fs/nfs/fs_context.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * linux/fs/nfs/fs_context.c
   4  *
   5  * Copyright (C) 1992 Rick Sladkey
   6  * Conversion to new mount api Copyright (C) David Howells
   7  *
   8  * NFS mount handling.
   9  *
  10  * Split from fs/nfs/super.c by David Howells <dhowells@redhat.com>
  11  */
  12
  13 #include <linux/compat.h>
  14 #include <linux/module.h>
  15 #include <linux/fs.h>
  16 #include <linux/fs_context.h>
  17 #include <linux/fs_parser.h>
  18 #include <linux/nfs_fs.h>
  19 #include <linux/nfs_mount.h>
  20 #include <linux/nfs4_mount.h>
  21 #include "nfs.h"
  22 #include "internal.h"
  23
  24 #include "nfstrace.h"
  25
  26 #define NFSDBG_FACILITY         NFSDBG_MOUNT
  27
  28 #if IS_ENABLED(CONFIG_NFS_V3)
  29 #define NFS_DEFAULT_VERSION 3
  30 #else
  31 #define NFS_DEFAULT_VERSION 2
  32 #endif
  33
  34 #define NFS_MAX_CONNECTIONS 16
  35
  36 enum nfs_param {
  37         Opt_ac,
  38         Opt_acdirmax,
  39         Opt_acdirmin,
  40         Opt_acl,
  41         Opt_acregmax,
  42         Opt_acregmin,
  43         Opt_actimeo,
  44         Opt_addr,
  45         Opt_bg,
  46         Opt_bsize,
  47         Opt_clientaddr,
  48         Opt_cto,
  49         Opt_fg,
  50         Opt_fscache,
  51         Opt_fscache_flag,
  52         Opt_hard,
  53         Opt_intr,
  54         Opt_local_lock,
  55         Opt_lock,
  56         Opt_lookupcache,
  57         Opt_migration,
  58         Opt_minorversion,
  59         Opt_mountaddr,
  60         Opt_mounthost,
  61         Opt_mountport,
  62         Opt_mountproto,
  63         Opt_mountvers,
  64         Opt_namelen,
  65         Opt_nconnect,
  66         Opt_max_connect,
  67         Opt_port,
  68         Opt_posix,
  69         Opt_proto,
  70         Opt_rdirplus,
  71         Opt_rdma,
  72         Opt_resvport,
  73         Opt_retrans,
  74         Opt_retry,
  75         Opt_rsize,
  76         Opt_sec,
  77         Opt_sharecache,
  78         Opt_sloppy,
  79         Opt_soft,
  80         Opt_softerr,
  81         Opt_softreval,
  82         Opt_source,
  83         Opt_tcp,
  84         Opt_timeo,
  85         Opt_trunkdiscovery,
  86         Opt_udp,
  87         Opt_v,
  88         Opt_vers,
  89         Opt_wsize,
  90         Opt_write,
  91 };
  92
  93 enum {
  94         Opt_local_lock_all,
  95         Opt_local_lock_flock,
  96         Opt_local_lock_none,
  97         Opt_local_lock_posix,
  98 };
  99
 100 static const struct constant_table nfs_param_enums_local_lock[] = {
 101         { "all",                Opt_local_lock_all },
 102         { "flock",      Opt_local_lock_flock },
 103         { "posix",      Opt_local_lock_posix },
 104         { "none",               Opt_local_lock_none },
 105         {}
 106 };
 107
 108 enum {
 109         Opt_lookupcache_all,
 110         Opt_lookupcache_none,
 111         Opt_lookupcache_positive,
 112 };
 113
 114 static const struct constant_table nfs_param_enums_lookupcache[] = {
 115         { "all",                Opt_lookupcache_all },
 116         { "none",               Opt_lookupcache_none },
 117         { "pos",                Opt_lookupcache_positive },
 118         { "positive",           Opt_lookupcache_positive },
 119         {}
 120 };
 121
 122 enum {
 123         Opt_write_lazy,
 124         Opt_write_eager,
 125         Opt_write_wait,
 126 };
 127
 128 static const struct constant_table nfs_param_enums_write[] = {
 129         { "lazy",               Opt_write_lazy },
 130         { "eager",              Opt_write_eager },
 131         { "wait",               Opt_write_wait },
 132         {}
 133 };
 134
 135 static const struct fs_parameter_spec nfs_fs_parameters[] = {
 136         fsparam_flag_no("ac",           Opt_ac),
 137         fsparam_u32   ("acdirmax",      Opt_acdirmax),
 138         fsparam_u32   ("acdirmin",      Opt_acdirmin),
 139         fsparam_flag_no("acl",          Opt_acl),
 140         fsparam_u32   ("acregmax",      Opt_acregmax),
 141         fsparam_u32   ("acregmin",      Opt_acregmin),
 142         fsparam_u32   ("actimeo",       Opt_actimeo),
 143         fsparam_string("addr",          Opt_addr),
 144         fsparam_flag  ("bg",            Opt_bg),
 145         fsparam_u32   ("bsize",         Opt_bsize),
 146         fsparam_string("clientaddr",    Opt_clientaddr),
 147         fsparam_flag_no("cto",          Opt_cto),
 148         fsparam_flag  ("fg",            Opt_fg),
 149         fsparam_flag_no("fsc",          Opt_fscache_flag),
 150         fsparam_string("fsc",           Opt_fscache),
 151         fsparam_flag  ("hard",          Opt_hard),
 152         __fsparam(NULL, "intr",         Opt_intr,
 153                   fs_param_neg_with_no|fs_param_deprecated, NULL),
 154         fsparam_enum  ("local_lock",    Opt_local_lock, nfs_param_enums_local_lock),
 155         fsparam_flag_no("lock",         Opt_lock),
 156         fsparam_enum  ("lookupcache",   Opt_lookupcache, nfs_param_enums_lookupcache),
 157         fsparam_flag_no("migration",    Opt_migration),
 158         fsparam_u32   ("minorversion",  Opt_minorversion),
 159         fsparam_string("mountaddr",     Opt_mountaddr),
 160         fsparam_string("mounthost",     Opt_mounthost),
 161         fsparam_u32   ("mountport",     Opt_mountport),
 162         fsparam_string("mountproto",    Opt_mountproto),
 163         fsparam_u32   ("mountvers",     Opt_mountvers),
 164         fsparam_u32   ("namlen",        Opt_namelen),
 165         fsparam_u32   ("nconnect",      Opt_nconnect),
 166         fsparam_u32   ("max_connect",   Opt_max_connect),
 167         fsparam_string("nfsvers",       Opt_vers),
 168         fsparam_u32   ("port",          Opt_port),
 169         fsparam_flag_no("posix",        Opt_posix),
 170         fsparam_string("proto",         Opt_proto),
 171         fsparam_flag_no("rdirplus",     Opt_rdirplus),
 172         fsparam_flag  ("rdma",          Opt_rdma),
 173         fsparam_flag_no("resvport",     Opt_resvport),
 174         fsparam_u32   ("retrans",       Opt_retrans),
 175         fsparam_string("retry",         Opt_retry),
 176         fsparam_u32   ("rsize",         Opt_rsize),
 177         fsparam_string("sec",           Opt_sec),
 178         fsparam_flag_no("sharecache",   Opt_sharecache),
 179         fsparam_flag  ("sloppy",        Opt_sloppy),
 180         fsparam_flag  ("soft",          Opt_soft),
 181         fsparam_flag  ("softerr",       Opt_softerr),
 182         fsparam_flag  ("softreval",     Opt_softreval),
 183         fsparam_string("source",        Opt_source),
 184         fsparam_flag  ("tcp",           Opt_tcp),
 185         fsparam_u32   ("timeo",         Opt_timeo),
 186         fsparam_flag_no("trunkdiscovery", Opt_trunkdiscovery),
 187         fsparam_flag  ("udp",           Opt_udp),
 188         fsparam_flag  ("v2",            Opt_v),
 189         fsparam_flag  ("v3",            Opt_v),
 190         fsparam_flag  ("v4",            Opt_v),
 191         fsparam_flag  ("v4.0",          Opt_v),
 192         fsparam_flag  ("v4.1",          Opt_v),
 193         fsparam_flag  ("v4.2",          Opt_v),
 194         fsparam_string("vers",          Opt_vers),
 195         fsparam_enum  ("write",         Opt_write, nfs_param_enums_write),
 196         fsparam_u32   ("wsize",         Opt_wsize),
 197         {}
 198 };
 199
 200 enum {
 201         Opt_vers_2,
 202         Opt_vers_3,
 203         Opt_vers_4,
 204         Opt_vers_4_0,
 205         Opt_vers_4_1,
 206         Opt_vers_4_2,
 207 };
 208
 209 static const struct constant_table nfs_vers_tokens[] = {
 210         { "2",          Opt_vers_2 },
 211         { "3",          Opt_vers_3 },
 212         { "4",          Opt_vers_4 },
 213         { "4.0",        Opt_vers_4_0 },
 214         { "4.1",        Opt_vers_4_1 },
 215         { "4.2",        Opt_vers_4_2 },
 216         {}
 217 };
 218
 219 enum {
 220         Opt_xprt_rdma,
 221         Opt_xprt_rdma6,
 222         Opt_xprt_tcp,
 223         Opt_xprt_tcp6,
 224         Opt_xprt_udp,
 225         Opt_xprt_udp6,
 226         nr__Opt_xprt
 227 };
 228
 229 static const struct constant_table nfs_xprt_protocol_tokens[] = {
 230         { "rdma",       Opt_xprt_rdma },
 231         { "rdma6",      Opt_xprt_rdma6 },
 232         { "tcp",        Opt_xprt_tcp },
 233         { "tcp6",       Opt_xprt_tcp6 },
 234         { "udp",        Opt_xprt_udp },
 235         { "udp6",       Opt_xprt_udp6 },
 236         {}
 237 };
 238
 239 enum {
 240         Opt_sec_krb5,
 241         Opt_sec_krb5i,
 242         Opt_sec_krb5p,
 243         Opt_sec_lkey,
 244         Opt_sec_lkeyi,
 245         Opt_sec_lkeyp,
 246         Opt_sec_none,
 247         Opt_sec_spkm,
 248         Opt_sec_spkmi,
 249         Opt_sec_spkmp,
 250         Opt_sec_sys,
 251         nr__Opt_sec
 252 };
 253
 254 static const struct constant_table nfs_secflavor_tokens[] = {
 255         { "krb5",       Opt_sec_krb5 },
 256         { "krb5i",      Opt_sec_krb5i },
 257         { "krb5p",      Opt_sec_krb5p },
 258         { "lkey",       Opt_sec_lkey },
 259         { "lkeyi",      Opt_sec_lkeyi },
 260         { "lkeyp",      Opt_sec_lkeyp },
 261         { "none",       Opt_sec_none },
 262         { "null",       Opt_sec_none },
 263         { "spkm3",      Opt_sec_spkm },
 264         { "spkm3i",     Opt_sec_spkmi },
 265         { "spkm3p",     Opt_sec_spkmp },
 266         { "sys",        Opt_sec_sys },
 267         {}
 268 };
 269
 270 /*
 271  * Sanity-check a server address provided by the mount command.
 272  *
 273  * Address family must be initialized, and address must not be
 274  * the ANY address for that family.
 275  */
 276 static int nfs_verify_server_address(struct sockaddr_storage *addr)
 277 {
 278         switch (addr->ss_family) {
 279         case AF_INET: {
 280                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
 281                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
 282         }
 283         case AF_INET6: {
 284                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
 285                 return !ipv6_addr_any(sa);
 286         }
 287         }
 288
 289         return 0;
 290 }
 291
 292 #ifdef CONFIG_NFS_DISABLE_UDP_SUPPORT
 293 static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
 294 {
 295         return true;
 296 }
 297 #else
 298 static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
 299 {
 300         if (ctx->version == 4)
 301                 return true;
 302         return false;
 303 }
 304 #endif
 305
 306 /*
 307  * Sanity check the NFS transport protocol.
 308  */
 309 static int nfs_validate_transport_protocol(struct fs_context *fc,
 310                                            struct nfs_fs_context *ctx)
 311 {
 312         switch (ctx->nfs_server.protocol) {
 313         case XPRT_TRANSPORT_UDP:
 314                 if (nfs_server_transport_udp_invalid(ctx))
 315                         goto out_invalid_transport_udp;
 316                 break;
 317         case XPRT_TRANSPORT_TCP:
 318         case XPRT_TRANSPORT_RDMA:
 319                 break;
 320         default:
 321                 ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 322         }
 323         return 0;
 324 out_invalid_transport_udp:
 325         return nfs_invalf(fc, "NFS: Unsupported transport protocol udp");
 326 }
 327
 328 /*
 329  * For text based NFSv2/v3 mounts, the mount protocol transport default
 330  * settings should depend upon the specified NFS transport.
 331  */
 332 static void nfs_set_mount_transport_protocol(struct nfs_fs_context *ctx)
 333 {
 334         if (ctx->mount_server.protocol == XPRT_TRANSPORT_UDP ||
 335             ctx->mount_server.protocol == XPRT_TRANSPORT_TCP)
 336                         return;
 337         switch (ctx->nfs_server.protocol) {
 338         case XPRT_TRANSPORT_UDP:
 339                 ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
 340                 break;
 341         case XPRT_TRANSPORT_TCP:
 342         case XPRT_TRANSPORT_RDMA:
 343                 ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
 344         }
 345 }
 346
 347 /*
 348  * Add 'flavor' to 'auth_info' if not already present.
 349  * Returns true if 'flavor' ends up in the list, false otherwise
 350  */
 351 static int nfs_auth_info_add(struct fs_context *fc,
 352                              struct nfs_auth_info *auth_info,
 353                              rpc_authflavor_t flavor)
 354 {
 355         unsigned int i;
 356         unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
 357
 358         /* make sure this flavor isn't already in the list */
 359         for (i = 0; i < auth_info->flavor_len; i++) {
 360                 if (flavor == auth_info->flavors[i])
 361                         return 0;
 362         }
 363
 364         if (auth_info->flavor_len + 1 >= max_flavor_len)
 365                 return nfs_invalf(fc, "NFS: too many sec= flavors");
 366
 367         auth_info->flavors[auth_info->flavor_len++] = flavor;
 368         return 0;
 369 }
 370
 371 /*
 372  * Parse the value of the 'sec=' option.
 373  */
 374 static int nfs_parse_security_flavors(struct fs_context *fc,
 375                                       struct fs_parameter *param)
 376 {
 377         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 378         rpc_authflavor_t pseudoflavor;
 379         char *string = param->string, *p;
 380         int ret;
 381
 382         trace_nfs_mount_assign(param->key, string);
 383
 384         while ((p = strsep(&string, ":")) != NULL) {
 385                 if (!*p)
 386                         continue;
 387                 switch (lookup_constant(nfs_secflavor_tokens, p, -1)) {
 388                 case Opt_sec_none:
 389                         pseudoflavor = RPC_AUTH_NULL;
 390                         break;
 391                 case Opt_sec_sys:
 392                         pseudoflavor = RPC_AUTH_UNIX;
 393                         break;
 394                 case Opt_sec_krb5:
 395                         pseudoflavor = RPC_AUTH_GSS_KRB5;
 396                         break;
 397                 case Opt_sec_krb5i:
 398                         pseudoflavor = RPC_AUTH_GSS_KRB5I;
 399                         break;
 400                 case Opt_sec_krb5p:
 401                         pseudoflavor = RPC_AUTH_GSS_KRB5P;
 402                         break;
 403                 case Opt_sec_lkey:
 404                         pseudoflavor = RPC_AUTH_GSS_LKEY;
 405                         break;
 406                 case Opt_sec_lkeyi:
 407                         pseudoflavor = RPC_AUTH_GSS_LKEYI;
 408                         break;
 409                 case Opt_sec_lkeyp:
 410                         pseudoflavor = RPC_AUTH_GSS_LKEYP;
 411                         break;
 412                 case Opt_sec_spkm:
 413                         pseudoflavor = RPC_AUTH_GSS_SPKM;
 414                         break;
 415                 case Opt_sec_spkmi:
 416                         pseudoflavor = RPC_AUTH_GSS_SPKMI;
 417                         break;
 418                 case Opt_sec_spkmp:
 419                         pseudoflavor = RPC_AUTH_GSS_SPKMP;
 420                         break;
 421                 default:
 422                         return nfs_invalf(fc, "NFS: sec=%s option not recognized", p);
 423                 }
 424
 425                 ret = nfs_auth_info_add(fc, &ctx->auth_info, pseudoflavor);
 426                 if (ret < 0)
 427                         return ret;
 428         }
 429
 430         return 0;
 431 }
 432
 433 static int nfs_parse_version_string(struct fs_context *fc,
 434                                     const char *string)
 435 {
 436         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 437
 438         ctx->flags &= ~NFS_MOUNT_VER3;
 439         switch (lookup_constant(nfs_vers_tokens, string, -1)) {
 440         case Opt_vers_2:
 441                 ctx->version = 2;
 442                 break;
 443         case Opt_vers_3:
 444                 ctx->flags |= NFS_MOUNT_VER3;
 445                 ctx->version = 3;
 446                 break;
 447         case Opt_vers_4:
 448                 /* Backward compatibility option. In future,
 449                  * the mount program should always supply
 450                  * a NFSv4 minor version number.
 451                  */
 452                 ctx->version = 4;
 453                 break;
 454         case Opt_vers_4_0:
 455                 ctx->version = 4;
 456                 ctx->minorversion = 0;
 457                 break;
 458         case Opt_vers_4_1:
 459                 ctx->version = 4;
 460                 ctx->minorversion = 1;
 461                 break;
 462         case Opt_vers_4_2:
 463                 ctx->version = 4;
 464                 ctx->minorversion = 2;
 465                 break;
 466         default:
 467                 return nfs_invalf(fc, "NFS: Unsupported NFS version");
 468         }
 469         return 0;
 470 }
 471
 472 /*
 473  * Parse a single mount parameter.
 474  */
 475 static int nfs_fs_context_parse_param(struct fs_context *fc,
 476                                       struct fs_parameter *param)
 477 {
 478         struct fs_parse_result result;
 479         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 480         unsigned short protofamily, mountfamily;
 481         unsigned int len;
 482         int ret, opt;
 483
 484         trace_nfs_mount_option(param);
 485
 486         opt = fs_parse(fc, nfs_fs_parameters, param, &result);
 487         if (opt < 0)
 488                 return (opt == -ENOPARAM && ctx->sloppy) ? 1 : opt;
 489
 490         if (fc->security)
 491                 ctx->has_sec_mnt_opts = 1;
 492
 493         switch (opt) {
 494         case Opt_source:
 495                 if (fc->source)
 496                         return nfs_invalf(fc, "NFS: Multiple sources not supported");
 497                 fc->source = param->string;
 498                 param->string = NULL;
 499                 break;
 500
 501                 /*
 502                  * boolean options:  foo/nofoo
 503                  */
 504         case Opt_soft:
 505                 ctx->flags |= NFS_MOUNT_SOFT;
 506                 ctx->flags &= ~NFS_MOUNT_SOFTERR;
 507                 break;
 508         case Opt_softerr:
 509                 ctx->flags |= NFS_MOUNT_SOFTERR | NFS_MOUNT_SOFTREVAL;
 510                 ctx->flags &= ~NFS_MOUNT_SOFT;
 511                 break;
 512         case Opt_hard:
 513                 ctx->flags &= ~(NFS_MOUNT_SOFT |
 514                                 NFS_MOUNT_SOFTERR |
 515                                 NFS_MOUNT_SOFTREVAL);
 516                 break;
 517         case Opt_softreval:
 518                 if (result.negated)
 519                         ctx->flags &= ~NFS_MOUNT_SOFTREVAL;
 520                 else
 521                         ctx->flags |= NFS_MOUNT_SOFTREVAL;
 522                 break;
 523         case Opt_posix:
 524                 if (result.negated)
 525                         ctx->flags &= ~NFS_MOUNT_POSIX;
 526                 else
 527                         ctx->flags |= NFS_MOUNT_POSIX;
 528                 break;
 529         case Opt_cto:
 530                 if (result.negated)
 531                         ctx->flags |= NFS_MOUNT_NOCTO;
 532                 else
 533                         ctx->flags &= ~NFS_MOUNT_NOCTO;
 534                 break;
 535         case Opt_trunkdiscovery:
 536                 if (result.negated)
 537                         ctx->flags &= ~NFS_MOUNT_TRUNK_DISCOVERY;
 538                 else
 539                         ctx->flags |= NFS_MOUNT_TRUNK_DISCOVERY;
 540                 break;
 541         case Opt_ac:
 542                 if (result.negated)
 543                         ctx->flags |= NFS_MOUNT_NOAC;
 544                 else
 545                         ctx->flags &= ~NFS_MOUNT_NOAC;
 546                 break;
 547         case Opt_lock:
 548                 if (result.negated) {
 549                         ctx->flags |= NFS_MOUNT_NONLM;
 550                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
 551                 } else {
 552                         ctx->flags &= ~NFS_MOUNT_NONLM;
 553                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
 554                 }
 555                 break;
 556         case Opt_udp:
 557                 ctx->flags &= ~NFS_MOUNT_TCP;
 558                 ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 559                 break;
 560         case Opt_tcp:
 561         case Opt_rdma:
 562                 ctx->flags |= NFS_MOUNT_TCP; /* for side protocols */
 563                 ret = xprt_find_transport_ident(param->key);
 564                 if (ret < 0)
 565                         goto out_bad_transport;
 566                 ctx->nfs_server.protocol = ret;
 567                 break;
 568         case Opt_acl:
 569                 if (result.negated)
 570                         ctx->flags |= NFS_MOUNT_NOACL;
 571                 else
 572                         ctx->flags &= ~NFS_MOUNT_NOACL;
 573                 break;
 574         case Opt_rdirplus:
 575                 if (result.negated)
 576                         ctx->flags |= NFS_MOUNT_NORDIRPLUS;
 577                 else
 578                         ctx->flags &= ~NFS_MOUNT_NORDIRPLUS;
 579                 break;
 580         case Opt_sharecache:
 581                 if (result.negated)
 582                         ctx->flags |= NFS_MOUNT_UNSHARED;
 583                 else
 584                         ctx->flags &= ~NFS_MOUNT_UNSHARED;
 585                 break;
 586         case Opt_resvport:
 587                 if (result.negated)
 588                         ctx->flags |= NFS_MOUNT_NORESVPORT;
 589                 else
 590                         ctx->flags &= ~NFS_MOUNT_NORESVPORT;
 591                 break;
 592         case Opt_fscache_flag:
 593                 if (result.negated)
 594                         ctx->options &= ~NFS_OPTION_FSCACHE;
 595                 else
 596                         ctx->options |= NFS_OPTION_FSCACHE;
 597                 kfree(ctx->fscache_uniq);
 598                 ctx->fscache_uniq = NULL;
 599                 break;
 600         case Opt_fscache:
 601                 ctx->options |= NFS_OPTION_FSCACHE;
 602                 kfree(ctx->fscache_uniq);
 603                 ctx->fscache_uniq = param->string;
 604                 param->string = NULL;
 605                 break;
 606         case Opt_migration:
 607                 if (result.negated)
 608                         ctx->options &= ~NFS_OPTION_MIGRATION;
 609                 else
 610                         ctx->options |= NFS_OPTION_MIGRATION;
 611                 break;
 612
 613                 /*
 614                  * options that take numeric values
 615                  */
 616         case Opt_port:
 617                 if (result.uint_32 > USHRT_MAX)
 618                         goto out_of_bounds;
 619                 ctx->nfs_server.port = result.uint_32;
 620                 break;
 621         case Opt_rsize:
 622                 ctx->rsize = result.uint_32;
 623                 break;
 624         case Opt_wsize:
 625                 ctx->wsize = result.uint_32;
 626                 break;
 627         case Opt_bsize:
 628                 ctx->bsize = result.uint_32;
 629                 break;
 630         case Opt_timeo:
 631                 if (result.uint_32 < 1 || result.uint_32 > INT_MAX)
 632                         goto out_of_bounds;
 633                 ctx->timeo = result.uint_32;
 634                 break;
 635         case Opt_retrans:
 636                 if (result.uint_32 > INT_MAX)
 637                         goto out_of_bounds;
 638                 ctx->retrans = result.uint_32;
 639                 break;
 640         case Opt_acregmin:
 641                 ctx->acregmin = result.uint_32;
 642                 break;
 643         case Opt_acregmax:
 644                 ctx->acregmax = result.uint_32;
 645                 break;
 646         case Opt_acdirmin:
 647                 ctx->acdirmin = result.uint_32;
 648                 break;
 649         case Opt_acdirmax:
 650                 ctx->acdirmax = result.uint_32;
 651                 break;
 652         case Opt_actimeo:
 653                 ctx->acregmin = result.uint_32;
 654                 ctx->acregmax = result.uint_32;
 655                 ctx->acdirmin = result.uint_32;
 656                 ctx->acdirmax = result.uint_32;
 657                 break;
 658         case Opt_namelen:
 659                 ctx->namlen = result.uint_32;
 660                 break;
 661         case Opt_mountport:
 662                 if (result.uint_32 > USHRT_MAX)
 663                         goto out_of_bounds;
 664                 ctx->mount_server.port = result.uint_32;
 665                 break;
 666         case Opt_mountvers:
 667                 if (result.uint_32 < NFS_MNT_VERSION ||
 668                     result.uint_32 > NFS_MNT3_VERSION)
 669                         goto out_of_bounds;
 670                 ctx->mount_server.version = result.uint_32;
 671                 break;
 672         case Opt_minorversion:
 673                 if (result.uint_32 > NFS4_MAX_MINOR_VERSION)
 674                         goto out_of_bounds;
 675                 ctx->minorversion = result.uint_32;
 676                 break;
 677
 678                 /*
 679                  * options that take text values
 680                  */
 681         case Opt_v:
 682                 ret = nfs_parse_version_string(fc, param->key + 1);
 683                 if (ret < 0)
 684                         return ret;
 685                 break;
 686         case Opt_vers:
 687                 trace_nfs_mount_assign(param->key, param->string);
 688                 ret = nfs_parse_version_string(fc, param->string);
 689                 if (ret < 0)
 690                         return ret;
 691                 break;
 692         case Opt_sec:
 693                 ret = nfs_parse_security_flavors(fc, param);
 694                 if (ret < 0)
 695                         return ret;
 696                 break;
 697
 698         case Opt_proto:
 699                 trace_nfs_mount_assign(param->key, param->string);
 700                 protofamily = AF_INET;
 701                 switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
 702                 case Opt_xprt_udp6:
 703                         protofamily = AF_INET6;
 704                         fallthrough;
 705                 case Opt_xprt_udp:
 706                         ctx->flags &= ~NFS_MOUNT_TCP;
 707                         ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
 708                         break;
 709                 case Opt_xprt_tcp6:
 710                         protofamily = AF_INET6;
 711                         fallthrough;
 712                 case Opt_xprt_tcp:
 713                         ctx->flags |= NFS_MOUNT_TCP;
 714                         ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 715                         break;
 716                 case Opt_xprt_rdma6:
 717                         protofamily = AF_INET6;
 718                         fallthrough;
 719                 case Opt_xprt_rdma:
 720                         /* vector side protocols to TCP */
 721                         ctx->flags |= NFS_MOUNT_TCP;
 722                         ret = xprt_find_transport_ident(param->string);
 723                         if (ret < 0)
 724                                 goto out_bad_transport;
 725                         ctx->nfs_server.protocol = ret;
 726                         break;
 727                 default:
 728                         goto out_bad_transport;
 729                 }
 730
 731                 ctx->protofamily = protofamily;
 732                 break;
 733
 734         case Opt_mountproto:
 735                 trace_nfs_mount_assign(param->key, param->string);
 736                 mountfamily = AF_INET;
 737                 switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
 738                 case Opt_xprt_udp6:
 739                         mountfamily = AF_INET6;
 740                         fallthrough;
 741                 case Opt_xprt_udp:
 742                         ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
 743                         break;
 744                 case Opt_xprt_tcp6:
 745                         mountfamily = AF_INET6;
 746                         fallthrough;
 747                 case Opt_xprt_tcp:
 748                         ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
 749                         break;
 750                 case Opt_xprt_rdma: /* not used for side protocols */
 751                 default:
 752                         goto out_bad_transport;
 753                 }
 754                 ctx->mountfamily = mountfamily;
 755                 break;
 756
 757         case Opt_addr:
 758                 trace_nfs_mount_assign(param->key, param->string);
 759                 len = rpc_pton(fc->net_ns, param->string, param->size,
 760                                &ctx->nfs_server.address,
 761                                sizeof(ctx->nfs_server._address));
 762                 if (len == 0)
 763                         goto out_invalid_address;
 764                 ctx->nfs_server.addrlen = len;
 765                 break;
 766         case Opt_clientaddr:
 767                 trace_nfs_mount_assign(param->key, param->string);
 768                 kfree(ctx->client_address);
 769                 ctx->client_address = param->string;
 770                 param->string = NULL;
 771                 break;
 772         case Opt_mounthost:
 773                 trace_nfs_mount_assign(param->key, param->string);
 774                 kfree(ctx->mount_server.hostname);
 775                 ctx->mount_server.hostname = param->string;
 776                 param->string = NULL;
 777                 break;
 778         case Opt_mountaddr:
 779                 trace_nfs_mount_assign(param->key, param->string);
 780                 len = rpc_pton(fc->net_ns, param->string, param->size,
 781                                &ctx->mount_server.address,
 782                                sizeof(ctx->mount_server._address));
 783                 if (len == 0)
 784                         goto out_invalid_address;
 785                 ctx->mount_server.addrlen = len;
 786                 break;
 787         case Opt_nconnect:
 788                 if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_CONNECTIONS)
 789                         goto out_of_bounds;
 790                 ctx->nfs_server.nconnect = result.uint_32;
 791                 break;
 792         case Opt_max_connect:
 793                 if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_TRANSPORTS)
 794                         goto out_of_bounds;
 795                 ctx->nfs_server.max_connect = result.uint_32;
 796                 break;
 797         case Opt_lookupcache:
 798                 switch (result.uint_32) {
 799                 case Opt_lookupcache_all:
 800                         ctx->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
 801                         break;
 802                 case Opt_lookupcache_positive:
 803                         ctx->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
 804                         ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
 805                         break;
 806                 case Opt_lookupcache_none:
 807                         ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
 808                         break;
 809                 default:
 810                         goto out_invalid_value;
 811                 }
 812                 break;
 813         case Opt_local_lock:
 814                 switch (result.uint_32) {
 815                 case Opt_local_lock_all:
 816                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK |
 817                                        NFS_MOUNT_LOCAL_FCNTL);
 818                         break;
 819                 case Opt_local_lock_flock:
 820                         ctx->flags |= NFS_MOUNT_LOCAL_FLOCK;
 821                         break;
 822                 case Opt_local_lock_posix:
 823                         ctx->flags |= NFS_MOUNT_LOCAL_FCNTL;
 824                         break;
 825                 case Opt_local_lock_none:
 826                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
 827                                         NFS_MOUNT_LOCAL_FCNTL);
 828                         break;
 829                 default:
 830                         goto out_invalid_value;
 831                 }
 832                 break;
 833         case Opt_write:
 834                 switch (result.uint_32) {
 835                 case Opt_write_lazy:
 836                         ctx->flags &=
 837                                 ~(NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT);
 838                         break;
 839                 case Opt_write_eager:
 840                         ctx->flags |= NFS_MOUNT_WRITE_EAGER;
 841                         ctx->flags &= ~NFS_MOUNT_WRITE_WAIT;
 842                         break;
 843                 case Opt_write_wait:
 844                         ctx->flags |=
 845                                 NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT;
 846                         break;
 847                 default:
 848                         goto out_invalid_value;
 849                 }
 850                 break;
 851
 852                 /*
 853                  * Special options
 854                  */
 855         case Opt_sloppy:
 856                 ctx->sloppy = true;
 857                 break;
 858         }
 859
 860         return 0;
 861
 862 out_invalid_value:
 863         return nfs_invalf(fc, "NFS: Bad mount option value specified");
 864 out_invalid_address:
 865         return nfs_invalf(fc, "NFS: Bad IP address specified");
 866 out_of_bounds:
 867         return nfs_invalf(fc, "NFS: Value for '%s' out of range", param->key);
 868 out_bad_transport:
 869         return nfs_invalf(fc, "NFS: Unrecognized transport protocol");
 870 }
 871
 872 /*
 873  * Split fc->source into "hostname:export_path".
 874  *
 875  * The leftmost colon demarks the split between the server's hostname
 876  * and the export path.  If the hostname starts with a left square
 877  * bracket, then it may contain colons.
 878  *
 879  * Note: caller frees hostname and export path, even on error.
 880  */
 881 static int nfs_parse_source(struct fs_context *fc,
 882                             size_t maxnamlen, size_t maxpathlen)
 883 {
 884         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 885         const char *dev_name = fc->source;
 886         size_t len;
 887         const char *end;
 888
 889         if (unlikely(!dev_name || !*dev_name))
 890                 return -EINVAL;
 891
 892         /* Is the host name protected with square brakcets? */
 893         if (*dev_name == '[') {
 894                 end = strchr(++dev_name, ']');
 895                 if (end == NULL || end[1] != ':')
 896                         goto out_bad_devname;
 897
 898                 len = end - dev_name;
 899                 end++;
 900         } else {
 901                 const char *comma;
 902
 903                 end = strchr(dev_name, ':');
 904                 if (end == NULL)
 905                         goto out_bad_devname;
 906                 len = end - dev_name;
 907
 908                 /* kill possible hostname list: not supported */
 909                 comma = memchr(dev_name, ',', len);
 910                 if (comma)
 911                         len = comma - dev_name;
 912         }
 913
 914         if (len > maxnamlen)
 915                 goto out_hostname;
 916
 917         kfree(ctx->nfs_server.hostname);
 918
 919         /* N.B. caller will free nfs_server.hostname in all cases */
 920         ctx->nfs_server.hostname = kmemdup_nul(dev_name, len, GFP_KERNEL);
 921         if (!ctx->nfs_server.hostname)
 922                 goto out_nomem;
 923         len = strlen(++end);
 924         if (len > maxpathlen)
 925                 goto out_path;
 926         ctx->nfs_server.export_path = kmemdup_nul(end, len, GFP_KERNEL);
 927         if (!ctx->nfs_server.export_path)
 928                 goto out_nomem;
 929
 930         trace_nfs_mount_path(ctx->nfs_server.export_path);
 931         return 0;
 932
 933 out_bad_devname:
 934         return nfs_invalf(fc, "NFS: device name not in host:path format");
 935 out_nomem:
 936         nfs_errorf(fc, "NFS: not enough memory to parse device name");
 937         return -ENOMEM;
 938 out_hostname:
 939         nfs_errorf(fc, "NFS: server hostname too long");
 940         return -ENAMETOOLONG;
 941 out_path:
 942         nfs_errorf(fc, "NFS: export pathname too long");
 943         return -ENAMETOOLONG;
 944 }
 945
 946 static inline bool is_remount_fc(struct fs_context *fc)
 947 {
 948         return fc->root != NULL;
 949 }
 950
 951 /*
 952  * Parse monolithic NFS2/NFS3 mount data
 953  * - fills in the mount root filehandle
 954  *
 955  * For option strings, user space handles the following behaviors:
 956  *
 957  * + DNS: mapping server host name to IP address ("addr=" option)
 958  *
 959  * + failure mode: how to behave if a mount request can't be handled
 960  *   immediately ("fg/bg" option)
 961  *
 962  * + retry: how often to retry a mount request ("retry=" option)
 963  *
 964  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
 965  *   mountproto=tcp after mountproto=udp, and so on
 966  */
 967 static int nfs23_parse_monolithic(struct fs_context *fc,
 968                                   struct nfs_mount_data *data)
 969 {
 970         struct nfs_fs_context *ctx = nfs_fc2context(fc);
 971         struct nfs_fh *mntfh = ctx->mntfh;
 972         struct sockaddr_storage *sap = &ctx->nfs_server._address;
 973         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
 974         int ret;
 975
 976         if (data == NULL)
 977                 goto out_no_data;
 978
 979         ctx->version = NFS_DEFAULT_VERSION;
 980         switch (data->version) {
 981         case 1:
 982                 data->namlen = 0;
 983                 fallthrough;
 984         case 2:
 985                 data->bsize = 0;
 986                 fallthrough;
 987         case 3:
 988                 if (data->flags & NFS_MOUNT_VER3)
 989                         goto out_no_v3;
 990                 data->root.size = NFS2_FHSIZE;
 991                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
 992                 /* Turn off security negotiation */
 993                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
 994                 fallthrough;
 995         case 4:
 996                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
 997                         goto out_no_sec;
 998                 fallthrough;
 999         case 5:
1000                 memset(data->context, 0, sizeof(data->context));
1001                 fallthrough;
1002         case 6:
1003                 if (data->flags & NFS_MOUNT_VER3) {
1004                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1005                                 goto out_invalid_fh;
1006                         mntfh->size = data->root.size;
1007                         ctx->version = 3;
1008                 } else {
1009                         mntfh->size = NFS2_FHSIZE;
1010                         ctx->version = 2;
1011                 }
1012
1013
1014                 memcpy(mntfh->data, data->root.data, mntfh->size);
1015                 if (mntfh->size < sizeof(mntfh->data))
1016                         memset(mntfh->data + mntfh->size, 0,
1017                                sizeof(mntfh->data) - mntfh->size);
1018
1019                 /*
1020                  * for proto == XPRT_TRANSPORT_UDP, which is what uses
1021                  * to_exponential, implying shift: limit the shift value
1022                  * to BITS_PER_LONG (majortimeo is unsigned long)
1023                  */
1024                 if (!(data->flags & NFS_MOUNT_TCP)) /* this will be UDP */
1025                         if (data->retrans >= 64) /* shift value is too large */
1026                                 goto out_invalid_data;
1027
1028                 /*
1029                  * Translate to nfs_fs_context, which nfs_fill_super
1030                  * can deal with.
1031                  */
1032                 ctx->flags      = data->flags & NFS_MOUNT_FLAGMASK;
1033                 ctx->flags      |= extra_flags;
1034                 ctx->rsize      = data->rsize;
1035                 ctx->wsize      = data->wsize;
1036                 ctx->timeo      = data->timeo;
1037                 ctx->retrans    = data->retrans;
1038                 ctx->acregmin   = data->acregmin;
1039                 ctx->acregmax   = data->acregmax;
1040                 ctx->acdirmin   = data->acdirmin;
1041                 ctx->acdirmax   = data->acdirmax;
1042                 ctx->need_mount = false;
1043
1044                 memcpy(sap, &data->addr, sizeof(data->addr));
1045                 ctx->nfs_server.addrlen = sizeof(data->addr);
1046                 ctx->nfs_server.port = ntohs(data->addr.sin_port);
1047                 if (sap->ss_family != AF_INET ||
1048                     !nfs_verify_server_address(sap))
1049                         goto out_no_address;
1050
1051                 if (!(data->flags & NFS_MOUNT_TCP))
1052                         ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1053                 /* N.B. caller will free nfs_server.hostname in all cases */
1054                 ctx->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1055                 if (!ctx->nfs_server.hostname)
1056                         goto out_nomem;
1057
1058                 ctx->namlen             = data->namlen;
1059                 ctx->bsize              = data->bsize;
1060
1061                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1062                         ctx->selected_flavor = data->pseudoflavor;
1063                 else
1064                         ctx->selected_flavor = RPC_AUTH_UNIX;
1065
1066                 if (!(data->flags & NFS_MOUNT_NONLM))
1067                         ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1068                                          NFS_MOUNT_LOCAL_FCNTL);
1069                 else
1070                         ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1071                                         NFS_MOUNT_LOCAL_FCNTL);
1072
1073                 /*
1074                  * The legacy version 6 binary mount data from userspace has a
1075                  * field used only to transport selinux information into the
1076                  * kernel.  To continue to support that functionality we
1077                  * have a touch of selinux knowledge here in the NFS code. The
1078                  * userspace code converted context=blah to just blah so we are
1079                  * converting back to the full string selinux understands.
1080                  */
1081                 if (data->context[0]){
1082 #ifdef CONFIG_SECURITY_SELINUX
1083                         int ret;
1084
1085                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1086                         ret = vfs_parse_fs_string(fc, "context",
1087                                                   data->context, strlen(data->context));
1088                         if (ret < 0)
1089                                 return ret;
1090 #else
1091                         return -EINVAL;
1092 #endif
1093                 }
1094
1095                 break;
1096         default:
1097                 goto generic;
1098         }
1099
1100         ret = nfs_validate_transport_protocol(fc, ctx);
1101         if (ret)
1102                 return ret;
1103
1104         ctx->skip_reconfig_option_check = true;
1105         return 0;
1106
1107 generic:
1108         return generic_parse_monolithic(fc, data);
1109
1110 out_no_data:
1111         if (is_remount_fc(fc)) {
1112                 ctx->skip_reconfig_option_check = true;
1113                 return 0;
1114         }
1115         return nfs_invalf(fc, "NFS: mount program didn't pass any mount data");
1116
1117 out_no_v3:
1118         return nfs_invalf(fc, "NFS: nfs_mount_data version does not support v3");
1119
1120 out_no_sec:
1121         return nfs_invalf(fc, "NFS: nfs_mount_data version supports only AUTH_SYS");
1122
1123 out_nomem:
1124         return -ENOMEM;
1125
1126 out_no_address:
1127         return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1128
1129 out_invalid_fh:
1130         return nfs_invalf(fc, "NFS: invalid root filehandle");
1131
1132 out_invalid_data:
1133         return nfs_invalf(fc, "NFS: invalid binary mount data");
1134 }
1135
1136 #if IS_ENABLED(CONFIG_NFS_V4)
1137 struct compat_nfs_string {
1138         compat_uint_t len;
1139         compat_uptr_t data;
1140 };
1141
1142 static inline void compat_nfs_string(struct nfs_string *dst,
1143                                      struct compat_nfs_string *src)
1144 {
1145         dst->data = compat_ptr(src->data);
1146         dst->len = src->len;
1147 }
1148
1149 struct compat_nfs4_mount_data_v1 {
1150         compat_int_t version;
1151         compat_int_t flags;
1152         compat_int_t rsize;
1153         compat_int_t wsize;
1154         compat_int_t timeo;
1155         compat_int_t retrans;
1156         compat_int_t acregmin;
1157         compat_int_t acregmax;
1158         compat_int_t acdirmin;
1159         compat_int_t acdirmax;
1160         struct compat_nfs_string client_addr;
1161         struct compat_nfs_string mnt_path;
1162         struct compat_nfs_string hostname;
1163         compat_uint_t host_addrlen;
1164         compat_uptr_t host_addr;
1165         compat_int_t proto;
1166         compat_int_t auth_flavourlen;
1167         compat_uptr_t auth_flavours;
1168 };
1169
1170 static void nfs4_compat_mount_data_conv(struct nfs4_mount_data *data)
1171 {
1172         struct compat_nfs4_mount_data_v1 *compat =
1173                         (struct compat_nfs4_mount_data_v1 *)data;
1174
1175         /* copy the fields backwards */
1176         data->auth_flavours = compat_ptr(compat->auth_flavours);
1177         data->auth_flavourlen = compat->auth_flavourlen;
1178         data->proto = compat->proto;
1179         data->host_addr = compat_ptr(compat->host_addr);
1180         data->host_addrlen = compat->host_addrlen;
1181         compat_nfs_string(&data->hostname, &compat->hostname);
1182         compat_nfs_string(&data->mnt_path, &compat->mnt_path);
1183         compat_nfs_string(&data->client_addr, &compat->client_addr);
1184         data->acdirmax = compat->acdirmax;
1185         data->acdirmin = compat->acdirmin;
1186         data->acregmax = compat->acregmax;
1187         data->acregmin = compat->acregmin;
1188         data->retrans = compat->retrans;
1189         data->timeo = compat->timeo;
1190         data->wsize = compat->wsize;
1191         data->rsize = compat->rsize;
1192         data->flags = compat->flags;
1193         data->version = compat->version;
1194 }
1195
1196 /*
1197  * Validate NFSv4 mount options
1198  */
1199 static int nfs4_parse_monolithic(struct fs_context *fc,
1200                                  struct nfs4_mount_data *data)
1201 {
1202         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1203         struct sockaddr_storage *sap = &ctx->nfs_server._address;
1204         int ret;
1205         char *c;
1206
1207         if (!data) {
1208                 if (is_remount_fc(fc))
1209                         goto done;
1210                 return nfs_invalf(fc,
1211                         "NFS4: mount program didn't pass any mount data");
1212         }
1213
1214         ctx->version = 4;
1215
1216         if (data->version != 1)
1217                 return generic_parse_monolithic(fc, data);
1218
1219         if (in_compat_syscall())
1220                 nfs4_compat_mount_data_conv(data);
1221
1222         if (data->host_addrlen > sizeof(ctx->nfs_server.address))
1223                 goto out_no_address;
1224         if (data->host_addrlen == 0)
1225                 goto out_no_address;
1226         ctx->nfs_server.addrlen = data->host_addrlen;
1227         if (copy_from_user(sap, data->host_addr, data->host_addrlen))
1228                 return -EFAULT;
1229         if (!nfs_verify_server_address(sap))
1230                 goto out_no_address;
1231         ctx->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
1232
1233         if (data->auth_flavourlen) {
1234                 rpc_authflavor_t pseudoflavor;
1235
1236                 if (data->auth_flavourlen > 1)
1237                         goto out_inval_auth;
1238                 if (copy_from_user(&pseudoflavor, data->auth_flavours,
1239                                    sizeof(pseudoflavor)))
1240                         return -EFAULT;
1241                 ctx->selected_flavor = pseudoflavor;
1242         } else {
1243                 ctx->selected_flavor = RPC_AUTH_UNIX;
1244         }
1245
1246         c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1247         if (IS_ERR(c))
1248                 return PTR_ERR(c);
1249         ctx->nfs_server.hostname = c;
1250
1251         c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1252         if (IS_ERR(c))
1253                 return PTR_ERR(c);
1254         ctx->nfs_server.export_path = c;
1255         trace_nfs_mount_path(c);
1256
1257         c = strndup_user(data->client_addr.data, 16);
1258         if (IS_ERR(c))
1259                 return PTR_ERR(c);
1260         ctx->client_address = c;
1261
1262         /*
1263          * Translate to nfs_fs_context, which nfs_fill_super
1264          * can deal with.
1265          */
1266
1267         ctx->flags      = data->flags & NFS4_MOUNT_FLAGMASK;
1268         ctx->rsize      = data->rsize;
1269         ctx->wsize      = data->wsize;
1270         ctx->timeo      = data->timeo;
1271         ctx->retrans    = data->retrans;
1272         ctx->acregmin   = data->acregmin;
1273         ctx->acregmax   = data->acregmax;
1274         ctx->acdirmin   = data->acdirmin;
1275         ctx->acdirmax   = data->acdirmax;
1276         ctx->nfs_server.protocol = data->proto;
1277         ret = nfs_validate_transport_protocol(fc, ctx);
1278         if (ret)
1279                 return ret;
1280 done:
1281         ctx->skip_reconfig_option_check = true;
1282         return 0;
1283
1284 out_inval_auth:
1285         return nfs_invalf(fc, "NFS4: Invalid number of RPC auth flavours %d",
1286                       data->auth_flavourlen);
1287
1288 out_no_address:
1289         return nfs_invalf(fc, "NFS4: mount program didn't pass remote address");
1290 }
1291 #endif
1292
1293 /*
1294  * Parse a monolithic block of data from sys_mount().
1295  */
1296 static int nfs_fs_context_parse_monolithic(struct fs_context *fc,
1297                                            void *data)
1298 {
1299         if (fc->fs_type == &nfs_fs_type)
1300                 return nfs23_parse_monolithic(fc, data);
1301
1302 #if IS_ENABLED(CONFIG_NFS_V4)
1303         if (fc->fs_type == &nfs4_fs_type)
1304                 return nfs4_parse_monolithic(fc, data);
1305 #endif
1306
1307         return nfs_invalf(fc, "NFS: Unsupported monolithic data version");
1308 }
1309
1310 /*
1311  * Validate the preparsed information in the config.
1312  */
1313 static int nfs_fs_context_validate(struct fs_context *fc)
1314 {
1315         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1316         struct nfs_subversion *nfs_mod;
1317         struct sockaddr_storage *sap = &ctx->nfs_server._address;
1318         int max_namelen = PAGE_SIZE;
1319         int max_pathlen = NFS_MAXPATHLEN;
1320         int port = 0;
1321         int ret;
1322
1323         if (!fc->source)
1324                 goto out_no_device_name;
1325
1326         /* Check for sanity first. */
1327         if (ctx->minorversion && ctx->version != 4)
1328                 goto out_minorversion_mismatch;
1329
1330         if (ctx->options & NFS_OPTION_MIGRATION &&
1331             (ctx->version != 4 || ctx->minorversion != 0))
1332                 goto out_migration_misuse;
1333
1334         /* Verify that any proto=/mountproto= options match the address
1335          * families in the addr=/mountaddr= options.
1336          */
1337         if (ctx->protofamily != AF_UNSPEC &&
1338             ctx->protofamily != ctx->nfs_server.address.sa_family)
1339                 goto out_proto_mismatch;
1340
1341         if (ctx->mountfamily != AF_UNSPEC) {
1342                 if (ctx->mount_server.addrlen) {
1343                         if (ctx->mountfamily != ctx->mount_server.address.sa_family)
1344                                 goto out_mountproto_mismatch;
1345                 } else {
1346                         if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
1347                                 goto out_mountproto_mismatch;
1348                 }
1349         }
1350
1351         if (!nfs_verify_server_address(sap))
1352                 goto out_no_address;
1353
1354         ret = nfs_validate_transport_protocol(fc, ctx);
1355         if (ret)
1356                 return ret;
1357
1358         if (ctx->version == 4) {
1359                 if (IS_ENABLED(CONFIG_NFS_V4)) {
1360                         if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1361                                 port = NFS_RDMA_PORT;
1362                         else
1363                                 port = NFS_PORT;
1364                         max_namelen = NFS4_MAXNAMLEN;
1365                         max_pathlen = NFS4_MAXPATHLEN;
1366                         ctx->flags &= ~(NFS_MOUNT_NONLM | NFS_MOUNT_NOACL |
1367                                         NFS_MOUNT_VER3 | NFS_MOUNT_LOCAL_FLOCK |
1368                                         NFS_MOUNT_LOCAL_FCNTL);
1369                 } else {
1370                         goto out_v4_not_compiled;
1371                 }
1372         } else {
1373                 nfs_set_mount_transport_protocol(ctx);
1374                 if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1375                         port = NFS_RDMA_PORT;
1376         }
1377
1378         nfs_set_port(sap, &ctx->nfs_server.port, port);
1379
1380         ret = nfs_parse_source(fc, max_namelen, max_pathlen);
1381         if (ret < 0)
1382                 return ret;
1383
1384         /* Load the NFS protocol module if we haven't done so yet */
1385         if (!ctx->nfs_mod) {
1386                 nfs_mod = get_nfs_version(ctx->version);
1387                 if (IS_ERR(nfs_mod)) {
1388                         ret = PTR_ERR(nfs_mod);
1389                         goto out_version_unavailable;
1390                 }
1391                 ctx->nfs_mod = nfs_mod;
1392         }
1393
1394         /* Ensure the filesystem context has the correct fs_type */
1395         if (fc->fs_type != ctx->nfs_mod->nfs_fs) {
1396                 module_put(fc->fs_type->owner);
1397                 __module_get(ctx->nfs_mod->nfs_fs->owner);
1398                 fc->fs_type = ctx->nfs_mod->nfs_fs;
1399         }
1400         return 0;
1401
1402 out_no_device_name:
1403         return nfs_invalf(fc, "NFS: Device name not specified");
1404 out_v4_not_compiled:
1405         nfs_errorf(fc, "NFS: NFSv4 is not compiled into kernel");
1406         return -EPROTONOSUPPORT;
1407 out_no_address:
1408         return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1409 out_mountproto_mismatch:
1410         return nfs_invalf(fc, "NFS: Mount server address does not match mountproto= option");
1411 out_proto_mismatch:
1412         return nfs_invalf(fc, "NFS: Server address does not match proto= option");
1413 out_minorversion_mismatch:
1414         return nfs_invalf(fc, "NFS: Mount option vers=%u does not support minorversion=%u",
1415                           ctx->version, ctx->minorversion);
1416 out_migration_misuse:
1417         return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS version");
1418 out_version_unavailable:
1419         nfs_errorf(fc, "NFS: Version unavailable");
1420         return ret;
1421 }
1422
1423 /*
1424  * Create an NFS superblock by the appropriate method.
1425  */
1426 static int nfs_get_tree(struct fs_context *fc)
1427 {
1428         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1429         int err = nfs_fs_context_validate(fc);
1430
1431         if (err)
1432                 return err;
1433         if (!ctx->internal)
1434                 return ctx->nfs_mod->rpc_ops->try_get_tree(fc);
1435         else
1436                 return nfs_get_tree_common(fc);
1437 }
1438
1439 /*
1440  * Handle duplication of a configuration.  The caller copied *src into *sc, but
1441  * it can't deal with resource pointers in the filesystem context, so we have
1442  * to do that.  We need to clear pointers, copy data or get extra refs as
1443  * appropriate.
1444  */
1445 static int nfs_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1446 {
1447         struct nfs_fs_context *src = nfs_fc2context(src_fc), *ctx;
1448
1449         ctx = kmemdup(src, sizeof(struct nfs_fs_context), GFP_KERNEL);
1450         if (!ctx)
1451                 return -ENOMEM;
1452
1453         ctx->mntfh = nfs_alloc_fhandle();
1454         if (!ctx->mntfh) {
1455                 kfree(ctx);
1456                 return -ENOMEM;
1457         }
1458         nfs_copy_fh(ctx->mntfh, src->mntfh);
1459
1460         __module_get(ctx->nfs_mod->owner);
1461         ctx->client_address             = NULL;
1462         ctx->mount_server.hostname      = NULL;
1463         ctx->nfs_server.export_path     = NULL;
1464         ctx->nfs_server.hostname        = NULL;
1465         ctx->fscache_uniq               = NULL;
1466         ctx->clone_data.fattr           = NULL;
1467         fc->fs_private = ctx;
1468         return 0;
1469 }
1470
1471 static void nfs_fs_context_free(struct fs_context *fc)
1472 {
1473         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1474
1475         if (ctx) {
1476                 if (ctx->server)
1477                         nfs_free_server(ctx->server);
1478                 if (ctx->nfs_mod)
1479                         put_nfs_version(ctx->nfs_mod);
1480                 kfree(ctx->client_address);
1481                 kfree(ctx->mount_server.hostname);
1482                 kfree(ctx->nfs_server.export_path);
1483                 kfree(ctx->nfs_server.hostname);
1484                 kfree(ctx->fscache_uniq);
1485                 nfs_free_fhandle(ctx->mntfh);
1486                 nfs_free_fattr(ctx->clone_data.fattr);
1487                 kfree(ctx);
1488         }
1489 }
1490
1491 static const struct fs_context_operations nfs_fs_context_ops = {
1492         .free                   = nfs_fs_context_free,
1493         .dup                    = nfs_fs_context_dup,
1494         .parse_param            = nfs_fs_context_parse_param,
1495         .parse_monolithic       = nfs_fs_context_parse_monolithic,
1496         .get_tree               = nfs_get_tree,
1497         .reconfigure            = nfs_reconfigure,
1498 };
1499
1500 /*
1501  * Prepare superblock configuration.  We use the namespaces attached to the
1502  * context.  This may be the current process's namespaces, or it may be a
1503  * container's namespaces.
1504  */
1505 static int nfs_init_fs_context(struct fs_context *fc)
1506 {
1507         struct nfs_fs_context *ctx;
1508
1509         ctx = kzalloc(sizeof(struct nfs_fs_context), GFP_KERNEL);
1510         if (unlikely(!ctx))
1511                 return -ENOMEM;
1512
1513         ctx->mntfh = nfs_alloc_fhandle();
1514         if (unlikely(!ctx->mntfh)) {
1515                 kfree(ctx);
1516                 return -ENOMEM;
1517         }
1518
1519         ctx->protofamily        = AF_UNSPEC;
1520         ctx->mountfamily        = AF_UNSPEC;
1521         ctx->mount_server.port  = NFS_UNSPEC_PORT;
1522
1523         if (fc->root) {
1524                 /* reconfigure, start with the current config */
1525                 struct nfs_server *nfss = fc->root->d_sb->s_fs_info;
1526                 struct net *net = nfss->nfs_client->cl_net;
1527
1528                 ctx->flags              = nfss->flags;
1529                 ctx->rsize              = nfss->rsize;
1530                 ctx->wsize              = nfss->wsize;
1531                 ctx->retrans            = nfss->client->cl_timeout->to_retries;
1532                 ctx->selected_flavor    = nfss->client->cl_auth->au_flavor;
1533                 ctx->acregmin           = nfss->acregmin / HZ;
1534                 ctx->acregmax           = nfss->acregmax / HZ;
1535                 ctx->acdirmin           = nfss->acdirmin / HZ;
1536                 ctx->acdirmax           = nfss->acdirmax / HZ;
1537                 ctx->timeo              = 10U * nfss->client->cl_timeout->to_initval / HZ;
1538                 ctx->nfs_server.port    = nfss->port;
1539                 ctx->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
1540                 ctx->version            = nfss->nfs_client->rpc_ops->version;
1541                 ctx->minorversion       = nfss->nfs_client->cl_minorversion;
1542
1543                 memcpy(&ctx->nfs_server._address, &nfss->nfs_client->cl_addr,
1544                         ctx->nfs_server.addrlen);
1545
1546                 if (fc->net_ns != net) {
1547                         put_net(fc->net_ns);
1548                         fc->net_ns = get_net(net);
1549                 }
1550
1551                 ctx->nfs_mod = nfss->nfs_client->cl_nfs_mod;
1552                 __module_get(ctx->nfs_mod->owner);
1553         } else {
1554                 /* defaults */
1555                 ctx->timeo              = NFS_UNSPEC_TIMEO;
1556                 ctx->retrans            = NFS_UNSPEC_RETRANS;
1557                 ctx->acregmin           = NFS_DEF_ACREGMIN;
1558                 ctx->acregmax           = NFS_DEF_ACREGMAX;
1559                 ctx->acdirmin           = NFS_DEF_ACDIRMIN;
1560                 ctx->acdirmax           = NFS_DEF_ACDIRMAX;
1561                 ctx->nfs_server.port    = NFS_UNSPEC_PORT;
1562                 ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1563                 ctx->selected_flavor    = RPC_AUTH_MAXFLAVOR;
1564                 ctx->minorversion       = 0;
1565                 ctx->need_mount         = true;
1566
1567                 fc->s_iflags            |= SB_I_STABLE_WRITES;
1568         }
1569         fc->fs_private = ctx;
1570         fc->ops = &nfs_fs_context_ops;
1571         return 0;
1572 }
1573
1574 struct file_system_type nfs_fs_type = {
1575         .owner                  = THIS_MODULE,
1576         .name                   = "nfs",
1577         .init_fs_context        = nfs_init_fs_context,
1578         .parameters             = nfs_fs_parameters,
1579         .kill_sb                = nfs_kill_super,
1580         .fs_flags               = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1581 };
1582 MODULE_ALIAS_FS("nfs");
1583 EXPORT_SYMBOL_GPL(nfs_fs_type);
1584
1585 #if IS_ENABLED(CONFIG_NFS_V4)
1586 struct file_system_type nfs4_fs_type = {
1587         .owner                  = THIS_MODULE,
1588         .name                   = "nfs4",
1589         .init_fs_context        = nfs_init_fs_context,
1590         .parameters             = nfs_fs_parameters,
1591         .kill_sb                = nfs_kill_super,
1592         .fs_flags               = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1593 };
1594 MODULE_ALIAS_FS("nfs4");
1595 MODULE_ALIAS("nfs4");
1596 EXPORT_SYMBOL_GPL(nfs4_fs_type);
1597 #endif /* CONFIG_NFS_V4 */