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