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