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/stats.h>
  35#include <linux/sunrpc/metrics.h>
  36#include <linux/sunrpc/xprtsock.h>
  37#include <linux/sunrpc/xprtrdma.h>
  38#include <linux/nfs_fs.h>
  39#include <linux/nfs_mount.h>
  40#include <linux/nfs4_mount.h>
  41#include <linux/lockd/bind.h>
  42#include <linux/seq_file.h>
  43#include <linux/mount.h>
  44#include <linux/namei.h>
  45#include <linux/nfs_idmap.h>
  46#include <linux/vfs.h>
  47#include <linux/inet.h>
  48#include <linux/in6.h>
  49#include <linux/slab.h>
  50#include <net/ipv6.h>
  51#include <linux/netdevice.h>
  52#include <linux/nfs_xdr.h>
  53#include <linux/magic.h>
  54#include <linux/parser.h>
  55#include <linux/nsproxy.h>
  56#include <linux/rcupdate.h>
  57#include <linux/kthread.h>
  58
  59#include <asm/uaccess.h>
  60
  61#include "nfs4_fs.h"
  62#include "callback.h"
  63#include "delegation.h"
  64#include "iostat.h"
  65#include "internal.h"
  66#include "fscache.h"
  67#include "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
 195        Opt_xprt_err
 196};
 197
 198static const match_table_t nfs_xprt_protocol_tokens = {
 199        { Opt_xprt_udp, "udp" },
 200        { Opt_xprt_udp6, "udp6" },
 201        { Opt_xprt_tcp, "tcp" },
 202        { Opt_xprt_tcp6, "tcp6" },
 203        { Opt_xprt_rdma, "rdma" },
 204
 205        { Opt_xprt_err, NULL }
 206};
 207
 208enum {
 209        Opt_sec_none, Opt_sec_sys,
 210        Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
 211        Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
 212        Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
 213
 214        Opt_sec_err
 215};
 216
 217static const match_table_t nfs_secflavor_tokens = {
 218        { Opt_sec_none, "none" },
 219        { Opt_sec_none, "null" },
 220        { Opt_sec_sys, "sys" },
 221
 222        { Opt_sec_krb5, "krb5" },
 223        { Opt_sec_krb5i, "krb5i" },
 224        { Opt_sec_krb5p, "krb5p" },
 225
 226        { Opt_sec_lkey, "lkey" },
 227        { Opt_sec_lkeyi, "lkeyi" },
 228        { Opt_sec_lkeyp, "lkeyp" },
 229
 230        { Opt_sec_spkm, "spkm3" },
 231        { Opt_sec_spkmi, "spkm3i" },
 232        { Opt_sec_spkmp, "spkm3p" },
 233
 234        { Opt_sec_err, NULL }
 235};
 236
 237enum {
 238        Opt_lookupcache_all, Opt_lookupcache_positive,
 239        Opt_lookupcache_none,
 240
 241        Opt_lookupcache_err
 242};
 243
 244static match_table_t nfs_lookupcache_tokens = {
 245        { Opt_lookupcache_all, "all" },
 246        { Opt_lookupcache_positive, "pos" },
 247        { Opt_lookupcache_positive, "positive" },
 248        { Opt_lookupcache_none, "none" },
 249
 250        { Opt_lookupcache_err, NULL }
 251};
 252
 253enum {
 254        Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
 255        Opt_local_lock_none,
 256
 257        Opt_local_lock_err
 258};
 259
 260static match_table_t nfs_local_lock_tokens = {
 261        { Opt_local_lock_all, "all" },
 262        { Opt_local_lock_flock, "flock" },
 263        { Opt_local_lock_posix, "posix" },
 264        { Opt_local_lock_none, "none" },
 265
 266        { Opt_local_lock_err, NULL }
 267};
 268
 269enum {
 270        Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
 271        Opt_vers_4_1,
 272
 273        Opt_vers_err
 274};
 275
 276static match_table_t nfs_vers_tokens = {
 277        { Opt_vers_2, "2" },
 278        { Opt_vers_3, "3" },
 279        { Opt_vers_4, "4" },
 280        { Opt_vers_4_0, "4.0" },
 281        { Opt_vers_4_1, "4.1" },
 282
 283        { Opt_vers_err, NULL }
 284};
 285
 286static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
 287                int flags, const char *dev_name, void *raw_data);
 288
 289struct file_system_type nfs_fs_type = {
 290        .owner          = THIS_MODULE,
 291        .name           = "nfs",
 292        .mount          = nfs_fs_mount,
 293        .kill_sb        = nfs_kill_super,
 294        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 295};
 296EXPORT_SYMBOL_GPL(nfs_fs_type);
 297
 298struct file_system_type nfs_xdev_fs_type = {
 299        .owner          = THIS_MODULE,
 300        .name           = "nfs",
 301        .mount          = nfs_xdev_mount,
 302        .kill_sb        = nfs_kill_super,
 303        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 304};
 305
 306const struct super_operations nfs_sops = {
 307        .alloc_inode    = nfs_alloc_inode,
 308        .destroy_inode  = nfs_destroy_inode,
 309        .write_inode    = nfs_write_inode,
 310        .put_super      = nfs_put_super,
 311        .statfs         = nfs_statfs,
 312        .evict_inode    = nfs_evict_inode,
 313        .umount_begin   = nfs_umount_begin,
 314        .show_options   = nfs_show_options,
 315        .show_devname   = nfs_show_devname,
 316        .show_path      = nfs_show_path,
 317        .show_stats     = nfs_show_stats,
 318        .remount_fs     = nfs_remount,
 319};
 320EXPORT_SYMBOL_GPL(nfs_sops);
 321
 322#if IS_ENABLED(CONFIG_NFS_V4)
 323static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 324static int nfs4_validate_mount_data(void *options,
 325        struct nfs_parsed_mount_data *args, const char *dev_name);
 326
 327struct file_system_type nfs4_fs_type = {
 328        .owner          = THIS_MODULE,
 329        .name           = "nfs4",
 330        .mount          = nfs_fs_mount,
 331        .kill_sb        = nfs_kill_super,
 332        .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA,
 333};
 334EXPORT_SYMBOL_GPL(nfs4_fs_type);
 335
 336static int __init register_nfs4_fs(void)
 337{
 338        return register_filesystem(&nfs4_fs_type);
 339}
 340
 341static void unregister_nfs4_fs(void)
 342{
 343        unregister_filesystem(&nfs4_fs_type);
 344}
 345#else
 346static int __init register_nfs4_fs(void)
 347{
 348        return 0;
 349}
 350
 351static void unregister_nfs4_fs(void)
 352{
 353}
 354#endif
 355
 356static struct shrinker acl_shrinker = {
 357        .shrink         = nfs_access_cache_shrinker,
 358        .seeks          = DEFAULT_SEEKS,
 359};
 360
 361/*
 362 * Register the NFS filesystems
 363 */
 364int __init register_nfs_fs(void)
 365{
 366        int ret;
 367
 368        ret = register_filesystem(&nfs_fs_type);
 369        if (ret < 0)
 370                goto error_0;
 371
 372        ret = register_nfs4_fs();
 373        if (ret < 0)
 374                goto error_1;
 375
 376        ret = nfs_register_sysctl();
 377        if (ret < 0)
 378                goto error_2;
 379        register_shrinker(&acl_shrinker);
 380        return 0;
 381
 382error_2:
 383        unregister_nfs4_fs();
 384error_1:
 385        unregister_filesystem(&nfs_fs_type);
 386error_0:
 387        return ret;
 388}
 389
 390/*
 391 * Unregister the NFS filesystems
 392 */
 393void __exit unregister_nfs_fs(void)
 394{
 395        unregister_shrinker(&acl_shrinker);
 396        nfs_unregister_sysctl();
 397        unregister_nfs4_fs();
 398        unregister_filesystem(&nfs_fs_type);
 399}
 400
 401void nfs_sb_active(struct super_block *sb)
 402{
 403        struct nfs_server *server = NFS_SB(sb);
 404
 405        if (atomic_inc_return(&server->active) == 1)
 406                atomic_inc(&sb->s_active);
 407}
 408EXPORT_SYMBOL_GPL(nfs_sb_active);
 409
 410void nfs_sb_deactive(struct super_block *sb)
 411{
 412        struct nfs_server *server = NFS_SB(sb);
 413
 414        if (atomic_dec_and_test(&server->active))
 415                deactivate_super(sb);
 416}
 417EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 418
 419static int nfs_deactivate_super_async_work(void *ptr)
 420{
 421        struct super_block *sb = ptr;
 422
 423        deactivate_super(sb);
 424        module_put_and_exit(0);
 425        return 0;
 426}
 427
 428/*
 429 * same effect as deactivate_super, but will do final unmount in kthread
 430 * context
 431 */
 432static void nfs_deactivate_super_async(struct super_block *sb)
 433{
 434        struct task_struct *task;
 435        char buf[INET6_ADDRSTRLEN + 1];
 436        struct nfs_server *server = NFS_SB(sb);
 437        struct nfs_client *clp = server->nfs_client;
 438
 439        if (!atomic_add_unless(&sb->s_active, -1, 1)) {
 440                rcu_read_lock();
 441                snprintf(buf, sizeof(buf),
 442                        rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
 443                rcu_read_unlock();
 444
 445                __module_get(THIS_MODULE);
 446                task = kthread_run(nfs_deactivate_super_async_work, sb,
 447                                "%s-deactivate-super", buf);
 448                if (IS_ERR(task)) {
 449                        pr_err("%s: kthread_run: %ld\n",
 450                                __func__, PTR_ERR(task));
 451                        /* make synchronous call and hope for the best */
 452                        deactivate_super(sb);
 453                        module_put(THIS_MODULE);
 454                }
 455        }
 456}
 457
 458void nfs_sb_deactive_async(struct super_block *sb)
 459{
 460        struct nfs_server *server = NFS_SB(sb);
 461
 462        if (atomic_dec_and_test(&server->active))
 463                nfs_deactivate_super_async(sb);
 464}
 465EXPORT_SYMBOL_GPL(nfs_sb_deactive_async);
 466
 467/*
 468 * Deliver file system statistics to userspace
 469 */
 470int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 471{
 472        struct nfs_server *server = NFS_SB(dentry->d_sb);
 473        unsigned char blockbits;
 474        unsigned long blockres;
 475        struct nfs_fh *fh = NFS_FH(dentry->d_inode);
 476        struct nfs_fsstat res;
 477        int error = -ENOMEM;
 478
 479        res.fattr = nfs_alloc_fattr();
 480        if (res.fattr == NULL)
 481                goto out_err;
 482
 483        error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
 484        if (unlikely(error == -ESTALE)) {
 485                struct dentry *pd_dentry;
 486
 487                pd_dentry = dget_parent(dentry);
 488                if (pd_dentry != NULL) {
 489                        nfs_zap_caches(pd_dentry->d_inode);
 490                        dput(pd_dentry);
 491                }
 492        }
 493        nfs_free_fattr(res.fattr);
 494        if (error < 0)
 495                goto out_err;
 496
 497        buf->f_type = NFS_SUPER_MAGIC;
 498
 499        /*
 500         * Current versions of glibc do not correctly handle the
 501         * case where f_frsize != f_bsize.  Eventually we want to
 502         * report the value of wtmult in this field.
 503         */
 504        buf->f_frsize = dentry->d_sb->s_blocksize;
 505
 506        /*
 507         * On most *nix systems, f_blocks, f_bfree, and f_bavail
 508         * are reported in units of f_frsize.  Linux hasn't had
 509         * an f_frsize field in its statfs struct until recently,
 510         * thus historically Linux's sys_statfs reports these
 511         * fields in units of f_bsize.
 512         */
 513        buf->f_bsize = dentry->d_sb->s_blocksize;
 514        blockbits = dentry->d_sb->s_blocksize_bits;
 515        blockres = (1 << blockbits) - 1;
 516        buf->f_blocks = (res.tbytes + blockres) >> blockbits;
 517        buf->f_bfree = (res.fbytes + blockres) >> blockbits;
 518        buf->f_bavail = (res.abytes + blockres) >> blockbits;
 519
 520        buf->f_files = res.tfiles;
 521        buf->f_ffree = res.afiles;
 522
 523        buf->f_namelen = server->namelen;
 524
 525        return 0;
 526
 527 out_err:
 528        dprintk("%s: statfs error = %d\n", __func__, -error);
 529        return error;
 530}
 531EXPORT_SYMBOL_GPL(nfs_statfs);
 532
 533/*
 534 * Map the security flavour number to a name
 535 */
 536static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
 537{
 538        static const struct {
 539                rpc_authflavor_t flavour;
 540                const char *str;
 541        } sec_flavours[] = {
 542                { RPC_AUTH_NULL, "null" },
 543                { RPC_AUTH_UNIX, "sys" },
 544                { RPC_AUTH_GSS_KRB5, "krb5" },
 545                { RPC_AUTH_GSS_KRB5I, "krb5i" },
 546                { RPC_AUTH_GSS_KRB5P, "krb5p" },
 547                { RPC_AUTH_GSS_LKEY, "lkey" },
 548                { RPC_AUTH_GSS_LKEYI, "lkeyi" },
 549                { RPC_AUTH_GSS_LKEYP, "lkeyp" },
 550                { RPC_AUTH_GSS_SPKM, "spkm" },
 551                { RPC_AUTH_GSS_SPKMI, "spkmi" },
 552                { RPC_AUTH_GSS_SPKMP, "spkmp" },
 553                { UINT_MAX, "unknown" }
 554        };
 555        int i;
 556
 557        for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
 558                if (sec_flavours[i].flavour == flavour)
 559                        break;
 560        }
 561        return sec_flavours[i].str;
 562}
 563
 564static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
 565                                  int showdefaults)
 566{
 567        struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
 568
 569        seq_printf(m, ",mountproto=");
 570        switch (sap->sa_family) {
 571        case AF_INET:
 572                switch (nfss->mountd_protocol) {
 573                case IPPROTO_UDP:
 574                        seq_printf(m, RPCBIND_NETID_UDP);
 575                        break;
 576                case IPPROTO_TCP:
 577                        seq_printf(m, RPCBIND_NETID_TCP);
 578                        break;
 579                default:
 580                        if (showdefaults)
 581                                seq_printf(m, "auto");
 582                }
 583                break;
 584        case AF_INET6:
 585                switch (nfss->mountd_protocol) {
 586                case IPPROTO_UDP:
 587                        seq_printf(m, RPCBIND_NETID_UDP6);
 588                        break;
 589                case IPPROTO_TCP:
 590                        seq_printf(m, RPCBIND_NETID_TCP6);
 591                        break;
 592                default:
 593                        if (showdefaults)
 594                                seq_printf(m, "auto");
 595                }
 596                break;
 597        default:
 598                if (showdefaults)
 599                        seq_printf(m, "auto");
 600        }
 601}
 602
 603static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
 604                                    int showdefaults)
 605{
 606        struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
 607
 608        if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
 609                return;
 610
 611        switch (sap->sa_family) {
 612        case AF_INET: {
 613                struct sockaddr_in *sin = (struct sockaddr_in *)sap;
 614                seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
 615                break;
 616        }
 617        case AF_INET6: {
 618                struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
 619                seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
 620                break;
 621        }
 622        default:
 623                if (showdefaults)
 624                        seq_printf(m, ",mountaddr=unspecified");
 625        }
 626
 627        if (nfss->mountd_version || showdefaults)
 628                seq_printf(m, ",mountvers=%u", nfss->mountd_version);
 629        if ((nfss->mountd_port &&
 630                nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
 631                showdefaults)
 632                seq_printf(m, ",mountport=%u", nfss->mountd_port);
 633
 634        nfs_show_mountd_netid(m, nfss, showdefaults);
 635}
 636
 637#if IS_ENABLED(CONFIG_NFS_V4)
 638static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 639                                    int showdefaults)
 640{
 641        struct nfs_client *clp = nfss->nfs_client;
 642
 643        seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
 644}
 645#else
 646static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
 647                                    int showdefaults)
 648{
 649}
 650#endif
 651
 652static void nfs_show_nfs_version(struct seq_file *m,
 653                unsigned int version,
 654                unsigned int minorversion)
 655{
 656        seq_printf(m, ",vers=%u", version);
 657        if (version == 4)
 658                seq_printf(m, ".%u", minorversion);
 659}
 660
 661/*
 662 * Describe the mount options in force on this server representation
 663 */
 664static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
 665                                   int showdefaults)
 666{
 667        static const struct proc_nfs_info {
 668                int flag;
 669                const char *str;
 670                const char *nostr;
 671        } nfs_info[] = {
 672                { NFS_MOUNT_SOFT, ",soft", ",hard" },
 673                { NFS_MOUNT_POSIX, ",posix", "" },
 674                { NFS_MOUNT_NOCTO, ",nocto", "" },
 675                { NFS_MOUNT_NOAC, ",noac", "" },
 676                { NFS_MOUNT_NONLM, ",nolock", "" },
 677                { NFS_MOUNT_NOACL, ",noacl", "" },
 678                { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 679                { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
 680                { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
 681                { 0, NULL, NULL }
 682        };
 683        const struct proc_nfs_info *nfs_infop;
 684        struct nfs_client *clp = nfss->nfs_client;
 685        u32 version = clp->rpc_ops->version;
 686        int local_flock, local_fcntl;
 687
 688        nfs_show_nfs_version(m, version, clp->cl_minorversion);
 689        seq_printf(m, ",rsize=%u", nfss->rsize);
 690        seq_printf(m, ",wsize=%u", nfss->wsize);
 691        if (nfss->bsize != 0)
 692                seq_printf(m, ",bsize=%u", nfss->bsize);
 693        seq_printf(m, ",namlen=%u", nfss->namelen);
 694        if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
 695                seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
 696        if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
 697                seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
 698        if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
 699                seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
 700        if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
 701                seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
 702        for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
 703                if (nfss->flags & nfs_infop->flag)
 704                        seq_puts(m, nfs_infop->str);
 705                else
 706                        seq_puts(m, nfs_infop->nostr);
 707        }
 708        rcu_read_lock();
 709        seq_printf(m, ",proto=%s",
 710                   rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
 711        rcu_read_unlock();
 712        if (version == 4) {
 713                if (nfss->port != NFS_PORT)
 714                        seq_printf(m, ",port=%u", nfss->port);
 715        } else
 716                if (nfss->port)
 717                        seq_printf(m, ",port=%u", nfss->port);
 718
 719        seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
 720        seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
 721        seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
 722
 723        if (version != 4)
 724                nfs_show_mountd_options(m, nfss, showdefaults);
 725        else
 726                nfs_show_nfsv4_options(m, nfss, showdefaults);
 727
 728        if (nfss->options & NFS_OPTION_FSCACHE)
 729                seq_printf(m, ",fsc");
 730
 731        if (nfss->options & NFS_OPTION_MIGRATION)
 732                seq_printf(m, ",migration");
 733
 734        if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
 735                if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
 736                        seq_printf(m, ",lookupcache=none");
 737                else
 738                        seq_printf(m, ",lookupcache=pos");
 739        }
 740
 741        local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
 742        local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
 743
 744        if (!local_flock && !local_fcntl)
 745                seq_printf(m, ",local_lock=none");
 746        else if (local_flock && local_fcntl)
 747                seq_printf(m, ",local_lock=all");
 748        else if (local_flock)
 749                seq_printf(m, ",local_lock=flock");
 750        else
 751                seq_printf(m, ",local_lock=posix");
 752}
 753
 754/*
 755 * Describe the mount options on this VFS mountpoint
 756 */
 757int nfs_show_options(struct seq_file *m, struct dentry *root)
 758{
 759        struct nfs_server *nfss = NFS_SB(root->d_sb);
 760
 761        nfs_show_mount_options(m, nfss, 0);
 762
 763        rcu_read_lock();
 764        seq_printf(m, ",addr=%s",
 765                        rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
 766                                                        RPC_DISPLAY_ADDR));
 767        rcu_read_unlock();
 768
 769        return 0;
 770}
 771EXPORT_SYMBOL_GPL(nfs_show_options);
 772
 773#if IS_ENABLED(CONFIG_NFS_V4)
 774#ifdef CONFIG_NFS_V4_1
 775static void show_sessions(struct seq_file *m, struct nfs_server *server)
 776{
 777        if (nfs4_has_session(server->nfs_client))
 778                seq_printf(m, ",sessions");
 779}
 780#else
 781static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
 782#endif
 783#endif
 784
 785#ifdef CONFIG_NFS_V4_1
 786static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 787{
 788        seq_printf(m, ",pnfs=");
 789        if (server->pnfs_curr_ld)
 790                seq_printf(m, "%s", server->pnfs_curr_ld->name);
 791        else
 792                seq_printf(m, "not configured");
 793}
 794
 795static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 796{
 797        if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
 798                struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
 799                seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
 800                           "date='%llu,%u'",
 801                           impl_id->name, impl_id->domain,
 802                           impl_id->date.seconds, impl_id->date.nseconds);
 803        }
 804}
 805#else
 806#if IS_ENABLED(CONFIG_NFS_V4)
 807static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 808{
 809}
 810#endif
 811static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
 812{
 813}
 814#endif
 815
 816int nfs_show_devname(struct seq_file *m, struct dentry *root)
 817{
 818        char *page = (char *) __get_free_page(GFP_KERNEL);
 819        char *devname, *dummy;
 820        int err = 0;
 821        if (!page)
 822                return -ENOMEM;
 823        devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
 824        if (IS_ERR(devname))
 825                err = PTR_ERR(devname);
 826        else
 827                seq_escape(m, devname, " \t\n\\");
 828        free_page((unsigned long)page);
 829        return err;
 830}
 831EXPORT_SYMBOL_GPL(nfs_show_devname);
 832
 833int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 834{
 835        seq_puts(m, "/");
 836        return 0;
 837}
 838EXPORT_SYMBOL_GPL(nfs_show_path);
 839
 840/*
 841 * Present statistical information for this VFS mountpoint
 842 */
 843int nfs_show_stats(struct seq_file *m, struct dentry *root)
 844{
 845        int i, cpu;
 846        struct nfs_server *nfss = NFS_SB(root->d_sb);
 847        struct rpc_auth *auth = nfss->client->cl_auth;
 848        struct nfs_iostats totals = { };
 849
 850        seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
 851
 852        /*
 853         * Display all mount option settings
 854         */
 855        seq_printf(m, "\n\topts:\t");
 856        seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
 857        seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
 858        seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
 859        seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
 860        nfs_show_mount_options(m, nfss, 1);
 861
 862        seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
 863
 864        show_implementation_id(m, nfss);
 865
 866        seq_printf(m, "\n\tcaps:\t");
 867        seq_printf(m, "caps=0x%x", nfss->caps);
 868        seq_printf(m, ",wtmult=%u", nfss->wtmult);
 869        seq_printf(m, ",dtsize=%u", nfss->dtsize);
 870        seq_printf(m, ",bsize=%u", nfss->bsize);
 871        seq_printf(m, ",namlen=%u", nfss->namelen);
 872
 873#if IS_ENABLED(CONFIG_NFS_V4)
 874        if (nfss->nfs_client->rpc_ops->version == 4) {
 875                seq_printf(m, "\n\tnfsv4:\t");
 876                seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
 877                seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
 878                seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
 879                show_sessions(m, nfss);
 880                show_pnfs(m, nfss);
 881        }
 882#endif
 883
 884        /*
 885         * Display security flavor in effect for this mount
 886         */
 887        seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
 888        if (auth->au_flavor)
 889                seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
 890
 891        /*
 892         * Display superblock I/O counters
 893         */
 894        for_each_possible_cpu(cpu) {
 895                struct nfs_iostats *stats;
 896
 897                preempt_disable();
 898                stats = per_cpu_ptr(nfss->io_stats, cpu);
 899
 900                for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 901                        totals.events[i] += stats->events[i];
 902                for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 903                        totals.bytes[i] += stats->bytes[i];
 904#ifdef CONFIG_NFS_FSCACHE
 905                for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 906                        totals.fscache[i] += stats->fscache[i];
 907#endif
 908
 909                preempt_enable();
 910        }
 911
 912        seq_printf(m, "\n\tevents:\t");
 913        for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
 914                seq_printf(m, "%lu ", totals.events[i]);
 915        seq_printf(m, "\n\tbytes:\t");
 916        for (i = 0; i < __NFSIOS_BYTESMAX; i++)
 917                seq_printf(m, "%Lu ", totals.bytes[i]);
 918#ifdef CONFIG_NFS_FSCACHE
 919        if (nfss->options & NFS_OPTION_FSCACHE) {
 920                seq_printf(m, "\n\tfsc:\t");
 921                for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
 922                        seq_printf(m, "%Lu ", totals.bytes[i]);
 923        }
 924#endif
 925        seq_printf(m, "\n");
 926
 927        rpc_print_iostats(m, nfss->client);
 928
 929        return 0;
 930}
 931EXPORT_SYMBOL_GPL(nfs_show_stats);
 932
 933/*
 934 * Begin unmount by attempting to remove all automounted mountpoints we added
 935 * in response to xdev traversals and referrals
 936 */
 937void nfs_umount_begin(struct super_block *sb)
 938{
 939        struct nfs_server *server;
 940        struct rpc_clnt *rpc;
 941
 942        server = NFS_SB(sb);
 943        /* -EIO all pending I/O */
 944        rpc = server->client_acl;
 945        if (!IS_ERR(rpc))
 946                rpc_killall_tasks(rpc);
 947        rpc = server->client;
 948        if (!IS_ERR(rpc))
 949                rpc_killall_tasks(rpc);
 950}
 951EXPORT_SYMBOL_GPL(nfs_umount_begin);
 952
 953static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 954{
 955        struct nfs_parsed_mount_data *data;
 956
 957        data = kzalloc(sizeof(*data), GFP_KERNEL);
 958        if (data) {
 959                data->acregmin          = NFS_DEF_ACREGMIN;
 960                data->acregmax          = NFS_DEF_ACREGMAX;
 961                data->acdirmin          = NFS_DEF_ACDIRMIN;
 962                data->acdirmax          = NFS_DEF_ACDIRMAX;
 963                data->mount_server.port = NFS_UNSPEC_PORT;
 964                data->nfs_server.port   = NFS_UNSPEC_PORT;
 965                data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 966                data->auth_flavors[0]   = RPC_AUTH_UNIX;
 967                data->auth_flavor_len   = 1;
 968                data->minorversion      = 0;
 969                data->need_mount        = true;
 970                data->net               = current->nsproxy->net_ns;
 971                security_init_mnt_opts(&data->lsm_opts);
 972        }
 973        return data;
 974}
 975
 976static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
 977{
 978        if (data) {
 979                kfree(data->client_address);
 980                kfree(data->mount_server.hostname);
 981                kfree(data->nfs_server.export_path);
 982                kfree(data->nfs_server.hostname);
 983                kfree(data->fscache_uniq);
 984                security_free_mnt_opts(&data->lsm_opts);
 985                kfree(data);
 986        }
 987}
 988
 989/*
 990 * Sanity-check a server address provided by the mount command.
 991 *
 992 * Address family must be initialized, and address must not be
 993 * the ANY address for that family.
 994 */
 995static int nfs_verify_server_address(struct sockaddr *addr)
 996{
 997        switch (addr->sa_family) {
 998        case AF_INET: {
 999                struct sockaddr_in *sa = (struct sockaddr_in *)addr;
1000                return sa->sin_addr.s_addr != htonl(INADDR_ANY);
1001        }
1002        case AF_INET6: {
1003                struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
1004                return !ipv6_addr_any(sa);
1005        }
1006        }
1007
1008        dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
1009        return 0;
1010}
1011
1012/*
1013 * Select between a default port value and a user-specified port value.
1014 * If a zero value is set, then autobind will be used.
1015 */
1016static void nfs_set_port(struct sockaddr *sap, int *port,
1017                                 const unsigned short default_port)
1018{
1019        if (*port == NFS_UNSPEC_PORT)
1020                *port = default_port;
1021
1022        rpc_set_port(sap, *port);
1023}
1024
1025/*
1026 * Sanity check the NFS transport protocol.
1027 *
1028 */
1029static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
1030{
1031        switch (mnt->nfs_server.protocol) {
1032        case XPRT_TRANSPORT_UDP:
1033        case XPRT_TRANSPORT_TCP:
1034        case XPRT_TRANSPORT_RDMA:
1035                break;
1036        default:
1037                mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1038        }
1039}
1040
1041/*
1042 * For text based NFSv2/v3 mounts, the mount protocol transport default
1043 * settings should depend upon the specified NFS transport.
1044 */
1045static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1046{
1047        nfs_validate_transport_protocol(mnt);
1048
1049        if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1050            mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1051                        return;
1052        switch (mnt->nfs_server.protocol) {
1053        case XPRT_TRANSPORT_UDP:
1054                mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1055                break;
1056        case XPRT_TRANSPORT_TCP:
1057        case XPRT_TRANSPORT_RDMA:
1058                mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1059        }
1060}
1061
1062/*
1063 * Parse the value of the 'sec=' option.
1064 */
1065static int nfs_parse_security_flavors(char *value,
1066                                      struct nfs_parsed_mount_data *mnt)
1067{
1068        substring_t args[MAX_OPT_ARGS];
1069
1070        dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1071
1072        switch (match_token(value, nfs_secflavor_tokens, args)) {
1073        case Opt_sec_none:
1074                mnt->auth_flavors[0] = RPC_AUTH_NULL;
1075                break;
1076        case Opt_sec_sys:
1077                mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1078                break;
1079        case Opt_sec_krb5:
1080                mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1081                break;
1082        case Opt_sec_krb5i:
1083                mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1084                break;
1085        case Opt_sec_krb5p:
1086                mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1087                break;
1088        case Opt_sec_lkey:
1089                mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1090                break;
1091        case Opt_sec_lkeyi:
1092                mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1093                break;
1094        case Opt_sec_lkeyp:
1095                mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1096                break;
1097        case Opt_sec_spkm:
1098                mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1099                break;
1100        case Opt_sec_spkmi:
1101                mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1102                break;
1103        case Opt_sec_spkmp:
1104                mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1105                break;
1106        default:
1107                return 0;
1108        }
1109
1110        mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1111        mnt->auth_flavor_len = 1;
1112        return 1;
1113}
1114
1115static int nfs_parse_version_string(char *string,
1116                struct nfs_parsed_mount_data *mnt,
1117                substring_t *args)
1118{
1119        mnt->flags &= ~NFS_MOUNT_VER3;
1120        switch (match_token(string, nfs_vers_tokens, args)) {
1121        case Opt_vers_2:
1122                mnt->version = 2;
1123                break;
1124        case Opt_vers_3:
1125                mnt->flags |= NFS_MOUNT_VER3;
1126                mnt->version = 3;
1127                break;
1128        case Opt_vers_4:
1129                /* Backward compatibility option. In future,
1130                 * the mount program should always supply
1131                 * a NFSv4 minor version number.
1132                 */
1133                mnt->version = 4;
1134                break;
1135        case Opt_vers_4_0:
1136                mnt->version = 4;
1137                mnt->minorversion = 0;
1138                break;
1139        case Opt_vers_4_1:
1140                mnt->version = 4;
1141                mnt->minorversion = 1;
1142                break;
1143        default:
1144                return 0;
1145        }
1146        return 1;
1147}
1148
1149static int nfs_get_option_str(substring_t args[], char **option)
1150{
1151        kfree(*option);
1152        *option = match_strdup(args);
1153        return !option;
1154}
1155
1156static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1157{
1158        int rc;
1159        char *string;
1160
1161        string = match_strdup(args);
1162        if (string == NULL)
1163                return -ENOMEM;
1164        rc = kstrtoul(string, 10, option);
1165        kfree(string);
1166
1167        return rc;
1168}
1169
1170/*
1171 * Error-check and convert a string of mount options from user space into
1172 * a data structure.  The whole mount string is processed; bad options are
1173 * skipped as they are encountered.  If there were no errors, return 1;
1174 * otherwise return 0 (zero).
1175 */
1176static int nfs_parse_mount_options(char *raw,
1177                                   struct nfs_parsed_mount_data *mnt)
1178{
1179        char *p, *string, *secdata;
1180        int rc, sloppy = 0, invalid_option = 0;
1181        unsigned short protofamily = AF_UNSPEC;
1182        unsigned short mountfamily = AF_UNSPEC;
1183
1184        if (!raw) {
1185                dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1186                return 1;
1187        }
1188        dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1189
1190        secdata = alloc_secdata();
1191        if (!secdata)
1192                goto out_nomem;
1193
1194        rc = security_sb_copy_data(raw, secdata);
1195        if (rc)
1196                goto out_security_failure;
1197
1198        rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1199        if (rc)
1200                goto out_security_failure;
1201
1202        free_secdata(secdata);
1203
1204        while ((p = strsep(&raw, ",")) != NULL) {
1205                substring_t args[MAX_OPT_ARGS];
1206                unsigned long option;
1207                int token;
1208
1209                if (!*p)
1210                        continue;
1211
1212                dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1213
1214                token = match_token(p, nfs_mount_option_tokens, args);
1215                switch (token) {
1216
1217                /*
1218                 * boolean options:  foo/nofoo
1219                 */
1220                case Opt_soft:
1221                        mnt->flags |= NFS_MOUNT_SOFT;
1222                        break;
1223                case Opt_hard:
1224                        mnt->flags &= ~NFS_MOUNT_SOFT;
1225                        break;
1226                case Opt_posix:
1227                        mnt->flags |= NFS_MOUNT_POSIX;
1228                        break;
1229                case Opt_noposix:
1230                        mnt->flags &= ~NFS_MOUNT_POSIX;
1231                        break;
1232                case Opt_cto:
1233                        mnt->flags &= ~NFS_MOUNT_NOCTO;
1234                        break;
1235                case Opt_nocto:
1236                        mnt->flags |= NFS_MOUNT_NOCTO;
1237                        break;
1238                case Opt_ac:
1239                        mnt->flags &= ~NFS_MOUNT_NOAC;
1240                        break;
1241                case Opt_noac:
1242                        mnt->flags |= NFS_MOUNT_NOAC;
1243                        break;
1244                case Opt_lock:
1245                        mnt->flags &= ~NFS_MOUNT_NONLM;
1246                        mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1247                                        NFS_MOUNT_LOCAL_FCNTL);
1248                        break;
1249                case Opt_nolock:
1250                        mnt->flags |= NFS_MOUNT_NONLM;
1251                        mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1252                                       NFS_MOUNT_LOCAL_FCNTL);
1253                        break;
1254                case Opt_udp:
1255                        mnt->flags &= ~NFS_MOUNT_TCP;
1256                        mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1257                        break;
1258                case Opt_tcp:
1259                        mnt->flags |= NFS_MOUNT_TCP;
1260                        mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1261                        break;
1262                case Opt_rdma:
1263                        mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1264                        mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1265                        xprt_load_transport(p);
1266                        break;
1267                case Opt_acl:
1268                        mnt->flags &= ~NFS_MOUNT_NOACL;
1269                        break;
1270                case Opt_noacl:
1271                        mnt->flags |= NFS_MOUNT_NOACL;
1272                        break;
1273                case Opt_rdirplus:
1274                        mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1275                        break;
1276                case Opt_nordirplus:
1277                        mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1278                        break;
1279                case Opt_sharecache:
1280                        mnt->flags &= ~NFS_MOUNT_UNSHARED;
1281                        break;
1282                case Opt_nosharecache:
1283                        mnt->flags |= NFS_MOUNT_UNSHARED;
1284                        break;
1285                case Opt_resvport:
1286                        mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1287                        break;
1288                case Opt_noresvport:
1289                        mnt->flags |= NFS_MOUNT_NORESVPORT;
1290                        break;
1291                case Opt_fscache:
1292                        mnt->options |= NFS_OPTION_FSCACHE;
1293                        kfree(mnt->fscache_uniq);
1294                        mnt->fscache_uniq = NULL;
1295                        break;
1296                case Opt_nofscache:
1297                        mnt->options &= ~NFS_OPTION_FSCACHE;
1298                        kfree(mnt->fscache_uniq);
1299                        mnt->fscache_uniq = NULL;
1300                        break;
1301                case Opt_migration:
1302                        mnt->options |= NFS_OPTION_MIGRATION;
1303                        break;
1304                case Opt_nomigration:
1305                        mnt->options &= NFS_OPTION_MIGRATION;
1306                        break;
1307
1308                /*
1309                 * options that take numeric values
1310                 */
1311                case Opt_port:
1312                        if (nfs_get_option_ul(args, &option) ||
1313                            option > USHRT_MAX)
1314                                goto out_invalid_value;
1315                        mnt->nfs_server.port = option;
1316                        break;
1317                case Opt_rsize:
1318                        if (nfs_get_option_ul(args, &option))
1319                                goto out_invalid_value;
1320                        mnt->rsize = option;
1321                        break;
1322                case Opt_wsize:
1323                        if (nfs_get_option_ul(args, &option))
1324                                goto out_invalid_value;
1325                        mnt->wsize = option;
1326                        break;
1327                case Opt_bsize:
1328                        if (nfs_get_option_ul(args, &option))
1329                                goto out_invalid_value;
1330                        mnt->bsize = option;
1331                        break;
1332                case Opt_timeo:
1333                        if (nfs_get_option_ul(args, &option) || option == 0)
1334                                goto out_invalid_value;
1335                        mnt->timeo = option;
1336                        break;
1337                case Opt_retrans:
1338                        if (nfs_get_option_ul(args, &option) || option == 0)
1339                                goto out_invalid_value;
1340                        mnt->retrans = option;
1341                        break;
1342                case Opt_acregmin:
1343                        if (nfs_get_option_ul(args, &option))
1344                                goto out_invalid_value;
1345                        mnt->acregmin = option;
1346                        break;
1347                case Opt_acregmax:
1348                        if (nfs_get_option_ul(args, &option))
1349                                goto out_invalid_value;
1350                        mnt->acregmax = option;
1351                        break;
1352                case Opt_acdirmin:
1353                        if (nfs_get_option_ul(args, &option))
1354                                goto out_invalid_value;
1355                        mnt->acdirmin = option;
1356                        break;
1357                case Opt_acdirmax:
1358                        if (nfs_get_option_ul(args, &option))
1359                                goto out_invalid_value;
1360                        mnt->acdirmax = option;
1361                        break;
1362                case Opt_actimeo:
1363                        if (nfs_get_option_ul(args, &option))
1364                                goto out_invalid_value;
1365                        mnt->acregmin = mnt->acregmax =
1366                        mnt->acdirmin = mnt->acdirmax = option;
1367                        break;
1368                case Opt_namelen:
1369                        if (nfs_get_option_ul(args, &option))
1370                                goto out_invalid_value;
1371                        mnt->namlen = option;
1372                        break;
1373                case Opt_mountport:
1374                        if (nfs_get_option_ul(args, &option) ||
1375                            option > USHRT_MAX)
1376                                goto out_invalid_value;
1377                        mnt->mount_server.port = option;
1378                        break;
1379                case Opt_mountvers:
1380                        if (nfs_get_option_ul(args, &option) ||
1381                            option < NFS_MNT_VERSION ||
1382                            option > NFS_MNT3_VERSION)
1383                                goto out_invalid_value;
1384                        mnt->mount_server.version = option;
1385                        break;
1386                case Opt_minorversion:
1387                        if (nfs_get_option_ul(args, &option))
1388                                goto out_invalid_value;
1389                        if (option > NFS4_MAX_MINOR_VERSION)
1390                                goto out_invalid_value;
1391                        mnt->minorversion = option;
1392                        break;
1393
1394                /*
1395                 * options that take text values
1396                 */
1397                case Opt_nfsvers:
1398                        string = match_strdup(args);
1399                        if (string == NULL)
1400                                goto out_nomem;
1401                        rc = nfs_parse_version_string(string, mnt, args);
1402                        kfree(string);
1403                        if (!rc)
1404                                goto out_invalid_value;
1405                        break;
1406                case Opt_sec:
1407                        string = match_strdup(args);
1408                        if (string == NULL)
1409                                goto out_nomem;
1410                        rc = nfs_parse_security_flavors(string, mnt);
1411                        kfree(string);
1412                        if (!rc) {
1413                                dfprintk(MOUNT, "NFS:   unrecognized "
1414                                                "security flavor\n");
1415                                return 0;
1416                        }
1417                        break;
1418                case Opt_proto:
1419                        string = match_strdup(args);
1420                        if (string == NULL)
1421                                goto out_nomem;
1422                        token = match_token(string,
1423                                            nfs_xprt_protocol_tokens, args);
1424
1425                        protofamily = AF_INET;
1426                        switch (token) {
1427                        case Opt_xprt_udp6:
1428                                protofamily = AF_INET6;
1429                        case Opt_xprt_udp:
1430                                mnt->flags &= ~NFS_MOUNT_TCP;
1431                                mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1432                                break;
1433                        case Opt_xprt_tcp6:
1434                                protofamily = AF_INET6;
1435                        case Opt_xprt_tcp:
1436                                mnt->flags |= NFS_MOUNT_TCP;
1437                                mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1438                                break;
1439                        case Opt_xprt_rdma:
1440                                /* vector side protocols to TCP */
1441                                mnt->flags |= NFS_MOUNT_TCP;
1442                                mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1443                                xprt_load_transport(string);
1444                                break;
1445                        default:
1446                                dfprintk(MOUNT, "NFS:   unrecognized "
1447                                                "transport protocol\n");
1448                                kfree(string);
1449                                return 0;
1450                        }
1451                        kfree(string);
1452                        break;
1453                case Opt_mountproto:
1454                        string = match_strdup(args);
1455                        if (string == NULL)
1456                                goto out_nomem;
1457                        token = match_token(string,
1458                                            nfs_xprt_protocol_tokens, args);
1459                        kfree(string);
1460
1461                        mountfamily = AF_INET;
1462                        switch (token) {
1463                        case Opt_xprt_udp6:
1464                                mountfamily = AF_INET6;
1465                        case Opt_xprt_udp:
1466                                mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1467                                break;
1468                        case Opt_xprt_tcp6:
1469                                mountfamily = AF_INET6;
1470                        case Opt_xprt_tcp:
1471                                mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1472                                break;
1473                        case Opt_xprt_rdma: /* not used for side protocols */
1474                        default:
1475                                dfprintk(MOUNT, "NFS:   unrecognized "
1476                                                "transport protocol\n");
1477                                return 0;
1478                        }
1479                        break;
1480                case Opt_addr:
1481                        string = match_strdup(args);
1482                        if (string == NULL)
1483                                goto out_nomem;
1484                        mnt->nfs_server.addrlen =
1485                                rpc_pton(mnt->net, string, strlen(string),
1486                                        (struct sockaddr *)
1487                                        &mnt->nfs_server.address,
1488                                        sizeof(mnt->nfs_server.address));
1489                        kfree(string);
1490                        if (mnt->nfs_server.addrlen == 0)
1491                                goto out_invalid_address;
1492                        break;
1493                case Opt_clientaddr:
1494                        if (nfs_get_option_str(args, &mnt->client_address))
1495                                goto out_nomem;
1496                        break;
1497                case Opt_mounthost:
1498                        if (nfs_get_option_str(args,
1499                                               &mnt->mount_server.hostname))
1500                                goto out_nomem;
1501                        break;
1502                case Opt_mountaddr:
1503                        string = match_strdup(args);
1504                        if (string == NULL)
1505                                goto out_nomem;
1506                        mnt->mount_server.addrlen =
1507                                rpc_pton(mnt->net, string, strlen(string),
1508                                        (struct sockaddr *)
1509                                        &mnt->mount_server.address,
1510                                        sizeof(mnt->mount_server.address));
1511                        kfree(string);
1512                        if (mnt->mount_server.addrlen == 0)
1513                                goto out_invalid_address;
1514                        break;
1515                case Opt_lookupcache:
1516                        string = match_strdup(args);
1517                        if (string == NULL)
1518                                goto out_nomem;
1519                        token = match_token(string,
1520                                        nfs_lookupcache_tokens, args);
1521                        kfree(string);
1522                        switch (token) {
1523                                case Opt_lookupcache_all:
1524                                        mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1525                                        break;
1526                                case Opt_lookupcache_positive:
1527                                        mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1528                                        mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1529                                        break;
1530                                case Opt_lookupcache_none:
1531                                        mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1532                                        break;
1533                                default:
1534                                        dfprintk(MOUNT, "NFS:   invalid "
1535                                                        "lookupcache argument\n");
1536                                        return 0;
1537                        };
1538                        break;
1539                case Opt_fscache_uniq:
1540                        if (nfs_get_option_str(args, &mnt->fscache_uniq))
1541                                goto out_nomem;
1542                        mnt->options |= NFS_OPTION_FSCACHE;
1543                        break;
1544                case Opt_local_lock:
1545                        string = match_strdup(args);
1546                        if (string == NULL)
1547                                goto out_nomem;
1548                        token = match_token(string, nfs_local_lock_tokens,
1549                                        args);
1550                        kfree(string);
1551                        switch (token) {
1552                        case Opt_local_lock_all:
1553                                mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1554                                               NFS_MOUNT_LOCAL_FCNTL);
1555                                break;
1556                        case Opt_local_lock_flock:
1557                                mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1558                                break;
1559                        case Opt_local_lock_posix:
1560                                mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1561                                break;
1562                        case Opt_local_lock_none:
1563                                mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1564                                                NFS_MOUNT_LOCAL_FCNTL);
1565                                break;
1566                        default:
1567                                dfprintk(MOUNT, "NFS:   invalid "
1568                                                "local_lock argument\n");
1569                                return 0;
1570                        };
1571                        break;
1572
1573                /*
1574                 * Special options
1575                 */
1576                case Opt_sloppy:
1577                        sloppy = 1;
1578                        dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1579                        break;
1580                case Opt_userspace:
1581                case Opt_deprecated:
1582                        dfprintk(MOUNT, "NFS:   ignoring mount option "
1583                                        "'%s'\n", p);
1584                        break;
1585
1586                default:
1587                        invalid_option = 1;
1588                        dfprintk(MOUNT, "NFS:   unrecognized mount option "
1589                                        "'%s'\n", p);
1590                }
1591        }
1592
1593        if (!sloppy && invalid_option)
1594                return 0;
1595
1596        if (mnt->minorversion && mnt->version != 4)
1597                goto out_minorversion_mismatch;
1598
1599        if (mnt->options & NFS_OPTION_MIGRATION &&
1600            mnt->version != 4 && mnt->minorversion != 0)
1601                goto out_migration_misuse;
1602
1603        /*
1604         * verify that any proto=/mountproto= options match the address
1605         * families in the addr=/mountaddr= options.
1606         */
1607        if (protofamily != AF_UNSPEC &&
1608            protofamily != mnt->nfs_server.address.ss_family)
1609                goto out_proto_mismatch;
1610
1611        if (mountfamily != AF_UNSPEC) {
1612                if (mnt->mount_server.addrlen) {
1613                        if (mountfamily != mnt->mount_server.address.ss_family)
1614                                goto out_mountproto_mismatch;
1615                } else {
1616                        if (mountfamily != mnt->nfs_server.address.ss_family)
1617                                goto out_mountproto_mismatch;
1618                }
1619        }
1620
1621        return 1;
1622
1623out_mountproto_mismatch:
1624        printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1625                         "option\n");
1626        return 0;
1627out_proto_mismatch:
1628        printk(KERN_INFO "NFS: server address does not match proto= option\n");
1629        return 0;
1630out_invalid_address:
1631        printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1632        return 0;
1633out_invalid_value:
1634        printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1635        return 0;
1636out_minorversion_mismatch:
1637        printk(KERN_INFO "NFS: mount option vers=%u does not support "
1638                         "minorversion=%u\n", mnt->version, mnt->minorversion);
1639        return 0;
1640out_migration_misuse:
1641        printk(KERN_INFO
1642                "NFS: 'migration' not supported for this NFS version\n");
1643        return 0;
1644out_nomem:
1645        printk(KERN_INFO "NFS: not enough memory to parse option\n");
1646        return 0;
1647out_security_failure:
1648        free_secdata(secdata);
1649        printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1650        return 0;
1651}
1652
1653/*
1654 * Match the requested auth flavors with the list returned by
1655 * the server.  Returns zero and sets the mount's authentication
1656 * flavor on success; returns -EACCES if server does not support
1657 * the requested flavor.
1658 */
1659static int nfs_walk_authlist(struct nfs_parsed_mount_data *args,
1660                             struct nfs_mount_request *request)
1661{
1662        unsigned int i, j, server_authlist_len = *(request->auth_flav_len);
1663
1664        /*
1665         * Certain releases of Linux's mountd return an empty
1666         * flavor list.  To prevent behavioral regression with
1667         * these servers (ie. rejecting mounts that used to
1668         * succeed), revert to pre-2.6.32 behavior (no checking)
1669         * if the returned flavor list is empty.
1670         */
1671        if (server_authlist_len == 0)
1672                return 0;
1673
1674        /*
1675         * We avoid sophisticated negotiating here, as there are
1676         * plenty of cases where we can get it wrong, providing
1677         * either too little or too much security.
1678         *
1679         * RFC 2623, section 2.7 suggests we SHOULD prefer the
1680         * flavor listed first.  However, some servers list
1681         * AUTH_NULL first.  Our caller plants AUTH_SYS, the
1682         * preferred default, in args->auth_flavors[0] if user
1683         * didn't specify sec= mount option.
1684         */
1685        for (i = 0; i < args->auth_flavor_len; i++)
1686                for (j = 0; j < server_authlist_len; j++)
1687                        if (args->auth_flavors[i] == request->auth_flavs[j]) {
1688                                dfprintk(MOUNT, "NFS: using auth flavor %d\n",
1689                                        request->auth_flavs[j]);
1690                                args->auth_flavors[0] = request->auth_flavs[j];
1691                                return 0;
1692                        }
1693
1694        dfprintk(MOUNT, "NFS: server does not support requested auth flavor\n");
1695        nfs_umount(request);
1696        return -EACCES;
1697}
1698
1699/*
1700 * Use the remote server's MOUNT service to request the NFS file handle
1701 * corresponding to the provided path.
1702 */
1703static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1704                             struct nfs_fh *root_fh)
1705{
1706        rpc_authflavor_t server_authlist[NFS_MAX_SECFLAVORS];
1707        unsigned int server_authlist_len = ARRAY_SIZE(server_authlist);
1708        struct nfs_mount_request request = {
1709                .sap            = (struct sockaddr *)
1710                                                &args->mount_server.address,
1711                .dirpath        = args->nfs_server.export_path,
1712                .protocol       = args->mount_server.protocol,
1713                .fh             = root_fh,
1714                .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1715                .auth_flav_len  = &server_authlist_len,
1716                .auth_flavs     = server_authlist,
1717                .net            = args->net,
1718        };
1719        int status;
1720
1721        if (args->mount_server.version == 0) {
1722                switch (args->version) {
1723                        default:
1724                                args->mount_server.version = NFS_MNT3_VERSION;
1725                                break;
1726                        case 2:
1727                                args->mount_server.version = NFS_MNT_VERSION;
1728                }
1729        }
1730        request.version = args->mount_server.version;
1731
1732        if (args->mount_server.hostname)
1733                request.hostname = args->mount_server.hostname;
1734        else
1735                request.hostname = args->nfs_server.hostname;
1736
1737        /*
1738         * Construct the mount server's address.
1739         */
1740        if (args->mount_server.address.ss_family == AF_UNSPEC) {
1741                memcpy(request.sap, &args->nfs_server.address,
1742                       args->nfs_server.addrlen);
1743                args->mount_server.addrlen = args->nfs_server.addrlen;
1744        }
1745        request.salen = args->mount_server.addrlen;
1746        nfs_set_port(request.sap, &args->mount_server.port, 0);
1747
1748        /*
1749         * Now ask the mount server to map our export path
1750         * to a file handle.
1751         */
1752        status = nfs_mount(&request);
1753        if (status != 0) {
1754                dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1755                                request.hostname, status);
1756                return status;
1757        }
1758
1759        /*
1760         * MNTv1 (NFSv2) does not support auth flavor negotiation.
1761         */
1762        if (args->mount_server.version != NFS_MNT3_VERSION)
1763                return 0;
1764        return nfs_walk_authlist(args, &request);
1765}
1766
1767struct dentry *nfs_try_mount(int flags, const char *dev_name,
1768                             struct nfs_mount_info *mount_info,
1769                             struct nfs_subversion *nfs_mod)
1770{
1771        int status;
1772        struct nfs_server *server;
1773
1774        if (mount_info->parsed->need_mount) {
1775                status = nfs_request_mount(mount_info->parsed, mount_info->mntfh);
1776                if (status)
1777                        return ERR_PTR(status);
1778        }
1779
1780        /* Get a volume representation */
1781        server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1782        if (IS_ERR(server))
1783                return ERR_CAST(server);
1784
1785        return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1786}
1787EXPORT_SYMBOL_GPL(nfs_try_mount);
1788
1789/*
1790 * Split "dev_name" into "hostname:export_path".
1791 *
1792 * The leftmost colon demarks the split between the server's hostname
1793 * and the export path.  If the hostname starts with a left square
1794 * bracket, then it may contain colons.
1795 *
1796 * Note: caller frees hostname and export path, even on error.
1797 */
1798static int nfs_parse_devname(const char *dev_name,
1799                             char **hostname, size_t maxnamlen,
1800                             char **export_path, size_t maxpathlen)
1801{
1802        size_t len;
1803        char *end;
1804
1805        /* Is the host name protected with square brakcets? */
1806        if (*dev_name == '[') {
1807                end = strchr(++dev_name, ']');
1808                if (end == NULL || end[1] != ':')
1809                        goto out_bad_devname;
1810
1811                len = end - dev_name;
1812                end++;
1813        } else {
1814                char *comma;
1815
1816                end = strchr(dev_name, ':');
1817                if (end == NULL)
1818                        goto out_bad_devname;
1819                len = end - dev_name;
1820
1821                /* kill possible hostname list: not supported */
1822                comma = strchr(dev_name, ',');
1823                if (comma != NULL && comma < end)
1824                        *comma = 0;
1825        }
1826
1827        if (len > maxnamlen)
1828                goto out_hostname;
1829
1830        /* N.B. caller will free nfs_server.hostname in all cases */
1831        *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1832        if (*hostname == NULL)
1833                goto out_nomem;
1834        len = strlen(++end);
1835        if (len > maxpathlen)
1836                goto out_path;
1837        *export_path = kstrndup(end, len, GFP_KERNEL);
1838        if (!*export_path)
1839                goto out_nomem;
1840
1841        dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1842        return 0;
1843
1844out_bad_devname:
1845        dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1846        return -EINVAL;
1847
1848out_nomem:
1849        dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1850        return -ENOMEM;
1851
1852out_hostname:
1853        dfprintk(MOUNT, "NFS: server hostname too long\n");
1854        return -ENAMETOOLONG;
1855
1856out_path:
1857        dfprintk(MOUNT, "NFS: export pathname too long\n");
1858        return -ENAMETOOLONG;
1859}
1860
1861/*
1862 * Validate the NFS2/NFS3 mount data
1863 * - fills in the mount root filehandle
1864 *
1865 * For option strings, user space handles the following behaviors:
1866 *
1867 * + DNS: mapping server host name to IP address ("addr=" option)
1868 *
1869 * + failure mode: how to behave if a mount request can't be handled
1870 *   immediately ("fg/bg" option)
1871 *
1872 * + retry: how often to retry a mount request ("retry=" option)
1873 *
1874 * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1875 *   mountproto=tcp after mountproto=udp, and so on
1876 */
1877static int nfs23_validate_mount_data(void *options,
1878                                     struct nfs_parsed_mount_data *args,
1879                                     struct nfs_fh *mntfh,
1880                                     const char *dev_name)
1881{
1882        struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1883        struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1884
1885        if (data == NULL)
1886                goto out_no_data;
1887
1888        args->version = NFS_DEFAULT_VERSION;
1889        switch (data->version) {
1890        case 1:
1891                data->namlen = 0;
1892        case 2:
1893                data->bsize = 0;
1894        case 3:
1895                if (data->flags & NFS_MOUNT_VER3)
1896                        goto out_no_v3;
1897                data->root.size = NFS2_FHSIZE;
1898                memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1899        case 4:
1900                if (data->flags & NFS_MOUNT_SECFLAVOUR)
1901                        goto out_no_sec;
1902        case 5:
1903                memset(data->context, 0, sizeof(data->context));
1904        case 6:
1905                if (data->flags & NFS_MOUNT_VER3) {
1906                        if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1907                                goto out_invalid_fh;
1908                        mntfh->size = data->root.size;
1909                        args->version = 3;
1910                } else {
1911                        mntfh->size = NFS2_FHSIZE;
1912                        args->version = 2;
1913                }
1914
1915
1916                memcpy(mntfh->data, data->root.data, mntfh->size);
1917                if (mntfh->size < sizeof(mntfh->data))
1918                        memset(mntfh->data + mntfh->size, 0,
1919                               sizeof(mntfh->data) - mntfh->size);
1920
1921                /*
1922                 * Translate to nfs_parsed_mount_data, which nfs_fill_super
1923                 * can deal with.
1924                 */
1925                args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
1926                args->flags             |= NFS_MOUNT_LEGACY_INTERFACE;
1927                args->rsize             = data->rsize;
1928                args->wsize             = data->wsize;
1929                args->timeo             = data->timeo;
1930                args->retrans           = data->retrans;
1931                args->acregmin          = data->acregmin;
1932                args->acregmax          = data->acregmax;
1933                args->acdirmin          = data->acdirmin;
1934                args->acdirmax          = data->acdirmax;
1935                args->need_mount        = false;
1936
1937                memcpy(sap, &data->addr, sizeof(data->addr));
1938                args->nfs_server.addrlen = sizeof(data->addr);
1939                args->nfs_server.port = ntohs(data->addr.sin_port);
1940                if (!nfs_verify_server_address(sap))
1941                        goto out_no_address;
1942
1943                if (!(data->flags & NFS_MOUNT_TCP))
1944                        args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1945                /* N.B. caller will free nfs_server.hostname in all cases */
1946                args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1947                args->namlen            = data->namlen;
1948                args->bsize             = data->bsize;
1949
1950                if (data->flags & NFS_MOUNT_SECFLAVOUR)
1951                        args->auth_flavors[0] = data->pseudoflavor;
1952                if (!args->nfs_server.hostname)
1953                        goto out_nomem;
1954
1955                if (!(data->flags & NFS_MOUNT_NONLM))
1956                        args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1957                                         NFS_MOUNT_LOCAL_FCNTL);
1958                else
1959                        args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1960                                        NFS_MOUNT_LOCAL_FCNTL);
1961                /*
1962                 * The legacy version 6 binary mount data from userspace has a
1963                 * field used only to transport selinux information into the
1964                 * the kernel.  To continue to support that functionality we
1965                 * have a touch of selinux knowledge here in the NFS code. The
1966                 * userspace code converted context=blah to just blah so we are
1967                 * converting back to the full string selinux understands.
1968                 */
1969                if (data->context[0]){
1970#ifdef CONFIG_SECURITY_SELINUX
1971                        int rc;
1972                        char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1973                        if (!opts_str)
1974                                return -ENOMEM;
1975                        strcpy(opts_str, "context=");
1976                        data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1977                        strcat(opts_str, &data->context[0]);
1978                        rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1979                        kfree(opts_str);
1980                        if (rc)
1981                                return rc;
1982#else
1983                        return -EINVAL;
1984#endif
1985                }
1986
1987                break;
1988        default:
1989                return NFS_TEXT_DATA;
1990        }
1991
1992#if !IS_ENABLED(CONFIG_NFS_V3)
1993        if (args->version == 3)
1994                goto out_v3_not_compiled;
1995#endif /* !CONFIG_NFS_V3 */
1996
1997        return 0;
1998
1999out_no_data:
2000        dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2001        return -EINVAL;
2002
2003out_no_v3:
2004        dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2005                 data->version);
2006        return -EINVAL;
2007
2008out_no_sec:
2009        dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2010        return -EINVAL;
2011
2012#if !IS_ENABLED(CONFIG_NFS_V3)
2013out_v3_not_compiled:
2014        dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
2015        return -EPROTONOSUPPORT;
2016#endif /* !CONFIG_NFS_V3 */
2017
2018out_nomem:
2019        dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2020        return -ENOMEM;
2021
2022out_no_address:
2023        dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2024        return -EINVAL;
2025
2026out_invalid_fh:
2027        dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2028        return -EINVAL;
2029}
2030
2031#if IS_ENABLED(CONFIG_NFS_V4)
2032static int nfs_validate_mount_data(struct file_system_type *fs_type,
2033                                   void *options,
2034                                   struct nfs_parsed_mount_data *args,
2035                                   struct nfs_fh *mntfh,
2036                                   const char *dev_name)
2037{
2038        if (fs_type == &nfs_fs_type)
2039                return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2040        return nfs4_validate_mount_data(options, args, dev_name);
2041}
2042#else
2043static int nfs_validate_mount_data(struct file_system_type *fs_type,
2044                                   void *options,
2045                                   struct nfs_parsed_mount_data *args,
2046                                   struct nfs_fh *mntfh,
2047                                   const char *dev_name)
2048{
2049        return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2050}
2051#endif
2052
2053static int nfs_validate_text_mount_data(void *options,
2054                                        struct nfs_parsed_mount_data *args,
2055                                        const char *dev_name)
2056{
2057        int port = 0;
2058        int max_namelen = PAGE_SIZE;
2059        int max_pathlen = NFS_MAXPATHLEN;
2060        struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2061
2062        if (nfs_parse_mount_options((char *)options, args) == 0)
2063                return -EINVAL;
2064
2065        if (!nfs_verify_server_address(sap))
2066                goto out_no_address;
2067
2068        if (args->version == 4) {
2069#if IS_ENABLED(CONFIG_NFS_V4)
2070                port = NFS_PORT;
2071                max_namelen = NFS4_MAXNAMLEN;
2072                max_pathlen = NFS4_MAXPATHLEN;
2073                nfs_validate_transport_protocol(args);
2074                nfs4_validate_mount_flags(args);
2075#else
2076                goto out_v4_not_compiled;
2077#endif /* CONFIG_NFS_V4 */
2078        } else
2079                nfs_set_mount_transport_protocol(args);
2080
2081        nfs_set_port(sap, &args->nfs_server.port, port);
2082
2083        if (args->auth_flavor_len > 1)
2084                goto out_bad_auth;
2085
2086        return nfs_parse_devname(dev_name,
2087                                   &args->nfs_server.hostname,
2088                                   max_namelen,
2089                                   &args->nfs_server.export_path,
2090                                   max_pathlen);
2091
2092#if !IS_ENABLED(CONFIG_NFS_V4)
2093out_v4_not_compiled:
2094        dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2095        return -EPROTONOSUPPORT;
2096#endif /* !CONFIG_NFS_V4 */
2097
2098out_no_address:
2099        dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2100        return -EINVAL;
2101
2102out_bad_auth:
2103        dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
2104        return -EINVAL;
2105}
2106
2107static int
2108nfs_compare_remount_data(struct nfs_server *nfss,
2109                         struct nfs_parsed_mount_data *data)
2110{
2111        if (data->flags != nfss->flags ||
2112            data->rsize != nfss->rsize ||
2113            data->wsize != nfss->wsize ||
2114            data->retrans != nfss->client->cl_timeout->to_retries ||
2115            data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2116            data->acregmin != nfss->acregmin / HZ ||
2117            data->acregmax != nfss->acregmax / HZ ||
2118            data->acdirmin != nfss->acdirmin / HZ ||
2119            data->acdirmax != nfss->acdirmax / HZ ||
2120            data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2121            data->nfs_server.port != nfss->port ||
2122            data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2123            !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2124                          (struct sockaddr *)&nfss->nfs_client->cl_addr))
2125                return -EINVAL;
2126
2127        return 0;
2128}
2129
2130int
2131nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2132{
2133        int error;
2134        struct nfs_server *nfss = sb->s_fs_info;
2135        struct nfs_parsed_mount_data *data;
2136        struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2137        struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2138        u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2139
2140        /*
2141         * Userspace mount programs that send binary options generally send
2142         * them populated with default values. We have no way to know which
2143         * ones were explicitly specified. Fall back to legacy behavior and
2144         * just return success.
2145         */
2146        if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2147            (nfsvers <= 3 && (!options || (options->version >= 1 &&
2148                                           options->version <= 6))))
2149                return 0;
2150
2151        data = kzalloc(sizeof(*data), GFP_KERNEL);
2152        if (data == NULL)
2153                return -ENOMEM;
2154
2155        /* fill out struct with values from existing mount */
2156        data->flags = nfss->flags;
2157        data->rsize = nfss->rsize;
2158        data->wsize = nfss->wsize;
2159        data->retrans = nfss->client->cl_timeout->to_retries;
2160        data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2161        data->acregmin = nfss->acregmin / HZ;
2162        data->acregmax = nfss->acregmax / HZ;
2163        data->acdirmin = nfss->acdirmin / HZ;
2164        data->acdirmax = nfss->acdirmax / HZ;
2165        data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2166        data->nfs_server.port = nfss->port;
2167        data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2168        memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2169                data->nfs_server.addrlen);
2170
2171        /* overwrite those values with any that were specified */
2172        error = nfs_parse_mount_options((char *)options, data);
2173        if (error < 0)
2174                goto out;
2175
2176        /*
2177         * noac is a special case. It implies -o sync, but that's not
2178         * necessarily reflected in the mtab options. do_remount_sb
2179         * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2180         * remount options, so we have to explicitly reset it.
2181         */
2182        if (data->flags & NFS_MOUNT_NOAC)
2183                *flags |= MS_SYNCHRONOUS;
2184
2185        /* compare new mount options with old ones */
2186        error = nfs_compare_remount_data(nfss, data);
2187out:
2188        kfree(data);
2189        return error;
2190}
2191EXPORT_SYMBOL_GPL(nfs_remount);
2192
2193/*
2194 * Initialise the common bits of the superblock
2195 */
2196inline void nfs_initialise_sb(struct super_block *sb)
2197{
2198        struct nfs_server *server = NFS_SB(sb);
2199
2200        sb->s_magic = NFS_SUPER_MAGIC;
2201
2202        /* We probably want something more informative here */
2203        snprintf(sb->s_id, sizeof(sb->s_id),
2204                 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2205
2206        if (sb->s_blocksize == 0)
2207                sb->s_blocksize = nfs_block_bits(server->wsize,
2208                                                 &sb->s_blocksize_bits);
2209
2210        sb->s_bdi = &server->backing_dev_info;
2211
2212        nfs_super_set_maxbytes(sb, server->maxfilesize);
2213}
2214
2215/*
2216 * Finish setting up an NFS2/3 superblock
2217 */
2218void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2219{
2220        struct nfs_parsed_mount_data *data = mount_info->parsed;
2221        struct nfs_server *server = NFS_SB(sb);
2222
2223        sb->s_blocksize_bits = 0;
2224        sb->s_blocksize = 0;
2225        sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2226        sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2227        if (data && data->bsize)
2228                sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2229
2230        if (server->nfs_client->rpc_ops->version != 2) {
2231                /* The VFS shouldn't apply the umask to mode bits. We will do
2232                 * so ourselves when necessary.
2233                 */
2234                sb->s_flags |= MS_POSIXACL;
2235                sb->s_time_gran = 1;
2236        }
2237
2238        nfs_initialise_sb(sb);
2239}
2240EXPORT_SYMBOL_GPL(nfs_fill_super);
2241
2242/*
2243 * Finish setting up a cloned NFS2/3/4 superblock
2244 */
2245void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2246{
2247        const struct super_block *old_sb = mount_info->cloned->sb;
2248        struct nfs_server *server = NFS_SB(sb);
2249
2250        sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2251        sb->s_blocksize = old_sb->s_blocksize;
2252        sb->s_maxbytes = old_sb->s_maxbytes;
2253        sb->s_xattr = old_sb->s_xattr;
2254        sb->s_op = old_sb->s_op;
2255        sb->s_time_gran = 1;
2256
2257        if (server->nfs_client->rpc_ops->version != 2) {
2258                /* The VFS shouldn't apply the umask to mode bits. We will do
2259                 * so ourselves when necessary.
2260                 */
2261                sb->s_flags |= MS_POSIXACL;
2262        }
2263
2264        nfs_initialise_sb(sb);
2265}
2266
2267static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2268{
2269        const struct nfs_server *a = s->s_fs_info;
2270        const struct rpc_clnt *clnt_a = a->client;
2271        const struct rpc_clnt *clnt_b = b->client;
2272
2273        if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2274                goto Ebusy;
2275        if (a->nfs_client != b->nfs_client)
2276                goto Ebusy;
2277        if (a->flags != b->flags)
2278                goto Ebusy;
2279        if (a->wsize != b->wsize)
2280                goto Ebusy;
2281        if (a->rsize != b->rsize)
2282                goto Ebusy;
2283        if (a->acregmin != b->acregmin)
2284                goto Ebusy;
2285        if (a->acregmax != b->acregmax)
2286                goto Ebusy;
2287        if (a->acdirmin != b->acdirmin)
2288                goto Ebusy;
2289        if (a->acdirmax != b->acdirmax)
2290                goto Ebusy;
2291        if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2292                goto Ebusy;
2293        return 1;
2294Ebusy:
2295        return 0;
2296}
2297
2298struct nfs_sb_mountdata {
2299        struct nfs_server *server;
2300        int mntflags;
2301};
2302
2303static int nfs_set_super(struct super_block *s, void *data)
2304{
2305        struct nfs_sb_mountdata *sb_mntdata = data;
2306        struct nfs_server *server = sb_mntdata->server;
2307        int ret;
2308
2309        s->s_flags = sb_mntdata->mntflags;
2310        s->s_fs_info = server;
2311        s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2312        ret = set_anon_super(s, server);
2313        if (ret == 0)
2314                server->s_dev = s->s_dev;
2315        return ret;
2316}
2317
2318static int nfs_compare_super_address(struct nfs_server *server1,
2319                                     struct nfs_server *server2)
2320{
2321        struct sockaddr *sap1, *sap2;
2322
2323        sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2324        sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2325
2326        if (sap1->sa_family != sap2->sa_family)
2327                return 0;
2328
2329        switch (sap1->sa_family) {
2330        case AF_INET: {
2331                struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2332                struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2333                if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2334                        return 0;
2335                if (sin1->sin_port != sin2->sin_port)
2336                        return 0;
2337                break;
2338        }
2339        case AF_INET6: {
2340                struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2341                struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2342                if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2343                        return 0;
2344                if (sin1->sin6_port != sin2->sin6_port)
2345                        return 0;
2346                break;
2347        }
2348        default:
2349                return 0;
2350        }
2351
2352        return 1;
2353}
2354
2355static int nfs_compare_super(struct super_block *sb, void *data)
2356{
2357        struct nfs_sb_mountdata *sb_mntdata = data;
2358        struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2359        int mntflags = sb_mntdata->mntflags;
2360
2361        if (!nfs_compare_super_address(old, server))
2362                return 0;
2363        /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2364        if (old->flags & NFS_MOUNT_UNSHARED)
2365                return 0;
2366        if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2367                return 0;
2368        return nfs_compare_mount_options(sb, server, mntflags);
2369}
2370
2371#ifdef CONFIG_NFS_FSCACHE
2372static void nfs_get_cache_cookie(struct super_block *sb,
2373                                 struct nfs_parsed_mount_data *parsed,
2374                                 struct nfs_clone_mount *cloned)
2375{
2376        char *uniq = NULL;
2377        int ulen = 0;
2378
2379        if (parsed && parsed->fscache_uniq) {
2380                uniq = parsed->fscache_uniq;
2381                ulen = strlen(parsed->fscache_uniq);
2382        } else if (cloned) {
2383                struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2384                if (mnt_s->fscache_key) {
2385                        uniq = mnt_s->fscache_key->key.uniquifier;
2386                        ulen = mnt_s->fscache_key->key.uniq_len;
2387                };
2388        }
2389
2390        nfs_fscache_get_super_cookie(sb, uniq, ulen);
2391}
2392#else
2393static void nfs_get_cache_cookie(struct super_block *sb,
2394                                 struct nfs_parsed_mount_data *parsed,
2395                                 struct nfs_clone_mount *cloned)
2396{
2397}
2398#endif
2399
2400static int nfs_bdi_register(struct nfs_server *server)
2401{
2402        return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2403}
2404
2405int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2406                        struct nfs_mount_info *mount_info)
2407{
2408        return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts);
2409}
2410EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2411
2412int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2413                          struct nfs_mount_info *mount_info)
2414{
2415        /* clone any lsm security options from the parent to the new sb */
2416        security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2417        if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2418                return -ESTALE;
2419        return 0;
2420}
2421EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2422
2423struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2424                                   int flags, const char *dev_name,
2425                                   struct nfs_mount_info *mount_info,
2426                                   struct nfs_subversion *nfs_mod)
2427{
2428        struct super_block *s;
2429        struct dentry *mntroot = ERR_PTR(-ENOMEM);
2430        int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2431        struct nfs_sb_mountdata sb_mntdata = {
2432                .mntflags = flags,
2433                .server = server,
2434        };
2435        int error;
2436
2437        if (server->flags & NFS_MOUNT_UNSHARED)
2438                compare_super = NULL;
2439
2440        /* -o noac implies -o sync */
2441        if (server->flags & NFS_MOUNT_NOAC)
2442                sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2443
2444        /* Get a superblock - note that we may end up sharing one that already exists */
2445        s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2446        if (IS_ERR(s)) {
2447                mntroot = ERR_CAST(s);
2448                goto out_err_nosb;
2449        }
2450
2451        if (s->s_fs_info != server) {
2452                nfs_free_server(server);
2453                server = NULL;
2454        } else {
2455                error = nfs_bdi_register(server);
2456                if (error) {
2457                        mntroot = ERR_PTR(error);
2458                        goto error_splat_bdi;
2459                }
2460        }
2461
2462        if (!s->s_root) {
2463                /* initial superblock/root creation */
2464                mount_info->fill_super(s, mount_info);
2465                nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2466        }
2467
2468        mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2469        if (IS_ERR(mntroot))
2470                goto error_splat_super;
2471
2472        error = mount_info->set_security(s, mntroot, mount_info);
2473        if (error)
2474                goto error_splat_root;
2475
2476        s->s_flags |= MS_ACTIVE;
2477
2478out:
2479        return mntroot;
2480
2481out_err_nosb:
2482        nfs_free_server(server);
2483        goto out;
2484
2485error_splat_root:
2486        dput(mntroot);
2487        mntroot = ERR_PTR(error);
2488error_splat_super:
2489        if (server && !s->s_root)
2490                bdi_unregister(&server->backing_dev_info);
2491error_splat_bdi:
2492        deactivate_locked_super(s);
2493        goto out;
2494}
2495EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2496
2497struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2498        int flags, const char *dev_name, void *raw_data)
2499{
2500        struct nfs_mount_info mount_info = {
2501                .fill_super = nfs_fill_super,
2502                .set_security = nfs_set_sb_security,
2503        };
2504        struct dentry *mntroot = ERR_PTR(-ENOMEM);
2505        struct nfs_subversion *nfs_mod;
2506        int error;
2507
2508        mount_info.parsed = nfs_alloc_parsed_mount_data();
2509        mount_info.mntfh = nfs_alloc_fhandle();
2510        if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2511                goto out;
2512
2513        /* Validate the mount data */
2514        error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2515        if (error == NFS_TEXT_DATA)
2516                error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2517        if (error < 0) {
2518                mntroot = ERR_PTR(error);
2519                goto out;
2520        }
2521
2522        nfs_mod = get_nfs_version(mount_info.parsed->version);
2523        if (IS_ERR(nfs_mod)) {
2524                mntroot = ERR_CAST(nfs_mod);
2525                goto out;
2526        }
2527
2528        mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2529
2530        put_nfs_version(nfs_mod);
2531out:
2532        nfs_free_parsed_mount_data(mount_info.parsed);
2533        nfs_free_fhandle(mount_info.mntfh);
2534        return mntroot;
2535}
2536EXPORT_SYMBOL_GPL(nfs_fs_mount);
2537
2538/*
2539 * Ensure that we unregister the bdi before kill_anon_super
2540 * releases the device name
2541 */
2542void nfs_put_super(struct super_block *s)
2543{
2544        struct nfs_server *server = NFS_SB(s);
2545
2546        bdi_unregister(&server->backing_dev_info);
2547}
2548EXPORT_SYMBOL_GPL(nfs_put_super);
2549
2550/*
2551 * Destroy an NFS2/3 superblock
2552 */
2553void nfs_kill_super(struct super_block *s)
2554{
2555        struct nfs_server *server = NFS_SB(s);
2556
2557        kill_anon_super(s);
2558        nfs_fscache_release_super_cookie(s);
2559        nfs_free_server(server);
2560}
2561EXPORT_SYMBOL_GPL(nfs_kill_super);
2562
2563/*
2564 * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2565 */
2566static struct dentry *
2567nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2568                const char *dev_name, void *raw_data)
2569{
2570        struct nfs_clone_mount *data = raw_data;
2571        struct nfs_mount_info mount_info = {
2572                .fill_super = nfs_clone_super,
2573                .set_security = nfs_clone_sb_security,
2574                .cloned = data,
2575        };
2576        struct nfs_server *server;
2577        struct dentry *mntroot = ERR_PTR(-ENOMEM);
2578        struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2579        int error;
2580
2581        dprintk("--> nfs_xdev_mount_common()\n");
2582
2583        mount_info.mntfh = mount_info.cloned->fh;
2584
2585        /* create a new volume representation */
2586        server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2587        if (IS_ERR(server)) {
2588                error = PTR_ERR(server);
2589                goto out_err;
2590        }
2591
2592        mntroot = nfs_fs_mount_common(server, flags, dev_name, &mount_info, nfs_mod);
2593        dprintk("<-- nfs_xdev_mount_common() = 0\n");
2594out:
2595        return mntroot;
2596
2597out_err:
2598        dprintk("<-- nfs_xdev_mount_common() = %d [error]\n", error);
2599        goto out;
2600}
2601
2602#if IS_ENABLED(CONFIG_NFS_V4)
2603
2604static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2605{
2606        args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2607                         NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2608}
2609
2610/*
2611 * Validate NFSv4 mount options
2612 */
2613static int nfs4_validate_mount_data(void *options,
2614                                    struct nfs_parsed_mount_data *args,
2615                                    const char *dev_name)
2616{
2617        struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2618        struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2619        char *c;
2620
2621        if (data == NULL)
2622                goto out_no_data;
2623
2624        args->version = 4;
2625
2626        switch (data->version) {
2627        case 1:
2628                if (data->host_addrlen > sizeof(args->nfs_server.address))
2629                        goto out_no_address;
2630                if (data->host_addrlen == 0)
2631                        goto out_no_address;
2632                args->nfs_server.addrlen = data->host_addrlen;
2633                if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2634                        return -EFAULT;
2635                if (!nfs_verify_server_address(sap))
2636                        goto out_no_address;
2637                args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2638
2639                if (data->auth_flavourlen) {
2640                        if (data->auth_flavourlen > 1)
2641                                goto out_inval_auth;
2642                        if (copy_from_user(&args->auth_flavors[0],
2643                                           data->auth_flavours,
2644                                           sizeof(args->auth_flavors[0])))
2645                                return -EFAULT;
2646                }
2647
2648                c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2649                if (IS_ERR(c))
2650                        return PTR_ERR(c);
2651                args->nfs_server.hostname = c;
2652
2653                c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2654                if (IS_ERR(c))
2655                        return PTR_ERR(c);
2656                args->nfs_server.export_path = c;
2657                dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2658
2659                c = strndup_user(data->client_addr.data, 16);
2660                if (IS_ERR(c))
2661                        return PTR_ERR(c);
2662                args->client_address = c;
2663
2664                /*
2665                 * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2666                 * can deal with.
2667                 */
2668
2669                args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2670                args->rsize     = data->rsize;
2671                args->wsize     = data->wsize;
2672                args->timeo     = data->timeo;
2673                args->retrans   = data->retrans;
2674                args->acregmin  = data->acregmin;
2675                args->acregmax  = data->acregmax;
2676                args->acdirmin  = data->acdirmin;
2677                args->acdirmax  = data->acdirmax;
2678                args->nfs_server.protocol = data->proto;
2679                nfs_validate_transport_protocol(args);
2680
2681                break;
2682        default:
2683                return NFS_TEXT_DATA;
2684        }
2685
2686        return 0;
2687
2688out_no_data:
2689        dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2690        return -EINVAL;
2691
2692out_inval_auth:
2693        dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2694                 data->auth_flavourlen);
2695        return -EINVAL;
2696
2697out_no_address:
2698        dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2699        return -EINVAL;
2700}
2701
2702/*
2703 * NFS v4 module parameters need to stay in the
2704 * NFS client for backwards compatibility
2705 */
2706unsigned int nfs_callback_set_tcpport;
2707unsigned short nfs_callback_tcpport;
2708/* Default cache timeout is 10 minutes */
2709unsigned int nfs_idmap_cache_timeout = 600;
2710/* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2711bool nfs4_disable_idmapping = true;
2712unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2713unsigned short send_implementation_id = 1;
2714char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2715
2716EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2717EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2718EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2719EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2720EXPORT_SYMBOL_GPL(max_session_slots);
2721EXPORT_SYMBOL_GPL(send_implementation_id);
2722EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2723
2724#define NFS_CALLBACK_MAXPORTNR (65535U)
2725
2726static int param_set_portnr(const char *val, const struct kernel_param *kp)
2727{
2728        unsigned long num;
2729        int ret;
2730
2731        if (!val)
2732                return -EINVAL;
2733        ret = kstrtoul(val, 0, &num);
2734        if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2735                return -EINVAL;
2736        *((unsigned int *)kp->arg) = num;
2737        return 0;
2738}
2739static struct kernel_param_ops param_ops_portnr = {
2740        .set = param_set_portnr,
2741        .get = param_get_uint,
2742};
2743#define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2744
2745module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2746module_param(nfs_idmap_cache_timeout, int, 0644);
2747module_param(nfs4_disable_idmapping, bool, 0644);
2748module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2749                        NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2750MODULE_PARM_DESC(nfs4_disable_idmapping,
2751                "Turn off NFSv4 idmapping when using 'sec=sys'");
2752module_param(max_session_slots, ushort, 0644);
2753MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2754                "requests the client will negotiate");
2755module_param(send_implementation_id, ushort, 0644);
2756MODULE_PARM_DESC(send_implementation_id,
2757                "Send implementation ID with NFSv4.1 exchange_id");
2758MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2759MODULE_ALIAS("nfs4");
2760
2761#endif /* CONFIG_NFS_V4 */
2762
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