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/compat.h>
14#include <linux/module.h>
15#include <linux/fs.h>
16#include <linux/fs_context.h>
17#include <linux/fs_parser.h>
18#include <linux/nfs_fs.h>
19#include <linux/nfs_mount.h>
20#include <linux/nfs4_mount.h>
21
22#include <net/handshake.h>
23
24#include "nfs.h"
25#include "internal.h"
26
27#include "nfstrace.h"
28
29#define NFSDBG_FACILITY		NFSDBG_MOUNT
30
31#if IS_ENABLED(CONFIG_NFS_V3)
32#define NFS_DEFAULT_VERSION 3
33#else
34#define NFS_DEFAULT_VERSION 2
35#endif
36
37#define NFS_MAX_CONNECTIONS 16
38
39enum nfs_param {
40	Opt_ac,
41	Opt_acdirmax,
42	Opt_acdirmin,
43	Opt_acl,
44	Opt_acregmax,
45	Opt_acregmin,
46	Opt_actimeo,
47	Opt_addr,
48	Opt_bg,
49	Opt_bsize,
50	Opt_clientaddr,
51	Opt_cto,
52	Opt_fg,
53	Opt_fscache,
54	Opt_fscache_flag,
55	Opt_hard,
56	Opt_intr,
57	Opt_local_lock,
58	Opt_lock,
59	Opt_lookupcache,
60	Opt_migration,
61	Opt_minorversion,
62	Opt_mountaddr,
63	Opt_mounthost,
64	Opt_mountport,
65	Opt_mountproto,
66	Opt_mountvers,
67	Opt_namelen,
68	Opt_nconnect,
69	Opt_max_connect,
70	Opt_port,
71	Opt_posix,
72	Opt_proto,
73	Opt_rdirplus,
74	Opt_rdma,
75	Opt_resvport,
76	Opt_retrans,
77	Opt_retry,
78	Opt_rsize,
79	Opt_sec,
80	Opt_sharecache,
81	Opt_sloppy,
82	Opt_soft,
83	Opt_softerr,
84	Opt_softreval,
85	Opt_source,
86	Opt_tcp,
87	Opt_timeo,
88	Opt_trunkdiscovery,
89	Opt_udp,
90	Opt_v,
91	Opt_vers,
92	Opt_wsize,
93	Opt_write,
94	Opt_xprtsec,
95};
96
97enum {
98	Opt_local_lock_all,
99	Opt_local_lock_flock,
100	Opt_local_lock_none,
101	Opt_local_lock_posix,
102};
103
104static const struct constant_table nfs_param_enums_local_lock[] = {
105	{ "all",		Opt_local_lock_all },
106	{ "flock",	Opt_local_lock_flock },
107	{ "posix",	Opt_local_lock_posix },
108	{ "none",		Opt_local_lock_none },
109	{}
110};
111
112enum {
113	Opt_lookupcache_all,
114	Opt_lookupcache_none,
115	Opt_lookupcache_positive,
116};
117
118static const struct constant_table nfs_param_enums_lookupcache[] = {
119	{ "all",		Opt_lookupcache_all },
120	{ "none",		Opt_lookupcache_none },
121	{ "pos",		Opt_lookupcache_positive },
122	{ "positive",		Opt_lookupcache_positive },
123	{}
124};
125
126enum {
127	Opt_write_lazy,
128	Opt_write_eager,
129	Opt_write_wait,
130};
131
132static const struct constant_table nfs_param_enums_write[] = {
133	{ "lazy",		Opt_write_lazy },
134	{ "eager",		Opt_write_eager },
135	{ "wait",		Opt_write_wait },
136	{}
137};
138
139static const struct fs_parameter_spec nfs_fs_parameters[] = {
140	fsparam_flag_no("ac",		Opt_ac),
141	fsparam_u32   ("acdirmax",	Opt_acdirmax),
142	fsparam_u32   ("acdirmin",	Opt_acdirmin),
143	fsparam_flag_no("acl",		Opt_acl),
144	fsparam_u32   ("acregmax",	Opt_acregmax),
145	fsparam_u32   ("acregmin",	Opt_acregmin),
146	fsparam_u32   ("actimeo",	Opt_actimeo),
147	fsparam_string("addr",		Opt_addr),
148	fsparam_flag  ("bg",		Opt_bg),
149	fsparam_u32   ("bsize",		Opt_bsize),
150	fsparam_string("clientaddr",	Opt_clientaddr),
151	fsparam_flag_no("cto",		Opt_cto),
152	fsparam_flag  ("fg",		Opt_fg),
153	fsparam_flag_no("fsc",		Opt_fscache_flag),
154	fsparam_string("fsc",		Opt_fscache),
155	fsparam_flag  ("hard",		Opt_hard),
156	__fsparam(NULL, "intr",		Opt_intr,
157		  fs_param_neg_with_no|fs_param_deprecated, NULL),
158	fsparam_enum  ("local_lock",	Opt_local_lock, nfs_param_enums_local_lock),
159	fsparam_flag_no("lock",		Opt_lock),
160	fsparam_enum  ("lookupcache",	Opt_lookupcache, nfs_param_enums_lookupcache),
161	fsparam_flag_no("migration",	Opt_migration),
162	fsparam_u32   ("minorversion",	Opt_minorversion),
163	fsparam_string("mountaddr",	Opt_mountaddr),
164	fsparam_string("mounthost",	Opt_mounthost),
165	fsparam_u32   ("mountport",	Opt_mountport),
166	fsparam_string("mountproto",	Opt_mountproto),
167	fsparam_u32   ("mountvers",	Opt_mountvers),
168	fsparam_u32   ("namlen",	Opt_namelen),
169	fsparam_u32   ("nconnect",	Opt_nconnect),
170	fsparam_u32   ("max_connect",	Opt_max_connect),
171	fsparam_string("nfsvers",	Opt_vers),
172	fsparam_u32   ("port",		Opt_port),
173	fsparam_flag_no("posix",	Opt_posix),
174	fsparam_string("proto",		Opt_proto),
175	fsparam_flag_no("rdirplus",	Opt_rdirplus),
176	fsparam_flag  ("rdma",		Opt_rdma),
177	fsparam_flag_no("resvport",	Opt_resvport),
178	fsparam_u32   ("retrans",	Opt_retrans),
179	fsparam_string("retry",		Opt_retry),
180	fsparam_u32   ("rsize",		Opt_rsize),
181	fsparam_string("sec",		Opt_sec),
182	fsparam_flag_no("sharecache",	Opt_sharecache),
183	fsparam_flag  ("sloppy",	Opt_sloppy),
184	fsparam_flag  ("soft",		Opt_soft),
185	fsparam_flag  ("softerr",	Opt_softerr),
186	fsparam_flag  ("softreval",	Opt_softreval),
187	fsparam_string("source",	Opt_source),
188	fsparam_flag  ("tcp",		Opt_tcp),
189	fsparam_u32   ("timeo",		Opt_timeo),
190	fsparam_flag_no("trunkdiscovery", Opt_trunkdiscovery),
191	fsparam_flag  ("udp",		Opt_udp),
192	fsparam_flag  ("v2",		Opt_v),
193	fsparam_flag  ("v3",		Opt_v),
194	fsparam_flag  ("v4",		Opt_v),
195	fsparam_flag  ("v4.0",		Opt_v),
196	fsparam_flag  ("v4.1",		Opt_v),
197	fsparam_flag  ("v4.2",		Opt_v),
198	fsparam_string("vers",		Opt_vers),
199	fsparam_enum  ("write",		Opt_write, nfs_param_enums_write),
200	fsparam_u32   ("wsize",		Opt_wsize),
201	fsparam_string("xprtsec",	Opt_xprtsec),
202	{}
203};
204
205enum {
206	Opt_vers_2,
207	Opt_vers_3,
208	Opt_vers_4,
209	Opt_vers_4_0,
210	Opt_vers_4_1,
211	Opt_vers_4_2,
212};
213
214static const struct constant_table nfs_vers_tokens[] = {
215	{ "2",		Opt_vers_2 },
216	{ "3",		Opt_vers_3 },
217	{ "4",		Opt_vers_4 },
218	{ "4.0",	Opt_vers_4_0 },
219	{ "4.1",	Opt_vers_4_1 },
220	{ "4.2",	Opt_vers_4_2 },
221	{}
222};
223
224enum {
225	Opt_xprt_rdma,
226	Opt_xprt_rdma6,
227	Opt_xprt_tcp,
228	Opt_xprt_tcp6,
229	Opt_xprt_udp,
230	Opt_xprt_udp6,
231	nr__Opt_xprt
232};
233
234static const struct constant_table nfs_xprt_protocol_tokens[] = {
235	{ "rdma",	Opt_xprt_rdma },
236	{ "rdma6",	Opt_xprt_rdma6 },
237	{ "tcp",	Opt_xprt_tcp },
238	{ "tcp6",	Opt_xprt_tcp6 },
239	{ "udp",	Opt_xprt_udp },
240	{ "udp6",	Opt_xprt_udp6 },
241	{}
242};
243
244enum {
245	Opt_sec_krb5,
246	Opt_sec_krb5i,
247	Opt_sec_krb5p,
248	Opt_sec_lkey,
249	Opt_sec_lkeyi,
250	Opt_sec_lkeyp,
251	Opt_sec_none,
252	Opt_sec_spkm,
253	Opt_sec_spkmi,
254	Opt_sec_spkmp,
255	Opt_sec_sys,
256	nr__Opt_sec
257};
258
259static const struct constant_table nfs_secflavor_tokens[] = {
260	{ "krb5",	Opt_sec_krb5 },
261	{ "krb5i",	Opt_sec_krb5i },
262	{ "krb5p",	Opt_sec_krb5p },
263	{ "lkey",	Opt_sec_lkey },
264	{ "lkeyi",	Opt_sec_lkeyi },
265	{ "lkeyp",	Opt_sec_lkeyp },
266	{ "none",	Opt_sec_none },
267	{ "null",	Opt_sec_none },
268	{ "spkm3",	Opt_sec_spkm },
269	{ "spkm3i",	Opt_sec_spkmi },
270	{ "spkm3p",	Opt_sec_spkmp },
271	{ "sys",	Opt_sec_sys },
272	{}
273};
274
275enum {
276	Opt_xprtsec_none,
277	Opt_xprtsec_tls,
278	Opt_xprtsec_mtls,
279	nr__Opt_xprtsec
280};
281
282static const struct constant_table nfs_xprtsec_policies[] = {
283	{ "none",	Opt_xprtsec_none },
284	{ "tls",	Opt_xprtsec_tls },
285	{ "mtls",	Opt_xprtsec_mtls },
286	{}
287};
288
289/*
290 * Sanity-check a server address provided by the mount command.
291 *
292 * Address family must be initialized, and address must not be
293 * the ANY address for that family.
294 */
295static int nfs_verify_server_address(struct sockaddr_storage *addr)
296{
297	switch (addr->ss_family) {
298	case AF_INET: {
299		struct sockaddr_in *sa = (struct sockaddr_in *)addr;
300		return sa->sin_addr.s_addr != htonl(INADDR_ANY);
301	}
302	case AF_INET6: {
303		struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
304		return !ipv6_addr_any(sa);
305	}
306	}
307
308	return 0;
309}
310
311#ifdef CONFIG_NFS_DISABLE_UDP_SUPPORT
312static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
313{
314	return true;
315}
316#else
317static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
318{
319	if (ctx->version == 4)
320		return true;
321	return false;
322}
323#endif
324
325/*
326 * Sanity check the NFS transport protocol.
327 */
328static int nfs_validate_transport_protocol(struct fs_context *fc,
329					   struct nfs_fs_context *ctx)
330{
331	switch (ctx->nfs_server.protocol) {
332	case XPRT_TRANSPORT_UDP:
333		if (nfs_server_transport_udp_invalid(ctx))
334			goto out_invalid_transport_udp;
335		break;
336	case XPRT_TRANSPORT_TCP:
337	case XPRT_TRANSPORT_RDMA:
338		break;
339	default:
340		ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
341	}
342
343	if (ctx->xprtsec.policy != RPC_XPRTSEC_NONE)
344		switch (ctx->nfs_server.protocol) {
345		case XPRT_TRANSPORT_TCP:
346			ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP_TLS;
347			break;
348		default:
349			goto out_invalid_xprtsec_policy;
350	}
351
352	return 0;
353out_invalid_transport_udp:
354	return nfs_invalf(fc, "NFS: Unsupported transport protocol udp");
355out_invalid_xprtsec_policy:
356	return nfs_invalf(fc, "NFS: Transport does not support xprtsec");
357}
358
359/*
360 * For text based NFSv2/v3 mounts, the mount protocol transport default
361 * settings should depend upon the specified NFS transport.
362 */
363static void nfs_set_mount_transport_protocol(struct nfs_fs_context *ctx)
364{
365	if (ctx->mount_server.protocol == XPRT_TRANSPORT_UDP ||
366	    ctx->mount_server.protocol == XPRT_TRANSPORT_TCP)
367			return;
368	switch (ctx->nfs_server.protocol) {
369	case XPRT_TRANSPORT_UDP:
370		ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
371		break;
372	case XPRT_TRANSPORT_TCP:
373	case XPRT_TRANSPORT_RDMA:
374		ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
375	}
376}
377
378/*
379 * Add 'flavor' to 'auth_info' if not already present.
380 * Returns true if 'flavor' ends up in the list, false otherwise
381 */
382static int nfs_auth_info_add(struct fs_context *fc,
383			     struct nfs_auth_info *auth_info,
384			     rpc_authflavor_t flavor)
385{
386	unsigned int i;
387	unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
388
389	/* make sure this flavor isn't already in the list */
390	for (i = 0; i < auth_info->flavor_len; i++) {
391		if (flavor == auth_info->flavors[i])
392			return 0;
393	}
394
395	if (auth_info->flavor_len + 1 >= max_flavor_len)
396		return nfs_invalf(fc, "NFS: too many sec= flavors");
397
398	auth_info->flavors[auth_info->flavor_len++] = flavor;
399	return 0;
400}
401
402/*
403 * Parse the value of the 'sec=' option.
404 */
405static int nfs_parse_security_flavors(struct fs_context *fc,
406				      struct fs_parameter *param)
407{
408	struct nfs_fs_context *ctx = nfs_fc2context(fc);
409	rpc_authflavor_t pseudoflavor;
410	char *string = param->string, *p;
411	int ret;
412
413	trace_nfs_mount_assign(param->key, string);
414
415	while ((p = strsep(&string, ":")) != NULL) {
416		if (!*p)
417			continue;
418		switch (lookup_constant(nfs_secflavor_tokens, p, -1)) {
419		case Opt_sec_none:
420			pseudoflavor = RPC_AUTH_NULL;
421			break;
422		case Opt_sec_sys:
423			pseudoflavor = RPC_AUTH_UNIX;
424			break;
425		case Opt_sec_krb5:
426			pseudoflavor = RPC_AUTH_GSS_KRB5;
427			break;
428		case Opt_sec_krb5i:
429			pseudoflavor = RPC_AUTH_GSS_KRB5I;
430			break;
431		case Opt_sec_krb5p:
432			pseudoflavor = RPC_AUTH_GSS_KRB5P;
433			break;
434		case Opt_sec_lkey:
435			pseudoflavor = RPC_AUTH_GSS_LKEY;
436			break;
437		case Opt_sec_lkeyi:
438			pseudoflavor = RPC_AUTH_GSS_LKEYI;
439			break;
440		case Opt_sec_lkeyp:
441			pseudoflavor = RPC_AUTH_GSS_LKEYP;
442			break;
443		case Opt_sec_spkm:
444			pseudoflavor = RPC_AUTH_GSS_SPKM;
445			break;
446		case Opt_sec_spkmi:
447			pseudoflavor = RPC_AUTH_GSS_SPKMI;
448			break;
449		case Opt_sec_spkmp:
450			pseudoflavor = RPC_AUTH_GSS_SPKMP;
451			break;
452		default:
453			return nfs_invalf(fc, "NFS: sec=%s option not recognized", p);
454		}
455
456		ret = nfs_auth_info_add(fc, &ctx->auth_info, pseudoflavor);
457		if (ret < 0)
458			return ret;
459	}
460
461	return 0;
462}
463
464static int nfs_parse_xprtsec_policy(struct fs_context *fc,
465				    struct fs_parameter *param)
466{
467	struct nfs_fs_context *ctx = nfs_fc2context(fc);
468
469	trace_nfs_mount_assign(param->key, param->string);
470
471	switch (lookup_constant(nfs_xprtsec_policies, param->string, -1)) {
472	case Opt_xprtsec_none:
473		ctx->xprtsec.policy = RPC_XPRTSEC_NONE;
474		break;
475	case Opt_xprtsec_tls:
476		ctx->xprtsec.policy = RPC_XPRTSEC_TLS_ANON;
477		break;
478	case Opt_xprtsec_mtls:
479		ctx->xprtsec.policy = RPC_XPRTSEC_TLS_X509;
480		break;
481	default:
482		return nfs_invalf(fc, "NFS: Unrecognized transport security policy");
483	}
484	return 0;
485}
486
487static int nfs_parse_version_string(struct fs_context *fc,
488				    const char *string)
489{
490	struct nfs_fs_context *ctx = nfs_fc2context(fc);
491
492	ctx->flags &= ~NFS_MOUNT_VER3;
493	switch (lookup_constant(nfs_vers_tokens, string, -1)) {
494	case Opt_vers_2:
495		ctx->version = 2;
496		break;
497	case Opt_vers_3:
498		ctx->flags |= NFS_MOUNT_VER3;
499		ctx->version = 3;
500		break;
501	case Opt_vers_4:
502		/* Backward compatibility option. In future,
503		 * the mount program should always supply
504		 * a NFSv4 minor version number.
505		 */
506		ctx->version = 4;
507		break;
508	case Opt_vers_4_0:
509		ctx->version = 4;
510		ctx->minorversion = 0;
511		break;
512	case Opt_vers_4_1:
513		ctx->version = 4;
514		ctx->minorversion = 1;
515		break;
516	case Opt_vers_4_2:
517		ctx->version = 4;
518		ctx->minorversion = 2;
519		break;
520	default:
521		return nfs_invalf(fc, "NFS: Unsupported NFS version");
522	}
523	return 0;
524}
525
526/*
527 * Parse a single mount parameter.
528 */
529static int nfs_fs_context_parse_param(struct fs_context *fc,
530				      struct fs_parameter *param)
531{
532	struct fs_parse_result result;
533	struct nfs_fs_context *ctx = nfs_fc2context(fc);
534	unsigned short protofamily, mountfamily;
535	unsigned int len;
536	int ret, opt;
537
538	trace_nfs_mount_option(param);
539
540	opt = fs_parse(fc, nfs_fs_parameters, param, &result);
541	if (opt < 0)
542		return (opt == -ENOPARAM && ctx->sloppy) ? 1 : opt;
543
544	if (fc->security)
545		ctx->has_sec_mnt_opts = 1;
546
547	switch (opt) {
548	case Opt_source:
549		if (fc->source)
550			return nfs_invalf(fc, "NFS: Multiple sources not supported");
551		fc->source = param->string;
552		param->string = NULL;
553		break;
554
555		/*
556		 * boolean options:  foo/nofoo
557		 */
558	case Opt_soft:
559		ctx->flags |= NFS_MOUNT_SOFT;
560		ctx->flags &= ~NFS_MOUNT_SOFTERR;
561		break;
562	case Opt_softerr:
563		ctx->flags |= NFS_MOUNT_SOFTERR | NFS_MOUNT_SOFTREVAL;
564		ctx->flags &= ~NFS_MOUNT_SOFT;
565		break;
566	case Opt_hard:
567		ctx->flags &= ~(NFS_MOUNT_SOFT |
568				NFS_MOUNT_SOFTERR |
569				NFS_MOUNT_SOFTREVAL);
570		break;
571	case Opt_softreval:
572		if (result.negated)
573			ctx->flags &= ~NFS_MOUNT_SOFTREVAL;
574		else
575			ctx->flags |= NFS_MOUNT_SOFTREVAL;
576		break;
577	case Opt_posix:
578		if (result.negated)
579			ctx->flags &= ~NFS_MOUNT_POSIX;
580		else
581			ctx->flags |= NFS_MOUNT_POSIX;
582		break;
583	case Opt_cto:
584		if (result.negated)
585			ctx->flags |= NFS_MOUNT_NOCTO;
586		else
587			ctx->flags &= ~NFS_MOUNT_NOCTO;
588		break;
589	case Opt_trunkdiscovery:
590		if (result.negated)
591			ctx->flags &= ~NFS_MOUNT_TRUNK_DISCOVERY;
592		else
593			ctx->flags |= NFS_MOUNT_TRUNK_DISCOVERY;
594		break;
595	case Opt_ac:
596		if (result.negated)
597			ctx->flags |= NFS_MOUNT_NOAC;
598		else
599			ctx->flags &= ~NFS_MOUNT_NOAC;
600		break;
601	case Opt_lock:
602		if (result.negated) {
603			ctx->flags |= NFS_MOUNT_NONLM;
604			ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
605		} else {
606			ctx->flags &= ~NFS_MOUNT_NONLM;
607			ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
608		}
609		break;
610	case Opt_udp:
611		ctx->flags &= ~NFS_MOUNT_TCP;
612		ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
613		break;
614	case Opt_tcp:
615	case Opt_rdma:
616		ctx->flags |= NFS_MOUNT_TCP; /* for side protocols */
617		ret = xprt_find_transport_ident(param->key);
618		if (ret < 0)
619			goto out_bad_transport;
620		ctx->nfs_server.protocol = ret;
621		break;
622	case Opt_acl:
623		if (result.negated)
624			ctx->flags |= NFS_MOUNT_NOACL;
625		else
626			ctx->flags &= ~NFS_MOUNT_NOACL;
627		break;
628	case Opt_rdirplus:
629		if (result.negated)
630			ctx->flags |= NFS_MOUNT_NORDIRPLUS;
631		else
632			ctx->flags &= ~NFS_MOUNT_NORDIRPLUS;
633		break;
634	case Opt_sharecache:
635		if (result.negated)
636			ctx->flags |= NFS_MOUNT_UNSHARED;
637		else
638			ctx->flags &= ~NFS_MOUNT_UNSHARED;
639		break;
640	case Opt_resvport:
641		if (result.negated)
642			ctx->flags |= NFS_MOUNT_NORESVPORT;
643		else
644			ctx->flags &= ~NFS_MOUNT_NORESVPORT;
645		break;
646	case Opt_fscache_flag:
647		if (result.negated)
648			ctx->options &= ~NFS_OPTION_FSCACHE;
649		else
650			ctx->options |= NFS_OPTION_FSCACHE;
651		kfree(ctx->fscache_uniq);
652		ctx->fscache_uniq = NULL;
653		break;
654	case Opt_fscache:
655		trace_nfs_mount_assign(param->key, param->string);
656		ctx->options |= NFS_OPTION_FSCACHE;
657		kfree(ctx->fscache_uniq);
658		ctx->fscache_uniq = param->string;
659		param->string = NULL;
660		break;
661	case Opt_migration:
662		if (result.negated)
663			ctx->options &= ~NFS_OPTION_MIGRATION;
664		else
665			ctx->options |= NFS_OPTION_MIGRATION;
666		break;
667
668		/*
669		 * options that take numeric values
670		 */
671	case Opt_port:
672		if (result.uint_32 > USHRT_MAX)
673			goto out_of_bounds;
674		ctx->nfs_server.port = result.uint_32;
675		break;
676	case Opt_rsize:
677		ctx->rsize = result.uint_32;
678		break;
679	case Opt_wsize:
680		ctx->wsize = result.uint_32;
681		break;
682	case Opt_bsize:
683		ctx->bsize = result.uint_32;
684		break;
685	case Opt_timeo:
686		if (result.uint_32 < 1 || result.uint_32 > INT_MAX)
687			goto out_of_bounds;
688		ctx->timeo = result.uint_32;
689		break;
690	case Opt_retrans:
691		if (result.uint_32 > INT_MAX)
692			goto out_of_bounds;
693		ctx->retrans = result.uint_32;
694		break;
695	case Opt_acregmin:
696		ctx->acregmin = result.uint_32;
697		break;
698	case Opt_acregmax:
699		ctx->acregmax = result.uint_32;
700		break;
701	case Opt_acdirmin:
702		ctx->acdirmin = result.uint_32;
703		break;
704	case Opt_acdirmax:
705		ctx->acdirmax = result.uint_32;
706		break;
707	case Opt_actimeo:
708		ctx->acregmin = result.uint_32;
709		ctx->acregmax = result.uint_32;
710		ctx->acdirmin = result.uint_32;
711		ctx->acdirmax = result.uint_32;
712		break;
713	case Opt_namelen:
714		ctx->namlen = result.uint_32;
715		break;
716	case Opt_mountport:
717		if (result.uint_32 > USHRT_MAX)
718			goto out_of_bounds;
719		ctx->mount_server.port = result.uint_32;
720		break;
721	case Opt_mountvers:
722		if (result.uint_32 < NFS_MNT_VERSION ||
723		    result.uint_32 > NFS_MNT3_VERSION)
724			goto out_of_bounds;
725		ctx->mount_server.version = result.uint_32;
726		break;
727	case Opt_minorversion:
728		if (result.uint_32 > NFS4_MAX_MINOR_VERSION)
729			goto out_of_bounds;
730		ctx->minorversion = result.uint_32;
731		break;
732
733		/*
734		 * options that take text values
735		 */
736	case Opt_v:
737		ret = nfs_parse_version_string(fc, param->key + 1);
738		if (ret < 0)
739			return ret;
740		break;
741	case Opt_vers:
742		if (!param->string)
743			goto out_invalid_value;
744		trace_nfs_mount_assign(param->key, param->string);
745		ret = nfs_parse_version_string(fc, param->string);
746		if (ret < 0)
747			return ret;
748		break;
749	case Opt_sec:
750		ret = nfs_parse_security_flavors(fc, param);
751		if (ret < 0)
752			return ret;
753		break;
754	case Opt_xprtsec:
755		ret = nfs_parse_xprtsec_policy(fc, param);
756		if (ret < 0)
757			return ret;
758		break;
759
760	case Opt_proto:
761		if (!param->string)
762			goto out_invalid_value;
763		trace_nfs_mount_assign(param->key, param->string);
764		protofamily = AF_INET;
765		switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
766		case Opt_xprt_udp6:
767			protofamily = AF_INET6;
768			fallthrough;
769		case Opt_xprt_udp:
770			ctx->flags &= ~NFS_MOUNT_TCP;
771			ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
772			break;
773		case Opt_xprt_tcp6:
774			protofamily = AF_INET6;
775			fallthrough;
776		case Opt_xprt_tcp:
777			ctx->flags |= NFS_MOUNT_TCP;
778			ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
779			break;
780		case Opt_xprt_rdma6:
781			protofamily = AF_INET6;
782			fallthrough;
783		case Opt_xprt_rdma:
784			/* vector side protocols to TCP */
785			ctx->flags |= NFS_MOUNT_TCP;
786			ret = xprt_find_transport_ident(param->string);
787			if (ret < 0)
788				goto out_bad_transport;
789			ctx->nfs_server.protocol = ret;
790			break;
791		default:
792			goto out_bad_transport;
793		}
794
795		ctx->protofamily = protofamily;
796		break;
797
798	case Opt_mountproto:
799		if (!param->string)
800			goto out_invalid_value;
801		trace_nfs_mount_assign(param->key, param->string);
802		mountfamily = AF_INET;
803		switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
804		case Opt_xprt_udp6:
805			mountfamily = AF_INET6;
806			fallthrough;
807		case Opt_xprt_udp:
808			ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
809			break;
810		case Opt_xprt_tcp6:
811			mountfamily = AF_INET6;
812			fallthrough;
813		case Opt_xprt_tcp:
814			ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
815			break;
816		case Opt_xprt_rdma: /* not used for side protocols */
817		default:
818			goto out_bad_transport;
819		}
820		ctx->mountfamily = mountfamily;
821		break;
822
823	case Opt_addr:
824		trace_nfs_mount_assign(param->key, param->string);
825		len = rpc_pton(fc->net_ns, param->string, param->size,
826			       &ctx->nfs_server.address,
827			       sizeof(ctx->nfs_server._address));
828		if (len == 0)
829			goto out_invalid_address;
830		ctx->nfs_server.addrlen = len;
831		break;
832	case Opt_clientaddr:
833		trace_nfs_mount_assign(param->key, param->string);
834		kfree(ctx->client_address);
835		ctx->client_address = param->string;
836		param->string = NULL;
837		break;
838	case Opt_mounthost:
839		trace_nfs_mount_assign(param->key, param->string);
840		kfree(ctx->mount_server.hostname);
841		ctx->mount_server.hostname = param->string;
842		param->string = NULL;
843		break;
844	case Opt_mountaddr:
845		trace_nfs_mount_assign(param->key, param->string);
846		len = rpc_pton(fc->net_ns, param->string, param->size,
847			       &ctx->mount_server.address,
848			       sizeof(ctx->mount_server._address));
849		if (len == 0)
850			goto out_invalid_address;
851		ctx->mount_server.addrlen = len;
852		break;
853	case Opt_nconnect:
854		trace_nfs_mount_assign(param->key, param->string);
855		if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_CONNECTIONS)
856			goto out_of_bounds;
857		ctx->nfs_server.nconnect = result.uint_32;
858		break;
859	case Opt_max_connect:
860		trace_nfs_mount_assign(param->key, param->string);
861		if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_TRANSPORTS)
862			goto out_of_bounds;
863		ctx->nfs_server.max_connect = result.uint_32;
864		break;
865	case Opt_lookupcache:
866		trace_nfs_mount_assign(param->key, param->string);
867		switch (result.uint_32) {
868		case Opt_lookupcache_all:
869			ctx->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
870			break;
871		case Opt_lookupcache_positive:
872			ctx->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
873			ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
874			break;
875		case Opt_lookupcache_none:
876			ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
877			break;
878		default:
879			goto out_invalid_value;
880		}
881		break;
882	case Opt_local_lock:
883		trace_nfs_mount_assign(param->key, param->string);
884		switch (result.uint_32) {
885		case Opt_local_lock_all:
886			ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK |
887				       NFS_MOUNT_LOCAL_FCNTL);
888			break;
889		case Opt_local_lock_flock:
890			ctx->flags |= NFS_MOUNT_LOCAL_FLOCK;
891			break;
892		case Opt_local_lock_posix:
893			ctx->flags |= NFS_MOUNT_LOCAL_FCNTL;
894			break;
895		case Opt_local_lock_none:
896			ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
897					NFS_MOUNT_LOCAL_FCNTL);
898			break;
899		default:
900			goto out_invalid_value;
901		}
902		break;
903	case Opt_write:
904		trace_nfs_mount_assign(param->key, param->string);
905		switch (result.uint_32) {
906		case Opt_write_lazy:
907			ctx->flags &=
908				~(NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT);
909			break;
910		case Opt_write_eager:
911			ctx->flags |= NFS_MOUNT_WRITE_EAGER;
912			ctx->flags &= ~NFS_MOUNT_WRITE_WAIT;
913			break;
914		case Opt_write_wait:
915			ctx->flags |=
916				NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT;
917			break;
918		default:
919			goto out_invalid_value;
920		}
921		break;
922
923		/*
924		 * Special options
925		 */
926	case Opt_sloppy:
927		ctx->sloppy = true;
928		break;
929	}
930
931	return 0;
932
933out_invalid_value:
934	return nfs_invalf(fc, "NFS: Bad mount option value specified");
935out_invalid_address:
936	return nfs_invalf(fc, "NFS: Bad IP address specified");
937out_of_bounds:
938	return nfs_invalf(fc, "NFS: Value for '%s' out of range", param->key);
939out_bad_transport:
940	return nfs_invalf(fc, "NFS: Unrecognized transport protocol");
941}
942
943/*
944 * Split fc->source into "hostname:export_path".
945 *
946 * The leftmost colon demarks the split between the server's hostname
947 * and the export path.  If the hostname starts with a left square
948 * bracket, then it may contain colons.
949 *
950 * Note: caller frees hostname and export path, even on error.
951 */
952static int nfs_parse_source(struct fs_context *fc,
953			    size_t maxnamlen, size_t maxpathlen)
954{
955	struct nfs_fs_context *ctx = nfs_fc2context(fc);
956	const char *dev_name = fc->source;
957	size_t len;
958	const char *end;
959
960	if (unlikely(!dev_name || !*dev_name))
961		return -EINVAL;
962
963	/* Is the host name protected with square brakcets? */
964	if (*dev_name == '[') {
965		end = strchr(++dev_name, ']');
966		if (end == NULL || end[1] != ':')
967			goto out_bad_devname;
968
969		len = end - dev_name;
970		end++;
971	} else {
972		const char *comma;
973
974		end = strchr(dev_name, ':');
975		if (end == NULL)
976			goto out_bad_devname;
977		len = end - dev_name;
978
979		/* kill possible hostname list: not supported */
980		comma = memchr(dev_name, ',', len);
981		if (comma)
982			len = comma - dev_name;
983	}
984
985	if (len > maxnamlen)
986		goto out_hostname;
987
988	kfree(ctx->nfs_server.hostname);
989
990	/* N.B. caller will free nfs_server.hostname in all cases */
991	ctx->nfs_server.hostname = kmemdup_nul(dev_name, len, GFP_KERNEL);
992	if (!ctx->nfs_server.hostname)
993		goto out_nomem;
994	len = strlen(++end);
995	if (len > maxpathlen)
996		goto out_path;
997	ctx->nfs_server.export_path = kmemdup_nul(end, len, GFP_KERNEL);
998	if (!ctx->nfs_server.export_path)
999		goto out_nomem;
1000
1001	trace_nfs_mount_path(ctx->nfs_server.export_path);
1002	return 0;
1003
1004out_bad_devname:
1005	return nfs_invalf(fc, "NFS: device name not in host:path format");
1006out_nomem:
1007	nfs_errorf(fc, "NFS: not enough memory to parse device name");
1008	return -ENOMEM;
1009out_hostname:
1010	nfs_errorf(fc, "NFS: server hostname too long");
1011	return -ENAMETOOLONG;
1012out_path:
1013	nfs_errorf(fc, "NFS: export pathname too long");
1014	return -ENAMETOOLONG;
1015}
1016
1017static inline bool is_remount_fc(struct fs_context *fc)
1018{
1019	return fc->root != NULL;
1020}
1021
1022/*
1023 * Parse monolithic NFS2/NFS3 mount data
1024 * - fills in the mount root filehandle
1025 *
1026 * For option strings, user space handles the following behaviors:
1027 *
1028 * + DNS: mapping server host name to IP address ("addr=" option)
1029 *
1030 * + failure mode: how to behave if a mount request can't be handled
1031 *   immediately ("fg/bg" option)
1032 *
1033 * + retry: how often to retry a mount request ("retry=" option)
1034 *
1035 * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1036 *   mountproto=tcp after mountproto=udp, and so on
1037 */
1038static int nfs23_parse_monolithic(struct fs_context *fc,
1039				  struct nfs_mount_data *data)
1040{
1041	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1042	struct nfs_fh *mntfh = ctx->mntfh;
1043	struct sockaddr_storage *sap = &ctx->nfs_server._address;
1044	int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1045	int ret;
1046
1047	if (data == NULL)
1048		goto out_no_data;
1049
1050	ctx->version = NFS_DEFAULT_VERSION;
1051	switch (data->version) {
1052	case 1:
1053		data->namlen = 0;
1054		fallthrough;
1055	case 2:
1056		data->bsize = 0;
1057		fallthrough;
1058	case 3:
1059		if (data->flags & NFS_MOUNT_VER3)
1060			goto out_no_v3;
1061		data->root.size = NFS2_FHSIZE;
1062		memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1063		/* Turn off security negotiation */
1064		extra_flags |= NFS_MOUNT_SECFLAVOUR;
1065		fallthrough;
1066	case 4:
1067		if (data->flags & NFS_MOUNT_SECFLAVOUR)
1068			goto out_no_sec;
1069		fallthrough;
1070	case 5:
1071		memset(data->context, 0, sizeof(data->context));
1072		fallthrough;
1073	case 6:
1074		if (data->flags & NFS_MOUNT_VER3) {
1075			if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1076				goto out_invalid_fh;
1077			mntfh->size = data->root.size;
1078			ctx->version = 3;
1079		} else {
1080			mntfh->size = NFS2_FHSIZE;
1081			ctx->version = 2;
1082		}
1083
1084
1085		memcpy(mntfh->data, data->root.data, mntfh->size);
1086		if (mntfh->size < sizeof(mntfh->data))
1087			memset(mntfh->data + mntfh->size, 0,
1088			       sizeof(mntfh->data) - mntfh->size);
1089
1090		/*
1091		 * for proto == XPRT_TRANSPORT_UDP, which is what uses
1092		 * to_exponential, implying shift: limit the shift value
1093		 * to BITS_PER_LONG (majortimeo is unsigned long)
1094		 */
1095		if (!(data->flags & NFS_MOUNT_TCP)) /* this will be UDP */
1096			if (data->retrans >= 64) /* shift value is too large */
1097				goto out_invalid_data;
1098
1099		/*
1100		 * Translate to nfs_fs_context, which nfs_fill_super
1101		 * can deal with.
1102		 */
1103		ctx->flags	= data->flags & NFS_MOUNT_FLAGMASK;
1104		ctx->flags	|= extra_flags;
1105		ctx->rsize	= data->rsize;
1106		ctx->wsize	= data->wsize;
1107		ctx->timeo	= data->timeo;
1108		ctx->retrans	= data->retrans;
1109		ctx->acregmin	= data->acregmin;
1110		ctx->acregmax	= data->acregmax;
1111		ctx->acdirmin	= data->acdirmin;
1112		ctx->acdirmax	= data->acdirmax;
1113		ctx->need_mount	= false;
1114
1115		memcpy(sap, &data->addr, sizeof(data->addr));
1116		ctx->nfs_server.addrlen = sizeof(data->addr);
1117		ctx->nfs_server.port = ntohs(data->addr.sin_port);
1118		if (sap->ss_family != AF_INET ||
1119		    !nfs_verify_server_address(sap))
1120			goto out_no_address;
1121
1122		if (!(data->flags & NFS_MOUNT_TCP))
1123			ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1124		/* N.B. caller will free nfs_server.hostname in all cases */
1125		ctx->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1126		if (!ctx->nfs_server.hostname)
1127			goto out_nomem;
1128
1129		ctx->namlen		= data->namlen;
1130		ctx->bsize		= data->bsize;
1131
1132		if (data->flags & NFS_MOUNT_SECFLAVOUR)
1133			ctx->selected_flavor = data->pseudoflavor;
1134		else
1135			ctx->selected_flavor = RPC_AUTH_UNIX;
1136
1137		if (!(data->flags & NFS_MOUNT_NONLM))
1138			ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1139					 NFS_MOUNT_LOCAL_FCNTL);
1140		else
1141			ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1142					NFS_MOUNT_LOCAL_FCNTL);
1143
1144		/*
1145		 * The legacy version 6 binary mount data from userspace has a
1146		 * field used only to transport selinux information into the
1147		 * kernel.  To continue to support that functionality we
1148		 * have a touch of selinux knowledge here in the NFS code. The
1149		 * userspace code converted context=blah to just blah so we are
1150		 * converting back to the full string selinux understands.
1151		 */
1152		if (data->context[0]){
1153#ifdef CONFIG_SECURITY_SELINUX
1154			int ret;
1155
1156			data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1157			ret = vfs_parse_fs_string(fc, "context",
1158						  data->context, strlen(data->context));
1159			if (ret < 0)
1160				return ret;
1161#else
1162			return -EINVAL;
1163#endif
1164		}
1165
1166		break;
1167	default:
1168		goto generic;
1169	}
1170
1171	ret = nfs_validate_transport_protocol(fc, ctx);
1172	if (ret)
1173		return ret;
1174
1175	ctx->skip_reconfig_option_check = true;
1176	return 0;
1177
1178generic:
1179	return generic_parse_monolithic(fc, data);
1180
1181out_no_data:
1182	if (is_remount_fc(fc)) {
1183		ctx->skip_reconfig_option_check = true;
1184		return 0;
1185	}
1186	return nfs_invalf(fc, "NFS: mount program didn't pass any mount data");
1187
1188out_no_v3:
1189	return nfs_invalf(fc, "NFS: nfs_mount_data version does not support v3");
1190
1191out_no_sec:
1192	return nfs_invalf(fc, "NFS: nfs_mount_data version supports only AUTH_SYS");
1193
1194out_nomem:
1195	return -ENOMEM;
1196
1197out_no_address:
1198	return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1199
1200out_invalid_fh:
1201	return nfs_invalf(fc, "NFS: invalid root filehandle");
1202
1203out_invalid_data:
1204	return nfs_invalf(fc, "NFS: invalid binary mount data");
1205}
1206
1207#if IS_ENABLED(CONFIG_NFS_V4)
1208struct compat_nfs_string {
1209	compat_uint_t len;
1210	compat_uptr_t data;
1211};
1212
1213static inline void compat_nfs_string(struct nfs_string *dst,
1214				     struct compat_nfs_string *src)
1215{
1216	dst->data = compat_ptr(src->data);
1217	dst->len = src->len;
1218}
1219
1220struct compat_nfs4_mount_data_v1 {
1221	compat_int_t version;
1222	compat_int_t flags;
1223	compat_int_t rsize;
1224	compat_int_t wsize;
1225	compat_int_t timeo;
1226	compat_int_t retrans;
1227	compat_int_t acregmin;
1228	compat_int_t acregmax;
1229	compat_int_t acdirmin;
1230	compat_int_t acdirmax;
1231	struct compat_nfs_string client_addr;
1232	struct compat_nfs_string mnt_path;
1233	struct compat_nfs_string hostname;
1234	compat_uint_t host_addrlen;
1235	compat_uptr_t host_addr;
1236	compat_int_t proto;
1237	compat_int_t auth_flavourlen;
1238	compat_uptr_t auth_flavours;
1239};
1240
1241static void nfs4_compat_mount_data_conv(struct nfs4_mount_data *data)
1242{
1243	struct compat_nfs4_mount_data_v1 *compat =
1244			(struct compat_nfs4_mount_data_v1 *)data;
1245
1246	/* copy the fields backwards */
1247	data->auth_flavours = compat_ptr(compat->auth_flavours);
1248	data->auth_flavourlen = compat->auth_flavourlen;
1249	data->proto = compat->proto;
1250	data->host_addr = compat_ptr(compat->host_addr);
1251	data->host_addrlen = compat->host_addrlen;
1252	compat_nfs_string(&data->hostname, &compat->hostname);
1253	compat_nfs_string(&data->mnt_path, &compat->mnt_path);
1254	compat_nfs_string(&data->client_addr, &compat->client_addr);
1255	data->acdirmax = compat->acdirmax;
1256	data->acdirmin = compat->acdirmin;
1257	data->acregmax = compat->acregmax;
1258	data->acregmin = compat->acregmin;
1259	data->retrans = compat->retrans;
1260	data->timeo = compat->timeo;
1261	data->wsize = compat->wsize;
1262	data->rsize = compat->rsize;
1263	data->flags = compat->flags;
1264	data->version = compat->version;
1265}
1266
1267/*
1268 * Validate NFSv4 mount options
1269 */
1270static int nfs4_parse_monolithic(struct fs_context *fc,
1271				 struct nfs4_mount_data *data)
1272{
1273	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1274	struct sockaddr_storage *sap = &ctx->nfs_server._address;
1275	int ret;
1276	char *c;
1277
1278	if (!data) {
1279		if (is_remount_fc(fc))
1280			goto done;
1281		return nfs_invalf(fc,
1282			"NFS4: mount program didn't pass any mount data");
1283	}
1284
1285	ctx->version = 4;
1286
1287	if (data->version != 1)
1288		return generic_parse_monolithic(fc, data);
1289
1290	if (in_compat_syscall())
1291		nfs4_compat_mount_data_conv(data);
1292
1293	if (data->host_addrlen > sizeof(ctx->nfs_server.address))
1294		goto out_no_address;
1295	if (data->host_addrlen == 0)
1296		goto out_no_address;
1297	ctx->nfs_server.addrlen = data->host_addrlen;
1298	if (copy_from_user(sap, data->host_addr, data->host_addrlen))
1299		return -EFAULT;
1300	if (!nfs_verify_server_address(sap))
1301		goto out_no_address;
1302	ctx->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
1303
1304	if (data->auth_flavourlen) {
1305		rpc_authflavor_t pseudoflavor;
1306
1307		if (data->auth_flavourlen > 1)
1308			goto out_inval_auth;
1309		if (copy_from_user(&pseudoflavor, data->auth_flavours,
1310				   sizeof(pseudoflavor)))
1311			return -EFAULT;
1312		ctx->selected_flavor = pseudoflavor;
1313	} else {
1314		ctx->selected_flavor = RPC_AUTH_UNIX;
1315	}
1316
1317	c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1318	if (IS_ERR(c))
1319		return PTR_ERR(c);
1320	ctx->nfs_server.hostname = c;
1321
1322	c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1323	if (IS_ERR(c))
1324		return PTR_ERR(c);
1325	ctx->nfs_server.export_path = c;
1326	trace_nfs_mount_path(c);
1327
1328	c = strndup_user(data->client_addr.data, 16);
1329	if (IS_ERR(c))
1330		return PTR_ERR(c);
1331	ctx->client_address = c;
1332
1333	/*
1334	 * Translate to nfs_fs_context, which nfs_fill_super
1335	 * can deal with.
1336	 */
1337
1338	ctx->flags	= data->flags & NFS4_MOUNT_FLAGMASK;
1339	ctx->rsize	= data->rsize;
1340	ctx->wsize	= data->wsize;
1341	ctx->timeo	= data->timeo;
1342	ctx->retrans	= data->retrans;
1343	ctx->acregmin	= data->acregmin;
1344	ctx->acregmax	= data->acregmax;
1345	ctx->acdirmin	= data->acdirmin;
1346	ctx->acdirmax	= data->acdirmax;
1347	ctx->nfs_server.protocol = data->proto;
1348	ret = nfs_validate_transport_protocol(fc, ctx);
1349	if (ret)
1350		return ret;
1351done:
1352	ctx->skip_reconfig_option_check = true;
1353	return 0;
1354
1355out_inval_auth:
1356	return nfs_invalf(fc, "NFS4: Invalid number of RPC auth flavours %d",
1357		      data->auth_flavourlen);
1358
1359out_no_address:
1360	return nfs_invalf(fc, "NFS4: mount program didn't pass remote address");
1361}
1362#endif
1363
1364/*
1365 * Parse a monolithic block of data from sys_mount().
1366 */
1367static int nfs_fs_context_parse_monolithic(struct fs_context *fc,
1368					   void *data)
1369{
1370	if (fc->fs_type == &nfs_fs_type)
1371		return nfs23_parse_monolithic(fc, data);
1372
1373#if IS_ENABLED(CONFIG_NFS_V4)
1374	if (fc->fs_type == &nfs4_fs_type)
1375		return nfs4_parse_monolithic(fc, data);
1376#endif
1377
1378	return nfs_invalf(fc, "NFS: Unsupported monolithic data version");
1379}
1380
1381/*
1382 * Validate the preparsed information in the config.
1383 */
1384static int nfs_fs_context_validate(struct fs_context *fc)
1385{
1386	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1387	struct nfs_subversion *nfs_mod;
1388	struct sockaddr_storage *sap = &ctx->nfs_server._address;
1389	int max_namelen = PAGE_SIZE;
1390	int max_pathlen = NFS_MAXPATHLEN;
1391	int port = 0;
1392	int ret;
1393
1394	if (!fc->source)
1395		goto out_no_device_name;
1396
1397	/* Check for sanity first. */
1398	if (ctx->minorversion && ctx->version != 4)
1399		goto out_minorversion_mismatch;
1400
1401	if (ctx->options & NFS_OPTION_MIGRATION &&
1402	    (ctx->version != 4 || ctx->minorversion != 0))
1403		goto out_migration_misuse;
1404
1405	/* Verify that any proto=/mountproto= options match the address
1406	 * families in the addr=/mountaddr= options.
1407	 */
1408	if (ctx->protofamily != AF_UNSPEC &&
1409	    ctx->protofamily != ctx->nfs_server.address.sa_family)
1410		goto out_proto_mismatch;
1411
1412	if (ctx->mountfamily != AF_UNSPEC) {
1413		if (ctx->mount_server.addrlen) {
1414			if (ctx->mountfamily != ctx->mount_server.address.sa_family)
1415				goto out_mountproto_mismatch;
1416		} else {
1417			if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
1418				goto out_mountproto_mismatch;
1419		}
1420	}
1421
1422	if (!nfs_verify_server_address(sap))
1423		goto out_no_address;
1424
1425	ret = nfs_validate_transport_protocol(fc, ctx);
1426	if (ret)
1427		return ret;
1428
1429	if (ctx->version == 4) {
1430		if (IS_ENABLED(CONFIG_NFS_V4)) {
1431			if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1432				port = NFS_RDMA_PORT;
1433			else
1434				port = NFS_PORT;
1435			max_namelen = NFS4_MAXNAMLEN;
1436			max_pathlen = NFS4_MAXPATHLEN;
1437			ctx->flags &= ~(NFS_MOUNT_NONLM | NFS_MOUNT_NOACL |
1438					NFS_MOUNT_VER3 | NFS_MOUNT_LOCAL_FLOCK |
1439					NFS_MOUNT_LOCAL_FCNTL);
1440		} else {
1441			goto out_v4_not_compiled;
1442		}
1443	} else {
1444		nfs_set_mount_transport_protocol(ctx);
1445		if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1446			port = NFS_RDMA_PORT;
1447	}
1448
1449	nfs_set_port(sap, &ctx->nfs_server.port, port);
1450
1451	ret = nfs_parse_source(fc, max_namelen, max_pathlen);
1452	if (ret < 0)
1453		return ret;
1454
1455	/* Load the NFS protocol module if we haven't done so yet */
1456	if (!ctx->nfs_mod) {
1457		nfs_mod = get_nfs_version(ctx->version);
1458		if (IS_ERR(nfs_mod)) {
1459			ret = PTR_ERR(nfs_mod);
1460			goto out_version_unavailable;
1461		}
1462		ctx->nfs_mod = nfs_mod;
1463	}
1464
1465	/* Ensure the filesystem context has the correct fs_type */
1466	if (fc->fs_type != ctx->nfs_mod->nfs_fs) {
1467		module_put(fc->fs_type->owner);
1468		__module_get(ctx->nfs_mod->nfs_fs->owner);
1469		fc->fs_type = ctx->nfs_mod->nfs_fs;
1470	}
1471	return 0;
1472
1473out_no_device_name:
1474	return nfs_invalf(fc, "NFS: Device name not specified");
1475out_v4_not_compiled:
1476	nfs_errorf(fc, "NFS: NFSv4 is not compiled into kernel");
1477	return -EPROTONOSUPPORT;
1478out_no_address:
1479	return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1480out_mountproto_mismatch:
1481	return nfs_invalf(fc, "NFS: Mount server address does not match mountproto= option");
1482out_proto_mismatch:
1483	return nfs_invalf(fc, "NFS: Server address does not match proto= option");
1484out_minorversion_mismatch:
1485	return nfs_invalf(fc, "NFS: Mount option vers=%u does not support minorversion=%u",
1486			  ctx->version, ctx->minorversion);
1487out_migration_misuse:
1488	return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS version");
1489out_version_unavailable:
1490	nfs_errorf(fc, "NFS: Version unavailable");
1491	return ret;
1492}
1493
1494/*
1495 * Create an NFS superblock by the appropriate method.
1496 */
1497static int nfs_get_tree(struct fs_context *fc)
1498{
1499	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1500	int err = nfs_fs_context_validate(fc);
1501
1502	if (err)
1503		return err;
1504	if (!ctx->internal)
1505		return ctx->nfs_mod->rpc_ops->try_get_tree(fc);
1506	else
1507		return nfs_get_tree_common(fc);
1508}
1509
1510/*
1511 * Handle duplication of a configuration.  The caller copied *src into *sc, but
1512 * it can't deal with resource pointers in the filesystem context, so we have
1513 * to do that.  We need to clear pointers, copy data or get extra refs as
1514 * appropriate.
1515 */
1516static int nfs_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1517{
1518	struct nfs_fs_context *src = nfs_fc2context(src_fc), *ctx;
1519
1520	ctx = kmemdup(src, sizeof(struct nfs_fs_context), GFP_KERNEL);
1521	if (!ctx)
1522		return -ENOMEM;
1523
1524	ctx->mntfh = nfs_alloc_fhandle();
1525	if (!ctx->mntfh) {
1526		kfree(ctx);
1527		return -ENOMEM;
1528	}
1529	nfs_copy_fh(ctx->mntfh, src->mntfh);
1530
1531	__module_get(ctx->nfs_mod->owner);
1532	ctx->client_address		= NULL;
1533	ctx->mount_server.hostname	= NULL;
1534	ctx->nfs_server.export_path	= NULL;
1535	ctx->nfs_server.hostname	= NULL;
1536	ctx->fscache_uniq		= NULL;
1537	ctx->clone_data.fattr		= NULL;
1538	fc->fs_private = ctx;
1539	return 0;
1540}
1541
1542static void nfs_fs_context_free(struct fs_context *fc)
1543{
1544	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1545
1546	if (ctx) {
1547		if (ctx->server)
1548			nfs_free_server(ctx->server);
1549		if (ctx->nfs_mod)
1550			put_nfs_version(ctx->nfs_mod);
1551		kfree(ctx->client_address);
1552		kfree(ctx->mount_server.hostname);
1553		kfree(ctx->nfs_server.export_path);
1554		kfree(ctx->nfs_server.hostname);
1555		kfree(ctx->fscache_uniq);
1556		nfs_free_fhandle(ctx->mntfh);
1557		nfs_free_fattr(ctx->clone_data.fattr);
1558		kfree(ctx);
1559	}
1560}
1561
1562static const struct fs_context_operations nfs_fs_context_ops = {
1563	.free			= nfs_fs_context_free,
1564	.dup			= nfs_fs_context_dup,
1565	.parse_param		= nfs_fs_context_parse_param,
1566	.parse_monolithic	= nfs_fs_context_parse_monolithic,
1567	.get_tree		= nfs_get_tree,
1568	.reconfigure		= nfs_reconfigure,
1569};
1570
1571/*
1572 * Prepare superblock configuration.  We use the namespaces attached to the
1573 * context.  This may be the current process's namespaces, or it may be a
1574 * container's namespaces.
1575 */
1576static int nfs_init_fs_context(struct fs_context *fc)
1577{
1578	struct nfs_fs_context *ctx;
1579
1580	ctx = kzalloc(sizeof(struct nfs_fs_context), GFP_KERNEL);
1581	if (unlikely(!ctx))
1582		return -ENOMEM;
1583
1584	ctx->mntfh = nfs_alloc_fhandle();
1585	if (unlikely(!ctx->mntfh)) {
1586		kfree(ctx);
1587		return -ENOMEM;
1588	}
1589
1590	ctx->protofamily	= AF_UNSPEC;
1591	ctx->mountfamily	= AF_UNSPEC;
1592	ctx->mount_server.port	= NFS_UNSPEC_PORT;
1593
1594	if (fc->root) {
1595		/* reconfigure, start with the current config */
1596		struct nfs_server *nfss = fc->root->d_sb->s_fs_info;
1597		struct net *net = nfss->nfs_client->cl_net;
1598
1599		ctx->flags		= nfss->flags;
1600		ctx->rsize		= nfss->rsize;
1601		ctx->wsize		= nfss->wsize;
1602		ctx->retrans		= nfss->client->cl_timeout->to_retries;
1603		ctx->selected_flavor	= nfss->client->cl_auth->au_flavor;
1604		ctx->acregmin		= nfss->acregmin / HZ;
1605		ctx->acregmax		= nfss->acregmax / HZ;
1606		ctx->acdirmin		= nfss->acdirmin / HZ;
1607		ctx->acdirmax		= nfss->acdirmax / HZ;
1608		ctx->timeo		= 10U * nfss->client->cl_timeout->to_initval / HZ;
1609		ctx->nfs_server.port	= nfss->port;
1610		ctx->nfs_server.addrlen	= nfss->nfs_client->cl_addrlen;
1611		ctx->version		= nfss->nfs_client->rpc_ops->version;
1612		ctx->minorversion	= nfss->nfs_client->cl_minorversion;
1613
1614		memcpy(&ctx->nfs_server._address, &nfss->nfs_client->cl_addr,
1615			ctx->nfs_server.addrlen);
1616
1617		if (fc->net_ns != net) {
1618			put_net(fc->net_ns);
1619			fc->net_ns = get_net(net);
1620		}
1621
1622		ctx->nfs_mod = nfss->nfs_client->cl_nfs_mod;
1623		__module_get(ctx->nfs_mod->owner);
1624	} else {
1625		/* defaults */
1626		ctx->timeo		= NFS_UNSPEC_TIMEO;
1627		ctx->retrans		= NFS_UNSPEC_RETRANS;
1628		ctx->acregmin		= NFS_DEF_ACREGMIN;
1629		ctx->acregmax		= NFS_DEF_ACREGMAX;
1630		ctx->acdirmin		= NFS_DEF_ACDIRMIN;
1631		ctx->acdirmax		= NFS_DEF_ACDIRMAX;
1632		ctx->nfs_server.port	= NFS_UNSPEC_PORT;
1633		ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1634		ctx->selected_flavor	= RPC_AUTH_MAXFLAVOR;
1635		ctx->minorversion	= 0;
1636		ctx->need_mount		= true;
1637		ctx->xprtsec.policy	= RPC_XPRTSEC_NONE;
1638		ctx->xprtsec.cert_serial	= TLS_NO_CERT;
1639		ctx->xprtsec.privkey_serial	= TLS_NO_PRIVKEY;
1640
1641		fc->s_iflags		|= SB_I_STABLE_WRITES;
1642	}
1643	fc->fs_private = ctx;
1644	fc->ops = &nfs_fs_context_ops;
1645	return 0;
1646}
1647
1648struct file_system_type nfs_fs_type = {
1649	.owner			= THIS_MODULE,
1650	.name			= "nfs",
1651	.init_fs_context	= nfs_init_fs_context,
1652	.parameters		= nfs_fs_parameters,
1653	.kill_sb		= nfs_kill_super,
1654	.fs_flags		= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1655};
1656MODULE_ALIAS_FS("nfs");
1657EXPORT_SYMBOL_GPL(nfs_fs_type);
1658
1659#if IS_ENABLED(CONFIG_NFS_V4)
1660struct file_system_type nfs4_fs_type = {
1661	.owner			= THIS_MODULE,
1662	.name			= "nfs4",
1663	.init_fs_context	= nfs_init_fs_context,
1664	.parameters		= nfs_fs_parameters,
1665	.kill_sb		= nfs_kill_super,
1666	.fs_flags		= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1667};
1668MODULE_ALIAS_FS("nfs4");
1669MODULE_ALIAS("nfs4");
1670EXPORT_SYMBOL_GPL(nfs4_fs_type);
1671#endif /* CONFIG_NFS_V4 */
1672