1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * linux/fs/nfs/super.c
4 *
5 * Copyright (C) 1992 Rick Sladkey
6 *
7 * nfs superblock handling functions
8 *
9 * Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
10 * experimental NFS changes. Modularisation taken straight from SYS5 fs.
11 *
12 * Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
13 * J.S.Peatfield@damtp.cam.ac.uk
14 *
15 * Split from inode.c by David Howells <dhowells@redhat.com>
16 *
17 * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
18 * particular server are held in the same superblock
19 * - NFS superblocks can have several effective roots to the dentry tree
20 * - directory type roots are spliced into the tree when a path from one root reaches the root
21 * of another (see nfs_lookup())
22 */
23
24 #include <linux/module.h>
25 #include <linux/init.h>
26
27 #include <linux/time.h>
28 #include <linux/kernel.h>
29 #include <linux/mm.h>
30 #include <linux/string.h>
31 #include <linux/stat.h>
32 #include <linux/errno.h>
33 #include <linux/unistd.h>
34 #include <linux/sunrpc/clnt.h>
35 #include <linux/sunrpc/addr.h>
36 #include <linux/sunrpc/stats.h>
37 #include <linux/sunrpc/metrics.h>
38 #include <linux/sunrpc/xprtsock.h>
39 #include <linux/sunrpc/xprtrdma.h>
40 #include <linux/nfs_fs.h>
41 #include <linux/nfs_mount.h>
42 #include <linux/nfs4_mount.h>
43 #include <linux/lockd/bind.h>
44 #include <linux/seq_file.h>
45 #include <linux/mount.h>
46 #include <linux/namei.h>
47 #include <linux/vfs.h>
48 #include <linux/inet.h>
49 #include <linux/in6.h>
50 #include <linux/slab.h>
51 #include <net/ipv6.h>
52 #include <linux/netdevice.h>
53 #include <linux/nfs_xdr.h>
54 #include <linux/magic.h>
55 #include <linux/parser.h>
56 #include <linux/nsproxy.h>
57 #include <linux/rcupdate.h>
58
59 #include <linux/uaccess.h>
60
61 #include "nfs4_fs.h"
62 #include "callback.h"
63 #include "delegation.h"
64 #include "iostat.h"
65 #include "internal.h"
66 #include "fscache.h"
67 #include "nfs4session.h"
68 #include "pnfs.h"
69 #include "nfs.h"
70
71 #define NFSDBG_FACILITY NFSDBG_VFS
72 #define NFS_TEXT_DATA 1
73
74 #if IS_ENABLED(CONFIG_NFS_V3)
75 #define NFS_DEFAULT_VERSION 3
76 #else
77 #define NFS_DEFAULT_VERSION 2
78 #endif
79
80 #define NFS_MAX_CONNECTIONS 16
81
82 enum {
83 /* Mount options that take no arguments */
84 Opt_soft, Opt_softerr, Opt_hard,
85 Opt_posix, Opt_noposix,
86 Opt_cto, Opt_nocto,
87 Opt_ac, Opt_noac,
88 Opt_lock, Opt_nolock,
89 Opt_udp, Opt_tcp, Opt_rdma,
90 Opt_acl, Opt_noacl,
91 Opt_rdirplus, Opt_nordirplus,
92 Opt_sharecache, Opt_nosharecache,
93 Opt_resvport, Opt_noresvport,
94 Opt_fscache, Opt_nofscache,
95 Opt_migration, Opt_nomigration,
96
97 /* Mount options that take integer arguments */
98 Opt_port,
99 Opt_rsize, Opt_wsize, Opt_bsize,
100 Opt_timeo, Opt_retrans,
101 Opt_acregmin, Opt_acregmax,
102 Opt_acdirmin, Opt_acdirmax,
103 Opt_actimeo,
104 Opt_namelen,
105 Opt_mountport,
106 Opt_mountvers,
107 Opt_minorversion,
108
109 /* Mount options that take string arguments */
110 Opt_nfsvers,
111 Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
112 Opt_addr, Opt_mountaddr, Opt_clientaddr,
113 Opt_nconnect,
114 Opt_lookupcache,
115 Opt_fscache_uniq,
116 Opt_local_lock,
117
118 /* Special mount options */
119 Opt_userspace, Opt_deprecated, Opt_sloppy,
120
121 Opt_err
122 };
123
124 static const match_table_t nfs_mount_option_tokens = {
125 { Opt_userspace, "bg" },
126 { Opt_userspace, "fg" },
127 { Opt_userspace, "retry=%s" },
128
129 { Opt_sloppy, "sloppy" },
130
131 { Opt_soft, "soft" },
132 { Opt_softerr, "softerr" },
133 { Opt_hard, "hard" },
134 { Opt_deprecated, "intr" },
135 { Opt_deprecated, "nointr" },
136 { Opt_posix, "posix" },
137 { Opt_noposix, "noposix" },
138 { Opt_cto, "cto" },
139 { Opt_nocto, "nocto" },
140 { Opt_ac, "ac" },
141 { Opt_noac, "noac" },
142 { Opt_lock, "lock" },
143 { Opt_nolock, "nolock" },
144 { Opt_udp, "udp" },
145 { Opt_tcp, "tcp" },
146 { Opt_rdma, "rdma" },
147 { Opt_acl, "acl" },
148 { Opt_noacl, "noacl" },
149 { Opt_rdirplus, "rdirplus" },
150 { Opt_nordirplus, "nordirplus" },
151 { Opt_sharecache, "sharecache" },
152 { Opt_nosharecache, "nosharecache" },
153 { Opt_resvport, "resvport" },
154 { Opt_noresvport, "noresvport" },
155 { Opt_fscache, "fsc" },
156 { Opt_nofscache, "nofsc" },
157 { Opt_migration, "migration" },
158 { Opt_nomigration, "nomigration" },
159
160 { Opt_port, "port=%s" },
161 { Opt_rsize, "rsize=%s" },
162 { Opt_wsize, "wsize=%s" },
163 { Opt_bsize, "bsize=%s" },
164 { Opt_timeo, "timeo=%s" },
165 { Opt_retrans, "retrans=%s" },
166 { Opt_acregmin, "acregmin=%s" },
167 { Opt_acregmax, "acregmax=%s" },
168 { Opt_acdirmin, "acdirmin=%s" },
169 { Opt_acdirmax, "acdirmax=%s" },
170 { Opt_actimeo, "actimeo=%s" },
171 { Opt_namelen, "namlen=%s" },
172 { Opt_mountport, "mountport=%s" },
173 { Opt_mountvers, "mountvers=%s" },
174 { Opt_minorversion, "minorversion=%s" },
175
176 { Opt_nfsvers, "nfsvers=%s" },
177 { Opt_nfsvers, "vers=%s" },
178
179 { Opt_sec, "sec=%s" },
180 { Opt_proto, "proto=%s" },
181 { Opt_mountproto, "mountproto=%s" },
182 { Opt_addr, "addr=%s" },
183 { Opt_clientaddr, "clientaddr=%s" },
184 { Opt_mounthost, "mounthost=%s" },
185 { Opt_mountaddr, "mountaddr=%s" },
186
187 { Opt_nconnect, "nconnect=%s" },
188
189 { Opt_lookupcache, "lookupcache=%s" },
190 { Opt_fscache_uniq, "fsc=%s" },
191 { Opt_local_lock, "local_lock=%s" },
192
193 /* The following needs to be listed after all other options */
194 { Opt_nfsvers, "v%s" },
195
196 { Opt_err, NULL }
197 };
198
199 enum {
200 Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
201 Opt_xprt_rdma6,
202
203 Opt_xprt_err
204 };
205
206 static const match_table_t nfs_xprt_protocol_tokens = {
207 { Opt_xprt_udp, "udp" },
208 { Opt_xprt_udp6, "udp6" },
209 { Opt_xprt_tcp, "tcp" },
210 { Opt_xprt_tcp6, "tcp6" },
211 { Opt_xprt_rdma, "rdma" },
212 { Opt_xprt_rdma6, "rdma6" },
213
214 { Opt_xprt_err, NULL }
215 };
216
217 enum {
218 Opt_sec_none, Opt_sec_sys,
219 Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
220 Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
221 Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
222
223 Opt_sec_err
224 };
225
226 static const match_table_t nfs_secflavor_tokens = {
227 { Opt_sec_none, "none" },
228 { Opt_sec_none, "null" },
229 { Opt_sec_sys, "sys" },
230
231 { Opt_sec_krb5, "krb5" },
232 { Opt_sec_krb5i, "krb5i" },
233 { Opt_sec_krb5p, "krb5p" },
234
235 { Opt_sec_lkey, "lkey" },
236 { Opt_sec_lkeyi, "lkeyi" },
237 { Opt_sec_lkeyp, "lkeyp" },
238
239 { Opt_sec_spkm, "spkm3" },
240 { Opt_sec_spkmi, "spkm3i" },
241 { Opt_sec_spkmp, "spkm3p" },
242
243 { Opt_sec_err, NULL }
244 };
245
246 enum {
247 Opt_lookupcache_all, Opt_lookupcache_positive,
248 Opt_lookupcache_none,
249
250 Opt_lookupcache_err
251 };
252
253 static match_table_t nfs_lookupcache_tokens = {
254 { Opt_lookupcache_all, "all" },
255 { Opt_lookupcache_positive, "pos" },
256 { Opt_lookupcache_positive, "positive" },
257 { Opt_lookupcache_none, "none" },
258
259 { Opt_lookupcache_err, NULL }
260 };
261
262 enum {
263 Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
264 Opt_local_lock_none,
265
266 Opt_local_lock_err
267 };
268
269 static match_table_t nfs_local_lock_tokens = {
270 { Opt_local_lock_all, "all" },
271 { Opt_local_lock_flock, "flock" },
272 { Opt_local_lock_posix, "posix" },
273 { Opt_local_lock_none, "none" },
274
275 { Opt_local_lock_err, NULL }
276 };
277
278 enum {
279 Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
280 Opt_vers_4_1, Opt_vers_4_2,
281
282 Opt_vers_err
283 };
284
285 static match_table_t nfs_vers_tokens = {
286 { Opt_vers_2, "2" },
287 { Opt_vers_3, "3" },
288 { Opt_vers_4, "4" },
289 { Opt_vers_4_0, "4.0" },
290 { Opt_vers_4_1, "4.1" },
291 { Opt_vers_4_2, "4.2" },
292
293 { Opt_vers_err, NULL }
294 };
295
296 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
297 int flags, const char *dev_name, void *raw_data);
298
299 struct file_system_type nfs_fs_type = {
300 .owner = THIS_MODULE,
301 .name = "nfs",
302 .mount = nfs_fs_mount,
303 .kill_sb = nfs_kill_super,
304 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
305 };
306 MODULE_ALIAS_FS("nfs");
307 EXPORT_SYMBOL_GPL(nfs_fs_type);
308
309 struct file_system_type nfs_xdev_fs_type = {
310 .owner = THIS_MODULE,
311 .name = "nfs",
312 .mount = nfs_xdev_mount,
313 .kill_sb = nfs_kill_super,
314 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
315 };
316
317 const struct super_operations nfs_sops = {
318 .alloc_inode = nfs_alloc_inode,
319 .free_inode = nfs_free_inode,
320 .write_inode = nfs_write_inode,
321 .drop_inode = nfs_drop_inode,
322 .statfs = nfs_statfs,
323 .evict_inode = nfs_evict_inode,
324 .umount_begin = nfs_umount_begin,
325 .show_options = nfs_show_options,
326 .show_devname = nfs_show_devname,
327 .show_path = nfs_show_path,
328 .show_stats = nfs_show_stats,
329 .remount_fs = nfs_remount,
330 };
331 EXPORT_SYMBOL_GPL(nfs_sops);
332
333 #if IS_ENABLED(CONFIG_NFS_V4)
334 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
335 static int nfs4_validate_mount_data(void *options,
336 struct nfs_parsed_mount_data *args, const char *dev_name);
337
338 struct file_system_type nfs4_fs_type = {
339 .owner = THIS_MODULE,
340 .name = "nfs4",
341 .mount = nfs_fs_mount,
342 .kill_sb = nfs_kill_super,
343 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
344 };
345 MODULE_ALIAS_FS("nfs4");
346 MODULE_ALIAS("nfs4");
347 EXPORT_SYMBOL_GPL(nfs4_fs_type);
348
register_nfs4_fs(void)349 static int __init register_nfs4_fs(void)
350 {
351 return register_filesystem(&nfs4_fs_type);
352 }
353
unregister_nfs4_fs(void)354 static void unregister_nfs4_fs(void)
355 {
356 unregister_filesystem(&nfs4_fs_type);
357 }
358 #else
register_nfs4_fs(void)359 static int __init register_nfs4_fs(void)
360 {
361 return 0;
362 }
363
unregister_nfs4_fs(void)364 static void unregister_nfs4_fs(void)
365 {
366 }
367 #endif
368
369 static struct shrinker acl_shrinker = {
370 .count_objects = nfs_access_cache_count,
371 .scan_objects = nfs_access_cache_scan,
372 .seeks = DEFAULT_SEEKS,
373 };
374
375 /*
376 * Register the NFS filesystems
377 */
register_nfs_fs(void)378 int __init register_nfs_fs(void)
379 {
380 int ret;
381
382 ret = register_filesystem(&nfs_fs_type);
383 if (ret < 0)
384 goto error_0;
385
386 ret = register_nfs4_fs();
387 if (ret < 0)
388 goto error_1;
389
390 ret = nfs_register_sysctl();
391 if (ret < 0)
392 goto error_2;
393 ret = register_shrinker(&acl_shrinker);
394 if (ret < 0)
395 goto error_3;
396 return 0;
397 error_3:
398 nfs_unregister_sysctl();
399 error_2:
400 unregister_nfs4_fs();
401 error_1:
402 unregister_filesystem(&nfs_fs_type);
403 error_0:
404 return ret;
405 }
406
407 /*
408 * Unregister the NFS filesystems
409 */
unregister_nfs_fs(void)410 void __exit unregister_nfs_fs(void)
411 {
412 unregister_shrinker(&acl_shrinker);
413 nfs_unregister_sysctl();
414 unregister_nfs4_fs();
415 unregister_filesystem(&nfs_fs_type);
416 }
417
nfs_sb_active(struct super_block * sb)418 bool nfs_sb_active(struct super_block *sb)
419 {
420 struct nfs_server *server = NFS_SB(sb);
421
422 if (!atomic_inc_not_zero(&sb->s_active))
423 return false;
424 if (atomic_inc_return(&server->active) != 1)
425 atomic_dec(&sb->s_active);
426 return true;
427 }
428 EXPORT_SYMBOL_GPL(nfs_sb_active);
429
nfs_sb_deactive(struct super_block * sb)430 void nfs_sb_deactive(struct super_block *sb)
431 {
432 struct nfs_server *server = NFS_SB(sb);
433
434 if (atomic_dec_and_test(&server->active))
435 deactivate_super(sb);
436 }
437 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
438
439 /*
440 * Deliver file system statistics to userspace
441 */
nfs_statfs(struct dentry * dentry,struct kstatfs * buf)442 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
443 {
444 struct nfs_server *server = NFS_SB(dentry->d_sb);
445 unsigned char blockbits;
446 unsigned long blockres;
447 struct nfs_fh *fh = NFS_FH(d_inode(dentry));
448 struct nfs_fsstat res;
449 int error = -ENOMEM;
450
451 res.fattr = nfs_alloc_fattr();
452 if (res.fattr == NULL)
453 goto out_err;
454
455 error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
456 if (unlikely(error == -ESTALE)) {
457 struct dentry *pd_dentry;
458
459 pd_dentry = dget_parent(dentry);
460 nfs_zap_caches(d_inode(pd_dentry));
461 dput(pd_dentry);
462 }
463 nfs_free_fattr(res.fattr);
464 if (error < 0)
465 goto out_err;
466
467 buf->f_type = NFS_SUPER_MAGIC;
468
469 /*
470 * Current versions of glibc do not correctly handle the
471 * case where f_frsize != f_bsize. Eventually we want to
472 * report the value of wtmult in this field.
473 */
474 buf->f_frsize = dentry->d_sb->s_blocksize;
475
476 /*
477 * On most *nix systems, f_blocks, f_bfree, and f_bavail
478 * are reported in units of f_frsize. Linux hasn't had
479 * an f_frsize field in its statfs struct until recently,
480 * thus historically Linux's sys_statfs reports these
481 * fields in units of f_bsize.
482 */
483 buf->f_bsize = dentry->d_sb->s_blocksize;
484 blockbits = dentry->d_sb->s_blocksize_bits;
485 blockres = (1 << blockbits) - 1;
486 buf->f_blocks = (res.tbytes + blockres) >> blockbits;
487 buf->f_bfree = (res.fbytes + blockres) >> blockbits;
488 buf->f_bavail = (res.abytes + blockres) >> blockbits;
489
490 buf->f_files = res.tfiles;
491 buf->f_ffree = res.afiles;
492
493 buf->f_namelen = server->namelen;
494
495 return 0;
496
497 out_err:
498 dprintk("%s: statfs error = %d\n", __func__, -error);
499 return error;
500 }
501 EXPORT_SYMBOL_GPL(nfs_statfs);
502
503 /*
504 * Map the security flavour number to a name
505 */
nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)506 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
507 {
508 static const struct {
509 rpc_authflavor_t flavour;
510 const char *str;
511 } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = {
512 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */
513 { RPC_AUTH_NULL, "null" },
514 { RPC_AUTH_UNIX, "sys" },
515 { RPC_AUTH_GSS_KRB5, "krb5" },
516 { RPC_AUTH_GSS_KRB5I, "krb5i" },
517 { RPC_AUTH_GSS_KRB5P, "krb5p" },
518 { RPC_AUTH_GSS_LKEY, "lkey" },
519 { RPC_AUTH_GSS_LKEYI, "lkeyi" },
520 { RPC_AUTH_GSS_LKEYP, "lkeyp" },
521 { RPC_AUTH_GSS_SPKM, "spkm" },
522 { RPC_AUTH_GSS_SPKMI, "spkmi" },
523 { RPC_AUTH_GSS_SPKMP, "spkmp" },
524 { UINT_MAX, "unknown" }
525 };
526 int i;
527
528 for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
529 if (sec_flavours[i].flavour == flavour)
530 break;
531 }
532 return sec_flavours[i].str;
533 }
534
nfs_show_mountd_netid(struct seq_file * m,struct nfs_server * nfss,int showdefaults)535 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
536 int showdefaults)
537 {
538 struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
539 char *proto = NULL;
540
541 switch (sap->sa_family) {
542 case AF_INET:
543 switch (nfss->mountd_protocol) {
544 case IPPROTO_UDP:
545 proto = RPCBIND_NETID_UDP;
546 break;
547 case IPPROTO_TCP:
548 proto = RPCBIND_NETID_TCP;
549 break;
550 }
551 break;
552 case AF_INET6:
553 switch (nfss->mountd_protocol) {
554 case IPPROTO_UDP:
555 proto = RPCBIND_NETID_UDP6;
556 break;
557 case IPPROTO_TCP:
558 proto = RPCBIND_NETID_TCP6;
559 break;
560 }
561 break;
562 }
563 if (proto || showdefaults)
564 seq_printf(m, ",mountproto=%s", proto ?: "auto");
565 }
566
nfs_show_mountd_options(struct seq_file * m,struct nfs_server * nfss,int showdefaults)567 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
568 int showdefaults)
569 {
570 struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
571
572 if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
573 return;
574
575 switch (sap->sa_family) {
576 case AF_INET: {
577 struct sockaddr_in *sin = (struct sockaddr_in *)sap;
578 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
579 break;
580 }
581 case AF_INET6: {
582 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
583 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
584 break;
585 }
586 default:
587 if (showdefaults)
588 seq_puts(m, ",mountaddr=unspecified");
589 }
590
591 if (nfss->mountd_version || showdefaults)
592 seq_printf(m, ",mountvers=%u", nfss->mountd_version);
593 if ((nfss->mountd_port &&
594 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
595 showdefaults)
596 seq_printf(m, ",mountport=%u", nfss->mountd_port);
597
598 nfs_show_mountd_netid(m, nfss, showdefaults);
599 }
600
601 #if IS_ENABLED(CONFIG_NFS_V4)
nfs_show_nfsv4_options(struct seq_file * m,struct nfs_server * nfss,int showdefaults)602 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
603 int showdefaults)
604 {
605 struct nfs_client *clp = nfss->nfs_client;
606
607 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
608 }
609 #else
nfs_show_nfsv4_options(struct seq_file * m,struct nfs_server * nfss,int showdefaults)610 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
611 int showdefaults)
612 {
613 }
614 #endif
615
nfs_show_nfs_version(struct seq_file * m,unsigned int version,unsigned int minorversion)616 static void nfs_show_nfs_version(struct seq_file *m,
617 unsigned int version,
618 unsigned int minorversion)
619 {
620 seq_printf(m, ",vers=%u", version);
621 if (version == 4)
622 seq_printf(m, ".%u", minorversion);
623 }
624
625 /*
626 * Describe the mount options in force on this server representation
627 */
nfs_show_mount_options(struct seq_file * m,struct nfs_server * nfss,int showdefaults)628 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
629 int showdefaults)
630 {
631 static const struct proc_nfs_info {
632 int flag;
633 const char *str;
634 const char *nostr;
635 } nfs_info[] = {
636 { NFS_MOUNT_SOFT, ",soft", "" },
637 { NFS_MOUNT_SOFTERR, ",softerr", "" },
638 { NFS_MOUNT_POSIX, ",posix", "" },
639 { NFS_MOUNT_NOCTO, ",nocto", "" },
640 { NFS_MOUNT_NOAC, ",noac", "" },
641 { NFS_MOUNT_NONLM, ",nolock", "" },
642 { NFS_MOUNT_NOACL, ",noacl", "" },
643 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
644 { NFS_MOUNT_UNSHARED, ",nosharecache", "" },
645 { NFS_MOUNT_NORESVPORT, ",noresvport", "" },
646 { 0, NULL, NULL }
647 };
648 const struct proc_nfs_info *nfs_infop;
649 struct nfs_client *clp = nfss->nfs_client;
650 u32 version = clp->rpc_ops->version;
651 int local_flock, local_fcntl;
652
653 nfs_show_nfs_version(m, version, clp->cl_minorversion);
654 seq_printf(m, ",rsize=%u", nfss->rsize);
655 seq_printf(m, ",wsize=%u", nfss->wsize);
656 if (nfss->bsize != 0)
657 seq_printf(m, ",bsize=%u", nfss->bsize);
658 seq_printf(m, ",namlen=%u", nfss->namelen);
659 if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
660 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
661 if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
662 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
663 if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
664 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
665 if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
666 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
667 if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR)))
668 seq_puts(m, ",hard");
669 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
670 if (nfss->flags & nfs_infop->flag)
671 seq_puts(m, nfs_infop->str);
672 else
673 seq_puts(m, nfs_infop->nostr);
674 }
675 rcu_read_lock();
676 seq_printf(m, ",proto=%s",
677 rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
678 rcu_read_unlock();
679 if (clp->cl_nconnect > 0)
680 seq_printf(m, ",nconnect=%u", clp->cl_nconnect);
681 if (version == 4) {
682 if (nfss->port != NFS_PORT)
683 seq_printf(m, ",port=%u", nfss->port);
684 } else
685 if (nfss->port)
686 seq_printf(m, ",port=%u", nfss->port);
687
688 seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
689 seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
690 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
691
692 if (version != 4)
693 nfs_show_mountd_options(m, nfss, showdefaults);
694 else
695 nfs_show_nfsv4_options(m, nfss, showdefaults);
696
697 if (nfss->options & NFS_OPTION_FSCACHE)
698 seq_puts(m, ",fsc");
699
700 if (nfss->options & NFS_OPTION_MIGRATION)
701 seq_puts(m, ",migration");
702
703 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
704 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
705 seq_puts(m, ",lookupcache=none");
706 else
707 seq_puts(m, ",lookupcache=pos");
708 }
709
710 local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
711 local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
712
713 if (!local_flock && !local_fcntl)
714 seq_puts(m, ",local_lock=none");
715 else if (local_flock && local_fcntl)
716 seq_puts(m, ",local_lock=all");
717 else if (local_flock)
718 seq_puts(m, ",local_lock=flock");
719 else
720 seq_puts(m, ",local_lock=posix");
721 }
722
723 /*
724 * Describe the mount options on this VFS mountpoint
725 */
nfs_show_options(struct seq_file * m,struct dentry * root)726 int nfs_show_options(struct seq_file *m, struct dentry *root)
727 {
728 struct nfs_server *nfss = NFS_SB(root->d_sb);
729
730 nfs_show_mount_options(m, nfss, 0);
731
732 rcu_read_lock();
733 seq_printf(m, ",addr=%s",
734 rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
735 RPC_DISPLAY_ADDR));
736 rcu_read_unlock();
737
738 return 0;
739 }
740 EXPORT_SYMBOL_GPL(nfs_show_options);
741
742 #if IS_ENABLED(CONFIG_NFS_V4)
show_lease(struct seq_file * m,struct nfs_server * server)743 static void show_lease(struct seq_file *m, struct nfs_server *server)
744 {
745 struct nfs_client *clp = server->nfs_client;
746 unsigned long expire;
747
748 seq_printf(m, ",lease_time=%ld", clp->cl_lease_time / HZ);
749 expire = clp->cl_last_renewal + clp->cl_lease_time;
750 seq_printf(m, ",lease_expired=%ld",
751 time_after(expire, jiffies) ? 0 : (jiffies - expire) / HZ);
752 }
753 #ifdef CONFIG_NFS_V4_1
show_sessions(struct seq_file * m,struct nfs_server * server)754 static void show_sessions(struct seq_file *m, struct nfs_server *server)
755 {
756 if (nfs4_has_session(server->nfs_client))
757 seq_puts(m, ",sessions");
758 }
759 #else
show_sessions(struct seq_file * m,struct nfs_server * server)760 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
761 #endif
762 #endif
763
764 #ifdef CONFIG_NFS_V4_1
show_pnfs(struct seq_file * m,struct nfs_server * server)765 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
766 {
767 seq_printf(m, ",pnfs=");
768 if (server->pnfs_curr_ld)
769 seq_printf(m, "%s", server->pnfs_curr_ld->name);
770 else
771 seq_printf(m, "not configured");
772 }
773
show_implementation_id(struct seq_file * m,struct nfs_server * nfss)774 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
775 {
776 if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
777 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
778 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
779 "date='%llu,%u'",
780 impl_id->name, impl_id->domain,
781 impl_id->date.seconds, impl_id->date.nseconds);
782 }
783 }
784 #else
785 #if IS_ENABLED(CONFIG_NFS_V4)
show_pnfs(struct seq_file * m,struct nfs_server * server)786 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
787 {
788 }
789 #endif
show_implementation_id(struct seq_file * m,struct nfs_server * nfss)790 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
791 {
792 }
793 #endif
794
nfs_show_devname(struct seq_file * m,struct dentry * root)795 int nfs_show_devname(struct seq_file *m, struct dentry *root)
796 {
797 char *page = (char *) __get_free_page(GFP_KERNEL);
798 char *devname, *dummy;
799 int err = 0;
800 if (!page)
801 return -ENOMEM;
802 devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
803 if (IS_ERR(devname))
804 err = PTR_ERR(devname);
805 else
806 seq_escape(m, devname, " \t\n\\");
807 free_page((unsigned long)page);
808 return err;
809 }
810 EXPORT_SYMBOL_GPL(nfs_show_devname);
811
nfs_show_path(struct seq_file * m,struct dentry * dentry)812 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
813 {
814 seq_puts(m, "/");
815 return 0;
816 }
817 EXPORT_SYMBOL_GPL(nfs_show_path);
818
819 /*
820 * Present statistical information for this VFS mountpoint
821 */
nfs_show_stats(struct seq_file * m,struct dentry * root)822 int nfs_show_stats(struct seq_file *m, struct dentry *root)
823 {
824 int i, cpu;
825 struct nfs_server *nfss = NFS_SB(root->d_sb);
826 struct rpc_auth *auth = nfss->client->cl_auth;
827 struct nfs_iostats totals = { };
828
829 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
830
831 /*
832 * Display all mount option settings
833 */
834 seq_puts(m, "\n\topts:\t");
835 seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw");
836 seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : "");
837 seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : "");
838 seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : "");
839 nfs_show_mount_options(m, nfss, 1);
840
841 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
842
843 show_implementation_id(m, nfss);
844
845 seq_puts(m, "\n\tcaps:\t");
846 seq_printf(m, "caps=0x%x", nfss->caps);
847 seq_printf(m, ",wtmult=%u", nfss->wtmult);
848 seq_printf(m, ",dtsize=%u", nfss->dtsize);
849 seq_printf(m, ",bsize=%u", nfss->bsize);
850 seq_printf(m, ",namlen=%u", nfss->namelen);
851
852 #if IS_ENABLED(CONFIG_NFS_V4)
853 if (nfss->nfs_client->rpc_ops->version == 4) {
854 seq_puts(m, "\n\tnfsv4:\t");
855 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
856 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
857 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
858 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
859 show_sessions(m, nfss);
860 show_pnfs(m, nfss);
861 show_lease(m, nfss);
862 }
863 #endif
864
865 /*
866 * Display security flavor in effect for this mount
867 */
868 seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
869 if (auth->au_flavor)
870 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
871
872 /*
873 * Display superblock I/O counters
874 */
875 for_each_possible_cpu(cpu) {
876 struct nfs_iostats *stats;
877
878 preempt_disable();
879 stats = per_cpu_ptr(nfss->io_stats, cpu);
880
881 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
882 totals.events[i] += stats->events[i];
883 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
884 totals.bytes[i] += stats->bytes[i];
885 #ifdef CONFIG_NFS_FSCACHE
886 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
887 totals.fscache[i] += stats->fscache[i];
888 #endif
889
890 preempt_enable();
891 }
892
893 seq_puts(m, "\n\tevents:\t");
894 for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
895 seq_printf(m, "%lu ", totals.events[i]);
896 seq_puts(m, "\n\tbytes:\t");
897 for (i = 0; i < __NFSIOS_BYTESMAX; i++)
898 seq_printf(m, "%Lu ", totals.bytes[i]);
899 #ifdef CONFIG_NFS_FSCACHE
900 if (nfss->options & NFS_OPTION_FSCACHE) {
901 seq_puts(m, "\n\tfsc:\t");
902 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
903 seq_printf(m, "%Lu ", totals.fscache[i]);
904 }
905 #endif
906 seq_putc(m, '\n');
907
908 rpc_clnt_show_stats(m, nfss->client);
909
910 return 0;
911 }
912 EXPORT_SYMBOL_GPL(nfs_show_stats);
913
914 /*
915 * Begin unmount by attempting to remove all automounted mountpoints we added
916 * in response to xdev traversals and referrals
917 */
nfs_umount_begin(struct super_block * sb)918 void nfs_umount_begin(struct super_block *sb)
919 {
920 struct nfs_server *server;
921 struct rpc_clnt *rpc;
922
923 server = NFS_SB(sb);
924 /* -EIO all pending I/O */
925 rpc = server->client_acl;
926 if (!IS_ERR(rpc))
927 rpc_killall_tasks(rpc);
928 rpc = server->client;
929 if (!IS_ERR(rpc))
930 rpc_killall_tasks(rpc);
931 }
932 EXPORT_SYMBOL_GPL(nfs_umount_begin);
933
nfs_alloc_parsed_mount_data(void)934 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
935 {
936 struct nfs_parsed_mount_data *data;
937
938 data = kzalloc(sizeof(*data), GFP_KERNEL);
939 if (data) {
940 data->timeo = NFS_UNSPEC_TIMEO;
941 data->retrans = NFS_UNSPEC_RETRANS;
942 data->acregmin = NFS_DEF_ACREGMIN;
943 data->acregmax = NFS_DEF_ACREGMAX;
944 data->acdirmin = NFS_DEF_ACDIRMIN;
945 data->acdirmax = NFS_DEF_ACDIRMAX;
946 data->mount_server.port = NFS_UNSPEC_PORT;
947 data->nfs_server.port = NFS_UNSPEC_PORT;
948 data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
949 data->selected_flavor = RPC_AUTH_MAXFLAVOR;
950 data->minorversion = 0;
951 data->need_mount = true;
952 data->net = current->nsproxy->net_ns;
953 data->lsm_opts = NULL;
954 }
955 return data;
956 }
957
nfs_free_parsed_mount_data(struct nfs_parsed_mount_data * data)958 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
959 {
960 if (data) {
961 kfree(data->client_address);
962 kfree(data->mount_server.hostname);
963 kfree(data->nfs_server.export_path);
964 kfree(data->nfs_server.hostname);
965 kfree(data->fscache_uniq);
966 security_free_mnt_opts(&data->lsm_opts);
967 kfree(data);
968 }
969 }
970
971 /*
972 * Sanity-check a server address provided by the mount command.
973 *
974 * Address family must be initialized, and address must not be
975 * the ANY address for that family.
976 */
nfs_verify_server_address(struct sockaddr * addr)977 static int nfs_verify_server_address(struct sockaddr *addr)
978 {
979 switch (addr->sa_family) {
980 case AF_INET: {
981 struct sockaddr_in *sa = (struct sockaddr_in *)addr;
982 return sa->sin_addr.s_addr != htonl(INADDR_ANY);
983 }
984 case AF_INET6: {
985 struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
986 return !ipv6_addr_any(sa);
987 }
988 }
989
990 dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
991 return 0;
992 }
993
994 /*
995 * Select between a default port value and a user-specified port value.
996 * If a zero value is set, then autobind will be used.
997 */
nfs_set_port(struct sockaddr * sap,int * port,const unsigned short default_port)998 static void nfs_set_port(struct sockaddr *sap, int *port,
999 const unsigned short default_port)
1000 {
1001 if (*port == NFS_UNSPEC_PORT)
1002 *port = default_port;
1003
1004 rpc_set_port(sap, *port);
1005 }
1006
1007 /*
1008 * Sanity check the NFS transport protocol.
1009 *
1010 */
nfs_validate_transport_protocol(struct nfs_parsed_mount_data * mnt)1011 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
1012 {
1013 switch (mnt->nfs_server.protocol) {
1014 case XPRT_TRANSPORT_UDP:
1015 case XPRT_TRANSPORT_TCP:
1016 case XPRT_TRANSPORT_RDMA:
1017 break;
1018 default:
1019 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1020 }
1021 }
1022
1023 /*
1024 * For text based NFSv2/v3 mounts, the mount protocol transport default
1025 * settings should depend upon the specified NFS transport.
1026 */
nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data * mnt)1027 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1028 {
1029 nfs_validate_transport_protocol(mnt);
1030
1031 if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1032 mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1033 return;
1034 switch (mnt->nfs_server.protocol) {
1035 case XPRT_TRANSPORT_UDP:
1036 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1037 break;
1038 case XPRT_TRANSPORT_TCP:
1039 case XPRT_TRANSPORT_RDMA:
1040 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1041 }
1042 }
1043
1044 /*
1045 * Add 'flavor' to 'auth_info' if not already present.
1046 * Returns true if 'flavor' ends up in the list, false otherwise
1047 */
nfs_auth_info_add(struct nfs_auth_info * auth_info,rpc_authflavor_t flavor)1048 static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
1049 rpc_authflavor_t flavor)
1050 {
1051 unsigned int i;
1052 unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
1053
1054 /* make sure this flavor isn't already in the list */
1055 for (i = 0; i < auth_info->flavor_len; i++) {
1056 if (flavor == auth_info->flavors[i])
1057 return true;
1058 }
1059
1060 if (auth_info->flavor_len + 1 >= max_flavor_len) {
1061 dfprintk(MOUNT, "NFS: too many sec= flavors\n");
1062 return false;
1063 }
1064
1065 auth_info->flavors[auth_info->flavor_len++] = flavor;
1066 return true;
1067 }
1068
1069 /*
1070 * Return true if 'match' is in auth_info or auth_info is empty.
1071 * Return false otherwise.
1072 */
nfs_auth_info_match(const struct nfs_auth_info * auth_info,rpc_authflavor_t match)1073 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info,
1074 rpc_authflavor_t match)
1075 {
1076 int i;
1077
1078 if (!auth_info->flavor_len)
1079 return true;
1080
1081 for (i = 0; i < auth_info->flavor_len; i++) {
1082 if (auth_info->flavors[i] == match)
1083 return true;
1084 }
1085 return false;
1086 }
1087 EXPORT_SYMBOL_GPL(nfs_auth_info_match);
1088
1089 /*
1090 * Parse the value of the 'sec=' option.
1091 */
nfs_parse_security_flavors(char * value,struct nfs_parsed_mount_data * mnt)1092 static int nfs_parse_security_flavors(char *value,
1093 struct nfs_parsed_mount_data *mnt)
1094 {
1095 substring_t args[MAX_OPT_ARGS];
1096 rpc_authflavor_t pseudoflavor;
1097 char *p;
1098
1099 dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1100
1101 while ((p = strsep(&value, ":")) != NULL) {
1102 switch (match_token(p, nfs_secflavor_tokens, args)) {
1103 case Opt_sec_none:
1104 pseudoflavor = RPC_AUTH_NULL;
1105 break;
1106 case Opt_sec_sys:
1107 pseudoflavor = RPC_AUTH_UNIX;
1108 break;
1109 case Opt_sec_krb5:
1110 pseudoflavor = RPC_AUTH_GSS_KRB5;
1111 break;
1112 case Opt_sec_krb5i:
1113 pseudoflavor = RPC_AUTH_GSS_KRB5I;
1114 break;
1115 case Opt_sec_krb5p:
1116 pseudoflavor = RPC_AUTH_GSS_KRB5P;
1117 break;
1118 case Opt_sec_lkey:
1119 pseudoflavor = RPC_AUTH_GSS_LKEY;
1120 break;
1121 case Opt_sec_lkeyi:
1122 pseudoflavor = RPC_AUTH_GSS_LKEYI;
1123 break;
1124 case Opt_sec_lkeyp:
1125 pseudoflavor = RPC_AUTH_GSS_LKEYP;
1126 break;
1127 case Opt_sec_spkm:
1128 pseudoflavor = RPC_AUTH_GSS_SPKM;
1129 break;
1130 case Opt_sec_spkmi:
1131 pseudoflavor = RPC_AUTH_GSS_SPKMI;
1132 break;
1133 case Opt_sec_spkmp:
1134 pseudoflavor = RPC_AUTH_GSS_SPKMP;
1135 break;
1136 default:
1137 dfprintk(MOUNT,
1138 "NFS: sec= option '%s' not recognized\n", p);
1139 return 0;
1140 }
1141
1142 if (!nfs_auth_info_add(&mnt->auth_info, pseudoflavor))
1143 return 0;
1144 }
1145
1146 return 1;
1147 }
1148
nfs_parse_version_string(char * string,struct nfs_parsed_mount_data * mnt,substring_t * args)1149 static int nfs_parse_version_string(char *string,
1150 struct nfs_parsed_mount_data *mnt,
1151 substring_t *args)
1152 {
1153 mnt->flags &= ~NFS_MOUNT_VER3;
1154 switch (match_token(string, nfs_vers_tokens, args)) {
1155 case Opt_vers_2:
1156 mnt->version = 2;
1157 break;
1158 case Opt_vers_3:
1159 mnt->flags |= NFS_MOUNT_VER3;
1160 mnt->version = 3;
1161 break;
1162 case Opt_vers_4:
1163 /* Backward compatibility option. In future,
1164 * the mount program should always supply
1165 * a NFSv4 minor version number.
1166 */
1167 mnt->version = 4;
1168 break;
1169 case Opt_vers_4_0:
1170 mnt->version = 4;
1171 mnt->minorversion = 0;
1172 break;
1173 case Opt_vers_4_1:
1174 mnt->version = 4;
1175 mnt->minorversion = 1;
1176 break;
1177 case Opt_vers_4_2:
1178 mnt->version = 4;
1179 mnt->minorversion = 2;
1180 break;
1181 default:
1182 return 0;
1183 }
1184 return 1;
1185 }
1186
nfs_get_option_str(substring_t args[],char ** option)1187 static int nfs_get_option_str(substring_t args[], char **option)
1188 {
1189 kfree(*option);
1190 *option = match_strdup(args);
1191 return !*option;
1192 }
1193
nfs_get_option_ul(substring_t args[],unsigned long * option)1194 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1195 {
1196 int rc;
1197 char *string;
1198
1199 string = match_strdup(args);
1200 if (string == NULL)
1201 return -ENOMEM;
1202 rc = kstrtoul(string, 10, option);
1203 kfree(string);
1204
1205 return rc;
1206 }
1207
nfs_get_option_ul_bound(substring_t args[],unsigned long * option,unsigned long l_bound,unsigned long u_bound)1208 static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
1209 unsigned long l_bound, unsigned long u_bound)
1210 {
1211 int ret;
1212
1213 ret = nfs_get_option_ul(args, option);
1214 if (ret != 0)
1215 return ret;
1216 if (*option < l_bound || *option > u_bound)
1217 return -ERANGE;
1218 return 0;
1219 }
1220
1221 /*
1222 * Error-check and convert a string of mount options from user space into
1223 * a data structure. The whole mount string is processed; bad options are
1224 * skipped as they are encountered. If there were no errors, return 1;
1225 * otherwise return 0 (zero).
1226 */
nfs_parse_mount_options(char * raw,struct nfs_parsed_mount_data * mnt)1227 static int nfs_parse_mount_options(char *raw,
1228 struct nfs_parsed_mount_data *mnt)
1229 {
1230 char *p, *string;
1231 int rc, sloppy = 0, invalid_option = 0;
1232 unsigned short protofamily = AF_UNSPEC;
1233 unsigned short mountfamily = AF_UNSPEC;
1234
1235 if (!raw) {
1236 dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1237 return 1;
1238 }
1239 dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1240
1241 rc = security_sb_eat_lsm_opts(raw, &mnt->lsm_opts);
1242 if (rc)
1243 goto out_security_failure;
1244
1245 while ((p = strsep(&raw, ",")) != NULL) {
1246 substring_t args[MAX_OPT_ARGS];
1247 unsigned long option;
1248 int token;
1249
1250 if (!*p)
1251 continue;
1252
1253 dfprintk(MOUNT, "NFS: parsing nfs mount option '%s'\n", p);
1254
1255 token = match_token(p, nfs_mount_option_tokens, args);
1256 switch (token) {
1257
1258 /*
1259 * boolean options: foo/nofoo
1260 */
1261 case Opt_soft:
1262 mnt->flags |= NFS_MOUNT_SOFT;
1263 mnt->flags &= ~NFS_MOUNT_SOFTERR;
1264 break;
1265 case Opt_softerr:
1266 mnt->flags |= NFS_MOUNT_SOFTERR;
1267 mnt->flags &= ~NFS_MOUNT_SOFT;
1268 break;
1269 case Opt_hard:
1270 mnt->flags &= ~(NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR);
1271 break;
1272 case Opt_posix:
1273 mnt->flags |= NFS_MOUNT_POSIX;
1274 break;
1275 case Opt_noposix:
1276 mnt->flags &= ~NFS_MOUNT_POSIX;
1277 break;
1278 case Opt_cto:
1279 mnt->flags &= ~NFS_MOUNT_NOCTO;
1280 break;
1281 case Opt_nocto:
1282 mnt->flags |= NFS_MOUNT_NOCTO;
1283 break;
1284 case Opt_ac:
1285 mnt->flags &= ~NFS_MOUNT_NOAC;
1286 break;
1287 case Opt_noac:
1288 mnt->flags |= NFS_MOUNT_NOAC;
1289 break;
1290 case Opt_lock:
1291 mnt->flags &= ~NFS_MOUNT_NONLM;
1292 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1293 NFS_MOUNT_LOCAL_FCNTL);
1294 break;
1295 case Opt_nolock:
1296 mnt->flags |= NFS_MOUNT_NONLM;
1297 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1298 NFS_MOUNT_LOCAL_FCNTL);
1299 break;
1300 case Opt_udp:
1301 mnt->flags &= ~NFS_MOUNT_TCP;
1302 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1303 break;
1304 case Opt_tcp:
1305 mnt->flags |= NFS_MOUNT_TCP;
1306 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1307 break;
1308 case Opt_rdma:
1309 mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1310 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1311 xprt_load_transport(p);
1312 break;
1313 case Opt_acl:
1314 mnt->flags &= ~NFS_MOUNT_NOACL;
1315 break;
1316 case Opt_noacl:
1317 mnt->flags |= NFS_MOUNT_NOACL;
1318 break;
1319 case Opt_rdirplus:
1320 mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1321 break;
1322 case Opt_nordirplus:
1323 mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1324 break;
1325 case Opt_sharecache:
1326 mnt->flags &= ~NFS_MOUNT_UNSHARED;
1327 break;
1328 case Opt_nosharecache:
1329 mnt->flags |= NFS_MOUNT_UNSHARED;
1330 break;
1331 case Opt_resvport:
1332 mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1333 break;
1334 case Opt_noresvport:
1335 mnt->flags |= NFS_MOUNT_NORESVPORT;
1336 break;
1337 case Opt_fscache:
1338 mnt->options |= NFS_OPTION_FSCACHE;
1339 kfree(mnt->fscache_uniq);
1340 mnt->fscache_uniq = NULL;
1341 break;
1342 case Opt_nofscache:
1343 mnt->options &= ~NFS_OPTION_FSCACHE;
1344 kfree(mnt->fscache_uniq);
1345 mnt->fscache_uniq = NULL;
1346 break;
1347 case Opt_migration:
1348 mnt->options |= NFS_OPTION_MIGRATION;
1349 break;
1350 case Opt_nomigration:
1351 mnt->options &= ~NFS_OPTION_MIGRATION;
1352 break;
1353
1354 /*
1355 * options that take numeric values
1356 */
1357 case Opt_port:
1358 if (nfs_get_option_ul(args, &option) ||
1359 option > USHRT_MAX)
1360 goto out_invalid_value;
1361 mnt->nfs_server.port = option;
1362 break;
1363 case Opt_rsize:
1364 if (nfs_get_option_ul(args, &option))
1365 goto out_invalid_value;
1366 mnt->rsize = option;
1367 break;
1368 case Opt_wsize:
1369 if (nfs_get_option_ul(args, &option))
1370 goto out_invalid_value;
1371 mnt->wsize = option;
1372 break;
1373 case Opt_bsize:
1374 if (nfs_get_option_ul(args, &option))
1375 goto out_invalid_value;
1376 mnt->bsize = option;
1377 break;
1378 case Opt_timeo:
1379 if (nfs_get_option_ul_bound(args, &option, 1, INT_MAX))
1380 goto out_invalid_value;
1381 mnt->timeo = option;
1382 break;
1383 case Opt_retrans:
1384 if (nfs_get_option_ul_bound(args, &option, 0, INT_MAX))
1385 goto out_invalid_value;
1386 mnt->retrans = option;
1387 break;
1388 case Opt_acregmin:
1389 if (nfs_get_option_ul(args, &option))
1390 goto out_invalid_value;
1391 mnt->acregmin = option;
1392 break;
1393 case Opt_acregmax:
1394 if (nfs_get_option_ul(args, &option))
1395 goto out_invalid_value;
1396 mnt->acregmax = option;
1397 break;
1398 case Opt_acdirmin:
1399 if (nfs_get_option_ul(args, &option))
1400 goto out_invalid_value;
1401 mnt->acdirmin = option;
1402 break;
1403 case Opt_acdirmax:
1404 if (nfs_get_option_ul(args, &option))
1405 goto out_invalid_value;
1406 mnt->acdirmax = option;
1407 break;
1408 case Opt_actimeo:
1409 if (nfs_get_option_ul(args, &option))
1410 goto out_invalid_value;
1411 mnt->acregmin = mnt->acregmax =
1412 mnt->acdirmin = mnt->acdirmax = option;
1413 break;
1414 case Opt_namelen:
1415 if (nfs_get_option_ul(args, &option))
1416 goto out_invalid_value;
1417 mnt->namlen = option;
1418 break;
1419 case Opt_mountport:
1420 if (nfs_get_option_ul(args, &option) ||
1421 option > USHRT_MAX)
1422 goto out_invalid_value;
1423 mnt->mount_server.port = option;
1424 break;
1425 case Opt_mountvers:
1426 if (nfs_get_option_ul(args, &option) ||
1427 option < NFS_MNT_VERSION ||
1428 option > NFS_MNT3_VERSION)
1429 goto out_invalid_value;
1430 mnt->mount_server.version = option;
1431 break;
1432 case Opt_minorversion:
1433 if (nfs_get_option_ul(args, &option))
1434 goto out_invalid_value;
1435 if (option > NFS4_MAX_MINOR_VERSION)
1436 goto out_invalid_value;
1437 mnt->minorversion = option;
1438 break;
1439
1440 /*
1441 * options that take text values
1442 */
1443 case Opt_nfsvers:
1444 string = match_strdup(args);
1445 if (string == NULL)
1446 goto out_nomem;
1447 rc = nfs_parse_version_string(string, mnt, args);
1448 kfree(string);
1449 if (!rc)
1450 goto out_invalid_value;
1451 break;
1452 case Opt_sec:
1453 string = match_strdup(args);
1454 if (string == NULL)
1455 goto out_nomem;
1456 rc = nfs_parse_security_flavors(string, mnt);
1457 kfree(string);
1458 if (!rc) {
1459 dfprintk(MOUNT, "NFS: unrecognized "
1460 "security flavor\n");
1461 return 0;
1462 }
1463 break;
1464 case Opt_proto:
1465 string = match_strdup(args);
1466 if (string == NULL)
1467 goto out_nomem;
1468 token = match_token(string,
1469 nfs_xprt_protocol_tokens, args);
1470
1471 protofamily = AF_INET;
1472 switch (token) {
1473 case Opt_xprt_udp6:
1474 protofamily = AF_INET6;
1475 /* fall through */
1476 case Opt_xprt_udp:
1477 mnt->flags &= ~NFS_MOUNT_TCP;
1478 mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1479 break;
1480 case Opt_xprt_tcp6:
1481 protofamily = AF_INET6;
1482 /* fall through */
1483 case Opt_xprt_tcp:
1484 mnt->flags |= NFS_MOUNT_TCP;
1485 mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1486 break;
1487 case Opt_xprt_rdma6:
1488 protofamily = AF_INET6;
1489 /* fall through */
1490 case Opt_xprt_rdma:
1491 /* vector side protocols to TCP */
1492 mnt->flags |= NFS_MOUNT_TCP;
1493 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1494 xprt_load_transport(string);
1495 break;
1496 default:
1497 dfprintk(MOUNT, "NFS: unrecognized "
1498 "transport protocol\n");
1499 kfree(string);
1500 return 0;
1501 }
1502 kfree(string);
1503 break;
1504 case Opt_mountproto:
1505 string = match_strdup(args);
1506 if (string == NULL)
1507 goto out_nomem;
1508 token = match_token(string,
1509 nfs_xprt_protocol_tokens, args);
1510 kfree(string);
1511
1512 mountfamily = AF_INET;
1513 switch (token) {
1514 case Opt_xprt_udp6:
1515 mountfamily = AF_INET6;
1516 /* fall through */
1517 case Opt_xprt_udp:
1518 mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1519 break;
1520 case Opt_xprt_tcp6:
1521 mountfamily = AF_INET6;
1522 /* fall through */
1523 case Opt_xprt_tcp:
1524 mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1525 break;
1526 case Opt_xprt_rdma: /* not used for side protocols */
1527 default:
1528 dfprintk(MOUNT, "NFS: unrecognized "
1529 "transport protocol\n");
1530 return 0;
1531 }
1532 break;
1533 case Opt_addr:
1534 string = match_strdup(args);
1535 if (string == NULL)
1536 goto out_nomem;
1537 mnt->nfs_server.addrlen =
1538 rpc_pton(mnt->net, string, strlen(string),
1539 (struct sockaddr *)
1540 &mnt->nfs_server.address,
1541 sizeof(mnt->nfs_server.address));
1542 kfree(string);
1543 if (mnt->nfs_server.addrlen == 0)
1544 goto out_invalid_address;
1545 break;
1546 case Opt_clientaddr:
1547 if (nfs_get_option_str(args, &mnt->client_address))
1548 goto out_nomem;
1549 break;
1550 case Opt_mounthost:
1551 if (nfs_get_option_str(args,
1552 &mnt->mount_server.hostname))
1553 goto out_nomem;
1554 break;
1555 case Opt_mountaddr:
1556 string = match_strdup(args);
1557 if (string == NULL)
1558 goto out_nomem;
1559 mnt->mount_server.addrlen =
1560 rpc_pton(mnt->net, string, strlen(string),
1561 (struct sockaddr *)
1562 &mnt->mount_server.address,
1563 sizeof(mnt->mount_server.address));
1564 kfree(string);
1565 if (mnt->mount_server.addrlen == 0)
1566 goto out_invalid_address;
1567 break;
1568 case Opt_nconnect:
1569 if (nfs_get_option_ul_bound(args, &option, 1, NFS_MAX_CONNECTIONS))
1570 goto out_invalid_value;
1571 mnt->nfs_server.nconnect = option;
1572 break;
1573 case Opt_lookupcache:
1574 string = match_strdup(args);
1575 if (string == NULL)
1576 goto out_nomem;
1577 token = match_token(string,
1578 nfs_lookupcache_tokens, args);
1579 kfree(string);
1580 switch (token) {
1581 case Opt_lookupcache_all:
1582 mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1583 break;
1584 case Opt_lookupcache_positive:
1585 mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1586 mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1587 break;
1588 case Opt_lookupcache_none:
1589 mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1590 break;
1591 default:
1592 dfprintk(MOUNT, "NFS: invalid "
1593 "lookupcache argument\n");
1594 return 0;
1595 };
1596 break;
1597 case Opt_fscache_uniq:
1598 if (nfs_get_option_str(args, &mnt->fscache_uniq))
1599 goto out_nomem;
1600 mnt->options |= NFS_OPTION_FSCACHE;
1601 break;
1602 case Opt_local_lock:
1603 string = match_strdup(args);
1604 if (string == NULL)
1605 goto out_nomem;
1606 token = match_token(string, nfs_local_lock_tokens,
1607 args);
1608 kfree(string);
1609 switch (token) {
1610 case Opt_local_lock_all:
1611 mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1612 NFS_MOUNT_LOCAL_FCNTL);
1613 break;
1614 case Opt_local_lock_flock:
1615 mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1616 break;
1617 case Opt_local_lock_posix:
1618 mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1619 break;
1620 case Opt_local_lock_none:
1621 mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1622 NFS_MOUNT_LOCAL_FCNTL);
1623 break;
1624 default:
1625 dfprintk(MOUNT, "NFS: invalid "
1626 "local_lock argument\n");
1627 return 0;
1628 };
1629 break;
1630
1631 /*
1632 * Special options
1633 */
1634 case Opt_sloppy:
1635 sloppy = 1;
1636 dfprintk(MOUNT, "NFS: relaxing parsing rules\n");
1637 break;
1638 case Opt_userspace:
1639 case Opt_deprecated:
1640 dfprintk(MOUNT, "NFS: ignoring mount option "
1641 "'%s'\n", p);
1642 break;
1643
1644 default:
1645 invalid_option = 1;
1646 dfprintk(MOUNT, "NFS: unrecognized mount option "
1647 "'%s'\n", p);
1648 }
1649 }
1650
1651 if (!sloppy && invalid_option)
1652 return 0;
1653
1654 if (mnt->minorversion && mnt->version != 4)
1655 goto out_minorversion_mismatch;
1656
1657 if (mnt->options & NFS_OPTION_MIGRATION &&
1658 (mnt->version != 4 || mnt->minorversion != 0))
1659 goto out_migration_misuse;
1660
1661 /*
1662 * verify that any proto=/mountproto= options match the address
1663 * families in the addr=/mountaddr= options.
1664 */
1665 if (protofamily != AF_UNSPEC &&
1666 protofamily != mnt->nfs_server.address.ss_family)
1667 goto out_proto_mismatch;
1668
1669 if (mountfamily != AF_UNSPEC) {
1670 if (mnt->mount_server.addrlen) {
1671 if (mountfamily != mnt->mount_server.address.ss_family)
1672 goto out_mountproto_mismatch;
1673 } else {
1674 if (mountfamily != mnt->nfs_server.address.ss_family)
1675 goto out_mountproto_mismatch;
1676 }
1677 }
1678
1679 return 1;
1680
1681 out_mountproto_mismatch:
1682 printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1683 "option\n");
1684 return 0;
1685 out_proto_mismatch:
1686 printk(KERN_INFO "NFS: server address does not match proto= option\n");
1687 return 0;
1688 out_invalid_address:
1689 printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1690 return 0;
1691 out_invalid_value:
1692 printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1693 return 0;
1694 out_minorversion_mismatch:
1695 printk(KERN_INFO "NFS: mount option vers=%u does not support "
1696 "minorversion=%u\n", mnt->version, mnt->minorversion);
1697 return 0;
1698 out_migration_misuse:
1699 printk(KERN_INFO
1700 "NFS: 'migration' not supported for this NFS version\n");
1701 return 0;
1702 out_nomem:
1703 printk(KERN_INFO "NFS: not enough memory to parse option\n");
1704 return 0;
1705 out_security_failure:
1706 printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1707 return 0;
1708 }
1709
1710 /*
1711 * Ensure that a specified authtype in args->auth_info is supported by
1712 * the server. Returns 0 and sets args->selected_flavor if it's ok, and
1713 * -EACCES if not.
1714 */
nfs_verify_authflavors(struct nfs_parsed_mount_data * args,rpc_authflavor_t * server_authlist,unsigned int count)1715 static int nfs_verify_authflavors(struct nfs_parsed_mount_data *args,
1716 rpc_authflavor_t *server_authlist, unsigned int count)
1717 {
1718 rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR;
1719 bool found_auth_null = false;
1720 unsigned int i;
1721
1722 /*
1723 * If the sec= mount option is used, the specified flavor or AUTH_NULL
1724 * must be in the list returned by the server.
1725 *
1726 * AUTH_NULL has a special meaning when it's in the server list - it
1727 * means that the server will ignore the rpc creds, so any flavor
1728 * can be used but still use the sec= that was specified.
1729 *
1730 * Note also that the MNT procedure in MNTv1 does not return a list
1731 * of supported security flavors. In this case, nfs_mount() fabricates
1732 * a security flavor list containing just AUTH_NULL.
1733 */
1734 for (i = 0; i < count; i++) {
1735 flavor = server_authlist[i];
1736
1737 if (nfs_auth_info_match(&args->auth_info, flavor))
1738 goto out;
1739
1740 if (flavor == RPC_AUTH_NULL)
1741 found_auth_null = true;
1742 }
1743
1744 if (found_auth_null) {
1745 flavor = args->auth_info.flavors[0];
1746 goto out;
1747 }
1748
1749 dfprintk(MOUNT,
1750 "NFS: specified auth flavors not supported by server\n");
1751 return -EACCES;
1752
1753 out:
1754 args->selected_flavor = flavor;
1755 dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->selected_flavor);
1756 return 0;
1757 }
1758
1759 /*
1760 * Use the remote server's MOUNT service to request the NFS file handle
1761 * corresponding to the provided path.
1762 */
nfs_request_mount(struct nfs_parsed_mount_data * args,struct nfs_fh * root_fh,rpc_authflavor_t * server_authlist,unsigned int * server_authlist_len)1763 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1764 struct nfs_fh *root_fh,
1765 rpc_authflavor_t *server_authlist,
1766 unsigned int *server_authlist_len)
1767 {
1768 struct nfs_mount_request request = {
1769 .sap = (struct sockaddr *)
1770 &args->mount_server.address,
1771 .dirpath = args->nfs_server.export_path,
1772 .protocol = args->mount_server.protocol,
1773 .fh = root_fh,
1774 .noresvport = args->flags & NFS_MOUNT_NORESVPORT,
1775 .auth_flav_len = server_authlist_len,
1776 .auth_flavs = server_authlist,
1777 .net = args->net,
1778 };
1779 int status;
1780
1781 if (args->mount_server.version == 0) {
1782 switch (args->version) {
1783 default:
1784 args->mount_server.version = NFS_MNT3_VERSION;
1785 break;
1786 case 2:
1787 args->mount_server.version = NFS_MNT_VERSION;
1788 }
1789 }
1790 request.version = args->mount_server.version;
1791
1792 if (args->mount_server.hostname)
1793 request.hostname = args->mount_server.hostname;
1794 else
1795 request.hostname = args->nfs_server.hostname;
1796
1797 /*
1798 * Construct the mount server's address.
1799 */
1800 if (args->mount_server.address.ss_family == AF_UNSPEC) {
1801 memcpy(request.sap, &args->nfs_server.address,
1802 args->nfs_server.addrlen);
1803 args->mount_server.addrlen = args->nfs_server.addrlen;
1804 }
1805 request.salen = args->mount_server.addrlen;
1806 nfs_set_port(request.sap, &args->mount_server.port, 0);
1807
1808 /*
1809 * Now ask the mount server to map our export path
1810 * to a file handle.
1811 */
1812 status = nfs_mount(&request);
1813 if (status != 0) {
1814 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1815 request.hostname, status);
1816 return status;
1817 }
1818
1819 return 0;
1820 }
1821
nfs_try_mount_request(struct nfs_mount_info * mount_info,struct nfs_subversion * nfs_mod)1822 static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1823 struct nfs_subversion *nfs_mod)
1824 {
1825 int status;
1826 unsigned int i;
1827 bool tried_auth_unix = false;
1828 bool auth_null_in_list = false;
1829 struct nfs_server *server = ERR_PTR(-EACCES);
1830 struct nfs_parsed_mount_data *args = mount_info->parsed;
1831 rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1832 unsigned int authlist_len = ARRAY_SIZE(authlist);
1833
1834 status = nfs_request_mount(args, mount_info->mntfh, authlist,
1835 &authlist_len);
1836 if (status)
1837 return ERR_PTR(status);
1838
1839 /*
1840 * Was a sec= authflavor specified in the options? First, verify
1841 * whether the server supports it, and then just try to use it if so.
1842 */
1843 if (args->auth_info.flavor_len > 0) {
1844 status = nfs_verify_authflavors(args, authlist, authlist_len);
1845 dfprintk(MOUNT, "NFS: using auth flavor %u\n",
1846 args->selected_flavor);
1847 if (status)
1848 return ERR_PTR(status);
1849 return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1850 }
1851
1852 /*
1853 * No sec= option was provided. RFC 2623, section 2.7 suggests we
1854 * SHOULD prefer the flavor listed first. However, some servers list
1855 * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1856 */
1857 for (i = 0; i < authlist_len; ++i) {
1858 rpc_authflavor_t flavor;
1859 struct rpcsec_gss_info info;
1860
1861 flavor = authlist[i];
1862 switch (flavor) {
1863 case RPC_AUTH_UNIX:
1864 tried_auth_unix = true;
1865 break;
1866 case RPC_AUTH_NULL:
1867 auth_null_in_list = true;
1868 continue;
1869 default:
1870 if (rpcauth_get_gssinfo(flavor, &info) != 0)
1871 continue;
1872 /* Fallthrough */
1873 }
1874 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1875 args->selected_flavor = flavor;
1876 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1877 if (!IS_ERR(server))
1878 return server;
1879 }
1880
1881 /*
1882 * Nothing we tried so far worked. At this point, give up if we've
1883 * already tried AUTH_UNIX or if the server's list doesn't contain
1884 * AUTH_NULL
1885 */
1886 if (tried_auth_unix || !auth_null_in_list)
1887 return server;
1888
1889 /* Last chance! Try AUTH_UNIX */
1890 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1891 args->selected_flavor = RPC_AUTH_UNIX;
1892 return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1893 }
1894
nfs_try_mount(int flags,const char * dev_name,struct nfs_mount_info * mount_info,struct nfs_subversion * nfs_mod)1895 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1896 struct nfs_mount_info *mount_info,
1897 struct nfs_subversion *nfs_mod)
1898 {
1899 struct nfs_server *server;
1900
1901 if (mount_info->parsed->need_mount)
1902 server = nfs_try_mount_request(mount_info, nfs_mod);
1903 else
1904 server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1905
1906 if (IS_ERR(server))
1907 return ERR_CAST(server);
1908
1909 return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1910 }
1911 EXPORT_SYMBOL_GPL(nfs_try_mount);
1912
1913 /*
1914 * Split "dev_name" into "hostname:export_path".
1915 *
1916 * The leftmost colon demarks the split between the server's hostname
1917 * and the export path. If the hostname starts with a left square
1918 * bracket, then it may contain colons.
1919 *
1920 * Note: caller frees hostname and export path, even on error.
1921 */
nfs_parse_devname(const char * dev_name,char ** hostname,size_t maxnamlen,char ** export_path,size_t maxpathlen)1922 static int nfs_parse_devname(const char *dev_name,
1923 char **hostname, size_t maxnamlen,
1924 char **export_path, size_t maxpathlen)
1925 {
1926 size_t len;
1927 char *end;
1928
1929 if (unlikely(!dev_name || !*dev_name)) {
1930 dfprintk(MOUNT, "NFS: device name not specified\n");
1931 return -EINVAL;
1932 }
1933
1934 /* Is the host name protected with square brakcets? */
1935 if (*dev_name == '[') {
1936 end = strchr(++dev_name, ']');
1937 if (end == NULL || end[1] != ':')
1938 goto out_bad_devname;
1939
1940 len = end - dev_name;
1941 end++;
1942 } else {
1943 char *comma;
1944
1945 end = strchr(dev_name, ':');
1946 if (end == NULL)
1947 goto out_bad_devname;
1948 len = end - dev_name;
1949
1950 /* kill possible hostname list: not supported */
1951 comma = strchr(dev_name, ',');
1952 if (comma != NULL && comma < end)
1953 len = comma - dev_name;
1954 }
1955
1956 if (len > maxnamlen)
1957 goto out_hostname;
1958
1959 /* N.B. caller will free nfs_server.hostname in all cases */
1960 *hostname = kstrndup(dev_name, len, GFP_KERNEL);
1961 if (*hostname == NULL)
1962 goto out_nomem;
1963 len = strlen(++end);
1964 if (len > maxpathlen)
1965 goto out_path;
1966 *export_path = kstrndup(end, len, GFP_KERNEL);
1967 if (!*export_path)
1968 goto out_nomem;
1969
1970 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1971 return 0;
1972
1973 out_bad_devname:
1974 dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1975 return -EINVAL;
1976
1977 out_nomem:
1978 dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1979 return -ENOMEM;
1980
1981 out_hostname:
1982 dfprintk(MOUNT, "NFS: server hostname too long\n");
1983 return -ENAMETOOLONG;
1984
1985 out_path:
1986 dfprintk(MOUNT, "NFS: export pathname too long\n");
1987 return -ENAMETOOLONG;
1988 }
1989
1990 /*
1991 * Validate the NFS2/NFS3 mount data
1992 * - fills in the mount root filehandle
1993 *
1994 * For option strings, user space handles the following behaviors:
1995 *
1996 * + DNS: mapping server host name to IP address ("addr=" option)
1997 *
1998 * + failure mode: how to behave if a mount request can't be handled
1999 * immediately ("fg/bg" option)
2000 *
2001 * + retry: how often to retry a mount request ("retry=" option)
2002 *
2003 * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
2004 * mountproto=tcp after mountproto=udp, and so on
2005 */
nfs23_validate_mount_data(void * options,struct nfs_parsed_mount_data * args,struct nfs_fh * mntfh,const char * dev_name)2006 static int nfs23_validate_mount_data(void *options,
2007 struct nfs_parsed_mount_data *args,
2008 struct nfs_fh *mntfh,
2009 const char *dev_name)
2010 {
2011 struct nfs_mount_data *data = (struct nfs_mount_data *)options;
2012 struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2013 int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
2014
2015 if (data == NULL)
2016 goto out_no_data;
2017
2018 args->version = NFS_DEFAULT_VERSION;
2019 switch (data->version) {
2020 case 1:
2021 data->namlen = 0; /* fall through */
2022 case 2:
2023 data->bsize = 0; /* fall through */
2024 case 3:
2025 if (data->flags & NFS_MOUNT_VER3)
2026 goto out_no_v3;
2027 data->root.size = NFS2_FHSIZE;
2028 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
2029 /* Turn off security negotiation */
2030 extra_flags |= NFS_MOUNT_SECFLAVOUR;
2031 /* fall through */
2032 case 4:
2033 if (data->flags & NFS_MOUNT_SECFLAVOUR)
2034 goto out_no_sec;
2035 /* fall through */
2036 case 5:
2037 memset(data->context, 0, sizeof(data->context));
2038 /* fall through */
2039 case 6:
2040 if (data->flags & NFS_MOUNT_VER3) {
2041 if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
2042 goto out_invalid_fh;
2043 mntfh->size = data->root.size;
2044 args->version = 3;
2045 } else {
2046 mntfh->size = NFS2_FHSIZE;
2047 args->version = 2;
2048 }
2049
2050
2051 memcpy(mntfh->data, data->root.data, mntfh->size);
2052 if (mntfh->size < sizeof(mntfh->data))
2053 memset(mntfh->data + mntfh->size, 0,
2054 sizeof(mntfh->data) - mntfh->size);
2055
2056 /*
2057 * Translate to nfs_parsed_mount_data, which nfs_fill_super
2058 * can deal with.
2059 */
2060 args->flags = data->flags & NFS_MOUNT_FLAGMASK;
2061 args->flags |= extra_flags;
2062 args->rsize = data->rsize;
2063 args->wsize = data->wsize;
2064 args->timeo = data->timeo;
2065 args->retrans = data->retrans;
2066 args->acregmin = data->acregmin;
2067 args->acregmax = data->acregmax;
2068 args->acdirmin = data->acdirmin;
2069 args->acdirmax = data->acdirmax;
2070 args->need_mount = false;
2071
2072 memcpy(sap, &data->addr, sizeof(data->addr));
2073 args->nfs_server.addrlen = sizeof(data->addr);
2074 args->nfs_server.port = ntohs(data->addr.sin_port);
2075 if (sap->sa_family != AF_INET ||
2076 !nfs_verify_server_address(sap))
2077 goto out_no_address;
2078
2079 if (!(data->flags & NFS_MOUNT_TCP))
2080 args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
2081 /* N.B. caller will free nfs_server.hostname in all cases */
2082 args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
2083 args->namlen = data->namlen;
2084 args->bsize = data->bsize;
2085
2086 if (data->flags & NFS_MOUNT_SECFLAVOUR)
2087 args->selected_flavor = data->pseudoflavor;
2088 else
2089 args->selected_flavor = RPC_AUTH_UNIX;
2090 if (!args->nfs_server.hostname)
2091 goto out_nomem;
2092
2093 if (!(data->flags & NFS_MOUNT_NONLM))
2094 args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
2095 NFS_MOUNT_LOCAL_FCNTL);
2096 else
2097 args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
2098 NFS_MOUNT_LOCAL_FCNTL);
2099 /*
2100 * The legacy version 6 binary mount data from userspace has a
2101 * field used only to transport selinux information into the
2102 * the kernel. To continue to support that functionality we
2103 * have a touch of selinux knowledge here in the NFS code. The
2104 * userspace code converted context=blah to just blah so we are
2105 * converting back to the full string selinux understands.
2106 */
2107 if (data->context[0]){
2108 #ifdef CONFIG_SECURITY_SELINUX
2109 int rc;
2110 data->context[NFS_MAX_CONTEXT_LEN] = '\0';
2111 rc = security_add_mnt_opt("context", data->context,
2112 strlen(data->context), &args->lsm_opts);
2113 if (rc)
2114 return rc;
2115 #else
2116 return -EINVAL;
2117 #endif
2118 }
2119
2120 break;
2121 default:
2122 return NFS_TEXT_DATA;
2123 }
2124
2125 return 0;
2126
2127 out_no_data:
2128 dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2129 return -EINVAL;
2130
2131 out_no_v3:
2132 dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2133 data->version);
2134 return -EINVAL;
2135
2136 out_no_sec:
2137 dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2138 return -EINVAL;
2139
2140 out_nomem:
2141 dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2142 return -ENOMEM;
2143
2144 out_no_address:
2145 dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2146 return -EINVAL;
2147
2148 out_invalid_fh:
2149 dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2150 return -EINVAL;
2151 }
2152
2153 #if IS_ENABLED(CONFIG_NFS_V4)
nfs_validate_mount_data(struct file_system_type * fs_type,void * options,struct nfs_parsed_mount_data * args,struct nfs_fh * mntfh,const char * dev_name)2154 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2155 void *options,
2156 struct nfs_parsed_mount_data *args,
2157 struct nfs_fh *mntfh,
2158 const char *dev_name)
2159 {
2160 if (fs_type == &nfs_fs_type)
2161 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2162 return nfs4_validate_mount_data(options, args, dev_name);
2163 }
2164 #else
nfs_validate_mount_data(struct file_system_type * fs_type,void * options,struct nfs_parsed_mount_data * args,struct nfs_fh * mntfh,const char * dev_name)2165 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2166 void *options,
2167 struct nfs_parsed_mount_data *args,
2168 struct nfs_fh *mntfh,
2169 const char *dev_name)
2170 {
2171 return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2172 }
2173 #endif
2174
nfs_validate_text_mount_data(void * options,struct nfs_parsed_mount_data * args,const char * dev_name)2175 static int nfs_validate_text_mount_data(void *options,
2176 struct nfs_parsed_mount_data *args,
2177 const char *dev_name)
2178 {
2179 int port = 0;
2180 int max_namelen = PAGE_SIZE;
2181 int max_pathlen = NFS_MAXPATHLEN;
2182 struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2183
2184 if (nfs_parse_mount_options((char *)options, args) == 0)
2185 return -EINVAL;
2186
2187 if (!nfs_verify_server_address(sap))
2188 goto out_no_address;
2189
2190 if (args->version == 4) {
2191 #if IS_ENABLED(CONFIG_NFS_V4)
2192 if (args->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
2193 port = NFS_RDMA_PORT;
2194 else
2195 port = NFS_PORT;
2196 max_namelen = NFS4_MAXNAMLEN;
2197 max_pathlen = NFS4_MAXPATHLEN;
2198 nfs_validate_transport_protocol(args);
2199 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2200 goto out_invalid_transport_udp;
2201 nfs4_validate_mount_flags(args);
2202 #else
2203 goto out_v4_not_compiled;
2204 #endif /* CONFIG_NFS_V4 */
2205 } else {
2206 nfs_set_mount_transport_protocol(args);
2207 if (args->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
2208 port = NFS_RDMA_PORT;
2209 }
2210
2211 nfs_set_port(sap, &args->nfs_server.port, port);
2212
2213 return nfs_parse_devname(dev_name,
2214 &args->nfs_server.hostname,
2215 max_namelen,
2216 &args->nfs_server.export_path,
2217 max_pathlen);
2218
2219 #if !IS_ENABLED(CONFIG_NFS_V4)
2220 out_v4_not_compiled:
2221 dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2222 return -EPROTONOSUPPORT;
2223 #else
2224 out_invalid_transport_udp:
2225 dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2226 return -EINVAL;
2227 #endif /* !CONFIG_NFS_V4 */
2228
2229 out_no_address:
2230 dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2231 return -EINVAL;
2232 }
2233
2234 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \
2235 | NFS_MOUNT_SECURE \
2236 | NFS_MOUNT_TCP \
2237 | NFS_MOUNT_VER3 \
2238 | NFS_MOUNT_KERBEROS \
2239 | NFS_MOUNT_NONLM \
2240 | NFS_MOUNT_BROKEN_SUID \
2241 | NFS_MOUNT_STRICTLOCK \
2242 | NFS_MOUNT_LEGACY_INTERFACE)
2243
2244 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \
2245 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT))
2246
2247 static int
nfs_compare_remount_data(struct nfs_server * nfss,struct nfs_parsed_mount_data * data)2248 nfs_compare_remount_data(struct nfs_server *nfss,
2249 struct nfs_parsed_mount_data *data)
2250 {
2251 if ((data->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK ||
2252 data->rsize != nfss->rsize ||
2253 data->wsize != nfss->wsize ||
2254 data->version != nfss->nfs_client->rpc_ops->version ||
2255 data->minorversion != nfss->nfs_client->cl_minorversion ||
2256 data->retrans != nfss->client->cl_timeout->to_retries ||
2257 !nfs_auth_info_match(&data->auth_info, nfss->client->cl_auth->au_flavor) ||
2258 data->acregmin != nfss->acregmin / HZ ||
2259 data->acregmax != nfss->acregmax / HZ ||
2260 data->acdirmin != nfss->acdirmin / HZ ||
2261 data->acdirmax != nfss->acdirmax / HZ ||
2262 data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2263 (data->options & NFS_OPTION_FSCACHE) != (nfss->options & NFS_OPTION_FSCACHE) ||
2264 data->nfs_server.port != nfss->port ||
2265 data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2266 !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2267 (struct sockaddr *)&nfss->nfs_client->cl_addr))
2268 return -EINVAL;
2269
2270 return 0;
2271 }
2272
2273 int
nfs_remount(struct super_block * sb,int * flags,char * raw_data)2274 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2275 {
2276 int error;
2277 struct nfs_server *nfss = sb->s_fs_info;
2278 struct nfs_parsed_mount_data *data;
2279 struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2280 struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2281 u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2282
2283 sync_filesystem(sb);
2284
2285 /*
2286 * Userspace mount programs that send binary options generally send
2287 * them populated with default values. We have no way to know which
2288 * ones were explicitly specified. Fall back to legacy behavior and
2289 * just return success.
2290 */
2291 if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2292 (nfsvers <= 3 && (!options || (options->version >= 1 &&
2293 options->version <= 6))))
2294 return 0;
2295
2296 data = nfs_alloc_parsed_mount_data();
2297 if (data == NULL)
2298 return -ENOMEM;
2299
2300 /* fill out struct with values from existing mount */
2301 data->flags = nfss->flags;
2302 data->rsize = nfss->rsize;
2303 data->wsize = nfss->wsize;
2304 data->retrans = nfss->client->cl_timeout->to_retries;
2305 data->selected_flavor = nfss->client->cl_auth->au_flavor;
2306 data->acregmin = nfss->acregmin / HZ;
2307 data->acregmax = nfss->acregmax / HZ;
2308 data->acdirmin = nfss->acdirmin / HZ;
2309 data->acdirmax = nfss->acdirmax / HZ;
2310 data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2311 data->nfs_server.port = nfss->port;
2312 data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2313 data->version = nfsvers;
2314 data->minorversion = nfss->nfs_client->cl_minorversion;
2315 data->net = current->nsproxy->net_ns;
2316 memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2317 data->nfs_server.addrlen);
2318
2319 /* overwrite those values with any that were specified */
2320 error = -EINVAL;
2321 if (!nfs_parse_mount_options((char *)options, data))
2322 goto out;
2323
2324 /*
2325 * noac is a special case. It implies -o sync, but that's not
2326 * necessarily reflected in the mtab options. do_remount_sb
2327 * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the
2328 * remount options, so we have to explicitly reset it.
2329 */
2330 if (data->flags & NFS_MOUNT_NOAC)
2331 *flags |= SB_SYNCHRONOUS;
2332
2333 /* compare new mount options with old ones */
2334 error = nfs_compare_remount_data(nfss, data);
2335 if (!error)
2336 error = security_sb_remount(sb, data->lsm_opts);
2337 out:
2338 nfs_free_parsed_mount_data(data);
2339 return error;
2340 }
2341 EXPORT_SYMBOL_GPL(nfs_remount);
2342
2343 /*
2344 * Initialise the common bits of the superblock
2345 */
nfs_initialise_sb(struct super_block * sb)2346 static void nfs_initialise_sb(struct super_block *sb)
2347 {
2348 struct nfs_server *server = NFS_SB(sb);
2349
2350 sb->s_magic = NFS_SUPER_MAGIC;
2351
2352 /* We probably want something more informative here */
2353 snprintf(sb->s_id, sizeof(sb->s_id),
2354 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2355
2356 if (sb->s_blocksize == 0)
2357 sb->s_blocksize = nfs_block_bits(server->wsize,
2358 &sb->s_blocksize_bits);
2359
2360 nfs_super_set_maxbytes(sb, server->maxfilesize);
2361 }
2362
2363 /*
2364 * Finish setting up an NFS2/3 superblock
2365 */
nfs_fill_super(struct super_block * sb,struct nfs_mount_info * mount_info)2366 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2367 {
2368 struct nfs_parsed_mount_data *data = mount_info->parsed;
2369 struct nfs_server *server = NFS_SB(sb);
2370
2371 sb->s_blocksize_bits = 0;
2372 sb->s_blocksize = 0;
2373 sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2374 sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2375 if (data && data->bsize)
2376 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2377
2378 if (server->nfs_client->rpc_ops->version != 2) {
2379 /* The VFS shouldn't apply the umask to mode bits. We will do
2380 * so ourselves when necessary.
2381 */
2382 sb->s_flags |= SB_POSIXACL;
2383 sb->s_time_gran = 1;
2384 sb->s_export_op = &nfs_export_ops;
2385 } else
2386 sb->s_time_gran = 1000;
2387
2388 if (server->nfs_client->rpc_ops->version != 4) {
2389 sb->s_time_min = 0;
2390 sb->s_time_max = U32_MAX;
2391 } else {
2392 sb->s_time_min = S64_MIN;
2393 sb->s_time_max = S64_MAX;
2394 }
2395
2396 nfs_initialise_sb(sb);
2397 }
2398 EXPORT_SYMBOL_GPL(nfs_fill_super);
2399
2400 /*
2401 * Finish setting up a cloned NFS2/3/4 superblock
2402 */
nfs_clone_super(struct super_block * sb,struct nfs_mount_info * mount_info)2403 static void nfs_clone_super(struct super_block *sb,
2404 struct nfs_mount_info *mount_info)
2405 {
2406 const struct super_block *old_sb = mount_info->cloned->sb;
2407 struct nfs_server *server = NFS_SB(sb);
2408
2409 sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2410 sb->s_blocksize = old_sb->s_blocksize;
2411 sb->s_maxbytes = old_sb->s_maxbytes;
2412 sb->s_xattr = old_sb->s_xattr;
2413 sb->s_op = old_sb->s_op;
2414 sb->s_export_op = old_sb->s_export_op;
2415
2416 if (server->nfs_client->rpc_ops->version != 2) {
2417 /* The VFS shouldn't apply the umask to mode bits. We will do
2418 * so ourselves when necessary.
2419 */
2420 sb->s_flags |= SB_POSIXACL;
2421 sb->s_time_gran = 1;
2422 } else
2423 sb->s_time_gran = 1000;
2424
2425 if (server->nfs_client->rpc_ops->version != 4) {
2426 sb->s_time_min = 0;
2427 sb->s_time_max = U32_MAX;
2428 } else {
2429 sb->s_time_min = S64_MIN;
2430 sb->s_time_max = S64_MAX;
2431 }
2432
2433 nfs_initialise_sb(sb);
2434 }
2435
nfs_compare_mount_options(const struct super_block * s,const struct nfs_server * b,int flags)2436 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2437 {
2438 const struct nfs_server *a = s->s_fs_info;
2439 const struct rpc_clnt *clnt_a = a->client;
2440 const struct rpc_clnt *clnt_b = b->client;
2441
2442 if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2443 goto Ebusy;
2444 if (a->nfs_client != b->nfs_client)
2445 goto Ebusy;
2446 if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK)
2447 goto Ebusy;
2448 if (a->wsize != b->wsize)
2449 goto Ebusy;
2450 if (a->rsize != b->rsize)
2451 goto Ebusy;
2452 if (a->acregmin != b->acregmin)
2453 goto Ebusy;
2454 if (a->acregmax != b->acregmax)
2455 goto Ebusy;
2456 if (a->acdirmin != b->acdirmin)
2457 goto Ebusy;
2458 if (a->acdirmax != b->acdirmax)
2459 goto Ebusy;
2460 if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2461 goto Ebusy;
2462 return 1;
2463 Ebusy:
2464 return 0;
2465 }
2466
2467 struct nfs_sb_mountdata {
2468 struct nfs_server *server;
2469 int mntflags;
2470 };
2471
nfs_set_super(struct super_block * s,void * data)2472 static int nfs_set_super(struct super_block *s, void *data)
2473 {
2474 struct nfs_sb_mountdata *sb_mntdata = data;
2475 struct nfs_server *server = sb_mntdata->server;
2476 int ret;
2477
2478 s->s_flags = sb_mntdata->mntflags;
2479 s->s_fs_info = server;
2480 s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2481 ret = set_anon_super(s, server);
2482 if (ret == 0)
2483 server->s_dev = s->s_dev;
2484 return ret;
2485 }
2486
nfs_compare_super_address(struct nfs_server * server1,struct nfs_server * server2)2487 static int nfs_compare_super_address(struct nfs_server *server1,
2488 struct nfs_server *server2)
2489 {
2490 struct sockaddr *sap1, *sap2;
2491 struct rpc_xprt *xprt1 = server1->client->cl_xprt;
2492 struct rpc_xprt *xprt2 = server2->client->cl_xprt;
2493
2494 if (!net_eq(xprt1->xprt_net, xprt2->xprt_net))
2495 return 0;
2496
2497 sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2498 sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2499
2500 if (sap1->sa_family != sap2->sa_family)
2501 return 0;
2502
2503 switch (sap1->sa_family) {
2504 case AF_INET: {
2505 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2506 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2507 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2508 return 0;
2509 if (sin1->sin_port != sin2->sin_port)
2510 return 0;
2511 break;
2512 }
2513 case AF_INET6: {
2514 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2515 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2516 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2517 return 0;
2518 if (sin1->sin6_port != sin2->sin6_port)
2519 return 0;
2520 break;
2521 }
2522 default:
2523 return 0;
2524 }
2525
2526 return 1;
2527 }
2528
nfs_compare_userns(const struct nfs_server * old,const struct nfs_server * new)2529 static int nfs_compare_userns(const struct nfs_server *old,
2530 const struct nfs_server *new)
2531 {
2532 const struct user_namespace *oldns = &init_user_ns;
2533 const struct user_namespace *newns = &init_user_ns;
2534
2535 if (old->client && old->client->cl_cred)
2536 oldns = old->client->cl_cred->user_ns;
2537 if (new->client && new->client->cl_cred)
2538 newns = new->client->cl_cred->user_ns;
2539 if (oldns != newns)
2540 return 0;
2541 return 1;
2542 }
2543
nfs_compare_super(struct super_block * sb,void * data)2544 static int nfs_compare_super(struct super_block *sb, void *data)
2545 {
2546 struct nfs_sb_mountdata *sb_mntdata = data;
2547 struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2548 int mntflags = sb_mntdata->mntflags;
2549
2550 if (!nfs_compare_super_address(old, server))
2551 return 0;
2552 /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2553 if (old->flags & NFS_MOUNT_UNSHARED)
2554 return 0;
2555 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2556 return 0;
2557 if (!nfs_compare_userns(old, server))
2558 return 0;
2559 return nfs_compare_mount_options(sb, server, mntflags);
2560 }
2561
2562 #ifdef CONFIG_NFS_FSCACHE
nfs_get_cache_cookie(struct super_block * sb,struct nfs_parsed_mount_data * parsed,struct nfs_clone_mount * cloned)2563 static void nfs_get_cache_cookie(struct super_block *sb,
2564 struct nfs_parsed_mount_data *parsed,
2565 struct nfs_clone_mount *cloned)
2566 {
2567 struct nfs_server *nfss = NFS_SB(sb);
2568 char *uniq = NULL;
2569 int ulen = 0;
2570
2571 nfss->fscache_key = NULL;
2572 nfss->fscache = NULL;
2573
2574 if (parsed) {
2575 if (!(parsed->options & NFS_OPTION_FSCACHE))
2576 return;
2577 if (parsed->fscache_uniq) {
2578 uniq = parsed->fscache_uniq;
2579 ulen = strlen(parsed->fscache_uniq);
2580 }
2581 } else if (cloned) {
2582 struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2583 if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2584 return;
2585 if (mnt_s->fscache_key) {
2586 uniq = mnt_s->fscache_key->key.uniquifier;
2587 ulen = mnt_s->fscache_key->key.uniq_len;
2588 };
2589 } else
2590 return;
2591
2592 nfs_fscache_get_super_cookie(sb, uniq, ulen);
2593 }
2594 #else
nfs_get_cache_cookie(struct super_block * sb,struct nfs_parsed_mount_data * parsed,struct nfs_clone_mount * cloned)2595 static void nfs_get_cache_cookie(struct super_block *sb,
2596 struct nfs_parsed_mount_data *parsed,
2597 struct nfs_clone_mount *cloned)
2598 {
2599 }
2600 #endif
2601
nfs_set_sb_security(struct super_block * s,struct dentry * mntroot,struct nfs_mount_info * mount_info)2602 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2603 struct nfs_mount_info *mount_info)
2604 {
2605 int error;
2606 unsigned long kflags = 0, kflags_out = 0;
2607 if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2608 kflags |= SECURITY_LSM_NATIVE_LABELS;
2609
2610 error = security_sb_set_mnt_opts(s, mount_info->parsed->lsm_opts,
2611 kflags, &kflags_out);
2612 if (error)
2613 goto err;
2614
2615 if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2616 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2617 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2618 err:
2619 return error;
2620 }
2621 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2622
nfs_clone_sb_security(struct super_block * s,struct dentry * mntroot,struct nfs_mount_info * mount_info)2623 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2624 struct nfs_mount_info *mount_info)
2625 {
2626 int error;
2627 unsigned long kflags = 0, kflags_out = 0;
2628
2629 /* clone any lsm security options from the parent to the new sb */
2630 if (d_inode(mntroot)->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2631 return -ESTALE;
2632
2633 if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2634 kflags |= SECURITY_LSM_NATIVE_LABELS;
2635
2636 error = security_sb_clone_mnt_opts(mount_info->cloned->sb, s, kflags,
2637 &kflags_out);
2638 if (error)
2639 return error;
2640
2641 if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2642 !(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2643 NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2644 return 0;
2645 }
2646 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2647
nfs_set_readahead(struct backing_dev_info * bdi,unsigned long iomax_pages)2648 static void nfs_set_readahead(struct backing_dev_info *bdi,
2649 unsigned long iomax_pages)
2650 {
2651 bdi->ra_pages = VM_READAHEAD_PAGES;
2652 bdi->io_pages = iomax_pages;
2653 }
2654
nfs_fs_mount_common(struct nfs_server * server,int flags,const char * dev_name,struct nfs_mount_info * mount_info,struct nfs_subversion * nfs_mod)2655 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2656 int flags, const char *dev_name,
2657 struct nfs_mount_info *mount_info,
2658 struct nfs_subversion *nfs_mod)
2659 {
2660 struct super_block *s;
2661 struct dentry *mntroot = ERR_PTR(-ENOMEM);
2662 int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2663 struct nfs_sb_mountdata sb_mntdata = {
2664 .mntflags = flags,
2665 .server = server,
2666 };
2667 int error;
2668
2669 if (server->flags & NFS_MOUNT_UNSHARED)
2670 compare_super = NULL;
2671
2672 /* -o noac implies -o sync */
2673 if (server->flags & NFS_MOUNT_NOAC)
2674 sb_mntdata.mntflags |= SB_SYNCHRONOUS;
2675
2676 if (mount_info->cloned != NULL && mount_info->cloned->sb != NULL)
2677 if (mount_info->cloned->sb->s_flags & SB_SYNCHRONOUS)
2678 sb_mntdata.mntflags |= SB_SYNCHRONOUS;
2679
2680 /* Get a superblock - note that we may end up sharing one that already exists */
2681 s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2682 if (IS_ERR(s)) {
2683 mntroot = ERR_CAST(s);
2684 goto out_err_nosb;
2685 }
2686
2687 if (s->s_fs_info != server) {
2688 nfs_free_server(server);
2689 server = NULL;
2690 } else {
2691 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev),
2692 MINOR(server->s_dev));
2693 if (error) {
2694 mntroot = ERR_PTR(error);
2695 goto error_splat_super;
2696 }
2697 nfs_set_readahead(s->s_bdi, server->rpages);
2698 server->super = s;
2699 }
2700
2701 if (!s->s_root) {
2702 /* initial superblock/root creation */
2703 mount_info->fill_super(s, mount_info);
2704 nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2705 if (!(server->flags & NFS_MOUNT_UNSHARED))
2706 s->s_iflags |= SB_I_MULTIROOT;
2707 }
2708
2709 mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2710 if (IS_ERR(mntroot))
2711 goto error_splat_super;
2712
2713 error = mount_info->set_security(s, mntroot, mount_info);
2714 if (error)
2715 goto error_splat_root;
2716
2717 s->s_flags |= SB_ACTIVE;
2718
2719 out:
2720 return mntroot;
2721
2722 out_err_nosb:
2723 nfs_free_server(server);
2724 goto out;
2725
2726 error_splat_root:
2727 dput(mntroot);
2728 mntroot = ERR_PTR(error);
2729 error_splat_super:
2730 deactivate_locked_super(s);
2731 goto out;
2732 }
2733 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2734
nfs_fs_mount(struct file_system_type * fs_type,int flags,const char * dev_name,void * raw_data)2735 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2736 int flags, const char *dev_name, void *raw_data)
2737 {
2738 struct nfs_mount_info mount_info = {
2739 .fill_super = nfs_fill_super,
2740 .set_security = nfs_set_sb_security,
2741 };
2742 struct dentry *mntroot = ERR_PTR(-ENOMEM);
2743 struct nfs_subversion *nfs_mod;
2744 int error;
2745
2746 mount_info.parsed = nfs_alloc_parsed_mount_data();
2747 mount_info.mntfh = nfs_alloc_fhandle();
2748 if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2749 goto out;
2750
2751 /* Validate the mount data */
2752 error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2753 if (error == NFS_TEXT_DATA)
2754 error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2755 if (error < 0) {
2756 mntroot = ERR_PTR(error);
2757 goto out;
2758 }
2759
2760 nfs_mod = get_nfs_version(mount_info.parsed->version);
2761 if (IS_ERR(nfs_mod)) {
2762 mntroot = ERR_CAST(nfs_mod);
2763 goto out;
2764 }
2765
2766 mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2767
2768 put_nfs_version(nfs_mod);
2769 out:
2770 nfs_free_parsed_mount_data(mount_info.parsed);
2771 nfs_free_fhandle(mount_info.mntfh);
2772 return mntroot;
2773 }
2774 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2775
2776 /*
2777 * Destroy an NFS2/3 superblock
2778 */
nfs_kill_super(struct super_block * s)2779 void nfs_kill_super(struct super_block *s)
2780 {
2781 struct nfs_server *server = NFS_SB(s);
2782 dev_t dev = s->s_dev;
2783
2784 generic_shutdown_super(s);
2785
2786 nfs_fscache_release_super_cookie(s);
2787
2788 nfs_free_server(server);
2789 free_anon_bdev(dev);
2790 }
2791 EXPORT_SYMBOL_GPL(nfs_kill_super);
2792
2793 /*
2794 * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2795 */
2796 static struct dentry *
nfs_xdev_mount(struct file_system_type * fs_type,int flags,const char * dev_name,void * raw_data)2797 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2798 const char *dev_name, void *raw_data)
2799 {
2800 struct nfs_clone_mount *data = raw_data;
2801 struct nfs_mount_info mount_info = {
2802 .fill_super = nfs_clone_super,
2803 .set_security = nfs_clone_sb_security,
2804 .cloned = data,
2805 };
2806 struct nfs_server *server;
2807 struct dentry *mntroot = ERR_PTR(-ENOMEM);
2808 struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2809
2810 dprintk("--> nfs_xdev_mount()\n");
2811
2812 mount_info.mntfh = mount_info.cloned->fh;
2813
2814 /* create a new volume representation */
2815 server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2816
2817 if (IS_ERR(server))
2818 mntroot = ERR_CAST(server);
2819 else
2820 mntroot = nfs_fs_mount_common(server, flags,
2821 dev_name, &mount_info, nfs_mod);
2822
2823 dprintk("<-- nfs_xdev_mount() = %ld\n",
2824 IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2825 return mntroot;
2826 }
2827
2828 #if IS_ENABLED(CONFIG_NFS_V4)
2829
nfs4_validate_mount_flags(struct nfs_parsed_mount_data * args)2830 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2831 {
2832 args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2833 NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2834 }
2835
2836 /*
2837 * Validate NFSv4 mount options
2838 */
nfs4_validate_mount_data(void * options,struct nfs_parsed_mount_data * args,const char * dev_name)2839 static int nfs4_validate_mount_data(void *options,
2840 struct nfs_parsed_mount_data *args,
2841 const char *dev_name)
2842 {
2843 struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2844 struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2845 char *c;
2846
2847 if (data == NULL)
2848 goto out_no_data;
2849
2850 args->version = 4;
2851
2852 switch (data->version) {
2853 case 1:
2854 if (data->host_addrlen > sizeof(args->nfs_server.address))
2855 goto out_no_address;
2856 if (data->host_addrlen == 0)
2857 goto out_no_address;
2858 args->nfs_server.addrlen = data->host_addrlen;
2859 if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2860 return -EFAULT;
2861 if (!nfs_verify_server_address(sap))
2862 goto out_no_address;
2863 args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2864
2865 if (data->auth_flavourlen) {
2866 rpc_authflavor_t pseudoflavor;
2867 if (data->auth_flavourlen > 1)
2868 goto out_inval_auth;
2869 if (copy_from_user(&pseudoflavor,
2870 data->auth_flavours,
2871 sizeof(pseudoflavor)))
2872 return -EFAULT;
2873 args->selected_flavor = pseudoflavor;
2874 } else
2875 args->selected_flavor = RPC_AUTH_UNIX;
2876
2877 c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2878 if (IS_ERR(c))
2879 return PTR_ERR(c);
2880 args->nfs_server.hostname = c;
2881
2882 c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2883 if (IS_ERR(c))
2884 return PTR_ERR(c);
2885 args->nfs_server.export_path = c;
2886 dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2887
2888 c = strndup_user(data->client_addr.data, 16);
2889 if (IS_ERR(c))
2890 return PTR_ERR(c);
2891 args->client_address = c;
2892
2893 /*
2894 * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2895 * can deal with.
2896 */
2897
2898 args->flags = data->flags & NFS4_MOUNT_FLAGMASK;
2899 args->rsize = data->rsize;
2900 args->wsize = data->wsize;
2901 args->timeo = data->timeo;
2902 args->retrans = data->retrans;
2903 args->acregmin = data->acregmin;
2904 args->acregmax = data->acregmax;
2905 args->acdirmin = data->acdirmin;
2906 args->acdirmax = data->acdirmax;
2907 args->nfs_server.protocol = data->proto;
2908 nfs_validate_transport_protocol(args);
2909 if (args->nfs_server.protocol == XPRT_TRANSPORT_UDP)
2910 goto out_invalid_transport_udp;
2911
2912 break;
2913 default:
2914 return NFS_TEXT_DATA;
2915 }
2916
2917 return 0;
2918
2919 out_no_data:
2920 dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2921 return -EINVAL;
2922
2923 out_inval_auth:
2924 dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2925 data->auth_flavourlen);
2926 return -EINVAL;
2927
2928 out_no_address:
2929 dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2930 return -EINVAL;
2931
2932 out_invalid_transport_udp:
2933 dfprintk(MOUNT, "NFSv4: Unsupported transport protocol udp\n");
2934 return -EINVAL;
2935 }
2936
2937 /*
2938 * NFS v4 module parameters need to stay in the
2939 * NFS client for backwards compatibility
2940 */
2941 unsigned int nfs_callback_set_tcpport;
2942 unsigned short nfs_callback_nr_threads;
2943 /* Default cache timeout is 10 minutes */
2944 unsigned int nfs_idmap_cache_timeout = 600;
2945 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2946 bool nfs4_disable_idmapping = true;
2947 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2948 unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE;
2949 unsigned short send_implementation_id = 1;
2950 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2951 bool recover_lost_locks = false;
2952
2953 EXPORT_SYMBOL_GPL(nfs_callback_nr_threads);
2954 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2955 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2956 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2957 EXPORT_SYMBOL_GPL(max_session_slots);
2958 EXPORT_SYMBOL_GPL(max_session_cb_slots);
2959 EXPORT_SYMBOL_GPL(send_implementation_id);
2960 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2961 EXPORT_SYMBOL_GPL(recover_lost_locks);
2962
2963 #define NFS_CALLBACK_MAXPORTNR (65535U)
2964
param_set_portnr(const char * val,const struct kernel_param * kp)2965 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2966 {
2967 unsigned long num;
2968 int ret;
2969
2970 if (!val)
2971 return -EINVAL;
2972 ret = kstrtoul(val, 0, &num);
2973 if (ret || num > NFS_CALLBACK_MAXPORTNR)
2974 return -EINVAL;
2975 *((unsigned int *)kp->arg) = num;
2976 return 0;
2977 }
2978 static const struct kernel_param_ops param_ops_portnr = {
2979 .set = param_set_portnr,
2980 .get = param_get_uint,
2981 };
2982 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2983
2984 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2985 module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644);
2986 MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be "
2987 "assigned to the NFSv4 callback channels.");
2988 module_param(nfs_idmap_cache_timeout, int, 0644);
2989 module_param(nfs4_disable_idmapping, bool, 0644);
2990 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2991 NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2992 MODULE_PARM_DESC(nfs4_disable_idmapping,
2993 "Turn off NFSv4 idmapping when using 'sec=sys'");
2994 module_param(max_session_slots, ushort, 0644);
2995 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2996 "requests the client will negotiate");
2997 module_param(max_session_cb_slots, ushort, 0644);
2998 MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 "
2999 "callbacks the client will process for a given server");
3000 module_param(send_implementation_id, ushort, 0644);
3001 MODULE_PARM_DESC(send_implementation_id,
3002 "Send implementation ID with NFSv4.1 exchange_id");
3003 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
3004
3005 module_param(recover_lost_locks, bool, 0644);
3006 MODULE_PARM_DESC(recover_lost_locks,
3007 "If the server reports that a lock might be lost, "
3008 "try to recover it risking data corruption.");
3009
3010
3011 #endif /* CONFIG_NFS_V4 */
3012
