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