Version:  2.0.40 2.2.26 2.4.37 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 3.18 3.19 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7

Linux/fs/nfs/super.c

  1 /*
  2  *  linux/fs/nfs/super.c
  3  *
  4  *  Copyright (C) 1992  Rick Sladkey
  5  *
  6  *  nfs superblock handling functions
  7  *
  8  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
  9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
 10  *
 11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
 12  *  J.S.Peatfield@damtp.cam.ac.uk
 13  *
 14  *  Split from inode.c by David Howells <dhowells@redhat.com>
 15  *
 16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
 17  *   particular server are held in the same superblock
 18  * - NFS superblocks can have several effective roots to the dentry tree
 19  * - directory type roots are spliced into the tree when a path from one root reaches the root
 20  *   of another (see nfs_lookup())
 21  */
 22 
 23 #include <linux/module.h>
 24 #include <linux/init.h>
 25 
 26 #include <linux/time.h>
 27 #include <linux/kernel.h>
 28 #include <linux/mm.h>
 29 #include <linux/string.h>
 30 #include <linux/stat.h>
 31 #include <linux/errno.h>
 32 #include <linux/unistd.h>
 33 #include <linux/sunrpc/clnt.h>
 34 #include <linux/sunrpc/addr.h>
 35 #include <linux/sunrpc/stats.h>
 36 #include <linux/sunrpc/metrics.h>
 37 #include <linux/sunrpc/xprtsock.h>
 38 #include <linux/sunrpc/xprtrdma.h>
 39 #include <linux/nfs_fs.h>
 40 #include <linux/nfs_mount.h>
 41 #include <linux/nfs4_mount.h>
 42 #include <linux/lockd/bind.h>
 43 #include <linux/seq_file.h>
 44 #include <linux/mount.h>
 45 #include <linux/namei.h>
 46 #include <linux/vfs.h>
 47 #include <linux/inet.h>
 48 #include <linux/in6.h>
 49 #include <linux/slab.h>
 50 #include <net/ipv6.h>
 51 #include <linux/netdevice.h>
 52 #include <linux/nfs_xdr.h>
 53 #include <linux/magic.h>
 54 #include <linux/parser.h>
 55 #include <linux/nsproxy.h>
 56 #include <linux/rcupdate.h>
 57 
 58 #include <asm/uaccess.h>
 59 
 60 #include "nfs4_fs.h"
 61 #include "callback.h"
 62 #include "delegation.h"
 63 #include "iostat.h"
 64 #include "internal.h"
 65 #include "fscache.h"
 66 #include "nfs4session.h"
 67 #include "pnfs.h"
 68 #include "nfs.h"
 69 
 70 #define NFSDBG_FACILITY         NFSDBG_VFS
 71 #define NFS_TEXT_DATA           1
 72 
 73 #if IS_ENABLED(CONFIG_NFS_V3)
 74 #define NFS_DEFAULT_VERSION 3
 75 #else
 76 #define NFS_DEFAULT_VERSION 2
 77 #endif
 78 
 79 enum {
 80         /* Mount options that take no arguments */
 81         Opt_soft, Opt_hard,
 82         Opt_posix, Opt_noposix,
 83         Opt_cto, Opt_nocto,
 84         Opt_ac, Opt_noac,
 85         Opt_lock, Opt_nolock,
 86         Opt_udp, Opt_tcp, Opt_rdma,
 87         Opt_acl, Opt_noacl,
 88         Opt_rdirplus, Opt_nordirplus,
 89         Opt_sharecache, Opt_nosharecache,
 90         Opt_resvport, Opt_noresvport,
 91         Opt_fscache, Opt_nofscache,
 92         Opt_migration, Opt_nomigration,
 93 
 94         /* Mount options that take integer arguments */
 95         Opt_port,
 96         Opt_rsize, Opt_wsize, Opt_bsize,
 97         Opt_timeo, Opt_retrans,
 98         Opt_acregmin, Opt_acregmax,
 99         Opt_acdirmin, Opt_acdirmax,
100         Opt_actimeo,
101         Opt_namelen,
102         Opt_mountport,
103         Opt_mountvers,
104         Opt_minorversion,
105 
106         /* Mount options that take string arguments */
107         Opt_nfsvers,
108         Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
109         Opt_addr, Opt_mountaddr, Opt_clientaddr,
110         Opt_lookupcache,
111         Opt_fscache_uniq,
112         Opt_local_lock,
113 
114         /* Special mount options */
115         Opt_userspace, Opt_deprecated, Opt_sloppy,
116 
117         Opt_err
118 };
119 
120 static const match_table_t nfs_mount_option_tokens = {
121         { Opt_userspace, "bg" },
122         { Opt_userspace, "fg" },
123         { Opt_userspace, "retry=%s" },
124 
125         { Opt_sloppy, "sloppy" },
126 
127         { Opt_soft, "soft" },
128         { Opt_hard, "hard" },
129         { Opt_deprecated, "intr" },
130         { Opt_deprecated, "nointr" },
131         { Opt_posix, "posix" },
132         { Opt_noposix, "noposix" },
133         { Opt_cto, "cto" },
134         { Opt_nocto, "nocto" },
135         { Opt_ac, "ac" },
136         { Opt_noac, "noac" },
137         { Opt_lock, "lock" },
138         { Opt_nolock, "nolock" },
139         { Opt_udp, "udp" },
140         { Opt_tcp, "tcp" },
141         { Opt_rdma, "rdma" },
142         { Opt_acl, "acl" },
143         { Opt_noacl, "noacl" },
144         { Opt_rdirplus, "rdirplus" },
145         { Opt_nordirplus, "nordirplus" },
146         { Opt_sharecache, "sharecache" },
147         { Opt_nosharecache, "nosharecache" },
148         { Opt_resvport, "resvport" },
149         { Opt_noresvport, "noresvport" },
150         { Opt_fscache, "fsc" },
151         { Opt_nofscache, "nofsc" },
152         { Opt_migration, "migration" },
153         { Opt_nomigration, "nomigration" },
154 
155         { Opt_port, "port=%s" },
156         { Opt_rsize, "rsize=%s" },
157         { Opt_wsize, "wsize=%s" },
158         { Opt_bsize, "bsize=%s" },
159         { Opt_timeo, "timeo=%s" },
160         { Opt_retrans, "retrans=%s" },
161         { Opt_acregmin, "acregmin=%s" },
162         { Opt_acregmax, "acregmax=%s" },
163         { Opt_acdirmin, "acdirmin=%s" },
164         { Opt_acdirmax, "acdirmax=%s" },
165         { Opt_actimeo, "actimeo=%s" },
166         { Opt_namelen, "namlen=%s" },
167         { Opt_mountport, "mountport=%s" },
168         { Opt_mountvers, "mountvers=%s" },
169         { Opt_minorversion, "minorversion=%s" },
170 
171         { Opt_nfsvers, "nfsvers=%s" },
172         { Opt_nfsvers, "vers=%s" },
173 
174         { Opt_sec, "sec=%s" },
175         { Opt_proto, "proto=%s" },
176         { Opt_mountproto, "mountproto=%s" },
177         { Opt_addr, "addr=%s" },
178         { Opt_clientaddr, "clientaddr=%s" },
179         { Opt_mounthost, "mounthost=%s" },
180         { Opt_mountaddr, "mountaddr=%s" },
181 
182         { Opt_lookupcache, "lookupcache=%s" },
183         { Opt_fscache_uniq, "fsc=%s" },
184         { Opt_local_lock, "local_lock=%s" },
185 
186         /* The following needs to be listed after all other options */
187         { Opt_nfsvers, "v%s" },
188 
189         { Opt_err, NULL }
190 };
191 
192 enum {
193         Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
194         Opt_xprt_rdma6,
195 
196         Opt_xprt_err
197 };
198 
199 static const match_table_t nfs_xprt_protocol_tokens = {
200         { Opt_xprt_udp, "udp" },
201         { Opt_xprt_udp6, "udp6" },
202         { Opt_xprt_tcp, "tcp" },
203         { Opt_xprt_tcp6, "tcp6" },
204         { Opt_xprt_rdma, "rdma" },
205         { Opt_xprt_rdma6, "rdma6" },
206 
207         { Opt_xprt_err, NULL }
208 };
209 
210 enum {
211         Opt_sec_none, Opt_sec_sys,
212         Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
213         Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
214         Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
215 
216         Opt_sec_err
217 };
218 
219 static const match_table_t nfs_secflavor_tokens = {
220         { Opt_sec_none, "none" },
221         { Opt_sec_none, "null" },
222         { Opt_sec_sys, "sys" },
223 
224         { Opt_sec_krb5, "krb5" },
225         { Opt_sec_krb5i, "krb5i" },
226         { Opt_sec_krb5p, "krb5p" },
227 
228         { Opt_sec_lkey, "lkey" },
229         { Opt_sec_lkeyi, "lkeyi" },
230         { Opt_sec_lkeyp, "lkeyp" },
231 
232         { Opt_sec_spkm, "spkm3" },
233         { Opt_sec_spkmi, "spkm3i" },
234         { Opt_sec_spkmp, "spkm3p" },
235 
236         { Opt_sec_err, NULL }
237 };
238 
239 enum {
240         Opt_lookupcache_all, Opt_lookupcache_positive,
241         Opt_lookupcache_none,
242 
243         Opt_lookupcache_err
244 };
245 
246 static match_table_t nfs_lookupcache_tokens = {
247         { Opt_lookupcache_all, "all" },
248         { Opt_lookupcache_positive, "pos" },
249         { Opt_lookupcache_positive, "positive" },
250         { Opt_lookupcache_none, "none" },
251 
252         { Opt_lookupcache_err, NULL }
253 };
254 
255 enum {
256         Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
257         Opt_local_lock_none,
258 
259         Opt_local_lock_err
260 };
261 
262 static match_table_t nfs_local_lock_tokens = {
263         { Opt_local_lock_all, "all" },
264         { Opt_local_lock_flock, "flock" },
265         { Opt_local_lock_posix, "posix" },
266         { Opt_local_lock_none, "none" },
267 
268         { Opt_local_lock_err, NULL }
269 };
270 
271 enum {
272         Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
273         Opt_vers_4_1, Opt_vers_4_2,
274 
275         Opt_vers_err
276 };
277 
278 static match_table_t nfs_vers_tokens = {
279         { Opt_vers_2, "2" },
280         { Opt_vers_3, "3" },
281         { Opt_vers_4, "4" },
282         { Opt_vers_4_0, "4.0" },
283         { Opt_vers_4_1, "4.1" },
284         { Opt_vers_4_2, "4.2" },
285 
286         { Opt_vers_err, NULL }
287 };
288 
289 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
290                 int flags, const char *dev_name, void *raw_data);
291 
292 struct file_system_type nfs_fs_type = {
293         .owner          = THIS_MODULE,
294         .name           = "nfs",
295         .mount          = nfs_fs_mount,
296         .kill_sb        = nfs_kill_super,
297         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
298 };
299 MODULE_ALIAS_FS("nfs");
300 EXPORT_SYMBOL_GPL(nfs_fs_type);
301 
302 struct file_system_type nfs_xdev_fs_type = {
303         .owner          = THIS_MODULE,
304         .name           = "nfs",
305         .mount          = nfs_xdev_mount,
306         .kill_sb        = nfs_kill_super,
307         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
308 };
309 
310 const struct super_operations nfs_sops = {
311         .alloc_inode    = nfs_alloc_inode,
312         .destroy_inode  = nfs_destroy_inode,
313         .write_inode    = nfs_write_inode,
314         .drop_inode     = nfs_drop_inode,
315         .statfs         = nfs_statfs,
316         .evict_inode    = nfs_evict_inode,
317         .umount_begin   = nfs_umount_begin,
318         .show_options   = nfs_show_options,
319         .show_devname   = nfs_show_devname,
320         .show_path      = nfs_show_path,
321         .show_stats     = nfs_show_stats,
322         .remount_fs     = nfs_remount,
323 };
324 EXPORT_SYMBOL_GPL(nfs_sops);
325 
326 #if IS_ENABLED(CONFIG_NFS_V4)
327 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
328 static int nfs4_validate_mount_data(void *options,
329         struct nfs_parsed_mount_data *args, const char *dev_name);
330 
331 struct file_system_type nfs4_fs_type = {
332         .owner          = THIS_MODULE,
333         .name           = "nfs4",
334         .mount          = nfs_fs_mount,
335         .kill_sb        = nfs_kill_super,
336         .fs_flags       = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
337 };
338 MODULE_ALIAS_FS("nfs4");
339 MODULE_ALIAS("nfs4");
340 EXPORT_SYMBOL_GPL(nfs4_fs_type);
341 
342 static int __init register_nfs4_fs(void)
343 {
344         return register_filesystem(&nfs4_fs_type);
345 }
346 
347 static void unregister_nfs4_fs(void)
348 {
349         unregister_filesystem(&nfs4_fs_type);
350 }
351 #else
352 static int __init register_nfs4_fs(void)
353 {
354         return 0;
355 }
356 
357 static void unregister_nfs4_fs(void)
358 {
359 }
360 #endif
361 
362 static struct shrinker acl_shrinker = {
363         .count_objects  = nfs_access_cache_count,
364         .scan_objects   = nfs_access_cache_scan,
365         .seeks          = DEFAULT_SEEKS,
366 };
367 
368 /*
369  * Register the NFS filesystems
370  */
371 int __init register_nfs_fs(void)
372 {
373         int ret;
374 
375         ret = register_filesystem(&nfs_fs_type);
376         if (ret < 0)
377                 goto error_0;
378 
379         ret = register_nfs4_fs();
380         if (ret < 0)
381                 goto error_1;
382 
383         ret = nfs_register_sysctl();
384         if (ret < 0)
385                 goto error_2;
386         ret = register_shrinker(&acl_shrinker);
387         if (ret < 0)
388                 goto error_3;
389         return 0;
390 error_3:
391         nfs_unregister_sysctl();
392 error_2:
393         unregister_nfs4_fs();
394 error_1:
395         unregister_filesystem(&nfs_fs_type);
396 error_0:
397         return ret;
398 }
399 
400 /*
401  * Unregister the NFS filesystems
402  */
403 void __exit unregister_nfs_fs(void)
404 {
405         unregister_shrinker(&acl_shrinker);
406         nfs_unregister_sysctl();
407         unregister_nfs4_fs();
408         unregister_filesystem(&nfs_fs_type);
409 }
410 
411 bool nfs_sb_active(struct super_block *sb)
412 {
413         struct nfs_server *server = NFS_SB(sb);
414 
415         if (!atomic_inc_not_zero(&sb->s_active))
416                 return false;
417         if (atomic_inc_return(&server->active) != 1)
418                 atomic_dec(&sb->s_active);
419         return true;
420 }
421 EXPORT_SYMBOL_GPL(nfs_sb_active);
422 
423 void nfs_sb_deactive(struct super_block *sb)
424 {
425         struct nfs_server *server = NFS_SB(sb);
426 
427         if (atomic_dec_and_test(&server->active))
428                 deactivate_super(sb);
429 }
430 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
431 
432 /*
433  * Deliver file system statistics to userspace
434  */
435 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
436 {
437         struct nfs_server *server = NFS_SB(dentry->d_sb);
438         unsigned char blockbits;
439         unsigned long blockres;
440         struct nfs_fh *fh = NFS_FH(d_inode(dentry));
441         struct nfs_fsstat res;
442         int error = -ENOMEM;
443 
444         res.fattr = nfs_alloc_fattr();
445         if (res.fattr == NULL)
446                 goto out_err;
447 
448         error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
449         if (unlikely(error == -ESTALE)) {
450                 struct dentry *pd_dentry;
451 
452                 pd_dentry = dget_parent(dentry);
453                 if (pd_dentry != NULL) {
454                         nfs_zap_caches(d_inode(pd_dentry));
455                         dput(pd_dentry);
456                 }
457         }
458         nfs_free_fattr(res.fattr);
459         if (error < 0)
460                 goto out_err;
461 
462         buf->f_type = NFS_SUPER_MAGIC;
463 
464         /*
465          * Current versions of glibc do not correctly handle the
466          * case where f_frsize != f_bsize.  Eventually we want to
467          * report the value of wtmult in this field.
468          */
469         buf->f_frsize = dentry->d_sb->s_blocksize;
470 
471         /*
472          * On most *nix systems, f_blocks, f_bfree, and f_bavail
473          * are reported in units of f_frsize.  Linux hasn't had
474          * an f_frsize field in its statfs struct until recently,
475          * thus historically Linux's sys_statfs reports these
476          * fields in units of f_bsize.
477          */
478         buf->f_bsize = dentry->d_sb->s_blocksize;
479         blockbits = dentry->d_sb->s_blocksize_bits;
480         blockres = (1 << blockbits) - 1;
481         buf->f_blocks = (res.tbytes + blockres) >> blockbits;
482         buf->f_bfree = (res.fbytes + blockres) >> blockbits;
483         buf->f_bavail = (res.abytes + blockres) >> blockbits;
484 
485         buf->f_files = res.tfiles;
486         buf->f_ffree = res.afiles;
487 
488         buf->f_namelen = server->namelen;
489 
490         return 0;
491 
492  out_err:
493         dprintk("%s: statfs error = %d\n", __func__, -error);
494         return error;
495 }
496 EXPORT_SYMBOL_GPL(nfs_statfs);
497 
498 /*
499  * Map the security flavour number to a name
500  */
501 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
502 {
503         static const struct {
504                 rpc_authflavor_t flavour;
505                 const char *str;
506         } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
507                 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
508                 { RPC_AUTH_NULL, "null" },
509                 { RPC_AUTH_UNIX, "sys" },
510                 { RPC_AUTH_GSS_KRB5, "krb5" },
511                 { RPC_AUTH_GSS_KRB5I, "krb5i" },
512                 { RPC_AUTH_GSS_KRB5P, "krb5p" },
513                 { RPC_AUTH_GSS_LKEY, "lkey" },
514                 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
515                 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
516                 { RPC_AUTH_GSS_SPKM, "spkm" },
517                 { RPC_AUTH_GSS_SPKMI, "spkmi" },
518                 { RPC_AUTH_GSS_SPKMP, "spkmp" },
519                 { UINT_MAX, "unknown" }
520         };
521         int i;
522 
523         for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
524                 if (sec_flavours[i].flavour == flavour)
525                         break;
526         }
527         return sec_flavours[i].str;
528 }
529 
530 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
531                                   int showdefaults)
532 {
533         struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
534 
535         seq_printf(m, ",mountproto=");
536         switch (sap->sa_family) {
537         case AF_INET:
538                 switch (nfss->mountd_protocol) {
539                 case IPPROTO_UDP:
540                         seq_printf(m, RPCBIND_NETID_UDP);
541                         break;
542                 case IPPROTO_TCP:
543                         seq_printf(m, RPCBIND_NETID_TCP);
544                         break;
545                 default:
546                         if (showdefaults)
547                                 seq_printf(m, "auto");
548                 }
549                 break;
550         case AF_INET6:
551                 switch (nfss->mountd_protocol) {
552                 case IPPROTO_UDP:
553                         seq_printf(m, RPCBIND_NETID_UDP6);
554                         break;
555                 case IPPROTO_TCP:
556                         seq_printf(m, RPCBIND_NETID_TCP6);
557                         break;
558                 default:
559                         if (showdefaults)
560                                 seq_printf(m, "auto");
561                 }
562                 break;
563         default:
564                 if (showdefaults)
565                         seq_printf(m, "auto");
566         }
567 }
568 
569 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
570                                     int showdefaults)
571 {
572         struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
573 
574         if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
575                 return;
576 
577         switch (sap->sa_family) {
578         case AF_INET: {
579                 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
580                 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
581                 break;
582         }
583         case AF_INET6: {
584                 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
585                 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
586                 break;
587         }
588         default:
589                 if (showdefaults)
590                         seq_printf(m, ",mountaddr=unspecified");
591         }
592 
593         if (nfss->mountd_version || showdefaults)
594                 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
595         if ((nfss->mountd_port &&
596                 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
597                 showdefaults)
598                 seq_printf(m, ",mountport=%u", nfss->mountd_port);
599 
600         nfs_show_mountd_netid(m, nfss, showdefaults);
601 }
602 
603 #if IS_ENABLED(CONFIG_NFS_V4)
604 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
605                                     int showdefaults)
606 {
607         struct nfs_client *clp = nfss->nfs_client;
608 
609         seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
610 }
611 #else
612 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
613                                     int showdefaults)
614 {
615 }
616 #endif
617 
618 static void nfs_show_nfs_version(struct seq_file *m,
619                 unsigned int version,
620                 unsigned int minorversion)
621 {
622         seq_printf(m, ",vers=%u", version);
623         if (version == 4)
624                 seq_printf(m, ".%u", minorversion);
625 }
626 
627 /*
628  * Describe the mount options in force on this server representation
629  */
630 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
631                                    int showdefaults)
632 {
633         static const struct proc_nfs_info {
634                 int flag;
635                 const char *str;
636                 const char *nostr;
637         } nfs_info[] = {
638                 { NFS_MOUNT_SOFT, ",soft", ",hard" },
639                 { NFS_MOUNT_POSIX, ",posix", "" },
640                 { NFS_MOUNT_NOCTO, ",nocto", "" },
641                 { NFS_MOUNT_NOAC, ",noac", "" },
642                 { NFS_MOUNT_NONLM, ",nolock", "" },
643                 { NFS_MOUNT_NOACL, ",noacl", "" },
644                 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
645                 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
646                 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
647                 { 0, NULL, NULL }
648         };
649         const struct proc_nfs_info *nfs_infop;
650         struct nfs_client *clp = nfss->nfs_client;
651         u32 version = clp->rpc_ops->version;
652         int local_flock, local_fcntl;
653 
654         nfs_show_nfs_version(m, version, clp->cl_minorversion);
655         seq_printf(m, ",rsize=%u", nfss->rsize);
656         seq_printf(m, ",wsize=%u", nfss->wsize);
657         if (nfss->bsize != 0)
658                 seq_printf(m, ",bsize=%u", nfss->bsize);
659         seq_printf(m, ",namlen=%u", nfss->namelen);
660         if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
661                 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
662         if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
663                 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
664         if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
665                 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
666         if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
667                 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
668         for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
669                 if (nfss->flags & nfs_infop->flag)
670                         seq_puts(m, nfs_infop->str);
671                 else
672                         seq_puts(m, nfs_infop->nostr);
673         }
674         rcu_read_lock();
675         seq_printf(m, ",proto=%s",
676                    rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
677         rcu_read_unlock();
678         if (version == 4) {
679                 if (nfss->port != NFS_PORT)
680                         seq_printf(m, ",port=%u", nfss->port);
681         } else
682                 if (nfss->port)
683                         seq_printf(m, ",port=%u", nfss->port);
684 
685         seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
686         seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
687         seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
688 
689         if (version != 4)
690                 nfs_show_mountd_options(m, nfss, showdefaults);
691         else
692                 nfs_show_nfsv4_options(m, nfss, showdefaults);
693 
694         if (nfss->options & NFS_OPTION_FSCACHE)
695                 seq_printf(m, ",fsc");
696 
697         if (nfss->options & NFS_OPTION_MIGRATION)
698                 seq_printf(m, ",migration");
699 
700         if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
701                 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
702                         seq_printf(m, ",lookupcache=none");
703                 else
704                         seq_printf(m, ",lookupcache=pos");
705         }
706 
707         local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
708         local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
709 
710         if (!local_flock && !local_fcntl)
711                 seq_printf(m, ",local_lock=none");
712         else if (local_flock && local_fcntl)
713                 seq_printf(m, ",local_lock=all");
714         else if (local_flock)
715                 seq_printf(m, ",local_lock=flock");
716         else
717                 seq_printf(m, ",local_lock=posix");
718 }
719 
720 /*
721  * Describe the mount options on this VFS mountpoint
722  */
723 int nfs_show_options(struct seq_file *m, struct dentry *root)
724 {
725         struct nfs_server *nfss = NFS_SB(root->d_sb);
726 
727         nfs_show_mount_options(m, nfss, 0);
728 
729         rcu_read_lock();
730         seq_printf(m, ",addr=%s",
731                         rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
732                                                         RPC_DISPLAY_ADDR));
733         rcu_read_unlock();
734 
735         return 0;
736 }
737 EXPORT_SYMBOL_GPL(nfs_show_options);
738 
739 #if IS_ENABLED(CONFIG_NFS_V4)
740 #ifdef CONFIG_NFS_V4_1
741 static void show_sessions(struct seq_file *m, struct nfs_server *server)
742 {
743         if (nfs4_has_session(server->nfs_client))
744                 seq_printf(m, ",sessions");
745 }
746 #else
747 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
748 #endif
749 #endif
750 
751 #ifdef CONFIG_NFS_V4_1
752 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
753 {
754         seq_printf(m, ",pnfs=");
755         if (server->pnfs_curr_ld)
756                 seq_printf(m, "%s", server->pnfs_curr_ld->name);
757         else
758                 seq_printf(m, "not configured");
759 }
760 
761 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
762 {
763         if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
764                 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
765                 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
766                            "date='%llu,%u'",
767                            impl_id->name, impl_id->domain,
768                            impl_id->date.seconds, impl_id->date.nseconds);
769         }
770 }
771 #else
772 #if IS_ENABLED(CONFIG_NFS_V4)
773 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
774 {
775 }
776 #endif
777 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
778 {
779 }
780 #endif
781 
782 int nfs_show_devname(struct seq_file *m, struct dentry *root)
783 {
784         char *page = (char *) __get_free_page(GFP_KERNEL);
785         char *devname, *dummy;
786         int err = 0;
787         if (!page)
788                 return -ENOMEM;
789         devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
790         if (IS_ERR(devname))
791                 err = PTR_ERR(devname);
792         else
793                 seq_escape(m, devname, " \t\n\\");
794         free_page((unsigned long)page);
795         return err;
796 }
797 EXPORT_SYMBOL_GPL(nfs_show_devname);
798 
799 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
800 {
801         seq_puts(m, "/");
802         return 0;
803 }
804 EXPORT_SYMBOL_GPL(nfs_show_path);
805 
806 /*
807  * Present statistical information for this VFS mountpoint
808  */
809 int nfs_show_stats(struct seq_file *m, struct dentry *root)
810 {
811         int i, cpu;
812         struct nfs_server *nfss = NFS_SB(root->d_sb);
813         struct rpc_auth *auth = nfss->client->cl_auth;
814         struct nfs_iostats totals = { };
815 
816         seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
817 
818         /*
819          * Display all mount option settings
820          */
821         seq_printf(m, "\n\topts:\t");
822         seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
823         seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
824         seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
825         seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
826         nfs_show_mount_options(m, nfss, 1);
827 
828         seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
829 
830         show_implementation_id(m, nfss);
831 
832         seq_printf(m, "\n\tcaps:\t");
833         seq_printf(m, "caps=0x%x", nfss->caps);
834         seq_printf(m, ",wtmult=%u", nfss->wtmult);
835         seq_printf(m, ",dtsize=%u", nfss->dtsize);
836         seq_printf(m, ",bsize=%u", nfss->bsize);
837         seq_printf(m, ",namlen=%u", nfss->namelen);
838 
839 #if IS_ENABLED(CONFIG_NFS_V4)
840         if (nfss->nfs_client->rpc_ops->version == 4) {
841                 seq_printf(m, "\n\tnfsv4:\t");
842                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
843                 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
844                 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
845                 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
846                 show_sessions(m, nfss);
847                 show_pnfs(m, nfss);
848         }
849 #endif
850 
851         /*
852          * Display security flavor in effect for this mount
853          */
854         seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
855         if (auth->au_flavor)
856                 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
857 
858         /*
859          * Display superblock I/O counters
860          */
861         for_each_possible_cpu(cpu) {
862                 struct nfs_iostats *stats;
863 
864                 preempt_disable();
865                 stats = per_cpu_ptr(nfss->io_stats, cpu);
866 
867                 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
868                         totals.events[i] += stats->events[i];
869                 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
870                         totals.bytes[i] += stats->bytes[i];
871 #ifdef CONFIG_NFS_FSCACHE
872                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
873                         totals.fscache[i] += stats->fscache[i];
874 #endif
875 
876                 preempt_enable();
877         }
878 
879         seq_printf(m, "\n\tevents:\t");
880         for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
881                 seq_printf(m, "%lu ", totals.events[i]);
882         seq_printf(m, "\n\tbytes:\t");
883         for (i = 0; i < __NFSIOS_BYTESMAX; i++)
884                 seq_printf(m, "%Lu ", totals.bytes[i]);
885 #ifdef CONFIG_NFS_FSCACHE
886         if (nfss->options & NFS_OPTION_FSCACHE) {
887                 seq_printf(m, "\n\tfsc:\t");
888                 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
889                         seq_printf(m, "%Lu ", totals.bytes[i]);
890         }
891 #endif
892         seq_printf(m, "\n");
893 
894         rpc_print_iostats(m, nfss->client);
895 
896         return 0;
897 }
898 EXPORT_SYMBOL_GPL(nfs_show_stats);
899 
900 /*
901  * Begin unmount by attempting to remove all automounted mountpoints we added
902  * in response to xdev traversals and referrals
903  */
904 void nfs_umount_begin(struct super_block *sb)
905 {
906         struct nfs_server *server;
907         struct rpc_clnt *rpc;
908 
909         server = NFS_SB(sb);
910         /* -EIO all pending I/O */
911         rpc = server->client_acl;
912         if (!IS_ERR(rpc))
913                 rpc_killall_tasks(rpc);
914         rpc = server->client;
915         if (!IS_ERR(rpc))
916                 rpc_killall_tasks(rpc);
917 }
918 EXPORT_SYMBOL_GPL(nfs_umount_begin);
919 
920 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
921 {
922         struct nfs_parsed_mount_data *data;
923 
924         data = kzalloc(sizeof(*data), GFP_KERNEL);
925         if (data) {
926                 data->acregmin          = NFS_DEF_ACREGMIN;
927                 data->acregmax          = NFS_DEF_ACREGMAX;
928                 data->acdirmin          = NFS_DEF_ACDIRMIN;
929                 data->acdirmax          = NFS_DEF_ACDIRMAX;
930                 data->mount_server.port = NFS_UNSPEC_PORT;
931                 data->nfs_server.port   = NFS_UNSPEC_PORT;
932                 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
933                 data->selected_flavor   = RPC_AUTH_MAXFLAVOR;
934                 data->minorversion      = 0;
935                 data->need_mount        = true;
936                 data->net               = current->nsproxy->net_ns;
937                 security_init_mnt_opts(&data->lsm_opts);
938         }
939         return data;
940 }
941 
942 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
943 {
944         if (data) {
945                 kfree(data->client_address);
946                 kfree(data->mount_server.hostname);
947                 kfree(data->nfs_server.export_path);
948                 kfree(data->nfs_server.hostname);
949                 kfree(data->fscache_uniq);
950                 security_free_mnt_opts(&data->lsm_opts);
951                 kfree(data);
952         }
953 }
954 
955 /*
956  * Sanity-check a server address provided by the mount command.
957  *
958  * Address family must be initialized, and address must not be
959  * the ANY address for that family.
960  */
961 static int nfs_verify_server_address(struct sockaddr *addr)
962 {
963         switch (addr->sa_family) {
964         case AF_INET: {
965                 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
966                 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
967         }
968         case AF_INET6: {
969                 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
970                 return !ipv6_addr_any(sa);
971         }
972         }
973 
974         dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
975         return 0;
976 }
977 
978 /*
979  * Select between a default port value and a user-specified port value.
980  * If a zero value is set, then autobind will be used.
981  */
982 static void nfs_set_port(struct sockaddr *sap, int *port,
983                                  const unsigned short default_port)
984 {
985         if (*port == NFS_UNSPEC_PORT)
986                 *port = default_port;
987 
988         rpc_set_port(sap, *port);
989 }
990 
991 /*
992  * Sanity check the NFS transport protocol.
993  *
994  */
995 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
996 {
997         switch (mnt->nfs_server.protocol) {
998         case XPRT_TRANSPORT_UDP:
999         case XPRT_TRANSPORT_TCP:
1000         case XPRT_TRANSPORT_RDMA:
1001                 break;
1002         default:
1003                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1004         }
1005 }
1006 
1007 /*
1008  * For text based NFSv2/v3 mounts, the mount protocol transport default
1009  * settings should depend upon the specified NFS transport.
1010  */
1011 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1012 {
1013         nfs_validate_transport_protocol(mnt);
1014 
1015         if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1016             mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1017                         return;
1018         switch (mnt->nfs_server.protocol) {
1019         case XPRT_TRANSPORT_UDP:
1020                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1021                 break;
1022         case XPRT_TRANSPORT_TCP:
1023         case XPRT_TRANSPORT_RDMA:
1024                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1025         }
1026 }
1027 
1028 /*
1029  * Add 'flavor' to 'auth_info' if not already present.
1030  * Returns true if 'flavor' ends up in the list, false otherwise
1031  */
1032 static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
1033                               rpc_authflavor_t flavor)
1034 {
1035         unsigned int i;
1036         unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
1037 
1038         /* make sure this flavor isn't already in the list */
1039         for (i = 0; i < auth_info->flavor_len; i++) {
1040                 if (flavor == auth_info->flavors[i])
1041                         return true;
1042         }
1043 
1044         if (auth_info->flavor_len + 1 >= max_flavor_len) {
1045                 dfprintk(MOUNT, "NFS: too many sec= flavors\n");
1046                 return false;
1047         }
1048 
1049         auth_info->flavors[auth_info->flavor_len++] = flavor;
1050         return true;
1051 }
1052 
1053 /*
1054  * Return true if 'match' is in auth_info or auth_info is empty.
1055  * Return false otherwise.
1056  */
1057 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
1058                          rpc_authflavor_t match)
1059 {
1060         int i;
1061 
1062         if (!auth_info->flavor_len)
1063                 return true;
1064 
1065         for (i = 0; i < auth_info->flavor_len; i++) {
1066                 if (auth_info->flavors[i] == match)
1067                         return true;
1068         }
1069         return false;
1070 }
1071 EXPORT_SYMBOL_GPL(nfs_auth_info_match);
1072 
1073 /*
1074  * Parse the value of the 'sec=' option.
1075  */
1076 static int nfs_parse_security_flavors(char *value,
1077                                       struct nfs_parsed_mount_data *mnt)
1078 {
1079         substring_t args[MAX_OPT_ARGS];
1080         rpc_authflavor_t pseudoflavor;
1081         char *p;
1082 
1083         dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1084 
1085         while ((p = strsep(&value, ":")) != NULL) {
1086                 switch (match_token(p, nfs_secflavor_tokens, args)) {
1087                 case Opt_sec_none:
1088                         pseudoflavor = RPC_AUTH_NULL;
1089                         break;
1090                 case Opt_sec_sys:
1091                         pseudoflavor = RPC_AUTH_UNIX;
1092                         break;
1093                 case Opt_sec_krb5:
1094                         pseudoflavor = RPC_AUTH_GSS_KRB5;
1095                         break;
1096                 case Opt_sec_krb5i:
1097                         pseudoflavor = RPC_AUTH_GSS_KRB5I;
1098                         break;
1099                 case Opt_sec_krb5p:
1100                         pseudoflavor = RPC_AUTH_GSS_KRB5P;
1101                         break;
1102                 case Opt_sec_lkey:
1103                         pseudoflavor = RPC_AUTH_GSS_LKEY;
1104                         break;
1105                 case Opt_sec_lkeyi:
1106                         pseudoflavor = RPC_AUTH_GSS_LKEYI;
1107                         break;
1108                 case Opt_sec_lkeyp:
1109                         pseudoflavor = RPC_AUTH_GSS_LKEYP;
1110                         break;
1111                 case Opt_sec_spkm:
1112                         pseudoflavor = RPC_AUTH_GSS_SPKM;
1113                         break;
1114                 case Opt_sec_spkmi:
1115                         pseudoflavor = RPC_AUTH_GSS_SPKMI;
1116                         break;
1117                 case Opt_sec_spkmp:
1118                         pseudoflavor = RPC_AUTH_GSS_SPKMP;
1119                         break;
1120                 default:
1121                         dfprintk(MOUNT,
1122                                  "NFS: sec= option '%s' not recognized\n", p);
1123                         return 0;
1124                 }
1125 
1126                 if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
1127                         return 0;
1128         }
1129 
1130         return 1;
1131 }
1132 
1133 static int nfs_parse_version_string(char *string,
1134                 struct nfs_parsed_mount_data *mnt,
1135                 substring_t *args)
1136 {
1137         mnt->flags &= ~NFS_MOUNT_VER3;
1138         switch (match_token(string, nfs_vers_tokens, args)) {
1139         case Opt_vers_2:
1140                 mnt->version = 2;
1141                 break;
1142         case Opt_vers_3:
1143                 mnt->flags |= NFS_MOUNT_VER3;
1144                 mnt->version = 3;
1145                 break;
1146         case Opt_vers_4:
1147                 /* Backward compatibility option. In future,
1148                  * the mount program should always supply
1149                  * a NFSv4 minor version number.
1150                  */
1151                 mnt->version = 4;
1152                 break;
1153         case Opt_vers_4_0:
1154                 mnt->version = 4;
1155                 mnt->minorversion = 0;
1156                 break;
1157         case Opt_vers_4_1:
1158                 mnt->version = 4;
1159                 mnt->minorversion = 1;
1160                 break;
1161         case Opt_vers_4_2:
1162                 mnt->version = 4;
1163                 mnt->minorversion = 2;
1164                 break;
1165         default:
1166                 return 0;
1167         }
1168         return 1;
1169 }
1170 
1171 static int nfs_get_option_str(substring_t args[], char **option)
1172 {
1173         kfree(*option);
1174         *option = match_strdup(args);
1175         return !*option;
1176 }
1177 
1178 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1179 {
1180         int rc;
1181         char *string;
1182 
1183         string = match_strdup(args);
1184         if (string == NULL)
1185                 return -ENOMEM;
1186         rc = kstrtoul(string, 10, option);
1187         kfree(string);
1188 
1189         return rc;
1190 }
1191 
1192 /*
1193  * Error-check and convert a string of mount options from user space into
1194  * a data structure.  The whole mount string is processed; bad options are
1195  * skipped as they are encountered.  If there were no errors, return 1;
1196  * otherwise return 0 (zero).
1197  */
1198 static int nfs_parse_mount_options(char *raw,
1199                                    struct nfs_parsed_mount_data *mnt)
1200 {
1201         char *p, *string, *secdata;
1202         int rc, sloppy = 0, invalid_option = 0;
1203         unsigned short protofamily = AF_UNSPEC;
1204         unsigned short mountfamily = AF_UNSPEC;
1205 
1206         if (!raw) {
1207                 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1208                 return 1;
1209         }
1210         dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1211 
1212         secdata = alloc_secdata();
1213         if (!secdata)
1214                 goto out_nomem;
1215 
1216         rc = security_sb_copy_data(raw, secdata);
1217         if (rc)
1218                 goto out_security_failure;
1219 
1220         rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1221         if (rc)
1222                 goto out_security_failure;
1223 
1224         free_secdata(secdata);
1225 
1226         while ((p = strsep(&raw, ",")) != NULL) {
1227                 substring_t args[MAX_OPT_ARGS];
1228                 unsigned long option;
1229                 int token;
1230 
1231                 if (!*p)
1232                         continue;
1233 
1234                 dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1235 
1236                 token = match_token(p, nfs_mount_option_tokens, args);
1237                 switch (token) {
1238 
1239                 /*
1240                  * boolean options:  foo/nofoo
1241                  */
1242                 case Opt_soft:
1243                         mnt->flags |= NFS_MOUNT_SOFT;
1244                         break;
1245                 case Opt_hard:
1246                         mnt->flags &= ~NFS_MOUNT_SOFT;
1247                         break;
1248                 case Opt_posix:
1249                         mnt->flags |= NFS_MOUNT_POSIX;
1250                         break;
1251                 case Opt_noposix:
1252                         mnt->flags &= ~NFS_MOUNT_POSIX;
1253                         break;
1254                 case Opt_cto:
1255                         mnt->flags &= ~NFS_MOUNT_NOCTO;
1256                         break;
1257                 case Opt_nocto:
1258                         mnt->flags |= NFS_MOUNT_NOCTO;
1259                         break;
1260                 case Opt_ac:
1261                         mnt->flags &= ~NFS_MOUNT_NOAC;
1262                         break;
1263                 case Opt_noac:
1264                         mnt->flags |= NFS_MOUNT_NOAC;
1265                         break;
1266                 case Opt_lock:
1267                         mnt->flags &= ~NFS_MOUNT_NONLM;
1268                         mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1269                                         NFS_MOUNT_LOCAL_FCNTL);
1270                         break;
1271                 case Opt_nolock:
1272                         mnt->flags |= NFS_MOUNT_NONLM;
1273                         mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1274                                        NFS_MOUNT_LOCAL_FCNTL);
1275                         break;
1276                 case Opt_udp:
1277                         mnt->flags &= ~NFS_MOUNT_TCP;
1278                         mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1279                         break;
1280                 case Opt_tcp:
1281                         mnt->flags |= NFS_MOUNT_TCP;
1282                         mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1283                         break;
1284                 case Opt_rdma:
1285                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1286                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1287                         xprt_load_transport(p);
1288                         break;
1289                 case Opt_acl:
1290                         mnt->flags &= ~NFS_MOUNT_NOACL;
1291                         break;
1292                 case Opt_noacl:
1293                         mnt->flags |= NFS_MOUNT_NOACL;
1294                         break;
1295                 case Opt_rdirplus:
1296                         mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1297                         break;
1298                 case Opt_nordirplus:
1299                         mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1300                         break;
1301                 case Opt_sharecache:
1302                         mnt->flags &= ~NFS_MOUNT_UNSHARED;
1303                         break;
1304                 case Opt_nosharecache:
1305                         mnt->flags |= NFS_MOUNT_UNSHARED;
1306                         break;
1307                 case Opt_resvport:
1308                         mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1309                         break;
1310                 case Opt_noresvport:
1311                         mnt->flags |= NFS_MOUNT_NORESVPORT;
1312                         break;
1313                 case Opt_fscache:
1314                         mnt->options |= NFS_OPTION_FSCACHE;
1315                         kfree(mnt->fscache_uniq);
1316                         mnt->fscache_uniq = NULL;
1317                         break;
1318                 case Opt_nofscache:
1319                         mnt->options &= ~NFS_OPTION_FSCACHE;
1320                         kfree(mnt->fscache_uniq);
1321                         mnt->fscache_uniq = NULL;
1322                         break;
1323                 case Opt_migration:
1324                         mnt->options |= NFS_OPTION_MIGRATION;
1325                         break;
1326                 case Opt_nomigration:
1327                         mnt->options &= NFS_OPTION_MIGRATION;
1328                         break;
1329 
1330                 /*
1331                  * options that take numeric values
1332                  */
1333                 case Opt_port:
1334                         if (nfs_get_option_ul(args, &option) ||
1335                             option > USHRT_MAX)
1336                                 goto out_invalid_value;
1337                         mnt->nfs_server.port = option;
1338                         break;
1339                 case Opt_rsize:
1340                         if (nfs_get_option_ul(args, &option))
1341                                 goto out_invalid_value;
1342                         mnt->rsize = option;
1343                         break;
1344                 case Opt_wsize:
1345                         if (nfs_get_option_ul(args, &option))
1346                                 goto out_invalid_value;
1347                         mnt->wsize = option;
1348                         break;
1349                 case Opt_bsize:
1350                         if (nfs_get_option_ul(args, &option))
1351                                 goto out_invalid_value;
1352                         mnt->bsize = option;
1353                         break;
1354                 case Opt_timeo:
1355                         if (nfs_get_option_ul(args, &option) || option == 0)
1356                                 goto out_invalid_value;
1357                         mnt->timeo = option;
1358                         break;
1359                 case Opt_retrans:
1360                         if (nfs_get_option_ul(args, &option) || option == 0)
1361                                 goto out_invalid_value;
1362                         mnt->retrans = option;
1363                         break;
1364                 case Opt_acregmin:
1365                         if (nfs_get_option_ul(args, &option))
1366                                 goto out_invalid_value;
1367                         mnt->acregmin = option;
1368                         break;
1369                 case Opt_acregmax:
1370                         if (nfs_get_option_ul(args, &option))
1371                                 goto out_invalid_value;
1372                         mnt->acregmax = option;
1373                         break;
1374                 case Opt_acdirmin:
1375                         if (nfs_get_option_ul(args, &option))
1376                                 goto out_invalid_value;
1377                         mnt->acdirmin = option;
1378                         break;
1379                 case Opt_acdirmax:
1380                         if (nfs_get_option_ul(args, &option))
1381                                 goto out_invalid_value;
1382                         mnt->acdirmax = option;
1383                         break;
1384                 case Opt_actimeo:
1385                         if (nfs_get_option_ul(args, &option))
1386                                 goto out_invalid_value;
1387                         mnt->acregmin = mnt->acregmax =
1388                         mnt->acdirmin = mnt->acdirmax = option;
1389                         break;
1390                 case Opt_namelen:
1391                         if (nfs_get_option_ul(args, &option))
1392                                 goto out_invalid_value;
1393                         mnt->namlen = option;
1394                         break;
1395                 case Opt_mountport:
1396                         if (nfs_get_option_ul(args, &option) ||
1397                             option > USHRT_MAX)
1398                                 goto out_invalid_value;
1399                         mnt->mount_server.port = option;
1400                         break;
1401                 case Opt_mountvers:
1402                         if (nfs_get_option_ul(args, &option) ||
1403                             option < NFS_MNT_VERSION ||
1404                             option > NFS_MNT3_VERSION)
1405                                 goto out_invalid_value;
1406                         mnt->mount_server.version = option;
1407                         break;
1408                 case Opt_minorversion:
1409                         if (nfs_get_option_ul(args, &option))
1410                                 goto out_invalid_value;
1411                         if (option > NFS4_MAX_MINOR_VERSION)
1412                                 goto out_invalid_value;
1413                         mnt->minorversion = option;
1414                         break;
1415 
1416                 /*
1417                  * options that take text values
1418                  */
1419                 case Opt_nfsvers:
1420                         string = match_strdup(args);
1421                         if (string == NULL)
1422                                 goto out_nomem;
1423                         rc = nfs_parse_version_string(string, mnt, args);
1424                         kfree(string);
1425                         if (!rc)
1426                                 goto out_invalid_value;
1427                         break;
1428                 case Opt_sec:
1429                         string = match_strdup(args);
1430                         if (string == NULL)
1431                                 goto out_nomem;
1432                         rc = nfs_parse_security_flavors(string, mnt);
1433                         kfree(string);
1434                         if (!rc) {
1435                                 dfprintk(MOUNT, "NFS:   unrecognized "
1436                                                 "security flavor\n");
1437                                 return 0;
1438                         }
1439                         break;
1440                 case Opt_proto:
1441                         string = match_strdup(args);
1442                         if (string == NULL)
1443                                 goto out_nomem;
1444                         token = match_token(string,
1445                                             nfs_xprt_protocol_tokens, args);
1446 
1447                         protofamily = AF_INET;
1448                         switch (token) {
1449                         case Opt_xprt_udp6:
1450                                 protofamily = AF_INET6;
1451                         case Opt_xprt_udp:
1452                                 mnt->flags &= ~NFS_MOUNT_TCP;
1453                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1454                                 break;
1455                         case Opt_xprt_tcp6:
1456                                 protofamily = AF_INET6;
1457                         case Opt_xprt_tcp:
1458                                 mnt->flags |= NFS_MOUNT_TCP;
1459                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1460                                 break;
1461                         case Opt_xprt_rdma6:
1462                                 protofamily = AF_INET6;
1463                         case Opt_xprt_rdma:
1464                                 /* vector side protocols to TCP */
1465                                 mnt->flags |= NFS_MOUNT_TCP;
1466                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1467                                 xprt_load_transport(string);
1468                                 break;
1469                         default:
1470                                 dfprintk(MOUNT, "NFS:   unrecognized "
1471                                                 "transport protocol\n");
1472                                 kfree(string);
1473                                 return 0;
1474                         }
1475                         kfree(string);
1476                         break;
1477                 case Opt_mountproto:
1478                         string = match_strdup(args);
1479                         if (string == NULL)
1480                                 goto out_nomem;
1481                         token = match_token(string,
1482                                             nfs_xprt_protocol_tokens, args);
1483                         kfree(string);
1484 
1485                         mountfamily = AF_INET;
1486                         switch (token) {
1487                         case Opt_xprt_udp6:
1488                                 mountfamily = AF_INET6;
1489                         case Opt_xprt_udp:
1490                                 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1491                                 break;
1492                         case Opt_xprt_tcp6:
1493                                 mountfamily = AF_INET6;
1494                         case Opt_xprt_tcp:
1495                                 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1496                                 break;
1497                         case Opt_xprt_rdma: /* not used for side protocols */
1498                         default:
1499                                 dfprintk(MOUNT, "NFS:   unrecognized "
1500                                                 "transport protocol\n");
1501                                 return 0;
1502                         }
1503                         break;
1504                 case Opt_addr:
1505                         string = match_strdup(args);
1506                         if (string == NULL)
1507                                 goto out_nomem;
1508                         mnt->nfs_server.addrlen =
1509                                 rpc_pton(mnt->net, string, strlen(string),
1510                                         (struct sockaddr *)
1511                                         &mnt->nfs_server.address,
1512                                         sizeof(mnt->nfs_server.address));
1513                         kfree(string);
1514                         if (mnt->nfs_server.addrlen == 0)
1515                                 goto out_invalid_address;
1516                         break;
1517                 case Opt_clientaddr:
1518                         if (nfs_get_option_str(args, &mnt->client_address))
1519                                 goto out_nomem;
1520                         break;
1521                 case Opt_mounthost:
1522                         if (nfs_get_option_str(args,
1523                                                &mnt->mount_server.hostname))
1524                                 goto out_nomem;
1525                         break;
1526                 case Opt_mountaddr:
1527                         string = match_strdup(args);
1528                         if (string == NULL)
1529                                 goto out_nomem;
1530                         mnt->mount_server.addrlen =
1531                                 rpc_pton(mnt->net, string, strlen(string),
1532                                         (struct sockaddr *)
1533                                         &mnt->mount_server.address,
1534                                         sizeof(mnt->mount_server.address));
1535                         kfree(string);
1536                         if (mnt->mount_server.addrlen == 0)
1537                                 goto out_invalid_address;
1538                         break;
1539                 case Opt_lookupcache:
1540                         string = match_strdup(args);
1541                         if (string == NULL)
1542                                 goto out_nomem;
1543                         token = match_token(string,
1544                                         nfs_lookupcache_tokens, args);
1545                         kfree(string);
1546                         switch (token) {
1547                                 case Opt_lookupcache_all:
1548                                         mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1549                                         break;
1550                                 case Opt_lookupcache_positive:
1551                                         mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1552                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1553                                         break;
1554                                 case Opt_lookupcache_none:
1555                                         mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1556                                         break;
1557                                 default:
1558                                         dfprintk(MOUNT, "NFS:   invalid "
1559                                                         "lookupcache argument\n");
1560                                         return 0;
1561                         };
1562                         break;
1563                 case Opt_fscache_uniq:
1564                         if (nfs_get_option_str(args, &mnt->fscache_uniq))
1565                                 goto out_nomem;
1566                         mnt->options |= NFS_OPTION_FSCACHE;
1567                         break;
1568                 case Opt_local_lock:
1569                         string = match_strdup(args);
1570                         if (string == NULL)
1571                                 goto out_nomem;
1572                         token = match_token(string, nfs_local_lock_tokens,
1573                                         args);
1574                         kfree(string);
1575                         switch (token) {
1576                         case Opt_local_lock_all:
1577                                 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1578                                                NFS_MOUNT_LOCAL_FCNTL);
1579                                 break;
1580                         case Opt_local_lock_flock:
1581                                 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1582                                 break;
1583                         case Opt_local_lock_posix:
1584                                 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1585                                 break;
1586                         case Opt_local_lock_none:
1587                                 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1588                                                 NFS_MOUNT_LOCAL_FCNTL);
1589                                 break;
1590                         default:
1591                                 dfprintk(MOUNT, "NFS:   invalid "
1592                                                 "local_lock argument\n");
1593                                 return 0;
1594                         };
1595                         break;
1596 
1597                 /*
1598                  * Special options
1599                  */
1600                 case Opt_sloppy:
1601                         sloppy = 1;
1602                         dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1603                         break;
1604                 case Opt_userspace:
1605                 case Opt_deprecated:
1606                         dfprintk(MOUNT, "NFS:   ignoring mount option "
1607                                         "'%s'\n", p);
1608                         break;
1609 
1610                 default:
1611                         invalid_option = 1;
1612                         dfprintk(MOUNT, "NFS:   unrecognized mount option "
1613                                         "'%s'\n", p);
1614                 }
1615         }
1616 
1617         if (!sloppy && invalid_option)
1618                 return 0;
1619 
1620         if (mnt->minorversion && mnt->version != 4)
1621                 goto out_minorversion_mismatch;
1622 
1623         if (mnt->options & NFS_OPTION_MIGRATION &&
1624             (mnt->version != 4 || mnt->minorversion != 0))
1625                 goto out_migration_misuse;
1626 
1627         /*
1628          * verify that any proto=/mountproto= options match the address
1629          * families in the addr=/mountaddr= options.
1630          */
1631         if (protofamily != AF_UNSPEC &&
1632             protofamily != mnt->nfs_server.address.ss_family)
1633                 goto out_proto_mismatch;
1634 
1635         if (mountfamily != AF_UNSPEC) {
1636                 if (mnt->mount_server.addrlen) {
1637                         if (mountfamily != mnt->mount_server.address.ss_family)
1638                                 goto out_mountproto_mismatch;
1639                 } else {
1640                         if (mountfamily != mnt->nfs_server.address.ss_family)
1641                                 goto out_mountproto_mismatch;
1642                 }
1643         }
1644 
1645         return 1;
1646 
1647 out_mountproto_mismatch:
1648         printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1649                          "option\n");
1650         return 0;
1651 out_proto_mismatch:
1652         printk(KERN_INFO "NFS: server address does not match proto= option\n");
1653         return 0;
1654 out_invalid_address:
1655         printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1656         return 0;
1657 out_invalid_value:
1658         printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1659         return 0;
1660 out_minorversion_mismatch:
1661         printk(KERN_INFO "NFS: mount option vers=%u does not support "
1662                          "minorversion=%u\n", mnt->version, mnt->minorversion);
1663         return 0;
1664 out_migration_misuse:
1665         printk(KERN_INFO
1666                 "NFS: 'migration' not supported for this NFS version\n");
1667         return 0;
1668 out_nomem:
1669         printk(KERN_INFO "NFS: not enough memory to parse option\n");
1670         return 0;
1671 out_security_failure:
1672         free_secdata(secdata);
1673         printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1674         return 0;
1675 }
1676 
1677 /*
1678  * Ensure that a specified authtype in args->auth_info is supported by
1679  * the server. Returns 0 and sets args->selected_flavor if it's ok, and
1680  * -EACCES if not.
1681  */
1682 static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
1683                         rpc_authflavor_t *server_authlist, unsigned int count)
1684 {
1685         rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
1686         unsigned int i;
1687 
1688         /*
1689          * If the sec= mount option is used, the specified flavor or AUTH_NULL
1690          * must be in the list returned by the server.
1691          *
1692          * AUTH_NULL has a special meaning when it's in the server list - it
1693          * means that the server will ignore the rpc creds, so any flavor
1694          * can be used.
1695          */
1696         for (i = 0; i < count; i++) {
1697                 flavor = server_authlist[i];
1698 
1699                 if (nfs_auth_info_match(&args->auth_info, flavor) ||
1700                     flavor == RPC_AUTH_NULL)
1701                         goto out;
1702         }
1703 
1704         dfprintk(MOUNT,
1705                  "NFS: specified auth flavors not supported by server\n");
1706         return -EACCES;
1707 
1708 out:
1709         args->selected_flavor = flavor;
1710         dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
1711         return 0;
1712 }
1713 
1714 /*
1715  * Use the remote server's MOUNT service to request the NFS file handle
1716  * corresponding to the provided path.
1717  */
1718 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1719                              struct nfs_fh *root_fh,
1720                              rpc_authflavor_t *server_authlist,
1721                              unsigned int *server_authlist_len)
1722 {
1723         struct nfs_mount_request request = {
1724                 .sap            = (struct sockaddr *)
1725                                                 &args->mount_server.address,
1726                 .dirpath        = args->nfs_server.export_path,
1727                 .protocol       = args->mount_server.protocol,
1728                 .fh             = root_fh,
1729                 .noresvport     = args->flags & NFS_MOUNT_NORESVPORT,
1730                 .auth_flav_len  = server_authlist_len,
1731                 .auth_flavs     = server_authlist,
1732                 .net            = args->net,
1733         };
1734         int status;
1735 
1736         if (args->mount_server.version == 0) {
1737                 switch (args->version) {
1738                         default:
1739                                 args->mount_server.version = NFS_MNT3_VERSION;
1740                                 break;
1741                         case 2:
1742                                 args->mount_server.version = NFS_MNT_VERSION;
1743                 }
1744         }
1745         request.version = args->mount_server.version;
1746 
1747         if (args->mount_server.hostname)
1748                 request.hostname = args->mount_server.hostname;
1749         else
1750                 request.hostname = args->nfs_server.hostname;
1751 
1752         /*
1753          * Construct the mount server's address.
1754          */
1755         if (args->mount_server.address.ss_family == AF_UNSPEC) {
1756                 memcpy(request.sap, &args->nfs_server.address,
1757                        args->nfs_server.addrlen);
1758                 args->mount_server.addrlen = args->nfs_server.addrlen;
1759         }
1760         request.salen = args->mount_server.addrlen;
1761         nfs_set_port(request.sap, &args->mount_server.port, 0);
1762 
1763         /*
1764          * Now ask the mount server to map our export path
1765          * to a file handle.
1766          */
1767         status = nfs_mount(&request);
1768         if (status != 0) {
1769                 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1770                                 request.hostname, status);
1771                 return status;
1772         }
1773 
1774         return 0;
1775 }
1776 
1777 static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1778                                         struct nfs_subversion *nfs_mod)
1779 {
1780         int status;
1781         unsigned int i;
1782         bool tried_auth_unix = false;
1783         bool auth_null_in_list = false;
1784         struct nfs_server *server = ERR_PTR(-EACCES);
1785         struct nfs_parsed_mount_data *args = mount_info->parsed;
1786         rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1787         unsigned int authlist_len = ARRAY_SIZE(authlist);
1788 
1789         status = nfs_request_mount(args, mount_info->mntfh, authlist,
1790                                         &authlist_len);
1791         if (status)
1792                 return ERR_PTR(status);
1793 
1794         /*
1795          * Was a sec= authflavor specified in the options? First, verify
1796          * whether the server supports it, and then just try to use it if so.
1797          */
1798         if (args->auth_info.flavor_len > 0) {
1799                 status = nfs_verify_authflavors(args, authlist, authlist_len);
1800                 dfprintk(MOUNT, "NFS: using auth flavor %u\n",
1801                          args->selected_flavor);
1802                 if (status)
1803                         return ERR_PTR(status);
1804                 return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1805         }
1806 
1807         /*
1808          * No sec= option was provided. RFC 2623, section 2.7 suggests we
1809          * SHOULD prefer the flavor listed first. However, some servers list
1810          * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1811          */
1812         for (i = 0; i < authlist_len; ++i) {
1813                 rpc_authflavor_t flavor;
1814                 struct rpcsec_gss_info info;
1815 
1816                 flavor = authlist[i];
1817                 switch (flavor) {
1818                 case RPC_AUTH_UNIX:
1819                         tried_auth_unix = true;
1820                         break;
1821                 case RPC_AUTH_NULL:
1822                         auth_null_in_list = true;
1823                         continue;
1824                 default:
1825                         if (rpcauth_get_gssinfo(flavor, &info) != 0)
1826                                 continue;
1827                         /* Fallthrough */
1828                 }
1829                 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1830                 args->selected_flavor = flavor;
1831                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1832                 if (!IS_ERR(server))
1833                         return server;
1834         }
1835 
1836         /*
1837          * Nothing we tried so far worked. At this point, give up if we've
1838          * already tried AUTH_UNIX or if the server's list doesn't contain
1839          * AUTH_NULL
1840          */
1841         if (tried_auth_unix || !auth_null_in_list)
1842                 return server;
1843 
1844         /* Last chance! Try AUTH_UNIX */
1845         dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1846         args->selected_flavor = RPC_AUTH_UNIX;
1847         return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1848 }
1849 
1850 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1851                              struct nfs_mount_info *mount_info,
1852                              struct nfs_subversion *nfs_mod)
1853 {
1854         struct nfs_server *server;
1855 
1856         if (mount_info->parsed->need_mount)
1857                 server = nfs_try_mount_request(mount_info, nfs_mod);
1858         else
1859                 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1860 
1861         if (IS_ERR(server))
1862                 return ERR_CAST(server);
1863 
1864         return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1865 }
1866 EXPORT_SYMBOL_GPL(nfs_try_mount);
1867 
1868 /*
1869  * Split "dev_name" into "hostname:export_path".
1870  *
1871  * The leftmost colon demarks the split between the server's hostname
1872  * and the export path.  If the hostname starts with a left square
1873  * bracket, then it may contain colons.
1874  *
1875  * Note: caller frees hostname and export path, even on error.
1876  */
1877 static int nfs_parse_devname(const char *dev_name,
1878                              char **hostname, size_t maxnamlen,
1879                              char **export_path, size_t maxpathlen)
1880 {
1881         size_t len;
1882         char *end;
1883 
1884         /* Is the host name protected with square brakcets? */
1885         if (*dev_name == '[') {
1886                 end = strchr(++dev_name, ']');
1887                 if (end == NULL || end[1] != ':')
1888                         goto out_bad_devname;
1889 
1890                 len = end - dev_name;
1891                 end++;
1892         } else {
1893                 char *comma;
1894 
1895                 end = strchr(dev_name, ':');
1896                 if (end == NULL)
1897                         goto out_bad_devname;
1898                 len = end - dev_name;
1899 
1900                 /* kill possible hostname list: not supported */
1901                 comma = strchr(dev_name, ',');
1902                 if (comma != NULL && comma < end)
1903                         *comma = 0;
1904         }
1905 
1906         if (len > maxnamlen)
1907                 goto out_hostname;
1908 
1909         /* N.B. caller will free nfs_server.hostname in all cases */
1910         *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1911         if (*hostname == NULL)
1912                 goto out_nomem;
1913         len = strlen(++end);
1914         if (len > maxpathlen)
1915                 goto out_path;
1916         *export_path = kstrndup(end, len, GFP_KERNEL);
1917         if (!*export_path)
1918                 goto out_nomem;
1919 
1920         dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1921         return 0;
1922 
1923 out_bad_devname:
1924         dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1925         return -EINVAL;
1926 
1927 out_nomem:
1928         dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1929         return -ENOMEM;
1930 
1931 out_hostname:
1932         dfprintk(MOUNT, "NFS: server hostname too long\n");
1933         return -ENAMETOOLONG;
1934 
1935 out_path:
1936         dfprintk(MOUNT, "NFS: export pathname too long\n");
1937         return -ENAMETOOLONG;
1938 }
1939 
1940 /*
1941  * Validate the NFS2/NFS3 mount data
1942  * - fills in the mount root filehandle
1943  *
1944  * For option strings, user space handles the following behaviors:
1945  *
1946  * + DNS: mapping server host name to IP address ("addr=" option)
1947  *
1948  * + failure mode: how to behave if a mount request can't be handled
1949  *   immediately ("fg/bg" option)
1950  *
1951  * + retry: how often to retry a mount request ("retry=" option)
1952  *
1953  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1954  *   mountproto=tcp after mountproto=udp, and so on
1955  */
1956 static int nfs23_validate_mount_data(void *options,
1957                                      struct nfs_parsed_mount_data *args,
1958                                      struct nfs_fh *mntfh,
1959                                      const char *dev_name)
1960 {
1961         struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1962         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1963         int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1964 
1965         if (data == NULL)
1966                 goto out_no_data;
1967 
1968         args->version = NFS_DEFAULT_VERSION;
1969         switch (data->version) {
1970         case 1:
1971                 data->namlen = 0;
1972         case 2:
1973                 data->bsize = 0;
1974         case 3:
1975                 if (data->flags & NFS_MOUNT_VER3)
1976                         goto out_no_v3;
1977                 data->root.size = NFS2_FHSIZE;
1978                 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1979                 /* Turn off security negotiation */
1980                 extra_flags |= NFS_MOUNT_SECFLAVOUR;
1981         case 4:
1982                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
1983                         goto out_no_sec;
1984         case 5:
1985                 memset(data->context, 0, sizeof(data->context));
1986         case 6:
1987                 if (data->flags & NFS_MOUNT_VER3) {
1988                         if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1989                                 goto out_invalid_fh;
1990                         mntfh->size = data->root.size;
1991                         args->version = 3;
1992                 } else {
1993                         mntfh->size = NFS2_FHSIZE;
1994                         args->version = 2;
1995                 }
1996 
1997 
1998                 memcpy(mntfh->data, data->root.data, mntfh->size);
1999                 if (mntfh->size < sizeof(mntfh->data))
2000                         memset(mntfh->data + mntfh->size, 0,
2001                                sizeof(mntfh->data) - mntfh->size);
2002 
2003                 /*
2004                  * Translate to nfs_parsed_mount_data, which nfs_fill_super
2005                  * can deal with.
2006                  */
2007                 args->flags             = data->flags & NFS_MOUNT_FLAGMASK;
2008                 args->flags             |= extra_flags;
2009                 args->rsize             = data->rsize;
2010                 args->wsize             = data->wsize;
2011                 args->timeo             = data->timeo;
2012                 args->retrans           = data->retrans;
2013                 args->acregmin          = data->acregmin;
2014                 args->acregmax          = data->acregmax;
2015                 args->acdirmin          = data->acdirmin;
2016                 args->acdirmax          = data->acdirmax;
2017                 args->need_mount        = false;
2018 
2019                 memcpy(sap, &data->addr, sizeof(data->addr));
2020                 args->nfs_server.addrlen = sizeof(data->addr);
2021                 args->nfs_server.port = ntohs(data->addr.sin_port);
2022                 if (!nfs_verify_server_address(sap))
2023                         goto out_no_address;
2024 
2025                 if (!(data->flags & NFS_MOUNT_TCP))
2026                         args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
2027                 /* N.B. caller will free nfs_server.hostname in all cases */
2028                 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
2029                 args->namlen            = data->namlen;
2030                 args->bsize             = data->bsize;
2031 
2032                 if (data->flags & NFS_MOUNT_SECFLAVOUR)
2033                         args->selected_flavor = data->pseudoflavor;
2034                 else
2035                         args->selected_flavor = RPC_AUTH_UNIX;
2036                 if (!args->nfs_server.hostname)
2037                         goto out_nomem;
2038 
2039                 if (!(data->flags & NFS_MOUNT_NONLM))
2040                         args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
2041                                          NFS_MOUNT_LOCAL_FCNTL);
2042                 else
2043                         args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
2044                                         NFS_MOUNT_LOCAL_FCNTL);
2045                 /*
2046                  * The legacy version 6 binary mount data from userspace has a
2047                  * field used only to transport selinux information into the
2048                  * the kernel.  To continue to support that functionality we
2049                  * have a touch of selinux knowledge here in the NFS code. The
2050                  * userspace code converted context=blah to just blah so we are
2051                  * converting back to the full string selinux understands.
2052                  */
2053                 if (data->context[0]){
2054 #ifdef CONFIG_SECURITY_SELINUX
2055                         int rc;
2056                         char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
2057                         if (!opts_str)
2058                                 return -ENOMEM;
2059                         strcpy(opts_str, "context=");
2060                         data->context[NFS_MAX_CONTEXT_LEN] = '\0';
2061                         strcat(opts_str, &data->context[0]);
2062                         rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
2063                         kfree(opts_str);
2064                         if (rc)
2065                                 return rc;
2066 #else
2067                         return -EINVAL;
2068 #endif
2069                 }
2070 
2071                 break;
2072         default:
2073                 return NFS_TEXT_DATA;
2074         }
2075 
2076         return 0;
2077 
2078 out_no_data:
2079         dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2080         return -EINVAL;
2081 
2082 out_no_v3:
2083         dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2084                  data->version);
2085         return -EINVAL;
2086 
2087 out_no_sec:
2088         dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2089         return -EINVAL;
2090 
2091 out_nomem:
2092         dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2093         return -ENOMEM;
2094 
2095 out_no_address:
2096         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2097         return -EINVAL;
2098 
2099 out_invalid_fh:
2100         dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2101         return -EINVAL;
2102 }
2103 
2104 #if IS_ENABLED(CONFIG_NFS_V4)
2105 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2106                                    void *options,
2107                                    struct nfs_parsed_mount_data *args,
2108                                    struct nfs_fh *mntfh,
2109                                    const char *dev_name)
2110 {
2111         if (fs_type == &nfs_fs_type)
2112                 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2113         return nfs4_validate_mount_data(options, args, dev_name);
2114 }
2115 #else
2116 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2117                                    void *options,
2118                                    struct nfs_parsed_mount_data *args,
2119                                    struct nfs_fh *mntfh,
2120                                    const char *dev_name)
2121 {
2122         return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2123 }
2124 #endif
2125 
2126 static int nfs_validate_text_mount_data(void *options,
2127                                         struct nfs_parsed_mount_data *args,
2128                                         const char *dev_name)
2129 {
2130         int port = 0;
2131         int max_namelen = PAGE_SIZE;
2132         int max_pathlen = NFS_MAXPATHLEN;
2133         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2134 
2135         if (nfs_parse_mount_options((char *)options, args) == 0)
2136                 return -EINVAL;
2137 
2138         if (!nfs_verify_server_address(sap))
2139                 goto out_no_address;
2140 
2141         if (args->version == 4) {
2142 #if IS_ENABLED(CONFIG_NFS_V4)
2143                 port = NFS_PORT;
2144                 max_namelen = NFS4_MAXNAMLEN;
2145                 max_pathlen = NFS4_MAXPATHLEN;
2146                 nfs_validate_transport_protocol(args);
2147                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2148                         goto out_invalid_transport_udp;
2149                 nfs4_validate_mount_flags(args);
2150 #else
2151                 goto out_v4_not_compiled;
2152 #endif /* CONFIG_NFS_V4 */
2153         } else
2154                 nfs_set_mount_transport_protocol(args);
2155 
2156         nfs_set_port(sap, &args->nfs_server.port, port);
2157 
2158         return nfs_parse_devname(dev_name,
2159                                    &args->nfs_server.hostname,
2160                                    max_namelen,
2161                                    &args->nfs_server.export_path,
2162                                    max_pathlen);
2163 
2164 #if !IS_ENABLED(CONFIG_NFS_V4)
2165 out_v4_not_compiled:
2166         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2167         return -EPROTONOSUPPORT;
2168 #else
2169 out_invalid_transport_udp:
2170         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2171         return -EINVAL;
2172 #endif /* !CONFIG_NFS_V4 */
2173 
2174 out_no_address:
2175         dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2176         return -EINVAL;
2177 }
2178 
2179 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
2180                 | NFS_MOUNT_SECURE \
2181                 | NFS_MOUNT_TCP \
2182                 | NFS_MOUNT_VER3 \
2183                 | NFS_MOUNT_KERBEROS \
2184                 | NFS_MOUNT_NONLM \
2185                 | NFS_MOUNT_BROKEN_SUID \
2186                 | NFS_MOUNT_STRICTLOCK \
2187                 | NFS_MOUNT_LEGACY_INTERFACE)
2188 
2189 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
2190                 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
2191 
2192 static int
2193 nfs_compare_remount_data(struct nfs_server *nfss,
2194                          struct nfs_parsed_mount_data *data)
2195 {
2196         if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
2197             data->rsize != nfss->rsize ||
2198             data->wsize != nfss->wsize ||
2199             data->version != nfss->nfs_client->rpc_ops->version ||
2200             data->minorversion != nfss->nfs_client->cl_minorversion ||
2201             data->retrans != nfss->client->cl_timeout->to_retries ||
2202             !nfs_auth_info_match(&data->auth_info, nfss->client->cl_auth->au_flavor) ||
2203             data->acregmin != nfss->acregmin / HZ ||
2204             data->acregmax != nfss->acregmax / HZ ||
2205             data->acdirmin != nfss->acdirmin / HZ ||
2206             data->acdirmax != nfss->acdirmax / HZ ||
2207             data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2208             data->nfs_server.port != nfss->port ||
2209             data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2210             !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2211                           (struct sockaddr *)&nfss->nfs_client->cl_addr))
2212                 return -EINVAL;
2213 
2214         return 0;
2215 }
2216 
2217 int
2218 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2219 {
2220         int error;
2221         struct nfs_server *nfss = sb->s_fs_info;
2222         struct nfs_parsed_mount_data *data;
2223         struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2224         struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2225         u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2226 
2227         sync_filesystem(sb);
2228 
2229         /*
2230          * Userspace mount programs that send binary options generally send
2231          * them populated with default values. We have no way to know which
2232          * ones were explicitly specified. Fall back to legacy behavior and
2233          * just return success.
2234          */
2235         if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2236             (nfsvers <= 3 && (!options || (options->version >= 1 &&
2237                                            options->version <= 6))))
2238                 return 0;
2239 
2240         data = kzalloc(sizeof(*data), GFP_KERNEL);
2241         if (data == NULL)
2242                 return -ENOMEM;
2243 
2244         /* fill out struct with values from existing mount */
2245         data->flags = nfss->flags;
2246         data->rsize = nfss->rsize;
2247         data->wsize = nfss->wsize;
2248         data->retrans = nfss->client->cl_timeout->to_retries;
2249         data->selected_flavor = nfss->client->cl_auth->au_flavor;
2250         data->acregmin = nfss->acregmin / HZ;
2251         data->acregmax = nfss->acregmax / HZ;
2252         data->acdirmin = nfss->acdirmin / HZ;
2253         data->acdirmax = nfss->acdirmax / HZ;
2254         data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2255         data->nfs_server.port = nfss->port;
2256         data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2257         data->version = nfsvers;
2258         data->minorversion = nfss->nfs_client->cl_minorversion;
2259         data->net = current->nsproxy->net_ns;
2260         memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2261                 data->nfs_server.addrlen);
2262 
2263         /* overwrite those values with any that were specified */
2264         error = -EINVAL;
2265         if (!nfs_parse_mount_options((char *)options, data))
2266                 goto out;
2267 
2268         /*
2269          * noac is a special case. It implies -o sync, but that's not
2270          * necessarily reflected in the mtab options. do_remount_sb
2271          * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2272          * remount options, so we have to explicitly reset it.
2273          */
2274         if (data->flags & NFS_MOUNT_NOAC)
2275                 *flags |= MS_SYNCHRONOUS;
2276 
2277         /* compare new mount options with old ones */
2278         error = nfs_compare_remount_data(nfss, data);
2279 out:
2280         kfree(data);
2281         return error;
2282 }
2283 EXPORT_SYMBOL_GPL(nfs_remount);
2284 
2285 /*
2286  * Initialise the common bits of the superblock
2287  */
2288 inline void nfs_initialise_sb(struct super_block *sb)
2289 {
2290         struct nfs_server *server = NFS_SB(sb);
2291 
2292         sb->s_magic = NFS_SUPER_MAGIC;
2293 
2294         /* We probably want something more informative here */
2295         snprintf(sb->s_id, sizeof(sb->s_id),
2296                  "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2297 
2298         if (sb->s_blocksize == 0)
2299                 sb->s_blocksize = nfs_block_bits(server->wsize,
2300                                                  &sb->s_blocksize_bits);
2301 
2302         sb->s_bdi = &server->backing_dev_info;
2303 
2304         nfs_super_set_maxbytes(sb, server->maxfilesize);
2305 }
2306 
2307 /*
2308  * Finish setting up an NFS2/3 superblock
2309  */
2310 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2311 {
2312         struct nfs_parsed_mount_data *data = mount_info->parsed;
2313         struct nfs_server *server = NFS_SB(sb);
2314 
2315         sb->s_blocksize_bits = 0;
2316         sb->s_blocksize = 0;
2317         sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2318         sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2319         if (data && data->bsize)
2320                 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2321 
2322         if (server->nfs_client->rpc_ops->version != 2) {
2323                 /* The VFS shouldn't apply the umask to mode bits. We will do
2324                  * so ourselves when necessary.
2325                  */
2326                 sb->s_flags |= MS_POSIXACL;
2327                 sb->s_time_gran = 1;
2328         }
2329 
2330         nfs_initialise_sb(sb);
2331 }
2332 EXPORT_SYMBOL_GPL(nfs_fill_super);
2333 
2334 /*
2335  * Finish setting up a cloned NFS2/3/4 superblock
2336  */
2337 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2338 {
2339         const struct super_block *old_sb = mount_info->cloned->sb;
2340         struct nfs_server *server = NFS_SB(sb);
2341 
2342         sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2343         sb->s_blocksize = old_sb->s_blocksize;
2344         sb->s_maxbytes = old_sb->s_maxbytes;
2345         sb->s_xattr = old_sb->s_xattr;
2346         sb->s_op = old_sb->s_op;
2347         sb->s_time_gran = 1;
2348 
2349         if (server->nfs_client->rpc_ops->version != 2) {
2350                 /* The VFS shouldn't apply the umask to mode bits. We will do
2351                  * so ourselves when necessary.
2352                  */
2353                 sb->s_flags |= MS_POSIXACL;
2354         }
2355 
2356         nfs_initialise_sb(sb);
2357 }
2358 
2359 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2360 {
2361         const struct nfs_server *a = s->s_fs_info;
2362         const struct rpc_clnt *clnt_a = a->client;
2363         const struct rpc_clnt *clnt_b = b->client;
2364 
2365         if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2366                 goto Ebusy;
2367         if (a->nfs_client != b->nfs_client)
2368                 goto Ebusy;
2369         if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
2370                 goto Ebusy;
2371         if (a->wsize != b->wsize)
2372                 goto Ebusy;
2373         if (a->rsize != b->rsize)
2374                 goto Ebusy;
2375         if (a->acregmin != b->acregmin)
2376                 goto Ebusy;
2377         if (a->acregmax != b->acregmax)
2378                 goto Ebusy;
2379         if (a->acdirmin != b->acdirmin)
2380                 goto Ebusy;
2381         if (a->acdirmax != b->acdirmax)
2382                 goto Ebusy;
2383         if (b->auth_info.flavor_len > 0 &&
2384            clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2385                 goto Ebusy;
2386         return 1;
2387 Ebusy:
2388         return 0;
2389 }
2390 
2391 struct nfs_sb_mountdata {
2392         struct nfs_server *server;
2393         int mntflags;
2394 };
2395 
2396 static int nfs_set_super(struct super_block *s, void *data)
2397 {
2398         struct nfs_sb_mountdata *sb_mntdata = data;
2399         struct nfs_server *server = sb_mntdata->server;
2400         int ret;
2401 
2402         s->s_flags = sb_mntdata->mntflags;
2403         s->s_fs_info = server;
2404         s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2405         ret = set_anon_super(s, server);
2406         if (ret == 0)
2407                 server->s_dev = s->s_dev;
2408         return ret;
2409 }
2410 
2411 static int nfs_compare_super_address(struct nfs_server *server1,
2412                                      struct nfs_server *server2)
2413 {
2414         struct sockaddr *sap1, *sap2;
2415         struct rpc_xprt *xprt1 = server1->client->cl_xprt;
2416         struct rpc_xprt *xprt2 = server2->client->cl_xprt;
2417 
2418         if (!net_eq(xprt1->xprt_net, xprt2->xprt_net))
2419                 return 0;
2420 
2421         sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2422         sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2423 
2424         if (sap1->sa_family != sap2->sa_family)
2425                 return 0;
2426 
2427         switch (sap1->sa_family) {
2428         case AF_INET: {
2429                 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2430                 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2431                 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2432                         return 0;
2433                 if (sin1->sin_port != sin2->sin_port)
2434                         return 0;
2435                 break;
2436         }
2437         case AF_INET6: {
2438                 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2439                 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2440                 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2441                         return 0;
2442                 if (sin1->sin6_port != sin2->sin6_port)
2443                         return 0;
2444                 break;
2445         }
2446         default:
2447                 return 0;
2448         }
2449 
2450         return 1;
2451 }
2452 
2453 static int nfs_compare_super(struct super_block *sb, void *data)
2454 {
2455         struct nfs_sb_mountdata *sb_mntdata = data;
2456         struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2457         int mntflags = sb_mntdata->mntflags;
2458 
2459         if (!nfs_compare_super_address(old, server))
2460                 return 0;
2461         /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2462         if (old->flags & NFS_MOUNT_UNSHARED)
2463                 return 0;
2464         if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2465                 return 0;
2466         return nfs_compare_mount_options(sb, server, mntflags);
2467 }
2468 
2469 #ifdef CONFIG_NFS_FSCACHE
2470 static void nfs_get_cache_cookie(struct super_block *sb,
2471                                  struct nfs_parsed_mount_data *parsed,
2472                                  struct nfs_clone_mount *cloned)
2473 {
2474         struct nfs_server *nfss = NFS_SB(sb);
2475         char *uniq = NULL;
2476         int ulen = 0;
2477 
2478         nfss->fscache_key = NULL;
2479         nfss->fscache = NULL;
2480 
2481         if (parsed) {
2482                 if (!(parsed->options & NFS_OPTION_FSCACHE))
2483                         return;
2484                 if (parsed->fscache_uniq) {
2485                         uniq = parsed->fscache_uniq;
2486                         ulen = strlen(parsed->fscache_uniq);
2487                 }
2488         } else if (cloned) {
2489                 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2490                 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2491                         return;
2492                 if (mnt_s->fscache_key) {
2493                         uniq = mnt_s->fscache_key->key.uniquifier;
2494                         ulen = mnt_s->fscache_key->key.uniq_len;
2495                 };
2496         } else
2497                 return;
2498 
2499         nfs_fscache_get_super_cookie(sb, uniq, ulen);
2500 }
2501 #else
2502 static void nfs_get_cache_cookie(struct super_block *sb,
2503                                  struct nfs_parsed_mount_data *parsed,
2504                                  struct nfs_clone_mount *cloned)
2505 {
2506 }
2507 #endif
2508 
2509 static int nfs_bdi_register(struct nfs_server *server)
2510 {
2511         return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2512 }
2513 
2514 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2515                         struct nfs_mount_info *mount_info)
2516 {
2517         int error;
2518         unsigned long kflags = 0, kflags_out = 0;
2519         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2520                 kflags |= SECURITY_LSM_NATIVE_LABELS;
2521 
2522         error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
2523                                                 kflags, &kflags_out);
2524         if (error)
2525                 goto err;
2526 
2527         if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2528                 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2529                 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2530 err:
2531         return error;
2532 }
2533 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2534 
2535 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2536                           struct nfs_mount_info *mount_info)
2537 {
2538         /* clone any lsm security options from the parent to the new sb */
2539         if (d_inode(mntroot)->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2540                 return -ESTALE;
2541         return security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2542 }
2543 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2544 
2545 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2546                                    int flags, const char *dev_name,
2547                                    struct nfs_mount_info *mount_info,
2548                                    struct nfs_subversion *nfs_mod)
2549 {
2550         struct super_block *s;
2551         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2552         int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2553         struct nfs_sb_mountdata sb_mntdata = {
2554                 .mntflags = flags,
2555                 .server = server,
2556         };
2557         int error;
2558 
2559         if (server->flags & NFS_MOUNT_UNSHARED)
2560                 compare_super = NULL;
2561 
2562         /* -o noac implies -o sync */
2563         if (server->flags & NFS_MOUNT_NOAC)
2564                 sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2565 
2566         if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
2567                 if (mount_info->cloned->sb->s_flags & MS_SYNCHRONOUS)
2568                         sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2569 
2570         /* Get a superblock - note that we may end up sharing one that already exists */
2571         s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2572         if (IS_ERR(s)) {
2573                 mntroot = ERR_CAST(s);
2574                 goto out_err_nosb;
2575         }
2576 
2577         if (s->s_fs_info != server) {
2578                 nfs_free_server(server);
2579                 server = NULL;
2580         } else {
2581                 error = nfs_bdi_register(server);
2582                 if (error) {
2583                         mntroot = ERR_PTR(error);
2584                         goto error_splat_super;
2585                 }
2586                 server->super = s;
2587         }
2588 
2589         if (!s->s_root) {
2590                 /* initial superblock/root creation */
2591                 mount_info->fill_super(s, mount_info);
2592                 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2593         }
2594 
2595         mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2596         if (IS_ERR(mntroot))
2597                 goto error_splat_super;
2598 
2599         error = mount_info->set_security(s, mntroot, mount_info);
2600         if (error)
2601                 goto error_splat_root;
2602 
2603         s->s_flags |= MS_ACTIVE;
2604 
2605 out:
2606         return mntroot;
2607 
2608 out_err_nosb:
2609         nfs_free_server(server);
2610         goto out;
2611 
2612 error_splat_root:
2613         dput(mntroot);
2614         mntroot = ERR_PTR(error);
2615 error_splat_super:
2616         deactivate_locked_super(s);
2617         goto out;
2618 }
2619 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2620 
2621 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2622         int flags, const char *dev_name, void *raw_data)
2623 {
2624         struct nfs_mount_info mount_info = {
2625                 .fill_super = nfs_fill_super,
2626                 .set_security = nfs_set_sb_security,
2627         };
2628         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2629         struct nfs_subversion *nfs_mod;
2630         int error;
2631 
2632         mount_info.parsed = nfs_alloc_parsed_mount_data();
2633         mount_info.mntfh = nfs_alloc_fhandle();
2634         if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2635                 goto out;
2636 
2637         /* Validate the mount data */
2638         error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2639         if (error == NFS_TEXT_DATA)
2640                 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2641         if (error < 0) {
2642                 mntroot = ERR_PTR(error);
2643                 goto out;
2644         }
2645 
2646         nfs_mod = get_nfs_version(mount_info.parsed->version);
2647         if (IS_ERR(nfs_mod)) {
2648                 mntroot = ERR_CAST(nfs_mod);
2649                 goto out;
2650         }
2651 
2652         mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2653 
2654         put_nfs_version(nfs_mod);
2655 out:
2656         nfs_free_parsed_mount_data(mount_info.parsed);
2657         nfs_free_fhandle(mount_info.mntfh);
2658         return mntroot;
2659 }
2660 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2661 
2662 /*
2663  * Destroy an NFS2/3 superblock
2664  */
2665 void nfs_kill_super(struct super_block *s)
2666 {
2667         struct nfs_server *server = NFS_SB(s);
2668         dev_t dev = s->s_dev;
2669 
2670         generic_shutdown_super(s);
2671 
2672         nfs_fscache_release_super_cookie(s);
2673 
2674         nfs_free_server(server);
2675         free_anon_bdev(dev);
2676 }
2677 EXPORT_SYMBOL_GPL(nfs_kill_super);
2678 
2679 /*
2680  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2681  */
2682 static struct dentry *
2683 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2684                 const char *dev_name, void *raw_data)
2685 {
2686         struct nfs_clone_mount *data = raw_data;
2687         struct nfs_mount_info mount_info = {
2688                 .fill_super = nfs_clone_super,
2689                 .set_security = nfs_clone_sb_security,
2690                 .cloned = data,
2691         };
2692         struct nfs_server *server;
2693         struct dentry *mntroot = ERR_PTR(-ENOMEM);
2694         struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2695 
2696         dprintk("--> nfs_xdev_mount()\n");
2697 
2698         mount_info.mntfh = mount_info.cloned->fh;
2699 
2700         /* create a new volume representation */
2701         server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2702 
2703         if (IS_ERR(server))
2704                 mntroot = ERR_CAST(server);
2705         else
2706                 mntroot = nfs_fs_mount_common(server, flags,
2707                                 dev_name, &mount_info, nfs_mod);
2708 
2709         dprintk("<-- nfs_xdev_mount() = %ld\n",
2710                         IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2711         return mntroot;
2712 }
2713 
2714 #if IS_ENABLED(CONFIG_NFS_V4)
2715 
2716 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2717 {
2718         args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2719                          NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2720 }
2721 
2722 /*
2723  * Validate NFSv4 mount options
2724  */
2725 static int nfs4_validate_mount_data(void *options,
2726                                     struct nfs_parsed_mount_data *args,
2727                                     const char *dev_name)
2728 {
2729         struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2730         struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2731         char *c;
2732 
2733         if (data == NULL)
2734                 goto out_no_data;
2735 
2736         args->version = 4;
2737 
2738         switch (data->version) {
2739         case 1:
2740                 if (data->host_addrlen > sizeof(args->nfs_server.address))
2741                         goto out_no_address;
2742                 if (data->host_addrlen == 0)
2743                         goto out_no_address;
2744                 args->nfs_server.addrlen = data->host_addrlen;
2745                 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2746                         return -EFAULT;
2747                 if (!nfs_verify_server_address(sap))
2748                         goto out_no_address;
2749                 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2750 
2751                 if (data->auth_flavourlen) {
2752                         rpc_authflavor_t pseudoflavor;
2753                         if (data->auth_flavourlen > 1)
2754                                 goto out_inval_auth;
2755                         if (copy_from_user(&pseudoflavor,
2756                                            data->auth_flavours,
2757                                            sizeof(pseudoflavor)))
2758                                 return -EFAULT;
2759                         args->selected_flavor = pseudoflavor;
2760                 } else
2761                         args->selected_flavor = RPC_AUTH_UNIX;
2762 
2763                 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2764                 if (IS_ERR(c))
2765                         return PTR_ERR(c);
2766                 args->nfs_server.hostname = c;
2767 
2768                 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2769                 if (IS_ERR(c))
2770                         return PTR_ERR(c);
2771                 args->nfs_server.export_path = c;
2772                 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2773 
2774                 c = strndup_user(data->client_addr.data, 16);
2775                 if (IS_ERR(c))
2776                         return PTR_ERR(c);
2777                 args->client_address = c;
2778 
2779                 /*
2780                  * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2781                  * can deal with.
2782                  */
2783 
2784                 args->flags     = data->flags & NFS4_MOUNT_FLAGMASK;
2785                 args->rsize     = data->rsize;
2786                 args->wsize     = data->wsize;
2787                 args->timeo     = data->timeo;
2788                 args->retrans   = data->retrans;
2789                 args->acregmin  = data->acregmin;
2790                 args->acregmax  = data->acregmax;
2791                 args->acdirmin  = data->acdirmin;
2792                 args->acdirmax  = data->acdirmax;
2793                 args->nfs_server.protocol = data->proto;
2794                 nfs_validate_transport_protocol(args);
2795                 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2796                         goto out_invalid_transport_udp;
2797 
2798                 break;
2799         default:
2800                 return NFS_TEXT_DATA;
2801         }
2802 
2803         return 0;
2804 
2805 out_no_data:
2806         dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2807         return -EINVAL;
2808 
2809 out_inval_auth:
2810         dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2811                  data->auth_flavourlen);
2812         return -EINVAL;
2813 
2814 out_no_address:
2815         dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2816         return -EINVAL;
2817 
2818 out_invalid_transport_udp:
2819         dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2820         return -EINVAL;
2821 }
2822 
2823 /*
2824  * NFS v4 module parameters need to stay in the
2825  * NFS client for backwards compatibility
2826  */
2827 unsigned int nfs_callback_set_tcpport;
2828 /* Default cache timeout is 10 minutes */
2829 unsigned int nfs_idmap_cache_timeout = 600;
2830 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2831 bool nfs4_disable_idmapping = true;
2832 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2833 unsigned short send_implementation_id = 1;
2834 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2835 bool recover_lost_locks = false;
2836 
2837 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2838 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2839 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2840 EXPORT_SYMBOL_GPL(max_session_slots);
2841 EXPORT_SYMBOL_GPL(send_implementation_id);
2842 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2843 EXPORT_SYMBOL_GPL(recover_lost_locks);
2844 
2845 #define NFS_CALLBACK_MAXPORTNR (65535U)
2846 
2847 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2848 {
2849         unsigned long num;
2850         int ret;
2851 
2852         if (!val)
2853                 return -EINVAL;
2854         ret = kstrtoul(val, 0, &num);
2855         if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2856                 return -EINVAL;
2857         *((unsigned int *)kp->arg) = num;
2858         return 0;
2859 }
2860 static const struct kernel_param_ops param_ops_portnr = {
2861         .set = param_set_portnr,
2862         .get = param_get_uint,
2863 };
2864 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2865 
2866 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2867 module_param(nfs_idmap_cache_timeout, int, 0644);
2868 module_param(nfs4_disable_idmapping, bool, 0644);
2869 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2870                         NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2871 MODULE_PARM_DESC(nfs4_disable_idmapping,
2872                 "Turn off NFSv4 idmapping when using 'sec=sys'");
2873 module_param(max_session_slots, ushort, 0644);
2874 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2875                 "requests the client will negotiate");
2876 module_param(send_implementation_id, ushort, 0644);
2877 MODULE_PARM_DESC(send_implementation_id,
2878                 "Send implementation ID with NFSv4.1 exchange_id");
2879 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2880 
2881 module_param(recover_lost_locks, bool, 0644);
2882 MODULE_PARM_DESC(recover_lost_locks,
2883                  "If the server reports that a lock might be lost, "
2884                  "try to recover it risking data corruption.");
2885 
2886 
2887 #endif /* CONFIG_NFS_V4 */
2888 

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