linux/fs/nfs/super.c
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   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
  79enum {
  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
 120static 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
 192enum {
 193        Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
 194        Opt_xprt_rdma6,
 195
 196        Opt_xprt_err
 197};
 198
 199static const match_table_t nfs_xprt_protocol_tokens = {
 200        { Opt_xprt_udp, "udp" },
 201        { Opt_xprt_udp6, "udp6" },
 202        { Opt_xprt_tcp, "tcp" },
 203        { Opt_xprt_tcp6, "tcp6" },
 204        { Opt_xprt_rdma, "rdma" },
 205        { Opt_xprt_rdma6, "rdma6" },
 206
 207        { Opt_xprt_err, NULL }
 208};
 209
 210enum {
 211        Opt_sec_none, Opt_sec_sys,
 212        Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 213        Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 214        Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 215
 216        Opt_sec_err
 217};
 218
 219static const match_table_t nfs_secflavor_tokens = {
 220        { Opt_sec_none, "none" },
 221        { Opt_sec_none, "null" },
 222        { Opt_sec_sys, "sys" },
 223
 224        { Opt_sec_krb5, "krb5" },
 225        { Opt_sec_krb5i, "krb5i" },
 226        { Opt_sec_krb5p, "krb5p" },
 227
 228        { Opt_sec_lkey, "lkey" },
 229        { Opt_sec_lkeyi, "lkeyi" },
 230        { Opt_sec_lkeyp, "lkeyp" },
 231
 232        { Opt_sec_spkm, "spkm3" },
 233        { Opt_sec_spkmi, "spkm3i" },
 234        { Opt_sec_spkmp, "spkm3p" },
 235
 236        { Opt_sec_err, NULL }
 237};
 238
 239enum {
 240        Opt_lookupcache_all, Opt_lookupcache_positive,
 241        Opt_lookupcache_none,
 242
 243        Opt_lookupcache_err
 244};
 245
 246static match_table_t nfs_lookupcache_tokens = {
 247        { Opt_lookupcache_all, "all" },
 248        { Opt_lookupcache_positive, "pos" },
 249        { Opt_lookupcache_positive, "positive" },
 250        { Opt_lookupcache_none, "none" },
 251
 252        { Opt_lookupcache_err, NULL }
 253};
 254
 255enum {
 256        Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 257        Opt_local_lock_none,
 258
 259        Opt_local_lock_err
 260};
 261
 262static match_table_t nfs_local_lock_tokens = {
 263        { Opt_local_lock_all, "all" },
 264        { Opt_local_lock_flock, "flock" },
 265        { Opt_local_lock_posix, "posix" },
 266        { Opt_local_lock_none, "none" },
 267
 268        { Opt_local_lock_err, NULL }
 269};
 270
 271enum {
 272        Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 273        Opt_vers_4_1, Opt_vers_4_2,
 274
 275        Opt_vers_err
 276};
 277
 278static match_table_t nfs_vers_tokens = {
 279        { Opt_vers_2, "2" },
 280        { Opt_vers_3, "3" },
 281        { Opt_vers_4, "4" },
 282        { Opt_vers_4_0, "4.0" },
 283        { Opt_vers_4_1, "4.1" },
 284        { Opt_vers_4_2, "4.2" },
 285
 286        { Opt_vers_err, NULL }
 287};
 288
 289static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 290                int flags, const char *dev_name, void *raw_data);
 291
 292struct file_system_type nfs_fs_type = {
 293        .owner          = THIS_MODULE,
 294        .name           = "nfs",
 295        .mount          = nfs_fs_mount,
 296        .kill_sb        = nfs_kill_super,
 297        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 298};
 299MODULE_ALIAS_FS("nfs");
 300EXPORT_SYMBOL_GPL(nfs_fs_type);
 301
 302struct file_system_type nfs_xdev_fs_type = {
 303        .owner          = THIS_MODULE,
 304        .name           = "nfs",
 305        .mount          = nfs_xdev_mount,
 306        .kill_sb        = nfs_kill_super,
 307        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 308};
 309
 310const struct super_operations nfs_sops = {
 311        .alloc_inode    = nfs_alloc_inode,
 312        .destroy_inode  = nfs_destroy_inode,
 313        .write_inode    = nfs_write_inode,
 314        .drop_inode     = nfs_drop_inode,
 315        .statfs         = nfs_statfs,
 316        .evict_inode    = nfs_evict_inode,
 317        .umount_begin   = nfs_umount_begin,
 318        .show_options   = nfs_show_options,
 319        .show_devname   = nfs_show_devname,
 320        .show_path      = nfs_show_path,
 321        .show_stats     = nfs_show_stats,
 322        .remount_fs     = nfs_remount,
 323};
 324EXPORT_SYMBOL_GPL(nfs_sops);
 325
 326#if IS_ENABLED(CONFIG_NFS_V4)
 327static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 328static int nfs4_validate_mount_data(void *options,
 329        struct nfs_parsed_mount_data *args, const char *dev_name);
 330
 331struct file_system_type nfs4_fs_type = {
 332        .owner          = THIS_MODULE,
 333        .name           = "nfs4",
 334        .mount          = nfs_fs_mount,
 335        .kill_sb        = nfs_kill_super,
 336        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
 337};
 338MODULE_ALIAS_FS("nfs4");
 339MODULE_ALIAS("nfs4");
 340EXPORT_SYMBOL_GPL(nfs4_fs_type);
 341
 342static int __init register_nfs4_fs(void)
 343{
 344        return register_filesystem(&nfs4_fs_type);
 345}
 346
 347static void unregister_nfs4_fs(void)
 348{
 349        unregister_filesystem(&nfs4_fs_type);
 350}
 351#else
 352static int __init register_nfs4_fs(void)
 353{
 354        return 0;
 355}
 356
 357static void unregister_nfs4_fs(void)
 358{
 359}
 360#endif
 361
 362static struct shrinker acl_shrinker = {
 363        .count_objects  = nfs_access_cache_count,
 364        .scan_objects   = nfs_access_cache_scan,
 365        .seeks          = DEFAULT_SEEKS,
 366};
 367
 368/*
 369 * Register the NFS filesystems
 370 */
 371int __init register_nfs_fs(void)
 372{
 373        int ret;
 374
 375        ret = register_filesystem(&nfs_fs_type);
 376        if (ret < 0)
 377                goto error_0;
 378
 379        ret = register_nfs4_fs();
 380        if (ret < 0)
 381                goto error_1;
 382
 383        ret = nfs_register_sysctl();
 384        if (ret < 0)
 385                goto error_2;
 386        ret = register_shrinker(&acl_shrinker);
 387        if (ret < 0)
 388                goto error_3;
 389        return 0;
 390error_3:
 391        nfs_unregister_sysctl();
 392error_2:
 393        unregister_nfs4_fs();
 394error_1:
 395        unregister_filesystem(&nfs_fs_type);
 396error_0:
 397        return ret;
 398}
 399
 400/*
 401 * Unregister the NFS filesystems
 402 */
 403void __exit unregister_nfs_fs(void)
 404{
 405        unregister_shrinker(&acl_shrinker);
 406        nfs_unregister_sysctl();
 407        unregister_nfs4_fs();
 408        unregister_filesystem(&nfs_fs_type);
 409}
 410
 411bool nfs_sb_active(struct super_block *sb)
 412{
 413        struct nfs_server *server = NFS_SB(sb);
 414
 415        if (!atomic_inc_not_zero(&sb->s_active))
 416                return false;
 417        if (atomic_inc_return(&server->active) != 1)
 418                atomic_dec(&sb->s_active);
 419        return true;
 420}
 421EXPORT_SYMBOL_GPL(nfs_sb_active);
 422
 423void nfs_sb_deactive(struct super_block *sb)
 424{
 425        struct nfs_server *server = NFS_SB(sb);
 426
 427        if (atomic_dec_and_test(&server->active))
 428                deactivate_super(sb);
 429}
 430EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 431
 432/*
 433 * Deliver file system statistics to userspace
 434 */
 435int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 436{
 437        struct nfs_server *server = NFS_SB(dentry->d_sb);
 438        unsigned char blockbits;
 439        unsigned long blockres;
 440        struct nfs_fh *fh = NFS_FH(d_inode(dentry));
 441        struct nfs_fsstat res;
 442        int error = -ENOMEM;
 443
 444        res.fattr = nfs_alloc_fattr();
 445        if (res.fattr == NULL)
 446                goto out_err;
 447
 448        error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 449        if (unlikely(error == -ESTALE)) {
 450                struct dentry *pd_dentry;
 451
 452                pd_dentry = dget_parent(dentry);
 453                if (pd_dentry != NULL) {
 454                        nfs_zap_caches(d_inode(pd_dentry));
 455                        dput(pd_dentry);
 456                }
 457        }
 458        nfs_free_fattr(res.fattr);
 459        if (error < 0)
 460                goto out_err;
 461
 462        buf->f_type = NFS_SUPER_MAGIC;
 463
 464        /*
 465         * Current versions of glibc do not correctly handle the
 466         * case where f_frsize != f_bsize.  Eventually we want to
 467         * report the value of wtmult in this field.
 468         */
 469        buf->f_frsize = dentry->d_sb->s_blocksize;
 470
 471        /*
 472         * On most *nix systems, f_blocks, f_bfree, and f_bavail
 473         * are reported in units of f_frsize.  Linux hasn't had
 474         * an f_frsize field in its statfs struct until recently,
 475         * thus historically Linux's sys_statfs reports these
 476         * fields in units of f_bsize.
 477         */
 478        buf->f_bsize = dentry->d_sb->s_blocksize;
 479        blockbits = dentry->d_sb->s_blocksize_bits;
 480        blockres = (1 << blockbits) - 1;
 481        buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 482        buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 483        buf->f_bavail = (res.abytes + blockres) >> blockbits;
 484
 485        buf->f_files = res.tfiles;
 486        buf->f_ffree = res.afiles;
 487
 488        buf->f_namelen = server->namelen;
 489
 490        return 0;
 491
 492 out_err:
 493        dprintk("%s: statfs error = %d\n", __func__, -error);
 494        return error;
 495}
 496EXPORT_SYMBOL_GPL(nfs_statfs);
 497
 498/*
 499 * Map the security flavour number to a name
 500 */
 501static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 502{
 503        static const struct {
 504                rpc_authflavor_t flavour;
 505                const char *str;
 506        } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
 507                /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
 508                { RPC_AUTH_NULL, "null" },
 509                { RPC_AUTH_UNIX, "sys" },
 510                { RPC_AUTH_GSS_KRB5, "krb5" },
 511                { RPC_AUTH_GSS_KRB5I, "krb5i" },
 512                { RPC_AUTH_GSS_KRB5P, "krb5p" },
 513                { RPC_AUTH_GSS_LKEY, "lkey" },
 514                { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 515                { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 516                { RPC_AUTH_GSS_SPKM, "spkm" },
 517                { RPC_AUTH_GSS_SPKMI, "spkmi" },
 518                { RPC_AUTH_GSS_SPKMP, "spkmp" },
 519                { UINT_MAX, "unknown" }
 520        };
 521        int i;
 522
 523        for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 524                if (sec_flavours[i].flavour == flavour)
 525                        break;
 526        }
 527        return sec_flavours[i].str;
 528}
 529
 530static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 531                                  int showdefaults)
 532{
 533        struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 534
 535        seq_printf(m, ",mountproto=");
 536        switch (sap->sa_family) {
 537        case AF_INET:
 538                switch (nfss->mountd_protocol) {
 539                case IPPROTO_UDP:
 540                        seq_printf(m, RPCBIND_NETID_UDP);
 541                        break;
 542                case IPPROTO_TCP:
 543                        seq_printf(m, RPCBIND_NETID_TCP);
 544                        break;
 545                default:
 546                        if (showdefaults)
 547                                seq_printf(m, "auto");
 548                }
 549                break;
 550        case AF_INET6:
 551                switch (nfss->mountd_protocol) {
 552                case IPPROTO_UDP:
 553                        seq_printf(m, RPCBIND_NETID_UDP6);
 554                        break;
 555                case IPPROTO_TCP:
 556                        seq_printf(m, RPCBIND_NETID_TCP6);
 557                        break;
 558                default:
 559                        if (showdefaults)
 560                                seq_printf(m, "auto");
 561                }
 562                break;
 563        default:
 564                if (showdefaults)
 565                        seq_printf(m, "auto");
 566        }
 567}
 568
 569static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 570                                    int showdefaults)
 571{
 572        struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 573
 574        if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 575                return;
 576
 577        switch (sap->sa_family) {
 578        case AF_INET: {
 579                struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 580                seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 581                break;
 582        }
 583        case AF_INET6: {
 584                struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 585                seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 586                break;
 587        }
 588        default:
 589                if (showdefaults)
 590                        seq_printf(m, ",mountaddr=unspecified");
 591        }
 592
 593        if (nfss->mountd_version || showdefaults)
 594                seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 595        if ((nfss->mountd_port &&
 596                nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 597                showdefaults)
 598                seq_printf(m, ",mountport=%u", nfss->mountd_port);
 599
 600        nfs_show_mountd_netid(m, nfss, showdefaults);
 601}
 602
 603#if IS_ENABLED(CONFIG_NFS_V4)
 604static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 605                                    int showdefaults)
 606{
 607        struct nfs_client *clp = nfss->nfs_client;
 608
 609        seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 610}
 611#else
 612static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 613                                    int showdefaults)
 614{
 615}
 616#endif
 617
 618static void nfs_show_nfs_version(struct seq_file *m,
 619                unsigned int version,
 620                unsigned int minorversion)
 621{
 622        seq_printf(m, ",vers=%u", version);
 623        if (version == 4)
 624                seq_printf(m, ".%u", minorversion);
 625}
 626
 627/*
 628 * Describe the mount options in force on this server representation
 629 */
 630static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 631                                   int showdefaults)
 632{
 633        static const struct proc_nfs_info {
 634                int flag;
 635                const char *str;
 636                const char *nostr;
 637        } nfs_info[] = {
 638                { NFS_MOUNT_SOFT, ",soft", ",hard" },
 639                { NFS_MOUNT_POSIX, ",posix", "" },
 640                { NFS_MOUNT_NOCTO, ",nocto", "" },
 641                { NFS_MOUNT_NOAC, ",noac", "" },
 642                { NFS_MOUNT_NONLM, ",nolock", "" },
 643                { NFS_MOUNT_NOACL, ",noacl", "" },
 644                { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 645                { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 646                { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 647                { 0, NULL, NULL }
 648        };
 649        const struct proc_nfs_info *nfs_infop;
 650        struct nfs_client *clp = nfss->nfs_client;
 651        u32 version = clp->rpc_ops->version;
 652        int local_flock, local_fcntl;
 653
 654        nfs_show_nfs_version(m, version, clp->cl_minorversion);
 655        seq_printf(m, ",rsize=%u", nfss->rsize);
 656        seq_printf(m, ",wsize=%u", nfss->wsize);
 657        if (nfss->bsize != 0)
 658                seq_printf(m, ",bsize=%u", nfss->bsize);
 659        seq_printf(m, ",namlen=%u", nfss->namelen);
 660        if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 661                seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 662        if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 663                seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 664        if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 665                seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 666        if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 667                seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 668        for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 669                if (nfss->flags & nfs_infop->flag)
 670                        seq_puts(m, nfs_infop->str);
 671                else
 672                        seq_puts(m, nfs_infop->nostr);
 673        }
 674        rcu_read_lock();
 675        seq_printf(m, ",proto=%s",
 676                   rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 677        rcu_read_unlock();
 678        if (version == 4) {
 679                if (nfss->port != NFS_PORT)
 680                        seq_printf(m, ",port=%u", nfss->port);
 681        } else
 682                if (nfss->port)
 683                        seq_printf(m, ",port=%u", nfss->port);
 684
 685        seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 686        seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 687        seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 688
 689        if (version != 4)
 690                nfs_show_mountd_options(m, nfss, showdefaults);
 691        else
 692                nfs_show_nfsv4_options(m, nfss, showdefaults);
 693
 694        if (nfss->options & NFS_OPTION_FSCACHE)
 695                seq_printf(m, ",fsc");
 696
 697        if (nfss->options & NFS_OPTION_MIGRATION)
 698                seq_printf(m, ",migration");
 699
 700        if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 701                if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 702                        seq_printf(m, ",lookupcache=none");
 703                else
 704                        seq_printf(m, ",lookupcache=pos");
 705        }
 706
 707        local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 708        local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 709
 710        if (!local_flock && !local_fcntl)
 711                seq_printf(m, ",local_lock=none");
 712        else if (local_flock && local_fcntl)
 713                seq_printf(m, ",local_lock=all");
 714        else if (local_flock)
 715                seq_printf(m, ",local_lock=flock");
 716        else
 717                seq_printf(m, ",local_lock=posix");
 718}
 719
 720/*
 721 * Describe the mount options on this VFS mountpoint
 722 */
 723int nfs_show_options(struct seq_file *m, struct dentry *root)
 724{
 725        struct nfs_server *nfss = NFS_SB(root->d_sb);
 726
 727        nfs_show_mount_options(m, nfss, 0);
 728
 729        rcu_read_lock();
 730        seq_printf(m, ",addr=%s",
 731                        rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 732                                                        RPC_DISPLAY_ADDR));
 733        rcu_read_unlock();
 734
 735        return 0;
 736}
 737EXPORT_SYMBOL_GPL(nfs_show_options);
 738
 739#if IS_ENABLED(CONFIG_NFS_V4)
 740#ifdef CONFIG_NFS_V4_1
 741static void show_sessions(struct seq_file *m, struct nfs_server *server)
 742{
 743        if (nfs4_has_session(server->nfs_client))
 744                seq_printf(m, ",sessions");
 745}
 746#else
 747static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 748#endif
 749#endif
 750
 751#ifdef CONFIG_NFS_V4_1
 752static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 753{
 754        seq_printf(m, ",pnfs=");
 755        if (server->pnfs_curr_ld)
 756                seq_printf(m, "%s", server->pnfs_curr_ld->name);
 757        else
 758                seq_printf(m, "not configured");
 759}
 760
 761static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 762{
 763        if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 764                struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 765                seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 766                           "date='%llu,%u'",
 767                           impl_id->name, impl_id->domain,
 768                           impl_id->date.seconds, impl_id->date.nseconds);
 769        }
 770}
 771#else
 772#if IS_ENABLED(CONFIG_NFS_V4)
 773static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 774{
 775}
 776#endif
 777static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 778{
 779}
 780#endif
 781
 782int nfs_show_devname(struct seq_file *m, struct dentry *root)
 783{
 784        char *page = (char *) __get_free_page(GFP_KERNEL);
 785        char *devname, *dummy;
 786        int err = 0;
 787        if (!page)
 788                return -ENOMEM;
 789        devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 790        if (IS_ERR(devname))
 791                err = PTR_ERR(devname);
 792        else
 793                seq_escape(m, devname, " \t\n\\");
 794        free_page((unsigned long)page);
 795        return err;
 796}
 797EXPORT_SYMBOL_GPL(nfs_show_devname);
 798
 799int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 800{
 801        seq_puts(m, "/");
 802        return 0;
 803}
 804EXPORT_SYMBOL_GPL(nfs_show_path);
 805
 806/*
 807 * Present statistical information for this VFS mountpoint
 808 */
 809int nfs_show_stats(struct seq_file *m, struct dentry *root)
 810{
 811        int i, cpu;
 812        struct nfs_server *nfss = NFS_SB(root->d_sb);
 813        struct rpc_auth *auth = nfss->client->cl_auth;
 814        struct nfs_iostats totals = { };
 815
 816        seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 817
 818        /*
 819         * Display all mount option settings
 820         */
 821        seq_printf(m, "\n\topts:\t");
 822        seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 823        seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 824        seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 825        seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 826        nfs_show_mount_options(m, nfss, 1);
 827
 828        seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 829
 830        show_implementation_id(m, nfss);
 831
 832        seq_printf(m, "\n\tcaps:\t");
 833        seq_printf(m, "caps=0x%x", nfss->caps);
 834        seq_printf(m, ",wtmult=%u", nfss->wtmult);
 835        seq_printf(m, ",dtsize=%u", nfss->dtsize);
 836        seq_printf(m, ",bsize=%u", nfss->bsize);
 837        seq_printf(m, ",namlen=%u", nfss->namelen);
 838
 839#if IS_ENABLED(CONFIG_NFS_V4)
 840        if (nfss->nfs_client->rpc_ops->version == 4) {
 841                seq_printf(m, "\n\tnfsv4:\t");
 842                seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 843                seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 844                seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
 845                seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 846                show_sessions(m, nfss);
 847                show_pnfs(m, nfss);
 848        }
 849#endif
 850
 851        /*
 852         * Display security flavor in effect for this mount
 853         */
 854        seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 855        if (auth->au_flavor)
 856                seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 857
 858        /*
 859         * Display superblock I/O counters
 860         */
 861        for_each_possible_cpu(cpu) {
 862                struct nfs_iostats *stats;
 863
 864                preempt_disable();
 865                stats = per_cpu_ptr(nfss->io_stats, cpu);
 866
 867                for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 868                        totals.events[i] += stats->events[i];
 869                for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 870                        totals.bytes[i] += stats->bytes[i];
 871#ifdef CONFIG_NFS_FSCACHE
 872                for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 873                        totals.fscache[i] += stats->fscache[i];
 874#endif
 875
 876                preempt_enable();
 877        }
 878
 879        seq_printf(m, "\n\tevents:\t");
 880        for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 881                seq_printf(m, "%lu ", totals.events[i]);
 882        seq_printf(m, "\n\tbytes:\t");
 883        for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 884                seq_printf(m, "%Lu ", totals.bytes[i]);
 885#ifdef CONFIG_NFS_FSCACHE
 886        if (nfss->options & NFS_OPTION_FSCACHE) {
 887                seq_printf(m, "\n\tfsc:\t");
 888                for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 889                        seq_printf(m, "%Lu ", totals.bytes[i]);
 890        }
 891#endif
 892        seq_printf(m, "\n");
 893
 894        rpc_print_iostats(m, nfss->client);
 895
 896        return 0;
 897}
 898EXPORT_SYMBOL_GPL(nfs_show_stats);
 899
 900/*
 901 * Begin unmount by attempting to remove all automounted mountpoints we added
 902 * in response to xdev traversals and referrals
 903 */
 904void nfs_umount_begin(struct super_block *sb)
 905{
 906        struct nfs_server *server;
 907        struct rpc_clnt *rpc;
 908
 909        server = NFS_SB(sb);
 910        /* -EIO all pending I/O */
 911        rpc = server->client_acl;
 912        if (!IS_ERR(rpc))
 913                rpc_killall_tasks(rpc);
 914        rpc = server->client;
 915        if (!IS_ERR(rpc))
 916                rpc_killall_tasks(rpc);
 917}
 918EXPORT_SYMBOL_GPL(nfs_umount_begin);
 919
 920static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 921{
 922        struct nfs_parsed_mount_data *data;
 923
 924        data = kzalloc(sizeof(*data), GFP_KERNEL);
 925        if (data) {
 926                data->timeo             = NFS_UNSPEC_TIMEO;
 927                data->retrans           = NFS_UNSPEC_RETRANS;
 928                data->acregmin          = NFS_DEF_ACREGMIN;
 929                data->acregmax          = NFS_DEF_ACREGMAX;
 930                data->acdirmin          = NFS_DEF_ACDIRMIN;
 931                data->acdirmax          = NFS_DEF_ACDIRMAX;
 932                data->mount_server.port = NFS_UNSPEC_PORT;
 933                data->nfs_server.port   = NFS_UNSPEC_PORT;
 934                data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 935                data->selected_flavor   = RPC_AUTH_MAXFLAVOR;
 936                data->minorversion      = 0;
 937                data->need_mount        = true;
 938                data->net               = current->nsproxy->net_ns;
 939                security_init_mnt_opts(&data->lsm_opts);
 940        }
 941        return data;
 942}
 943
 944static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 945{
 946        if (data) {
 947                kfree(data->client_address);
 948                kfree(data->mount_server.hostname);
 949                kfree(data->nfs_server.export_path);
 950                kfree(data->nfs_server.hostname);
 951                kfree(data->fscache_uniq);
 952                security_free_mnt_opts(&data->lsm_opts);
 953                kfree(data);
 954        }
 955}
 956
 957/*
 958 * Sanity-check a server address provided by the mount command.
 959 *
 960 * Address family must be initialized, and address must not be
 961 * the ANY address for that family.
 962 */
 963static int nfs_verify_server_address(struct sockaddr *addr)
 964{
 965        switch (addr->sa_family) {
 966        case AF_INET: {
 967                struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 968                return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 969        }
 970        case AF_INET6: {
 971                struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 972                return !ipv6_addr_any(sa);
 973        }
 974        }
 975
 976        dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
 977        return 0;
 978}
 979
 980/*
 981 * Select between a default port value and a user-specified port value.
 982 * If a zero value is set, then autobind will be used.
 983 */
 984static void nfs_set_port(struct sockaddr *sap, int *port,
 985                                 const unsigned short default_port)
 986{
 987        if (*port == NFS_UNSPEC_PORT)
 988                *port = default_port;
 989
 990        rpc_set_port(sap, *port);
 991}
 992
 993/*
 994 * Sanity check the NFS transport protocol.
 995 *
 996 */
 997static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
 998{
 999        switch (mnt->nfs_server.protocol) {
1000        case XPRT_TRANSPORT_UDP:
1001        case XPRT_TRANSPORT_TCP:
1002        case XPRT_TRANSPORT_RDMA:
1003                break;
1004        default:
1005                mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1006        }
1007}
1008
1009/*
1010 * For text based NFSv2/v3 mounts, the mount protocol transport default
1011 * settings should depend upon the specified NFS transport.
1012 */
1013static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1014{
1015        nfs_validate_transport_protocol(mnt);
1016
1017        if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1018            mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1019                        return;
1020        switch (mnt->nfs_server.protocol) {
1021        case XPRT_TRANSPORT_UDP:
1022                mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1023                break;
1024        case XPRT_TRANSPORT_TCP:
1025        case XPRT_TRANSPORT_RDMA:
1026                mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1027        }
1028}
1029
1030/*
1031 * Add 'flavor' to 'auth_info' if not already present.
1032 * Returns true if 'flavor' ends up in the list, false otherwise
1033 */
1034static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
1035                              rpc_authflavor_t flavor)
1036{
1037        unsigned int i;
1038        unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
1039
1040        /* make sure this flavor isn't already in the list */
1041        for (i = 0; i < auth_info->flavor_len; i++) {
1042                if (flavor == auth_info->flavors[i])
1043                        return true;
1044        }
1045
1046        if (auth_info->flavor_len + 1 >= max_flavor_len) {
1047                dfprintk(MOUNT, "NFS: too many sec= flavors\n");
1048                return false;
1049        }
1050
1051        auth_info->flavors[auth_info->flavor_len++] = flavor;
1052        return true;
1053}
1054
1055/*
1056 * Return true if 'match' is in auth_info or auth_info is empty.
1057 * Return false otherwise.
1058 */
1059bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
1060                         rpc_authflavor_t match)
1061{
1062        int i;
1063
1064        if (!auth_info->flavor_len)
1065                return true;
1066
1067        for (i = 0; i < auth_info->flavor_len; i++) {
1068                if (auth_info->flavors[i] == match)
1069                        return true;
1070        }
1071        return false;
1072}
1073EXPORT_SYMBOL_GPL(nfs_auth_info_match);
1074
1075/*
1076 * Parse the value of the 'sec=' option.
1077 */
1078static int nfs_parse_security_flavors(char *value,
1079                                      struct nfs_parsed_mount_data *mnt)
1080{
1081        substring_t args[MAX_OPT_ARGS];
1082        rpc_authflavor_t pseudoflavor;
1083        char *p;
1084
1085        dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1086
1087        while ((p = strsep(&value, ":")) != NULL) {
1088                switch (match_token(p, nfs_secflavor_tokens, args)) {
1089                case Opt_sec_none:
1090                        pseudoflavor = RPC_AUTH_NULL;
1091                        break;
1092                case Opt_sec_sys:
1093                        pseudoflavor = RPC_AUTH_UNIX;
1094                        break;
1095                case Opt_sec_krb5:
1096                        pseudoflavor = RPC_AUTH_GSS_KRB5;
1097                        break;
1098                case Opt_sec_krb5i:
1099                        pseudoflavor = RPC_AUTH_GSS_KRB5I;
1100                        break;
1101                case Opt_sec_krb5p:
1102                        pseudoflavor = RPC_AUTH_GSS_KRB5P;
1103                        break;
1104                case Opt_sec_lkey:
1105                        pseudoflavor = RPC_AUTH_GSS_LKEY;
1106                        break;
1107                case Opt_sec_lkeyi:
1108                        pseudoflavor = RPC_AUTH_GSS_LKEYI;
1109                        break;
1110                case Opt_sec_lkeyp:
1111                        pseudoflavor = RPC_AUTH_GSS_LKEYP;
1112                        break;
1113                case Opt_sec_spkm:
1114                        pseudoflavor = RPC_AUTH_GSS_SPKM;
1115                        break;
1116                case Opt_sec_spkmi:
1117                        pseudoflavor = RPC_AUTH_GSS_SPKMI;
1118                        break;
1119                case Opt_sec_spkmp:
1120                        pseudoflavor = RPC_AUTH_GSS_SPKMP;
1121                        break;
1122                default:
1123                        dfprintk(MOUNT,
1124                                 "NFS: sec= option '%s' not recognized\n", p);
1125                        return 0;
1126                }
1127
1128                if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
1129                        return 0;
1130        }
1131
1132        return 1;
1133}
1134
1135static int nfs_parse_version_string(char *string,
1136                struct nfs_parsed_mount_data *mnt,
1137                substring_t *args)
1138{
1139        mnt->flags &= ~NFS_MOUNT_VER3;
1140        switch (match_token(string, nfs_vers_tokens, args)) {
1141        case Opt_vers_2:
1142                mnt->version = 2;
1143                break;
1144        case Opt_vers_3:
1145                mnt->flags |= NFS_MOUNT_VER3;
1146                mnt->version = 3;
1147                break;
1148        case Opt_vers_4:
1149                /* Backward compatibility option. In future,
1150                 * the mount program should always supply
1151                 * a NFSv4 minor version number.
1152                 */
1153                mnt->version = 4;
1154                break;
1155        case Opt_vers_4_0:
1156                mnt->version = 4;
1157                mnt->minorversion = 0;
1158                break;
1159        case Opt_vers_4_1:
1160                mnt->version = 4;
1161                mnt->minorversion = 1;
1162                break;
1163        case Opt_vers_4_2:
1164                mnt->version = 4;
1165                mnt->minorversion = 2;
1166                break;
1167        default:
1168                return 0;
1169        }
1170        return 1;
1171}
1172
1173static int nfs_get_option_str(substring_t args[], char **option)
1174{
1175        kfree(*option);
1176        *option = match_strdup(args);
1177        return !*option;
1178}
1179
1180static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1181{
1182        int rc;
1183        char *string;
1184
1185        string = match_strdup(args);
1186        if (string == NULL)
1187                return -ENOMEM;
1188        rc = kstrtoul(string, 10, option);
1189        kfree(string);
1190
1191        return rc;
1192}
1193
1194static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
1195                unsigned long l_bound, unsigned long u_bound)
1196{
1197        int ret;
1198
1199        ret = nfs_get_option_ul(args, option);
1200        if (ret != 0)
1201                return ret;
1202        if (*option < l_bound || *option > u_bound)
1203                return -ERANGE;
1204        return 0;
1205}
1206
1207/*
1208 * Error-check and convert a string of mount options from user space into
1209 * a data structure.  The whole mount string is processed; bad options are
1210 * skipped as they are encountered.  If there were no errors, return 1;
1211 * otherwise return 0 (zero).
1212 */
1213static int nfs_parse_mount_options(char *raw,
1214                                   struct nfs_parsed_mount_data *mnt)
1215{
1216        char *p, *string, *secdata;
1217        int rc, sloppy = 0, invalid_option = 0;
1218        unsigned short protofamily = AF_UNSPEC;
1219        unsigned short mountfamily = AF_UNSPEC;
1220
1221        if (!raw) {
1222                dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1223                return 1;
1224        }
1225        dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1226
1227        secdata = alloc_secdata();
1228        if (!secdata)
1229                goto out_nomem;
1230
1231        rc = security_sb_copy_data(raw, secdata);
1232        if (rc)
1233                goto out_security_failure;
1234
1235        rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1236        if (rc)
1237                goto out_security_failure;
1238
1239        free_secdata(secdata);
1240
1241        while ((p = strsep(&raw, ",")) != NULL) {
1242                substring_t args[MAX_OPT_ARGS];
1243                unsigned long option;
1244                int token;
1245
1246                if (!*p)
1247                        continue;
1248
1249                dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1250
1251                token = match_token(p, nfs_mount_option_tokens, args);
1252                switch (token) {
1253
1254                /*
1255                 * boolean options:  foo/nofoo
1256                 */
1257                case Opt_soft:
1258                        mnt->flags |= NFS_MOUNT_SOFT;
1259                        break;
1260                case Opt_hard:
1261                        mnt->flags &= ~NFS_MOUNT_SOFT;
1262                        break;
1263                case Opt_posix:
1264                        mnt->flags |= NFS_MOUNT_POSIX;
1265                        break;
1266                case Opt_noposix:
1267                        mnt->flags &= ~NFS_MOUNT_POSIX;
1268                        break;
1269                case Opt_cto:
1270                        mnt->flags &= ~NFS_MOUNT_NOCTO;
1271                        break;
1272                case Opt_nocto:
1273                        mnt->flags |= NFS_MOUNT_NOCTO;
1274                        break;
1275                case Opt_ac:
1276                        mnt->flags &= ~NFS_MOUNT_NOAC;
1277                        break;
1278                case Opt_noac:
1279                        mnt->flags |= NFS_MOUNT_NOAC;
1280                        break;
1281                case Opt_lock:
1282                        mnt->flags &= ~NFS_MOUNT_NONLM;
1283                        mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1284                                        NFS_MOUNT_LOCAL_FCNTL);
1285                        break;
1286                case Opt_nolock:
1287                        mnt->flags |= NFS_MOUNT_NONLM;
1288                        mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1289                                       NFS_MOUNT_LOCAL_FCNTL);
1290                        break;
1291                case Opt_udp:
1292                        mnt->flags &= ~NFS_MOUNT_TCP;
1293                        mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1294                        break;
1295                case Opt_tcp:
1296                        mnt->flags |= NFS_MOUNT_TCP;
1297                        mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1298                        break;
1299                case Opt_rdma:
1300                        mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1301                        mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1302                        xprt_load_transport(p);
1303                        break;
1304                case Opt_acl:
1305                        mnt->flags &= ~NFS_MOUNT_NOACL;
1306                        break;
1307                case Opt_noacl:
1308                        mnt->flags |= NFS_MOUNT_NOACL;
1309                        break;
1310                case Opt_rdirplus:
1311                        mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1312                        break;
1313                case Opt_nordirplus:
1314                        mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1315                        break;
1316                case Opt_sharecache:
1317                        mnt->flags &= ~NFS_MOUNT_UNSHARED;
1318                        break;
1319                case Opt_nosharecache:
1320                        mnt->flags |= NFS_MOUNT_UNSHARED;
1321                        break;
1322                case Opt_resvport:
1323                        mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1324                        break;
1325                case Opt_noresvport:
1326                        mnt->flags |= NFS_MOUNT_NORESVPORT;
1327                        break;
1328                case Opt_fscache:
1329                        mnt->options |= NFS_OPTION_FSCACHE;
1330                        kfree(mnt->fscache_uniq);
1331                        mnt->fscache_uniq = NULL;
1332                        break;
1333                case Opt_nofscache:
1334                        mnt->options &= ~NFS_OPTION_FSCACHE;
1335                        kfree(mnt->fscache_uniq);
1336                        mnt->fscache_uniq = NULL;
1337                        break;
1338                case Opt_migration:
1339                        mnt->options |= NFS_OPTION_MIGRATION;
1340                        break;
1341                case Opt_nomigration:
1342                        mnt->options &= NFS_OPTION_MIGRATION;
1343                        break;
1344
1345                /*
1346                 * options that take numeric values
1347                 */
1348                case Opt_port:
1349                        if (nfs_get_option_ul(args, &option) ||
1350                            option > USHRT_MAX)
1351                                goto out_invalid_value;
1352                        mnt->nfs_server.port = option;
1353                        break;
1354                case Opt_rsize:
1355                        if (nfs_get_option_ul(args, &option))
1356                                goto out_invalid_value;
1357                        mnt->rsize = option;
1358                        break;
1359                case Opt_wsize:
1360                        if (nfs_get_option_ul(args, &option))
1361                                goto out_invalid_value;
1362                        mnt->wsize = option;
1363                        break;
1364                case Opt_bsize:
1365                        if (nfs_get_option_ul(args, &option))
1366                                goto out_invalid_value;
1367                        mnt->bsize = option;
1368                        break;
1369                case Opt_timeo:
1370                        if (nfs_get_option_ul_bound(args, &option, 1, INT_MAX))
1371                                goto out_invalid_value;
1372                        mnt->timeo = option;
1373                        break;
1374                case Opt_retrans:
1375                        if (nfs_get_option_ul_bound(args, &option, 0, INT_MAX))
1376                                goto out_invalid_value;
1377                        mnt->retrans = option;
1378                        break;
1379                case Opt_acregmin:
1380                        if (nfs_get_option_ul(args, &option))
1381                                goto out_invalid_value;
1382                        mnt->acregmin = option;
1383                        break;
1384                case Opt_acregmax:
1385                        if (nfs_get_option_ul(args, &option))
1386                                goto out_invalid_value;
1387                        mnt->acregmax = option;
1388                        break;
1389                case Opt_acdirmin:
1390                        if (nfs_get_option_ul(args, &option))
1391                                goto out_invalid_value;
1392                        mnt->acdirmin = option;
1393                        break;
1394                case Opt_acdirmax:
1395                        if (nfs_get_option_ul(args, &option))
1396                                goto out_invalid_value;
1397                        mnt->acdirmax = option;
1398                        break;
1399                case Opt_actimeo:
1400                        if (nfs_get_option_ul(args, &option))
1401                                goto out_invalid_value;
1402                        mnt->acregmin = mnt->acregmax =
1403                        mnt->acdirmin = mnt->acdirmax = option;
1404                        break;
1405                case Opt_namelen:
1406                        if (nfs_get_option_ul(args, &option))
1407                                goto out_invalid_value;
1408                        mnt->namlen = option;
1409                        break;
1410                case Opt_mountport:
1411                        if (nfs_get_option_ul(args, &option) ||
1412                            option > USHRT_MAX)
1413                                goto out_invalid_value;
1414                        mnt->mount_server.port = option;
1415                        break;
1416                case Opt_mountvers:
1417                        if (nfs_get_option_ul(args, &option) ||
1418                            option < NFS_MNT_VERSION ||
1419                            option > NFS_MNT3_VERSION)
1420                                goto out_invalid_value;
1421                        mnt->mount_server.version = option;
1422                        break;
1423                case Opt_minorversion:
1424                        if (nfs_get_option_ul(args, &option))
1425                                goto out_invalid_value;
1426                        if (option > NFS4_MAX_MINOR_VERSION)
1427                                goto out_invalid_value;
1428                        mnt->minorversion = option;
1429                        break;
1430
1431                /*
1432                 * options that take text values
1433                 */
1434                case Opt_nfsvers:
1435                        string = match_strdup(args);
1436                        if (string == NULL)
1437                                goto out_nomem;
1438                        rc = nfs_parse_version_string(string, mnt, args);
1439                        kfree(string);
1440                        if (!rc)
1441                                goto out_invalid_value;
1442                        break;
1443                case Opt_sec:
1444                        string = match_strdup(args);
1445                        if (string == NULL)
1446                                goto out_nomem;
1447                        rc = nfs_parse_security_flavors(string, mnt);
1448                        kfree(string);
1449                        if (!rc) {
1450                                dfprintk(MOUNT, "NFS:   unrecognized "
1451                                                "security flavor\n");
1452                                return 0;
1453                        }
1454                        break;
1455                case Opt_proto:
1456                        string = match_strdup(args);
1457                        if (string == NULL)
1458                                goto out_nomem;
1459                        token = match_token(string,
1460                                            nfs_xprt_protocol_tokens, args);
1461
1462                        protofamily = AF_INET;
1463                        switch (token) {
1464                        case Opt_xprt_udp6:
1465                                protofamily = AF_INET6;
1466                        case Opt_xprt_udp:
1467                                mnt->flags &= ~NFS_MOUNT_TCP;
1468                                mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1469                                break;
1470                        case Opt_xprt_tcp6:
1471                                protofamily = AF_INET6;
1472                        case Opt_xprt_tcp:
1473                                mnt->flags |= NFS_MOUNT_TCP;
1474                                mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1475                                break;
1476                        case Opt_xprt_rdma6:
1477                                protofamily = AF_INET6;
1478                        case Opt_xprt_rdma:
1479                                /* vector side protocols to TCP */
1480                                mnt->flags |= NFS_MOUNT_TCP;
1481                                mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1482                                xprt_load_transport(string);
1483                                break;
1484                        default:
1485                                dfprintk(MOUNT, "NFS:   unrecognized "
1486                                                "transport protocol\n");
1487                                kfree(string);
1488                                return 0;
1489                        }
1490                        kfree(string);
1491                        break;
1492                case Opt_mountproto:
1493                        string = match_strdup(args);
1494                        if (string == NULL)
1495                                goto out_nomem;
1496                        token = match_token(string,
1497                                            nfs_xprt_protocol_tokens, args);
1498                        kfree(string);
1499
1500                        mountfamily = AF_INET;
1501                        switch (token) {
1502                        case Opt_xprt_udp6:
1503                                mountfamily = AF_INET6;
1504                        case Opt_xprt_udp:
1505                                mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1506                                break;
1507                        case Opt_xprt_tcp6:
1508                                mountfamily = AF_INET6;
1509                        case Opt_xprt_tcp:
1510                                mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1511                                break;
1512                        case Opt_xprt_rdma: /* not used for side protocols */
1513                        default:
1514                                dfprintk(MOUNT, "NFS:   unrecognized "
1515                                                "transport protocol\n");
1516                                return 0;
1517                        }
1518                        break;
1519                case Opt_addr:
1520                        string = match_strdup(args);
1521                        if (string == NULL)
1522                                goto out_nomem;
1523                        mnt->nfs_server.addrlen =
1524                                rpc_pton(mnt->net, string, strlen(string),
1525                                        (struct sockaddr *)
1526                                        &mnt->nfs_server.address,
1527                                        sizeof(mnt->nfs_server.address));
1528                        kfree(string);
1529                        if (mnt->nfs_server.addrlen == 0)
1530                                goto out_invalid_address;
1531                        break;
1532                case Opt_clientaddr:
1533                        if (nfs_get_option_str(args, &mnt->client_address))
1534                                goto out_nomem;
1535                        break;
1536                case Opt_mounthost:
1537                        if (nfs_get_option_str(args,
1538                                               &mnt->mount_server.hostname))
1539                                goto out_nomem;
1540                        break;
1541                case Opt_mountaddr:
1542                        string = match_strdup(args);
1543                        if (string == NULL)
1544                                goto out_nomem;
1545                        mnt->mount_server.addrlen =
1546                                rpc_pton(mnt->net, string, strlen(string),
1547                                        (struct sockaddr *)
1548                                        &mnt->mount_server.address,
1549                                        sizeof(mnt->mount_server.address));
1550                        kfree(string);
1551                        if (mnt->mount_server.addrlen == 0)
1552                                goto out_invalid_address;
1553                        break;
1554                case Opt_lookupcache:
1555                        string = match_strdup(args);
1556                        if (string == NULL)
1557                                goto out_nomem;
1558                        token = match_token(string,
1559                                        nfs_lookupcache_tokens, args);
1560                        kfree(string);
1561                        switch (token) {
1562                                case Opt_lookupcache_all:
1563                                        mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1564                                        break;
1565                                case Opt_lookupcache_positive:
1566                                        mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1567                                        mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1568                                        break;
1569                                case Opt_lookupcache_none:
1570                                        mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1571                                        break;
1572                                default:
1573                                        dfprintk(MOUNT, "NFS:   invalid "
1574                                                        "lookupcache argument\n");
1575                                        return 0;
1576                        };
1577                        break;
1578                case Opt_fscache_uniq:
1579                        if (nfs_get_option_str(args, &mnt->fscache_uniq))
1580                                goto out_nomem;
1581                        mnt->options |= NFS_OPTION_FSCACHE;
1582                        break;
1583                case Opt_local_lock:
1584                        string = match_strdup(args);
1585                        if (string == NULL)
1586                                goto out_nomem;
1587                        token = match_token(string, nfs_local_lock_tokens,
1588                                        args);
1589                        kfree(string);
1590                        switch (token) {
1591                        case Opt_local_lock_all:
1592                                mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1593                                               NFS_MOUNT_LOCAL_FCNTL);
1594                                break;
1595                        case Opt_local_lock_flock:
1596                                mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1597                                break;
1598                        case Opt_local_lock_posix:
1599                                mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1600                                break;
1601                        case Opt_local_lock_none:
1602                                mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1603                                                NFS_MOUNT_LOCAL_FCNTL);
1604                                break;
1605                        default:
1606                                dfprintk(MOUNT, "NFS:   invalid "
1607                                                "local_lock argument\n");
1608                                return 0;
1609                        };
1610                        break;
1611
1612                /*
1613                 * Special options
1614                 */
1615                case Opt_sloppy:
1616                        sloppy = 1;
1617                        dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1618                        break;
1619                case Opt_userspace:
1620                case Opt_deprecated:
1621                        dfprintk(MOUNT, "NFS:   ignoring mount option "
1622                                        "'%s'\n", p);
1623                        break;
1624
1625                default:
1626                        invalid_option = 1;
1627                        dfprintk(MOUNT, "NFS:   unrecognized mount option "
1628                                        "'%s'\n", p);
1629                }
1630        }
1631
1632        if (!sloppy && invalid_option)
1633                return 0;
1634
1635        if (mnt->minorversion && mnt->version != 4)
1636                goto out_minorversion_mismatch;
1637
1638        if (mnt->options & NFS_OPTION_MIGRATION &&
1639            (mnt->version != 4 || mnt->minorversion != 0))
1640                goto out_migration_misuse;
1641
1642        /*
1643         * verify that any proto=/mountproto= options match the address
1644         * families in the addr=/mountaddr= options.
1645         */
1646        if (protofamily != AF_UNSPEC &&
1647            protofamily != mnt->nfs_server.address.ss_family)
1648                goto out_proto_mismatch;
1649
1650        if (mountfamily != AF_UNSPEC) {
1651                if (mnt->mount_server.addrlen) {
1652                        if (mountfamily != mnt->mount_server.address.ss_family)
1653                                goto out_mountproto_mismatch;
1654                } else {
1655                        if (mountfamily != mnt->nfs_server.address.ss_family)
1656                                goto out_mountproto_mismatch;
1657                }
1658        }
1659
1660        return 1;
1661
1662out_mountproto_mismatch:
1663        printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1664                         "option\n");
1665        return 0;
1666out_proto_mismatch:
1667        printk(KERN_INFO "NFS: server address does not match proto= option\n");
1668        return 0;
1669out_invalid_address:
1670        printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1671        return 0;
1672out_invalid_value:
1673        printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1674        return 0;
1675out_minorversion_mismatch:
1676        printk(KERN_INFO "NFS: mount option vers=%u does not support "
1677                         "minorversion=%u\n", mnt->version, mnt->minorversion);
1678        return 0;
1679out_migration_misuse:
1680        printk(KERN_INFO
1681                "NFS: 'migration' not supported for this NFS version\n");
1682        return 0;
1683out_nomem:
1684        printk(KERN_INFO "NFS: not enough memory to parse option\n");
1685        return 0;
1686out_security_failure:
1687        free_secdata(secdata);
1688        printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1689        return 0;
1690}
1691
1692/*
1693 * Ensure that a specified authtype in args->auth_info is supported by
1694 * the server. Returns 0 and sets args->selected_flavor if it's ok, and
1695 * -EACCES if not.
1696 */
1697static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
1698                        rpc_authflavor_t *server_authlist, unsigned int count)
1699{
1700        rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
1701        unsigned int i;
1702        int use_auth_null = false;
1703
1704        /*
1705         * If the sec= mount option is used, the specified flavor or AUTH_NULL
1706         * must be in the list returned by the server.
1707         *
1708         * AUTH_NULL has a special meaning when it's in the server list - it
1709         * means that the server will ignore the rpc creds, so any flavor
1710         * can be used but still use the sec= that was specified.
1711         */
1712        for (i = 0; i < count; i++) {
1713                flavor = server_authlist[i];
1714
1715                if (nfs_auth_info_match(&args->auth_info, flavor))
1716                        goto out;
1717
1718                if (flavor == RPC_AUTH_NULL)
1719                        use_auth_null = true;
1720        }
1721
1722        if (use_auth_null) {
1723                flavor = RPC_AUTH_NULL;
1724                goto out;
1725        }
1726
1727        dfprintk(MOUNT,
1728                 "NFS: specified auth flavors not supported by server\n");
1729        return -EACCES;
1730
1731out:
1732        args->selected_flavor = flavor;
1733        dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
1734        return 0;
1735}
1736
1737/*
1738 * Use the remote server's MOUNT service to request the NFS file handle
1739 * corresponding to the provided path.
1740 */
1741static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1742                             struct nfs_fh *root_fh,
1743                             rpc_authflavor_t *server_authlist,
1744                             unsigned int *server_authlist_len)
1745{
1746        struct nfs_mount_request request = {
1747                .sap            = (struct sockaddr *)
1748                                                &args->mount_server.address,
1749                .dirpath        = args->nfs_server.export_path,
1750                .protocol       = args->mount_server.protocol,
1751                .fh             = root_fh,
1752                .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1753                .auth_flav_len  = server_authlist_len,
1754                .auth_flavs     = server_authlist,
1755                .net            = args->net,
1756        };
1757        int status;
1758
1759        if (args->mount_server.version == 0) {
1760                switch (args->version) {
1761                        default:
1762                                args->mount_server.version = NFS_MNT3_VERSION;
1763                                break;
1764                        case 2:
1765                                args->mount_server.version = NFS_MNT_VERSION;
1766                }
1767        }
1768        request.version = args->mount_server.version;
1769
1770        if (args->mount_server.hostname)
1771                request.hostname = args->mount_server.hostname;
1772        else
1773                request.hostname = args->nfs_server.hostname;
1774
1775        /*
1776         * Construct the mount server's address.
1777         */
1778        if (args->mount_server.address.ss_family == AF_UNSPEC) {
1779                memcpy(request.sap, &args->nfs_server.address,
1780                       args->nfs_server.addrlen);
1781                args->mount_server.addrlen = args->nfs_server.addrlen;
1782        }
1783        request.salen = args->mount_server.addrlen;
1784        nfs_set_port(request.sap, &args->mount_server.port, 0);
1785
1786        /*
1787         * Now ask the mount server to map our export path
1788         * to a file handle.
1789         */
1790        status = nfs_mount(&request);
1791        if (status != 0) {
1792                dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1793                                request.hostname, status);
1794                return status;
1795        }
1796
1797        return 0;
1798}
1799
1800static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1801                                        struct nfs_subversion *nfs_mod)
1802{
1803        int status;
1804        unsigned int i;
1805        bool tried_auth_unix = false;
1806        bool auth_null_in_list = false;
1807        struct nfs_server *server = ERR_PTR(-EACCES);
1808        struct nfs_parsed_mount_data *args = mount_info->parsed;
1809        rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1810        unsigned int authlist_len = ARRAY_SIZE(authlist);
1811
1812        status = nfs_request_mount(args, mount_info->mntfh, authlist,
1813                                        &authlist_len);
1814        if (status)
1815                return ERR_PTR(status);
1816
1817        /*
1818         * Was a sec= authflavor specified in the options? First, verify
1819         * whether the server supports it, and then just try to use it if so.
1820         */
1821        if (args->auth_info.flavor_len > 0) {
1822                status = nfs_verify_authflavors(args, authlist, authlist_len);
1823                dfprintk(MOUNT, "NFS: using auth flavor %u\n",
1824                         args->selected_flavor);
1825                if (status)
1826                        return ERR_PTR(status);
1827                return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1828        }
1829
1830        /*
1831         * No sec= option was provided. RFC 2623, section 2.7 suggests we
1832         * SHOULD prefer the flavor listed first. However, some servers list
1833         * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1834         */
1835        for (i = 0; i < authlist_len; ++i) {
1836                rpc_authflavor_t flavor;
1837                struct rpcsec_gss_info info;
1838
1839                flavor = authlist[i];
1840                switch (flavor) {
1841                case RPC_AUTH_UNIX:
1842                        tried_auth_unix = true;
1843                        break;
1844                case RPC_AUTH_NULL:
1845                        auth_null_in_list = true;
1846                        continue;
1847                default:
1848                        if (rpcauth_get_gssinfo(flavor, &info) != 0)
1849                                continue;
1850                        /* Fallthrough */
1851                }
1852                dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1853                args->selected_flavor = flavor;
1854                server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1855                if (!IS_ERR(server))
1856                        return server;
1857        }
1858
1859        /*
1860         * Nothing we tried so far worked. At this point, give up if we've
1861         * already tried AUTH_UNIX or if the server's list doesn't contain
1862         * AUTH_NULL
1863         */
1864        if (tried_auth_unix || !auth_null_in_list)
1865                return server;
1866
1867        /* Last chance! Try AUTH_UNIX */
1868        dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1869        args->selected_flavor = RPC_AUTH_UNIX;
1870        return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1871}
1872
1873struct dentry *nfs_try_mount(int flags, const char *dev_name,
1874                             struct nfs_mount_info *mount_info,
1875                             struct nfs_subversion *nfs_mod)
1876{
1877        struct nfs_server *server;
1878
1879        if (mount_info->parsed->need_mount)
1880                server = nfs_try_mount_request(mount_info, nfs_mod);
1881        else
1882                server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1883
1884        if (IS_ERR(server))
1885                return ERR_CAST(server);
1886
1887        return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1888}
1889EXPORT_SYMBOL_GPL(nfs_try_mount);
1890
1891/*
1892 * Split "dev_name" into "hostname:export_path".
1893 *
1894 * The leftmost colon demarks the split between the server's hostname
1895 * and the export path.  If the hostname starts with a left square
1896 * bracket, then it may contain colons.
1897 *
1898 * Note: caller frees hostname and export path, even on error.
1899 */
1900static int nfs_parse_devname(const char *dev_name,
1901                             char **hostname, size_t maxnamlen,
1902                             char **export_path, size_t maxpathlen)
1903{
1904        size_t len;
1905        char *end;
1906
1907        /* Is the host name protected with square brakcets? */
1908        if (*dev_name == '[') {
1909                end = strchr(++dev_name, ']');
1910                if (end == NULL || end[1] != ':')
1911                        goto out_bad_devname;
1912
1913                len = end - dev_name;
1914                end++;
1915        } else {
1916                char *comma;
1917
1918                end = strchr(dev_name, ':');
1919                if (end == NULL)
1920                        goto out_bad_devname;
1921                len = end - dev_name;
1922
1923                /* kill possible hostname list: not supported */
1924                comma = strchr(dev_name, ',');
1925                if (comma != NULL && comma < end)
1926                        *comma = 0;
1927        }
1928
1929        if (len > maxnamlen)
1930                goto out_hostname;
1931
1932        /* N.B. caller will free nfs_server.hostname in all cases */
1933        *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1934        if (*hostname == NULL)
1935                goto out_nomem;
1936        len = strlen(++end);
1937        if (len > maxpathlen)
1938                goto out_path;
1939        *export_path = kstrndup(end, len, GFP_KERNEL);
1940        if (!*export_path)
1941                goto out_nomem;
1942
1943        dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1944        return 0;
1945
1946out_bad_devname:
1947        dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1948        return -EINVAL;
1949
1950out_nomem:
1951        dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1952        return -ENOMEM;
1953
1954out_hostname:
1955        dfprintk(MOUNT, "NFS: server hostname too long\n");
1956        return -ENAMETOOLONG;
1957
1958out_path:
1959        dfprintk(MOUNT, "NFS: export pathname too long\n");
1960        return -ENAMETOOLONG;
1961}
1962
1963/*
1964 * Validate the NFS2/NFS3 mount data
1965 * - fills in the mount root filehandle
1966 *
1967 * For option strings, user space handles the following behaviors:
1968 *
1969 * + DNS: mapping server host name to IP address ("addr=" option)
1970 *
1971 * + failure mode: how to behave if a mount request can't be handled
1972 *   immediately ("fg/bg" option)
1973 *
1974 * + retry: how often to retry a mount request ("retry=" option)
1975 *
1976 * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1977 *   mountproto=tcp after mountproto=udp, and so on
1978 */
1979static int nfs23_validate_mount_data(void *options,
1980                                     struct nfs_parsed_mount_data *args,
1981                                     struct nfs_fh *mntfh,
1982                                     const char *dev_name)
1983{
1984        struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1985        struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1986        int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1987
1988        if (data == NULL)
1989                goto out_no_data;
1990
1991        args->version = NFS_DEFAULT_VERSION;
1992        switch (data->version) {
1993        case 1:
1994                data->namlen = 0;
1995        case 2:
1996                data->bsize = 0;
1997        case 3:
1998                if (data->flags & NFS_MOUNT_VER3)
1999                        goto out_no_v3;
2000                data->root.size = NFS2_FHSIZE;
2001                memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
2002                /* Turn off security negotiation */
2003                extra_flags |= NFS_MOUNT_SECFLAVOUR;
2004        case 4:
2005                if (data->flags & NFS_MOUNT_SECFLAVOUR)
2006                        goto out_no_sec;
2007        case 5:
2008                memset(data->context, 0, sizeof(data->context));
2009        case 6:
2010                if (data->flags & NFS_MOUNT_VER3) {
2011                        if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
2012                                goto out_invalid_fh;
2013                        mntfh->size = data->root.size;
2014                        args->version = 3;
2015                } else {
2016                        mntfh->size = NFS2_FHSIZE;
2017                        args->version = 2;
2018                }
2019
2020
2021                memcpy(mntfh->data, data->root.data, mntfh->size);
2022                if (mntfh->size < sizeof(mntfh->data))
2023                        memset(mntfh->data + mntfh->size, 0,
2024                               sizeof(mntfh->data) - mntfh->size);
2025
2026                /*
2027                 * Translate to nfs_parsed_mount_data, which nfs_fill_super
2028                 * can deal with.
2029                 */
2030                args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
2031                args->flags             |= extra_flags;
2032                args->rsize             = data->rsize;
2033                args->wsize             = data->wsize;
2034                args->timeo             = data->timeo;
2035                args->retrans           = data->retrans;
2036                args->acregmin          = data->acregmin;
2037                args->acregmax          = data->acregmax;
2038                args->acdirmin          = data->acdirmin;
2039                args->acdirmax          = data->acdirmax;
2040                args->need_mount        = false;
2041
2042                memcpy(sap, &data->addr, sizeof(data->addr));
2043                args->nfs_server.addrlen = sizeof(data->addr);
2044                args->nfs_server.port = ntohs(data->addr.sin_port);
2045                if (!nfs_verify_server_address(sap))
2046                        goto out_no_address;
2047
2048                if (!(data->flags & NFS_MOUNT_TCP))
2049                        args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
2050                /* N.B. caller will free nfs_server.hostname in all cases */
2051                args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
2052                args->namlen            = data->namlen;
2053                args->bsize             = data->bsize;
2054
2055                if (data->flags & NFS_MOUNT_SECFLAVOUR)
2056                        args->selected_flavor = data->pseudoflavor;
2057                else
2058                        args->selected_flavor = RPC_AUTH_UNIX;
2059                if (!args->nfs_server.hostname)
2060                        goto out_nomem;
2061
2062                if (!(data->flags & NFS_MOUNT_NONLM))
2063                        args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
2064                                         NFS_MOUNT_LOCAL_FCNTL);
2065                else
2066                        args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
2067                                        NFS_MOUNT_LOCAL_FCNTL);
2068                /*
2069                 * The legacy version 6 binary mount data from userspace has a
2070                 * field used only to transport selinux information into the
2071                 * the kernel.  To continue to support that functionality we
2072                 * have a touch of selinux knowledge here in the NFS code. The
2073                 * userspace code converted context=blah to just blah so we are
2074                 * converting back to the full string selinux understands.
2075                 */
2076                if (data->context[0]){
2077#ifdef CONFIG_SECURITY_SELINUX
2078                        int rc;
2079                        char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
2080                        if (!opts_str)
2081                                return -ENOMEM;
2082                        strcpy(opts_str, "context=");
2083                        data->context[NFS_MAX_CONTEXT_LEN] = '\0';
2084                        strcat(opts_str, &data->context[0]);
2085                        rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
2086                        kfree(opts_str);
2087                        if (rc)
2088                                return rc;
2089#else
2090                        return -EINVAL;
2091#endif
2092                }
2093
2094                break;
2095        default:
2096                return NFS_TEXT_DATA;
2097        }
2098
2099        return 0;
2100
2101out_no_data:
2102        dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2103        return -EINVAL;
2104
2105out_no_v3:
2106        dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2107                 data->version);
2108        return -EINVAL;
2109
2110out_no_sec:
2111        dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2112        return -EINVAL;
2113
2114out_nomem:
2115        dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2116        return -ENOMEM;
2117
2118out_no_address:
2119        dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2120        return -EINVAL;
2121
2122out_invalid_fh:
2123        dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2124        return -EINVAL;
2125}
2126
2127#if IS_ENABLED(CONFIG_NFS_V4)
2128static int nfs_validate_mount_data(struct file_system_type *fs_type,
2129                                   void *options,
2130                                   struct nfs_parsed_mount_data *args,
2131                                   struct nfs_fh *mntfh,
2132                                   const char *dev_name)
2133{
2134        if (fs_type == &nfs_fs_type)
2135                return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2136        return nfs4_validate_mount_data(options, args, dev_name);
2137}
2138#else
2139static int nfs_validate_mount_data(struct file_system_type *fs_type,
2140                                   void *options,
2141                                   struct nfs_parsed_mount_data *args,
2142                                   struct nfs_fh *mntfh,
2143                                   const char *dev_name)
2144{
2145        return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2146}
2147#endif
2148
2149static int nfs_validate_text_mount_data(void *options,
2150                                        struct nfs_parsed_mount_data *args,
2151                                        const char *dev_name)
2152{
2153        int port = 0;
2154        int max_namelen = PAGE_SIZE;
2155        int max_pathlen = NFS_MAXPATHLEN;
2156        struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2157
2158        if (nfs_parse_mount_options((char *)options, args) == 0)
2159                return -EINVAL;
2160
2161        if (!nfs_verify_server_address(sap))
2162                goto out_no_address;
2163
2164        if (args->version == 4) {
2165#if IS_ENABLED(CONFIG_NFS_V4)
2166                port = NFS_PORT;
2167                max_namelen = NFS4_MAXNAMLEN;
2168                max_pathlen = NFS4_MAXPATHLEN;
2169                nfs_validate_transport_protocol(args);
2170                if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2171                        goto out_invalid_transport_udp;
2172                nfs4_validate_mount_flags(args);
2173#else
2174                goto out_v4_not_compiled;
2175#endif /* CONFIG_NFS_V4 */
2176        } else
2177                nfs_set_mount_transport_protocol(args);
2178
2179        nfs_set_port(sap, &args->nfs_server.port, port);
2180
2181        return nfs_parse_devname(dev_name,
2182                                   &args->nfs_server.hostname,
2183                                   max_namelen,
2184                                   &args->nfs_server.export_path,
2185                                   max_pathlen);
2186
2187#if !IS_ENABLED(CONFIG_NFS_V4)
2188out_v4_not_compiled:
2189        dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2190        return -EPROTONOSUPPORT;
2191#else
2192out_invalid_transport_udp:
2193        dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2194        return -EINVAL;
2195#endif /* !CONFIG_NFS_V4 */
2196
2197out_no_address:
2198        dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2199        return -EINVAL;
2200}
2201
2202#define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
2203                | NFS_MOUNT_SECURE \
2204                | NFS_MOUNT_TCP \
2205                | NFS_MOUNT_VER3 \
2206                | NFS_MOUNT_KERBEROS \
2207                | NFS_MOUNT_NONLM \
2208                | NFS_MOUNT_BROKEN_SUID \
2209                | NFS_MOUNT_STRICTLOCK \
2210                | NFS_MOUNT_LEGACY_INTERFACE)
2211
2212#define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
2213                ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
2214
2215static int
2216nfs_compare_remount_data(struct nfs_server *nfss,
2217                         struct nfs_parsed_mount_data *data)
2218{
2219        if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
2220            data->rsize != nfss->rsize ||
2221            data->wsize != nfss->wsize ||
2222            data->version != nfss->nfs_client->rpc_ops->version ||
2223            data->minorversion != nfss->nfs_client->cl_minorversion ||
2224            data->retrans != nfss->client->cl_timeout->to_retries ||
2225            !nfs_auth_info_match(&data->auth_info, nfss->client->cl_auth->au_flavor) ||
2226            data->acregmin != nfss->acregmin / HZ ||
2227            data->acregmax != nfss->acregmax / HZ ||
2228            data->acdirmin != nfss->acdirmin / HZ ||
2229            data->acdirmax != nfss->acdirmax / HZ ||
2230            data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2231            data->nfs_server.port != nfss->port ||
2232            data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2233            !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2234                          (struct sockaddr *)&nfss->nfs_client->cl_addr))
2235                return -EINVAL;
2236
2237        return 0;
2238}
2239
2240int
2241nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2242{
2243        int error;
2244        struct nfs_server *nfss = sb->s_fs_info;
2245        struct nfs_parsed_mount_data *data;
2246        struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2247        struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2248        u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2249
2250        sync_filesystem(sb);
2251
2252        /*
2253         * Userspace mount programs that send binary options generally send
2254         * them populated with default values. We have no way to know which
2255         * ones were explicitly specified. Fall back to legacy behavior and
2256         * just return success.
2257         */
2258        if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2259            (nfsvers <= 3 && (!options || (options->version >= 1 &&
2260                                           options->version <= 6))))
2261                return 0;
2262
2263        data = kzalloc(sizeof(*data), GFP_KERNEL);
2264        if (data == NULL)
2265                return -ENOMEM;
2266
2267        /* fill out struct with values from existing mount */
2268        data->flags = nfss->flags;
2269        data->rsize = nfss->rsize;
2270        data->wsize = nfss->wsize;
2271        data->retrans = nfss->client->cl_timeout->to_retries;
2272        data->selected_flavor = nfss->client->cl_auth->au_flavor;
2273        data->acregmin = nfss->acregmin / HZ;
2274        data->acregmax = nfss->acregmax / HZ;
2275        data->acdirmin = nfss->acdirmin / HZ;
2276        data->acdirmax = nfss->acdirmax / HZ;
2277        data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2278        data->nfs_server.port = nfss->port;
2279        data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2280        data->version = nfsvers;
2281        data->minorversion = nfss->nfs_client->cl_minorversion;
2282        data->net = current->nsproxy->net_ns;
2283        memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2284                data->nfs_server.addrlen);
2285
2286        /* overwrite those values with any that were specified */
2287        error = -EINVAL;
2288        if (!nfs_parse_mount_options((char *)options, data))
2289                goto out;
2290
2291        /*
2292         * noac is a special case. It implies -o sync, but that's not
2293         * necessarily reflected in the mtab options. do_remount_sb
2294         * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2295         * remount options, so we have to explicitly reset it.
2296         */
2297        if (data->flags & NFS_MOUNT_NOAC)
2298                *flags |= MS_SYNCHRONOUS;
2299
2300        /* compare new mount options with old ones */
2301        error = nfs_compare_remount_data(nfss, data);
2302out:
2303        kfree(data);
2304        return error;
2305}
2306EXPORT_SYMBOL_GPL(nfs_remount);
2307
2308/*
2309 * Initialise the common bits of the superblock
2310 */
2311inline void nfs_initialise_sb(struct super_block *sb)
2312{
2313        struct nfs_server *server = NFS_SB(sb);
2314
2315        sb->s_magic = NFS_SUPER_MAGIC;
2316
2317        /* We probably want something more informative here */
2318        snprintf(sb->s_id, sizeof(sb->s_id),
2319                 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2320
2321        if (sb->s_blocksize == 0)
2322                sb->s_blocksize = nfs_block_bits(server->wsize,
2323                                                 &sb->s_blocksize_bits);
2324
2325        sb->s_bdi = &server->backing_dev_info;
2326
2327        nfs_super_set_maxbytes(sb, server->maxfilesize);
2328}
2329
2330/*
2331 * Finish setting up an NFS2/3 superblock
2332 */
2333void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2334{
2335        struct nfs_parsed_mount_data *data = mount_info->parsed;
2336        struct nfs_server *server = NFS_SB(sb);
2337
2338        sb->s_blocksize_bits = 0;
2339        sb->s_blocksize = 0;
2340        sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2341        sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2342        if (data && data->bsize)
2343                sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
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                sb->s_time_gran = 1;
2351        }
2352
2353        nfs_initialise_sb(sb);
2354}
2355EXPORT_SYMBOL_GPL(nfs_fill_super);
2356
2357/*
2358 * Finish setting up a cloned NFS2/3/4 superblock
2359 */
2360void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2361{
2362        const struct super_block *old_sb = mount_info->cloned->sb;
2363        struct nfs_server *server = NFS_SB(sb);
2364
2365        sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2366        sb->s_blocksize = old_sb->s_blocksize;
2367        sb->s_maxbytes = old_sb->s_maxbytes;
2368        sb->s_xattr = old_sb->s_xattr;
2369        sb->s_op = old_sb->s_op;
2370        sb->s_time_gran = 1;
2371
2372        if (server->nfs_client->rpc_ops->version != 2) {
2373                /* The VFS shouldn't apply the umask to mode bits. We will do
2374                 * so ourselves when necessary.
2375                 */
2376                sb->s_flags |= MS_POSIXACL;
2377        }
2378
2379        nfs_initialise_sb(sb);
2380}
2381
2382static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2383{
2384        const struct nfs_server *a = s->s_fs_info;
2385        const struct rpc_clnt *clnt_a = a->client;
2386        const struct rpc_clnt *clnt_b = b->client;
2387
2388        if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2389                goto Ebusy;
2390        if (a->nfs_client != b->nfs_client)
2391                goto Ebusy;
2392        if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
2393                goto Ebusy;
2394        if (a->wsize != b->wsize)
2395                goto Ebusy;
2396        if (a->rsize != b->rsize)
2397                goto Ebusy;
2398        if (a->acregmin != b->acregmin)
2399                goto Ebusy;
2400        if (a->acregmax != b->acregmax)
2401                goto Ebusy;
2402        if (a->acdirmin != b->acdirmin)
2403                goto Ebusy;
2404        if (a->acdirmax != b->acdirmax)
2405                goto Ebusy;
2406        if (b->auth_info.flavor_len > 0 &&
2407           clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2408                goto Ebusy;
2409        return 1;
2410Ebusy:
2411        return 0;
2412}
2413
2414struct nfs_sb_mountdata {
2415        struct nfs_server *server;
2416        int mntflags;
2417};
2418
2419static int nfs_set_super(struct super_block *s, void *data)
2420{
2421        struct nfs_sb_mountdata *sb_mntdata = data;
2422        struct nfs_server *server = sb_mntdata->server;
2423        int ret;
2424
2425        s->s_flags = sb_mntdata->mntflags;
2426        s->s_fs_info = server;
2427        s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2428        ret = set_anon_super(s, server);
2429        if (ret == 0)
2430                server->s_dev = s->s_dev;
2431        return ret;
2432}
2433
2434static int nfs_compare_super_address(struct nfs_server *server1,
2435                                     struct nfs_server *server2)
2436{
2437        struct sockaddr *sap1, *sap2;
2438        struct rpc_xprt *xprt1 = server1->client->cl_xprt;
2439        struct rpc_xprt *xprt2 = server2->client->cl_xprt;
2440
2441        if (!net_eq(xprt1->xprt_net, xprt2->xprt_net))
2442                return 0;
2443
2444        sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2445        sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2446
2447        if (sap1->sa_family != sap2->sa_family)
2448                return 0;
2449
2450        switch (sap1->sa_family) {
2451        case AF_INET: {
2452                struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2453                struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2454                if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2455                        return 0;
2456                if (sin1->sin_port != sin2->sin_port)
2457                        return 0;
2458                break;
2459        }
2460        case AF_INET6: {
2461                struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2462                struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2463                if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2464                        return 0;
2465                if (sin1->sin6_port != sin2->sin6_port)
2466                        return 0;
2467                break;
2468        }
2469        default:
2470                return 0;
2471        }
2472
2473        return 1;
2474}
2475
2476static int nfs_compare_super(struct super_block *sb, void *data)
2477{
2478        struct nfs_sb_mountdata *sb_mntdata = data;
2479        struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2480        int mntflags = sb_mntdata->mntflags;
2481
2482        if (!nfs_compare_super_address(old, server))
2483                return 0;
2484        /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2485        if (old->flags & NFS_MOUNT_UNSHARED)
2486                return 0;
2487        if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2488                return 0;
2489        return nfs_compare_mount_options(sb, server, mntflags);
2490}
2491
2492#ifdef CONFIG_NFS_FSCACHE
2493static void nfs_get_cache_cookie(struct super_block *sb,
2494                                 struct nfs_parsed_mount_data *parsed,
2495                                 struct nfs_clone_mount *cloned)
2496{
2497        struct nfs_server *nfss = NFS_SB(sb);
2498        char *uniq = NULL;
2499        int ulen = 0;
2500
2501        nfss->fscache_key = NULL;
2502        nfss->fscache = NULL;
2503
2504        if (parsed) {
2505                if (!(parsed->options & NFS_OPTION_FSCACHE))
2506                        return;
2507                if (parsed->fscache_uniq) {
2508                        uniq = parsed->fscache_uniq;
2509                        ulen = strlen(parsed->fscache_uniq);
2510                }
2511        } else if (cloned) {
2512                struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2513                if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2514                        return;
2515                if (mnt_s->fscache_key) {
2516                        uniq = mnt_s->fscache_key->key.uniquifier;
2517                        ulen = mnt_s->fscache_key->key.uniq_len;
2518                };
2519        } else
2520                return;
2521
2522        nfs_fscache_get_super_cookie(sb, uniq, ulen);
2523}
2524#else
2525static void nfs_get_cache_cookie(struct super_block *sb,
2526                                 struct nfs_parsed_mount_data *parsed,
2527                                 struct nfs_clone_mount *cloned)
2528{
2529}
2530#endif
2531
2532static int nfs_bdi_register(struct nfs_server *server)
2533{
2534        return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2535}
2536
2537int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2538                        struct nfs_mount_info *mount_info)
2539{
2540        int error;
2541        unsigned long kflags = 0, kflags_out = 0;
2542        if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2543                kflags |= SECURITY_LSM_NATIVE_LABELS;
2544
2545        error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
2546                                                kflags, &kflags_out);
2547        if (error)
2548                goto err;
2549
2550        if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2551                !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2552                NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2553err:
2554        return error;
2555}
2556EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2557
2558int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2559                          struct nfs_mount_info *mount_info)
2560{
2561        /* clone any lsm security options from the parent to the new sb */
2562        if (d_inode(mntroot)->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2563                return -ESTALE;
2564        return security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2565}
2566EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2567
2568struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2569                                   int flags, const char *dev_name,
2570                                   struct nfs_mount_info *mount_info,
2571                                   struct nfs_subversion *nfs_mod)
2572{
2573        struct super_block *s;
2574        struct dentry *mntroot = ERR_PTR(-ENOMEM);
2575        int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2576        struct nfs_sb_mountdata sb_mntdata = {
2577                .mntflags = flags,
2578                .server = server,
2579        };
2580        int error;
2581
2582        if (server->flags & NFS_MOUNT_UNSHARED)
2583                compare_super = NULL;
2584
2585        /* -o noac implies -o sync */
2586        if (server->flags & NFS_MOUNT_NOAC)
2587                sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2588
2589        if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
2590                if (mount_info->cloned->sb->s_flags & MS_SYNCHRONOUS)
2591                        sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2592
2593        /* Get a superblock - note that we may end up sharing one that already exists */
2594        s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2595        if (IS_ERR(s)) {
2596                mntroot = ERR_CAST(s);
2597                goto out_err_nosb;
2598        }
2599
2600        if (s->s_fs_info != server) {
2601                nfs_free_server(server);
2602                server = NULL;
2603        } else {
2604                error = nfs_bdi_register(server);
2605                if (error) {
2606                        mntroot = ERR_PTR(error);
2607                        goto error_splat_super;
2608                }
2609                server->super = s;
2610        }
2611
2612        if (!s->s_root) {
2613                /* initial superblock/root creation */
2614                mount_info->fill_super(s, mount_info);
2615                nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2616        }
2617
2618        mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2619        if (IS_ERR(mntroot))
2620                goto error_splat_super;
2621
2622        error = mount_info->set_security(s, mntroot, mount_info);
2623        if (error)
2624                goto error_splat_root;
2625
2626        s->s_flags |= MS_ACTIVE;
2627
2628out:
2629        return mntroot;
2630
2631out_err_nosb:
2632        nfs_free_server(server);
2633        goto out;
2634
2635error_splat_root:
2636        dput(mntroot);
2637        mntroot = ERR_PTR(error);
2638error_splat_super:
2639        deactivate_locked_super(s);
2640        goto out;
2641}
2642EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2643
2644struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2645        int flags, const char *dev_name, void *raw_data)
2646{
2647        struct nfs_mount_info mount_info = {
2648                .fill_super = nfs_fill_super,
2649                .set_security = nfs_set_sb_security,
2650        };
2651        struct dentry *mntroot = ERR_PTR(-ENOMEM);
2652        struct nfs_subversion *nfs_mod;
2653        int error;
2654
2655        mount_info.parsed = nfs_alloc_parsed_mount_data();
2656        mount_info.mntfh = nfs_alloc_fhandle();
2657        if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2658                goto out;
2659
2660        /* Validate the mount data */
2661        error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2662        if (error == NFS_TEXT_DATA)
2663                error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2664        if (error < 0) {
2665                mntroot = ERR_PTR(error);
2666                goto out;
2667        }
2668
2669        nfs_mod = get_nfs_version(mount_info.parsed->version);
2670        if (IS_ERR(nfs_mod)) {
2671                mntroot = ERR_CAST(nfs_mod);
2672                goto out;
2673        }
2674
2675        mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2676
2677        put_nfs_version(nfs_mod);
2678out:
2679        nfs_free_parsed_mount_data(mount_info.parsed);
2680        nfs_free_fhandle(mount_info.mntfh);
2681        return mntroot;
2682}
2683EXPORT_SYMBOL_GPL(nfs_fs_mount);
2684
2685/*
2686 * Destroy an NFS2/3 superblock
2687 */
2688void nfs_kill_super(struct super_block *s)
2689{
2690        struct nfs_server *server = NFS_SB(s);
2691        dev_t dev = s->s_dev;
2692
2693        generic_shutdown_super(s);
2694
2695        nfs_fscache_release_super_cookie(s);
2696
2697        nfs_free_server(server);
2698        free_anon_bdev(dev);
2699}
2700EXPORT_SYMBOL_GPL(nfs_kill_super);
2701
2702/*
2703 * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2704 */
2705static struct dentry *
2706nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2707                const char *dev_name, void *raw_data)
2708{
2709        struct nfs_clone_mount *data = raw_data;
2710        struct nfs_mount_info mount_info = {
2711                .fill_super = nfs_clone_super,
2712                .set_security = nfs_clone_sb_security,
2713                .cloned = data,
2714        };
2715        struct nfs_server *server;
2716        struct dentry *mntroot = ERR_PTR(-ENOMEM);
2717        struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2718
2719        dprintk("--> nfs_xdev_mount()\n");
2720
2721        mount_info.mntfh = mount_info.cloned->fh;
2722
2723        /* create a new volume representation */
2724        server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2725
2726        if (IS_ERR(server))
2727                mntroot = ERR_CAST(server);
2728        else
2729                mntroot = nfs_fs_mount_common(server, flags,
2730                                dev_name, &mount_info, nfs_mod);
2731
2732        dprintk("<-- nfs_xdev_mount() = %ld\n",
2733                        IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2734        return mntroot;
2735}
2736
2737#if IS_ENABLED(CONFIG_NFS_V4)
2738
2739static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2740{
2741        args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2742                         NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2743}
2744
2745/*
2746 * Validate NFSv4 mount options
2747 */
2748static int nfs4_validate_mount_data(void *options,
2749                                    struct nfs_parsed_mount_data *args,
2750                                    const char *dev_name)
2751{
2752        struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2753        struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2754        char *c;
2755
2756        if (data == NULL)
2757                goto out_no_data;
2758
2759        args->version = 4;
2760
2761        switch (data->version) {
2762        case 1:
2763                if (data->host_addrlen > sizeof(args->nfs_server.address))
2764                        goto out_no_address;
2765                if (data->host_addrlen == 0)
2766                        goto out_no_address;
2767                args->nfs_server.addrlen = data->host_addrlen;
2768                if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2769                        return -EFAULT;
2770                if (!nfs_verify_server_address(sap))
2771                        goto out_no_address;
2772                args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2773
2774                if (data->auth_flavourlen) {
2775                        rpc_authflavor_t pseudoflavor;
2776                        if (data->auth_flavourlen > 1)
2777                                goto out_inval_auth;
2778                        if (copy_from_user(&pseudoflavor,
2779                                           data->auth_flavours,
2780                                           sizeof(pseudoflavor)))
2781                                return -EFAULT;
2782                        args->selected_flavor = pseudoflavor;
2783                } else
2784                        args->selected_flavor = RPC_AUTH_UNIX;
2785
2786                c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2787                if (IS_ERR(c))
2788                        return PTR_ERR(c);
2789                args->nfs_server.hostname = c;
2790
2791                c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2792                if (IS_ERR(c))
2793                        return PTR_ERR(c);
2794                args->nfs_server.export_path = c;
2795                dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2796
2797                c = strndup_user(data->client_addr.data, 16);
2798                if (IS_ERR(c))
2799                        return PTR_ERR(c);
2800                args->client_address = c;
2801
2802                /*
2803                 * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2804                 * can deal with.
2805                 */
2806
2807                args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2808                args->rsize     = data->rsize;
2809                args->wsize     = data->wsize;
2810                args->timeo     = data->timeo;
2811                args->retrans   = data->retrans;
2812                args->acregmin  = data->acregmin;
2813                args->acregmax  = data->acregmax;
2814                args->acdirmin  = data->acdirmin;
2815                args->acdirmax  = data->acdirmax;
2816                args->nfs_server.protocol = data->proto;
2817                nfs_validate_transport_protocol(args);
2818                if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2819                        goto out_invalid_transport_udp;
2820
2821                break;
2822        default:
2823                return NFS_TEXT_DATA;
2824        }
2825
2826        return 0;
2827
2828out_no_data:
2829        dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2830        return -EINVAL;
2831
2832out_inval_auth:
2833        dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2834                 data->auth_flavourlen);
2835        return -EINVAL;
2836
2837out_no_address:
2838        dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2839        return -EINVAL;
2840
2841out_invalid_transport_udp:
2842        dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2843        return -EINVAL;
2844}
2845
2846/*
2847 * NFS v4 module parameters need to stay in the
2848 * NFS client for backwards compatibility
2849 */
2850unsigned int nfs_callback_set_tcpport;
2851/* Default cache timeout is 10 minutes */
2852unsigned int nfs_idmap_cache_timeout = 600;
2853/* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2854bool nfs4_disable_idmapping = true;
2855unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2856unsigned short send_implementation_id = 1;
2857char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2858bool recover_lost_locks = false;
2859
2860EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2861EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2862EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2863EXPORT_SYMBOL_GPL(max_session_slots);
2864EXPORT_SYMBOL_GPL(send_implementation_id);
2865EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2866EXPORT_SYMBOL_GPL(recover_lost_locks);
2867
2868#define NFS_CALLBACK_MAXPORTNR (65535U)
2869
2870static int param_set_portnr(const char *val, const struct kernel_param *kp)
2871{
2872        unsigned long num;
2873        int ret;
2874
2875        if (!val)
2876                return -EINVAL;
2877        ret = kstrtoul(val, 0, &num);
2878        if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2879                return -EINVAL;
2880        *((unsigned int *)kp->arg) = num;
2881        return 0;
2882}
2883static const struct kernel_param_ops param_ops_portnr = {
2884        .set = param_set_portnr,
2885        .get = param_get_uint,
2886};
2887#define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2888
2889module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2890module_param(nfs_idmap_cache_timeout, int, 0644);
2891module_param(nfs4_disable_idmapping, bool, 0644);
2892module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2893                        NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2894MODULE_PARM_DESC(nfs4_disable_idmapping,
2895                "Turn off NFSv4 idmapping when using 'sec=sys'");
2896module_param(max_session_slots, ushort, 0644);
2897MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2898                "requests the client will negotiate");
2899module_param(send_implementation_id, ushort, 0644);
2900MODULE_PARM_DESC(send_implementation_id,
2901                "Send implementation ID with NFSv4.1 exchange_id");
2902MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2903
2904module_param(recover_lost_locks, bool, 0644);
2905MODULE_PARM_DESC(recover_lost_locks,
2906                 "If the server reports that a lock might be lost, "
2907                 "try to recover it risking data corruption.");
2908
2909
2910#endif /* CONFIG_NFS_V4 */
2911