xref: /openbmc/linux/fs/nfs/super.c (revision 5104d265)
1 /*
2  *  linux/fs/nfs/super.c
3  *
4  *  Copyright (C) 1992  Rick Sladkey
5  *
6  *  nfs superblock handling functions
7  *
8  *  Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some
9  *  experimental NFS changes. Modularisation taken straight from SYS5 fs.
10  *
11  *  Change to nfs_read_super() to permit NFS mounts to multi-homed hosts.
12  *  J.S.Peatfield@damtp.cam.ac.uk
13  *
14  *  Split from inode.c by David Howells <dhowells@redhat.com>
15  *
16  * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a
17  *   particular server are held in the same superblock
18  * - NFS superblocks can have several effective roots to the dentry tree
19  * - directory type roots are spliced into the tree when a path from one root reaches the root
20  *   of another (see nfs_lookup())
21  */
22 
23 #include <linux/module.h>
24 #include <linux/init.h>
25 
26 #include <linux/time.h>
27 #include <linux/kernel.h>
28 #include <linux/mm.h>
29 #include <linux/string.h>
30 #include <linux/stat.h>
31 #include <linux/errno.h>
32 #include <linux/unistd.h>
33 #include <linux/sunrpc/clnt.h>
34 #include <linux/sunrpc/addr.h>
35 #include <linux/sunrpc/stats.h>
36 #include <linux/sunrpc/metrics.h>
37 #include <linux/sunrpc/xprtsock.h>
38 #include <linux/sunrpc/xprtrdma.h>
39 #include <linux/nfs_fs.h>
40 #include <linux/nfs_mount.h>
41 #include <linux/nfs4_mount.h>
42 #include <linux/lockd/bind.h>
43 #include <linux/seq_file.h>
44 #include <linux/mount.h>
45 #include <linux/namei.h>
46 #include <linux/nfs_idmap.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 <asm/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 enum {
81 	/* Mount options that take no arguments */
82 	Opt_soft, Opt_hard,
83 	Opt_posix, Opt_noposix,
84 	Opt_cto, Opt_nocto,
85 	Opt_ac, Opt_noac,
86 	Opt_lock, Opt_nolock,
87 	Opt_udp, Opt_tcp, Opt_rdma,
88 	Opt_acl, Opt_noacl,
89 	Opt_rdirplus, Opt_nordirplus,
90 	Opt_sharecache, Opt_nosharecache,
91 	Opt_resvport, Opt_noresvport,
92 	Opt_fscache, Opt_nofscache,
93 	Opt_migration, Opt_nomigration,
94 
95 	/* Mount options that take integer arguments */
96 	Opt_port,
97 	Opt_rsize, Opt_wsize, Opt_bsize,
98 	Opt_timeo, Opt_retrans,
99 	Opt_acregmin, Opt_acregmax,
100 	Opt_acdirmin, Opt_acdirmax,
101 	Opt_actimeo,
102 	Opt_namelen,
103 	Opt_mountport,
104 	Opt_mountvers,
105 	Opt_minorversion,
106 
107 	/* Mount options that take string arguments */
108 	Opt_nfsvers,
109 	Opt_sec, Opt_proto, Opt_mountproto, Opt_mounthost,
110 	Opt_addr, Opt_mountaddr, Opt_clientaddr,
111 	Opt_lookupcache,
112 	Opt_fscache_uniq,
113 	Opt_local_lock,
114 
115 	/* Special mount options */
116 	Opt_userspace, Opt_deprecated, Opt_sloppy,
117 
118 	Opt_err
119 };
120 
121 static const match_table_t nfs_mount_option_tokens = {
122 	{ Opt_userspace, "bg" },
123 	{ Opt_userspace, "fg" },
124 	{ Opt_userspace, "retry=%s" },
125 
126 	{ Opt_sloppy, "sloppy" },
127 
128 	{ Opt_soft, "soft" },
129 	{ Opt_hard, "hard" },
130 	{ Opt_deprecated, "intr" },
131 	{ Opt_deprecated, "nointr" },
132 	{ Opt_posix, "posix" },
133 	{ Opt_noposix, "noposix" },
134 	{ Opt_cto, "cto" },
135 	{ Opt_nocto, "nocto" },
136 	{ Opt_ac, "ac" },
137 	{ Opt_noac, "noac" },
138 	{ Opt_lock, "lock" },
139 	{ Opt_nolock, "nolock" },
140 	{ Opt_udp, "udp" },
141 	{ Opt_tcp, "tcp" },
142 	{ Opt_rdma, "rdma" },
143 	{ Opt_acl, "acl" },
144 	{ Opt_noacl, "noacl" },
145 	{ Opt_rdirplus, "rdirplus" },
146 	{ Opt_nordirplus, "nordirplus" },
147 	{ Opt_sharecache, "sharecache" },
148 	{ Opt_nosharecache, "nosharecache" },
149 	{ Opt_resvport, "resvport" },
150 	{ Opt_noresvport, "noresvport" },
151 	{ Opt_fscache, "fsc" },
152 	{ Opt_nofscache, "nofsc" },
153 	{ Opt_migration, "migration" },
154 	{ Opt_nomigration, "nomigration" },
155 
156 	{ Opt_port, "port=%s" },
157 	{ Opt_rsize, "rsize=%s" },
158 	{ Opt_wsize, "wsize=%s" },
159 	{ Opt_bsize, "bsize=%s" },
160 	{ Opt_timeo, "timeo=%s" },
161 	{ Opt_retrans, "retrans=%s" },
162 	{ Opt_acregmin, "acregmin=%s" },
163 	{ Opt_acregmax, "acregmax=%s" },
164 	{ Opt_acdirmin, "acdirmin=%s" },
165 	{ Opt_acdirmax, "acdirmax=%s" },
166 	{ Opt_actimeo, "actimeo=%s" },
167 	{ Opt_namelen, "namlen=%s" },
168 	{ Opt_mountport, "mountport=%s" },
169 	{ Opt_mountvers, "mountvers=%s" },
170 	{ Opt_minorversion, "minorversion=%s" },
171 
172 	{ Opt_nfsvers, "nfsvers=%s" },
173 	{ Opt_nfsvers, "vers=%s" },
174 
175 	{ Opt_sec, "sec=%s" },
176 	{ Opt_proto, "proto=%s" },
177 	{ Opt_mountproto, "mountproto=%s" },
178 	{ Opt_addr, "addr=%s" },
179 	{ Opt_clientaddr, "clientaddr=%s" },
180 	{ Opt_mounthost, "mounthost=%s" },
181 	{ Opt_mountaddr, "mountaddr=%s" },
182 
183 	{ Opt_lookupcache, "lookupcache=%s" },
184 	{ Opt_fscache_uniq, "fsc=%s" },
185 	{ Opt_local_lock, "local_lock=%s" },
186 
187 	/* The following needs to be listed after all other options */
188 	{ Opt_nfsvers, "v%s" },
189 
190 	{ Opt_err, NULL }
191 };
192 
193 enum {
194 	Opt_xprt_udp, Opt_xprt_udp6, Opt_xprt_tcp, Opt_xprt_tcp6, Opt_xprt_rdma,
195 
196 	Opt_xprt_err
197 };
198 
199 static const match_table_t nfs_xprt_protocol_tokens = {
200 	{ Opt_xprt_udp, "udp" },
201 	{ Opt_xprt_udp6, "udp6" },
202 	{ Opt_xprt_tcp, "tcp" },
203 	{ Opt_xprt_tcp6, "tcp6" },
204 	{ Opt_xprt_rdma, "rdma" },
205 
206 	{ Opt_xprt_err, NULL }
207 };
208 
209 enum {
210 	Opt_sec_none, Opt_sec_sys,
211 	Opt_sec_krb5, Opt_sec_krb5i, Opt_sec_krb5p,
212 	Opt_sec_lkey, Opt_sec_lkeyi, Opt_sec_lkeyp,
213 	Opt_sec_spkm, Opt_sec_spkmi, Opt_sec_spkmp,
214 
215 	Opt_sec_err
216 };
217 
218 static const match_table_t nfs_secflavor_tokens = {
219 	{ Opt_sec_none, "none" },
220 	{ Opt_sec_none, "null" },
221 	{ Opt_sec_sys, "sys" },
222 
223 	{ Opt_sec_krb5, "krb5" },
224 	{ Opt_sec_krb5i, "krb5i" },
225 	{ Opt_sec_krb5p, "krb5p" },
226 
227 	{ Opt_sec_lkey, "lkey" },
228 	{ Opt_sec_lkeyi, "lkeyi" },
229 	{ Opt_sec_lkeyp, "lkeyp" },
230 
231 	{ Opt_sec_spkm, "spkm3" },
232 	{ Opt_sec_spkmi, "spkm3i" },
233 	{ Opt_sec_spkmp, "spkm3p" },
234 
235 	{ Opt_sec_err, NULL }
236 };
237 
238 enum {
239 	Opt_lookupcache_all, Opt_lookupcache_positive,
240 	Opt_lookupcache_none,
241 
242 	Opt_lookupcache_err
243 };
244 
245 static match_table_t nfs_lookupcache_tokens = {
246 	{ Opt_lookupcache_all, "all" },
247 	{ Opt_lookupcache_positive, "pos" },
248 	{ Opt_lookupcache_positive, "positive" },
249 	{ Opt_lookupcache_none, "none" },
250 
251 	{ Opt_lookupcache_err, NULL }
252 };
253 
254 enum {
255 	Opt_local_lock_all, Opt_local_lock_flock, Opt_local_lock_posix,
256 	Opt_local_lock_none,
257 
258 	Opt_local_lock_err
259 };
260 
261 static match_table_t nfs_local_lock_tokens = {
262 	{ Opt_local_lock_all, "all" },
263 	{ Opt_local_lock_flock, "flock" },
264 	{ Opt_local_lock_posix, "posix" },
265 	{ Opt_local_lock_none, "none" },
266 
267 	{ Opt_local_lock_err, NULL }
268 };
269 
270 enum {
271 	Opt_vers_2, Opt_vers_3, Opt_vers_4, Opt_vers_4_0,
272 	Opt_vers_4_1, Opt_vers_4_2,
273 
274 	Opt_vers_err
275 };
276 
277 static match_table_t nfs_vers_tokens = {
278 	{ Opt_vers_2, "2" },
279 	{ Opt_vers_3, "3" },
280 	{ Opt_vers_4, "4" },
281 	{ Opt_vers_4_0, "4.0" },
282 	{ Opt_vers_4_1, "4.1" },
283 	{ Opt_vers_4_2, "4.2" },
284 
285 	{ Opt_vers_err, NULL }
286 };
287 
288 static struct dentry *nfs_xdev_mount(struct file_system_type *fs_type,
289 		int flags, const char *dev_name, void *raw_data);
290 
291 struct file_system_type nfs_fs_type = {
292 	.owner		= THIS_MODULE,
293 	.name		= "nfs",
294 	.mount		= nfs_fs_mount,
295 	.kill_sb	= nfs_kill_super,
296 	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
297 };
298 MODULE_ALIAS_FS("nfs");
299 EXPORT_SYMBOL_GPL(nfs_fs_type);
300 
301 struct file_system_type nfs_xdev_fs_type = {
302 	.owner		= THIS_MODULE,
303 	.name		= "nfs",
304 	.mount		= nfs_xdev_mount,
305 	.kill_sb	= nfs_kill_super,
306 	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
307 };
308 
309 const struct super_operations nfs_sops = {
310 	.alloc_inode	= nfs_alloc_inode,
311 	.destroy_inode	= nfs_destroy_inode,
312 	.write_inode	= nfs_write_inode,
313 	.drop_inode	= nfs_drop_inode,
314 	.put_super	= nfs_put_super,
315 	.statfs		= nfs_statfs,
316 	.evict_inode	= nfs_evict_inode,
317 	.umount_begin	= nfs_umount_begin,
318 	.show_options	= nfs_show_options,
319 	.show_devname	= nfs_show_devname,
320 	.show_path	= nfs_show_path,
321 	.show_stats	= nfs_show_stats,
322 	.remount_fs	= nfs_remount,
323 };
324 EXPORT_SYMBOL_GPL(nfs_sops);
325 
326 #if IS_ENABLED(CONFIG_NFS_V4)
327 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
328 static int nfs4_validate_mount_data(void *options,
329 	struct nfs_parsed_mount_data *args, const char *dev_name);
330 
331 struct file_system_type nfs4_fs_type = {
332 	.owner		= THIS_MODULE,
333 	.name		= "nfs4",
334 	.mount		= nfs_fs_mount,
335 	.kill_sb	= nfs_kill_super,
336 	.fs_flags	= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
337 };
338 MODULE_ALIAS_FS("nfs4");
339 MODULE_ALIAS("nfs4");
340 EXPORT_SYMBOL_GPL(nfs4_fs_type);
341 
342 static int __init register_nfs4_fs(void)
343 {
344 	return register_filesystem(&nfs4_fs_type);
345 }
346 
347 static void unregister_nfs4_fs(void)
348 {
349 	unregister_filesystem(&nfs4_fs_type);
350 }
351 #else
352 static int __init register_nfs4_fs(void)
353 {
354 	return 0;
355 }
356 
357 static void unregister_nfs4_fs(void)
358 {
359 }
360 #endif
361 
362 static struct shrinker acl_shrinker = {
363 	.shrink		= nfs_access_cache_shrinker,
364 	.seeks		= DEFAULT_SEEKS,
365 };
366 
367 /*
368  * Register the NFS filesystems
369  */
370 int __init register_nfs_fs(void)
371 {
372 	int ret;
373 
374         ret = register_filesystem(&nfs_fs_type);
375 	if (ret < 0)
376 		goto error_0;
377 
378 	ret = register_nfs4_fs();
379 	if (ret < 0)
380 		goto error_1;
381 
382 	ret = nfs_register_sysctl();
383 	if (ret < 0)
384 		goto error_2;
385 	register_shrinker(&acl_shrinker);
386 	return 0;
387 
388 error_2:
389 	unregister_nfs4_fs();
390 error_1:
391 	unregister_filesystem(&nfs_fs_type);
392 error_0:
393 	return ret;
394 }
395 
396 /*
397  * Unregister the NFS filesystems
398  */
399 void __exit unregister_nfs_fs(void)
400 {
401 	unregister_shrinker(&acl_shrinker);
402 	nfs_unregister_sysctl();
403 	unregister_nfs4_fs();
404 	unregister_filesystem(&nfs_fs_type);
405 }
406 
407 void nfs_sb_active(struct super_block *sb)
408 {
409 	struct nfs_server *server = NFS_SB(sb);
410 
411 	if (atomic_inc_return(&server->active) == 1)
412 		atomic_inc(&sb->s_active);
413 }
414 EXPORT_SYMBOL_GPL(nfs_sb_active);
415 
416 void nfs_sb_deactive(struct super_block *sb)
417 {
418 	struct nfs_server *server = NFS_SB(sb);
419 
420 	if (atomic_dec_and_test(&server->active))
421 		deactivate_super(sb);
422 }
423 EXPORT_SYMBOL_GPL(nfs_sb_deactive);
424 
425 /*
426  * Deliver file system statistics to userspace
427  */
428 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
429 {
430 	struct nfs_server *server = NFS_SB(dentry->d_sb);
431 	unsigned char blockbits;
432 	unsigned long blockres;
433 	struct nfs_fh *fh = NFS_FH(dentry->d_inode);
434 	struct nfs_fsstat res;
435 	int error = -ENOMEM;
436 
437 	res.fattr = nfs_alloc_fattr();
438 	if (res.fattr == NULL)
439 		goto out_err;
440 
441 	error = server->nfs_client->rpc_ops->statfs(server, fh, &res);
442 	if (unlikely(error == -ESTALE)) {
443 		struct dentry *pd_dentry;
444 
445 		pd_dentry = dget_parent(dentry);
446 		if (pd_dentry != NULL) {
447 			nfs_zap_caches(pd_dentry->d_inode);
448 			dput(pd_dentry);
449 		}
450 	}
451 	nfs_free_fattr(res.fattr);
452 	if (error < 0)
453 		goto out_err;
454 
455 	buf->f_type = NFS_SUPER_MAGIC;
456 
457 	/*
458 	 * Current versions of glibc do not correctly handle the
459 	 * case where f_frsize != f_bsize.  Eventually we want to
460 	 * report the value of wtmult in this field.
461 	 */
462 	buf->f_frsize = dentry->d_sb->s_blocksize;
463 
464 	/*
465 	 * On most *nix systems, f_blocks, f_bfree, and f_bavail
466 	 * are reported in units of f_frsize.  Linux hasn't had
467 	 * an f_frsize field in its statfs struct until recently,
468 	 * thus historically Linux's sys_statfs reports these
469 	 * fields in units of f_bsize.
470 	 */
471 	buf->f_bsize = dentry->d_sb->s_blocksize;
472 	blockbits = dentry->d_sb->s_blocksize_bits;
473 	blockres = (1 << blockbits) - 1;
474 	buf->f_blocks = (res.tbytes + blockres) >> blockbits;
475 	buf->f_bfree = (res.fbytes + blockres) >> blockbits;
476 	buf->f_bavail = (res.abytes + blockres) >> blockbits;
477 
478 	buf->f_files = res.tfiles;
479 	buf->f_ffree = res.afiles;
480 
481 	buf->f_namelen = server->namelen;
482 
483 	return 0;
484 
485  out_err:
486 	dprintk("%s: statfs error = %d\n", __func__, -error);
487 	return error;
488 }
489 EXPORT_SYMBOL_GPL(nfs_statfs);
490 
491 /*
492  * Map the security flavour number to a name
493  */
494 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour)
495 {
496 	static const struct {
497 		rpc_authflavor_t flavour;
498 		const char *str;
499 	} sec_flavours[] = {
500 		{ RPC_AUTH_NULL, "null" },
501 		{ RPC_AUTH_UNIX, "sys" },
502 		{ RPC_AUTH_GSS_KRB5, "krb5" },
503 		{ RPC_AUTH_GSS_KRB5I, "krb5i" },
504 		{ RPC_AUTH_GSS_KRB5P, "krb5p" },
505 		{ RPC_AUTH_GSS_LKEY, "lkey" },
506 		{ RPC_AUTH_GSS_LKEYI, "lkeyi" },
507 		{ RPC_AUTH_GSS_LKEYP, "lkeyp" },
508 		{ RPC_AUTH_GSS_SPKM, "spkm" },
509 		{ RPC_AUTH_GSS_SPKMI, "spkmi" },
510 		{ RPC_AUTH_GSS_SPKMP, "spkmp" },
511 		{ UINT_MAX, "unknown" }
512 	};
513 	int i;
514 
515 	for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) {
516 		if (sec_flavours[i].flavour == flavour)
517 			break;
518 	}
519 	return sec_flavours[i].str;
520 }
521 
522 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss,
523 				  int showdefaults)
524 {
525 	struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address;
526 
527 	seq_printf(m, ",mountproto=");
528 	switch (sap->sa_family) {
529 	case AF_INET:
530 		switch (nfss->mountd_protocol) {
531 		case IPPROTO_UDP:
532 			seq_printf(m, RPCBIND_NETID_UDP);
533 			break;
534 		case IPPROTO_TCP:
535 			seq_printf(m, RPCBIND_NETID_TCP);
536 			break;
537 		default:
538 			if (showdefaults)
539 				seq_printf(m, "auto");
540 		}
541 		break;
542 	case AF_INET6:
543 		switch (nfss->mountd_protocol) {
544 		case IPPROTO_UDP:
545 			seq_printf(m, RPCBIND_NETID_UDP6);
546 			break;
547 		case IPPROTO_TCP:
548 			seq_printf(m, RPCBIND_NETID_TCP6);
549 			break;
550 		default:
551 			if (showdefaults)
552 				seq_printf(m, "auto");
553 		}
554 		break;
555 	default:
556 		if (showdefaults)
557 			seq_printf(m, "auto");
558 	}
559 }
560 
561 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
562 				    int showdefaults)
563 {
564 	struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address;
565 
566 	if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE)
567 		return;
568 
569 	switch (sap->sa_family) {
570 	case AF_INET: {
571 		struct sockaddr_in *sin = (struct sockaddr_in *)sap;
572 		seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr);
573 		break;
574 	}
575 	case AF_INET6: {
576 		struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
577 		seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr);
578 		break;
579 	}
580 	default:
581 		if (showdefaults)
582 			seq_printf(m, ",mountaddr=unspecified");
583 	}
584 
585 	if (nfss->mountd_version || showdefaults)
586 		seq_printf(m, ",mountvers=%u", nfss->mountd_version);
587 	if ((nfss->mountd_port &&
588 		nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) ||
589 		showdefaults)
590 		seq_printf(m, ",mountport=%u", nfss->mountd_port);
591 
592 	nfs_show_mountd_netid(m, nfss, showdefaults);
593 }
594 
595 #if IS_ENABLED(CONFIG_NFS_V4)
596 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
597 				    int showdefaults)
598 {
599 	struct nfs_client *clp = nfss->nfs_client;
600 
601 	seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr);
602 }
603 #else
604 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
605 				    int showdefaults)
606 {
607 }
608 #endif
609 
610 static void nfs_show_nfs_version(struct seq_file *m,
611 		unsigned int version,
612 		unsigned int minorversion)
613 {
614 	seq_printf(m, ",vers=%u", version);
615 	if (version == 4)
616 		seq_printf(m, ".%u", minorversion);
617 }
618 
619 /*
620  * Describe the mount options in force on this server representation
621  */
622 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss,
623 				   int showdefaults)
624 {
625 	static const struct proc_nfs_info {
626 		int flag;
627 		const char *str;
628 		const char *nostr;
629 	} nfs_info[] = {
630 		{ NFS_MOUNT_SOFT, ",soft", ",hard" },
631 		{ NFS_MOUNT_POSIX, ",posix", "" },
632 		{ NFS_MOUNT_NOCTO, ",nocto", "" },
633 		{ NFS_MOUNT_NOAC, ",noac", "" },
634 		{ NFS_MOUNT_NONLM, ",nolock", "" },
635 		{ NFS_MOUNT_NOACL, ",noacl", "" },
636 		{ NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
637 		{ NFS_MOUNT_UNSHARED, ",nosharecache", "" },
638 		{ NFS_MOUNT_NORESVPORT, ",noresvport", "" },
639 		{ 0, NULL, NULL }
640 	};
641 	const struct proc_nfs_info *nfs_infop;
642 	struct nfs_client *clp = nfss->nfs_client;
643 	u32 version = clp->rpc_ops->version;
644 	int local_flock, local_fcntl;
645 
646 	nfs_show_nfs_version(m, version, clp->cl_minorversion);
647 	seq_printf(m, ",rsize=%u", nfss->rsize);
648 	seq_printf(m, ",wsize=%u", nfss->wsize);
649 	if (nfss->bsize != 0)
650 		seq_printf(m, ",bsize=%u", nfss->bsize);
651 	seq_printf(m, ",namlen=%u", nfss->namelen);
652 	if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults)
653 		seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ);
654 	if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults)
655 		seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ);
656 	if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults)
657 		seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ);
658 	if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults)
659 		seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ);
660 	for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) {
661 		if (nfss->flags & nfs_infop->flag)
662 			seq_puts(m, nfs_infop->str);
663 		else
664 			seq_puts(m, nfs_infop->nostr);
665 	}
666 	rcu_read_lock();
667 	seq_printf(m, ",proto=%s",
668 		   rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID));
669 	rcu_read_unlock();
670 	if (version == 4) {
671 		if (nfss->port != NFS_PORT)
672 			seq_printf(m, ",port=%u", nfss->port);
673 	} else
674 		if (nfss->port)
675 			seq_printf(m, ",port=%u", nfss->port);
676 
677 	seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ);
678 	seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries);
679 	seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor));
680 
681 	if (version != 4)
682 		nfs_show_mountd_options(m, nfss, showdefaults);
683 	else
684 		nfs_show_nfsv4_options(m, nfss, showdefaults);
685 
686 	if (nfss->options & NFS_OPTION_FSCACHE)
687 		seq_printf(m, ",fsc");
688 
689 	if (nfss->options & NFS_OPTION_MIGRATION)
690 		seq_printf(m, ",migration");
691 
692 	if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) {
693 		if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
694 			seq_printf(m, ",lookupcache=none");
695 		else
696 			seq_printf(m, ",lookupcache=pos");
697 	}
698 
699 	local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK;
700 	local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL;
701 
702 	if (!local_flock && !local_fcntl)
703 		seq_printf(m, ",local_lock=none");
704 	else if (local_flock && local_fcntl)
705 		seq_printf(m, ",local_lock=all");
706 	else if (local_flock)
707 		seq_printf(m, ",local_lock=flock");
708 	else
709 		seq_printf(m, ",local_lock=posix");
710 }
711 
712 /*
713  * Describe the mount options on this VFS mountpoint
714  */
715 int nfs_show_options(struct seq_file *m, struct dentry *root)
716 {
717 	struct nfs_server *nfss = NFS_SB(root->d_sb);
718 
719 	nfs_show_mount_options(m, nfss, 0);
720 
721 	rcu_read_lock();
722 	seq_printf(m, ",addr=%s",
723 			rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient,
724 							RPC_DISPLAY_ADDR));
725 	rcu_read_unlock();
726 
727 	return 0;
728 }
729 EXPORT_SYMBOL_GPL(nfs_show_options);
730 
731 #if IS_ENABLED(CONFIG_NFS_V4)
732 #ifdef CONFIG_NFS_V4_1
733 static void show_sessions(struct seq_file *m, struct nfs_server *server)
734 {
735 	if (nfs4_has_session(server->nfs_client))
736 		seq_printf(m, ",sessions");
737 }
738 #else
739 static void show_sessions(struct seq_file *m, struct nfs_server *server) {}
740 #endif
741 #endif
742 
743 #ifdef CONFIG_NFS_V4_1
744 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
745 {
746 	seq_printf(m, ",pnfs=");
747 	if (server->pnfs_curr_ld)
748 		seq_printf(m, "%s", server->pnfs_curr_ld->name);
749 	else
750 		seq_printf(m, "not configured");
751 }
752 
753 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
754 {
755 	if (nfss->nfs_client && nfss->nfs_client->cl_implid) {
756 		struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid;
757 		seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s',"
758 			   "date='%llu,%u'",
759 			   impl_id->name, impl_id->domain,
760 			   impl_id->date.seconds, impl_id->date.nseconds);
761 	}
762 }
763 #else
764 #if IS_ENABLED(CONFIG_NFS_V4)
765 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
766 {
767 }
768 #endif
769 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
770 {
771 }
772 #endif
773 
774 int nfs_show_devname(struct seq_file *m, struct dentry *root)
775 {
776 	char *page = (char *) __get_free_page(GFP_KERNEL);
777 	char *devname, *dummy;
778 	int err = 0;
779 	if (!page)
780 		return -ENOMEM;
781 	devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0);
782 	if (IS_ERR(devname))
783 		err = PTR_ERR(devname);
784 	else
785 		seq_escape(m, devname, " \t\n\\");
786 	free_page((unsigned long)page);
787 	return err;
788 }
789 EXPORT_SYMBOL_GPL(nfs_show_devname);
790 
791 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
792 {
793 	seq_puts(m, "/");
794 	return 0;
795 }
796 EXPORT_SYMBOL_GPL(nfs_show_path);
797 
798 /*
799  * Present statistical information for this VFS mountpoint
800  */
801 int nfs_show_stats(struct seq_file *m, struct dentry *root)
802 {
803 	int i, cpu;
804 	struct nfs_server *nfss = NFS_SB(root->d_sb);
805 	struct rpc_auth *auth = nfss->client->cl_auth;
806 	struct nfs_iostats totals = { };
807 
808 	seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS);
809 
810 	/*
811 	 * Display all mount option settings
812 	 */
813 	seq_printf(m, "\n\topts:\t");
814 	seq_puts(m, root->d_sb->s_flags & MS_RDONLY ? "ro" : "rw");
815 	seq_puts(m, root->d_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : "");
816 	seq_puts(m, root->d_sb->s_flags & MS_NOATIME ? ",noatime" : "");
817 	seq_puts(m, root->d_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : "");
818 	nfs_show_mount_options(m, nfss, 1);
819 
820 	seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ);
821 
822 	show_implementation_id(m, nfss);
823 
824 	seq_printf(m, "\n\tcaps:\t");
825 	seq_printf(m, "caps=0x%x", nfss->caps);
826 	seq_printf(m, ",wtmult=%u", nfss->wtmult);
827 	seq_printf(m, ",dtsize=%u", nfss->dtsize);
828 	seq_printf(m, ",bsize=%u", nfss->bsize);
829 	seq_printf(m, ",namlen=%u", nfss->namelen);
830 
831 #if IS_ENABLED(CONFIG_NFS_V4)
832 	if (nfss->nfs_client->rpc_ops->version == 4) {
833 		seq_printf(m, "\n\tnfsv4:\t");
834 		seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
835 		seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]);
836 		seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]);
837 		seq_printf(m, ",acl=0x%x", nfss->acl_bitmask);
838 		show_sessions(m, nfss);
839 		show_pnfs(m, nfss);
840 	}
841 #endif
842 
843 	/*
844 	 * Display security flavor in effect for this mount
845 	 */
846 	seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor);
847 	if (auth->au_flavor)
848 		seq_printf(m, ",pseudoflavor=%u", auth->au_flavor);
849 
850 	/*
851 	 * Display superblock I/O counters
852 	 */
853 	for_each_possible_cpu(cpu) {
854 		struct nfs_iostats *stats;
855 
856 		preempt_disable();
857 		stats = per_cpu_ptr(nfss->io_stats, cpu);
858 
859 		for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
860 			totals.events[i] += stats->events[i];
861 		for (i = 0; i < __NFSIOS_BYTESMAX; i++)
862 			totals.bytes[i] += stats->bytes[i];
863 #ifdef CONFIG_NFS_FSCACHE
864 		for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
865 			totals.fscache[i] += stats->fscache[i];
866 #endif
867 
868 		preempt_enable();
869 	}
870 
871 	seq_printf(m, "\n\tevents:\t");
872 	for (i = 0; i < __NFSIOS_COUNTSMAX; i++)
873 		seq_printf(m, "%lu ", totals.events[i]);
874 	seq_printf(m, "\n\tbytes:\t");
875 	for (i = 0; i < __NFSIOS_BYTESMAX; i++)
876 		seq_printf(m, "%Lu ", totals.bytes[i]);
877 #ifdef CONFIG_NFS_FSCACHE
878 	if (nfss->options & NFS_OPTION_FSCACHE) {
879 		seq_printf(m, "\n\tfsc:\t");
880 		for (i = 0; i < __NFSIOS_FSCACHEMAX; i++)
881 			seq_printf(m, "%Lu ", totals.bytes[i]);
882 	}
883 #endif
884 	seq_printf(m, "\n");
885 
886 	rpc_print_iostats(m, nfss->client);
887 
888 	return 0;
889 }
890 EXPORT_SYMBOL_GPL(nfs_show_stats);
891 
892 /*
893  * Begin unmount by attempting to remove all automounted mountpoints we added
894  * in response to xdev traversals and referrals
895  */
896 void nfs_umount_begin(struct super_block *sb)
897 {
898 	struct nfs_server *server;
899 	struct rpc_clnt *rpc;
900 
901 	server = NFS_SB(sb);
902 	/* -EIO all pending I/O */
903 	rpc = server->client_acl;
904 	if (!IS_ERR(rpc))
905 		rpc_killall_tasks(rpc);
906 	rpc = server->client;
907 	if (!IS_ERR(rpc))
908 		rpc_killall_tasks(rpc);
909 }
910 EXPORT_SYMBOL_GPL(nfs_umount_begin);
911 
912 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
913 {
914 	struct nfs_parsed_mount_data *data;
915 
916 	data = kzalloc(sizeof(*data), GFP_KERNEL);
917 	if (data) {
918 		data->acregmin		= NFS_DEF_ACREGMIN;
919 		data->acregmax		= NFS_DEF_ACREGMAX;
920 		data->acdirmin		= NFS_DEF_ACDIRMIN;
921 		data->acdirmax		= NFS_DEF_ACDIRMAX;
922 		data->mount_server.port	= NFS_UNSPEC_PORT;
923 		data->nfs_server.port	= NFS_UNSPEC_PORT;
924 		data->nfs_server.protocol = XPRT_TRANSPORT_TCP;
925 		data->auth_flavors[0]	= RPC_AUTH_MAXFLAVOR;
926 		data->auth_flavor_len	= 1;
927 		data->minorversion	= 0;
928 		data->need_mount	= true;
929 		data->net		= current->nsproxy->net_ns;
930 		security_init_mnt_opts(&data->lsm_opts);
931 	}
932 	return data;
933 }
934 
935 static void nfs_free_parsed_mount_data(struct nfs_parsed_mount_data *data)
936 {
937 	if (data) {
938 		kfree(data->client_address);
939 		kfree(data->mount_server.hostname);
940 		kfree(data->nfs_server.export_path);
941 		kfree(data->nfs_server.hostname);
942 		kfree(data->fscache_uniq);
943 		security_free_mnt_opts(&data->lsm_opts);
944 		kfree(data);
945 	}
946 }
947 
948 /*
949  * Sanity-check a server address provided by the mount command.
950  *
951  * Address family must be initialized, and address must not be
952  * the ANY address for that family.
953  */
954 static int nfs_verify_server_address(struct sockaddr *addr)
955 {
956 	switch (addr->sa_family) {
957 	case AF_INET: {
958 		struct sockaddr_in *sa = (struct sockaddr_in *)addr;
959 		return sa->sin_addr.s_addr != htonl(INADDR_ANY);
960 	}
961 	case AF_INET6: {
962 		struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
963 		return !ipv6_addr_any(sa);
964 	}
965 	}
966 
967 	dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
968 	return 0;
969 }
970 
971 /*
972  * Select between a default port value and a user-specified port value.
973  * If a zero value is set, then autobind will be used.
974  */
975 static void nfs_set_port(struct sockaddr *sap, int *port,
976 				 const unsigned short default_port)
977 {
978 	if (*port == NFS_UNSPEC_PORT)
979 		*port = default_port;
980 
981 	rpc_set_port(sap, *port);
982 }
983 
984 /*
985  * Sanity check the NFS transport protocol.
986  *
987  */
988 static void nfs_validate_transport_protocol(struct nfs_parsed_mount_data *mnt)
989 {
990 	switch (mnt->nfs_server.protocol) {
991 	case XPRT_TRANSPORT_UDP:
992 	case XPRT_TRANSPORT_TCP:
993 	case XPRT_TRANSPORT_RDMA:
994 		break;
995 	default:
996 		mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
997 	}
998 }
999 
1000 /*
1001  * For text based NFSv2/v3 mounts, the mount protocol transport default
1002  * settings should depend upon the specified NFS transport.
1003  */
1004 static void nfs_set_mount_transport_protocol(struct nfs_parsed_mount_data *mnt)
1005 {
1006 	nfs_validate_transport_protocol(mnt);
1007 
1008 	if (mnt->mount_server.protocol == XPRT_TRANSPORT_UDP ||
1009 	    mnt->mount_server.protocol == XPRT_TRANSPORT_TCP)
1010 			return;
1011 	switch (mnt->nfs_server.protocol) {
1012 	case XPRT_TRANSPORT_UDP:
1013 		mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1014 		break;
1015 	case XPRT_TRANSPORT_TCP:
1016 	case XPRT_TRANSPORT_RDMA:
1017 		mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1018 	}
1019 }
1020 
1021 /*
1022  * Parse the value of the 'sec=' option.
1023  */
1024 static int nfs_parse_security_flavors(char *value,
1025 				      struct nfs_parsed_mount_data *mnt)
1026 {
1027 	substring_t args[MAX_OPT_ARGS];
1028 
1029 	dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
1030 
1031 	switch (match_token(value, nfs_secflavor_tokens, args)) {
1032 	case Opt_sec_none:
1033 		mnt->auth_flavors[0] = RPC_AUTH_NULL;
1034 		break;
1035 	case Opt_sec_sys:
1036 		mnt->auth_flavors[0] = RPC_AUTH_UNIX;
1037 		break;
1038 	case Opt_sec_krb5:
1039 		mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5;
1040 		break;
1041 	case Opt_sec_krb5i:
1042 		mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5I;
1043 		break;
1044 	case Opt_sec_krb5p:
1045 		mnt->auth_flavors[0] = RPC_AUTH_GSS_KRB5P;
1046 		break;
1047 	case Opt_sec_lkey:
1048 		mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEY;
1049 		break;
1050 	case Opt_sec_lkeyi:
1051 		mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYI;
1052 		break;
1053 	case Opt_sec_lkeyp:
1054 		mnt->auth_flavors[0] = RPC_AUTH_GSS_LKEYP;
1055 		break;
1056 	case Opt_sec_spkm:
1057 		mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKM;
1058 		break;
1059 	case Opt_sec_spkmi:
1060 		mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMI;
1061 		break;
1062 	case Opt_sec_spkmp:
1063 		mnt->auth_flavors[0] = RPC_AUTH_GSS_SPKMP;
1064 		break;
1065 	default:
1066 		return 0;
1067 	}
1068 
1069 	mnt->flags |= NFS_MOUNT_SECFLAVOUR;
1070 	mnt->auth_flavor_len = 1;
1071 	return 1;
1072 }
1073 
1074 static int nfs_parse_version_string(char *string,
1075 		struct nfs_parsed_mount_data *mnt,
1076 		substring_t *args)
1077 {
1078 	mnt->flags &= ~NFS_MOUNT_VER3;
1079 	switch (match_token(string, nfs_vers_tokens, args)) {
1080 	case Opt_vers_2:
1081 		mnt->version = 2;
1082 		break;
1083 	case Opt_vers_3:
1084 		mnt->flags |= NFS_MOUNT_VER3;
1085 		mnt->version = 3;
1086 		break;
1087 	case Opt_vers_4:
1088 		/* Backward compatibility option. In future,
1089 		 * the mount program should always supply
1090 		 * a NFSv4 minor version number.
1091 		 */
1092 		mnt->version = 4;
1093 		break;
1094 	case Opt_vers_4_0:
1095 		mnt->version = 4;
1096 		mnt->minorversion = 0;
1097 		break;
1098 	case Opt_vers_4_1:
1099 		mnt->version = 4;
1100 		mnt->minorversion = 1;
1101 		break;
1102 	case Opt_vers_4_2:
1103 		mnt->version = 4;
1104 		mnt->minorversion = 2;
1105 		break;
1106 	default:
1107 		return 0;
1108 	}
1109 	return 1;
1110 }
1111 
1112 static int nfs_get_option_str(substring_t args[], char **option)
1113 {
1114 	kfree(*option);
1115 	*option = match_strdup(args);
1116 	return !*option;
1117 }
1118 
1119 static int nfs_get_option_ul(substring_t args[], unsigned long *option)
1120 {
1121 	int rc;
1122 	char *string;
1123 
1124 	string = match_strdup(args);
1125 	if (string == NULL)
1126 		return -ENOMEM;
1127 	rc = kstrtoul(string, 10, option);
1128 	kfree(string);
1129 
1130 	return rc;
1131 }
1132 
1133 /*
1134  * Error-check and convert a string of mount options from user space into
1135  * a data structure.  The whole mount string is processed; bad options are
1136  * skipped as they are encountered.  If there were no errors, return 1;
1137  * otherwise return 0 (zero).
1138  */
1139 static int nfs_parse_mount_options(char *raw,
1140 				   struct nfs_parsed_mount_data *mnt)
1141 {
1142 	char *p, *string, *secdata;
1143 	int rc, sloppy = 0, invalid_option = 0;
1144 	unsigned short protofamily = AF_UNSPEC;
1145 	unsigned short mountfamily = AF_UNSPEC;
1146 
1147 	if (!raw) {
1148 		dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
1149 		return 1;
1150 	}
1151 	dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
1152 
1153 	secdata = alloc_secdata();
1154 	if (!secdata)
1155 		goto out_nomem;
1156 
1157 	rc = security_sb_copy_data(raw, secdata);
1158 	if (rc)
1159 		goto out_security_failure;
1160 
1161 	rc = security_sb_parse_opts_str(secdata, &mnt->lsm_opts);
1162 	if (rc)
1163 		goto out_security_failure;
1164 
1165 	free_secdata(secdata);
1166 
1167 	while ((p = strsep(&raw, ",")) != NULL) {
1168 		substring_t args[MAX_OPT_ARGS];
1169 		unsigned long option;
1170 		int token;
1171 
1172 		if (!*p)
1173 			continue;
1174 
1175 		dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", p);
1176 
1177 		token = match_token(p, nfs_mount_option_tokens, args);
1178 		switch (token) {
1179 
1180 		/*
1181 		 * boolean options:  foo/nofoo
1182 		 */
1183 		case Opt_soft:
1184 			mnt->flags |= NFS_MOUNT_SOFT;
1185 			break;
1186 		case Opt_hard:
1187 			mnt->flags &= ~NFS_MOUNT_SOFT;
1188 			break;
1189 		case Opt_posix:
1190 			mnt->flags |= NFS_MOUNT_POSIX;
1191 			break;
1192 		case Opt_noposix:
1193 			mnt->flags &= ~NFS_MOUNT_POSIX;
1194 			break;
1195 		case Opt_cto:
1196 			mnt->flags &= ~NFS_MOUNT_NOCTO;
1197 			break;
1198 		case Opt_nocto:
1199 			mnt->flags |= NFS_MOUNT_NOCTO;
1200 			break;
1201 		case Opt_ac:
1202 			mnt->flags &= ~NFS_MOUNT_NOAC;
1203 			break;
1204 		case Opt_noac:
1205 			mnt->flags |= NFS_MOUNT_NOAC;
1206 			break;
1207 		case Opt_lock:
1208 			mnt->flags &= ~NFS_MOUNT_NONLM;
1209 			mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1210 					NFS_MOUNT_LOCAL_FCNTL);
1211 			break;
1212 		case Opt_nolock:
1213 			mnt->flags |= NFS_MOUNT_NONLM;
1214 			mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1215 				       NFS_MOUNT_LOCAL_FCNTL);
1216 			break;
1217 		case Opt_udp:
1218 			mnt->flags &= ~NFS_MOUNT_TCP;
1219 			mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1220 			break;
1221 		case Opt_tcp:
1222 			mnt->flags |= NFS_MOUNT_TCP;
1223 			mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1224 			break;
1225 		case Opt_rdma:
1226 			mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
1227 			mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1228 			xprt_load_transport(p);
1229 			break;
1230 		case Opt_acl:
1231 			mnt->flags &= ~NFS_MOUNT_NOACL;
1232 			break;
1233 		case Opt_noacl:
1234 			mnt->flags |= NFS_MOUNT_NOACL;
1235 			break;
1236 		case Opt_rdirplus:
1237 			mnt->flags &= ~NFS_MOUNT_NORDIRPLUS;
1238 			break;
1239 		case Opt_nordirplus:
1240 			mnt->flags |= NFS_MOUNT_NORDIRPLUS;
1241 			break;
1242 		case Opt_sharecache:
1243 			mnt->flags &= ~NFS_MOUNT_UNSHARED;
1244 			break;
1245 		case Opt_nosharecache:
1246 			mnt->flags |= NFS_MOUNT_UNSHARED;
1247 			break;
1248 		case Opt_resvport:
1249 			mnt->flags &= ~NFS_MOUNT_NORESVPORT;
1250 			break;
1251 		case Opt_noresvport:
1252 			mnt->flags |= NFS_MOUNT_NORESVPORT;
1253 			break;
1254 		case Opt_fscache:
1255 			mnt->options |= NFS_OPTION_FSCACHE;
1256 			kfree(mnt->fscache_uniq);
1257 			mnt->fscache_uniq = NULL;
1258 			break;
1259 		case Opt_nofscache:
1260 			mnt->options &= ~NFS_OPTION_FSCACHE;
1261 			kfree(mnt->fscache_uniq);
1262 			mnt->fscache_uniq = NULL;
1263 			break;
1264 		case Opt_migration:
1265 			mnt->options |= NFS_OPTION_MIGRATION;
1266 			break;
1267 		case Opt_nomigration:
1268 			mnt->options &= NFS_OPTION_MIGRATION;
1269 			break;
1270 
1271 		/*
1272 		 * options that take numeric values
1273 		 */
1274 		case Opt_port:
1275 			if (nfs_get_option_ul(args, &option) ||
1276 			    option > USHRT_MAX)
1277 				goto out_invalid_value;
1278 			mnt->nfs_server.port = option;
1279 			break;
1280 		case Opt_rsize:
1281 			if (nfs_get_option_ul(args, &option))
1282 				goto out_invalid_value;
1283 			mnt->rsize = option;
1284 			break;
1285 		case Opt_wsize:
1286 			if (nfs_get_option_ul(args, &option))
1287 				goto out_invalid_value;
1288 			mnt->wsize = option;
1289 			break;
1290 		case Opt_bsize:
1291 			if (nfs_get_option_ul(args, &option))
1292 				goto out_invalid_value;
1293 			mnt->bsize = option;
1294 			break;
1295 		case Opt_timeo:
1296 			if (nfs_get_option_ul(args, &option) || option == 0)
1297 				goto out_invalid_value;
1298 			mnt->timeo = option;
1299 			break;
1300 		case Opt_retrans:
1301 			if (nfs_get_option_ul(args, &option) || option == 0)
1302 				goto out_invalid_value;
1303 			mnt->retrans = option;
1304 			break;
1305 		case Opt_acregmin:
1306 			if (nfs_get_option_ul(args, &option))
1307 				goto out_invalid_value;
1308 			mnt->acregmin = option;
1309 			break;
1310 		case Opt_acregmax:
1311 			if (nfs_get_option_ul(args, &option))
1312 				goto out_invalid_value;
1313 			mnt->acregmax = option;
1314 			break;
1315 		case Opt_acdirmin:
1316 			if (nfs_get_option_ul(args, &option))
1317 				goto out_invalid_value;
1318 			mnt->acdirmin = option;
1319 			break;
1320 		case Opt_acdirmax:
1321 			if (nfs_get_option_ul(args, &option))
1322 				goto out_invalid_value;
1323 			mnt->acdirmax = option;
1324 			break;
1325 		case Opt_actimeo:
1326 			if (nfs_get_option_ul(args, &option))
1327 				goto out_invalid_value;
1328 			mnt->acregmin = mnt->acregmax =
1329 			mnt->acdirmin = mnt->acdirmax = option;
1330 			break;
1331 		case Opt_namelen:
1332 			if (nfs_get_option_ul(args, &option))
1333 				goto out_invalid_value;
1334 			mnt->namlen = option;
1335 			break;
1336 		case Opt_mountport:
1337 			if (nfs_get_option_ul(args, &option) ||
1338 			    option > USHRT_MAX)
1339 				goto out_invalid_value;
1340 			mnt->mount_server.port = option;
1341 			break;
1342 		case Opt_mountvers:
1343 			if (nfs_get_option_ul(args, &option) ||
1344 			    option < NFS_MNT_VERSION ||
1345 			    option > NFS_MNT3_VERSION)
1346 				goto out_invalid_value;
1347 			mnt->mount_server.version = option;
1348 			break;
1349 		case Opt_minorversion:
1350 			if (nfs_get_option_ul(args, &option))
1351 				goto out_invalid_value;
1352 			if (option > NFS4_MAX_MINOR_VERSION)
1353 				goto out_invalid_value;
1354 			mnt->minorversion = option;
1355 			break;
1356 
1357 		/*
1358 		 * options that take text values
1359 		 */
1360 		case Opt_nfsvers:
1361 			string = match_strdup(args);
1362 			if (string == NULL)
1363 				goto out_nomem;
1364 			rc = nfs_parse_version_string(string, mnt, args);
1365 			kfree(string);
1366 			if (!rc)
1367 				goto out_invalid_value;
1368 			break;
1369 		case Opt_sec:
1370 			string = match_strdup(args);
1371 			if (string == NULL)
1372 				goto out_nomem;
1373 			rc = nfs_parse_security_flavors(string, mnt);
1374 			kfree(string);
1375 			if (!rc) {
1376 				dfprintk(MOUNT, "NFS:   unrecognized "
1377 						"security flavor\n");
1378 				return 0;
1379 			}
1380 			break;
1381 		case Opt_proto:
1382 			string = match_strdup(args);
1383 			if (string == NULL)
1384 				goto out_nomem;
1385 			token = match_token(string,
1386 					    nfs_xprt_protocol_tokens, args);
1387 
1388 			protofamily = AF_INET;
1389 			switch (token) {
1390 			case Opt_xprt_udp6:
1391 				protofamily = AF_INET6;
1392 			case Opt_xprt_udp:
1393 				mnt->flags &= ~NFS_MOUNT_TCP;
1394 				mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1395 				break;
1396 			case Opt_xprt_tcp6:
1397 				protofamily = AF_INET6;
1398 			case Opt_xprt_tcp:
1399 				mnt->flags |= NFS_MOUNT_TCP;
1400 				mnt->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1401 				break;
1402 			case Opt_xprt_rdma:
1403 				/* vector side protocols to TCP */
1404 				mnt->flags |= NFS_MOUNT_TCP;
1405 				mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
1406 				xprt_load_transport(string);
1407 				break;
1408 			default:
1409 				dfprintk(MOUNT, "NFS:   unrecognized "
1410 						"transport protocol\n");
1411 				kfree(string);
1412 				return 0;
1413 			}
1414 			kfree(string);
1415 			break;
1416 		case Opt_mountproto:
1417 			string = match_strdup(args);
1418 			if (string == NULL)
1419 				goto out_nomem;
1420 			token = match_token(string,
1421 					    nfs_xprt_protocol_tokens, args);
1422 			kfree(string);
1423 
1424 			mountfamily = AF_INET;
1425 			switch (token) {
1426 			case Opt_xprt_udp6:
1427 				mountfamily = AF_INET6;
1428 			case Opt_xprt_udp:
1429 				mnt->mount_server.protocol = XPRT_TRANSPORT_UDP;
1430 				break;
1431 			case Opt_xprt_tcp6:
1432 				mountfamily = AF_INET6;
1433 			case Opt_xprt_tcp:
1434 				mnt->mount_server.protocol = XPRT_TRANSPORT_TCP;
1435 				break;
1436 			case Opt_xprt_rdma: /* not used for side protocols */
1437 			default:
1438 				dfprintk(MOUNT, "NFS:   unrecognized "
1439 						"transport protocol\n");
1440 				return 0;
1441 			}
1442 			break;
1443 		case Opt_addr:
1444 			string = match_strdup(args);
1445 			if (string == NULL)
1446 				goto out_nomem;
1447 			mnt->nfs_server.addrlen =
1448 				rpc_pton(mnt->net, string, strlen(string),
1449 					(struct sockaddr *)
1450 					&mnt->nfs_server.address,
1451 					sizeof(mnt->nfs_server.address));
1452 			kfree(string);
1453 			if (mnt->nfs_server.addrlen == 0)
1454 				goto out_invalid_address;
1455 			break;
1456 		case Opt_clientaddr:
1457 			if (nfs_get_option_str(args, &mnt->client_address))
1458 				goto out_nomem;
1459 			break;
1460 		case Opt_mounthost:
1461 			if (nfs_get_option_str(args,
1462 					       &mnt->mount_server.hostname))
1463 				goto out_nomem;
1464 			break;
1465 		case Opt_mountaddr:
1466 			string = match_strdup(args);
1467 			if (string == NULL)
1468 				goto out_nomem;
1469 			mnt->mount_server.addrlen =
1470 				rpc_pton(mnt->net, string, strlen(string),
1471 					(struct sockaddr *)
1472 					&mnt->mount_server.address,
1473 					sizeof(mnt->mount_server.address));
1474 			kfree(string);
1475 			if (mnt->mount_server.addrlen == 0)
1476 				goto out_invalid_address;
1477 			break;
1478 		case Opt_lookupcache:
1479 			string = match_strdup(args);
1480 			if (string == NULL)
1481 				goto out_nomem;
1482 			token = match_token(string,
1483 					nfs_lookupcache_tokens, args);
1484 			kfree(string);
1485 			switch (token) {
1486 				case Opt_lookupcache_all:
1487 					mnt->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
1488 					break;
1489 				case Opt_lookupcache_positive:
1490 					mnt->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
1491 					mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
1492 					break;
1493 				case Opt_lookupcache_none:
1494 					mnt->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
1495 					break;
1496 				default:
1497 					dfprintk(MOUNT, "NFS:   invalid "
1498 							"lookupcache argument\n");
1499 					return 0;
1500 			};
1501 			break;
1502 		case Opt_fscache_uniq:
1503 			if (nfs_get_option_str(args, &mnt->fscache_uniq))
1504 				goto out_nomem;
1505 			mnt->options |= NFS_OPTION_FSCACHE;
1506 			break;
1507 		case Opt_local_lock:
1508 			string = match_strdup(args);
1509 			if (string == NULL)
1510 				goto out_nomem;
1511 			token = match_token(string, nfs_local_lock_tokens,
1512 					args);
1513 			kfree(string);
1514 			switch (token) {
1515 			case Opt_local_lock_all:
1516 				mnt->flags |= (NFS_MOUNT_LOCAL_FLOCK |
1517 					       NFS_MOUNT_LOCAL_FCNTL);
1518 				break;
1519 			case Opt_local_lock_flock:
1520 				mnt->flags |= NFS_MOUNT_LOCAL_FLOCK;
1521 				break;
1522 			case Opt_local_lock_posix:
1523 				mnt->flags |= NFS_MOUNT_LOCAL_FCNTL;
1524 				break;
1525 			case Opt_local_lock_none:
1526 				mnt->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
1527 						NFS_MOUNT_LOCAL_FCNTL);
1528 				break;
1529 			default:
1530 				dfprintk(MOUNT, "NFS:	invalid	"
1531 						"local_lock argument\n");
1532 				return 0;
1533 			};
1534 			break;
1535 
1536 		/*
1537 		 * Special options
1538 		 */
1539 		case Opt_sloppy:
1540 			sloppy = 1;
1541 			dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
1542 			break;
1543 		case Opt_userspace:
1544 		case Opt_deprecated:
1545 			dfprintk(MOUNT, "NFS:   ignoring mount option "
1546 					"'%s'\n", p);
1547 			break;
1548 
1549 		default:
1550 			invalid_option = 1;
1551 			dfprintk(MOUNT, "NFS:   unrecognized mount option "
1552 					"'%s'\n", p);
1553 		}
1554 	}
1555 
1556 	if (!sloppy && invalid_option)
1557 		return 0;
1558 
1559 	if (mnt->minorversion && mnt->version != 4)
1560 		goto out_minorversion_mismatch;
1561 
1562 	if (mnt->options & NFS_OPTION_MIGRATION &&
1563 	    mnt->version != 4 && mnt->minorversion != 0)
1564 		goto out_migration_misuse;
1565 
1566 	/*
1567 	 * verify that any proto=/mountproto= options match the address
1568 	 * families in the addr=/mountaddr= options.
1569 	 */
1570 	if (protofamily != AF_UNSPEC &&
1571 	    protofamily != mnt->nfs_server.address.ss_family)
1572 		goto out_proto_mismatch;
1573 
1574 	if (mountfamily != AF_UNSPEC) {
1575 		if (mnt->mount_server.addrlen) {
1576 			if (mountfamily != mnt->mount_server.address.ss_family)
1577 				goto out_mountproto_mismatch;
1578 		} else {
1579 			if (mountfamily != mnt->nfs_server.address.ss_family)
1580 				goto out_mountproto_mismatch;
1581 		}
1582 	}
1583 
1584 	return 1;
1585 
1586 out_mountproto_mismatch:
1587 	printk(KERN_INFO "NFS: mount server address does not match mountproto= "
1588 			 "option\n");
1589 	return 0;
1590 out_proto_mismatch:
1591 	printk(KERN_INFO "NFS: server address does not match proto= option\n");
1592 	return 0;
1593 out_invalid_address:
1594 	printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
1595 	return 0;
1596 out_invalid_value:
1597 	printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
1598 	return 0;
1599 out_minorversion_mismatch:
1600 	printk(KERN_INFO "NFS: mount option vers=%u does not support "
1601 			 "minorversion=%u\n", mnt->version, mnt->minorversion);
1602 	return 0;
1603 out_migration_misuse:
1604 	printk(KERN_INFO
1605 		"NFS: 'migration' not supported for this NFS version\n");
1606 	return 0;
1607 out_nomem:
1608 	printk(KERN_INFO "NFS: not enough memory to parse option\n");
1609 	return 0;
1610 out_security_failure:
1611 	free_secdata(secdata);
1612 	printk(KERN_INFO "NFS: security options invalid: %d\n", rc);
1613 	return 0;
1614 }
1615 
1616 /*
1617  * Ensure that the specified authtype in args->auth_flavors[0] is supported by
1618  * the server. Returns 0 if it's ok, and -EACCES if not.
1619  */
1620 static int nfs_verify_authflavor(struct nfs_parsed_mount_data *args,
1621 			rpc_authflavor_t *server_authlist, unsigned int count)
1622 {
1623 	unsigned int i;
1624 
1625 	/*
1626 	 * If the sec= mount option is used, the specified flavor or AUTH_NULL
1627 	 * must be in the list returned by the server.
1628 	 *
1629 	 * AUTH_NULL has a special meaning when it's in the server list - it
1630 	 * means that the server will ignore the rpc creds, so any flavor
1631 	 * can be used.
1632 	 */
1633 	for (i = 0; i < count; i++) {
1634 		if (args->auth_flavors[0] == server_authlist[i] ||
1635 		    server_authlist[i] == RPC_AUTH_NULL)
1636 			goto out;
1637 	}
1638 
1639 	dfprintk(MOUNT, "NFS: auth flavor %u not supported by server\n",
1640 		args->auth_flavors[0]);
1641 	return -EACCES;
1642 
1643 out:
1644 	dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->auth_flavors[0]);
1645 	return 0;
1646 }
1647 
1648 /*
1649  * Use the remote server's MOUNT service to request the NFS file handle
1650  * corresponding to the provided path.
1651  */
1652 static int nfs_request_mount(struct nfs_parsed_mount_data *args,
1653 			     struct nfs_fh *root_fh,
1654 			     rpc_authflavor_t *server_authlist,
1655 			     unsigned int *server_authlist_len)
1656 {
1657 	struct nfs_mount_request request = {
1658 		.sap		= (struct sockaddr *)
1659 						&args->mount_server.address,
1660 		.dirpath	= args->nfs_server.export_path,
1661 		.protocol	= args->mount_server.protocol,
1662 		.fh		= root_fh,
1663 		.noresvport	= args->flags & NFS_MOUNT_NORESVPORT,
1664 		.auth_flav_len	= server_authlist_len,
1665 		.auth_flavs	= server_authlist,
1666 		.net		= args->net,
1667 	};
1668 	int status;
1669 
1670 	if (args->mount_server.version == 0) {
1671 		switch (args->version) {
1672 			default:
1673 				args->mount_server.version = NFS_MNT3_VERSION;
1674 				break;
1675 			case 2:
1676 				args->mount_server.version = NFS_MNT_VERSION;
1677 		}
1678 	}
1679 	request.version = args->mount_server.version;
1680 
1681 	if (args->mount_server.hostname)
1682 		request.hostname = args->mount_server.hostname;
1683 	else
1684 		request.hostname = args->nfs_server.hostname;
1685 
1686 	/*
1687 	 * Construct the mount server's address.
1688 	 */
1689 	if (args->mount_server.address.ss_family == AF_UNSPEC) {
1690 		memcpy(request.sap, &args->nfs_server.address,
1691 		       args->nfs_server.addrlen);
1692 		args->mount_server.addrlen = args->nfs_server.addrlen;
1693 	}
1694 	request.salen = args->mount_server.addrlen;
1695 	nfs_set_port(request.sap, &args->mount_server.port, 0);
1696 
1697 	/*
1698 	 * Now ask the mount server to map our export path
1699 	 * to a file handle.
1700 	 */
1701 	status = nfs_mount(&request);
1702 	if (status != 0) {
1703 		dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n",
1704 				request.hostname, status);
1705 		return status;
1706 	}
1707 
1708 	return 0;
1709 }
1710 
1711 static struct nfs_server *nfs_try_mount_request(struct nfs_mount_info *mount_info,
1712 					struct nfs_subversion *nfs_mod)
1713 {
1714 	int status;
1715 	unsigned int i;
1716 	bool tried_auth_unix = false;
1717 	bool auth_null_in_list = false;
1718 	struct nfs_server *server = ERR_PTR(-EACCES);
1719 	struct nfs_parsed_mount_data *args = mount_info->parsed;
1720 	rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS];
1721 	unsigned int authlist_len = ARRAY_SIZE(authlist);
1722 
1723 	status = nfs_request_mount(args, mount_info->mntfh, authlist,
1724 					&authlist_len);
1725 	if (status)
1726 		return ERR_PTR(status);
1727 
1728 	/*
1729 	 * Was a sec= authflavor specified in the options? First, verify
1730 	 * whether the server supports it, and then just try to use it if so.
1731 	 */
1732 	if (args->auth_flavors[0] != RPC_AUTH_MAXFLAVOR) {
1733 		status = nfs_verify_authflavor(args, authlist, authlist_len);
1734 		dfprintk(MOUNT, "NFS: using auth flavor %u\n", args->auth_flavors[0]);
1735 		if (status)
1736 			return ERR_PTR(status);
1737 		return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1738 	}
1739 
1740 	/*
1741 	 * No sec= option was provided. RFC 2623, section 2.7 suggests we
1742 	 * SHOULD prefer the flavor listed first. However, some servers list
1743 	 * AUTH_NULL first. Avoid ever choosing AUTH_NULL.
1744 	 */
1745 	for (i = 0; i < authlist_len; ++i) {
1746 		rpc_authflavor_t flavor;
1747 		struct rpcsec_gss_info info;
1748 
1749 		flavor = authlist[i];
1750 		switch (flavor) {
1751 		case RPC_AUTH_UNIX:
1752 			tried_auth_unix = true;
1753 			break;
1754 		case RPC_AUTH_NULL:
1755 			auth_null_in_list = true;
1756 			continue;
1757 		default:
1758 			if (rpcauth_get_gssinfo(flavor, &info) != 0)
1759 				continue;
1760 			/* Fallthrough */
1761 		}
1762 		dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor);
1763 		args->auth_flavors[0] = flavor;
1764 		server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1765 		if (!IS_ERR(server))
1766 			return server;
1767 	}
1768 
1769 	/*
1770 	 * Nothing we tried so far worked. At this point, give up if we've
1771 	 * already tried AUTH_UNIX or if the server's list doesn't contain
1772 	 * AUTH_NULL
1773 	 */
1774 	if (tried_auth_unix || !auth_null_in_list)
1775 		return server;
1776 
1777 	/* Last chance! Try AUTH_UNIX */
1778 	dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX);
1779 	args->auth_flavors[0] = RPC_AUTH_UNIX;
1780 	return nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1781 }
1782 
1783 struct dentry *nfs_try_mount(int flags, const char *dev_name,
1784 			     struct nfs_mount_info *mount_info,
1785 			     struct nfs_subversion *nfs_mod)
1786 {
1787 	struct nfs_server *server;
1788 
1789 	if (mount_info->parsed->need_mount)
1790 		server = nfs_try_mount_request(mount_info, nfs_mod);
1791 	else
1792 		server = nfs_mod->rpc_ops->create_server(mount_info, nfs_mod);
1793 
1794 	if (IS_ERR(server))
1795 		return ERR_CAST(server);
1796 
1797 	return nfs_fs_mount_common(server, flags, dev_name, mount_info, nfs_mod);
1798 }
1799 EXPORT_SYMBOL_GPL(nfs_try_mount);
1800 
1801 /*
1802  * Split "dev_name" into "hostname:export_path".
1803  *
1804  * The leftmost colon demarks the split between the server's hostname
1805  * and the export path.  If the hostname starts with a left square
1806  * bracket, then it may contain colons.
1807  *
1808  * Note: caller frees hostname and export path, even on error.
1809  */
1810 static int nfs_parse_devname(const char *dev_name,
1811 			     char **hostname, size_t maxnamlen,
1812 			     char **export_path, size_t maxpathlen)
1813 {
1814 	size_t len;
1815 	char *end;
1816 
1817 	/* Is the host name protected with square brakcets? */
1818 	if (*dev_name == '[') {
1819 		end = strchr(++dev_name, ']');
1820 		if (end == NULL || end[1] != ':')
1821 			goto out_bad_devname;
1822 
1823 		len = end - dev_name;
1824 		end++;
1825 	} else {
1826 		char *comma;
1827 
1828 		end = strchr(dev_name, ':');
1829 		if (end == NULL)
1830 			goto out_bad_devname;
1831 		len = end - dev_name;
1832 
1833 		/* kill possible hostname list: not supported */
1834 		comma = strchr(dev_name, ',');
1835 		if (comma != NULL && comma < end)
1836 			*comma = 0;
1837 	}
1838 
1839 	if (len > maxnamlen)
1840 		goto out_hostname;
1841 
1842 	/* N.B. caller will free nfs_server.hostname in all cases */
1843 	*hostname = kstrndup(dev_name, len, GFP_KERNEL);
1844 	if (*hostname == NULL)
1845 		goto out_nomem;
1846 	len = strlen(++end);
1847 	if (len > maxpathlen)
1848 		goto out_path;
1849 	*export_path = kstrndup(end, len, GFP_KERNEL);
1850 	if (!*export_path)
1851 		goto out_nomem;
1852 
1853 	dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
1854 	return 0;
1855 
1856 out_bad_devname:
1857 	dfprintk(MOUNT, "NFS: device name not in host:path format\n");
1858 	return -EINVAL;
1859 
1860 out_nomem:
1861 	dfprintk(MOUNT, "NFS: not enough memory to parse device name\n");
1862 	return -ENOMEM;
1863 
1864 out_hostname:
1865 	dfprintk(MOUNT, "NFS: server hostname too long\n");
1866 	return -ENAMETOOLONG;
1867 
1868 out_path:
1869 	dfprintk(MOUNT, "NFS: export pathname too long\n");
1870 	return -ENAMETOOLONG;
1871 }
1872 
1873 /*
1874  * Validate the NFS2/NFS3 mount data
1875  * - fills in the mount root filehandle
1876  *
1877  * For option strings, user space handles the following behaviors:
1878  *
1879  * + DNS: mapping server host name to IP address ("addr=" option)
1880  *
1881  * + failure mode: how to behave if a mount request can't be handled
1882  *   immediately ("fg/bg" option)
1883  *
1884  * + retry: how often to retry a mount request ("retry=" option)
1885  *
1886  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1887  *   mountproto=tcp after mountproto=udp, and so on
1888  */
1889 static int nfs23_validate_mount_data(void *options,
1890 				     struct nfs_parsed_mount_data *args,
1891 				     struct nfs_fh *mntfh,
1892 				     const char *dev_name)
1893 {
1894 	struct nfs_mount_data *data = (struct nfs_mount_data *)options;
1895 	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
1896 
1897 	if (data == NULL)
1898 		goto out_no_data;
1899 
1900 	args->version = NFS_DEFAULT_VERSION;
1901 	switch (data->version) {
1902 	case 1:
1903 		data->namlen = 0;
1904 	case 2:
1905 		data->bsize = 0;
1906 	case 3:
1907 		if (data->flags & NFS_MOUNT_VER3)
1908 			goto out_no_v3;
1909 		data->root.size = NFS2_FHSIZE;
1910 		memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1911 	case 4:
1912 		if (data->flags & NFS_MOUNT_SECFLAVOUR)
1913 			goto out_no_sec;
1914 	case 5:
1915 		memset(data->context, 0, sizeof(data->context));
1916 	case 6:
1917 		if (data->flags & NFS_MOUNT_VER3) {
1918 			if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1919 				goto out_invalid_fh;
1920 			mntfh->size = data->root.size;
1921 			args->version = 3;
1922 		} else {
1923 			mntfh->size = NFS2_FHSIZE;
1924 			args->version = 2;
1925 		}
1926 
1927 
1928 		memcpy(mntfh->data, data->root.data, mntfh->size);
1929 		if (mntfh->size < sizeof(mntfh->data))
1930 			memset(mntfh->data + mntfh->size, 0,
1931 			       sizeof(mntfh->data) - mntfh->size);
1932 
1933 		/*
1934 		 * Translate to nfs_parsed_mount_data, which nfs_fill_super
1935 		 * can deal with.
1936 		 */
1937 		args->flags		= data->flags & NFS_MOUNT_FLAGMASK;
1938 		args->flags		|= NFS_MOUNT_LEGACY_INTERFACE;
1939 		args->rsize		= data->rsize;
1940 		args->wsize		= data->wsize;
1941 		args->timeo		= data->timeo;
1942 		args->retrans		= data->retrans;
1943 		args->acregmin		= data->acregmin;
1944 		args->acregmax		= data->acregmax;
1945 		args->acdirmin		= data->acdirmin;
1946 		args->acdirmax		= data->acdirmax;
1947 		args->need_mount	= false;
1948 
1949 		memcpy(sap, &data->addr, sizeof(data->addr));
1950 		args->nfs_server.addrlen = sizeof(data->addr);
1951 		args->nfs_server.port = ntohs(data->addr.sin_port);
1952 		if (!nfs_verify_server_address(sap))
1953 			goto out_no_address;
1954 
1955 		if (!(data->flags & NFS_MOUNT_TCP))
1956 			args->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1957 		/* N.B. caller will free nfs_server.hostname in all cases */
1958 		args->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1959 		args->namlen		= data->namlen;
1960 		args->bsize		= data->bsize;
1961 
1962 		args->auth_flavors[0] = RPC_AUTH_UNIX;
1963 		if (data->flags & NFS_MOUNT_SECFLAVOUR)
1964 			args->auth_flavors[0] = data->pseudoflavor;
1965 		if (!args->nfs_server.hostname)
1966 			goto out_nomem;
1967 
1968 		if (!(data->flags & NFS_MOUNT_NONLM))
1969 			args->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1970 					 NFS_MOUNT_LOCAL_FCNTL);
1971 		else
1972 			args->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1973 					NFS_MOUNT_LOCAL_FCNTL);
1974 		/*
1975 		 * The legacy version 6 binary mount data from userspace has a
1976 		 * field used only to transport selinux information into the
1977 		 * the kernel.  To continue to support that functionality we
1978 		 * have a touch of selinux knowledge here in the NFS code. The
1979 		 * userspace code converted context=blah to just blah so we are
1980 		 * converting back to the full string selinux understands.
1981 		 */
1982 		if (data->context[0]){
1983 #ifdef CONFIG_SECURITY_SELINUX
1984 			int rc;
1985 			char *opts_str = kmalloc(sizeof(data->context) + 8, GFP_KERNEL);
1986 			if (!opts_str)
1987 				return -ENOMEM;
1988 			strcpy(opts_str, "context=");
1989 			data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1990 			strcat(opts_str, &data->context[0]);
1991 			rc = security_sb_parse_opts_str(opts_str, &args->lsm_opts);
1992 			kfree(opts_str);
1993 			if (rc)
1994 				return rc;
1995 #else
1996 			return -EINVAL;
1997 #endif
1998 		}
1999 
2000 		break;
2001 	default:
2002 		return NFS_TEXT_DATA;
2003 	}
2004 
2005 #if !IS_ENABLED(CONFIG_NFS_V3)
2006 	if (args->version == 3)
2007 		goto out_v3_not_compiled;
2008 #endif /* !CONFIG_NFS_V3 */
2009 
2010 	return 0;
2011 
2012 out_no_data:
2013 	dfprintk(MOUNT, "NFS: mount program didn't pass any mount data\n");
2014 	return -EINVAL;
2015 
2016 out_no_v3:
2017 	dfprintk(MOUNT, "NFS: nfs_mount_data version %d does not support v3\n",
2018 		 data->version);
2019 	return -EINVAL;
2020 
2021 out_no_sec:
2022 	dfprintk(MOUNT, "NFS: nfs_mount_data version supports only AUTH_SYS\n");
2023 	return -EINVAL;
2024 
2025 #if !IS_ENABLED(CONFIG_NFS_V3)
2026 out_v3_not_compiled:
2027 	dfprintk(MOUNT, "NFS: NFSv3 is not compiled into kernel\n");
2028 	return -EPROTONOSUPPORT;
2029 #endif /* !CONFIG_NFS_V3 */
2030 
2031 out_nomem:
2032 	dfprintk(MOUNT, "NFS: not enough memory to handle mount options\n");
2033 	return -ENOMEM;
2034 
2035 out_no_address:
2036 	dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2037 	return -EINVAL;
2038 
2039 out_invalid_fh:
2040 	dfprintk(MOUNT, "NFS: invalid root filehandle\n");
2041 	return -EINVAL;
2042 }
2043 
2044 #if IS_ENABLED(CONFIG_NFS_V4)
2045 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2046 				   void *options,
2047 				   struct nfs_parsed_mount_data *args,
2048 				   struct nfs_fh *mntfh,
2049 				   const char *dev_name)
2050 {
2051 	if (fs_type == &nfs_fs_type)
2052 		return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2053 	return nfs4_validate_mount_data(options, args, dev_name);
2054 }
2055 #else
2056 static int nfs_validate_mount_data(struct file_system_type *fs_type,
2057 				   void *options,
2058 				   struct nfs_parsed_mount_data *args,
2059 				   struct nfs_fh *mntfh,
2060 				   const char *dev_name)
2061 {
2062 	return nfs23_validate_mount_data(options, args, mntfh, dev_name);
2063 }
2064 #endif
2065 
2066 static int nfs_validate_text_mount_data(void *options,
2067 					struct nfs_parsed_mount_data *args,
2068 					const char *dev_name)
2069 {
2070 	int port = 0;
2071 	int max_namelen = PAGE_SIZE;
2072 	int max_pathlen = NFS_MAXPATHLEN;
2073 	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2074 
2075 	if (nfs_parse_mount_options((char *)options, args) == 0)
2076 		return -EINVAL;
2077 
2078 	if (!nfs_verify_server_address(sap))
2079 		goto out_no_address;
2080 
2081 	if (args->version == 4) {
2082 #if IS_ENABLED(CONFIG_NFS_V4)
2083 		port = NFS_PORT;
2084 		max_namelen = NFS4_MAXNAMLEN;
2085 		max_pathlen = NFS4_MAXPATHLEN;
2086 		nfs_validate_transport_protocol(args);
2087 		nfs4_validate_mount_flags(args);
2088 #else
2089 		goto out_v4_not_compiled;
2090 #endif /* CONFIG_NFS_V4 */
2091 	} else
2092 		nfs_set_mount_transport_protocol(args);
2093 
2094 	nfs_set_port(sap, &args->nfs_server.port, port);
2095 
2096 	if (args->auth_flavor_len > 1)
2097 		goto out_bad_auth;
2098 
2099 	return nfs_parse_devname(dev_name,
2100 				   &args->nfs_server.hostname,
2101 				   max_namelen,
2102 				   &args->nfs_server.export_path,
2103 				   max_pathlen);
2104 
2105 #if !IS_ENABLED(CONFIG_NFS_V4)
2106 out_v4_not_compiled:
2107 	dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
2108 	return -EPROTONOSUPPORT;
2109 #endif /* !CONFIG_NFS_V4 */
2110 
2111 out_no_address:
2112 	dfprintk(MOUNT, "NFS: mount program didn't pass remote address\n");
2113 	return -EINVAL;
2114 
2115 out_bad_auth:
2116 	dfprintk(MOUNT, "NFS: Too many RPC auth flavours specified\n");
2117 	return -EINVAL;
2118 }
2119 
2120 static int
2121 nfs_compare_remount_data(struct nfs_server *nfss,
2122 			 struct nfs_parsed_mount_data *data)
2123 {
2124 	if (data->flags != nfss->flags ||
2125 	    data->rsize != nfss->rsize ||
2126 	    data->wsize != nfss->wsize ||
2127 	    data->retrans != nfss->client->cl_timeout->to_retries ||
2128 	    data->auth_flavors[0] != nfss->client->cl_auth->au_flavor ||
2129 	    data->acregmin != nfss->acregmin / HZ ||
2130 	    data->acregmax != nfss->acregmax / HZ ||
2131 	    data->acdirmin != nfss->acdirmin / HZ ||
2132 	    data->acdirmax != nfss->acdirmax / HZ ||
2133 	    data->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) ||
2134 	    data->nfs_server.port != nfss->port ||
2135 	    data->nfs_server.addrlen != nfss->nfs_client->cl_addrlen ||
2136 	    !rpc_cmp_addr((struct sockaddr *)&data->nfs_server.address,
2137 			  (struct sockaddr *)&nfss->nfs_client->cl_addr))
2138 		return -EINVAL;
2139 
2140 	return 0;
2141 }
2142 
2143 int
2144 nfs_remount(struct super_block *sb, int *flags, char *raw_data)
2145 {
2146 	int error;
2147 	struct nfs_server *nfss = sb->s_fs_info;
2148 	struct nfs_parsed_mount_data *data;
2149 	struct nfs_mount_data *options = (struct nfs_mount_data *)raw_data;
2150 	struct nfs4_mount_data *options4 = (struct nfs4_mount_data *)raw_data;
2151 	u32 nfsvers = nfss->nfs_client->rpc_ops->version;
2152 
2153 	/*
2154 	 * Userspace mount programs that send binary options generally send
2155 	 * them populated with default values. We have no way to know which
2156 	 * ones were explicitly specified. Fall back to legacy behavior and
2157 	 * just return success.
2158 	 */
2159 	if ((nfsvers == 4 && (!options4 || options4->version == 1)) ||
2160 	    (nfsvers <= 3 && (!options || (options->version >= 1 &&
2161 					   options->version <= 6))))
2162 		return 0;
2163 
2164 	data = kzalloc(sizeof(*data), GFP_KERNEL);
2165 	if (data == NULL)
2166 		return -ENOMEM;
2167 
2168 	/* fill out struct with values from existing mount */
2169 	data->flags = nfss->flags;
2170 	data->rsize = nfss->rsize;
2171 	data->wsize = nfss->wsize;
2172 	data->retrans = nfss->client->cl_timeout->to_retries;
2173 	data->auth_flavors[0] = nfss->client->cl_auth->au_flavor;
2174 	data->acregmin = nfss->acregmin / HZ;
2175 	data->acregmax = nfss->acregmax / HZ;
2176 	data->acdirmin = nfss->acdirmin / HZ;
2177 	data->acdirmax = nfss->acdirmax / HZ;
2178 	data->timeo = 10U * nfss->client->cl_timeout->to_initval / HZ;
2179 	data->nfs_server.port = nfss->port;
2180 	data->nfs_server.addrlen = nfss->nfs_client->cl_addrlen;
2181 	memcpy(&data->nfs_server.address, &nfss->nfs_client->cl_addr,
2182 		data->nfs_server.addrlen);
2183 
2184 	/* overwrite those values with any that were specified */
2185 	error = nfs_parse_mount_options((char *)options, data);
2186 	if (error < 0)
2187 		goto out;
2188 
2189 	/*
2190 	 * noac is a special case. It implies -o sync, but that's not
2191 	 * necessarily reflected in the mtab options. do_remount_sb
2192 	 * will clear MS_SYNCHRONOUS if -o sync wasn't specified in the
2193 	 * remount options, so we have to explicitly reset it.
2194 	 */
2195 	if (data->flags & NFS_MOUNT_NOAC)
2196 		*flags |= MS_SYNCHRONOUS;
2197 
2198 	/* compare new mount options with old ones */
2199 	error = nfs_compare_remount_data(nfss, data);
2200 out:
2201 	kfree(data);
2202 	return error;
2203 }
2204 EXPORT_SYMBOL_GPL(nfs_remount);
2205 
2206 /*
2207  * Initialise the common bits of the superblock
2208  */
2209 inline void nfs_initialise_sb(struct super_block *sb)
2210 {
2211 	struct nfs_server *server = NFS_SB(sb);
2212 
2213 	sb->s_magic = NFS_SUPER_MAGIC;
2214 
2215 	/* We probably want something more informative here */
2216 	snprintf(sb->s_id, sizeof(sb->s_id),
2217 		 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev));
2218 
2219 	if (sb->s_blocksize == 0)
2220 		sb->s_blocksize = nfs_block_bits(server->wsize,
2221 						 &sb->s_blocksize_bits);
2222 
2223 	sb->s_bdi = &server->backing_dev_info;
2224 
2225 	nfs_super_set_maxbytes(sb, server->maxfilesize);
2226 }
2227 
2228 /*
2229  * Finish setting up an NFS2/3 superblock
2230  */
2231 void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2232 {
2233 	struct nfs_parsed_mount_data *data = mount_info->parsed;
2234 	struct nfs_server *server = NFS_SB(sb);
2235 
2236 	sb->s_blocksize_bits = 0;
2237 	sb->s_blocksize = 0;
2238 	sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr;
2239 	sb->s_op = server->nfs_client->cl_nfs_mod->sops;
2240 	if (data && data->bsize)
2241 		sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits);
2242 
2243 	if (server->nfs_client->rpc_ops->version != 2) {
2244 		/* The VFS shouldn't apply the umask to mode bits. We will do
2245 		 * so ourselves when necessary.
2246 		 */
2247 		sb->s_flags |= MS_POSIXACL;
2248 		sb->s_time_gran = 1;
2249 	}
2250 
2251  	nfs_initialise_sb(sb);
2252 }
2253 EXPORT_SYMBOL_GPL(nfs_fill_super);
2254 
2255 /*
2256  * Finish setting up a cloned NFS2/3/4 superblock
2257  */
2258 void nfs_clone_super(struct super_block *sb, struct nfs_mount_info *mount_info)
2259 {
2260 	const struct super_block *old_sb = mount_info->cloned->sb;
2261 	struct nfs_server *server = NFS_SB(sb);
2262 
2263 	sb->s_blocksize_bits = old_sb->s_blocksize_bits;
2264 	sb->s_blocksize = old_sb->s_blocksize;
2265 	sb->s_maxbytes = old_sb->s_maxbytes;
2266 	sb->s_xattr = old_sb->s_xattr;
2267 	sb->s_op = old_sb->s_op;
2268 	sb->s_time_gran = 1;
2269 
2270 	if (server->nfs_client->rpc_ops->version != 2) {
2271 		/* The VFS shouldn't apply the umask to mode bits. We will do
2272 		 * so ourselves when necessary.
2273 		 */
2274 		sb->s_flags |= MS_POSIXACL;
2275 	}
2276 
2277  	nfs_initialise_sb(sb);
2278 }
2279 
2280 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, int flags)
2281 {
2282 	const struct nfs_server *a = s->s_fs_info;
2283 	const struct rpc_clnt *clnt_a = a->client;
2284 	const struct rpc_clnt *clnt_b = b->client;
2285 
2286 	if ((s->s_flags & NFS_MS_MASK) != (flags & NFS_MS_MASK))
2287 		goto Ebusy;
2288 	if (a->nfs_client != b->nfs_client)
2289 		goto Ebusy;
2290 	if (a->flags != b->flags)
2291 		goto Ebusy;
2292 	if (a->wsize != b->wsize)
2293 		goto Ebusy;
2294 	if (a->rsize != b->rsize)
2295 		goto Ebusy;
2296 	if (a->acregmin != b->acregmin)
2297 		goto Ebusy;
2298 	if (a->acregmax != b->acregmax)
2299 		goto Ebusy;
2300 	if (a->acdirmin != b->acdirmin)
2301 		goto Ebusy;
2302 	if (a->acdirmax != b->acdirmax)
2303 		goto Ebusy;
2304 	if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor)
2305 		goto Ebusy;
2306 	return 1;
2307 Ebusy:
2308 	return 0;
2309 }
2310 
2311 struct nfs_sb_mountdata {
2312 	struct nfs_server *server;
2313 	int mntflags;
2314 };
2315 
2316 static int nfs_set_super(struct super_block *s, void *data)
2317 {
2318 	struct nfs_sb_mountdata *sb_mntdata = data;
2319 	struct nfs_server *server = sb_mntdata->server;
2320 	int ret;
2321 
2322 	s->s_flags = sb_mntdata->mntflags;
2323 	s->s_fs_info = server;
2324 	s->s_d_op = server->nfs_client->rpc_ops->dentry_ops;
2325 	ret = set_anon_super(s, server);
2326 	if (ret == 0)
2327 		server->s_dev = s->s_dev;
2328 	return ret;
2329 }
2330 
2331 static int nfs_compare_super_address(struct nfs_server *server1,
2332 				     struct nfs_server *server2)
2333 {
2334 	struct sockaddr *sap1, *sap2;
2335 
2336 	sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr;
2337 	sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr;
2338 
2339 	if (sap1->sa_family != sap2->sa_family)
2340 		return 0;
2341 
2342 	switch (sap1->sa_family) {
2343 	case AF_INET: {
2344 		struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1;
2345 		struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2;
2346 		if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr)
2347 			return 0;
2348 		if (sin1->sin_port != sin2->sin_port)
2349 			return 0;
2350 		break;
2351 	}
2352 	case AF_INET6: {
2353 		struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1;
2354 		struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2;
2355 		if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr))
2356 			return 0;
2357 		if (sin1->sin6_port != sin2->sin6_port)
2358 			return 0;
2359 		break;
2360 	}
2361 	default:
2362 		return 0;
2363 	}
2364 
2365 	return 1;
2366 }
2367 
2368 static int nfs_compare_super(struct super_block *sb, void *data)
2369 {
2370 	struct nfs_sb_mountdata *sb_mntdata = data;
2371 	struct nfs_server *server = sb_mntdata->server, *old = NFS_SB(sb);
2372 	int mntflags = sb_mntdata->mntflags;
2373 
2374 	if (!nfs_compare_super_address(old, server))
2375 		return 0;
2376 	/* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */
2377 	if (old->flags & NFS_MOUNT_UNSHARED)
2378 		return 0;
2379 	if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0)
2380 		return 0;
2381 	return nfs_compare_mount_options(sb, server, mntflags);
2382 }
2383 
2384 #ifdef CONFIG_NFS_FSCACHE
2385 static void nfs_get_cache_cookie(struct super_block *sb,
2386 				 struct nfs_parsed_mount_data *parsed,
2387 				 struct nfs_clone_mount *cloned)
2388 {
2389 	struct nfs_server *nfss = NFS_SB(sb);
2390 	char *uniq = NULL;
2391 	int ulen = 0;
2392 
2393 	nfss->fscache_key = NULL;
2394 	nfss->fscache = NULL;
2395 
2396 	if (parsed) {
2397 		if (!(parsed->options & NFS_OPTION_FSCACHE))
2398 			return;
2399 		if (parsed->fscache_uniq) {
2400 			uniq = parsed->fscache_uniq;
2401 			ulen = strlen(parsed->fscache_uniq);
2402 		}
2403 	} else if (cloned) {
2404 		struct nfs_server *mnt_s = NFS_SB(cloned->sb);
2405 		if (!(mnt_s->options & NFS_OPTION_FSCACHE))
2406 			return;
2407 		if (mnt_s->fscache_key) {
2408 			uniq = mnt_s->fscache_key->key.uniquifier;
2409 			ulen = mnt_s->fscache_key->key.uniq_len;
2410 		};
2411 	} else
2412 		return;
2413 
2414 	nfs_fscache_get_super_cookie(sb, uniq, ulen);
2415 }
2416 #else
2417 static void nfs_get_cache_cookie(struct super_block *sb,
2418 				 struct nfs_parsed_mount_data *parsed,
2419 				 struct nfs_clone_mount *cloned)
2420 {
2421 }
2422 #endif
2423 
2424 static int nfs_bdi_register(struct nfs_server *server)
2425 {
2426 	return bdi_register_dev(&server->backing_dev_info, server->s_dev);
2427 }
2428 
2429 int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
2430 			struct nfs_mount_info *mount_info)
2431 {
2432 	int error;
2433 	unsigned long kflags = 0, kflags_out = 0;
2434 	if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL)
2435 		kflags |= SECURITY_LSM_NATIVE_LABELS;
2436 
2437 	error = security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts,
2438 						kflags, &kflags_out);
2439 	if (error)
2440 		goto err;
2441 
2442 	if (NFS_SB(s)->caps & NFS_CAP_SECURITY_LABEL &&
2443 		!(kflags_out & SECURITY_LSM_NATIVE_LABELS))
2444 		NFS_SB(s)->caps &= ~NFS_CAP_SECURITY_LABEL;
2445 err:
2446 	return error;
2447 }
2448 EXPORT_SYMBOL_GPL(nfs_set_sb_security);
2449 
2450 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
2451 			  struct nfs_mount_info *mount_info)
2452 {
2453 	/* clone any lsm security options from the parent to the new sb */
2454 	if (mntroot->d_inode->i_op != NFS_SB(s)->nfs_client->rpc_ops->dir_inode_ops)
2455 		return -ESTALE;
2456 	return security_sb_clone_mnt_opts(mount_info->cloned->sb, s);
2457 }
2458 EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
2459 
2460 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
2461 				   int flags, const char *dev_name,
2462 				   struct nfs_mount_info *mount_info,
2463 				   struct nfs_subversion *nfs_mod)
2464 {
2465 	struct super_block *s;
2466 	struct dentry *mntroot = ERR_PTR(-ENOMEM);
2467 	int (*compare_super)(struct super_block *, void *) = nfs_compare_super;
2468 	struct nfs_sb_mountdata sb_mntdata = {
2469 		.mntflags = flags,
2470 		.server = server,
2471 	};
2472 	int error;
2473 
2474 	if (server->flags & NFS_MOUNT_UNSHARED)
2475 		compare_super = NULL;
2476 
2477 	/* -o noac implies -o sync */
2478 	if (server->flags & NFS_MOUNT_NOAC)
2479 		sb_mntdata.mntflags |= MS_SYNCHRONOUS;
2480 
2481 	/* Get a superblock - note that we may end up sharing one that already exists */
2482 	s = sget(nfs_mod->nfs_fs, compare_super, nfs_set_super, flags, &sb_mntdata);
2483 	if (IS_ERR(s)) {
2484 		mntroot = ERR_CAST(s);
2485 		goto out_err_nosb;
2486 	}
2487 
2488 	if (s->s_fs_info != server) {
2489 		nfs_free_server(server);
2490 		server = NULL;
2491 	} else {
2492 		error = nfs_bdi_register(server);
2493 		if (error) {
2494 			mntroot = ERR_PTR(error);
2495 			goto error_splat_bdi;
2496 		}
2497 	}
2498 
2499 	if (!s->s_root) {
2500 		/* initial superblock/root creation */
2501 		mount_info->fill_super(s, mount_info);
2502 		nfs_get_cache_cookie(s, mount_info->parsed, mount_info->cloned);
2503 	}
2504 
2505 	mntroot = nfs_get_root(s, mount_info->mntfh, dev_name);
2506 	if (IS_ERR(mntroot))
2507 		goto error_splat_super;
2508 
2509 	error = mount_info->set_security(s, mntroot, mount_info);
2510 	if (error)
2511 		goto error_splat_root;
2512 
2513 	s->s_flags |= MS_ACTIVE;
2514 
2515 out:
2516 	return mntroot;
2517 
2518 out_err_nosb:
2519 	nfs_free_server(server);
2520 	goto out;
2521 
2522 error_splat_root:
2523 	dput(mntroot);
2524 	mntroot = ERR_PTR(error);
2525 error_splat_super:
2526 	if (server && !s->s_root)
2527 		bdi_unregister(&server->backing_dev_info);
2528 error_splat_bdi:
2529 	deactivate_locked_super(s);
2530 	goto out;
2531 }
2532 EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
2533 
2534 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
2535 	int flags, const char *dev_name, void *raw_data)
2536 {
2537 	struct nfs_mount_info mount_info = {
2538 		.fill_super = nfs_fill_super,
2539 		.set_security = nfs_set_sb_security,
2540 	};
2541 	struct dentry *mntroot = ERR_PTR(-ENOMEM);
2542 	struct nfs_subversion *nfs_mod;
2543 	int error;
2544 
2545 	mount_info.parsed = nfs_alloc_parsed_mount_data();
2546 	mount_info.mntfh = nfs_alloc_fhandle();
2547 	if (mount_info.parsed == NULL || mount_info.mntfh == NULL)
2548 		goto out;
2549 
2550 	/* Validate the mount data */
2551 	error = nfs_validate_mount_data(fs_type, raw_data, mount_info.parsed, mount_info.mntfh, dev_name);
2552 	if (error == NFS_TEXT_DATA)
2553 		error = nfs_validate_text_mount_data(raw_data, mount_info.parsed, dev_name);
2554 	if (error < 0) {
2555 		mntroot = ERR_PTR(error);
2556 		goto out;
2557 	}
2558 
2559 	nfs_mod = get_nfs_version(mount_info.parsed->version);
2560 	if (IS_ERR(nfs_mod)) {
2561 		mntroot = ERR_CAST(nfs_mod);
2562 		goto out;
2563 	}
2564 
2565 	mntroot = nfs_mod->rpc_ops->try_mount(flags, dev_name, &mount_info, nfs_mod);
2566 
2567 	put_nfs_version(nfs_mod);
2568 out:
2569 	nfs_free_parsed_mount_data(mount_info.parsed);
2570 	nfs_free_fhandle(mount_info.mntfh);
2571 	return mntroot;
2572 }
2573 EXPORT_SYMBOL_GPL(nfs_fs_mount);
2574 
2575 /*
2576  * Ensure that we unregister the bdi before kill_anon_super
2577  * releases the device name
2578  */
2579 void nfs_put_super(struct super_block *s)
2580 {
2581 	struct nfs_server *server = NFS_SB(s);
2582 
2583 	bdi_unregister(&server->backing_dev_info);
2584 }
2585 EXPORT_SYMBOL_GPL(nfs_put_super);
2586 
2587 /*
2588  * Destroy an NFS2/3 superblock
2589  */
2590 void nfs_kill_super(struct super_block *s)
2591 {
2592 	struct nfs_server *server = NFS_SB(s);
2593 
2594 	kill_anon_super(s);
2595 	nfs_fscache_release_super_cookie(s);
2596 	nfs_free_server(server);
2597 }
2598 EXPORT_SYMBOL_GPL(nfs_kill_super);
2599 
2600 /*
2601  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
2602  */
2603 static struct dentry *
2604 nfs_xdev_mount(struct file_system_type *fs_type, int flags,
2605 		const char *dev_name, void *raw_data)
2606 {
2607 	struct nfs_clone_mount *data = raw_data;
2608 	struct nfs_mount_info mount_info = {
2609 		.fill_super = nfs_clone_super,
2610 		.set_security = nfs_clone_sb_security,
2611 		.cloned = data,
2612 	};
2613 	struct nfs_server *server;
2614 	struct dentry *mntroot = ERR_PTR(-ENOMEM);
2615 	struct nfs_subversion *nfs_mod = NFS_SB(data->sb)->nfs_client->cl_nfs_mod;
2616 
2617 	dprintk("--> nfs_xdev_mount()\n");
2618 
2619 	mount_info.mntfh = mount_info.cloned->fh;
2620 
2621 	/* create a new volume representation */
2622 	server = nfs_mod->rpc_ops->clone_server(NFS_SB(data->sb), data->fh, data->fattr, data->authflavor);
2623 
2624 	if (IS_ERR(server))
2625 		mntroot = ERR_CAST(server);
2626 	else
2627 		mntroot = nfs_fs_mount_common(server, flags,
2628 				dev_name, &mount_info, nfs_mod);
2629 
2630 	dprintk("<-- nfs_xdev_mount() = %ld\n",
2631 			IS_ERR(mntroot) ? PTR_ERR(mntroot) : 0L);
2632 	return mntroot;
2633 }
2634 
2635 #if IS_ENABLED(CONFIG_NFS_V4)
2636 
2637 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
2638 {
2639 	args->flags &= ~(NFS_MOUNT_NONLM|NFS_MOUNT_NOACL|NFS_MOUNT_VER3|
2640 			 NFS_MOUNT_LOCAL_FLOCK|NFS_MOUNT_LOCAL_FCNTL);
2641 }
2642 
2643 /*
2644  * Validate NFSv4 mount options
2645  */
2646 static int nfs4_validate_mount_data(void *options,
2647 				    struct nfs_parsed_mount_data *args,
2648 				    const char *dev_name)
2649 {
2650 	struct sockaddr *sap = (struct sockaddr *)&args->nfs_server.address;
2651 	struct nfs4_mount_data *data = (struct nfs4_mount_data *)options;
2652 	char *c;
2653 
2654 	if (data == NULL)
2655 		goto out_no_data;
2656 
2657 	args->version = 4;
2658 
2659 	switch (data->version) {
2660 	case 1:
2661 		if (data->host_addrlen > sizeof(args->nfs_server.address))
2662 			goto out_no_address;
2663 		if (data->host_addrlen == 0)
2664 			goto out_no_address;
2665 		args->nfs_server.addrlen = data->host_addrlen;
2666 		if (copy_from_user(sap, data->host_addr, data->host_addrlen))
2667 			return -EFAULT;
2668 		if (!nfs_verify_server_address(sap))
2669 			goto out_no_address;
2670 		args->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
2671 
2672 		args->auth_flavors[0] = RPC_AUTH_UNIX;
2673 		if (data->auth_flavourlen) {
2674 			if (data->auth_flavourlen > 1)
2675 				goto out_inval_auth;
2676 			if (copy_from_user(&args->auth_flavors[0],
2677 					   data->auth_flavours,
2678 					   sizeof(args->auth_flavors[0])))
2679 				return -EFAULT;
2680 		}
2681 
2682 		c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
2683 		if (IS_ERR(c))
2684 			return PTR_ERR(c);
2685 		args->nfs_server.hostname = c;
2686 
2687 		c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
2688 		if (IS_ERR(c))
2689 			return PTR_ERR(c);
2690 		args->nfs_server.export_path = c;
2691 		dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
2692 
2693 		c = strndup_user(data->client_addr.data, 16);
2694 		if (IS_ERR(c))
2695 			return PTR_ERR(c);
2696 		args->client_address = c;
2697 
2698 		/*
2699 		 * Translate to nfs_parsed_mount_data, which nfs4_fill_super
2700 		 * can deal with.
2701 		 */
2702 
2703 		args->flags	= data->flags & NFS4_MOUNT_FLAGMASK;
2704 		args->rsize	= data->rsize;
2705 		args->wsize	= data->wsize;
2706 		args->timeo	= data->timeo;
2707 		args->retrans	= data->retrans;
2708 		args->acregmin	= data->acregmin;
2709 		args->acregmax	= data->acregmax;
2710 		args->acdirmin	= data->acdirmin;
2711 		args->acdirmax	= data->acdirmax;
2712 		args->nfs_server.protocol = data->proto;
2713 		nfs_validate_transport_protocol(args);
2714 
2715 		break;
2716 	default:
2717 		return NFS_TEXT_DATA;
2718 	}
2719 
2720 	return 0;
2721 
2722 out_no_data:
2723 	dfprintk(MOUNT, "NFS4: mount program didn't pass any mount data\n");
2724 	return -EINVAL;
2725 
2726 out_inval_auth:
2727 	dfprintk(MOUNT, "NFS4: Invalid number of RPC auth flavours %d\n",
2728 		 data->auth_flavourlen);
2729 	return -EINVAL;
2730 
2731 out_no_address:
2732 	dfprintk(MOUNT, "NFS4: mount program didn't pass remote address\n");
2733 	return -EINVAL;
2734 }
2735 
2736 /*
2737  * NFS v4 module parameters need to stay in the
2738  * NFS client for backwards compatibility
2739  */
2740 unsigned int nfs_callback_set_tcpport;
2741 unsigned short nfs_callback_tcpport;
2742 /* Default cache timeout is 10 minutes */
2743 unsigned int nfs_idmap_cache_timeout = 600;
2744 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */
2745 bool nfs4_disable_idmapping = true;
2746 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
2747 unsigned short send_implementation_id = 1;
2748 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = "";
2749 
2750 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
2751 EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
2752 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
2753 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
2754 EXPORT_SYMBOL_GPL(max_session_slots);
2755 EXPORT_SYMBOL_GPL(send_implementation_id);
2756 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier);
2757 
2758 #define NFS_CALLBACK_MAXPORTNR (65535U)
2759 
2760 static int param_set_portnr(const char *val, const struct kernel_param *kp)
2761 {
2762 	unsigned long num;
2763 	int ret;
2764 
2765 	if (!val)
2766 		return -EINVAL;
2767 	ret = kstrtoul(val, 0, &num);
2768 	if (ret == -EINVAL || num > NFS_CALLBACK_MAXPORTNR)
2769 		return -EINVAL;
2770 	*((unsigned int *)kp->arg) = num;
2771 	return 0;
2772 }
2773 static struct kernel_param_ops param_ops_portnr = {
2774 	.set = param_set_portnr,
2775 	.get = param_get_uint,
2776 };
2777 #define param_check_portnr(name, p) __param_check(name, p, unsigned int);
2778 
2779 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644);
2780 module_param(nfs_idmap_cache_timeout, int, 0644);
2781 module_param(nfs4_disable_idmapping, bool, 0644);
2782 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier,
2783 			NFS4_CLIENT_ID_UNIQ_LEN, 0600);
2784 MODULE_PARM_DESC(nfs4_disable_idmapping,
2785 		"Turn off NFSv4 idmapping when using 'sec=sys'");
2786 module_param(max_session_slots, ushort, 0644);
2787 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 "
2788 		"requests the client will negotiate");
2789 module_param(send_implementation_id, ushort, 0644);
2790 MODULE_PARM_DESC(send_implementation_id,
2791 		"Send implementation ID with NFSv4.1 exchange_id");
2792 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string");
2793 
2794 #endif /* CONFIG_NFS_V4 */
2795