xref: /linux/fs/nfs/fs_context.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
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 
39 enum 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_alignwrite,
53 	Opt_fg,
54 	Opt_fscache,
55 	Opt_fscache_flag,
56 	Opt_hard,
57 	Opt_intr,
58 	Opt_local_lock,
59 	Opt_lock,
60 	Opt_lookupcache,
61 	Opt_migration,
62 	Opt_minorversion,
63 	Opt_mountaddr,
64 	Opt_mounthost,
65 	Opt_mountport,
66 	Opt_mountproto,
67 	Opt_mountvers,
68 	Opt_namelen,
69 	Opt_nconnect,
70 	Opt_max_connect,
71 	Opt_port,
72 	Opt_posix,
73 	Opt_proto,
74 	Opt_rdirplus,
75 	Opt_rdma,
76 	Opt_resvport,
77 	Opt_retrans,
78 	Opt_retry,
79 	Opt_rsize,
80 	Opt_sec,
81 	Opt_sharecache,
82 	Opt_sloppy,
83 	Opt_soft,
84 	Opt_softerr,
85 	Opt_softreval,
86 	Opt_source,
87 	Opt_tcp,
88 	Opt_timeo,
89 	Opt_trunkdiscovery,
90 	Opt_udp,
91 	Opt_v,
92 	Opt_vers,
93 	Opt_wsize,
94 	Opt_write,
95 	Opt_xprtsec,
96 };
97 
98 enum {
99 	Opt_local_lock_all,
100 	Opt_local_lock_flock,
101 	Opt_local_lock_none,
102 	Opt_local_lock_posix,
103 };
104 
105 static const struct constant_table nfs_param_enums_local_lock[] = {
106 	{ "all",		Opt_local_lock_all },
107 	{ "flock",	Opt_local_lock_flock },
108 	{ "posix",	Opt_local_lock_posix },
109 	{ "none",		Opt_local_lock_none },
110 	{}
111 };
112 
113 enum {
114 	Opt_lookupcache_all,
115 	Opt_lookupcache_none,
116 	Opt_lookupcache_positive,
117 };
118 
119 static const struct constant_table nfs_param_enums_lookupcache[] = {
120 	{ "all",		Opt_lookupcache_all },
121 	{ "none",		Opt_lookupcache_none },
122 	{ "pos",		Opt_lookupcache_positive },
123 	{ "positive",		Opt_lookupcache_positive },
124 	{}
125 };
126 
127 enum {
128 	Opt_write_lazy,
129 	Opt_write_eager,
130 	Opt_write_wait,
131 };
132 
133 static const struct constant_table nfs_param_enums_write[] = {
134 	{ "lazy",		Opt_write_lazy },
135 	{ "eager",		Opt_write_eager },
136 	{ "wait",		Opt_write_wait },
137 	{}
138 };
139 
140 static const struct fs_parameter_spec nfs_fs_parameters[] = {
141 	fsparam_flag_no("ac",		Opt_ac),
142 	fsparam_u32   ("acdirmax",	Opt_acdirmax),
143 	fsparam_u32   ("acdirmin",	Opt_acdirmin),
144 	fsparam_flag_no("acl",		Opt_acl),
145 	fsparam_u32   ("acregmax",	Opt_acregmax),
146 	fsparam_u32   ("acregmin",	Opt_acregmin),
147 	fsparam_u32   ("actimeo",	Opt_actimeo),
148 	fsparam_string("addr",		Opt_addr),
149 	fsparam_flag  ("bg",		Opt_bg),
150 	fsparam_u32   ("bsize",		Opt_bsize),
151 	fsparam_string("clientaddr",	Opt_clientaddr),
152 	fsparam_flag_no("cto",		Opt_cto),
153 	fsparam_flag_no("alignwrite",	Opt_alignwrite),
154 	fsparam_flag  ("fg",		Opt_fg),
155 	fsparam_flag_no("fsc",		Opt_fscache_flag),
156 	fsparam_string("fsc",		Opt_fscache),
157 	fsparam_flag  ("hard",		Opt_hard),
158 	__fsparam(NULL, "intr",		Opt_intr,
159 		  fs_param_neg_with_no|fs_param_deprecated, NULL),
160 	fsparam_enum  ("local_lock",	Opt_local_lock, nfs_param_enums_local_lock),
161 	fsparam_flag_no("lock",		Opt_lock),
162 	fsparam_enum  ("lookupcache",	Opt_lookupcache, nfs_param_enums_lookupcache),
163 	fsparam_flag_no("migration",	Opt_migration),
164 	fsparam_u32   ("minorversion",	Opt_minorversion),
165 	fsparam_string("mountaddr",	Opt_mountaddr),
166 	fsparam_string("mounthost",	Opt_mounthost),
167 	fsparam_u32   ("mountport",	Opt_mountport),
168 	fsparam_string("mountproto",	Opt_mountproto),
169 	fsparam_u32   ("mountvers",	Opt_mountvers),
170 	fsparam_u32   ("namlen",	Opt_namelen),
171 	fsparam_u32   ("nconnect",	Opt_nconnect),
172 	fsparam_u32   ("max_connect",	Opt_max_connect),
173 	fsparam_string("nfsvers",	Opt_vers),
174 	fsparam_u32   ("port",		Opt_port),
175 	fsparam_flag_no("posix",	Opt_posix),
176 	fsparam_string("proto",		Opt_proto),
177 	fsparam_flag_no("rdirplus",	Opt_rdirplus),
178 	fsparam_flag  ("rdma",		Opt_rdma),
179 	fsparam_flag_no("resvport",	Opt_resvport),
180 	fsparam_u32   ("retrans",	Opt_retrans),
181 	fsparam_string("retry",		Opt_retry),
182 	fsparam_u32   ("rsize",		Opt_rsize),
183 	fsparam_string("sec",		Opt_sec),
184 	fsparam_flag_no("sharecache",	Opt_sharecache),
185 	fsparam_flag  ("sloppy",	Opt_sloppy),
186 	fsparam_flag  ("soft",		Opt_soft),
187 	fsparam_flag  ("softerr",	Opt_softerr),
188 	fsparam_flag  ("softreval",	Opt_softreval),
189 	fsparam_string("source",	Opt_source),
190 	fsparam_flag  ("tcp",		Opt_tcp),
191 	fsparam_u32   ("timeo",		Opt_timeo),
192 	fsparam_flag_no("trunkdiscovery", Opt_trunkdiscovery),
193 	fsparam_flag  ("udp",		Opt_udp),
194 	fsparam_flag  ("v2",		Opt_v),
195 	fsparam_flag  ("v3",		Opt_v),
196 	fsparam_flag  ("v4",		Opt_v),
197 	fsparam_flag  ("v4.0",		Opt_v),
198 	fsparam_flag  ("v4.1",		Opt_v),
199 	fsparam_flag  ("v4.2",		Opt_v),
200 	fsparam_string("vers",		Opt_vers),
201 	fsparam_enum  ("write",		Opt_write, nfs_param_enums_write),
202 	fsparam_u32   ("wsize",		Opt_wsize),
203 	fsparam_string("xprtsec",	Opt_xprtsec),
204 	{}
205 };
206 
207 enum {
208 	Opt_vers_2,
209 	Opt_vers_3,
210 	Opt_vers_4,
211 	Opt_vers_4_0,
212 	Opt_vers_4_1,
213 	Opt_vers_4_2,
214 };
215 
216 static const struct constant_table nfs_vers_tokens[] = {
217 	{ "2",		Opt_vers_2 },
218 	{ "3",		Opt_vers_3 },
219 	{ "4",		Opt_vers_4 },
220 	{ "4.0",	Opt_vers_4_0 },
221 	{ "4.1",	Opt_vers_4_1 },
222 	{ "4.2",	Opt_vers_4_2 },
223 	{}
224 };
225 
226 enum {
227 	Opt_xprt_rdma,
228 	Opt_xprt_rdma6,
229 	Opt_xprt_tcp,
230 	Opt_xprt_tcp6,
231 	Opt_xprt_udp,
232 	Opt_xprt_udp6,
233 	nr__Opt_xprt
234 };
235 
236 static const struct constant_table nfs_xprt_protocol_tokens[] = {
237 	{ "rdma",	Opt_xprt_rdma },
238 	{ "rdma6",	Opt_xprt_rdma6 },
239 	{ "tcp",	Opt_xprt_tcp },
240 	{ "tcp6",	Opt_xprt_tcp6 },
241 	{ "udp",	Opt_xprt_udp },
242 	{ "udp6",	Opt_xprt_udp6 },
243 	{}
244 };
245 
246 enum {
247 	Opt_sec_krb5,
248 	Opt_sec_krb5i,
249 	Opt_sec_krb5p,
250 	Opt_sec_lkey,
251 	Opt_sec_lkeyi,
252 	Opt_sec_lkeyp,
253 	Opt_sec_none,
254 	Opt_sec_spkm,
255 	Opt_sec_spkmi,
256 	Opt_sec_spkmp,
257 	Opt_sec_sys,
258 	nr__Opt_sec
259 };
260 
261 static const struct constant_table nfs_secflavor_tokens[] = {
262 	{ "krb5",	Opt_sec_krb5 },
263 	{ "krb5i",	Opt_sec_krb5i },
264 	{ "krb5p",	Opt_sec_krb5p },
265 	{ "lkey",	Opt_sec_lkey },
266 	{ "lkeyi",	Opt_sec_lkeyi },
267 	{ "lkeyp",	Opt_sec_lkeyp },
268 	{ "none",	Opt_sec_none },
269 	{ "null",	Opt_sec_none },
270 	{ "spkm3",	Opt_sec_spkm },
271 	{ "spkm3i",	Opt_sec_spkmi },
272 	{ "spkm3p",	Opt_sec_spkmp },
273 	{ "sys",	Opt_sec_sys },
274 	{}
275 };
276 
277 enum {
278 	Opt_xprtsec_none,
279 	Opt_xprtsec_tls,
280 	Opt_xprtsec_mtls,
281 	nr__Opt_xprtsec
282 };
283 
284 static const struct constant_table nfs_xprtsec_policies[] = {
285 	{ "none",	Opt_xprtsec_none },
286 	{ "tls",	Opt_xprtsec_tls },
287 	{ "mtls",	Opt_xprtsec_mtls },
288 	{}
289 };
290 
291 /*
292  * Sanity-check a server address provided by the mount command.
293  *
294  * Address family must be initialized, and address must not be
295  * the ANY address for that family.
296  */
297 static int nfs_verify_server_address(struct sockaddr_storage *addr)
298 {
299 	switch (addr->ss_family) {
300 	case AF_INET: {
301 		struct sockaddr_in *sa = (struct sockaddr_in *)addr;
302 		return sa->sin_addr.s_addr != htonl(INADDR_ANY);
303 	}
304 	case AF_INET6: {
305 		struct in6_addr *sa = &((struct sockaddr_in6 *)addr)->sin6_addr;
306 		return !ipv6_addr_any(sa);
307 	}
308 	}
309 
310 	return 0;
311 }
312 
313 #ifdef CONFIG_NFS_DISABLE_UDP_SUPPORT
314 static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
315 {
316 	return true;
317 }
318 #else
319 static bool nfs_server_transport_udp_invalid(const struct nfs_fs_context *ctx)
320 {
321 	if (ctx->version == 4)
322 		return true;
323 	return false;
324 }
325 #endif
326 
327 /*
328  * Sanity check the NFS transport protocol.
329  */
330 static int nfs_validate_transport_protocol(struct fs_context *fc,
331 					   struct nfs_fs_context *ctx)
332 {
333 	switch (ctx->nfs_server.protocol) {
334 	case XPRT_TRANSPORT_UDP:
335 		if (nfs_server_transport_udp_invalid(ctx))
336 			goto out_invalid_transport_udp;
337 		break;
338 	case XPRT_TRANSPORT_TCP:
339 	case XPRT_TRANSPORT_RDMA:
340 		break;
341 	default:
342 		ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
343 	}
344 
345 	if (ctx->xprtsec.policy != RPC_XPRTSEC_NONE)
346 		switch (ctx->nfs_server.protocol) {
347 		case XPRT_TRANSPORT_TCP:
348 			ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP_TLS;
349 			break;
350 		default:
351 			goto out_invalid_xprtsec_policy;
352 	}
353 
354 	return 0;
355 out_invalid_transport_udp:
356 	return nfs_invalf(fc, "NFS: Unsupported transport protocol udp");
357 out_invalid_xprtsec_policy:
358 	return nfs_invalf(fc, "NFS: Transport does not support xprtsec");
359 }
360 
361 /*
362  * For text based NFSv2/v3 mounts, the mount protocol transport default
363  * settings should depend upon the specified NFS transport.
364  */
365 static void nfs_set_mount_transport_protocol(struct nfs_fs_context *ctx)
366 {
367 	if (ctx->mount_server.protocol == XPRT_TRANSPORT_UDP ||
368 	    ctx->mount_server.protocol == XPRT_TRANSPORT_TCP)
369 			return;
370 	switch (ctx->nfs_server.protocol) {
371 	case XPRT_TRANSPORT_UDP:
372 		ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
373 		break;
374 	case XPRT_TRANSPORT_TCP:
375 	case XPRT_TRANSPORT_RDMA:
376 		ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
377 	}
378 }
379 
380 /*
381  * Add 'flavor' to 'auth_info' if not already present.
382  * Returns true if 'flavor' ends up in the list, false otherwise
383  */
384 static int nfs_auth_info_add(struct fs_context *fc,
385 			     struct nfs_auth_info *auth_info,
386 			     rpc_authflavor_t flavor)
387 {
388 	unsigned int i;
389 	unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
390 
391 	/* make sure this flavor isn't already in the list */
392 	for (i = 0; i < auth_info->flavor_len; i++) {
393 		if (flavor == auth_info->flavors[i])
394 			return 0;
395 	}
396 
397 	if (auth_info->flavor_len + 1 >= max_flavor_len)
398 		return nfs_invalf(fc, "NFS: too many sec= flavors");
399 
400 	auth_info->flavors[auth_info->flavor_len++] = flavor;
401 	return 0;
402 }
403 
404 /*
405  * Parse the value of the 'sec=' option.
406  */
407 static int nfs_parse_security_flavors(struct fs_context *fc,
408 				      struct fs_parameter *param)
409 {
410 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
411 	rpc_authflavor_t pseudoflavor;
412 	char *string = param->string, *p;
413 	int ret;
414 
415 	trace_nfs_mount_assign(param->key, string);
416 
417 	while ((p = strsep(&string, ":")) != NULL) {
418 		if (!*p)
419 			continue;
420 		switch (lookup_constant(nfs_secflavor_tokens, p, -1)) {
421 		case Opt_sec_none:
422 			pseudoflavor = RPC_AUTH_NULL;
423 			break;
424 		case Opt_sec_sys:
425 			pseudoflavor = RPC_AUTH_UNIX;
426 			break;
427 		case Opt_sec_krb5:
428 			pseudoflavor = RPC_AUTH_GSS_KRB5;
429 			break;
430 		case Opt_sec_krb5i:
431 			pseudoflavor = RPC_AUTH_GSS_KRB5I;
432 			break;
433 		case Opt_sec_krb5p:
434 			pseudoflavor = RPC_AUTH_GSS_KRB5P;
435 			break;
436 		case Opt_sec_lkey:
437 			pseudoflavor = RPC_AUTH_GSS_LKEY;
438 			break;
439 		case Opt_sec_lkeyi:
440 			pseudoflavor = RPC_AUTH_GSS_LKEYI;
441 			break;
442 		case Opt_sec_lkeyp:
443 			pseudoflavor = RPC_AUTH_GSS_LKEYP;
444 			break;
445 		case Opt_sec_spkm:
446 			pseudoflavor = RPC_AUTH_GSS_SPKM;
447 			break;
448 		case Opt_sec_spkmi:
449 			pseudoflavor = RPC_AUTH_GSS_SPKMI;
450 			break;
451 		case Opt_sec_spkmp:
452 			pseudoflavor = RPC_AUTH_GSS_SPKMP;
453 			break;
454 		default:
455 			return nfs_invalf(fc, "NFS: sec=%s option not recognized", p);
456 		}
457 
458 		ret = nfs_auth_info_add(fc, &ctx->auth_info, pseudoflavor);
459 		if (ret < 0)
460 			return ret;
461 	}
462 
463 	return 0;
464 }
465 
466 static int nfs_parse_xprtsec_policy(struct fs_context *fc,
467 				    struct fs_parameter *param)
468 {
469 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
470 
471 	trace_nfs_mount_assign(param->key, param->string);
472 
473 	switch (lookup_constant(nfs_xprtsec_policies, param->string, -1)) {
474 	case Opt_xprtsec_none:
475 		ctx->xprtsec.policy = RPC_XPRTSEC_NONE;
476 		break;
477 	case Opt_xprtsec_tls:
478 		ctx->xprtsec.policy = RPC_XPRTSEC_TLS_ANON;
479 		break;
480 	case Opt_xprtsec_mtls:
481 		ctx->xprtsec.policy = RPC_XPRTSEC_TLS_X509;
482 		break;
483 	default:
484 		return nfs_invalf(fc, "NFS: Unrecognized transport security policy");
485 	}
486 	return 0;
487 }
488 
489 static int nfs_parse_version_string(struct fs_context *fc,
490 				    const char *string)
491 {
492 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
493 
494 	ctx->flags &= ~NFS_MOUNT_VER3;
495 	switch (lookup_constant(nfs_vers_tokens, string, -1)) {
496 	case Opt_vers_2:
497 		ctx->version = 2;
498 		break;
499 	case Opt_vers_3:
500 		ctx->flags |= NFS_MOUNT_VER3;
501 		ctx->version = 3;
502 		break;
503 	case Opt_vers_4:
504 		/* Backward compatibility option. In future,
505 		 * the mount program should always supply
506 		 * a NFSv4 minor version number.
507 		 */
508 		ctx->version = 4;
509 		break;
510 	case Opt_vers_4_0:
511 		ctx->version = 4;
512 		ctx->minorversion = 0;
513 		break;
514 	case Opt_vers_4_1:
515 		ctx->version = 4;
516 		ctx->minorversion = 1;
517 		break;
518 	case Opt_vers_4_2:
519 		ctx->version = 4;
520 		ctx->minorversion = 2;
521 		break;
522 	default:
523 		return nfs_invalf(fc, "NFS: Unsupported NFS version");
524 	}
525 	return 0;
526 }
527 
528 /*
529  * Parse a single mount parameter.
530  */
531 static int nfs_fs_context_parse_param(struct fs_context *fc,
532 				      struct fs_parameter *param)
533 {
534 	struct fs_parse_result result;
535 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
536 	unsigned short protofamily, mountfamily;
537 	unsigned int len;
538 	int ret, opt;
539 
540 	trace_nfs_mount_option(param);
541 
542 	opt = fs_parse(fc, nfs_fs_parameters, param, &result);
543 	if (opt < 0)
544 		return (opt == -ENOPARAM && ctx->sloppy) ? 1 : opt;
545 
546 	if (fc->security)
547 		ctx->has_sec_mnt_opts = 1;
548 
549 	switch (opt) {
550 	case Opt_source:
551 		if (fc->source)
552 			return nfs_invalf(fc, "NFS: Multiple sources not supported");
553 		fc->source = param->string;
554 		param->string = NULL;
555 		break;
556 
557 		/*
558 		 * boolean options:  foo/nofoo
559 		 */
560 	case Opt_soft:
561 		ctx->flags |= NFS_MOUNT_SOFT;
562 		ctx->flags &= ~NFS_MOUNT_SOFTERR;
563 		break;
564 	case Opt_softerr:
565 		ctx->flags |= NFS_MOUNT_SOFTERR | NFS_MOUNT_SOFTREVAL;
566 		ctx->flags &= ~NFS_MOUNT_SOFT;
567 		break;
568 	case Opt_hard:
569 		ctx->flags &= ~(NFS_MOUNT_SOFT |
570 				NFS_MOUNT_SOFTERR |
571 				NFS_MOUNT_SOFTREVAL);
572 		break;
573 	case Opt_softreval:
574 		if (result.negated)
575 			ctx->flags &= ~NFS_MOUNT_SOFTREVAL;
576 		else
577 			ctx->flags |= NFS_MOUNT_SOFTREVAL;
578 		break;
579 	case Opt_posix:
580 		if (result.negated)
581 			ctx->flags &= ~NFS_MOUNT_POSIX;
582 		else
583 			ctx->flags |= NFS_MOUNT_POSIX;
584 		break;
585 	case Opt_cto:
586 		if (result.negated)
587 			ctx->flags |= NFS_MOUNT_NOCTO;
588 		else
589 			ctx->flags &= ~NFS_MOUNT_NOCTO;
590 		break;
591 	case Opt_trunkdiscovery:
592 		if (result.negated)
593 			ctx->flags &= ~NFS_MOUNT_TRUNK_DISCOVERY;
594 		else
595 			ctx->flags |= NFS_MOUNT_TRUNK_DISCOVERY;
596 		break;
597 	case Opt_alignwrite:
598 		if (result.negated)
599 			ctx->flags |= NFS_MOUNT_NO_ALIGNWRITE;
600 		else
601 			ctx->flags &= ~NFS_MOUNT_NO_ALIGNWRITE;
602 		break;
603 	case Opt_ac:
604 		if (result.negated)
605 			ctx->flags |= NFS_MOUNT_NOAC;
606 		else
607 			ctx->flags &= ~NFS_MOUNT_NOAC;
608 		break;
609 	case Opt_lock:
610 		if (result.negated) {
611 			ctx->lock_status = NFS_LOCK_NOLOCK;
612 			ctx->flags |= NFS_MOUNT_NONLM;
613 			ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
614 		} else {
615 			ctx->lock_status = NFS_LOCK_LOCK;
616 			ctx->flags &= ~NFS_MOUNT_NONLM;
617 			ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
618 		}
619 		break;
620 	case Opt_udp:
621 		ctx->flags &= ~NFS_MOUNT_TCP;
622 		ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
623 		break;
624 	case Opt_tcp:
625 	case Opt_rdma:
626 		ctx->flags |= NFS_MOUNT_TCP; /* for side protocols */
627 		ret = xprt_find_transport_ident(param->key);
628 		if (ret < 0)
629 			goto out_bad_transport;
630 		ctx->nfs_server.protocol = ret;
631 		break;
632 	case Opt_acl:
633 		if (result.negated)
634 			ctx->flags |= NFS_MOUNT_NOACL;
635 		else
636 			ctx->flags &= ~NFS_MOUNT_NOACL;
637 		break;
638 	case Opt_rdirplus:
639 		if (result.negated)
640 			ctx->flags |= NFS_MOUNT_NORDIRPLUS;
641 		else
642 			ctx->flags &= ~NFS_MOUNT_NORDIRPLUS;
643 		break;
644 	case Opt_sharecache:
645 		if (result.negated)
646 			ctx->flags |= NFS_MOUNT_UNSHARED;
647 		else
648 			ctx->flags &= ~NFS_MOUNT_UNSHARED;
649 		break;
650 	case Opt_resvport:
651 		if (result.negated)
652 			ctx->flags |= NFS_MOUNT_NORESVPORT;
653 		else
654 			ctx->flags &= ~NFS_MOUNT_NORESVPORT;
655 		break;
656 	case Opt_fscache_flag:
657 		if (result.negated)
658 			ctx->options &= ~NFS_OPTION_FSCACHE;
659 		else
660 			ctx->options |= NFS_OPTION_FSCACHE;
661 		kfree(ctx->fscache_uniq);
662 		ctx->fscache_uniq = NULL;
663 		break;
664 	case Opt_fscache:
665 		trace_nfs_mount_assign(param->key, param->string);
666 		ctx->options |= NFS_OPTION_FSCACHE;
667 		kfree(ctx->fscache_uniq);
668 		ctx->fscache_uniq = param->string;
669 		param->string = NULL;
670 		break;
671 	case Opt_migration:
672 		if (result.negated)
673 			ctx->options &= ~NFS_OPTION_MIGRATION;
674 		else
675 			ctx->options |= NFS_OPTION_MIGRATION;
676 		break;
677 
678 		/*
679 		 * options that take numeric values
680 		 */
681 	case Opt_port:
682 		if (result.uint_32 > USHRT_MAX)
683 			goto out_of_bounds;
684 		ctx->nfs_server.port = result.uint_32;
685 		break;
686 	case Opt_rsize:
687 		ctx->rsize = result.uint_32;
688 		break;
689 	case Opt_wsize:
690 		ctx->wsize = result.uint_32;
691 		break;
692 	case Opt_bsize:
693 		ctx->bsize = result.uint_32;
694 		break;
695 	case Opt_timeo:
696 		if (result.uint_32 < 1 || result.uint_32 > INT_MAX)
697 			goto out_of_bounds;
698 		ctx->timeo = result.uint_32;
699 		break;
700 	case Opt_retrans:
701 		if (result.uint_32 > INT_MAX)
702 			goto out_of_bounds;
703 		ctx->retrans = result.uint_32;
704 		break;
705 	case Opt_acregmin:
706 		ctx->acregmin = result.uint_32;
707 		break;
708 	case Opt_acregmax:
709 		ctx->acregmax = result.uint_32;
710 		break;
711 	case Opt_acdirmin:
712 		ctx->acdirmin = result.uint_32;
713 		break;
714 	case Opt_acdirmax:
715 		ctx->acdirmax = result.uint_32;
716 		break;
717 	case Opt_actimeo:
718 		ctx->acregmin = result.uint_32;
719 		ctx->acregmax = result.uint_32;
720 		ctx->acdirmin = result.uint_32;
721 		ctx->acdirmax = result.uint_32;
722 		break;
723 	case Opt_namelen:
724 		ctx->namlen = result.uint_32;
725 		break;
726 	case Opt_mountport:
727 		if (result.uint_32 > USHRT_MAX)
728 			goto out_of_bounds;
729 		ctx->mount_server.port = result.uint_32;
730 		break;
731 	case Opt_mountvers:
732 		if (result.uint_32 < NFS_MNT_VERSION ||
733 		    result.uint_32 > NFS_MNT3_VERSION)
734 			goto out_of_bounds;
735 		ctx->mount_server.version = result.uint_32;
736 		break;
737 	case Opt_minorversion:
738 		if (result.uint_32 > NFS4_MAX_MINOR_VERSION)
739 			goto out_of_bounds;
740 		ctx->minorversion = result.uint_32;
741 		break;
742 
743 		/*
744 		 * options that take text values
745 		 */
746 	case Opt_v:
747 		ret = nfs_parse_version_string(fc, param->key + 1);
748 		if (ret < 0)
749 			return ret;
750 		break;
751 	case Opt_vers:
752 		if (!param->string)
753 			goto out_invalid_value;
754 		trace_nfs_mount_assign(param->key, param->string);
755 		ret = nfs_parse_version_string(fc, param->string);
756 		if (ret < 0)
757 			return ret;
758 		break;
759 	case Opt_sec:
760 		ret = nfs_parse_security_flavors(fc, param);
761 		if (ret < 0)
762 			return ret;
763 		break;
764 	case Opt_xprtsec:
765 		ret = nfs_parse_xprtsec_policy(fc, param);
766 		if (ret < 0)
767 			return ret;
768 		break;
769 
770 	case Opt_proto:
771 		if (!param->string)
772 			goto out_invalid_value;
773 		trace_nfs_mount_assign(param->key, param->string);
774 		protofamily = AF_INET;
775 		switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
776 		case Opt_xprt_udp6:
777 			protofamily = AF_INET6;
778 			fallthrough;
779 		case Opt_xprt_udp:
780 			ctx->flags &= ~NFS_MOUNT_TCP;
781 			ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
782 			break;
783 		case Opt_xprt_tcp6:
784 			protofamily = AF_INET6;
785 			fallthrough;
786 		case Opt_xprt_tcp:
787 			ctx->flags |= NFS_MOUNT_TCP;
788 			ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
789 			break;
790 		case Opt_xprt_rdma6:
791 			protofamily = AF_INET6;
792 			fallthrough;
793 		case Opt_xprt_rdma:
794 			/* vector side protocols to TCP */
795 			ctx->flags |= NFS_MOUNT_TCP;
796 			ret = xprt_find_transport_ident(param->string);
797 			if (ret < 0)
798 				goto out_bad_transport;
799 			ctx->nfs_server.protocol = ret;
800 			break;
801 		default:
802 			goto out_bad_transport;
803 		}
804 
805 		ctx->protofamily = protofamily;
806 		break;
807 
808 	case Opt_mountproto:
809 		if (!param->string)
810 			goto out_invalid_value;
811 		trace_nfs_mount_assign(param->key, param->string);
812 		mountfamily = AF_INET;
813 		switch (lookup_constant(nfs_xprt_protocol_tokens, param->string, -1)) {
814 		case Opt_xprt_udp6:
815 			mountfamily = AF_INET6;
816 			fallthrough;
817 		case Opt_xprt_udp:
818 			ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
819 			break;
820 		case Opt_xprt_tcp6:
821 			mountfamily = AF_INET6;
822 			fallthrough;
823 		case Opt_xprt_tcp:
824 			ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
825 			break;
826 		case Opt_xprt_rdma: /* not used for side protocols */
827 		default:
828 			goto out_bad_transport;
829 		}
830 		ctx->mountfamily = mountfamily;
831 		break;
832 
833 	case Opt_addr:
834 		trace_nfs_mount_assign(param->key, param->string);
835 		len = rpc_pton(fc->net_ns, param->string, param->size,
836 			       &ctx->nfs_server.address,
837 			       sizeof(ctx->nfs_server._address));
838 		if (len == 0)
839 			goto out_invalid_address;
840 		ctx->nfs_server.addrlen = len;
841 		break;
842 	case Opt_clientaddr:
843 		trace_nfs_mount_assign(param->key, param->string);
844 		kfree(ctx->client_address);
845 		ctx->client_address = param->string;
846 		param->string = NULL;
847 		break;
848 	case Opt_mounthost:
849 		trace_nfs_mount_assign(param->key, param->string);
850 		kfree(ctx->mount_server.hostname);
851 		ctx->mount_server.hostname = param->string;
852 		param->string = NULL;
853 		break;
854 	case Opt_mountaddr:
855 		trace_nfs_mount_assign(param->key, param->string);
856 		len = rpc_pton(fc->net_ns, param->string, param->size,
857 			       &ctx->mount_server.address,
858 			       sizeof(ctx->mount_server._address));
859 		if (len == 0)
860 			goto out_invalid_address;
861 		ctx->mount_server.addrlen = len;
862 		break;
863 	case Opt_nconnect:
864 		trace_nfs_mount_assign(param->key, param->string);
865 		if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_CONNECTIONS)
866 			goto out_of_bounds;
867 		ctx->nfs_server.nconnect = result.uint_32;
868 		break;
869 	case Opt_max_connect:
870 		trace_nfs_mount_assign(param->key, param->string);
871 		if (result.uint_32 < 1 || result.uint_32 > NFS_MAX_TRANSPORTS)
872 			goto out_of_bounds;
873 		ctx->nfs_server.max_connect = result.uint_32;
874 		break;
875 	case Opt_lookupcache:
876 		trace_nfs_mount_assign(param->key, param->string);
877 		switch (result.uint_32) {
878 		case Opt_lookupcache_all:
879 			ctx->flags &= ~(NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE);
880 			break;
881 		case Opt_lookupcache_positive:
882 			ctx->flags &= ~NFS_MOUNT_LOOKUP_CACHE_NONE;
883 			ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG;
884 			break;
885 		case Opt_lookupcache_none:
886 			ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
887 			break;
888 		default:
889 			goto out_invalid_value;
890 		}
891 		break;
892 	case Opt_local_lock:
893 		trace_nfs_mount_assign(param->key, param->string);
894 		switch (result.uint_32) {
895 		case Opt_local_lock_all:
896 			ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK |
897 				       NFS_MOUNT_LOCAL_FCNTL);
898 			break;
899 		case Opt_local_lock_flock:
900 			ctx->flags |= NFS_MOUNT_LOCAL_FLOCK;
901 			break;
902 		case Opt_local_lock_posix:
903 			ctx->flags |= NFS_MOUNT_LOCAL_FCNTL;
904 			break;
905 		case Opt_local_lock_none:
906 			ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
907 					NFS_MOUNT_LOCAL_FCNTL);
908 			break;
909 		default:
910 			goto out_invalid_value;
911 		}
912 		break;
913 	case Opt_write:
914 		trace_nfs_mount_assign(param->key, param->string);
915 		switch (result.uint_32) {
916 		case Opt_write_lazy:
917 			ctx->flags &=
918 				~(NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT);
919 			break;
920 		case Opt_write_eager:
921 			ctx->flags |= NFS_MOUNT_WRITE_EAGER;
922 			ctx->flags &= ~NFS_MOUNT_WRITE_WAIT;
923 			break;
924 		case Opt_write_wait:
925 			ctx->flags |=
926 				NFS_MOUNT_WRITE_EAGER | NFS_MOUNT_WRITE_WAIT;
927 			break;
928 		default:
929 			goto out_invalid_value;
930 		}
931 		break;
932 
933 		/*
934 		 * Special options
935 		 */
936 	case Opt_sloppy:
937 		ctx->sloppy = true;
938 		break;
939 	}
940 
941 	return 0;
942 
943 out_invalid_value:
944 	return nfs_invalf(fc, "NFS: Bad mount option value specified");
945 out_invalid_address:
946 	return nfs_invalf(fc, "NFS: Bad IP address specified");
947 out_of_bounds:
948 	return nfs_invalf(fc, "NFS: Value for '%s' out of range", param->key);
949 out_bad_transport:
950 	return nfs_invalf(fc, "NFS: Unrecognized transport protocol");
951 }
952 
953 /*
954  * Split fc->source into "hostname:export_path".
955  *
956  * The leftmost colon demarks the split between the server's hostname
957  * and the export path.  If the hostname starts with a left square
958  * bracket, then it may contain colons.
959  *
960  * Note: caller frees hostname and export path, even on error.
961  */
962 static int nfs_parse_source(struct fs_context *fc,
963 			    size_t maxnamlen, size_t maxpathlen)
964 {
965 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
966 	const char *dev_name = fc->source;
967 	size_t len;
968 	const char *end;
969 
970 	if (unlikely(!dev_name || !*dev_name))
971 		return -EINVAL;
972 
973 	/* Is the host name protected with square brakcets? */
974 	if (*dev_name == '[') {
975 		end = strchr(++dev_name, ']');
976 		if (end == NULL || end[1] != ':')
977 			goto out_bad_devname;
978 
979 		len = end - dev_name;
980 		end++;
981 	} else {
982 		const char *comma;
983 
984 		end = strchr(dev_name, ':');
985 		if (end == NULL)
986 			goto out_bad_devname;
987 		len = end - dev_name;
988 
989 		/* kill possible hostname list: not supported */
990 		comma = memchr(dev_name, ',', len);
991 		if (comma)
992 			len = comma - dev_name;
993 	}
994 
995 	if (len > maxnamlen)
996 		goto out_hostname;
997 
998 	kfree(ctx->nfs_server.hostname);
999 
1000 	/* N.B. caller will free nfs_server.hostname in all cases */
1001 	ctx->nfs_server.hostname = kmemdup_nul(dev_name, len, GFP_KERNEL);
1002 	if (!ctx->nfs_server.hostname)
1003 		goto out_nomem;
1004 	len = strlen(++end);
1005 	if (len > maxpathlen)
1006 		goto out_path;
1007 	ctx->nfs_server.export_path = kmemdup_nul(end, len, GFP_KERNEL);
1008 	if (!ctx->nfs_server.export_path)
1009 		goto out_nomem;
1010 
1011 	trace_nfs_mount_path(ctx->nfs_server.export_path);
1012 	return 0;
1013 
1014 out_bad_devname:
1015 	return nfs_invalf(fc, "NFS: device name not in host:path format");
1016 out_nomem:
1017 	nfs_errorf(fc, "NFS: not enough memory to parse device name");
1018 	return -ENOMEM;
1019 out_hostname:
1020 	nfs_errorf(fc, "NFS: server hostname too long");
1021 	return -ENAMETOOLONG;
1022 out_path:
1023 	nfs_errorf(fc, "NFS: export pathname too long");
1024 	return -ENAMETOOLONG;
1025 }
1026 
1027 static inline bool is_remount_fc(struct fs_context *fc)
1028 {
1029 	return fc->root != NULL;
1030 }
1031 
1032 /*
1033  * Parse monolithic NFS2/NFS3 mount data
1034  * - fills in the mount root filehandle
1035  *
1036  * For option strings, user space handles the following behaviors:
1037  *
1038  * + DNS: mapping server host name to IP address ("addr=" option)
1039  *
1040  * + failure mode: how to behave if a mount request can't be handled
1041  *   immediately ("fg/bg" option)
1042  *
1043  * + retry: how often to retry a mount request ("retry=" option)
1044  *
1045  * + breaking back: trying proto=udp after proto=tcp, v2 after v3,
1046  *   mountproto=tcp after mountproto=udp, and so on
1047  */
1048 static int nfs23_parse_monolithic(struct fs_context *fc,
1049 				  struct nfs_mount_data *data)
1050 {
1051 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1052 	struct nfs_fh *mntfh = ctx->mntfh;
1053 	struct sockaddr_storage *sap = &ctx->nfs_server._address;
1054 	int extra_flags = NFS_MOUNT_LEGACY_INTERFACE;
1055 	int ret;
1056 
1057 	if (data == NULL)
1058 		goto out_no_data;
1059 
1060 	ctx->version = NFS_DEFAULT_VERSION;
1061 	switch (data->version) {
1062 	case 1:
1063 		data->namlen = 0;
1064 		fallthrough;
1065 	case 2:
1066 		data->bsize = 0;
1067 		fallthrough;
1068 	case 3:
1069 		if (data->flags & NFS_MOUNT_VER3)
1070 			goto out_no_v3;
1071 		data->root.size = NFS2_FHSIZE;
1072 		memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE);
1073 		/* Turn off security negotiation */
1074 		extra_flags |= NFS_MOUNT_SECFLAVOUR;
1075 		fallthrough;
1076 	case 4:
1077 		if (data->flags & NFS_MOUNT_SECFLAVOUR)
1078 			goto out_no_sec;
1079 		fallthrough;
1080 	case 5:
1081 		memset(data->context, 0, sizeof(data->context));
1082 		fallthrough;
1083 	case 6:
1084 		if (data->flags & NFS_MOUNT_VER3) {
1085 			if (data->root.size > NFS3_FHSIZE || data->root.size == 0)
1086 				goto out_invalid_fh;
1087 			mntfh->size = data->root.size;
1088 			ctx->version = 3;
1089 		} else {
1090 			mntfh->size = NFS2_FHSIZE;
1091 			ctx->version = 2;
1092 		}
1093 
1094 
1095 		memcpy(mntfh->data, data->root.data, mntfh->size);
1096 		if (mntfh->size < sizeof(mntfh->data))
1097 			memset(mntfh->data + mntfh->size, 0,
1098 			       sizeof(mntfh->data) - mntfh->size);
1099 
1100 		/*
1101 		 * for proto == XPRT_TRANSPORT_UDP, which is what uses
1102 		 * to_exponential, implying shift: limit the shift value
1103 		 * to BITS_PER_LONG (majortimeo is unsigned long)
1104 		 */
1105 		if (!(data->flags & NFS_MOUNT_TCP)) /* this will be UDP */
1106 			if (data->retrans >= 64) /* shift value is too large */
1107 				goto out_invalid_data;
1108 
1109 		/*
1110 		 * Translate to nfs_fs_context, which nfs_fill_super
1111 		 * can deal with.
1112 		 */
1113 		ctx->flags	= data->flags & NFS_MOUNT_FLAGMASK;
1114 		ctx->flags	|= extra_flags;
1115 		ctx->rsize	= data->rsize;
1116 		ctx->wsize	= data->wsize;
1117 		ctx->timeo	= data->timeo;
1118 		ctx->retrans	= data->retrans;
1119 		ctx->acregmin	= data->acregmin;
1120 		ctx->acregmax	= data->acregmax;
1121 		ctx->acdirmin	= data->acdirmin;
1122 		ctx->acdirmax	= data->acdirmax;
1123 		ctx->need_mount	= false;
1124 
1125 		if (!is_remount_fc(fc)) {
1126 			memcpy(sap, &data->addr, sizeof(data->addr));
1127 			ctx->nfs_server.addrlen = sizeof(data->addr);
1128 			ctx->nfs_server.port = ntohs(data->addr.sin_port);
1129 		}
1130 
1131 		if (sap->ss_family != AF_INET ||
1132 		    !nfs_verify_server_address(sap))
1133 			goto out_no_address;
1134 
1135 		if (!(data->flags & NFS_MOUNT_TCP))
1136 			ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
1137 		/* N.B. caller will free nfs_server.hostname in all cases */
1138 		ctx->nfs_server.hostname = kstrdup(data->hostname, GFP_KERNEL);
1139 		if (!ctx->nfs_server.hostname)
1140 			goto out_nomem;
1141 
1142 		ctx->namlen		= data->namlen;
1143 		ctx->bsize		= data->bsize;
1144 
1145 		if (data->flags & NFS_MOUNT_SECFLAVOUR)
1146 			ctx->selected_flavor = data->pseudoflavor;
1147 		else
1148 			ctx->selected_flavor = RPC_AUTH_UNIX;
1149 
1150 		if (!(data->flags & NFS_MOUNT_NONLM))
1151 			ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK|
1152 					 NFS_MOUNT_LOCAL_FCNTL);
1153 		else
1154 			ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK|
1155 					NFS_MOUNT_LOCAL_FCNTL);
1156 
1157 		/*
1158 		 * The legacy version 6 binary mount data from userspace has a
1159 		 * field used only to transport selinux information into the
1160 		 * kernel.  To continue to support that functionality we
1161 		 * have a touch of selinux knowledge here in the NFS code. The
1162 		 * userspace code converted context=blah to just blah so we are
1163 		 * converting back to the full string selinux understands.
1164 		 */
1165 		if (data->context[0]){
1166 #ifdef CONFIG_SECURITY_SELINUX
1167 			int ret;
1168 
1169 			data->context[NFS_MAX_CONTEXT_LEN] = '\0';
1170 			ret = vfs_parse_fs_string(fc, "context",
1171 						  data->context, strlen(data->context));
1172 			if (ret < 0)
1173 				return ret;
1174 #else
1175 			return -EINVAL;
1176 #endif
1177 		}
1178 
1179 		break;
1180 	default:
1181 		goto generic;
1182 	}
1183 
1184 	ret = nfs_validate_transport_protocol(fc, ctx);
1185 	if (ret)
1186 		return ret;
1187 
1188 	ctx->skip_reconfig_option_check = true;
1189 	return 0;
1190 
1191 generic:
1192 	return generic_parse_monolithic(fc, data);
1193 
1194 out_no_data:
1195 	if (is_remount_fc(fc)) {
1196 		ctx->skip_reconfig_option_check = true;
1197 		return 0;
1198 	}
1199 	return nfs_invalf(fc, "NFS: mount program didn't pass any mount data");
1200 
1201 out_no_v3:
1202 	return nfs_invalf(fc, "NFS: nfs_mount_data version does not support v3");
1203 
1204 out_no_sec:
1205 	return nfs_invalf(fc, "NFS: nfs_mount_data version supports only AUTH_SYS");
1206 
1207 out_nomem:
1208 	return -ENOMEM;
1209 
1210 out_no_address:
1211 	return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1212 
1213 out_invalid_fh:
1214 	return nfs_invalf(fc, "NFS: invalid root filehandle");
1215 
1216 out_invalid_data:
1217 	return nfs_invalf(fc, "NFS: invalid binary mount data");
1218 }
1219 
1220 #if IS_ENABLED(CONFIG_NFS_V4)
1221 struct compat_nfs_string {
1222 	compat_uint_t len;
1223 	compat_uptr_t data;
1224 };
1225 
1226 static inline void compat_nfs_string(struct nfs_string *dst,
1227 				     struct compat_nfs_string *src)
1228 {
1229 	dst->data = compat_ptr(src->data);
1230 	dst->len = src->len;
1231 }
1232 
1233 struct compat_nfs4_mount_data_v1 {
1234 	compat_int_t version;
1235 	compat_int_t flags;
1236 	compat_int_t rsize;
1237 	compat_int_t wsize;
1238 	compat_int_t timeo;
1239 	compat_int_t retrans;
1240 	compat_int_t acregmin;
1241 	compat_int_t acregmax;
1242 	compat_int_t acdirmin;
1243 	compat_int_t acdirmax;
1244 	struct compat_nfs_string client_addr;
1245 	struct compat_nfs_string mnt_path;
1246 	struct compat_nfs_string hostname;
1247 	compat_uint_t host_addrlen;
1248 	compat_uptr_t host_addr;
1249 	compat_int_t proto;
1250 	compat_int_t auth_flavourlen;
1251 	compat_uptr_t auth_flavours;
1252 };
1253 
1254 static void nfs4_compat_mount_data_conv(struct nfs4_mount_data *data)
1255 {
1256 	struct compat_nfs4_mount_data_v1 *compat =
1257 			(struct compat_nfs4_mount_data_v1 *)data;
1258 
1259 	/* copy the fields backwards */
1260 	data->auth_flavours = compat_ptr(compat->auth_flavours);
1261 	data->auth_flavourlen = compat->auth_flavourlen;
1262 	data->proto = compat->proto;
1263 	data->host_addr = compat_ptr(compat->host_addr);
1264 	data->host_addrlen = compat->host_addrlen;
1265 	compat_nfs_string(&data->hostname, &compat->hostname);
1266 	compat_nfs_string(&data->mnt_path, &compat->mnt_path);
1267 	compat_nfs_string(&data->client_addr, &compat->client_addr);
1268 	data->acdirmax = compat->acdirmax;
1269 	data->acdirmin = compat->acdirmin;
1270 	data->acregmax = compat->acregmax;
1271 	data->acregmin = compat->acregmin;
1272 	data->retrans = compat->retrans;
1273 	data->timeo = compat->timeo;
1274 	data->wsize = compat->wsize;
1275 	data->rsize = compat->rsize;
1276 	data->flags = compat->flags;
1277 	data->version = compat->version;
1278 }
1279 
1280 /*
1281  * Validate NFSv4 mount options
1282  */
1283 static int nfs4_parse_monolithic(struct fs_context *fc,
1284 				 struct nfs4_mount_data *data)
1285 {
1286 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1287 	struct sockaddr_storage *sap = &ctx->nfs_server._address;
1288 	int ret;
1289 	char *c;
1290 
1291 	if (!data) {
1292 		if (is_remount_fc(fc))
1293 			goto done;
1294 		return nfs_invalf(fc,
1295 			"NFS4: mount program didn't pass any mount data");
1296 	}
1297 
1298 	ctx->version = 4;
1299 
1300 	if (data->version != 1)
1301 		return generic_parse_monolithic(fc, data);
1302 
1303 	if (in_compat_syscall())
1304 		nfs4_compat_mount_data_conv(data);
1305 
1306 	if (data->host_addrlen > sizeof(ctx->nfs_server.address))
1307 		goto out_no_address;
1308 	if (data->host_addrlen == 0)
1309 		goto out_no_address;
1310 	ctx->nfs_server.addrlen = data->host_addrlen;
1311 	if (copy_from_user(sap, data->host_addr, data->host_addrlen))
1312 		return -EFAULT;
1313 	if (!nfs_verify_server_address(sap))
1314 		goto out_no_address;
1315 	ctx->nfs_server.port = ntohs(((struct sockaddr_in *)sap)->sin_port);
1316 
1317 	if (data->auth_flavourlen) {
1318 		rpc_authflavor_t pseudoflavor;
1319 
1320 		if (data->auth_flavourlen > 1)
1321 			goto out_inval_auth;
1322 		if (copy_from_user(&pseudoflavor, data->auth_flavours,
1323 				   sizeof(pseudoflavor)))
1324 			return -EFAULT;
1325 		ctx->selected_flavor = pseudoflavor;
1326 	} else {
1327 		ctx->selected_flavor = RPC_AUTH_UNIX;
1328 	}
1329 
1330 	c = strndup_user(data->hostname.data, NFS4_MAXNAMLEN);
1331 	if (IS_ERR(c))
1332 		return PTR_ERR(c);
1333 	ctx->nfs_server.hostname = c;
1334 
1335 	c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
1336 	if (IS_ERR(c))
1337 		return PTR_ERR(c);
1338 	ctx->nfs_server.export_path = c;
1339 	trace_nfs_mount_path(c);
1340 
1341 	c = strndup_user(data->client_addr.data, 16);
1342 	if (IS_ERR(c))
1343 		return PTR_ERR(c);
1344 	ctx->client_address = c;
1345 
1346 	/*
1347 	 * Translate to nfs_fs_context, which nfs_fill_super
1348 	 * can deal with.
1349 	 */
1350 
1351 	ctx->flags	= data->flags & NFS4_MOUNT_FLAGMASK;
1352 	ctx->rsize	= data->rsize;
1353 	ctx->wsize	= data->wsize;
1354 	ctx->timeo	= data->timeo;
1355 	ctx->retrans	= data->retrans;
1356 	ctx->acregmin	= data->acregmin;
1357 	ctx->acregmax	= data->acregmax;
1358 	ctx->acdirmin	= data->acdirmin;
1359 	ctx->acdirmax	= data->acdirmax;
1360 	ctx->nfs_server.protocol = data->proto;
1361 	ret = nfs_validate_transport_protocol(fc, ctx);
1362 	if (ret)
1363 		return ret;
1364 done:
1365 	ctx->skip_reconfig_option_check = true;
1366 	return 0;
1367 
1368 out_inval_auth:
1369 	return nfs_invalf(fc, "NFS4: Invalid number of RPC auth flavours %d",
1370 		      data->auth_flavourlen);
1371 
1372 out_no_address:
1373 	return nfs_invalf(fc, "NFS4: mount program didn't pass remote address");
1374 }
1375 #endif
1376 
1377 /*
1378  * Parse a monolithic block of data from sys_mount().
1379  */
1380 static int nfs_fs_context_parse_monolithic(struct fs_context *fc,
1381 					   void *data)
1382 {
1383 	if (fc->fs_type == &nfs_fs_type)
1384 		return nfs23_parse_monolithic(fc, data);
1385 
1386 #if IS_ENABLED(CONFIG_NFS_V4)
1387 	if (fc->fs_type == &nfs4_fs_type)
1388 		return nfs4_parse_monolithic(fc, data);
1389 #endif
1390 
1391 	return nfs_invalf(fc, "NFS: Unsupported monolithic data version");
1392 }
1393 
1394 /*
1395  * Validate the preparsed information in the config.
1396  */
1397 static int nfs_fs_context_validate(struct fs_context *fc)
1398 {
1399 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1400 	struct nfs_subversion *nfs_mod;
1401 	struct sockaddr_storage *sap = &ctx->nfs_server._address;
1402 	int max_namelen = PAGE_SIZE;
1403 	int max_pathlen = NFS_MAXPATHLEN;
1404 	int port = 0;
1405 	int ret;
1406 
1407 	if (!fc->source)
1408 		goto out_no_device_name;
1409 
1410 	/* Check for sanity first. */
1411 	if (ctx->minorversion && ctx->version != 4)
1412 		goto out_minorversion_mismatch;
1413 
1414 	if (ctx->options & NFS_OPTION_MIGRATION &&
1415 	    (ctx->version != 4 || ctx->minorversion != 0))
1416 		goto out_migration_misuse;
1417 
1418 	/* Verify that any proto=/mountproto= options match the address
1419 	 * families in the addr=/mountaddr= options.
1420 	 */
1421 	if (ctx->protofamily != AF_UNSPEC &&
1422 	    ctx->protofamily != ctx->nfs_server.address.sa_family)
1423 		goto out_proto_mismatch;
1424 
1425 	if (ctx->mountfamily != AF_UNSPEC) {
1426 		if (ctx->mount_server.addrlen) {
1427 			if (ctx->mountfamily != ctx->mount_server.address.sa_family)
1428 				goto out_mountproto_mismatch;
1429 		} else {
1430 			if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
1431 				goto out_mountproto_mismatch;
1432 		}
1433 	}
1434 
1435 	if (!nfs_verify_server_address(sap))
1436 		goto out_no_address;
1437 
1438 	ret = nfs_validate_transport_protocol(fc, ctx);
1439 	if (ret)
1440 		return ret;
1441 
1442 	if (ctx->version == 4) {
1443 		if (IS_ENABLED(CONFIG_NFS_V4)) {
1444 			if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1445 				port = NFS_RDMA_PORT;
1446 			else
1447 				port = NFS_PORT;
1448 			max_namelen = NFS4_MAXNAMLEN;
1449 			max_pathlen = NFS4_MAXPATHLEN;
1450 			ctx->flags &= ~(NFS_MOUNT_NONLM | NFS_MOUNT_NOACL |
1451 					NFS_MOUNT_VER3 | NFS_MOUNT_LOCAL_FLOCK |
1452 					NFS_MOUNT_LOCAL_FCNTL);
1453 		} else {
1454 			goto out_v4_not_compiled;
1455 		}
1456 	} else {
1457 		nfs_set_mount_transport_protocol(ctx);
1458 		if (ctx->nfs_server.protocol == XPRT_TRANSPORT_RDMA)
1459 			port = NFS_RDMA_PORT;
1460 	}
1461 
1462 	nfs_set_port(sap, &ctx->nfs_server.port, port);
1463 
1464 	ret = nfs_parse_source(fc, max_namelen, max_pathlen);
1465 	if (ret < 0)
1466 		return ret;
1467 
1468 	/* Load the NFS protocol module if we haven't done so yet */
1469 	if (!ctx->nfs_mod) {
1470 		nfs_mod = find_nfs_version(ctx->version);
1471 		if (IS_ERR(nfs_mod)) {
1472 			ret = PTR_ERR(nfs_mod);
1473 			goto out_version_unavailable;
1474 		}
1475 		ctx->nfs_mod = nfs_mod;
1476 	}
1477 
1478 	/* Ensure the filesystem context has the correct fs_type */
1479 	if (fc->fs_type != ctx->nfs_mod->nfs_fs) {
1480 		module_put(fc->fs_type->owner);
1481 		__module_get(ctx->nfs_mod->nfs_fs->owner);
1482 		fc->fs_type = ctx->nfs_mod->nfs_fs;
1483 	}
1484 	return 0;
1485 
1486 out_no_device_name:
1487 	return nfs_invalf(fc, "NFS: Device name not specified");
1488 out_v4_not_compiled:
1489 	nfs_errorf(fc, "NFS: NFSv4 is not compiled into kernel");
1490 	return -EPROTONOSUPPORT;
1491 out_no_address:
1492 	return nfs_invalf(fc, "NFS: mount program didn't pass remote address");
1493 out_mountproto_mismatch:
1494 	return nfs_invalf(fc, "NFS: Mount server address does not match mountproto= option");
1495 out_proto_mismatch:
1496 	return nfs_invalf(fc, "NFS: Server address does not match proto= option");
1497 out_minorversion_mismatch:
1498 	return nfs_invalf(fc, "NFS: Mount option vers=%u does not support minorversion=%u",
1499 			  ctx->version, ctx->minorversion);
1500 out_migration_misuse:
1501 	return nfs_invalf(fc, "NFS: 'Migration' not supported for this NFS version");
1502 out_version_unavailable:
1503 	nfs_errorf(fc, "NFS: Version unavailable");
1504 	return ret;
1505 }
1506 
1507 /*
1508  * Create an NFS superblock by the appropriate method.
1509  */
1510 static int nfs_get_tree(struct fs_context *fc)
1511 {
1512 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1513 	int err = nfs_fs_context_validate(fc);
1514 
1515 	if (err)
1516 		return err;
1517 	if (!ctx->internal)
1518 		return ctx->nfs_mod->rpc_ops->try_get_tree(fc);
1519 	else
1520 		return nfs_get_tree_common(fc);
1521 }
1522 
1523 /*
1524  * Handle duplication of a configuration.  The caller copied *src into *sc, but
1525  * it can't deal with resource pointers in the filesystem context, so we have
1526  * to do that.  We need to clear pointers, copy data or get extra refs as
1527  * appropriate.
1528  */
1529 static int nfs_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
1530 {
1531 	struct nfs_fs_context *src = nfs_fc2context(src_fc), *ctx;
1532 
1533 	ctx = kmemdup(src, sizeof(struct nfs_fs_context), GFP_KERNEL);
1534 	if (!ctx)
1535 		return -ENOMEM;
1536 
1537 	ctx->mntfh = nfs_alloc_fhandle();
1538 	if (!ctx->mntfh) {
1539 		kfree(ctx);
1540 		return -ENOMEM;
1541 	}
1542 	nfs_copy_fh(ctx->mntfh, src->mntfh);
1543 
1544 	get_nfs_version(ctx->nfs_mod);
1545 	ctx->client_address		= NULL;
1546 	ctx->mount_server.hostname	= NULL;
1547 	ctx->nfs_server.export_path	= NULL;
1548 	ctx->nfs_server.hostname	= NULL;
1549 	ctx->fscache_uniq		= NULL;
1550 	ctx->clone_data.fattr		= NULL;
1551 	fc->fs_private = ctx;
1552 	return 0;
1553 }
1554 
1555 static void nfs_fs_context_free(struct fs_context *fc)
1556 {
1557 	struct nfs_fs_context *ctx = nfs_fc2context(fc);
1558 
1559 	if (ctx) {
1560 		if (ctx->server)
1561 			nfs_free_server(ctx->server);
1562 		if (ctx->nfs_mod)
1563 			put_nfs_version(ctx->nfs_mod);
1564 		kfree(ctx->client_address);
1565 		kfree(ctx->mount_server.hostname);
1566 		kfree(ctx->nfs_server.export_path);
1567 		kfree(ctx->nfs_server.hostname);
1568 		kfree(ctx->fscache_uniq);
1569 		nfs_free_fhandle(ctx->mntfh);
1570 		nfs_free_fattr(ctx->clone_data.fattr);
1571 		kfree(ctx);
1572 	}
1573 }
1574 
1575 static const struct fs_context_operations nfs_fs_context_ops = {
1576 	.free			= nfs_fs_context_free,
1577 	.dup			= nfs_fs_context_dup,
1578 	.parse_param		= nfs_fs_context_parse_param,
1579 	.parse_monolithic	= nfs_fs_context_parse_monolithic,
1580 	.get_tree		= nfs_get_tree,
1581 	.reconfigure		= nfs_reconfigure,
1582 };
1583 
1584 /*
1585  * Prepare superblock configuration.  We use the namespaces attached to the
1586  * context.  This may be the current process's namespaces, or it may be a
1587  * container's namespaces.
1588  */
1589 static int nfs_init_fs_context(struct fs_context *fc)
1590 {
1591 	struct nfs_fs_context *ctx;
1592 
1593 	ctx = kzalloc(sizeof(struct nfs_fs_context), GFP_KERNEL);
1594 	if (unlikely(!ctx))
1595 		return -ENOMEM;
1596 
1597 	ctx->mntfh = nfs_alloc_fhandle();
1598 	if (unlikely(!ctx->mntfh)) {
1599 		kfree(ctx);
1600 		return -ENOMEM;
1601 	}
1602 
1603 	ctx->protofamily	= AF_UNSPEC;
1604 	ctx->mountfamily	= AF_UNSPEC;
1605 	ctx->mount_server.port	= NFS_UNSPEC_PORT;
1606 
1607 	if (fc->root) {
1608 		/* reconfigure, start with the current config */
1609 		struct nfs_server *nfss = fc->root->d_sb->s_fs_info;
1610 		struct net *net = nfss->nfs_client->cl_net;
1611 
1612 		ctx->flags		= nfss->flags;
1613 		ctx->rsize		= nfss->rsize;
1614 		ctx->wsize		= nfss->wsize;
1615 		ctx->retrans		= nfss->client->cl_timeout->to_retries;
1616 		ctx->selected_flavor	= nfss->client->cl_auth->au_flavor;
1617 		ctx->acregmin		= nfss->acregmin / HZ;
1618 		ctx->acregmax		= nfss->acregmax / HZ;
1619 		ctx->acdirmin		= nfss->acdirmin / HZ;
1620 		ctx->acdirmax		= nfss->acdirmax / HZ;
1621 		ctx->timeo		= 10U * nfss->client->cl_timeout->to_initval / HZ;
1622 		ctx->nfs_server.port	= nfss->port;
1623 		ctx->nfs_server.addrlen	= nfss->nfs_client->cl_addrlen;
1624 		ctx->version		= nfss->nfs_client->rpc_ops->version;
1625 		ctx->minorversion	= nfss->nfs_client->cl_minorversion;
1626 
1627 		memcpy(&ctx->nfs_server._address, &nfss->nfs_client->cl_addr,
1628 			ctx->nfs_server.addrlen);
1629 
1630 		if (fc->net_ns != net) {
1631 			put_net(fc->net_ns);
1632 			fc->net_ns = get_net(net);
1633 		}
1634 
1635 		ctx->nfs_mod = nfss->nfs_client->cl_nfs_mod;
1636 		get_nfs_version(ctx->nfs_mod);
1637 	} else {
1638 		/* defaults */
1639 		ctx->timeo		= NFS_UNSPEC_TIMEO;
1640 		ctx->retrans		= NFS_UNSPEC_RETRANS;
1641 		ctx->acregmin		= NFS_DEF_ACREGMIN;
1642 		ctx->acregmax		= NFS_DEF_ACREGMAX;
1643 		ctx->acdirmin		= NFS_DEF_ACDIRMIN;
1644 		ctx->acdirmax		= NFS_DEF_ACDIRMAX;
1645 		ctx->nfs_server.port	= NFS_UNSPEC_PORT;
1646 		ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
1647 		ctx->selected_flavor	= RPC_AUTH_MAXFLAVOR;
1648 		ctx->minorversion	= 0;
1649 		ctx->need_mount		= true;
1650 		ctx->xprtsec.policy	= RPC_XPRTSEC_NONE;
1651 		ctx->xprtsec.cert_serial	= TLS_NO_CERT;
1652 		ctx->xprtsec.privkey_serial	= TLS_NO_PRIVKEY;
1653 
1654 		fc->s_iflags		|= SB_I_STABLE_WRITES;
1655 	}
1656 	fc->fs_private = ctx;
1657 	fc->ops = &nfs_fs_context_ops;
1658 	return 0;
1659 }
1660 
1661 struct file_system_type nfs_fs_type = {
1662 	.owner			= THIS_MODULE,
1663 	.name			= "nfs",
1664 	.init_fs_context	= nfs_init_fs_context,
1665 	.parameters		= nfs_fs_parameters,
1666 	.kill_sb		= nfs_kill_super,
1667 	.fs_flags		= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1668 };
1669 MODULE_ALIAS_FS("nfs");
1670 EXPORT_SYMBOL_GPL(nfs_fs_type);
1671 
1672 #if IS_ENABLED(CONFIG_NFS_V4)
1673 struct file_system_type nfs4_fs_type = {
1674 	.owner			= THIS_MODULE,
1675 	.name			= "nfs4",
1676 	.init_fs_context	= nfs_init_fs_context,
1677 	.parameters		= nfs_fs_parameters,
1678 	.kill_sb		= nfs_kill_super,
1679 	.fs_flags		= FS_RENAME_DOES_D_MOVE|FS_BINARY_MOUNTDATA,
1680 };
1681 MODULE_ALIAS_FS("nfs4");
1682 MODULE_ALIAS("nfs4");
1683 EXPORT_SYMBOL_GPL(nfs4_fs_type);
1684 #endif /* CONFIG_NFS_V4 */
1685