xref: /linux/fs/smb/client/fs_context.c (revision a36e9f5cfe9eb3a1dce8769c7058251c42705357)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *   Copyright (C) 2020, Microsoft Corporation.
4  *
5  *   Author(s): Steve French <stfrench@microsoft.com>
6  *              David Howells <dhowells@redhat.com>
7  */
8 
9 /*
10 #include <linux/module.h>
11 #include <linux/nsproxy.h>
12 #include <linux/slab.h>
13 #include <linux/magic.h>
14 #include <linux/security.h>
15 #include <net/net_namespace.h>
16 #ifdef CONFIG_CIFS_DFS_UPCALL
17 #include "dfs_cache.h"
18 #endif
19 */
20 
21 #include <linux/ctype.h>
22 #include <linux/fs_context.h>
23 #include <linux/fs_parser.h>
24 #include <linux/fs.h>
25 #include <linux/mount.h>
26 #include <linux/parser.h>
27 #include <linux/utsname.h>
28 #include "cifsfs.h"
29 #include "cifspdu.h"
30 #include "cifsglob.h"
31 #include "cifsproto.h"
32 #include "cifs_unicode.h"
33 #include "cifs_debug.h"
34 #include "cifs_fs_sb.h"
35 #include "ntlmssp.h"
36 #include "nterr.h"
37 #include "rfc1002pdu.h"
38 #include "fs_context.h"
39 
40 DEFINE_MUTEX(cifs_mount_mutex);
41 
42 static const match_table_t cifs_smb_version_tokens = {
43 	{ Smb_1, SMB1_VERSION_STRING },
44 	{ Smb_20, SMB20_VERSION_STRING},
45 	{ Smb_21, SMB21_VERSION_STRING },
46 	{ Smb_30, SMB30_VERSION_STRING },
47 	{ Smb_302, SMB302_VERSION_STRING },
48 	{ Smb_302, ALT_SMB302_VERSION_STRING },
49 	{ Smb_311, SMB311_VERSION_STRING },
50 	{ Smb_311, ALT_SMB311_VERSION_STRING },
51 	{ Smb_3any, SMB3ANY_VERSION_STRING },
52 	{ Smb_default, SMBDEFAULT_VERSION_STRING },
53 	{ Smb_version_err, NULL }
54 };
55 
56 static const match_table_t cifs_secflavor_tokens = {
57 	{ Opt_sec_krb5, "krb5" },
58 	{ Opt_sec_krb5i, "krb5i" },
59 	{ Opt_sec_krb5p, "krb5p" },
60 	{ Opt_sec_ntlmsspi, "ntlmsspi" },
61 	{ Opt_sec_ntlmssp, "ntlmssp" },
62 	{ Opt_sec_ntlmv2, "nontlm" },
63 	{ Opt_sec_ntlmv2, "ntlmv2" },
64 	{ Opt_sec_ntlmv2i, "ntlmv2i" },
65 	{ Opt_sec_none, "none" },
66 
67 	{ Opt_sec_err, NULL }
68 };
69 
70 const struct fs_parameter_spec smb3_fs_parameters[] = {
71 	/* Mount options that take no arguments */
72 	fsparam_flag_no("user_xattr", Opt_user_xattr),
73 	fsparam_flag_no("forceuid", Opt_forceuid),
74 	fsparam_flag_no("multichannel", Opt_multichannel),
75 	fsparam_flag_no("forcegid", Opt_forcegid),
76 	fsparam_flag("noblocksend", Opt_noblocksend),
77 	fsparam_flag("noautotune", Opt_noautotune),
78 	fsparam_flag("nolease", Opt_nolease),
79 	fsparam_flag_no("hard", Opt_hard),
80 	fsparam_flag_no("soft", Opt_soft),
81 	fsparam_flag_no("perm", Opt_perm),
82 	fsparam_flag("nodelete", Opt_nodelete),
83 	fsparam_flag_no("mapposix", Opt_mapposix),
84 	fsparam_flag("mapchars", Opt_mapchars),
85 	fsparam_flag("nomapchars", Opt_nomapchars),
86 	fsparam_flag_no("sfu", Opt_sfu),
87 	fsparam_flag("nodfs", Opt_nodfs),
88 	fsparam_flag_no("posixpaths", Opt_posixpaths),
89 	fsparam_flag_no("unix", Opt_unix),
90 	fsparam_flag_no("linux", Opt_unix),
91 	fsparam_flag_no("posix", Opt_unix),
92 	fsparam_flag("nocase", Opt_nocase),
93 	fsparam_flag("ignorecase", Opt_nocase),
94 	fsparam_flag_no("brl", Opt_brl),
95 	fsparam_flag_no("handlecache", Opt_handlecache),
96 	fsparam_flag("forcemandatorylock", Opt_forcemandatorylock),
97 	fsparam_flag("forcemand", Opt_forcemandatorylock),
98 	fsparam_flag("setuidfromacl", Opt_setuidfromacl),
99 	fsparam_flag("idsfromsid", Opt_setuidfromacl),
100 	fsparam_flag_no("setuids", Opt_setuids),
101 	fsparam_flag_no("dynperm", Opt_dynperm),
102 	fsparam_flag_no("intr", Opt_intr),
103 	fsparam_flag_no("strictsync", Opt_strictsync),
104 	fsparam_flag_no("serverino", Opt_serverino),
105 	fsparam_flag("rwpidforward", Opt_rwpidforward),
106 	fsparam_flag("cifsacl", Opt_cifsacl),
107 	fsparam_flag_no("acl", Opt_acl),
108 	fsparam_flag("locallease", Opt_locallease),
109 	fsparam_flag("sign", Opt_sign),
110 	fsparam_flag("ignore_signature", Opt_ignore_signature),
111 	fsparam_flag("signloosely", Opt_ignore_signature),
112 	fsparam_flag("seal", Opt_seal),
113 	fsparam_flag("noac", Opt_noac),
114 	fsparam_flag("fsc", Opt_fsc),
115 	fsparam_flag("mfsymlinks", Opt_mfsymlinks),
116 	fsparam_flag("multiuser", Opt_multiuser),
117 	fsparam_flag("sloppy", Opt_sloppy),
118 	fsparam_flag("nosharesock", Opt_nosharesock),
119 	fsparam_flag_no("persistenthandles", Opt_persistent),
120 	fsparam_flag_no("resilienthandles", Opt_resilient),
121 	fsparam_flag_no("tcpnodelay", Opt_tcp_nodelay),
122 	fsparam_flag("nosparse", Opt_nosparse),
123 	fsparam_flag("domainauto", Opt_domainauto),
124 	fsparam_flag("rdma", Opt_rdma),
125 	fsparam_flag("modesid", Opt_modesid),
126 	fsparam_flag("modefromsid", Opt_modesid),
127 	fsparam_flag("rootfs", Opt_rootfs),
128 	fsparam_flag("compress", Opt_compress),
129 	fsparam_flag("witness", Opt_witness),
130 
131 	/* Mount options which take uid or gid */
132 	fsparam_uid("backupuid", Opt_backupuid),
133 	fsparam_gid("backupgid", Opt_backupgid),
134 	fsparam_uid("uid", Opt_uid),
135 	fsparam_uid("cruid", Opt_cruid),
136 	fsparam_gid("gid", Opt_gid),
137 
138 	/* Mount options which take numeric value */
139 	fsparam_u32("file_mode", Opt_file_mode),
140 	fsparam_u32("dirmode", Opt_dirmode),
141 	fsparam_u32("dir_mode", Opt_dirmode),
142 	fsparam_u32("port", Opt_port),
143 	fsparam_u32("min_enc_offload", Opt_min_enc_offload),
144 	fsparam_u32("retrans", Opt_retrans),
145 	fsparam_u32("esize", Opt_min_enc_offload),
146 	fsparam_u32("bsize", Opt_blocksize),
147 	fsparam_u32("rasize", Opt_rasize),
148 	fsparam_u32("rsize", Opt_rsize),
149 	fsparam_u32("wsize", Opt_wsize),
150 	fsparam_u32("actimeo", Opt_actimeo),
151 	fsparam_u32("acdirmax", Opt_acdirmax),
152 	fsparam_u32("acregmax", Opt_acregmax),
153 	fsparam_u32("closetimeo", Opt_closetimeo),
154 	fsparam_u32("echo_interval", Opt_echo_interval),
155 	fsparam_u32("max_credits", Opt_max_credits),
156 	fsparam_u32("max_cached_dirs", Opt_max_cached_dirs),
157 	fsparam_u32("handletimeout", Opt_handletimeout),
158 	fsparam_u64("snapshot", Opt_snapshot),
159 	fsparam_u32("max_channels", Opt_max_channels),
160 
161 	/* Mount options which take string value */
162 	fsparam_string("source", Opt_source),
163 	fsparam_string("user", Opt_user),
164 	fsparam_string("username", Opt_user),
165 	fsparam_string("pass", Opt_pass),
166 	fsparam_string("password", Opt_pass),
167 	fsparam_string("password2", Opt_pass2),
168 	fsparam_string("ip", Opt_ip),
169 	fsparam_string("addr", Opt_ip),
170 	fsparam_string("domain", Opt_domain),
171 	fsparam_string("dom", Opt_domain),
172 	fsparam_string("srcaddr", Opt_srcaddr),
173 	fsparam_string("iocharset", Opt_iocharset),
174 	fsparam_string("netbiosname", Opt_netbiosname),
175 	fsparam_string("servern", Opt_servern),
176 	fsparam_string("ver", Opt_ver),
177 	fsparam_string("vers", Opt_vers),
178 	fsparam_string("sec", Opt_sec),
179 	fsparam_string("cache", Opt_cache),
180 	fsparam_string("reparse", Opt_reparse),
181 
182 	/* Arguments that should be ignored */
183 	fsparam_flag("guest", Opt_ignore),
184 	fsparam_flag("noatime", Opt_ignore),
185 	fsparam_flag("relatime", Opt_ignore),
186 	fsparam_flag("_netdev", Opt_ignore),
187 	fsparam_flag_no("suid", Opt_ignore),
188 	fsparam_flag_no("exec", Opt_ignore),
189 	fsparam_flag_no("dev", Opt_ignore),
190 	fsparam_flag_no("mand", Opt_ignore),
191 	fsparam_flag_no("auto", Opt_ignore),
192 	fsparam_string("cred", Opt_ignore),
193 	fsparam_string("credentials", Opt_ignore),
194 	/*
195 	 * UNC and prefixpath is now extracted from Opt_source
196 	 * in the new mount API so we can just ignore them going forward.
197 	 */
198 	fsparam_string("unc", Opt_ignore),
199 	fsparam_string("prefixpath", Opt_ignore),
200 	{}
201 };
202 
203 static int
204 cifs_parse_security_flavors(struct fs_context *fc, char *value, struct smb3_fs_context *ctx)
205 {
206 
207 	substring_t args[MAX_OPT_ARGS];
208 
209 	/*
210 	 * With mount options, the last one should win. Reset any existing
211 	 * settings back to default.
212 	 */
213 	ctx->sectype = Unspecified;
214 	ctx->sign = false;
215 
216 	switch (match_token(value, cifs_secflavor_tokens, args)) {
217 	case Opt_sec_krb5p:
218 		cifs_errorf(fc, "sec=krb5p is not supported. Use sec=krb5,seal instead\n");
219 		return 1;
220 	case Opt_sec_krb5i:
221 		ctx->sign = true;
222 		fallthrough;
223 	case Opt_sec_krb5:
224 		ctx->sectype = Kerberos;
225 		break;
226 	case Opt_sec_ntlmsspi:
227 		ctx->sign = true;
228 		fallthrough;
229 	case Opt_sec_ntlmssp:
230 		ctx->sectype = RawNTLMSSP;
231 		break;
232 	case Opt_sec_ntlmv2i:
233 		ctx->sign = true;
234 		fallthrough;
235 	case Opt_sec_ntlmv2:
236 		ctx->sectype = NTLMv2;
237 		break;
238 	case Opt_sec_none:
239 		ctx->nullauth = 1;
240 		kfree(ctx->username);
241 		ctx->username = NULL;
242 		break;
243 	default:
244 		cifs_errorf(fc, "bad security option: %s\n", value);
245 		return 1;
246 	}
247 
248 	return 0;
249 }
250 
251 static const match_table_t cifs_cacheflavor_tokens = {
252 	{ Opt_cache_loose, "loose" },
253 	{ Opt_cache_strict, "strict" },
254 	{ Opt_cache_none, "none" },
255 	{ Opt_cache_ro, "ro" },
256 	{ Opt_cache_rw, "singleclient" },
257 	{ Opt_cache_err, NULL }
258 };
259 
260 static int
261 cifs_parse_cache_flavor(struct fs_context *fc, char *value, struct smb3_fs_context *ctx)
262 {
263 	substring_t args[MAX_OPT_ARGS];
264 
265 	switch (match_token(value, cifs_cacheflavor_tokens, args)) {
266 	case Opt_cache_loose:
267 		ctx->direct_io = false;
268 		ctx->strict_io = false;
269 		ctx->cache_ro = false;
270 		ctx->cache_rw = false;
271 		break;
272 	case Opt_cache_strict:
273 		ctx->direct_io = false;
274 		ctx->strict_io = true;
275 		ctx->cache_ro = false;
276 		ctx->cache_rw = false;
277 		break;
278 	case Opt_cache_none:
279 		ctx->direct_io = true;
280 		ctx->strict_io = false;
281 		ctx->cache_ro = false;
282 		ctx->cache_rw = false;
283 		break;
284 	case Opt_cache_ro:
285 		ctx->direct_io = false;
286 		ctx->strict_io = false;
287 		ctx->cache_ro = true;
288 		ctx->cache_rw = false;
289 		break;
290 	case Opt_cache_rw:
291 		ctx->direct_io = false;
292 		ctx->strict_io = false;
293 		ctx->cache_ro = false;
294 		ctx->cache_rw = true;
295 		break;
296 	default:
297 		cifs_errorf(fc, "bad cache= option: %s\n", value);
298 		return 1;
299 	}
300 	return 0;
301 }
302 
303 static const match_table_t reparse_flavor_tokens = {
304 	{ Opt_reparse_default,	"default" },
305 	{ Opt_reparse_nfs,	"nfs" },
306 	{ Opt_reparse_wsl,	"wsl" },
307 	{ Opt_reparse_err,	NULL },
308 };
309 
310 static int parse_reparse_flavor(struct fs_context *fc, char *value,
311 				struct smb3_fs_context *ctx)
312 {
313 	substring_t args[MAX_OPT_ARGS];
314 
315 	switch (match_token(value, reparse_flavor_tokens, args)) {
316 	case Opt_reparse_default:
317 		ctx->reparse_type = CIFS_REPARSE_TYPE_DEFAULT;
318 		break;
319 	case Opt_reparse_nfs:
320 		ctx->reparse_type = CIFS_REPARSE_TYPE_NFS;
321 		break;
322 	case Opt_reparse_wsl:
323 		ctx->reparse_type = CIFS_REPARSE_TYPE_WSL;
324 		break;
325 	default:
326 		cifs_errorf(fc, "bad reparse= option: %s\n", value);
327 		return 1;
328 	}
329 	return 0;
330 }
331 
332 #define DUP_CTX_STR(field)						\
333 do {									\
334 	if (ctx->field) {						\
335 		new_ctx->field = kstrdup(ctx->field, GFP_ATOMIC);	\
336 		if (new_ctx->field == NULL) {				\
337 			smb3_cleanup_fs_context_contents(new_ctx);	\
338 			return -ENOMEM;					\
339 		}							\
340 	}								\
341 } while (0)
342 
343 int
344 smb3_fs_context_dup(struct smb3_fs_context *new_ctx, struct smb3_fs_context *ctx)
345 {
346 	memcpy(new_ctx, ctx, sizeof(*ctx));
347 	new_ctx->prepath = NULL;
348 	new_ctx->nodename = NULL;
349 	new_ctx->username = NULL;
350 	new_ctx->password = NULL;
351 	new_ctx->password2 = NULL;
352 	new_ctx->server_hostname = NULL;
353 	new_ctx->domainname = NULL;
354 	new_ctx->UNC = NULL;
355 	new_ctx->source = NULL;
356 	new_ctx->iocharset = NULL;
357 	new_ctx->leaf_fullpath = NULL;
358 	/*
359 	 * Make sure to stay in sync with smb3_cleanup_fs_context_contents()
360 	 */
361 	DUP_CTX_STR(prepath);
362 	DUP_CTX_STR(username);
363 	DUP_CTX_STR(password);
364 	DUP_CTX_STR(password2);
365 	DUP_CTX_STR(server_hostname);
366 	DUP_CTX_STR(UNC);
367 	DUP_CTX_STR(source);
368 	DUP_CTX_STR(domainname);
369 	DUP_CTX_STR(nodename);
370 	DUP_CTX_STR(iocharset);
371 	DUP_CTX_STR(leaf_fullpath);
372 
373 	return 0;
374 }
375 
376 static int
377 cifs_parse_smb_version(struct fs_context *fc, char *value, struct smb3_fs_context *ctx, bool is_smb3)
378 {
379 	substring_t args[MAX_OPT_ARGS];
380 
381 	switch (match_token(value, cifs_smb_version_tokens, args)) {
382 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
383 	case Smb_1:
384 		if (disable_legacy_dialects) {
385 			cifs_errorf(fc, "mount with legacy dialect disabled\n");
386 			return 1;
387 		}
388 		if (is_smb3) {
389 			cifs_errorf(fc, "vers=1.0 (cifs) not permitted when mounting with smb3\n");
390 			return 1;
391 		}
392 		cifs_errorf(fc, "Use of the less secure dialect vers=1.0 is not recommended unless required for access to very old servers\n");
393 		ctx->ops = &smb1_operations;
394 		ctx->vals = &smb1_values;
395 		break;
396 	case Smb_20:
397 		if (disable_legacy_dialects) {
398 			cifs_errorf(fc, "mount with legacy dialect disabled\n");
399 			return 1;
400 		}
401 		if (is_smb3) {
402 			cifs_errorf(fc, "vers=2.0 not permitted when mounting with smb3\n");
403 			return 1;
404 		}
405 		ctx->ops = &smb20_operations;
406 		ctx->vals = &smb20_values;
407 		break;
408 #else
409 	case Smb_1:
410 		cifs_errorf(fc, "vers=1.0 (cifs) mount not permitted when legacy dialects disabled\n");
411 		return 1;
412 	case Smb_20:
413 		cifs_errorf(fc, "vers=2.0 mount not permitted when legacy dialects disabled\n");
414 		return 1;
415 #endif /* CIFS_ALLOW_INSECURE_LEGACY */
416 	case Smb_21:
417 		ctx->ops = &smb21_operations;
418 		ctx->vals = &smb21_values;
419 		break;
420 	case Smb_30:
421 		ctx->ops = &smb30_operations;
422 		ctx->vals = &smb30_values;
423 		break;
424 	case Smb_302:
425 		ctx->ops = &smb30_operations; /* currently identical with 3.0 */
426 		ctx->vals = &smb302_values;
427 		break;
428 	case Smb_311:
429 		ctx->ops = &smb311_operations;
430 		ctx->vals = &smb311_values;
431 		break;
432 	case Smb_3any:
433 		ctx->ops = &smb30_operations; /* currently identical with 3.0 */
434 		ctx->vals = &smb3any_values;
435 		break;
436 	case Smb_default:
437 		ctx->ops = &smb30_operations;
438 		ctx->vals = &smbdefault_values;
439 		break;
440 	default:
441 		cifs_errorf(fc, "Unknown vers= option specified: %s\n", value);
442 		return 1;
443 	}
444 	return 0;
445 }
446 
447 int smb3_parse_opt(const char *options, const char *key, char **val)
448 {
449 	int rc = -ENOENT;
450 	char *opts, *orig, *p;
451 
452 	orig = opts = kstrdup(options, GFP_KERNEL);
453 	if (!opts)
454 		return -ENOMEM;
455 
456 	while ((p = strsep(&opts, ","))) {
457 		char *nval;
458 
459 		if (!*p)
460 			continue;
461 		if (strncasecmp(p, key, strlen(key)))
462 			continue;
463 		nval = strchr(p, '=');
464 		if (nval) {
465 			if (nval == p)
466 				continue;
467 			*nval++ = 0;
468 			*val = kstrdup(nval, GFP_KERNEL);
469 			rc = !*val ? -ENOMEM : 0;
470 			goto out;
471 		}
472 	}
473 out:
474 	kfree(orig);
475 	return rc;
476 }
477 
478 /*
479  * Remove duplicate path delimiters. Windows is supposed to do that
480  * but there are some bugs that prevent rename from working if there are
481  * multiple delimiters.
482  *
483  * Return a sanitized duplicate of @path or NULL for empty prefix paths.
484  * Otherwise, return ERR_PTR.
485  *
486  * @gfp indicates the GFP_* flags for kstrdup.
487  * The caller is responsible for freeing the original.
488  */
489 #define IS_DELIM(c) ((c) == '/' || (c) == '\\')
490 char *cifs_sanitize_prepath(char *prepath, gfp_t gfp)
491 {
492 	char *cursor1 = prepath, *cursor2 = prepath;
493 	char *s;
494 
495 	/* skip all prepended delimiters */
496 	while (IS_DELIM(*cursor1))
497 		cursor1++;
498 
499 	/* copy the first letter */
500 	*cursor2 = *cursor1;
501 
502 	/* copy the remainder... */
503 	while (*(cursor1++)) {
504 		/* ... skipping all duplicated delimiters */
505 		if (IS_DELIM(*cursor1) && IS_DELIM(*cursor2))
506 			continue;
507 		*(++cursor2) = *cursor1;
508 	}
509 
510 	/* if the last character is a delimiter, skip it */
511 	if (IS_DELIM(*(cursor2 - 1)))
512 		cursor2--;
513 
514 	*cursor2 = '\0';
515 	if (!*prepath)
516 		return NULL;
517 	s = kstrdup(prepath, gfp);
518 	if (!s)
519 		return ERR_PTR(-ENOMEM);
520 	return s;
521 }
522 
523 /*
524  * Return full path based on the values of @ctx->{UNC,prepath}.
525  *
526  * It is assumed that both values were already parsed by smb3_parse_devname().
527  */
528 char *smb3_fs_context_fullpath(const struct smb3_fs_context *ctx, char dirsep)
529 {
530 	size_t ulen, plen;
531 	char *s;
532 
533 	ulen = strlen(ctx->UNC);
534 	plen = ctx->prepath ? strlen(ctx->prepath) + 1 : 0;
535 
536 	s = kmalloc(ulen + plen + 1, GFP_KERNEL);
537 	if (!s)
538 		return ERR_PTR(-ENOMEM);
539 	memcpy(s, ctx->UNC, ulen);
540 	if (plen) {
541 		s[ulen] = dirsep;
542 		memcpy(s + ulen + 1, ctx->prepath, plen);
543 	}
544 	s[ulen + plen] = '\0';
545 	convert_delimiter(s, dirsep);
546 	return s;
547 }
548 
549 /*
550  * Parse a devname into substrings and populate the ctx->UNC and ctx->prepath
551  * fields with the result. Returns 0 on success and an error otherwise
552  * (e.g. ENOMEM or EINVAL)
553  */
554 int
555 smb3_parse_devname(const char *devname, struct smb3_fs_context *ctx)
556 {
557 	char *pos;
558 	const char *delims = "/\\";
559 	size_t len;
560 	int rc;
561 
562 	if (unlikely(!devname || !*devname)) {
563 		cifs_dbg(VFS, "Device name not specified\n");
564 		return -EINVAL;
565 	}
566 
567 	/* make sure we have a valid UNC double delimiter prefix */
568 	len = strspn(devname, delims);
569 	if (len != 2)
570 		return -EINVAL;
571 
572 	/* find delimiter between host and sharename */
573 	pos = strpbrk(devname + 2, delims);
574 	if (!pos)
575 		return -EINVAL;
576 
577 	/* record the server hostname */
578 	kfree(ctx->server_hostname);
579 	ctx->server_hostname = kstrndup(devname + 2, pos - devname - 2, GFP_KERNEL);
580 	if (!ctx->server_hostname)
581 		return -ENOMEM;
582 
583 	/* skip past delimiter */
584 	++pos;
585 
586 	/* now go until next delimiter or end of string */
587 	len = strcspn(pos, delims);
588 	if (!len)
589 		return -EINVAL;
590 
591 	/* move "pos" up to delimiter or NULL */
592 	pos += len;
593 	kfree(ctx->UNC);
594 	ctx->UNC = kstrndup(devname, pos - devname, GFP_KERNEL);
595 	if (!ctx->UNC)
596 		return -ENOMEM;
597 
598 	convert_delimiter(ctx->UNC, '\\');
599 
600 	/* skip any delimiter */
601 	if (*pos == '/' || *pos == '\\')
602 		pos++;
603 
604 	kfree(ctx->prepath);
605 	ctx->prepath = NULL;
606 
607 	/* If pos is NULL then no prepath */
608 	if (!*pos)
609 		return 0;
610 
611 	ctx->prepath = cifs_sanitize_prepath(pos, GFP_KERNEL);
612 	if (IS_ERR(ctx->prepath)) {
613 		rc = PTR_ERR(ctx->prepath);
614 		ctx->prepath = NULL;
615 		return rc;
616 	}
617 
618 	return 0;
619 }
620 
621 static void smb3_fs_context_free(struct fs_context *fc);
622 static int smb3_fs_context_parse_param(struct fs_context *fc,
623 				       struct fs_parameter *param);
624 static int smb3_fs_context_parse_monolithic(struct fs_context *fc,
625 					    void *data);
626 static int smb3_get_tree(struct fs_context *fc);
627 static int smb3_reconfigure(struct fs_context *fc);
628 
629 static const struct fs_context_operations smb3_fs_context_ops = {
630 	.free			= smb3_fs_context_free,
631 	.parse_param		= smb3_fs_context_parse_param,
632 	.parse_monolithic	= smb3_fs_context_parse_monolithic,
633 	.get_tree		= smb3_get_tree,
634 	.reconfigure		= smb3_reconfigure,
635 };
636 
637 /*
638  * Parse a monolithic block of data from sys_mount().
639  * smb3_fs_context_parse_monolithic - Parse key[=val][,key[=val]]* mount data
640  * @ctx: The superblock configuration to fill in.
641  * @data: The data to parse
642  *
643  * Parse a blob of data that's in key[=val][,key[=val]]* form.  This can be
644  * called from the ->monolithic_mount_data() fs_context operation.
645  *
646  * Returns 0 on success or the error returned by the ->parse_option() fs_context
647  * operation on failure.
648  */
649 static int smb3_fs_context_parse_monolithic(struct fs_context *fc,
650 					   void *data)
651 {
652 	char *options = data, *key;
653 	int ret = 0;
654 
655 	if (!options)
656 		return 0;
657 
658 	ret = security_sb_eat_lsm_opts(options, &fc->security);
659 	if (ret)
660 		return ret;
661 
662 	/* BB Need to add support for sep= here TBD */
663 	while ((key = strsep(&options, ",")) != NULL) {
664 		size_t len;
665 		char *value;
666 
667 		if (*key == 0)
668 			break;
669 
670 		/* Check if following character is the deliminator If yes,
671 		 * we have encountered a double deliminator reset the NULL
672 		 * character to the deliminator
673 		 */
674 		while (options && options[0] == ',') {
675 			len = strlen(key);
676 			strcpy(key + len, options);
677 			options = strchr(options, ',');
678 			if (options)
679 				*options++ = 0;
680 		}
681 
682 
683 		len = 0;
684 		value = strchr(key, '=');
685 		if (value) {
686 			if (value == key)
687 				continue;
688 			*value++ = 0;
689 			len = strlen(value);
690 		}
691 
692 		ret = vfs_parse_fs_string(fc, key, value, len);
693 		if (ret < 0)
694 			break;
695 	}
696 
697 	return ret;
698 }
699 
700 /*
701  * Validate the preparsed information in the config.
702  */
703 static int smb3_fs_context_validate(struct fs_context *fc)
704 {
705 	struct smb3_fs_context *ctx = smb3_fc2context(fc);
706 
707 	if (ctx->rdma && ctx->vals->protocol_id < SMB30_PROT_ID) {
708 		cifs_errorf(fc, "SMB Direct requires Version >=3.0\n");
709 		return -EOPNOTSUPP;
710 	}
711 
712 #ifndef CONFIG_KEYS
713 	/* Muliuser mounts require CONFIG_KEYS support */
714 	if (ctx->multiuser) {
715 		cifs_errorf(fc, "Multiuser mounts require kernels with CONFIG_KEYS enabled\n");
716 		return -1;
717 	}
718 #endif
719 
720 	if (ctx->got_version == false)
721 		pr_warn_once("No dialect specified on mount. Default has changed to a more secure dialect, SMB2.1 or later (e.g. SMB3.1.1), from CIFS (SMB1). To use the less secure SMB1 dialect to access old servers which do not support SMB3.1.1 (or even SMB3 or SMB2.1) specify vers=1.0 on mount.\n");
722 
723 
724 	if (!ctx->UNC) {
725 		cifs_errorf(fc, "CIFS mount error: No usable UNC path provided in device string!\n");
726 		return -1;
727 	}
728 
729 	/* make sure UNC has a share name */
730 	if (strlen(ctx->UNC) < 3 || !strchr(ctx->UNC + 3, '\\')) {
731 		cifs_errorf(fc, "Malformed UNC. Unable to find share name.\n");
732 		return -ENOENT;
733 	}
734 
735 	if (!ctx->got_ip) {
736 		int len;
737 		const char *slash;
738 
739 		/* No ip= option specified? Try to get it from UNC */
740 		/* Use the address part of the UNC. */
741 		slash = strchr(&ctx->UNC[2], '\\');
742 		len = slash - &ctx->UNC[2];
743 		if (!cifs_convert_address((struct sockaddr *)&ctx->dstaddr,
744 					  &ctx->UNC[2], len)) {
745 			pr_err("Unable to determine destination address\n");
746 			return -EHOSTUNREACH;
747 		}
748 	}
749 
750 	/* set the port that we got earlier */
751 	cifs_set_port((struct sockaddr *)&ctx->dstaddr, ctx->port);
752 
753 	if (ctx->uid_specified && !ctx->forceuid_specified) {
754 		ctx->override_uid = 1;
755 		pr_notice("enabling forceuid mount option implicitly because uid= option is specified\n");
756 	}
757 
758 	if (ctx->gid_specified && !ctx->forcegid_specified) {
759 		ctx->override_gid = 1;
760 		pr_notice("enabling forcegid mount option implicitly because gid= option is specified\n");
761 	}
762 
763 	if (ctx->override_uid && !ctx->uid_specified) {
764 		ctx->override_uid = 0;
765 		pr_notice("ignoring forceuid mount option specified with no uid= option\n");
766 	}
767 
768 	if (ctx->override_gid && !ctx->gid_specified) {
769 		ctx->override_gid = 0;
770 		pr_notice("ignoring forcegid mount option specified with no gid= option\n");
771 	}
772 
773 	return 0;
774 }
775 
776 static int smb3_get_tree_common(struct fs_context *fc)
777 {
778 	struct smb3_fs_context *ctx = smb3_fc2context(fc);
779 	struct dentry *root;
780 	int rc = 0;
781 
782 	root = cifs_smb3_do_mount(fc->fs_type, 0, ctx);
783 	if (IS_ERR(root))
784 		return PTR_ERR(root);
785 
786 	fc->root = root;
787 
788 	return rc;
789 }
790 
791 /*
792  * Create an SMB3 superblock from the parameters passed.
793  */
794 static int smb3_get_tree(struct fs_context *fc)
795 {
796 	int err = smb3_fs_context_validate(fc);
797 	int ret;
798 
799 	if (err)
800 		return err;
801 	cifs_mount_lock();
802 	ret = smb3_get_tree_common(fc);
803 	cifs_mount_unlock();
804 	return ret;
805 }
806 
807 static void smb3_fs_context_free(struct fs_context *fc)
808 {
809 	struct smb3_fs_context *ctx = smb3_fc2context(fc);
810 
811 	smb3_cleanup_fs_context(ctx);
812 }
813 
814 /*
815  * Compare the old and new proposed context during reconfigure
816  * and check if the changes are compatible.
817  */
818 static int smb3_verify_reconfigure_ctx(struct fs_context *fc,
819 				       struct smb3_fs_context *new_ctx,
820 				       struct smb3_fs_context *old_ctx, bool need_recon)
821 {
822 	if (new_ctx->posix_paths != old_ctx->posix_paths) {
823 		cifs_errorf(fc, "can not change posixpaths during remount\n");
824 		return -EINVAL;
825 	}
826 	if (new_ctx->sectype != old_ctx->sectype) {
827 		cifs_errorf(fc, "can not change sec during remount\n");
828 		return -EINVAL;
829 	}
830 	if (new_ctx->multiuser != old_ctx->multiuser) {
831 		cifs_errorf(fc, "can not change multiuser during remount\n");
832 		return -EINVAL;
833 	}
834 	if (new_ctx->UNC &&
835 	    (!old_ctx->UNC || strcmp(new_ctx->UNC, old_ctx->UNC))) {
836 		cifs_errorf(fc, "can not change UNC during remount\n");
837 		return -EINVAL;
838 	}
839 	if (new_ctx->username &&
840 	    (!old_ctx->username || strcmp(new_ctx->username, old_ctx->username))) {
841 		cifs_errorf(fc, "can not change username during remount\n");
842 		return -EINVAL;
843 	}
844 	if (new_ctx->password &&
845 	    (!old_ctx->password || strcmp(new_ctx->password, old_ctx->password))) {
846 		if (need_recon == false) {
847 			cifs_errorf(fc,
848 				    "can not change password of active session during remount\n");
849 			return -EINVAL;
850 		} else if (old_ctx->sectype == Kerberos) {
851 			cifs_errorf(fc,
852 				    "can not change password for Kerberos via remount\n");
853 			return -EINVAL;
854 		}
855 	}
856 	if (new_ctx->domainname &&
857 	    (!old_ctx->domainname || strcmp(new_ctx->domainname, old_ctx->domainname))) {
858 		cifs_errorf(fc, "can not change domainname during remount\n");
859 		return -EINVAL;
860 	}
861 	if (strcmp(new_ctx->workstation_name, old_ctx->workstation_name)) {
862 		cifs_errorf(fc, "can not change workstation_name during remount\n");
863 		return -EINVAL;
864 	}
865 	if (new_ctx->nodename &&
866 	    (!old_ctx->nodename || strcmp(new_ctx->nodename, old_ctx->nodename))) {
867 		cifs_errorf(fc, "can not change nodename during remount\n");
868 		return -EINVAL;
869 	}
870 	if (new_ctx->iocharset &&
871 	    (!old_ctx->iocharset || strcmp(new_ctx->iocharset, old_ctx->iocharset))) {
872 		cifs_errorf(fc, "can not change iocharset during remount\n");
873 		return -EINVAL;
874 	}
875 
876 	return 0;
877 }
878 
879 #define STEAL_STRING(cifs_sb, ctx, field)				\
880 do {									\
881 	kfree(ctx->field);						\
882 	ctx->field = cifs_sb->ctx->field;				\
883 	cifs_sb->ctx->field = NULL;					\
884 } while (0)
885 
886 #define STEAL_STRING_SENSITIVE(cifs_sb, ctx, field)			\
887 do {									\
888 	kfree_sensitive(ctx->field);					\
889 	ctx->field = cifs_sb->ctx->field;				\
890 	cifs_sb->ctx->field = NULL;					\
891 } while (0)
892 
893 static int smb3_reconfigure(struct fs_context *fc)
894 {
895 	struct smb3_fs_context *ctx = smb3_fc2context(fc);
896 	struct dentry *root = fc->root;
897 	struct cifs_sb_info *cifs_sb = CIFS_SB(root->d_sb);
898 	struct cifs_ses *ses = cifs_sb_master_tcon(cifs_sb)->ses;
899 	bool need_recon = false;
900 	int rc;
901 
902 	if (ses->expired_pwd)
903 		need_recon = true;
904 
905 	rc = smb3_verify_reconfigure_ctx(fc, ctx, cifs_sb->ctx, need_recon);
906 	if (rc)
907 		return rc;
908 
909 	/*
910 	 * We can not change UNC/username/password/domainname/
911 	 * workstation_name/nodename/iocharset
912 	 * during reconnect so ignore what we have in the new context and
913 	 * just use what we already have in cifs_sb->ctx.
914 	 */
915 	STEAL_STRING(cifs_sb, ctx, UNC);
916 	STEAL_STRING(cifs_sb, ctx, source);
917 	STEAL_STRING(cifs_sb, ctx, username);
918 	if (need_recon == false)
919 		STEAL_STRING_SENSITIVE(cifs_sb, ctx, password);
920 	else  {
921 		kfree_sensitive(ses->password);
922 		ses->password = kstrdup(ctx->password, GFP_KERNEL);
923 		kfree_sensitive(ses->password2);
924 		ses->password2 = kstrdup(ctx->password2, GFP_KERNEL);
925 	}
926 	STEAL_STRING(cifs_sb, ctx, domainname);
927 	STEAL_STRING(cifs_sb, ctx, nodename);
928 	STEAL_STRING(cifs_sb, ctx, iocharset);
929 
930 	/* if rsize or wsize not passed in on remount, use previous values */
931 	if (ctx->rsize == 0)
932 		ctx->rsize = cifs_sb->ctx->rsize;
933 	if (ctx->wsize == 0)
934 		ctx->wsize = cifs_sb->ctx->wsize;
935 
936 
937 	smb3_cleanup_fs_context_contents(cifs_sb->ctx);
938 	rc = smb3_fs_context_dup(cifs_sb->ctx, ctx);
939 	smb3_update_mnt_flags(cifs_sb);
940 #ifdef CONFIG_CIFS_DFS_UPCALL
941 	if (!rc)
942 		rc = dfs_cache_remount_fs(cifs_sb);
943 #endif
944 
945 	return rc;
946 }
947 
948 static int smb3_fs_context_parse_param(struct fs_context *fc,
949 				      struct fs_parameter *param)
950 {
951 	struct fs_parse_result result;
952 	struct smb3_fs_context *ctx = smb3_fc2context(fc);
953 	int i, opt;
954 	bool is_smb3 = !strcmp(fc->fs_type->name, "smb3");
955 	bool skip_parsing = false;
956 
957 	cifs_dbg(FYI, "CIFS: parsing cifs mount option '%s'\n", param->key);
958 
959 	/*
960 	 * fs_parse can not handle string options with an empty value so
961 	 * we will need special handling of them.
962 	 */
963 	if (param->type == fs_value_is_string && param->string[0] == 0) {
964 		if (!strcmp("pass", param->key) || !strcmp("password", param->key)) {
965 			skip_parsing = true;
966 			opt = Opt_pass;
967 		} else if (!strcmp("user", param->key) || !strcmp("username", param->key)) {
968 			skip_parsing = true;
969 			opt = Opt_user;
970 		}
971 	}
972 
973 	if (!skip_parsing) {
974 		opt = fs_parse(fc, smb3_fs_parameters, param, &result);
975 		if (opt < 0)
976 			return ctx->sloppy ? 1 : opt;
977 	}
978 
979 	switch (opt) {
980 	case Opt_compress:
981 		ctx->compress = true;
982 		cifs_dbg(VFS,
983 			"SMB3 compression support is experimental\n");
984 		break;
985 	case Opt_nodfs:
986 		ctx->nodfs = 1;
987 		break;
988 	case Opt_hard:
989 		if (result.negated) {
990 			if (ctx->retry == 1)
991 				cifs_dbg(VFS, "conflicting hard vs. soft mount options\n");
992 			ctx->retry = 0;
993 		} else
994 			ctx->retry = 1;
995 		break;
996 	case Opt_soft:
997 		if (result.negated)
998 			ctx->retry = 1;
999 		else {
1000 			if (ctx->retry == 1)
1001 				cifs_dbg(VFS, "conflicting hard vs soft mount options\n");
1002 			ctx->retry = 0;
1003 		}
1004 		break;
1005 	case Opt_mapposix:
1006 		if (result.negated)
1007 			ctx->remap = false;
1008 		else {
1009 			ctx->remap = true;
1010 			ctx->sfu_remap = false; /* disable SFU mapping */
1011 		}
1012 		break;
1013 	case Opt_mapchars:
1014 		if (result.negated)
1015 			ctx->sfu_remap = false;
1016 		else {
1017 			ctx->sfu_remap = true;
1018 			ctx->remap = false; /* disable SFM (mapposix) mapping */
1019 		}
1020 		break;
1021 	case Opt_user_xattr:
1022 		if (result.negated)
1023 			ctx->no_xattr = 1;
1024 		else
1025 			ctx->no_xattr = 0;
1026 		break;
1027 	case Opt_forceuid:
1028 		if (result.negated)
1029 			ctx->override_uid = 0;
1030 		else
1031 			ctx->override_uid = 1;
1032 		ctx->forceuid_specified = true;
1033 		break;
1034 	case Opt_forcegid:
1035 		if (result.negated)
1036 			ctx->override_gid = 0;
1037 		else
1038 			ctx->override_gid = 1;
1039 		ctx->forcegid_specified = true;
1040 		break;
1041 	case Opt_perm:
1042 		if (result.negated)
1043 			ctx->noperm = 1;
1044 		else
1045 			ctx->noperm = 0;
1046 		break;
1047 	case Opt_dynperm:
1048 		if (result.negated)
1049 			ctx->dynperm = 0;
1050 		else
1051 			ctx->dynperm = 1;
1052 		break;
1053 	case Opt_sfu:
1054 		if (result.negated)
1055 			ctx->sfu_emul = 0;
1056 		else
1057 			ctx->sfu_emul = 1;
1058 		break;
1059 	case Opt_noblocksend:
1060 		ctx->noblocksnd = 1;
1061 		break;
1062 	case Opt_noautotune:
1063 		ctx->noautotune = 1;
1064 		break;
1065 	case Opt_nolease:
1066 		ctx->no_lease = 1;
1067 		break;
1068 	case Opt_nosparse:
1069 		ctx->no_sparse = 1;
1070 		break;
1071 	case Opt_nodelete:
1072 		ctx->nodelete = 1;
1073 		break;
1074 	case Opt_multichannel:
1075 		if (result.negated) {
1076 			ctx->multichannel = false;
1077 			ctx->max_channels = 1;
1078 		} else {
1079 			ctx->multichannel = true;
1080 			/* if number of channels not specified, default to 2 */
1081 			if (ctx->max_channels < 2)
1082 				ctx->max_channels = 2;
1083 		}
1084 		break;
1085 	case Opt_uid:
1086 		ctx->linux_uid = result.uid;
1087 		ctx->uid_specified = true;
1088 		break;
1089 	case Opt_cruid:
1090 		ctx->cred_uid = result.uid;
1091 		ctx->cruid_specified = true;
1092 		break;
1093 	case Opt_backupuid:
1094 		ctx->backupuid = result.uid;
1095 		ctx->backupuid_specified = true;
1096 		break;
1097 	case Opt_backupgid:
1098 		ctx->backupgid = result.gid;
1099 		ctx->backupgid_specified = true;
1100 		break;
1101 	case Opt_gid:
1102 		ctx->linux_gid = result.gid;
1103 		ctx->gid_specified = true;
1104 		break;
1105 	case Opt_port:
1106 		ctx->port = result.uint_32;
1107 		break;
1108 	case Opt_file_mode:
1109 		ctx->file_mode = result.uint_32;
1110 		break;
1111 	case Opt_dirmode:
1112 		ctx->dir_mode = result.uint_32;
1113 		break;
1114 	case Opt_min_enc_offload:
1115 		ctx->min_offload = result.uint_32;
1116 		break;
1117 	case Opt_retrans:
1118 		ctx->retrans = result.uint_32;
1119 		break;
1120 	case Opt_blocksize:
1121 		/*
1122 		 * inode blocksize realistically should never need to be
1123 		 * less than 16K or greater than 16M and default is 1MB.
1124 		 * Note that small inode block sizes (e.g. 64K) can lead
1125 		 * to very poor performance of common tools like cp and scp
1126 		 */
1127 		if ((result.uint_32 < CIFS_MAX_MSGSIZE) ||
1128 		   (result.uint_32 > (4 * SMB3_DEFAULT_IOSIZE))) {
1129 			cifs_errorf(fc, "%s: Invalid blocksize\n",
1130 				__func__);
1131 			goto cifs_parse_mount_err;
1132 		}
1133 		ctx->bsize = result.uint_32;
1134 		ctx->got_bsize = true;
1135 		break;
1136 	case Opt_rasize:
1137 		/*
1138 		 * readahead size realistically should never need to be
1139 		 * less than 1M (CIFS_DEFAULT_IOSIZE) or greater than 32M
1140 		 * (perhaps an exception should be considered in the
1141 		 * for the case of a large number of channels
1142 		 * when multichannel is negotiated) since that would lead
1143 		 * to plenty of parallel I/O in flight to the server.
1144 		 * Note that smaller read ahead sizes would
1145 		 * hurt performance of common tools like cp and scp
1146 		 * which often trigger sequential i/o with read ahead
1147 		 */
1148 		if ((result.uint_32 > (8 * SMB3_DEFAULT_IOSIZE)) ||
1149 		    (result.uint_32 < CIFS_DEFAULT_IOSIZE)) {
1150 			cifs_errorf(fc, "%s: Invalid rasize %d vs. %d\n",
1151 				__func__, result.uint_32, SMB3_DEFAULT_IOSIZE);
1152 			goto cifs_parse_mount_err;
1153 		}
1154 		ctx->rasize = result.uint_32;
1155 		break;
1156 	case Opt_rsize:
1157 		ctx->rsize = result.uint_32;
1158 		ctx->got_rsize = true;
1159 		break;
1160 	case Opt_wsize:
1161 		ctx->wsize = result.uint_32;
1162 		ctx->got_wsize = true;
1163 		if (ctx->wsize % PAGE_SIZE != 0) {
1164 			ctx->wsize = round_down(ctx->wsize, PAGE_SIZE);
1165 			if (ctx->wsize == 0) {
1166 				ctx->wsize = PAGE_SIZE;
1167 				cifs_dbg(VFS, "wsize too small, reset to minimum %ld\n", PAGE_SIZE);
1168 			} else {
1169 				cifs_dbg(VFS,
1170 					 "wsize rounded down to %d to multiple of PAGE_SIZE %ld\n",
1171 					 ctx->wsize, PAGE_SIZE);
1172 			}
1173 		}
1174 		break;
1175 	case Opt_acregmax:
1176 		ctx->acregmax = HZ * result.uint_32;
1177 		if (ctx->acregmax > CIFS_MAX_ACTIMEO) {
1178 			cifs_errorf(fc, "acregmax too large\n");
1179 			goto cifs_parse_mount_err;
1180 		}
1181 		break;
1182 	case Opt_acdirmax:
1183 		ctx->acdirmax = HZ * result.uint_32;
1184 		if (ctx->acdirmax > CIFS_MAX_ACTIMEO) {
1185 			cifs_errorf(fc, "acdirmax too large\n");
1186 			goto cifs_parse_mount_err;
1187 		}
1188 		break;
1189 	case Opt_actimeo:
1190 		if (HZ * result.uint_32 > CIFS_MAX_ACTIMEO) {
1191 			cifs_errorf(fc, "timeout too large\n");
1192 			goto cifs_parse_mount_err;
1193 		}
1194 		if ((ctx->acdirmax != CIFS_DEF_ACTIMEO) ||
1195 		    (ctx->acregmax != CIFS_DEF_ACTIMEO)) {
1196 			cifs_errorf(fc, "actimeo ignored since acregmax or acdirmax specified\n");
1197 			break;
1198 		}
1199 		ctx->acdirmax = ctx->acregmax = HZ * result.uint_32;
1200 		break;
1201 	case Opt_closetimeo:
1202 		ctx->closetimeo = HZ * result.uint_32;
1203 		if (ctx->closetimeo > SMB3_MAX_DCLOSETIMEO) {
1204 			cifs_errorf(fc, "closetimeo too large\n");
1205 			goto cifs_parse_mount_err;
1206 		}
1207 		break;
1208 	case Opt_echo_interval:
1209 		ctx->echo_interval = result.uint_32;
1210 		break;
1211 	case Opt_snapshot:
1212 		ctx->snapshot_time = result.uint_64;
1213 		break;
1214 	case Opt_max_credits:
1215 		if (result.uint_32 < 20 || result.uint_32 > 60000) {
1216 			cifs_errorf(fc, "%s: Invalid max_credits value\n",
1217 				 __func__);
1218 			goto cifs_parse_mount_err;
1219 		}
1220 		ctx->max_credits = result.uint_32;
1221 		break;
1222 	case Opt_max_channels:
1223 		if (result.uint_32 < 1 || result.uint_32 > CIFS_MAX_CHANNELS) {
1224 			cifs_errorf(fc, "%s: Invalid max_channels value, needs to be 1-%d\n",
1225 				 __func__, CIFS_MAX_CHANNELS);
1226 			goto cifs_parse_mount_err;
1227 		}
1228 		ctx->max_channels = result.uint_32;
1229 		/* If more than one channel requested ... they want multichan */
1230 		if (result.uint_32 > 1)
1231 			ctx->multichannel = true;
1232 		break;
1233 	case Opt_max_cached_dirs:
1234 		if (result.uint_32 < 1) {
1235 			cifs_errorf(fc, "%s: Invalid max_cached_dirs, needs to be 1 or more\n",
1236 				    __func__);
1237 			goto cifs_parse_mount_err;
1238 		}
1239 		ctx->max_cached_dirs = result.uint_32;
1240 		break;
1241 	case Opt_handletimeout:
1242 		ctx->handle_timeout = result.uint_32;
1243 		if (ctx->handle_timeout > SMB3_MAX_HANDLE_TIMEOUT) {
1244 			cifs_errorf(fc, "Invalid handle cache timeout, longer than 16 minutes\n");
1245 			goto cifs_parse_mount_err;
1246 		}
1247 		break;
1248 	case Opt_source:
1249 		kfree(ctx->UNC);
1250 		ctx->UNC = NULL;
1251 		switch (smb3_parse_devname(param->string, ctx)) {
1252 		case 0:
1253 			break;
1254 		case -ENOMEM:
1255 			cifs_errorf(fc, "Unable to allocate memory for devname\n");
1256 			goto cifs_parse_mount_err;
1257 		case -EINVAL:
1258 			cifs_errorf(fc, "Malformed UNC in devname\n");
1259 			goto cifs_parse_mount_err;
1260 		default:
1261 			cifs_errorf(fc, "Unknown error parsing devname\n");
1262 			goto cifs_parse_mount_err;
1263 		}
1264 		ctx->source = smb3_fs_context_fullpath(ctx, '/');
1265 		if (IS_ERR(ctx->source)) {
1266 			ctx->source = NULL;
1267 			cifs_errorf(fc, "OOM when copying UNC string\n");
1268 			goto cifs_parse_mount_err;
1269 		}
1270 		fc->source = kstrdup(ctx->source, GFP_KERNEL);
1271 		if (fc->source == NULL) {
1272 			cifs_errorf(fc, "OOM when copying UNC string\n");
1273 			goto cifs_parse_mount_err;
1274 		}
1275 		break;
1276 	case Opt_user:
1277 		kfree(ctx->username);
1278 		ctx->username = NULL;
1279 		if (ctx->nullauth)
1280 			break;
1281 		if (strlen(param->string) == 0) {
1282 			/* null user, ie. anonymous authentication */
1283 			ctx->nullauth = 1;
1284 			break;
1285 		}
1286 
1287 		if (strnlen(param->string, CIFS_MAX_USERNAME_LEN) >
1288 		    CIFS_MAX_USERNAME_LEN) {
1289 			pr_warn("username too long\n");
1290 			goto cifs_parse_mount_err;
1291 		}
1292 		ctx->username = kstrdup(param->string, GFP_KERNEL);
1293 		if (ctx->username == NULL) {
1294 			cifs_errorf(fc, "OOM when copying username string\n");
1295 			goto cifs_parse_mount_err;
1296 		}
1297 		break;
1298 	case Opt_pass:
1299 		kfree_sensitive(ctx->password);
1300 		ctx->password = NULL;
1301 		if (strlen(param->string) == 0)
1302 			break;
1303 
1304 		ctx->password = kstrdup(param->string, GFP_KERNEL);
1305 		if (ctx->password == NULL) {
1306 			cifs_errorf(fc, "OOM when copying password string\n");
1307 			goto cifs_parse_mount_err;
1308 		}
1309 		break;
1310 	case Opt_pass2:
1311 		kfree_sensitive(ctx->password2);
1312 		ctx->password2 = NULL;
1313 		if (strlen(param->string) == 0)
1314 			break;
1315 
1316 		ctx->password2 = kstrdup(param->string, GFP_KERNEL);
1317 		if (ctx->password2 == NULL) {
1318 			cifs_errorf(fc, "OOM when copying password2 string\n");
1319 			goto cifs_parse_mount_err;
1320 		}
1321 		break;
1322 	case Opt_ip:
1323 		if (strlen(param->string) == 0) {
1324 			ctx->got_ip = false;
1325 			break;
1326 		}
1327 		if (!cifs_convert_address((struct sockaddr *)&ctx->dstaddr,
1328 					  param->string,
1329 					  strlen(param->string))) {
1330 			pr_err("bad ip= option (%s)\n", param->string);
1331 			goto cifs_parse_mount_err;
1332 		}
1333 		ctx->got_ip = true;
1334 		break;
1335 	case Opt_domain:
1336 		if (strnlen(param->string, CIFS_MAX_DOMAINNAME_LEN)
1337 				== CIFS_MAX_DOMAINNAME_LEN) {
1338 			pr_warn("domain name too long\n");
1339 			goto cifs_parse_mount_err;
1340 		}
1341 
1342 		kfree(ctx->domainname);
1343 		ctx->domainname = kstrdup(param->string, GFP_KERNEL);
1344 		if (ctx->domainname == NULL) {
1345 			cifs_errorf(fc, "OOM when copying domainname string\n");
1346 			goto cifs_parse_mount_err;
1347 		}
1348 		cifs_dbg(FYI, "Domain name set\n");
1349 		break;
1350 	case Opt_srcaddr:
1351 		if (!cifs_convert_address(
1352 				(struct sockaddr *)&ctx->srcaddr,
1353 				param->string, strlen(param->string))) {
1354 			pr_warn("Could not parse srcaddr: %s\n",
1355 				param->string);
1356 			goto cifs_parse_mount_err;
1357 		}
1358 		break;
1359 	case Opt_iocharset:
1360 		if (strnlen(param->string, 1024) >= 65) {
1361 			pr_warn("iocharset name too long\n");
1362 			goto cifs_parse_mount_err;
1363 		}
1364 
1365 		if (strncasecmp(param->string, "default", 7) != 0) {
1366 			kfree(ctx->iocharset);
1367 			ctx->iocharset = kstrdup(param->string, GFP_KERNEL);
1368 			if (ctx->iocharset == NULL) {
1369 				cifs_errorf(fc, "OOM when copying iocharset string\n");
1370 				goto cifs_parse_mount_err;
1371 			}
1372 		}
1373 		/* if iocharset not set then load_nls_default
1374 		 * is used by caller
1375 		 */
1376 		cifs_dbg(FYI, "iocharset set to %s\n", ctx->iocharset);
1377 		break;
1378 	case Opt_netbiosname:
1379 		memset(ctx->source_rfc1001_name, 0x20,
1380 			RFC1001_NAME_LEN);
1381 		/*
1382 		 * FIXME: are there cases in which a comma can
1383 		 * be valid in workstation netbios name (and
1384 		 * need special handling)?
1385 		 */
1386 		for (i = 0; i < RFC1001_NAME_LEN; i++) {
1387 			/* don't ucase netbiosname for user */
1388 			if (param->string[i] == 0)
1389 				break;
1390 			ctx->source_rfc1001_name[i] = param->string[i];
1391 		}
1392 		/* The string has 16th byte zero still from
1393 		 * set at top of the function
1394 		 */
1395 		if (i == RFC1001_NAME_LEN && param->string[i] != 0)
1396 			pr_warn("netbiosname longer than 15 truncated\n");
1397 		break;
1398 	case Opt_servern:
1399 		/* last byte, type, is 0x20 for servr type */
1400 		memset(ctx->target_rfc1001_name, 0x20,
1401 			RFC1001_NAME_LEN_WITH_NULL);
1402 		/*
1403 		 * BB are there cases in which a comma can be valid in this
1404 		 * workstation netbios name (and need special handling)?
1405 		 */
1406 
1407 		/* user or mount helper must uppercase the netbios name */
1408 		for (i = 0; i < 15; i++) {
1409 			if (param->string[i] == 0)
1410 				break;
1411 			ctx->target_rfc1001_name[i] = param->string[i];
1412 		}
1413 
1414 		/* The string has 16th byte zero still from set at top of function */
1415 		if (i == RFC1001_NAME_LEN && param->string[i] != 0)
1416 			pr_warn("server netbiosname longer than 15 truncated\n");
1417 		break;
1418 	case Opt_ver:
1419 		/* version of mount userspace tools, not dialect */
1420 		/* If interface changes in mount.cifs bump to new ver */
1421 		if (strncasecmp(param->string, "1", 1) == 0) {
1422 			if (strlen(param->string) > 1) {
1423 				pr_warn("Bad mount helper ver=%s. Did you want SMB1 (CIFS) dialect and mean to type vers=1.0 instead?\n",
1424 					param->string);
1425 				goto cifs_parse_mount_err;
1426 			}
1427 			/* This is the default */
1428 			break;
1429 		}
1430 		/* For all other value, error */
1431 		pr_warn("Invalid mount helper version specified\n");
1432 		goto cifs_parse_mount_err;
1433 	case Opt_vers:
1434 		/* protocol version (dialect) */
1435 		if (cifs_parse_smb_version(fc, param->string, ctx, is_smb3) != 0)
1436 			goto cifs_parse_mount_err;
1437 		ctx->got_version = true;
1438 		break;
1439 	case Opt_sec:
1440 		if (cifs_parse_security_flavors(fc, param->string, ctx) != 0)
1441 			goto cifs_parse_mount_err;
1442 		break;
1443 	case Opt_cache:
1444 		if (cifs_parse_cache_flavor(fc, param->string, ctx) != 0)
1445 			goto cifs_parse_mount_err;
1446 		break;
1447 	case Opt_witness:
1448 #ifndef CONFIG_CIFS_SWN_UPCALL
1449 		cifs_errorf(fc, "Witness support needs CONFIG_CIFS_SWN_UPCALL config option\n");
1450 			goto cifs_parse_mount_err;
1451 #endif
1452 		ctx->witness = true;
1453 		pr_warn_once("Witness protocol support is experimental\n");
1454 		break;
1455 	case Opt_rootfs:
1456 #ifndef CONFIG_CIFS_ROOT
1457 		cifs_dbg(VFS, "rootfs support requires CONFIG_CIFS_ROOT config option\n");
1458 		goto cifs_parse_mount_err;
1459 #endif
1460 		ctx->rootfs = true;
1461 		break;
1462 	case Opt_posixpaths:
1463 		if (result.negated)
1464 			ctx->posix_paths = 0;
1465 		else
1466 			ctx->posix_paths = 1;
1467 		break;
1468 	case Opt_unix:
1469 		if (result.negated) {
1470 			if (ctx->linux_ext == 1)
1471 				pr_warn_once("conflicting posix mount options specified\n");
1472 			ctx->linux_ext = 0;
1473 			ctx->no_linux_ext = 1;
1474 		} else {
1475 			if (ctx->no_linux_ext == 1)
1476 				pr_warn_once("conflicting posix mount options specified\n");
1477 			ctx->linux_ext = 1;
1478 			ctx->no_linux_ext = 0;
1479 		}
1480 		break;
1481 	case Opt_nocase:
1482 		ctx->nocase = 1;
1483 		break;
1484 	case Opt_brl:
1485 		if (result.negated) {
1486 			/*
1487 			 * turn off mandatory locking in mode
1488 			 * if remote locking is turned off since the
1489 			 * local vfs will do advisory
1490 			 */
1491 			if (ctx->file_mode ==
1492 				(S_IALLUGO & ~(S_ISUID | S_IXGRP)))
1493 				ctx->file_mode = S_IALLUGO;
1494 			ctx->nobrl =  1;
1495 		} else
1496 			ctx->nobrl =  0;
1497 		break;
1498 	case Opt_handlecache:
1499 		if (result.negated)
1500 			ctx->nohandlecache = 1;
1501 		else
1502 			ctx->nohandlecache = 0;
1503 		break;
1504 	case Opt_forcemandatorylock:
1505 		ctx->mand_lock = 1;
1506 		break;
1507 	case Opt_setuids:
1508 		ctx->setuids = result.negated;
1509 		break;
1510 	case Opt_intr:
1511 		ctx->intr = !result.negated;
1512 		break;
1513 	case Opt_setuidfromacl:
1514 		ctx->setuidfromacl = 1;
1515 		break;
1516 	case Opt_strictsync:
1517 		ctx->nostrictsync = result.negated;
1518 		break;
1519 	case Opt_serverino:
1520 		ctx->server_ino = !result.negated;
1521 		break;
1522 	case Opt_rwpidforward:
1523 		ctx->rwpidforward = 1;
1524 		break;
1525 	case Opt_modesid:
1526 		ctx->mode_ace = 1;
1527 		break;
1528 	case Opt_cifsacl:
1529 		ctx->cifs_acl = !result.negated;
1530 		break;
1531 	case Opt_acl:
1532 		ctx->no_psx_acl = result.negated;
1533 		break;
1534 	case Opt_locallease:
1535 		ctx->local_lease = 1;
1536 		break;
1537 	case Opt_sign:
1538 		ctx->sign = true;
1539 		break;
1540 	case Opt_ignore_signature:
1541 		ctx->sign = true;
1542 		ctx->ignore_signature = true;
1543 		break;
1544 	case Opt_seal:
1545 		/* we do not do the following in secFlags because seal
1546 		 * is a per tree connection (mount) not a per socket
1547 		 * or per-smb connection option in the protocol
1548 		 * vol->secFlg |= CIFSSEC_MUST_SEAL;
1549 		 */
1550 		ctx->seal = 1;
1551 		break;
1552 	case Opt_noac:
1553 		pr_warn("Mount option noac not supported. Instead set /proc/fs/cifs/LookupCacheEnabled to 0\n");
1554 		break;
1555 	case Opt_fsc:
1556 #ifndef CONFIG_CIFS_FSCACHE
1557 		cifs_errorf(fc, "FS-Cache support needs CONFIG_CIFS_FSCACHE kernel config option set\n");
1558 		goto cifs_parse_mount_err;
1559 #endif
1560 		ctx->fsc = true;
1561 		break;
1562 	case Opt_mfsymlinks:
1563 		ctx->mfsymlinks = true;
1564 		break;
1565 	case Opt_multiuser:
1566 		ctx->multiuser = true;
1567 		break;
1568 	case Opt_sloppy:
1569 		ctx->sloppy = true;
1570 		break;
1571 	case Opt_nosharesock:
1572 		ctx->nosharesock = true;
1573 		break;
1574 	case Opt_persistent:
1575 		if (result.negated) {
1576 			ctx->nopersistent = true;
1577 			if (ctx->persistent) {
1578 				cifs_errorf(fc, "persistenthandles mount options conflict\n");
1579 				goto cifs_parse_mount_err;
1580 			}
1581 		} else {
1582 			ctx->persistent = true;
1583 			if ((ctx->nopersistent) || (ctx->resilient)) {
1584 				cifs_errorf(fc, "persistenthandles mount options conflict\n");
1585 				goto cifs_parse_mount_err;
1586 			}
1587 		}
1588 		break;
1589 	case Opt_resilient:
1590 		if (result.negated) {
1591 			ctx->resilient = false; /* already the default */
1592 		} else {
1593 			ctx->resilient = true;
1594 			if (ctx->persistent) {
1595 				cifs_errorf(fc, "persistenthandles mount options conflict\n");
1596 				goto cifs_parse_mount_err;
1597 			}
1598 		}
1599 		break;
1600 	case Opt_tcp_nodelay:
1601 		/* tcp nodelay should not usually be needed since we CORK/UNCORK the socket */
1602 		if (result.negated)
1603 			ctx->sockopt_tcp_nodelay = false;
1604 		else
1605 			ctx->sockopt_tcp_nodelay = true;
1606 		break;
1607 	case Opt_domainauto:
1608 		ctx->domainauto = true;
1609 		break;
1610 	case Opt_rdma:
1611 		ctx->rdma = true;
1612 		break;
1613 	case Opt_reparse:
1614 		if (parse_reparse_flavor(fc, param->string, ctx))
1615 			goto cifs_parse_mount_err;
1616 		break;
1617 	}
1618 	/* case Opt_ignore: - is ignored as expected ... */
1619 
1620 	return 0;
1621 
1622  cifs_parse_mount_err:
1623 	kfree_sensitive(ctx->password);
1624 	ctx->password = NULL;
1625 	kfree_sensitive(ctx->password2);
1626 	ctx->password2 = NULL;
1627 	return -EINVAL;
1628 }
1629 
1630 int smb3_init_fs_context(struct fs_context *fc)
1631 {
1632 	struct smb3_fs_context *ctx;
1633 	char *nodename = utsname()->nodename;
1634 	int i;
1635 
1636 	ctx = kzalloc(sizeof(struct smb3_fs_context), GFP_KERNEL);
1637 	if (unlikely(!ctx))
1638 		return -ENOMEM;
1639 
1640 	strscpy(ctx->workstation_name, nodename, sizeof(ctx->workstation_name));
1641 
1642 	/*
1643 	 * does not have to be perfect mapping since field is
1644 	 * informational, only used for servers that do not support
1645 	 * port 445 and it can be overridden at mount time
1646 	 */
1647 	memset(ctx->source_rfc1001_name, 0x20, RFC1001_NAME_LEN);
1648 	for (i = 0; i < strnlen(nodename, RFC1001_NAME_LEN); i++)
1649 		ctx->source_rfc1001_name[i] = toupper(nodename[i]);
1650 
1651 	ctx->source_rfc1001_name[RFC1001_NAME_LEN] = 0;
1652 	/*
1653 	 * null target name indicates to use *SMBSERVR default called name
1654 	 *  if we end up sending RFC1001 session initialize
1655 	 */
1656 	ctx->target_rfc1001_name[0] = 0;
1657 	ctx->cred_uid = current_uid();
1658 	ctx->linux_uid = current_uid();
1659 	ctx->linux_gid = current_gid();
1660 	/* By default 4MB read ahead size, 1MB block size */
1661 	ctx->bsize = CIFS_DEFAULT_IOSIZE; /* can improve cp performance significantly */
1662 	ctx->rasize = 0; /* 0 = use default (ie negotiated rsize) for read ahead pages */
1663 
1664 	/*
1665 	 * default to SFM style remapping of seven reserved characters
1666 	 * unless user overrides it or we negotiate CIFS POSIX where
1667 	 * it is unnecessary.  Can not simultaneously use more than one mapping
1668 	 * since then readdir could list files that open could not open
1669 	 */
1670 	ctx->remap = true;
1671 
1672 	/* default to only allowing write access to owner of the mount */
1673 	ctx->dir_mode = ctx->file_mode = S_IRUGO | S_IXUGO | S_IWUSR;
1674 
1675 	/* ctx->retry default is 0 (i.e. "soft" limited retry not hard retry) */
1676 	/* default is always to request posix paths. */
1677 	ctx->posix_paths = 1;
1678 	/* default to using server inode numbers where available */
1679 	ctx->server_ino = 1;
1680 
1681 	/* default is to use strict cifs caching semantics */
1682 	ctx->strict_io = true;
1683 
1684 	ctx->acregmax = CIFS_DEF_ACTIMEO;
1685 	ctx->acdirmax = CIFS_DEF_ACTIMEO;
1686 	ctx->closetimeo = SMB3_DEF_DCLOSETIMEO;
1687 	ctx->max_cached_dirs = MAX_CACHED_FIDS;
1688 	/* Most clients set timeout to 0, allows server to use its default */
1689 	ctx->handle_timeout = 0; /* See MS-SMB2 spec section 2.2.14.2.12 */
1690 
1691 	/* offer SMB2.1 and later (SMB3 etc). Secure and widely accepted */
1692 	ctx->ops = &smb30_operations;
1693 	ctx->vals = &smbdefault_values;
1694 
1695 	ctx->echo_interval = SMB_ECHO_INTERVAL_DEFAULT;
1696 
1697 	/* default to no multichannel (single server connection) */
1698 	ctx->multichannel = false;
1699 	ctx->max_channels = 1;
1700 
1701 	ctx->backupuid_specified = false; /* no backup intent for a user */
1702 	ctx->backupgid_specified = false; /* no backup intent for a group */
1703 
1704 	ctx->retrans = 1;
1705 	ctx->reparse_type = CIFS_REPARSE_TYPE_DEFAULT;
1706 
1707 /*
1708  *	short int override_uid = -1;
1709  *	short int override_gid = -1;
1710  *	char *nodename = strdup(utsname()->nodename);
1711  *	struct sockaddr *dstaddr = (struct sockaddr *)&vol->dstaddr;
1712  */
1713 
1714 	fc->fs_private = ctx;
1715 	fc->ops = &smb3_fs_context_ops;
1716 	return 0;
1717 }
1718 
1719 void
1720 smb3_cleanup_fs_context_contents(struct smb3_fs_context *ctx)
1721 {
1722 	if (ctx == NULL)
1723 		return;
1724 
1725 	/*
1726 	 * Make sure this stays in sync with smb3_fs_context_dup()
1727 	 */
1728 	kfree(ctx->username);
1729 	ctx->username = NULL;
1730 	kfree_sensitive(ctx->password);
1731 	ctx->password = NULL;
1732 	kfree_sensitive(ctx->password2);
1733 	ctx->password2 = NULL;
1734 	kfree(ctx->server_hostname);
1735 	ctx->server_hostname = NULL;
1736 	kfree(ctx->UNC);
1737 	ctx->UNC = NULL;
1738 	kfree(ctx->source);
1739 	ctx->source = NULL;
1740 	kfree(ctx->domainname);
1741 	ctx->domainname = NULL;
1742 	kfree(ctx->nodename);
1743 	ctx->nodename = NULL;
1744 	kfree(ctx->iocharset);
1745 	ctx->iocharset = NULL;
1746 	kfree(ctx->prepath);
1747 	ctx->prepath = NULL;
1748 	kfree(ctx->leaf_fullpath);
1749 	ctx->leaf_fullpath = NULL;
1750 }
1751 
1752 void
1753 smb3_cleanup_fs_context(struct smb3_fs_context *ctx)
1754 {
1755 	if (!ctx)
1756 		return;
1757 	smb3_cleanup_fs_context_contents(ctx);
1758 	kfree(ctx);
1759 }
1760 
1761 void smb3_update_mnt_flags(struct cifs_sb_info *cifs_sb)
1762 {
1763 	struct smb3_fs_context *ctx = cifs_sb->ctx;
1764 
1765 	if (ctx->nodfs)
1766 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_DFS;
1767 	else
1768 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NO_DFS;
1769 
1770 	if (ctx->noperm)
1771 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_PERM;
1772 	else
1773 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NO_PERM;
1774 
1775 	if (ctx->setuids)
1776 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_SET_UID;
1777 	else
1778 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SET_UID;
1779 
1780 	if (ctx->setuidfromacl)
1781 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_UID_FROM_ACL;
1782 	else
1783 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_UID_FROM_ACL;
1784 
1785 	if (ctx->server_ino)
1786 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_SERVER_INUM;
1787 	else
1788 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
1789 
1790 	if (ctx->remap)
1791 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MAP_SFM_CHR;
1792 	else
1793 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_MAP_SFM_CHR;
1794 
1795 	if (ctx->sfu_remap)
1796 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MAP_SPECIAL_CHR;
1797 	else
1798 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_MAP_SPECIAL_CHR;
1799 
1800 	if (ctx->no_xattr)
1801 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_XATTR;
1802 	else
1803 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NO_XATTR;
1804 
1805 	if (ctx->sfu_emul)
1806 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_UNX_EMUL;
1807 	else
1808 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_UNX_EMUL;
1809 
1810 	if (ctx->nobrl)
1811 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_BRL;
1812 	else
1813 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NO_BRL;
1814 
1815 	if (ctx->nohandlecache)
1816 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_HANDLE_CACHE;
1817 	else
1818 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NO_HANDLE_CACHE;
1819 
1820 	if (ctx->nostrictsync)
1821 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NOSSYNC;
1822 	else
1823 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NOSSYNC;
1824 
1825 	if (ctx->mand_lock)
1826 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NOPOSIXBRL;
1827 	else
1828 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NOPOSIXBRL;
1829 
1830 	if (ctx->rwpidforward)
1831 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RWPIDFORWARD;
1832 	else
1833 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_RWPIDFORWARD;
1834 
1835 	if (ctx->mode_ace)
1836 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MODE_FROM_SID;
1837 	else
1838 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_MODE_FROM_SID;
1839 
1840 	if (ctx->cifs_acl)
1841 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_CIFS_ACL;
1842 	else
1843 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_CIFS_ACL;
1844 
1845 	if (ctx->backupuid_specified)
1846 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_CIFS_BACKUPUID;
1847 	else
1848 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_CIFS_BACKUPUID;
1849 
1850 	if (ctx->backupgid_specified)
1851 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_CIFS_BACKUPGID;
1852 	else
1853 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_CIFS_BACKUPGID;
1854 
1855 	if (ctx->override_uid)
1856 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_UID;
1857 	else
1858 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_OVERR_UID;
1859 
1860 	if (ctx->override_gid)
1861 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_GID;
1862 	else
1863 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_OVERR_GID;
1864 
1865 	if (ctx->dynperm)
1866 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DYNPERM;
1867 	else
1868 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_DYNPERM;
1869 
1870 	if (ctx->fsc)
1871 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_FSCACHE;
1872 	else
1873 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_FSCACHE;
1874 
1875 	if (ctx->multiuser)
1876 		cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_MULTIUSER |
1877 					    CIFS_MOUNT_NO_PERM);
1878 	else
1879 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_MULTIUSER;
1880 
1881 
1882 	if (ctx->strict_io)
1883 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_STRICT_IO;
1884 	else
1885 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_STRICT_IO;
1886 
1887 	if (ctx->direct_io)
1888 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DIRECT_IO;
1889 	else
1890 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_DIRECT_IO;
1891 
1892 	if (ctx->mfsymlinks)
1893 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MF_SYMLINKS;
1894 	else
1895 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_MF_SYMLINKS;
1896 	if (ctx->mfsymlinks) {
1897 		if (ctx->sfu_emul) {
1898 			/*
1899 			 * Our SFU ("Services for Unix" emulation does not allow
1900 			 * creating symlinks but does allow reading existing SFU
1901 			 * symlinks (it does allow both creating and reading SFU
1902 			 * style mknod and FIFOs though). When "mfsymlinks" and
1903 			 * "sfu" are both enabled at the same time, it allows
1904 			 * reading both types of symlinks, but will only create
1905 			 * them with mfsymlinks format. This allows better
1906 			 * Apple compatibility (probably better for Samba too)
1907 			 * while still recognizing old Windows style symlinks.
1908 			 */
1909 			cifs_dbg(VFS, "mount options mfsymlinks and sfu both enabled\n");
1910 		}
1911 	}
1912 	cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SHUTDOWN;
1913 
1914 	return;
1915 }
1916