xref: /kernel/linux/linux-5.10/fs/nfs/fs_context.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/fs/nfs/fs_context.c
4 *
5 * Copyright (C) 1992 Rick Sladkey
6 * Conversion to new mount api Copyright (C) David Howells
7 *
8 * NFS mount handling.
9 *
10 * Split from fs/nfs/super.c by David Howells <dhowells@redhat.com>
11 */
12
13#include <linux/module.h>
14#include <linux/fs.h>
15#include <linux/fs_context.h>
16#include <linux/fs_parser.h>
17#include <linux/nfs_fs.h>
18#include <linux/nfs_mount.h>
19#include <linux/nfs4_mount.h>
20#include "nfs.h"
21#include "internal.h"
22
23#define NFSDBG_FACILITY		NFSDBG_MOUNT
24
25#if IS_ENABLED(CONFIG_NFS_V3)
26#define NFS_DEFAULT_VERSION 3
27#else
28#define NFS_DEFAULT_VERSION 2
29#endif
30
31#define NFS_MAX_CONNECTIONS 16
32
33enum nfs_param {
34	Opt_ac,
35	Opt_acdirmax,
36	Opt_acdirmin,
37	Opt_acl,
38	Opt_acregmax,
39	Opt_acregmin,
40	Opt_actimeo,
41	Opt_addr,
42	Opt_bg,
43	Opt_bsize,
44	Opt_clientaddr,
45	Opt_cto,
46	Opt_fg,
47	Opt_fscache,
48	Opt_fscache_flag,
49	Opt_hard,
50	Opt_intr,
51	Opt_local_lock,
52	Opt_lock,
53	Opt_lookupcache,
54	Opt_migration,
55	Opt_minorversion,
56	Opt_mountaddr,
57	Opt_mounthost,
58	Opt_mountport,
59	Opt_mountproto,
60	Opt_mountvers,
61	Opt_namelen,
62	Opt_nconnect,
63	Opt_port,
64	Opt_posix,
65	Opt_proto,
66	Opt_rdirplus,
67	Opt_rdma,
68	Opt_resvport,
69	Opt_retrans,
70	Opt_retry,
71	Opt_rsize,
72	Opt_sec,
73	Opt_sharecache,
74	Opt_sloppy,
75	Opt_soft,
76	Opt_softerr,
77	Opt_softreval,
78	Opt_source,
79	Opt_tcp,
80	Opt_timeo,
81	Opt_udp,
82	Opt_v,
83	Opt_vers,
84	Opt_wsize,
85};
86
87enum {
88	Opt_local_lock_all,
89	Opt_local_lock_flock,
90	Opt_local_lock_none,
91	Opt_local_lock_posix,
92};
93
94static const struct constant_table nfs_param_enums_local_lock[] = {
95	{ "all",		Opt_local_lock_all },
96	{ "flock",	Opt_local_lock_flock },
97	{ "posix",	Opt_local_lock_posix },
98	{ "none",		Opt_local_lock_none },
99	{}
100};
101
102enum {
103	Opt_lookupcache_all,
104	Opt_lookupcache_none,
105	Opt_lookupcache_positive,
106};
107
108static const struct constant_table nfs_param_enums_lookupcache[] = {
109	{ "all",		Opt_lookupcache_all },
110	{ "none",		Opt_lookupcache_none },
111	{ "pos",		Opt_lookupcache_positive },
112	{ "positive",		Opt_lookupcache_positive },
113	{}
114};
115
116static const struct fs_parameter_spec nfs_fs_parameters[] = {
117	fsparam_flag_no("ac",		Opt_ac),
118	fsparam_u32   ("acdirmax",	Opt_acdirmax),
119	fsparam_u32   ("acdirmin",	Opt_acdirmin),
120	fsparam_flag_no("acl",		Opt_acl),
121	fsparam_u32   ("acregmax",	Opt_acregmax),
122	fsparam_u32   ("acregmin",	Opt_acregmin),
123	fsparam_u32   ("actimeo",	Opt_actimeo),
124	fsparam_string("addr",		Opt_addr),
125	fsparam_flag  ("bg",		Opt_bg),
126	fsparam_u32   ("bsize",		Opt_bsize),
127	fsparam_string("clientaddr",	Opt_clientaddr),
128	fsparam_flag_no("cto",		Opt_cto),
129	fsparam_flag  ("fg",		Opt_fg),
130	fsparam_flag_no("fsc",		Opt_fscache_flag),
131	fsparam_string("fsc",		Opt_fscache),
132	fsparam_flag  ("hard",		Opt_hard),
133	__fsparam(NULL, "intr",		Opt_intr,
134		  fs_param_neg_with_no|fs_param_deprecated, NULL),
135	fsparam_enum  ("local_lock",	Opt_local_lock, nfs_param_enums_local_lock),
136	fsparam_flag_no("lock",		Opt_lock),
137	fsparam_enum  ("lookupcache",	Opt_lookupcache, nfs_param_enums_lookupcache),
138	fsparam_flag_no("migration",	Opt_migration),
139	fsparam_u32   ("minorversion",	Opt_minorversion),
140	fsparam_string("mountaddr",	Opt_mountaddr),
141	fsparam_string("mounthost",	Opt_mounthost),
142	fsparam_u32   ("mountport",	Opt_mountport),
143	fsparam_string("mountproto",	Opt_mountproto),
144	fsparam_u32   ("mountvers",	Opt_mountvers),
145	fsparam_u32   ("namlen",	Opt_namelen),
146	fsparam_u32   ("nconnect",	Opt_nconnect),
147	fsparam_string("nfsvers",	Opt_vers),
148	fsparam_u32   ("port",		Opt_port),
149	fsparam_flag_no("posix",	Opt_posix),
150	fsparam_string("proto",		Opt_proto),
151	fsparam_flag_no("rdirplus",	Opt_rdirplus),
152	fsparam_flag  ("rdma",		Opt_rdma),
153	fsparam_flag_no("resvport",	Opt_resvport),
154	fsparam_u32   ("retrans",	Opt_retrans),
155	fsparam_string("retry",		Opt_retry),
156	fsparam_u32   ("rsize",		Opt_rsize),
157	fsparam_string("sec",		Opt_sec),
158	fsparam_flag_no("sharecache",	Opt_sharecache),
159	fsparam_flag  ("sloppy",	Opt_sloppy),
160	fsparam_flag  ("soft",		Opt_soft),
161	fsparam_flag  ("softerr",	Opt_softerr),
162	fsparam_flag  ("softreval",	Opt_softreval),
163	fsparam_string("source",	Opt_source),
164	fsparam_flag  ("tcp",		Opt_tcp),
165	fsparam_u32   ("timeo",		Opt_timeo),
166	fsparam_flag  ("udp",		Opt_udp),
167	fsparam_flag  ("v2",		Opt_v),
168	fsparam_flag  ("v3",		Opt_v),
169	fsparam_flag  ("v4",		Opt_v),
170	fsparam_flag  ("v4.0",		Opt_v),
171	fsparam_flag  ("v4.1",		Opt_v),
172	fsparam_flag  ("v4.2",		Opt_v),
173	fsparam_string("vers",		Opt_vers),
174	fsparam_u32   ("wsize",		Opt_wsize),
175	{}
176};
177
178enum {
179	Opt_vers_2,
180	Opt_vers_3,
181	Opt_vers_4,
182	Opt_vers_4_0,
183	Opt_vers_4_1,
184	Opt_vers_4_2,
185};
186
187static const struct constant_table nfs_vers_tokens[] = {
188	{ "2",		Opt_vers_2 },
189	{ "3",		Opt_vers_3 },
190	{ "4",		Opt_vers_4 },
191	{ "4.0",	Opt_vers_4_0 },
192	{ "4.1",	Opt_vers_4_1 },
193	{ "4.2",	Opt_vers_4_2 },
194	{}
195};
196
197enum {
198	Opt_xprt_rdma,
199	Opt_xprt_rdma6,
200	Opt_xprt_tcp,
201	Opt_xprt_tcp6,
202	Opt_xprt_udp,
203	Opt_xprt_udp6,
204	nr__Opt_xprt
205};
206
207static const struct constant_table nfs_xprt_protocol_tokens[] = {
208	{ "rdma",	Opt_xprt_rdma },
209	{ "rdma6",	Opt_xprt_rdma6 },
210	{ "tcp",	Opt_xprt_tcp },
211	{ "tcp6",	Opt_xprt_tcp6 },
212	{ "udp",	Opt_xprt_udp },
213	{ "udp6",	Opt_xprt_udp6 },
214	{}
215};
216
217enum {
218	Opt_sec_krb5,
219	Opt_sec_krb5i,
220	Opt_sec_krb5p,
221	Opt_sec_lkey,
222	Opt_sec_lkeyi,
223	Opt_sec_lkeyp,
224	Opt_sec_none,
225	Opt_sec_spkm,
226	Opt_sec_spkmi,
227	Opt_sec_spkmp,
228	Opt_sec_sys,
229	nr__Opt_sec
230};
231
232static const struct constant_table nfs_secflavor_tokens[] = {
233	{ "krb5",	Opt_sec_krb5 },
234	{ "krb5i",	Opt_sec_krb5i },
235	{ "krb5p",	Opt_sec_krb5p },
236	{ "lkey",	Opt_sec_lkey },
237	{ "lkeyi",	Opt_sec_lkeyi },
238	{ "lkeyp",	Opt_sec_lkeyp },
239	{ "none",	Opt_sec_none },
240	{ "null",	Opt_sec_none },
241	{ "spkm3",	Opt_sec_spkm },
242	{ "spkm3i",	Opt_sec_spkmi },
243	{ "spkm3p",	Opt_sec_spkmp },
244	{ "sys",	Opt_sec_sys },
245	{}
246};
247
248/*
249 * Sanity-check a server address provided by the mount command.
250 *
251 * Address family must be initialized, and address must not be
252 * the ANY address for that family.
253 */
254static int nfs_verify_server_address(struct sockaddr *addr)
255{
256	switch (addr->sa_family) {
257	case AF_INET: {
258		struct sockaddr_in *sa = (struct sockaddr_in *)addr;
259		return sa->sin_addr.s_addr != htonl(INADDR_ANY);
260	}
261	case AF_INET6: {
262		struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
263		return !ipv6_addr_any(sa);
264	}
265	}
266
267	dfprintk(MOUNT, "NFS: Invalid IP address specified\n");
268	return 0;
269}
270
271/*
272 * Sanity check the NFS transport protocol.
273 *
274 */
275static void nfs_validate_transport_protocol(struct nfs_fs_context *ctx)
276{
277	switch (ctx->nfs_server.protocol) {
278	case XPRT_TRANSPORT_UDP:
279	case XPRT_TRANSPORT_TCP:
280	case XPRT_TRANSPORT_RDMA:
281		break;
282	default:
283		ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
284	}
285}
286
287/*
288 * For text based NFSv2/v3 mounts, the mount protocol transport default
289 * settings should depend upon the specified NFS transport.
290 */
291static void nfs_set_mount_transport_protocol(struct nfs_fs_context *ctx)
292{
293	nfs_validate_transport_protocol(ctx);
294
295	if (ctx->mount_server.protocol == XPRT_TRANSPORT_UDP ||
296	    ctx->mount_server.protocol == XPRT_TRANSPORT_TCP)
297			return;
298	switch (ctx->nfs_server.protocol) {
299	case XPRT_TRANSPORT_UDP:
300		ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
301		break;
302	case XPRT_TRANSPORT_TCP:
303	case XPRT_TRANSPORT_RDMA:
304		ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
305	}
306}
307
308/*
309 * Add 'flavor' to 'auth_info' if not already present.
310 * Returns true if 'flavor' ends up in the list, false otherwise
311 */
312static int nfs_auth_info_add(struct fs_context *fc,
313			     struct nfs_auth_info *auth_info,
314			     rpc_authflavor_t flavor)
315{
316	unsigned int i;
317	unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
318
319	/* make sure this flavor isn't already in the list */
320	for (i = 0; i < auth_info->flavor_len; i++) {
321		if (flavor == auth_info->flavors[i])
322			return 0;
323	}
324
325	if (auth_info->flavor_len + 1 >= max_flavor_len)
326		return nfs_invalf(fc, "NFS: too many sec= flavors");
327
328	auth_info->flavors[auth_info->flavor_len++] = flavor;
329	return 0;
330}
331
332/*
333 * Parse the value of the 'sec=' option.
334 */
335static int nfs_parse_security_flavors(struct fs_context *fc,
336				      struct fs_parameter *param)
337{
338	struct nfs_fs_context *ctx = nfs_fc2context(fc);
339	rpc_authflavor_t pseudoflavor;
340	char *string = param->string, *p;
341	int ret;
342
343	dfprintk(MOUNT, "NFS: parsing %s=%s option\n", param->key, param->string);
344
345	while ((p = strsep(&string, ":")) != NULL) {
346		if (!*p)
347			continue;
348		switch (lookup_constant(nfs_secflavor_tokens, p, -1)) {
349		case Opt_sec_none:
350			pseudoflavor = RPC_AUTH_NULL;
351			break;
352		case Opt_sec_sys:
353			pseudoflavor = RPC_AUTH_UNIX;
354			break;
355		case Opt_sec_krb5:
356			pseudoflavor = RPC_AUTH_GSS_KRB5;
357			break;
358		case Opt_sec_krb5i:
359			pseudoflavor = RPC_AUTH_GSS_KRB5I;
360			break;
361		case Opt_sec_krb5p:
362			pseudoflavor = RPC_AUTH_GSS_KRB5P;
363			break;
364		case Opt_sec_lkey:
365			pseudoflavor = RPC_AUTH_GSS_LKEY;
366			break;
367		case Opt_sec_lkeyi:
368			pseudoflavor = RPC_AUTH_GSS_LKEYI;
369			break;
370		case Opt_sec_lkeyp:
371			pseudoflavor = RPC_AUTH_GSS_LKEYP;
372			break;
373		case Opt_sec_spkm:
374			pseudoflavor = RPC_AUTH_GSS_SPKM;
375			break;
376		case Opt_sec_spkmi:
377			pseudoflavor = RPC_AUTH_GSS_SPKMI;
378			break;
379		case Opt_sec_spkmp:
380			pseudoflavor = RPC_AUTH_GSS_SPKMP;
381			break;
382		default:
383			return nfs_invalf(fc, "NFS: sec=%s option not recognized", p);
384		}
385
386		ret = nfs_auth_info_add(fc, &ctx->auth_info, pseudoflavor);
387		if (ret < 0)
388			return ret;
389	}
390
391	return 0;
392}
393
394static int nfs_parse_version_string(struct fs_context *fc,
395				    const char *string)
396{
397	struct nfs_fs_context *ctx = nfs_fc2context(fc);
398
399	ctx->flags &= ~NFS_MOUNT_VER3;
400	switch (lookup_constant(nfs_vers_tokens, string, -1)) {
401	case Opt_vers_2:
402		ctx->version = 2;
403		break;
404	case Opt_vers_3:
405		ctx->flags |= NFS_MOUNT_VER3;
406		ctx->version = 3;
407		break;
408	case Opt_vers_4:
409		/* Backward compatibility option. In future,
410		 * the mount program should always supply
411		 * a NFSv4 minor version number.
412		 */
413		ctx->version = 4;
414		break;
415	case Opt_vers_4_0:
416		ctx->version = 4;
417		ctx->minorversion = 0;
418		break;
419	case Opt_vers_4_1:
420		ctx->version = 4;
421		ctx->minorversion = 1;
422		break;
423	case Opt_vers_4_2:
424		ctx->version = 4;
425		ctx->minorversion = 2;
426		break;
427	default:
428		return nfs_invalf(fc, "NFS: Unsupported NFS version");
429	}
430	return 0;
431}
432
433/*
434 * Parse a single mount parameter.
435 */
436static int nfs_fs_context_parse_param(struct fs_context *fc,
437				      struct fs_parameter *param)
438{
439	struct fs_parse_result result;
440	struct nfs_fs_context *ctx = nfs_fc2context(fc);
441	unsigned short protofamily, mountfamily;
442	unsigned int len;
443	int ret, opt;
444
445	dfprintk(MOUNT, "NFS:   parsing nfs mount option '%s'\n", param->key);
446
447	opt = fs_parse(fc, nfs_fs_parameters, param, &result);
448	if (opt < 0)
449		return ctx->sloppy ? 1 : opt;
450
451	switch (opt) {
452	case Opt_source:
453		if (fc->source)
454			return nfs_invalf(fc, "NFS: Multiple sources not supported");
455		fc->source = param->string;
456		param->string = NULL;
457		break;
458
459		/*
460		 * boolean options:  foo/nofoo
461		 */
462	case Opt_soft:
463		ctx->flags |= NFS_MOUNT_SOFT;
464		ctx->flags &= ~NFS_MOUNT_SOFTERR;
465		break;
466	case Opt_softerr:
467		ctx->flags |= NFS_MOUNT_SOFTERR | NFS_MOUNT_SOFTREVAL;
468		ctx->flags &= ~NFS_MOUNT_SOFT;
469		break;
470	case Opt_hard:
471		ctx->flags &= ~(NFS_MOUNT_SOFT |
472				NFS_MOUNT_SOFTERR |
473				NFS_MOUNT_SOFTREVAL);
474		break;
475	case Opt_softreval:
476		if (result.negated)
477			ctx->flags &= ~NFS_MOUNT_SOFTREVAL;
478		else
479			ctx->flags |= NFS_MOUNT_SOFTREVAL;
480		break;
481	case Opt_posix:
482		if (result.negated)
483			ctx->flags &= ~NFS_MOUNT_POSIX;
484		else
485			ctx->flags |= NFS_MOUNT_POSIX;
486		break;
487	case Opt_cto:
488		if (result.negated)
489			ctx->flags |= NFS_MOUNT_NOCTO;
490		else
491			ctx->flags &= ~NFS_MOUNT_NOCTO;
492		break;
493	case Opt_ac:
494		if (result.negated)
495			ctx->flags |= NFS_MOUNT_NOAC;
496		else
497			ctx->flags &= ~NFS_MOUNT_NOAC;
498		break;
499	case Opt_lock:
500		if (result.negated) {
501			ctx->flags |= NFS_MOUNT_NONLM;
502			ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
503		} else {
504			ctx->flags &= ~NFS_MOUNT_NONLM;
505			ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
506		}
507		break;
508	case Opt_udp:
509		ctx->flags &= ~NFS_MOUNT_TCP;
510		ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
511		break;
512	case Opt_tcp:
513		ctx->flags |= NFS_MOUNT_TCP;
514		ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
515		break;
516	case Opt_rdma:
517		ctx->flags |= NFS_MOUNT_TCP; /* for side protocols */
518		ctx->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
519		xprt_load_transport(param->key);
520		break;
521	case Opt_acl:
522		if (result.negated)
523			ctx->flags |= NFS_MOUNT_NOACL;
524		else
525			ctx->flags &= ~NFS_MOUNT_NOACL;
526		break;
527	case Opt_rdirplus:
528		if (result.negated)
529			ctx->flags |= NFS_MOUNT_NORDIRPLUS;
530		else
531			ctx->flags &= ~NFS_MOUNT_NORDIRPLUS;
532		break;
533	case Opt_sharecache:
534		if (result.negated)
535			ctx->flags |= NFS_MOUNT_UNSHARED;
536		else
537			ctx->flags &= ~NFS_MOUNT_UNSHARED;
538		break;
539	case Opt_resvport:
540		if (result.negated)
541			ctx->flags |= NFS_MOUNT_NORESVPORT;
542		else
543			ctx->flags &= ~NFS_MOUNT_NORESVPORT;
544		break;
545	case Opt_fscache_flag:
546		if (result.negated)
547			ctx->options &= ~NFS_OPTION_FSCACHE;
548		else
549			ctx->options |= NFS_OPTION_FSCACHE;
550		kfree(ctx->fscache_uniq);
551		ctx->fscache_uniq = NULL;
552		break;
553	case Opt_fscache:
554		ctx->options |= NFS_OPTION_FSCACHE;
555		kfree(ctx->fscache_uniq);
556		ctx->fscache_uniq = param->string;
557		param->string = NULL;
558		break;
559	case Opt_migration:
560		if (result.negated)
561			ctx->options &= ~NFS_OPTION_MIGRATION;
562		else
563			ctx->options |= NFS_OPTION_MIGRATION;
564		break;
565
566		/*
567		 * options that take numeric values
568		 */
569	case Opt_port:
570		if (result.uint_32 > USHRT_MAX)
571			goto out_of_bounds;
572		ctx->nfs_server.port = result.uint_32;
573		break;
574	case Opt_rsize:
575		ctx->rsize = result.uint_32;
576		break;
577	case Opt_wsize:
578		ctx->wsize = result.uint_32;
579		break;
580	case Opt_bsize:
581		ctx->bsize = result.uint_32;
582		break;
583	case Opt_timeo:
584		if (result.uint_32 < 1 || result.uint_32 > INT_MAX)
585			goto out_of_bounds;
586		ctx->timeo = result.uint_32;
587		break;
588	case Opt_retrans:
589		if (result.uint_32 > INT_MAX)
590			goto out_of_bounds;
591		ctx->retrans = result.uint_32;
592		break;
593	case Opt_acregmin:
594		ctx->acregmin = result.uint_32;
595		break;
596	case Opt_acregmax:
597		ctx->acregmax = result.uint_32;
598		break;
599	case Opt_acdirmin:
600		ctx->acdirmin = result.uint_32;
601		break;
602	case Opt_acdirmax:
603		ctx->acdirmax = result.uint_32;
604		break;
605	case Opt_actimeo:
606		ctx->acregmin = result.uint_32;
607		ctx->acregmax = result.uint_32;
608		ctx->acdirmin = result.uint_32;
609		ctx->acdirmax = result.uint_32;
610		break;
611	case Opt_namelen:
612		ctx->namlen = result.uint_32;
613		break;
614	case Opt_mountport:
615		if (result.uint_32 > USHRT_MAX)
616			goto out_of_bounds;
617		ctx->mount_server.port = result.uint_32;
618		break;
619	case Opt_mountvers:
620		if (result.uint_32 < NFS_MNT_VERSION ||
621		    result.uint_32 > NFS_MNT3_VERSION)
622			goto out_of_bounds;
623		ctx->mount_server.version = result.uint_32;
624		break;
625	case Opt_minorversion:
626		if (result.uint_32 > NFS4_MAX_MINOR_VERSION)
627			goto out_of_bounds;
628		ctx->minorversion = result.uint_32;
629		break;
630
631		/*
632		 * options that take text values
633		 */
634	case Opt_v:
635		ret = nfs_parse_version_string(fc, param->key + 1);
636		if (ret < 0)
637			return ret;
638		break;
639	case Opt_vers:
640		ret = nfs_parse_version_string(fc, param->string);
641		if (ret < 0)
642			return ret;
643		break;
644	case Opt_sec:
645		ret = nfs_parse_security_flavors(fc, param);
646		if (ret < 0)
647			return ret;
648		break;
649
650	case Opt_proto:
651		protofamily = AF_INET;
652		switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
653		case Opt_xprt_udp6:
654			protofamily = AF_INET6;
655			fallthrough;
656		case Opt_xprt_udp:
657			ctx->flags &= ~NFS_MOUNT_TCP;
658			ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
659			break;
660		case Opt_xprt_tcp6:
661			protofamily = AF_INET6;
662			fallthrough;
663		case Opt_xprt_tcp:
664			ctx->flags |= NFS_MOUNT_TCP;
665			ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
666			break;
667		case Opt_xprt_rdma6:
668			protofamily = AF_INET6;
669			fallthrough;
670		case Opt_xprt_rdma:
671			/* vector side protocols to TCP */
672			ctx->flags |= NFS_MOUNT_TCP;
673			ctx->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
674			xprt_load_transport(param->string);
675			break;
676		default:
677			return nfs_invalf(fc, "NFS: Unrecognized transport protocol");
678		}
679
680		ctx->protofamily = protofamily;
681		break;
682
683	case Opt_mountproto:
684		mountfamily = AF_INET;
685		switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
686		case Opt_xprt_udp6:
687			mountfamily = AF_INET6;
688			fallthrough;
689		case Opt_xprt_udp:
690			ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
691			break;
692		case Opt_xprt_tcp6:
693			mountfamily = AF_INET6;
694			fallthrough;
695		case Opt_xprt_tcp:
696			ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
697			break;
698		case Opt_xprt_rdma: /* not used for side protocols */
699		default:
700			return nfs_invalf(fc, "NFS: Unrecognized transport protocol");
701		}
702		ctx->mountfamily = mountfamily;
703		break;
704
705	case Opt_addr:
706		len = rpc_pton(fc->net_ns, param->string, param->size,
707			       &ctx->nfs_server.address,
708			       sizeof(ctx->nfs_server._address));
709		if (len == 0)
710			goto out_invalid_address;
711		ctx->nfs_server.addrlen = len;
712		break;
713	case Opt_clientaddr:
714		kfree(ctx->client_address);
715		ctx->client_address = param->string;
716		param->string = NULL;
717		break;
718	case Opt_mounthost:
719		kfree(ctx->mount_server.hostname);
720		ctx->mount_server.hostname = param->string;
721		param->string = NULL;
722		break;
723	case Opt_mountaddr:
724		len = rpc_pton(fc->net_ns, param->string, param->size,
725			       &ctx->mount_server.address,
726			       sizeof(ctx->mount_server._address));
727		if (len == 0)
728			goto out_invalid_address;
729		ctx->mount_server.addrlen = len;
730		break;
731	case Opt_nconnect:
732		if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_CONNECTIONS)
733			goto out_of_bounds;
734		ctx->nfs_server.nconnect = result.uint_32;
735		break;
736	case Opt_lookupcache:
737		switch (result.uint_32) {
738		case Opt_lookupcache_all:
739			ctx->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
740			break;
741		case Opt_lookupcache_positive:
742			ctx->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
743			ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
744			break;
745		case Opt_lookupcache_none:
746			ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
747			break;
748		default:
749			goto out_invalid_value;
750		}
751		break;
752	case Opt_local_lock:
753		switch (result.uint_32) {
754		case Opt_local_lock_all:
755			ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK |
756				       NFS_MOUNT_LOCAL_FCNTL);
757			break;
758		case Opt_local_lock_flock:
759			ctx->flags |= NFS_MOUNT_LOCAL_FLOCK;
760			break;
761		case Opt_local_lock_posix:
762			ctx->flags |= NFS_MOUNT_LOCAL_FCNTL;
763			break;
764		case Opt_local_lock_none:
765			ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
766					NFS_MOUNT_LOCAL_FCNTL);
767			break;
768		default:
769			goto out_invalid_value;
770		}
771		break;
772
773		/*
774		 * Special options
775		 */
776	case Opt_sloppy:
777		ctx->sloppy = true;
778		dfprintk(MOUNT, "NFS:   relaxing parsing rules\n");
779		break;
780	}
781
782	return 0;
783
784out_invalid_value:
785	return nfs_invalf(fc, "NFS: Bad mount option value specified");
786out_invalid_address:
787	return nfs_invalf(fc, "NFS: Bad IP address specified");
788out_of_bounds:
789	return nfs_invalf(fc, "NFS: Value for '%s' out of range", param->key);
790}
791
792/*
793 * Split fc->source into "hostname:export_path".
794 *
795 * The leftmost colon demarks the split between the server's hostname
796 * and the export path.  If the hostname starts with a left square
797 * bracket, then it may contain colons.
798 *
799 * Note: caller frees hostname and export path, even on error.
800 */
801static int nfs_parse_source(struct fs_context *fc,
802			    size_t maxnamlen, size_t maxpathlen)
803{
804	struct nfs_fs_context *ctx = nfs_fc2context(fc);
805	const char *dev_name = fc->source;
806	size_t len;
807	const char *end;
808
809	if (unlikely(!dev_name || !*dev_name)) {
810		dfprintk(MOUNT, "NFS: device name not specified\n");
811		return -EINVAL;
812	}
813
814	/* Is the host name protected with square brakcets? */
815	if (*dev_name == '[') {
816		end = strchr(++dev_name, ']');
817		if (end == NULL || end[1] != ':')
818			goto out_bad_devname;
819
820		len = end - dev_name;
821		end++;
822	} else {
823		const char *comma;
824
825		end = strchr(dev_name, ':');
826		if (end == NULL)
827			goto out_bad_devname;
828		len = end - dev_name;
829
830		/* kill possible hostname list: not supported */
831		comma = memchr(dev_name, ',', len);
832		if (comma)
833			len = comma - dev_name;
834	}
835
836	if (len > maxnamlen)
837		goto out_hostname;
838
839	kfree(ctx->nfs_server.hostname);
840
841	/* N.B. caller will free nfs_server.hostname in all cases */
842	ctx->nfs_server.hostname = kmemdup_nul(dev_name, len, GFP_KERNEL);
843	if (!ctx->nfs_server.hostname)
844		goto out_nomem;
845	len = strlen(++end);
846	if (len > maxpathlen)
847		goto out_path;
848	ctx->nfs_server.export_path = kmemdup_nul(end, len, GFP_KERNEL);
849	if (!ctx->nfs_server.export_path)
850		goto out_nomem;
851
852	dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", ctx->nfs_server.export_path);
853	return 0;
854
855out_bad_devname:
856	return nfs_invalf(fc, "NFS: device name not in host:path format");
857out_nomem:
858	nfs_errorf(fc, "NFS: not enough memory to parse device name");
859	return -ENOMEM;
860out_hostname:
861	nfs_errorf(fc, "NFS: server hostname too long");
862	return -ENAMETOOLONG;
863out_path:
864	nfs_errorf(fc, "NFS: export pathname too long");
865	return -ENAMETOOLONG;
866}
867
868static inline bool is_remount_fc(struct fs_context *fc)
869{
870	return fc->root != NULL;
871}
872
873/*
874 * Parse monolithic NFS2/NFS3 mount data
875 * - fills in the mount root filehandle
876 *
877 * For option strings, user space handles the following behaviors:
878 *
879 * + DNS: mapping server host name to IP address ("addr=" option)
880 *
881 * + failure mode: how to behave if a mount request can't be handled
882 *   immediately ("fg/bg" option)
883 *
884 * + retry: how often to retry a mount request ("retry=" option)
885 *
886 * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
887 *   mountproto=tcp after mountproto=udp, and so on
888 */
889static int nfs23_parse_monolithic(struct fs_context *fc,
890				  struct nfs_mount_data *data)
891{
892	struct nfs_fs_context *ctx = nfs_fc2context(fc);
893	struct nfs_fh *mntfh = ctx->mntfh;
894	struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
895	int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
896
897	if (data == NULL)
898		goto out_no_data;
899
900	ctx->version = NFS_DEFAULT_VERSION;
901	switch (data->version) {
902	case 1:
903		data->namlen = 0;
904		fallthrough;
905	case 2:
906		data->bsize = 0;
907		fallthrough;
908	case 3:
909		if (data->flags & NFS_MOUNT_VER3)
910			goto out_no_v3;
911		data->root.size = NFS2_FHSIZE;
912		memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
913		/* Turn off security negotiation */
914		extra_flags |= NFS_MOUNT_SECFLAVOUR;
915		fallthrough;
916	case 4:
917		if (data->flags & NFS_MOUNT_SECFLAVOUR)
918			goto out_no_sec;
919		fallthrough;
920	case 5:
921		memset(data->context, 0, sizeof(data->context));
922		fallthrough;
923	case 6:
924		if (data->flags & NFS_MOUNT_VER3) {
925			if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
926				goto out_invalid_fh;
927			mntfh->size = data->root.size;
928			ctx->version = 3;
929		} else {
930			mntfh->size = NFS2_FHSIZE;
931			ctx->version = 2;
932		}
933
934
935		memcpy(mntfh->data, data->root.data, mntfh->size);
936		if (mntfh->size < sizeof(mntfh->data))
937			memset(mntfh->data + mntfh->size, 0,
938			       sizeof(mntfh->data) - mntfh->size);
939
940		/*
941		 * for proto == XPRT_TRANSPORT_UDP, which is what uses
942		 * to_exponential, implying shift: limit the shift value
943		 * to BITS_PER_LONG (majortimeo is unsigned long)
944		 */
945		if (!(data->flags & NFS_MOUNT_TCP)) /* this will be UDP */
946			if (data->retrans >= 64) /* shift value is too large */
947				goto out_invalid_data;
948
949		/*
950		 * Translate to nfs_fs_context, which nfs_fill_super
951		 * can deal with.
952		 */
953		ctx->flags	= data->flags & NFS_MOUNT_FLAGMASK;
954		ctx->flags	|= extra_flags;
955		ctx->rsize	= data->rsize;
956		ctx->wsize	= data->wsize;
957		ctx->timeo	= data->timeo;
958		ctx->retrans	= data->retrans;
959		ctx->acregmin	= data->acregmin;
960		ctx->acregmax	= data->acregmax;
961		ctx->acdirmin	= data->acdirmin;
962		ctx->acdirmax	= data->acdirmax;
963		ctx->need_mount	= false;
964
965		memcpy(sap, &data->addr, sizeof(data->addr));
966		ctx->nfs_server.addrlen = sizeof(data->addr);
967		ctx->nfs_server.port = ntohs(data->addr.sin_port);
968		if (sap->sa_family != AF_INET ||
969		    !nfs_verify_server_address(sap))
970			goto out_no_address;
971
972		if (!(data->flags & NFS_MOUNT_TCP))
973			ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
974		/* N.B. caller will free nfs_server.hostname in all cases */
975		ctx->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
976		if (!ctx->nfs_server.hostname)
977			goto out_nomem;
978
979		ctx->namlen		= data->namlen;
980		ctx->bsize		= data->bsize;
981
982		if (data->flags & NFS_MOUNT_SECFLAVOUR)
983			ctx->selected_flavor = data->pseudoflavor;
984		else
985			ctx->selected_flavor = RPC_AUTH_UNIX;
986
987		if (!(data->flags & NFS_MOUNT_NONLM))
988			ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
989					 NFS_MOUNT_LOCAL_FCNTL);
990		else
991			ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK|
992					NFS_MOUNT_LOCAL_FCNTL);
993
994		/*
995		 * The legacy version 6 binary mount data from userspace has a
996		 * field used only to transport selinux information into the
997		 * kernel.  To continue to support that functionality we
998		 * have a touch of selinux knowledge here in the NFS code. The
999		 * userspace code converted context=blah to just blah so we are
1000		 * converting back to the full string selinux understands.
1001		 */
1002		if (data->context[0]){
1003#ifdef CONFIG_SECURITY_SELINUX
1004			int ret;
1005
1006			data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1007			ret = vfs_parse_fs_string(fc, "context",
1008						  data->context, strlen(data->context));
1009			if (ret < 0)
1010				return ret;
1011#else
1012			return -EINVAL;
1013#endif
1014		}
1015
1016		break;
1017	default:
1018		goto generic;
1019	}
1020
1021	ctx->skip_reconfig_option_check = true;
1022	return 0;
1023
1024generic:
1025	return generic_parse_monolithic(fc, data);
1026
1027out_no_data:
1028	if (is_remount_fc(fc)) {
1029		ctx->skip_reconfig_option_check = true;
1030		return 0;
1031	}
1032	return nfs_invalf(fc, "NFS: mount program didn't pass any mount data");
1033
1034out_no_v3:
1035	return nfs_invalf(fc, "NFS: nfs_mount_data version does not support v3");
1036
1037out_no_sec:
1038	return nfs_invalf(fc, "NFS: nfs_mount_data version supports only AUTH_SYS");
1039
1040out_nomem:
1041	dfprintk(MOUNT, "NFS: not enough memory to handle mount options");
1042	return -ENOMEM;
1043
1044out_no_address:
1045	return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1046
1047out_invalid_fh:
1048	return nfs_invalf(fc, "NFS: invalid root filehandle");
1049
1050out_invalid_data:
1051	return nfs_invalf(fc, "NFS: invalid binary mount data");
1052}
1053
1054#if IS_ENABLED(CONFIG_NFS_V4)
1055struct compat_nfs_string {
1056	compat_uint_t len;
1057	compat_uptr_t data;
1058};
1059
1060static inline void compat_nfs_string(struct nfs_string *dst,
1061				     struct compat_nfs_string *src)
1062{
1063	dst->data = compat_ptr(src->data);
1064	dst->len = src->len;
1065}
1066
1067struct compat_nfs4_mount_data_v1 {
1068	compat_int_t version;
1069	compat_int_t flags;
1070	compat_int_t rsize;
1071	compat_int_t wsize;
1072	compat_int_t timeo;
1073	compat_int_t retrans;
1074	compat_int_t acregmin;
1075	compat_int_t acregmax;
1076	compat_int_t acdirmin;
1077	compat_int_t acdirmax;
1078	struct compat_nfs_string client_addr;
1079	struct compat_nfs_string mnt_path;
1080	struct compat_nfs_string hostname;
1081	compat_uint_t host_addrlen;
1082	compat_uptr_t host_addr;
1083	compat_int_t proto;
1084	compat_int_t auth_flavourlen;
1085	compat_uptr_t auth_flavours;
1086};
1087
1088static void nfs4_compat_mount_data_conv(struct nfs4_mount_data *data)
1089{
1090	struct compat_nfs4_mount_data_v1 *compat =
1091			(struct compat_nfs4_mount_data_v1 *)data;
1092
1093	/* copy the fields backwards */
1094	data->auth_flavours = compat_ptr(compat->auth_flavours);
1095	data->auth_flavourlen = compat->auth_flavourlen;
1096	data->proto = compat->proto;
1097	data->host_addr = compat_ptr(compat->host_addr);
1098	data->host_addrlen = compat->host_addrlen;
1099	compat_nfs_string(&data->hostname, &compat->hostname);
1100	compat_nfs_string(&data->mnt_path, &compat->mnt_path);
1101	compat_nfs_string(&data->client_addr, &compat->client_addr);
1102	data->acdirmax = compat->acdirmax;
1103	data->acdirmin = compat->acdirmin;
1104	data->acregmax = compat->acregmax;
1105	data->acregmin = compat->acregmin;
1106	data->retrans = compat->retrans;
1107	data->timeo = compat->timeo;
1108	data->wsize = compat->wsize;
1109	data->rsize = compat->rsize;
1110	data->flags = compat->flags;
1111	data->version = compat->version;
1112}
1113
1114/*
1115 * Validate NFSv4 mount options
1116 */
1117static int nfs4_parse_monolithic(struct fs_context *fc,
1118				 struct nfs4_mount_data *data)
1119{
1120	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1121	struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
1122	char *c;
1123
1124	if (!data) {
1125		if (is_remount_fc(fc))
1126			goto done;
1127		return nfs_invalf(fc,
1128			"NFS4: mount program didn't pass any mount data");
1129	}
1130
1131	ctx->version = 4;
1132
1133	if (data->version != 1)
1134		return generic_parse_monolithic(fc, data);
1135
1136	if (in_compat_syscall())
1137		nfs4_compat_mount_data_conv(data);
1138
1139	if (data->host_addrlen > sizeof(ctx->nfs_server.address))
1140		goto out_no_address;
1141	if (data->host_addrlen == 0)
1142		goto out_no_address;
1143	ctx->nfs_server.addrlen = data->host_addrlen;
1144	if (copy_from_user(sap, data->host_addr, data->host_addrlen))
1145		return -EFAULT;
1146	if (!nfs_verify_server_address(sap))
1147		goto out_no_address;
1148	ctx->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
1149
1150	if (data->auth_flavourlen) {
1151		rpc_authflavor_t pseudoflavor;
1152
1153		if (data->auth_flavourlen > 1)
1154			goto out_inval_auth;
1155		if (copy_from_user(&pseudoflavor, data->auth_flavours,
1156				   sizeof(pseudoflavor)))
1157			return -EFAULT;
1158		ctx->selected_flavor = pseudoflavor;
1159	} else {
1160		ctx->selected_flavor = RPC_AUTH_UNIX;
1161	}
1162
1163	c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1164	if (IS_ERR(c))
1165		return PTR_ERR(c);
1166	ctx->nfs_server.hostname = c;
1167
1168	c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1169	if (IS_ERR(c))
1170		return PTR_ERR(c);
1171	ctx->nfs_server.export_path = c;
1172	dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", c);
1173
1174	c = strndup_user(data->client_addr.data, 16);
1175	if (IS_ERR(c))
1176		return PTR_ERR(c);
1177	ctx->client_address = c;
1178
1179	/*
1180	 * Translate to nfs_fs_context, which nfs_fill_super
1181	 * can deal with.
1182	 */
1183
1184	ctx->flags	= data->flags & NFS4_MOUNT_FLAGMASK;
1185	ctx->rsize	= data->rsize;
1186	ctx->wsize	= data->wsize;
1187	ctx->timeo	= data->timeo;
1188	ctx->retrans	= data->retrans;
1189	ctx->acregmin	= data->acregmin;
1190	ctx->acregmax	= data->acregmax;
1191	ctx->acdirmin	= data->acdirmin;
1192	ctx->acdirmax	= data->acdirmax;
1193	ctx->nfs_server.protocol = data->proto;
1194	nfs_validate_transport_protocol(ctx);
1195	if (ctx->nfs_server.protocol == XPRT_TRANSPORT_UDP)
1196		goto out_invalid_transport_udp;
1197done:
1198	ctx->skip_reconfig_option_check = true;
1199	return 0;
1200
1201out_inval_auth:
1202	return nfs_invalf(fc, "NFS4: Invalid number of RPC auth flavours %d",
1203		      data->auth_flavourlen);
1204
1205out_no_address:
1206	return nfs_invalf(fc, "NFS4: mount program didn't pass remote address");
1207
1208out_invalid_transport_udp:
1209	return nfs_invalf(fc, "NFS: Unsupported transport protocol udp");
1210}
1211#endif
1212
1213/*
1214 * Parse a monolithic block of data from sys_mount().
1215 */
1216static int nfs_fs_context_parse_monolithic(struct fs_context *fc,
1217					   void *data)
1218{
1219	if (fc->fs_type == &nfs_fs_type)
1220		return nfs23_parse_monolithic(fc, data);
1221
1222#if IS_ENABLED(CONFIG_NFS_V4)
1223	if (fc->fs_type == &nfs4_fs_type)
1224		return nfs4_parse_monolithic(fc, data);
1225#endif
1226
1227	return nfs_invalf(fc, "NFS: Unsupported monolithic data version");
1228}
1229
1230/*
1231 * Validate the preparsed information in the config.
1232 */
1233static int nfs_fs_context_validate(struct fs_context *fc)
1234{
1235	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1236	struct nfs_subversion *nfs_mod;
1237	struct sockaddr *sap = (struct sockaddr *)&ctx->nfs_server.address;
1238	int max_namelen = PAGE_SIZE;
1239	int max_pathlen = NFS_MAXPATHLEN;
1240	int port = 0;
1241	int ret;
1242
1243	if (!fc->source)
1244		goto out_no_device_name;
1245
1246	/* Check for sanity first. */
1247	if (ctx->minorversion && ctx->version != 4)
1248		goto out_minorversion_mismatch;
1249
1250	if (ctx->options & NFS_OPTION_MIGRATION &&
1251	    (ctx->version != 4 || ctx->minorversion != 0))
1252		goto out_migration_misuse;
1253
1254	/* Verify that any proto=/mountproto= options match the address
1255	 * families in the addr=/mountaddr= options.
1256	 */
1257	if (ctx->protofamily != AF_UNSPEC &&
1258	    ctx->protofamily != ctx->nfs_server.address.sa_family)
1259		goto out_proto_mismatch;
1260
1261	if (ctx->mountfamily != AF_UNSPEC) {
1262		if (ctx->mount_server.addrlen) {
1263			if (ctx->mountfamily != ctx->mount_server.address.sa_family)
1264				goto out_mountproto_mismatch;
1265		} else {
1266			if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
1267				goto out_mountproto_mismatch;
1268		}
1269	}
1270
1271	if (!nfs_verify_server_address(sap))
1272		goto out_no_address;
1273
1274	if (ctx->version == 4) {
1275		if (IS_ENABLED(CONFIG_NFS_V4)) {
1276			if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1277				port = NFS_RDMA_PORT;
1278			else
1279				port = NFS_PORT;
1280			max_namelen = NFS4_MAXNAMLEN;
1281			max_pathlen = NFS4_MAXPATHLEN;
1282			nfs_validate_transport_protocol(ctx);
1283			if (ctx->nfs_server.protocol == XPRT_TRANSPORT_UDP)
1284				goto out_invalid_transport_udp;
1285			ctx->flags &= ~(NFS_MOUNT_NONLM | NFS_MOUNT_NOACL |
1286					NFS_MOUNT_VER3 | NFS_MOUNT_LOCAL_FLOCK |
1287					NFS_MOUNT_LOCAL_FCNTL);
1288		} else {
1289			goto out_v4_not_compiled;
1290		}
1291	} else {
1292		nfs_set_mount_transport_protocol(ctx);
1293#ifdef CONFIG_NFS_DISABLE_UDP_SUPPORT
1294	       if (ctx->nfs_server.protocol == XPRT_TRANSPORT_UDP)
1295		       goto out_invalid_transport_udp;
1296#endif
1297		if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1298			port = NFS_RDMA_PORT;
1299	}
1300
1301	nfs_set_port(sap, &ctx->nfs_server.port, port);
1302
1303	ret = nfs_parse_source(fc, max_namelen, max_pathlen);
1304	if (ret < 0)
1305		return ret;
1306
1307	/* Load the NFS protocol module if we haven't done so yet */
1308	if (!ctx->nfs_mod) {
1309		nfs_mod = get_nfs_version(ctx->version);
1310		if (IS_ERR(nfs_mod)) {
1311			ret = PTR_ERR(nfs_mod);
1312			goto out_version_unavailable;
1313		}
1314		ctx->nfs_mod = nfs_mod;
1315	}
1316
1317	/* Ensure the filesystem context has the correct fs_type */
1318	if (fc->fs_type != ctx->nfs_mod->nfs_fs) {
1319		module_put(fc->fs_type->owner);
1320		__module_get(ctx->nfs_mod->nfs_fs->owner);
1321		fc->fs_type = ctx->nfs_mod->nfs_fs;
1322	}
1323	return 0;
1324
1325out_no_device_name:
1326	return nfs_invalf(fc, "NFS: Device name not specified");
1327out_v4_not_compiled:
1328	nfs_errorf(fc, "NFS: NFSv4 is not compiled into kernel");
1329	return -EPROTONOSUPPORT;
1330out_invalid_transport_udp:
1331	return nfs_invalf(fc, "NFS: Unsupported transport protocol udp");
1332out_no_address:
1333	return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1334out_mountproto_mismatch:
1335	return nfs_invalf(fc, "NFS: Mount server address does not match mountproto= option");
1336out_proto_mismatch:
1337	return nfs_invalf(fc, "NFS: Server address does not match proto= option");
1338out_minorversion_mismatch:
1339	return nfs_invalf(fc, "NFS: Mount option vers=%u does not support minorversion=%u",
1340			  ctx->version, ctx->minorversion);
1341out_migration_misuse:
1342	return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS version");
1343out_version_unavailable:
1344	nfs_errorf(fc, "NFS: Version unavailable");
1345	return ret;
1346}
1347
1348/*
1349 * Create an NFS superblock by the appropriate method.
1350 */
1351static int nfs_get_tree(struct fs_context *fc)
1352{
1353	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1354	int err = nfs_fs_context_validate(fc);
1355
1356	if (err)
1357		return err;
1358	if (!ctx->internal)
1359		return ctx->nfs_mod->rpc_ops->try_get_tree(fc);
1360	else
1361		return nfs_get_tree_common(fc);
1362}
1363
1364/*
1365 * Handle duplication of a configuration.  The caller copied *src into *sc, but
1366 * it can't deal with resource pointers in the filesystem context, so we have
1367 * to do that.  We need to clear pointers, copy data or get extra refs as
1368 * appropriate.
1369 */
1370static int nfs_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1371{
1372	struct nfs_fs_context *src = nfs_fc2context(src_fc), *ctx;
1373
1374	ctx = kmemdup(src, sizeof(struct nfs_fs_context), GFP_KERNEL);
1375	if (!ctx)
1376		return -ENOMEM;
1377
1378	ctx->mntfh = nfs_alloc_fhandle();
1379	if (!ctx->mntfh) {
1380		kfree(ctx);
1381		return -ENOMEM;
1382	}
1383	nfs_copy_fh(ctx->mntfh, src->mntfh);
1384
1385	__module_get(ctx->nfs_mod->owner);
1386	ctx->client_address		= NULL;
1387	ctx->mount_server.hostname	= NULL;
1388	ctx->nfs_server.export_path	= NULL;
1389	ctx->nfs_server.hostname	= NULL;
1390	ctx->fscache_uniq		= NULL;
1391	ctx->clone_data.fattr		= NULL;
1392	fc->fs_private = ctx;
1393	return 0;
1394}
1395
1396static void nfs_fs_context_free(struct fs_context *fc)
1397{
1398	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1399
1400	if (ctx) {
1401		if (ctx->server)
1402			nfs_free_server(ctx->server);
1403		if (ctx->nfs_mod)
1404			put_nfs_version(ctx->nfs_mod);
1405		kfree(ctx->client_address);
1406		kfree(ctx->mount_server.hostname);
1407		kfree(ctx->nfs_server.export_path);
1408		kfree(ctx->nfs_server.hostname);
1409		kfree(ctx->fscache_uniq);
1410		nfs_free_fhandle(ctx->mntfh);
1411		nfs_free_fattr(ctx->clone_data.fattr);
1412		kfree(ctx);
1413	}
1414}
1415
1416static const struct fs_context_operations nfs_fs_context_ops = {
1417	.free			= nfs_fs_context_free,
1418	.dup			= nfs_fs_context_dup,
1419	.parse_param		= nfs_fs_context_parse_param,
1420	.parse_monolithic	= nfs_fs_context_parse_monolithic,
1421	.get_tree		= nfs_get_tree,
1422	.reconfigure		= nfs_reconfigure,
1423};
1424
1425/*
1426 * Prepare superblock configuration.  We use the namespaces attached to the
1427 * context.  This may be the current process's namespaces, or it may be a
1428 * container's namespaces.
1429 */
1430static int nfs_init_fs_context(struct fs_context *fc)
1431{
1432	struct nfs_fs_context *ctx;
1433
1434	ctx = kzalloc(sizeof(struct nfs_fs_context), GFP_KERNEL);
1435	if (unlikely(!ctx))
1436		return -ENOMEM;
1437
1438	ctx->mntfh = nfs_alloc_fhandle();
1439	if (unlikely(!ctx->mntfh)) {
1440		kfree(ctx);
1441		return -ENOMEM;
1442	}
1443
1444	ctx->protofamily	= AF_UNSPEC;
1445	ctx->mountfamily	= AF_UNSPEC;
1446	ctx->mount_server.port	= NFS_UNSPEC_PORT;
1447
1448	if (fc->root) {
1449		/* reconfigure, start with the current config */
1450		struct nfs_server *nfss = fc->root->d_sb->s_fs_info;
1451		struct net *net = nfss->nfs_client->cl_net;
1452
1453		ctx->flags		= nfss->flags;
1454		ctx->rsize		= nfss->rsize;
1455		ctx->wsize		= nfss->wsize;
1456		ctx->retrans		= nfss->client->cl_timeout->to_retries;
1457		ctx->selected_flavor	= nfss->client->cl_auth->au_flavor;
1458		ctx->acregmin		= nfss->acregmin / HZ;
1459		ctx->acregmax		= nfss->acregmax / HZ;
1460		ctx->acdirmin		= nfss->acdirmin / HZ;
1461		ctx->acdirmax		= nfss->acdirmax / HZ;
1462		ctx->timeo		= 10U * nfss->client->cl_timeout->to_initval / HZ;
1463		ctx->nfs_server.port	= nfss->port;
1464		ctx->nfs_server.addrlen	= nfss->nfs_client->cl_addrlen;
1465		ctx->version		= nfss->nfs_client->rpc_ops->version;
1466		ctx->minorversion	= nfss->nfs_client->cl_minorversion;
1467
1468		memcpy(&ctx->nfs_server.address, &nfss->nfs_client->cl_addr,
1469			ctx->nfs_server.addrlen);
1470
1471		if (fc->net_ns != net) {
1472			put_net(fc->net_ns);
1473			fc->net_ns = get_net(net);
1474		}
1475
1476		ctx->nfs_mod = nfss->nfs_client->cl_nfs_mod;
1477		__module_get(ctx->nfs_mod->owner);
1478	} else {
1479		/* defaults */
1480		ctx->timeo		= NFS_UNSPEC_TIMEO;
1481		ctx->retrans		= NFS_UNSPEC_RETRANS;
1482		ctx->acregmin		= NFS_DEF_ACREGMIN;
1483		ctx->acregmax		= NFS_DEF_ACREGMAX;
1484		ctx->acdirmin		= NFS_DEF_ACDIRMIN;
1485		ctx->acdirmax		= NFS_DEF_ACDIRMAX;
1486		ctx->nfs_server.port	= NFS_UNSPEC_PORT;
1487		ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1488		ctx->selected_flavor	= RPC_AUTH_MAXFLAVOR;
1489		ctx->minorversion	= 0;
1490		ctx->need_mount		= true;
1491	}
1492	fc->fs_private = ctx;
1493	fc->ops = &nfs_fs_context_ops;
1494	return 0;
1495}
1496
1497struct file_system_type nfs_fs_type = {
1498	.owner			= THIS_MODULE,
1499	.name			= "nfs",
1500	.init_fs_context	= nfs_init_fs_context,
1501	.parameters		= nfs_fs_parameters,
1502	.kill_sb		= nfs_kill_super,
1503	.fs_flags		= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1504};
1505MODULE_ALIAS_FS("nfs");
1506EXPORT_SYMBOL_GPL(nfs_fs_type);
1507
1508#if IS_ENABLED(CONFIG_NFS_V4)
1509struct file_system_type nfs4_fs_type = {
1510	.owner			= THIS_MODULE,
1511	.name			= "nfs4",
1512	.init_fs_context	= nfs_init_fs_context,
1513	.parameters		= nfs_fs_parameters,
1514	.kill_sb		= nfs_kill_super,
1515	.fs_flags		= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1516};
1517MODULE_ALIAS_FS("nfs4");
1518MODULE_ALIAS("nfs4");
1519EXPORT_SYMBOL_GPL(nfs4_fs_type);
1520#endif /* CONFIG_NFS_V4 */
1521