
2281 /*
2282  * Initialise the common bits of the superblock
2283  */
2284 inline void nfs_initialise_sb(struct super_block *sb)
2285 {
2286         struct nfs_server *server = NFS_SB(sb);
2287
2288         sb->s_magic = NFS_SUPER_MAGIC;
2289
2290         /* We probably want something more informative here */
2291         snprintf(sb->s_id, sizeof(sb->s_id),
2292                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2293
2294         if (sb->s_blocksize == 0)
2295                 sb->s_blocksize = nfs_block_bits(server->wsize,
2296                                                  &sb->s_blocksize_bits);
2297
2298         sb->s_bdi = &server->backing_dev_info;
2299
2300         nfs_super_set_maxbytes(sb, server->maxfilesize);
2301 }
2302
2303 /*
2304  * Finish setting up an NFS2/3 superblock
2305  */
2306 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2307 {
2308         struct nfs_parsed_mount_data *data = mount_info->parsed;
2309         struct nfs_server *server = NFS_SB(sb);
2310
2311         sb->s_blocksize_bits = 0;
2312         sb->s_blocksize = 0;
2313         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2314         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2315         if (data && data->bsize)
2316                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2317
2318         if (server->nfs_client->rpc_ops->version != 2) {
2319                 /* The VFS shouldn't apply the umask to mode bits. We will do
2320                  * so ourselves when necessary.
2321                  */
2322                 sb->s_flags |= MS_POSIXACL;
2323                 sb->s_time_gran = 1;
2324         }
2325
2326         nfs_initialise_sb(sb);
2327 }
2328 EXPORT_SYMBOL_GPL(nfs_fill_super);
2329
2330 /*
2331  * Finish setting up a cloned NFS2/3/4 superblock
2332  */
2333 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2334 {
2335         const struct super_block *old_sb = mount_info->cloned->sb;
2336         struct nfs_server *server = NFS_SB(sb);
2337
2338         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2339         sb->s_blocksize = old_sb->s_blocksize;
2340         sb->s_maxbytes = old_sb->s_maxbytes;
2341         sb->s_xattr = old_sb->s_xattr;
2342         sb->s_op = old_sb->s_op;
2343         sb->s_time_gran = 1;
2344
2345         if (server->nfs_client->rpc_ops->version != 2) {
2346                 /* The VFS shouldn't apply the umask to mode bits. We will do
2347                  * so ourselves when necessary.
2348                  */
2349                 sb->s_flags |= MS_POSIXACL;
2350         }
2351
2352         nfs_initialise_sb(sb);
2353 }
2354
2355 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2356 {
2357         const struct nfs_server *a = s->s_fs_info;
2358         const struct rpc_clnt *clnt_a = a->client;
2359         const struct rpc_clnt *clnt_b = b->client;
2360
2361         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2362                 goto Ebusy;
2363         if (a->nfs_client != b->nfs_client)
2364                 goto Ebusy;
2365         if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
2366                 goto Ebusy;
2367         if (a->wsize != b->wsize)
2368                 goto Ebusy;
2369         if (a->rsize != b->rsize)
2370                 goto Ebusy;
2371         if (a->acregmin != b->acregmin)
2372                 goto Ebusy;
2373         if (a->acregmax != b->acregmax)
2374                 goto Ebusy;
2375         if (a->acdirmin != b->acdirmin)
2376                 goto Ebusy;
2377         if (a->acdirmax != b->acdirmax)
2378                 goto Ebusy;
2379         if (b->auth_info.flavor_len > 0 &&
2380            clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2381                 goto Ebusy;
2382         return 1;
2383 Ebusy:
2384         return 0;
2385 }
2386
2387 struct nfs_sb_mountdata {
2388         struct nfs_server *server;
2389         int mntflags;
2390 };
2391
2392 static int nfs_set_super(struct super_block *s, void *data)
2393 {
2394         struct nfs_sb_mountdata *sb_mntdata = data;
2395         struct nfs_server *server = sb_mntdata->server;
2396         int ret;
2397
2398         s->s_flags = sb_mntdata->mntflags;
2399         s->s_fs_info = server;
2400         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2401         ret = set_anon_super(s, server);
2402         if (ret == 0)
2403                 server->s_dev = s->s_dev;
2404         return ret;
2405 }
2406
2407 static int nfs_compare_super_address(struct nfs_server *server1,
2408                                      struct nfs_server *server2)
2409 {
2410         struct sockaddr *sap1, *sap2;
2411
2412         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2413         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2414
2415         if (sap1->sa_family != sap2->sa_family)
2416                 return 0;
2417
2418         switch (sap1->sa_family) {
2419         case AF_INET: {
2420                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2421                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2422                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2423                         return 0;
2424                 if (sin1->sin_port != sin2->sin_port)
2425                         return 0;
2426                 break;
2427         }
2428         case AF_INET6: {
2429                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2430                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2431                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2432                         return 0;
2433                 if (sin1->sin6_port != sin2->sin6_port)
2434                         return 0;
2435                 break;
2436         }
2437         default:
2438                 return 0;
2439         }
2440
2441         return 1;
2442 }
2443
2444 static int nfs_compare_super(struct super_block *sb, void *data)
2445 {
2446         struct nfs_sb_mountdata *sb_mntdata = data;
2447         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2448         int mntflags = sb_mntdata->mntflags;
2449
2450         if (!nfs_compare_super_address(old, server))
2451                 return 0;
2452         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2453         if (old->flags & NFS_MOUNT_UNSHARED)
2454                 return 0;
2455         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2456                 return 0;
2457         return nfs_compare_mount_options(sb, server, mntflags);
2458 }
2459
2460 #ifdef CONFIG_NFS_FSCACHE
2461 static void nfs_get_cache_cookie(struct super_block *sb,
2462                                  struct nfs_parsed_mount_data *parsed,
2463                                  struct nfs_clone_mount *cloned)
2464 {
2465         struct nfs_server *nfss = NFS_SB(sb);
2466         char *uniq = NULL;
2467         int ulen = 0;
2468
2469         nfss->fscache_key = NULL;
2470         nfss->fscache = NULL;
2471
2472         if (parsed) {
2473                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2474                         return;
2475                 if (parsed->fscache_uniq) {
2476                         uniq = parsed->fscache_uniq;
2477                         ulen = strlen(parsed->fscache_uniq);
2478                 }
2479         } else if (cloned) {
2480                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2481                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2482                         return;
2483                 if (mnt_s->fscache_key) {
2484                         uniq = mnt_s->fscache_key->key.uniquifier;
2485                         ulen = mnt_s->fscache_key->key.uniq_len;
2486                 };
2487         } else
2488                 return;
2489
2490         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2491 }
2492 #else
2493 static void nfs_get_cache_cookie(struct super_block *sb,
2494                                  struct nfs_parsed_mount_data *parsed,
2495                                  struct nfs_clone_mount *cloned)
2496 {
2497 }
2498 #endif
2499
2500 static int nfs_bdi_register(struct nfs_server *server)
2501 {
2502         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2503 }
2504
2505 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2506                         struct nfs_mount_info *mount_info)
2507 {
2508         int error;
2509         unsigned long kflags = 0, kflags_out = 0;
2510         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2511                 kflags |= SECURITY_LSM_NATIVE_LABELS;
2512
2513         error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
2514                                                 kflags, &kflags_out);
2515         if (error)
2516                 goto err;
2517
2518         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2519                 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2520                 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2521 err:
2522         return error;
2523 }
2524 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2525
2526 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2527                           struct nfs_mount_info *mount_info)
2528 {
2529         /* clone any lsm security options from the parent to the new sb */
2530         if (d_inode(mntroot)->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2531                 return -ESTALE;
2532         return security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2533 }
2534 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2535
2536 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2537                                    int flags, const char *dev_name,
2538                                    struct nfs_mount_info *mount_info,
2539                                    struct nfs_subversion *nfs_mod)
2540 {
2541         struct super_block *s;
2542         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2543         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2544         struct nfs_sb_mountdata sb_mntdata = {
2545                 .mntflags = flags,
2546                 .server = server,
2547         };
2548         int error;
2549
2550         if (server->flags & NFS_MOUNT_UNSHARED)
2551                 compare_super = NULL;
2552
2553         /* -o noac implies -o sync */
2554         if (server->flags & NFS_MOUNT_NOAC)
2555                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2556
2557         if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
2558                 if (mount_info->cloned->sb->s_flags & MS_SYNCHRONOUS)
2559                         sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2560
2561         /* Get a superblock - note that we may end up sharing one that already exists */
2562         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2563         if (IS_ERR(s)) {
2564                 mntroot = ERR_CAST(s);
2565                 goto out_err_nosb;
2566         }
2567
2568         if (s->s_fs_info != server) {
2569                 nfs_free_server(server);
2570                 server = NULL;
2571         } else {
2572                 error = nfs_bdi_register(server);
2573                 if (error) {
2574                         mntroot = ERR_PTR(error);
2575                         goto error_splat_super;
2576                 }
2577                 server->super = s;
2578         }
2579
2580         if (!s->s_root) {
2581                 /* initial superblock/root creation */
2582                 mount_info->fill_super(s, mount_info);
2583                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2584         }
2585
2586         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2587         if (IS_ERR(mntroot))
2588                 goto error_splat_super;
2589
2590         error = mount_info->set_security(s, mntroot, mount_info);
2591         if (error)
2592                 goto error_splat_root;
2593
2594         s->s_flags |= MS_ACTIVE;
2595
2596 out:
2597         return mntroot;
2598
2599 out_err_nosb:
2600         nfs_free_server(server);
2601         goto out;
2602
2603 error_splat_root:
2604         dput(mntroot);
2605         mntroot = ERR_PTR(error);
2606 error_splat_super:
2607         deactivate_locked_super(s);
2608         goto out;
2609 }
2610 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2611
2612 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2613         int flags, const char *dev_name, void *raw_data)
2614 {
2615         struct nfs_mount_info mount_info = {
2616                 .fill_super = nfs_fill_super,
2617                 .set_security = nfs_set_sb_security,
2618         };
2619         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2620         struct nfs_subversion *nfs_mod;
2621         int error;
2622
2623         mount_info.parsed = nfs_alloc_parsed_mount_data();
2624         mount_info.mntfh = nfs_alloc_fhandle();
2625         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2626                 goto out;
2627
2628         /* Validate the mount data */
2629         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2630         if (error == NFS_TEXT_DATA)
2631                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2632         if (error < 0) {
2633                 mntroot = ERR_PTR(error);
2634                 goto out;
2635         }
2636
2637         nfs_mod = get_nfs_version(mount_info.parsed->version);
2638         if (IS_ERR(nfs_mod)) {
2639                 mntroot = ERR_CAST(nfs_mod);
2640                 goto out;
2641         }
2642
2643         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2644
2645         put_nfs_version(nfs_mod);
2646 out:
2647         nfs_free_parsed_mount_data(mount_info.parsed);
2648         nfs_free_fhandle(mount_info.mntfh);
2649         return mntroot;
2650 }
2651 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2652
2653 /*
2654  * Destroy an NFS2/3 superblock
2655  */
2656 void nfs_kill_super(struct super_block *s)
2657 {
2658         struct nfs_server *server = NFS_SB(s);
2659         dev_t dev = s->s_dev;
2660
2661         generic_shutdown_super(s);
2662
2663         nfs_fscache_release_super_cookie(s);
2664
2665         nfs_free_server(server);
2666         free_anon_bdev(dev);
2667 }
2668 EXPORT_SYMBOL_GPL(nfs_kill_super);
2669
2670 /*
2671  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2672  */
2673 static struct dentry *
2674 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2675                 const char *dev_name, void *raw_data)
2676 {
2677         struct nfs_clone_mount *data = raw_data;
2678         struct nfs_mount_info mount_info = {
2679                 .fill_super = nfs_clone_super,
2680                 .set_security = nfs_clone_sb_security,
2681                 .cloned = data,
2682         };
2683         struct nfs_server *server;
2684         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2685         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2686
2687         dprintk("--> nfs_xdev_mount()\n");
2688
2689         mount_info.mntfh = mount_info.cloned->fh;
2690
2691         /* create a new volume representation */
2692         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2693
2694         if (IS_ERR(server))
2695                 mntroot = ERR_CAST(server);
2696         else
2697                 mntroot = nfs_fs_mount_common(server, flags,
2698                                 dev_name, &mount_info, nfs_mod);
2699
2700         dprintk("<-- nfs_xdev_mount() = %ld\n",
2701                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2702         return mntroot;
2703 }
2704
2705 #if IS_ENABLED(CONFIG_NFS_V4)
2706
2707 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2708 {
2709         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2710                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2711 }
2712
2713 /*
2714  * Validate NFSv4 mount options
2715  */
2716 static int nfs4_validate_mount_data(void *options,
2717                                     struct nfs_parsed_mount_data *args,
2718                                     const char *dev_name)
2719 {
2720         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2721         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2722         char *c;
2723
2724         if (data == NULL)
2725                 goto out_no_data;
2726
2727         args->version = 4;
2728
2729         switch (data->version) {
2730         case 1:
2731                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2732                         goto out_no_address;
2733                 if (data->host_addrlen == 0)
2734                         goto out_no_address;
2735                 args->nfs_server.addrlen = data->host_addrlen;
2736                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2737                         return -EFAULT;
2738                 if (!nfs_verify_server_address(sap))
2739                         goto out_no_address;
2740                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2741
2742                 if (data->auth_flavourlen) {
2743                         rpc_authflavor_t pseudoflavor;
2744                         if (data->auth_flavourlen > 1)
2745                                 goto out_inval_auth;
2746                         if (copy_from_user(&pseudoflavor,
2747                                            data->auth_flavours,
2748                                            sizeof(pseudoflavor)))
2749                                 return -EFAULT;
2750                         args->selected_flavor = pseudoflavor;
2751                 } else
2752                         args->selected_flavor = RPC_AUTH_UNIX;
2753
2754                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2755                 if (IS_ERR(c))
2756                         return PTR_ERR(c);
2757                 args->nfs_server.hostname = c;
2758
2759                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2760                 if (IS_ERR(c))
2761                         return PTR_ERR(c);
2762                 args->nfs_server.export_path = c;
2763                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2764
2765                 c = strndup_user(data->client_addr.data, 16);
2766                 if (IS_ERR(c))
2767                         return PTR_ERR(c);
2768                 args->client_address = c;
2769
2770                 /*
2771                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2772                  * can deal with.
2773                  */
2774
2775                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2776                 args->rsize     = data->rsize;
2777                 args->wsize     = data->wsize;
2778                 args->timeo     = data->timeo;
2779                 args->retrans   = data->retrans;
2780                 args->acregmin  = data->acregmin;
2781                 args->acregmax  = data->acregmax;
2782                 args->acdirmin  = data->acdirmin;
2783                 args->acdirmax  = data->acdirmax;
2784                 args->nfs_server.protocol = data->proto;
2785                 nfs_validate_transport_protocol(args);
2786                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2787                         goto out_invalid_transport_udp;
2788
2789                 break;
2790         default:
2791                 return NFS_TEXT_DATA;
2792         }
2793
2794         return 0;
2795
2796 out_no_data:
2797         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2798         return -EINVAL;
2799
2800 out_inval_auth:
2801         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2802                  data->auth_flavourlen);
2803         return -EINVAL;
2804
2805 out_no_address:
2806         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2807         return -EINVAL;
2808
2809 out_invalid_transport_udp:
2810         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2811         return -EINVAL;
2812 }
2813
2814 /*
2815  * NFS v4 module parameters need to stay in the
2816  * NFS client for backwards compatibility
2817  */
2818 unsigned int nfs_callback_set_tcpport;
2819 /* Default cache timeout is 10 minutes */
2820 unsigned int nfs_idmap_cache_timeout = 600;
2821 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2822 bool nfs4_disable_idmapping = true;
2823 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2824 unsigned short send_implementation_id = 1;
2825 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2826 bool recover_lost_locks = false;
2827
2828 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2829 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2830 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2831 EXPORT_SYMBOL_GPL(max_session_slots);
2832 EXPORT_SYMBOL_GPL(send_implementation_id);
2833 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2834 EXPORT_SYMBOL_GPL(recover_lost_locks);
2835
2836 #define NFS_CALLBACK_MAXPORTNR (65535U)
2837
2838 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2839 {
2840         unsigned long num;
2841         int ret;
2842
2843         if (!val)
2844                 return -EINVAL;
2845         ret = kstrtoul(val, 0, &num);
2846         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2847                 return -EINVAL;
2848         *((unsigned int *)kp->arg) = num;
2849         return 0;
2850 }
2851 static const struct kernel_param_ops param_ops_portnr = {
2852         .set = param_set_portnr,
2853         .get = param_get_uint,
2854 };
2855 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2856
2857 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2858 module_param(nfs_idmap_cache_timeout, int, 0644);
2859 module_param(nfs4_disable_idmapping, bool, 0644);
2860 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2861                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2862 MODULE_PARM_DESC(nfs4_disable_idmapping,
2863                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2864 module_param(max_session_slots, ushort, 0644);
2865 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2866                 "requests the client will negotiate");
2867 module_param(send_implementation_id, ushort, 0644);
2868 MODULE_PARM_DESC(send_implementation_id,
2869                 "Send implementation ID with NFSv4.1 exchange_id");
2870 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2871
2872 module_param(recover_lost_locks, bool, 0644);
2873 MODULE_PARM_DESC(recover_lost_locks,
2874                  "If the server reports that a lock might be lost, "
2875                  "try to recover it risking data corruption.");
2876
2877
2878 #endif /* CONFIG_NFS_V4 */