xref: /linux/fs/smb/client/fs_context.c (revision 7255fcc80d4b525cc10cfaaf7f485830d4ed2000)
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 numeric value */
132 	fsparam_u32("backupuid", Opt_backupuid),
133 	fsparam_u32("backupgid", Opt_backupgid),
134 	fsparam_u32("uid", Opt_uid),
135 	fsparam_u32("cruid", Opt_cruid),
136 	fsparam_u32("gid", Opt_gid),
137 	fsparam_u32("file_mode", Opt_file_mode),
138 	fsparam_u32("dirmode", Opt_dirmode),
139 	fsparam_u32("dir_mode", Opt_dirmode),
140 	fsparam_u32("port", Opt_port),
141 	fsparam_u32("min_enc_offload", Opt_min_enc_offload),
142 	fsparam_u32("retrans", Opt_retrans),
143 	fsparam_u32("esize", Opt_min_enc_offload),
144 	fsparam_u32("bsize", Opt_blocksize),
145 	fsparam_u32("rasize", Opt_rasize),
146 	fsparam_u32("rsize", Opt_rsize),
147 	fsparam_u32("wsize", Opt_wsize),
148 	fsparam_u32("actimeo", Opt_actimeo),
149 	fsparam_u32("acdirmax", Opt_acdirmax),
150 	fsparam_u32("acregmax", Opt_acregmax),
151 	fsparam_u32("closetimeo", Opt_closetimeo),
152 	fsparam_u32("echo_interval", Opt_echo_interval),
153 	fsparam_u32("max_credits", Opt_max_credits),
154 	fsparam_u32("max_cached_dirs", Opt_max_cached_dirs),
155 	fsparam_u32("handletimeout", Opt_handletimeout),
156 	fsparam_u64("snapshot", Opt_snapshot),
157 	fsparam_u32("max_channels", Opt_max_channels),
158 
159 	/* Mount options which take string value */
160 	fsparam_string("source", Opt_source),
161 	fsparam_string("user", Opt_user),
162 	fsparam_string("username", Opt_user),
163 	fsparam_string("pass", Opt_pass),
164 	fsparam_string("password", Opt_pass),
165 	fsparam_string("password2", Opt_pass2),
166 	fsparam_string("ip", Opt_ip),
167 	fsparam_string("addr", Opt_ip),
168 	fsparam_string("domain", Opt_domain),
169 	fsparam_string("dom", Opt_domain),
170 	fsparam_string("srcaddr", Opt_srcaddr),
171 	fsparam_string("iocharset", Opt_iocharset),
172 	fsparam_string("netbiosname", Opt_netbiosname),
173 	fsparam_string("servern", Opt_servern),
174 	fsparam_string("ver", Opt_ver),
175 	fsparam_string("vers", Opt_vers),
176 	fsparam_string("sec", Opt_sec),
177 	fsparam_string("cache", Opt_cache),
178 	fsparam_string("reparse", Opt_reparse),
179 
180 	/* Arguments that should be ignored */
181 	fsparam_flag("guest", Opt_ignore),
182 	fsparam_flag("noatime", Opt_ignore),
183 	fsparam_flag("relatime", Opt_ignore),
184 	fsparam_flag("_netdev", Opt_ignore),
185 	fsparam_flag_no("suid", Opt_ignore),
186 	fsparam_flag_no("exec", Opt_ignore),
187 	fsparam_flag_no("dev", Opt_ignore),
188 	fsparam_flag_no("mand", Opt_ignore),
189 	fsparam_flag_no("auto", Opt_ignore),
190 	fsparam_string("cred", Opt_ignore),
191 	fsparam_string("credentials", Opt_ignore),
192 	/*
193 	 * UNC and prefixpath is now extracted from Opt_source
194 	 * in the new mount API so we can just ignore them going forward.
195 	 */
196 	fsparam_string("unc", Opt_ignore),
197 	fsparam_string("prefixpath", Opt_ignore),
198 	{}
199 };
200 
201 static int
202 cifs_parse_security_flavors(struct fs_context *fc, char *value, struct smb3_fs_context *ctx)
203 {
204 
205 	substring_t args[MAX_OPT_ARGS];
206 
207 	/*
208 	 * With mount options, the last one should win. Reset any existing
209 	 * settings back to default.
210 	 */
211 	ctx->sectype = Unspecified;
212 	ctx->sign = false;
213 
214 	switch (match_token(value, cifs_secflavor_tokens, args)) {
215 	case Opt_sec_krb5p:
216 		cifs_errorf(fc, "sec=krb5p is not supported. Use sec=krb5,seal instead\n");
217 		return 1;
218 	case Opt_sec_krb5i:
219 		ctx->sign = true;
220 		fallthrough;
221 	case Opt_sec_krb5:
222 		ctx->sectype = Kerberos;
223 		break;
224 	case Opt_sec_ntlmsspi:
225 		ctx->sign = true;
226 		fallthrough;
227 	case Opt_sec_ntlmssp:
228 		ctx->sectype = RawNTLMSSP;
229 		break;
230 	case Opt_sec_ntlmv2i:
231 		ctx->sign = true;
232 		fallthrough;
233 	case Opt_sec_ntlmv2:
234 		ctx->sectype = NTLMv2;
235 		break;
236 	case Opt_sec_none:
237 		ctx->nullauth = 1;
238 		kfree(ctx->username);
239 		ctx->username = NULL;
240 		break;
241 	default:
242 		cifs_errorf(fc, "bad security option: %s\n", value);
243 		return 1;
244 	}
245 
246 	return 0;
247 }
248 
249 static const match_table_t cifs_cacheflavor_tokens = {
250 	{ Opt_cache_loose, "loose" },
251 	{ Opt_cache_strict, "strict" },
252 	{ Opt_cache_none, "none" },
253 	{ Opt_cache_ro, "ro" },
254 	{ Opt_cache_rw, "singleclient" },
255 	{ Opt_cache_err, NULL }
256 };
257 
258 static int
259 cifs_parse_cache_flavor(struct fs_context *fc, char *value, struct smb3_fs_context *ctx)
260 {
261 	substring_t args[MAX_OPT_ARGS];
262 
263 	switch (match_token(value, cifs_cacheflavor_tokens, args)) {
264 	case Opt_cache_loose:
265 		ctx->direct_io = false;
266 		ctx->strict_io = false;
267 		ctx->cache_ro = false;
268 		ctx->cache_rw = false;
269 		break;
270 	case Opt_cache_strict:
271 		ctx->direct_io = false;
272 		ctx->strict_io = true;
273 		ctx->cache_ro = false;
274 		ctx->cache_rw = false;
275 		break;
276 	case Opt_cache_none:
277 		ctx->direct_io = true;
278 		ctx->strict_io = false;
279 		ctx->cache_ro = false;
280 		ctx->cache_rw = false;
281 		break;
282 	case Opt_cache_ro:
283 		ctx->direct_io = false;
284 		ctx->strict_io = false;
285 		ctx->cache_ro = true;
286 		ctx->cache_rw = false;
287 		break;
288 	case Opt_cache_rw:
289 		ctx->direct_io = false;
290 		ctx->strict_io = false;
291 		ctx->cache_ro = false;
292 		ctx->cache_rw = true;
293 		break;
294 	default:
295 		cifs_errorf(fc, "bad cache= option: %s\n", value);
296 		return 1;
297 	}
298 	return 0;
299 }
300 
301 static const match_table_t reparse_flavor_tokens = {
302 	{ Opt_reparse_default,	"default" },
303 	{ Opt_reparse_nfs,	"nfs" },
304 	{ Opt_reparse_wsl,	"wsl" },
305 	{ Opt_reparse_err,	NULL },
306 };
307 
308 static int parse_reparse_flavor(struct fs_context *fc, char *value,
309 				struct smb3_fs_context *ctx)
310 {
311 	substring_t args[MAX_OPT_ARGS];
312 
313 	switch (match_token(value, reparse_flavor_tokens, args)) {
314 	case Opt_reparse_default:
315 		ctx->reparse_type = CIFS_REPARSE_TYPE_DEFAULT;
316 		break;
317 	case Opt_reparse_nfs:
318 		ctx->reparse_type = CIFS_REPARSE_TYPE_NFS;
319 		break;
320 	case Opt_reparse_wsl:
321 		ctx->reparse_type = CIFS_REPARSE_TYPE_WSL;
322 		break;
323 	default:
324 		cifs_errorf(fc, "bad reparse= option: %s\n", value);
325 		return 1;
326 	}
327 	return 0;
328 }
329 
330 #define DUP_CTX_STR(field)						\
331 do {									\
332 	if (ctx->field) {						\
333 		new_ctx->field = kstrdup(ctx->field, GFP_ATOMIC);	\
334 		if (new_ctx->field == NULL) {				\
335 			smb3_cleanup_fs_context_contents(new_ctx);	\
336 			return -ENOMEM;					\
337 		}							\
338 	}								\
339 } while (0)
340 
341 int
342 smb3_fs_context_dup(struct smb3_fs_context *new_ctx, struct smb3_fs_context *ctx)
343 {
344 	memcpy(new_ctx, ctx, sizeof(*ctx));
345 	new_ctx->prepath = NULL;
346 	new_ctx->nodename = NULL;
347 	new_ctx->username = NULL;
348 	new_ctx->password = NULL;
349 	new_ctx->password2 = NULL;
350 	new_ctx->server_hostname = NULL;
351 	new_ctx->domainname = NULL;
352 	new_ctx->UNC = NULL;
353 	new_ctx->source = NULL;
354 	new_ctx->iocharset = NULL;
355 	new_ctx->leaf_fullpath = NULL;
356 	/*
357 	 * Make sure to stay in sync with smb3_cleanup_fs_context_contents()
358 	 */
359 	DUP_CTX_STR(prepath);
360 	DUP_CTX_STR(username);
361 	DUP_CTX_STR(password);
362 	DUP_CTX_STR(password2);
363 	DUP_CTX_STR(server_hostname);
364 	DUP_CTX_STR(UNC);
365 	DUP_CTX_STR(source);
366 	DUP_CTX_STR(domainname);
367 	DUP_CTX_STR(nodename);
368 	DUP_CTX_STR(iocharset);
369 	DUP_CTX_STR(leaf_fullpath);
370 
371 	return 0;
372 }
373 
374 static int
375 cifs_parse_smb_version(struct fs_context *fc, char *value, struct smb3_fs_context *ctx, bool is_smb3)
376 {
377 	substring_t args[MAX_OPT_ARGS];
378 
379 	switch (match_token(value, cifs_smb_version_tokens, args)) {
380 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
381 	case Smb_1:
382 		if (disable_legacy_dialects) {
383 			cifs_errorf(fc, "mount with legacy dialect disabled\n");
384 			return 1;
385 		}
386 		if (is_smb3) {
387 			cifs_errorf(fc, "vers=1.0 (cifs) not permitted when mounting with smb3\n");
388 			return 1;
389 		}
390 		cifs_errorf(fc, "Use of the less secure dialect vers=1.0 is not recommended unless required for access to very old servers\n");
391 		ctx->ops = &smb1_operations;
392 		ctx->vals = &smb1_values;
393 		break;
394 	case Smb_20:
395 		if (disable_legacy_dialects) {
396 			cifs_errorf(fc, "mount with legacy dialect disabled\n");
397 			return 1;
398 		}
399 		if (is_smb3) {
400 			cifs_errorf(fc, "vers=2.0 not permitted when mounting with smb3\n");
401 			return 1;
402 		}
403 		ctx->ops = &smb20_operations;
404 		ctx->vals = &smb20_values;
405 		break;
406 #else
407 	case Smb_1:
408 		cifs_errorf(fc, "vers=1.0 (cifs) mount not permitted when legacy dialects disabled\n");
409 		return 1;
410 	case Smb_20:
411 		cifs_errorf(fc, "vers=2.0 mount not permitted when legacy dialects disabled\n");
412 		return 1;
413 #endif /* CIFS_ALLOW_INSECURE_LEGACY */
414 	case Smb_21:
415 		ctx->ops = &smb21_operations;
416 		ctx->vals = &smb21_values;
417 		break;
418 	case Smb_30:
419 		ctx->ops = &smb30_operations;
420 		ctx->vals = &smb30_values;
421 		break;
422 	case Smb_302:
423 		ctx->ops = &smb30_operations; /* currently identical with 3.0 */
424 		ctx->vals = &smb302_values;
425 		break;
426 	case Smb_311:
427 		ctx->ops = &smb311_operations;
428 		ctx->vals = &smb311_values;
429 		break;
430 	case Smb_3any:
431 		ctx->ops = &smb30_operations; /* currently identical with 3.0 */
432 		ctx->vals = &smb3any_values;
433 		break;
434 	case Smb_default:
435 		ctx->ops = &smb30_operations;
436 		ctx->vals = &smbdefault_values;
437 		break;
438 	default:
439 		cifs_errorf(fc, "Unknown vers= option specified: %s\n", value);
440 		return 1;
441 	}
442 	return 0;
443 }
444 
445 int smb3_parse_opt(const char *options, const char *key, char **val)
446 {
447 	int rc = -ENOENT;
448 	char *opts, *orig, *p;
449 
450 	orig = opts = kstrdup(options, GFP_KERNEL);
451 	if (!opts)
452 		return -ENOMEM;
453 
454 	while ((p = strsep(&opts, ","))) {
455 		char *nval;
456 
457 		if (!*p)
458 			continue;
459 		if (strncasecmp(p, key, strlen(key)))
460 			continue;
461 		nval = strchr(p, '=');
462 		if (nval) {
463 			if (nval == p)
464 				continue;
465 			*nval++ = 0;
466 			*val = kstrdup(nval, GFP_KERNEL);
467 			rc = !*val ? -ENOMEM : 0;
468 			goto out;
469 		}
470 	}
471 out:
472 	kfree(orig);
473 	return rc;
474 }
475 
476 /*
477  * Remove duplicate path delimiters. Windows is supposed to do that
478  * but there are some bugs that prevent rename from working if there are
479  * multiple delimiters.
480  *
481  * Return a sanitized duplicate of @path or NULL for empty prefix paths.
482  * Otherwise, return ERR_PTR.
483  *
484  * @gfp indicates the GFP_* flags for kstrdup.
485  * The caller is responsible for freeing the original.
486  */
487 #define IS_DELIM(c) ((c) == '/' || (c) == '\\')
488 char *cifs_sanitize_prepath(char *prepath, gfp_t gfp)
489 {
490 	char *cursor1 = prepath, *cursor2 = prepath;
491 	char *s;
492 
493 	/* skip all prepended delimiters */
494 	while (IS_DELIM(*cursor1))
495 		cursor1++;
496 
497 	/* copy the first letter */
498 	*cursor2 = *cursor1;
499 
500 	/* copy the remainder... */
501 	while (*(cursor1++)) {
502 		/* ... skipping all duplicated delimiters */
503 		if (IS_DELIM(*cursor1) && IS_DELIM(*cursor2))
504 			continue;
505 		*(++cursor2) = *cursor1;
506 	}
507 
508 	/* if the last character is a delimiter, skip it */
509 	if (IS_DELIM(*(cursor2 - 1)))
510 		cursor2--;
511 
512 	*cursor2 = '\0';
513 	if (!*prepath)
514 		return NULL;
515 	s = kstrdup(prepath, gfp);
516 	if (!s)
517 		return ERR_PTR(-ENOMEM);
518 	return s;
519 }
520 
521 /*
522  * Return full path based on the values of @ctx->{UNC,prepath}.
523  *
524  * It is assumed that both values were already parsed by smb3_parse_devname().
525  */
526 char *smb3_fs_context_fullpath(const struct smb3_fs_context *ctx, char dirsep)
527 {
528 	size_t ulen, plen;
529 	char *s;
530 
531 	ulen = strlen(ctx->UNC);
532 	plen = ctx->prepath ? strlen(ctx->prepath) + 1 : 0;
533 
534 	s = kmalloc(ulen + plen + 1, GFP_KERNEL);
535 	if (!s)
536 		return ERR_PTR(-ENOMEM);
537 	memcpy(s, ctx->UNC, ulen);
538 	if (plen) {
539 		s[ulen] = dirsep;
540 		memcpy(s + ulen + 1, ctx->prepath, plen);
541 	}
542 	s[ulen + plen] = '\0';
543 	convert_delimiter(s, dirsep);
544 	return s;
545 }
546 
547 /*
548  * Parse a devname into substrings and populate the ctx->UNC and ctx->prepath
549  * fields with the result. Returns 0 on success and an error otherwise
550  * (e.g. ENOMEM or EINVAL)
551  */
552 int
553 smb3_parse_devname(const char *devname, struct smb3_fs_context *ctx)
554 {
555 	char *pos;
556 	const char *delims = "/\\";
557 	size_t len;
558 	int rc;
559 
560 	if (unlikely(!devname || !*devname)) {
561 		cifs_dbg(VFS, "Device name not specified\n");
562 		return -EINVAL;
563 	}
564 
565 	/* make sure we have a valid UNC double delimiter prefix */
566 	len = strspn(devname, delims);
567 	if (len != 2)
568 		return -EINVAL;
569 
570 	/* find delimiter between host and sharename */
571 	pos = strpbrk(devname + 2, delims);
572 	if (!pos)
573 		return -EINVAL;
574 
575 	/* record the server hostname */
576 	kfree(ctx->server_hostname);
577 	ctx->server_hostname = kstrndup(devname + 2, pos - devname - 2, GFP_KERNEL);
578 	if (!ctx->server_hostname)
579 		return -ENOMEM;
580 
581 	/* skip past delimiter */
582 	++pos;
583 
584 	/* now go until next delimiter or end of string */
585 	len = strcspn(pos, delims);
586 	if (!len)
587 		return -EINVAL;
588 
589 	/* move "pos" up to delimiter or NULL */
590 	pos += len;
591 	kfree(ctx->UNC);
592 	ctx->UNC = kstrndup(devname, pos - devname, GFP_KERNEL);
593 	if (!ctx->UNC)
594 		return -ENOMEM;
595 
596 	convert_delimiter(ctx->UNC, '\\');
597 
598 	/* skip any delimiter */
599 	if (*pos == '/' || *pos == '\\')
600 		pos++;
601 
602 	kfree(ctx->prepath);
603 	ctx->prepath = NULL;
604 
605 	/* If pos is NULL then no prepath */
606 	if (!*pos)
607 		return 0;
608 
609 	ctx->prepath = cifs_sanitize_prepath(pos, GFP_KERNEL);
610 	if (IS_ERR(ctx->prepath)) {
611 		rc = PTR_ERR(ctx->prepath);
612 		ctx->prepath = NULL;
613 		return rc;
614 	}
615 
616 	return 0;
617 }
618 
619 static void smb3_fs_context_free(struct fs_context *fc);
620 static int smb3_fs_context_parse_param(struct fs_context *fc,
621 				       struct fs_parameter *param);
622 static int smb3_fs_context_parse_monolithic(struct fs_context *fc,
623 					    void *data);
624 static int smb3_get_tree(struct fs_context *fc);
625 static int smb3_reconfigure(struct fs_context *fc);
626 
627 static const struct fs_context_operations smb3_fs_context_ops = {
628 	.free			= smb3_fs_context_free,
629 	.parse_param		= smb3_fs_context_parse_param,
630 	.parse_monolithic	= smb3_fs_context_parse_monolithic,
631 	.get_tree		= smb3_get_tree,
632 	.reconfigure		= smb3_reconfigure,
633 };
634 
635 /*
636  * Parse a monolithic block of data from sys_mount().
637  * smb3_fs_context_parse_monolithic - Parse key[=val][,key[=val]]* mount data
638  * @ctx: The superblock configuration to fill in.
639  * @data: The data to parse
640  *
641  * Parse a blob of data that's in key[=val][,key[=val]]* form.  This can be
642  * called from the ->monolithic_mount_data() fs_context operation.
643  *
644  * Returns 0 on success or the error returned by the ->parse_option() fs_context
645  * operation on failure.
646  */
647 static int smb3_fs_context_parse_monolithic(struct fs_context *fc,
648 					   void *data)
649 {
650 	char *options = data, *key;
651 	int ret = 0;
652 
653 	if (!options)
654 		return 0;
655 
656 	ret = security_sb_eat_lsm_opts(options, &fc->security);
657 	if (ret)
658 		return ret;
659 
660 	/* BB Need to add support for sep= here TBD */
661 	while ((key = strsep(&options, ",")) != NULL) {
662 		size_t len;
663 		char *value;
664 
665 		if (*key == 0)
666 			break;
667 
668 		/* Check if following character is the deliminator If yes,
669 		 * we have encountered a double deliminator reset the NULL
670 		 * character to the deliminator
671 		 */
672 		while (options && options[0] == ',') {
673 			len = strlen(key);
674 			strcpy(key + len, options);
675 			options = strchr(options, ',');
676 			if (options)
677 				*options++ = 0;
678 		}
679 
680 
681 		len = 0;
682 		value = strchr(key, '=');
683 		if (value) {
684 			if (value == key)
685 				continue;
686 			*value++ = 0;
687 			len = strlen(value);
688 		}
689 
690 		ret = vfs_parse_fs_string(fc, key, value, len);
691 		if (ret < 0)
692 			break;
693 	}
694 
695 	return ret;
696 }
697 
698 /*
699  * Validate the preparsed information in the config.
700  */
701 static int smb3_fs_context_validate(struct fs_context *fc)
702 {
703 	struct smb3_fs_context *ctx = smb3_fc2context(fc);
704 
705 	if (ctx->rdma && ctx->vals->protocol_id < SMB30_PROT_ID) {
706 		cifs_errorf(fc, "SMB Direct requires Version >=3.0\n");
707 		return -EOPNOTSUPP;
708 	}
709 
710 #ifndef CONFIG_KEYS
711 	/* Muliuser mounts require CONFIG_KEYS support */
712 	if (ctx->multiuser) {
713 		cifs_errorf(fc, "Multiuser mounts require kernels with CONFIG_KEYS enabled\n");
714 		return -1;
715 	}
716 #endif
717 
718 	if (ctx->got_version == false)
719 		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");
720 
721 
722 	if (!ctx->UNC) {
723 		cifs_errorf(fc, "CIFS mount error: No usable UNC path provided in device string!\n");
724 		return -1;
725 	}
726 
727 	/* make sure UNC has a share name */
728 	if (strlen(ctx->UNC) < 3 || !strchr(ctx->UNC + 3, '\\')) {
729 		cifs_errorf(fc, "Malformed UNC. Unable to find share name.\n");
730 		return -ENOENT;
731 	}
732 
733 	if (!ctx->got_ip) {
734 		int len;
735 		const char *slash;
736 
737 		/* No ip= option specified? Try to get it from UNC */
738 		/* Use the address part of the UNC. */
739 		slash = strchr(&ctx->UNC[2], '\\');
740 		len = slash - &ctx->UNC[2];
741 		if (!cifs_convert_address((struct sockaddr *)&ctx->dstaddr,
742 					  &ctx->UNC[2], len)) {
743 			pr_err("Unable to determine destination address\n");
744 			return -EHOSTUNREACH;
745 		}
746 	}
747 
748 	/* set the port that we got earlier */
749 	cifs_set_port((struct sockaddr *)&ctx->dstaddr, ctx->port);
750 
751 	if (ctx->override_uid && !ctx->uid_specified) {
752 		ctx->override_uid = 0;
753 		pr_notice("ignoring forceuid mount option specified with no uid= option\n");
754 	}
755 
756 	if (ctx->override_gid && !ctx->gid_specified) {
757 		ctx->override_gid = 0;
758 		pr_notice("ignoring forcegid mount option specified with no gid= option\n");
759 	}
760 
761 	return 0;
762 }
763 
764 static int smb3_get_tree_common(struct fs_context *fc)
765 {
766 	struct smb3_fs_context *ctx = smb3_fc2context(fc);
767 	struct dentry *root;
768 	int rc = 0;
769 
770 	root = cifs_smb3_do_mount(fc->fs_type, 0, ctx);
771 	if (IS_ERR(root))
772 		return PTR_ERR(root);
773 
774 	fc->root = root;
775 
776 	return rc;
777 }
778 
779 /*
780  * Create an SMB3 superblock from the parameters passed.
781  */
782 static int smb3_get_tree(struct fs_context *fc)
783 {
784 	int err = smb3_fs_context_validate(fc);
785 	int ret;
786 
787 	if (err)
788 		return err;
789 	cifs_mount_lock();
790 	ret = smb3_get_tree_common(fc);
791 	cifs_mount_unlock();
792 	return ret;
793 }
794 
795 static void smb3_fs_context_free(struct fs_context *fc)
796 {
797 	struct smb3_fs_context *ctx = smb3_fc2context(fc);
798 
799 	smb3_cleanup_fs_context(ctx);
800 }
801 
802 /*
803  * Compare the old and new proposed context during reconfigure
804  * and check if the changes are compatible.
805  */
806 static int smb3_verify_reconfigure_ctx(struct fs_context *fc,
807 				       struct smb3_fs_context *new_ctx,
808 				       struct smb3_fs_context *old_ctx, bool need_recon)
809 {
810 	if (new_ctx->posix_paths != old_ctx->posix_paths) {
811 		cifs_errorf(fc, "can not change posixpaths during remount\n");
812 		return -EINVAL;
813 	}
814 	if (new_ctx->sectype != old_ctx->sectype) {
815 		cifs_errorf(fc, "can not change sec during remount\n");
816 		return -EINVAL;
817 	}
818 	if (new_ctx->multiuser != old_ctx->multiuser) {
819 		cifs_errorf(fc, "can not change multiuser during remount\n");
820 		return -EINVAL;
821 	}
822 	if (new_ctx->UNC &&
823 	    (!old_ctx->UNC || strcmp(new_ctx->UNC, old_ctx->UNC))) {
824 		cifs_errorf(fc, "can not change UNC during remount\n");
825 		return -EINVAL;
826 	}
827 	if (new_ctx->username &&
828 	    (!old_ctx->username || strcmp(new_ctx->username, old_ctx->username))) {
829 		cifs_errorf(fc, "can not change username during remount\n");
830 		return -EINVAL;
831 	}
832 	if (new_ctx->password &&
833 	    (!old_ctx->password || strcmp(new_ctx->password, old_ctx->password))) {
834 		if (need_recon == false) {
835 			cifs_errorf(fc,
836 				    "can not change password of active session during remount\n");
837 			return -EINVAL;
838 		} else if (old_ctx->sectype == Kerberos) {
839 			cifs_errorf(fc,
840 				    "can not change password for Kerberos via remount\n");
841 			return -EINVAL;
842 		}
843 	}
844 	if (new_ctx->domainname &&
845 	    (!old_ctx->domainname || strcmp(new_ctx->domainname, old_ctx->domainname))) {
846 		cifs_errorf(fc, "can not change domainname during remount\n");
847 		return -EINVAL;
848 	}
849 	if (strcmp(new_ctx->workstation_name, old_ctx->workstation_name)) {
850 		cifs_errorf(fc, "can not change workstation_name during remount\n");
851 		return -EINVAL;
852 	}
853 	if (new_ctx->nodename &&
854 	    (!old_ctx->nodename || strcmp(new_ctx->nodename, old_ctx->nodename))) {
855 		cifs_errorf(fc, "can not change nodename during remount\n");
856 		return -EINVAL;
857 	}
858 	if (new_ctx->iocharset &&
859 	    (!old_ctx->iocharset || strcmp(new_ctx->iocharset, old_ctx->iocharset))) {
860 		cifs_errorf(fc, "can not change iocharset during remount\n");
861 		return -EINVAL;
862 	}
863 
864 	return 0;
865 }
866 
867 #define STEAL_STRING(cifs_sb, ctx, field)				\
868 do {									\
869 	kfree(ctx->field);						\
870 	ctx->field = cifs_sb->ctx->field;				\
871 	cifs_sb->ctx->field = NULL;					\
872 } while (0)
873 
874 #define STEAL_STRING_SENSITIVE(cifs_sb, ctx, field)			\
875 do {									\
876 	kfree_sensitive(ctx->field);					\
877 	ctx->field = cifs_sb->ctx->field;				\
878 	cifs_sb->ctx->field = NULL;					\
879 } while (0)
880 
881 static int smb3_reconfigure(struct fs_context *fc)
882 {
883 	struct smb3_fs_context *ctx = smb3_fc2context(fc);
884 	struct dentry *root = fc->root;
885 	struct cifs_sb_info *cifs_sb = CIFS_SB(root->d_sb);
886 	struct cifs_ses *ses = cifs_sb_master_tcon(cifs_sb)->ses;
887 	bool need_recon = false;
888 	int rc;
889 
890 	if (ses->expired_pwd)
891 		need_recon = true;
892 
893 	rc = smb3_verify_reconfigure_ctx(fc, ctx, cifs_sb->ctx, need_recon);
894 	if (rc)
895 		return rc;
896 
897 	/*
898 	 * We can not change UNC/username/password/domainname/
899 	 * workstation_name/nodename/iocharset
900 	 * during reconnect so ignore what we have in the new context and
901 	 * just use what we already have in cifs_sb->ctx.
902 	 */
903 	STEAL_STRING(cifs_sb, ctx, UNC);
904 	STEAL_STRING(cifs_sb, ctx, source);
905 	STEAL_STRING(cifs_sb, ctx, username);
906 	if (need_recon == false)
907 		STEAL_STRING_SENSITIVE(cifs_sb, ctx, password);
908 	else  {
909 		kfree_sensitive(ses->password);
910 		ses->password = kstrdup(ctx->password, GFP_KERNEL);
911 		kfree_sensitive(ses->password2);
912 		ses->password2 = kstrdup(ctx->password2, GFP_KERNEL);
913 	}
914 	STEAL_STRING(cifs_sb, ctx, domainname);
915 	STEAL_STRING(cifs_sb, ctx, nodename);
916 	STEAL_STRING(cifs_sb, ctx, iocharset);
917 
918 	/* if rsize or wsize not passed in on remount, use previous values */
919 	if (ctx->rsize == 0)
920 		ctx->rsize = cifs_sb->ctx->rsize;
921 	if (ctx->wsize == 0)
922 		ctx->wsize = cifs_sb->ctx->wsize;
923 
924 
925 	smb3_cleanup_fs_context_contents(cifs_sb->ctx);
926 	rc = smb3_fs_context_dup(cifs_sb->ctx, ctx);
927 	smb3_update_mnt_flags(cifs_sb);
928 #ifdef CONFIG_CIFS_DFS_UPCALL
929 	if (!rc)
930 		rc = dfs_cache_remount_fs(cifs_sb);
931 #endif
932 
933 	return rc;
934 }
935 
936 static int smb3_fs_context_parse_param(struct fs_context *fc,
937 				      struct fs_parameter *param)
938 {
939 	struct fs_parse_result result;
940 	struct smb3_fs_context *ctx = smb3_fc2context(fc);
941 	int i, opt;
942 	bool is_smb3 = !strcmp(fc->fs_type->name, "smb3");
943 	bool skip_parsing = false;
944 	kuid_t uid;
945 	kgid_t gid;
946 
947 	cifs_dbg(FYI, "CIFS: parsing cifs mount option '%s'\n", param->key);
948 
949 	/*
950 	 * fs_parse can not handle string options with an empty value so
951 	 * we will need special handling of them.
952 	 */
953 	if (param->type == fs_value_is_string && param->string[0] == 0) {
954 		if (!strcmp("pass", param->key) || !strcmp("password", param->key)) {
955 			skip_parsing = true;
956 			opt = Opt_pass;
957 		} else if (!strcmp("user", param->key) || !strcmp("username", param->key)) {
958 			skip_parsing = true;
959 			opt = Opt_user;
960 		}
961 	}
962 
963 	if (!skip_parsing) {
964 		opt = fs_parse(fc, smb3_fs_parameters, param, &result);
965 		if (opt < 0)
966 			return ctx->sloppy ? 1 : opt;
967 	}
968 
969 	switch (opt) {
970 	case Opt_compress:
971 		ctx->compress = true;
972 		cifs_dbg(VFS,
973 			"SMB3 compression support is experimental\n");
974 		break;
975 	case Opt_nodfs:
976 		ctx->nodfs = 1;
977 		break;
978 	case Opt_hard:
979 		if (result.negated) {
980 			if (ctx->retry == 1)
981 				cifs_dbg(VFS, "conflicting hard vs. soft mount options\n");
982 			ctx->retry = 0;
983 		} else
984 			ctx->retry = 1;
985 		break;
986 	case Opt_soft:
987 		if (result.negated)
988 			ctx->retry = 1;
989 		else {
990 			if (ctx->retry == 1)
991 				cifs_dbg(VFS, "conflicting hard vs soft mount options\n");
992 			ctx->retry = 0;
993 		}
994 		break;
995 	case Opt_mapposix:
996 		if (result.negated)
997 			ctx->remap = false;
998 		else {
999 			ctx->remap = true;
1000 			ctx->sfu_remap = false; /* disable SFU mapping */
1001 		}
1002 		break;
1003 	case Opt_mapchars:
1004 		if (result.negated)
1005 			ctx->sfu_remap = false;
1006 		else {
1007 			ctx->sfu_remap = true;
1008 			ctx->remap = false; /* disable SFM (mapposix) mapping */
1009 		}
1010 		break;
1011 	case Opt_user_xattr:
1012 		if (result.negated)
1013 			ctx->no_xattr = 1;
1014 		else
1015 			ctx->no_xattr = 0;
1016 		break;
1017 	case Opt_forceuid:
1018 		if (result.negated)
1019 			ctx->override_uid = 0;
1020 		else
1021 			ctx->override_uid = 1;
1022 		break;
1023 	case Opt_forcegid:
1024 		if (result.negated)
1025 			ctx->override_gid = 0;
1026 		else
1027 			ctx->override_gid = 1;
1028 		break;
1029 	case Opt_perm:
1030 		if (result.negated)
1031 			ctx->noperm = 1;
1032 		else
1033 			ctx->noperm = 0;
1034 		break;
1035 	case Opt_dynperm:
1036 		if (result.negated)
1037 			ctx->dynperm = 0;
1038 		else
1039 			ctx->dynperm = 1;
1040 		break;
1041 	case Opt_sfu:
1042 		if (result.negated)
1043 			ctx->sfu_emul = 0;
1044 		else
1045 			ctx->sfu_emul = 1;
1046 		break;
1047 	case Opt_noblocksend:
1048 		ctx->noblocksnd = 1;
1049 		break;
1050 	case Opt_noautotune:
1051 		ctx->noautotune = 1;
1052 		break;
1053 	case Opt_nolease:
1054 		ctx->no_lease = 1;
1055 		break;
1056 	case Opt_nosparse:
1057 		ctx->no_sparse = 1;
1058 		break;
1059 	case Opt_nodelete:
1060 		ctx->nodelete = 1;
1061 		break;
1062 	case Opt_multichannel:
1063 		if (result.negated) {
1064 			ctx->multichannel = false;
1065 			ctx->max_channels = 1;
1066 		} else {
1067 			ctx->multichannel = true;
1068 			/* if number of channels not specified, default to 2 */
1069 			if (ctx->max_channels < 2)
1070 				ctx->max_channels = 2;
1071 		}
1072 		break;
1073 	case Opt_uid:
1074 		uid = make_kuid(current_user_ns(), result.uint_32);
1075 		if (!uid_valid(uid))
1076 			goto cifs_parse_mount_err;
1077 		ctx->linux_uid = uid;
1078 		ctx->uid_specified = true;
1079 		break;
1080 	case Opt_cruid:
1081 		uid = make_kuid(current_user_ns(), result.uint_32);
1082 		if (!uid_valid(uid))
1083 			goto cifs_parse_mount_err;
1084 		ctx->cred_uid = uid;
1085 		ctx->cruid_specified = true;
1086 		break;
1087 	case Opt_backupuid:
1088 		uid = make_kuid(current_user_ns(), result.uint_32);
1089 		if (!uid_valid(uid))
1090 			goto cifs_parse_mount_err;
1091 		ctx->backupuid = uid;
1092 		ctx->backupuid_specified = true;
1093 		break;
1094 	case Opt_backupgid:
1095 		gid = make_kgid(current_user_ns(), result.uint_32);
1096 		if (!gid_valid(gid))
1097 			goto cifs_parse_mount_err;
1098 		ctx->backupgid = gid;
1099 		ctx->backupgid_specified = true;
1100 		break;
1101 	case Opt_gid:
1102 		gid = make_kgid(current_user_ns(), result.uint_32);
1103 		if (!gid_valid(gid))
1104 			goto cifs_parse_mount_err;
1105 		ctx->linux_gid = gid;
1106 		ctx->gid_specified = true;
1107 		break;
1108 	case Opt_port:
1109 		ctx->port = result.uint_32;
1110 		break;
1111 	case Opt_file_mode:
1112 		ctx->file_mode = result.uint_32;
1113 		break;
1114 	case Opt_dirmode:
1115 		ctx->dir_mode = result.uint_32;
1116 		break;
1117 	case Opt_min_enc_offload:
1118 		ctx->min_offload = result.uint_32;
1119 		break;
1120 	case Opt_retrans:
1121 		ctx->retrans = result.uint_32;
1122 		break;
1123 	case Opt_blocksize:
1124 		/*
1125 		 * inode blocksize realistically should never need to be
1126 		 * less than 16K or greater than 16M and default is 1MB.
1127 		 * Note that small inode block sizes (e.g. 64K) can lead
1128 		 * to very poor performance of common tools like cp and scp
1129 		 */
1130 		if ((result.uint_32 < CIFS_MAX_MSGSIZE) ||
1131 		   (result.uint_32 > (4 * SMB3_DEFAULT_IOSIZE))) {
1132 			cifs_errorf(fc, "%s: Invalid blocksize\n",
1133 				__func__);
1134 			goto cifs_parse_mount_err;
1135 		}
1136 		ctx->bsize = result.uint_32;
1137 		ctx->got_bsize = true;
1138 		break;
1139 	case Opt_rasize:
1140 		/*
1141 		 * readahead size realistically should never need to be
1142 		 * less than 1M (CIFS_DEFAULT_IOSIZE) or greater than 32M
1143 		 * (perhaps an exception should be considered in the
1144 		 * for the case of a large number of channels
1145 		 * when multichannel is negotiated) since that would lead
1146 		 * to plenty of parallel I/O in flight to the server.
1147 		 * Note that smaller read ahead sizes would
1148 		 * hurt performance of common tools like cp and scp
1149 		 * which often trigger sequential i/o with read ahead
1150 		 */
1151 		if ((result.uint_32 > (8 * SMB3_DEFAULT_IOSIZE)) ||
1152 		    (result.uint_32 < CIFS_DEFAULT_IOSIZE)) {
1153 			cifs_errorf(fc, "%s: Invalid rasize %d vs. %d\n",
1154 				__func__, result.uint_32, SMB3_DEFAULT_IOSIZE);
1155 			goto cifs_parse_mount_err;
1156 		}
1157 		ctx->rasize = result.uint_32;
1158 		break;
1159 	case Opt_rsize:
1160 		ctx->rsize = result.uint_32;
1161 		ctx->got_rsize = true;
1162 		break;
1163 	case Opt_wsize:
1164 		ctx->wsize = result.uint_32;
1165 		ctx->got_wsize = true;
1166 		if (ctx->wsize % PAGE_SIZE != 0) {
1167 			ctx->wsize = round_down(ctx->wsize, PAGE_SIZE);
1168 			if (ctx->wsize == 0) {
1169 				ctx->wsize = PAGE_SIZE;
1170 				cifs_dbg(VFS, "wsize too small, reset to minimum %ld\n", PAGE_SIZE);
1171 			} else {
1172 				cifs_dbg(VFS,
1173 					 "wsize rounded down to %d to multiple of PAGE_SIZE %ld\n",
1174 					 ctx->wsize, PAGE_SIZE);
1175 			}
1176 		}
1177 		break;
1178 	case Opt_acregmax:
1179 		ctx->acregmax = HZ * result.uint_32;
1180 		if (ctx->acregmax > CIFS_MAX_ACTIMEO) {
1181 			cifs_errorf(fc, "acregmax too large\n");
1182 			goto cifs_parse_mount_err;
1183 		}
1184 		break;
1185 	case Opt_acdirmax:
1186 		ctx->acdirmax = HZ * result.uint_32;
1187 		if (ctx->acdirmax > CIFS_MAX_ACTIMEO) {
1188 			cifs_errorf(fc, "acdirmax too large\n");
1189 			goto cifs_parse_mount_err;
1190 		}
1191 		break;
1192 	case Opt_actimeo:
1193 		if (HZ * result.uint_32 > CIFS_MAX_ACTIMEO) {
1194 			cifs_errorf(fc, "timeout too large\n");
1195 			goto cifs_parse_mount_err;
1196 		}
1197 		if ((ctx->acdirmax != CIFS_DEF_ACTIMEO) ||
1198 		    (ctx->acregmax != CIFS_DEF_ACTIMEO)) {
1199 			cifs_errorf(fc, "actimeo ignored since acregmax or acdirmax specified\n");
1200 			break;
1201 		}
1202 		ctx->acdirmax = ctx->acregmax = HZ * result.uint_32;
1203 		break;
1204 	case Opt_closetimeo:
1205 		ctx->closetimeo = HZ * result.uint_32;
1206 		if (ctx->closetimeo > SMB3_MAX_DCLOSETIMEO) {
1207 			cifs_errorf(fc, "closetimeo too large\n");
1208 			goto cifs_parse_mount_err;
1209 		}
1210 		break;
1211 	case Opt_echo_interval:
1212 		ctx->echo_interval = result.uint_32;
1213 		break;
1214 	case Opt_snapshot:
1215 		ctx->snapshot_time = result.uint_64;
1216 		break;
1217 	case Opt_max_credits:
1218 		if (result.uint_32 < 20 || result.uint_32 > 60000) {
1219 			cifs_errorf(fc, "%s: Invalid max_credits value\n",
1220 				 __func__);
1221 			goto cifs_parse_mount_err;
1222 		}
1223 		ctx->max_credits = result.uint_32;
1224 		break;
1225 	case Opt_max_channels:
1226 		if (result.uint_32 < 1 || result.uint_32 > CIFS_MAX_CHANNELS) {
1227 			cifs_errorf(fc, "%s: Invalid max_channels value, needs to be 1-%d\n",
1228 				 __func__, CIFS_MAX_CHANNELS);
1229 			goto cifs_parse_mount_err;
1230 		}
1231 		ctx->max_channels = result.uint_32;
1232 		/* If more than one channel requested ... they want multichan */
1233 		if (result.uint_32 > 1)
1234 			ctx->multichannel = true;
1235 		break;
1236 	case Opt_max_cached_dirs:
1237 		if (result.uint_32 < 1) {
1238 			cifs_errorf(fc, "%s: Invalid max_cached_dirs, needs to be 1 or more\n",
1239 				    __func__);
1240 			goto cifs_parse_mount_err;
1241 		}
1242 		ctx->max_cached_dirs = result.uint_32;
1243 		break;
1244 	case Opt_handletimeout:
1245 		ctx->handle_timeout = result.uint_32;
1246 		if (ctx->handle_timeout > SMB3_MAX_HANDLE_TIMEOUT) {
1247 			cifs_errorf(fc, "Invalid handle cache timeout, longer than 16 minutes\n");
1248 			goto cifs_parse_mount_err;
1249 		}
1250 		break;
1251 	case Opt_source:
1252 		kfree(ctx->UNC);
1253 		ctx->UNC = NULL;
1254 		switch (smb3_parse_devname(param->string, ctx)) {
1255 		case 0:
1256 			break;
1257 		case -ENOMEM:
1258 			cifs_errorf(fc, "Unable to allocate memory for devname\n");
1259 			goto cifs_parse_mount_err;
1260 		case -EINVAL:
1261 			cifs_errorf(fc, "Malformed UNC in devname\n");
1262 			goto cifs_parse_mount_err;
1263 		default:
1264 			cifs_errorf(fc, "Unknown error parsing devname\n");
1265 			goto cifs_parse_mount_err;
1266 		}
1267 		ctx->source = smb3_fs_context_fullpath(ctx, '/');
1268 		if (IS_ERR(ctx->source)) {
1269 			ctx->source = NULL;
1270 			cifs_errorf(fc, "OOM when copying UNC string\n");
1271 			goto cifs_parse_mount_err;
1272 		}
1273 		fc->source = kstrdup(ctx->source, GFP_KERNEL);
1274 		if (fc->source == NULL) {
1275 			cifs_errorf(fc, "OOM when copying UNC string\n");
1276 			goto cifs_parse_mount_err;
1277 		}
1278 		break;
1279 	case Opt_user:
1280 		kfree(ctx->username);
1281 		ctx->username = NULL;
1282 		if (ctx->nullauth)
1283 			break;
1284 		if (strlen(param->string) == 0) {
1285 			/* null user, ie. anonymous authentication */
1286 			ctx->nullauth = 1;
1287 			break;
1288 		}
1289 
1290 		if (strnlen(param->string, CIFS_MAX_USERNAME_LEN) >
1291 		    CIFS_MAX_USERNAME_LEN) {
1292 			pr_warn("username too long\n");
1293 			goto cifs_parse_mount_err;
1294 		}
1295 		ctx->username = kstrdup(param->string, GFP_KERNEL);
1296 		if (ctx->username == NULL) {
1297 			cifs_errorf(fc, "OOM when copying username string\n");
1298 			goto cifs_parse_mount_err;
1299 		}
1300 		break;
1301 	case Opt_pass:
1302 		kfree_sensitive(ctx->password);
1303 		ctx->password = NULL;
1304 		if (strlen(param->string) == 0)
1305 			break;
1306 
1307 		ctx->password = kstrdup(param->string, GFP_KERNEL);
1308 		if (ctx->password == NULL) {
1309 			cifs_errorf(fc, "OOM when copying password string\n");
1310 			goto cifs_parse_mount_err;
1311 		}
1312 		break;
1313 	case Opt_pass2:
1314 		kfree_sensitive(ctx->password2);
1315 		ctx->password2 = NULL;
1316 		if (strlen(param->string) == 0)
1317 			break;
1318 
1319 		ctx->password2 = kstrdup(param->string, GFP_KERNEL);
1320 		if (ctx->password2 == NULL) {
1321 			cifs_errorf(fc, "OOM when copying password2 string\n");
1322 			goto cifs_parse_mount_err;
1323 		}
1324 		break;
1325 	case Opt_ip:
1326 		if (strlen(param->string) == 0) {
1327 			ctx->got_ip = false;
1328 			break;
1329 		}
1330 		if (!cifs_convert_address((struct sockaddr *)&ctx->dstaddr,
1331 					  param->string,
1332 					  strlen(param->string))) {
1333 			pr_err("bad ip= option (%s)\n", param->string);
1334 			goto cifs_parse_mount_err;
1335 		}
1336 		ctx->got_ip = true;
1337 		break;
1338 	case Opt_domain:
1339 		if (strnlen(param->string, CIFS_MAX_DOMAINNAME_LEN)
1340 				== CIFS_MAX_DOMAINNAME_LEN) {
1341 			pr_warn("domain name too long\n");
1342 			goto cifs_parse_mount_err;
1343 		}
1344 
1345 		kfree(ctx->domainname);
1346 		ctx->domainname = kstrdup(param->string, GFP_KERNEL);
1347 		if (ctx->domainname == NULL) {
1348 			cifs_errorf(fc, "OOM when copying domainname string\n");
1349 			goto cifs_parse_mount_err;
1350 		}
1351 		cifs_dbg(FYI, "Domain name set\n");
1352 		break;
1353 	case Opt_srcaddr:
1354 		if (!cifs_convert_address(
1355 				(struct sockaddr *)&ctx->srcaddr,
1356 				param->string, strlen(param->string))) {
1357 			pr_warn("Could not parse srcaddr: %s\n",
1358 				param->string);
1359 			goto cifs_parse_mount_err;
1360 		}
1361 		break;
1362 	case Opt_iocharset:
1363 		if (strnlen(param->string, 1024) >= 65) {
1364 			pr_warn("iocharset name too long\n");
1365 			goto cifs_parse_mount_err;
1366 		}
1367 
1368 		if (strncasecmp(param->string, "default", 7) != 0) {
1369 			kfree(ctx->iocharset);
1370 			ctx->iocharset = kstrdup(param->string, GFP_KERNEL);
1371 			if (ctx->iocharset == NULL) {
1372 				cifs_errorf(fc, "OOM when copying iocharset string\n");
1373 				goto cifs_parse_mount_err;
1374 			}
1375 		}
1376 		/* if iocharset not set then load_nls_default
1377 		 * is used by caller
1378 		 */
1379 		cifs_dbg(FYI, "iocharset set to %s\n", ctx->iocharset);
1380 		break;
1381 	case Opt_netbiosname:
1382 		memset(ctx->source_rfc1001_name, 0x20,
1383 			RFC1001_NAME_LEN);
1384 		/*
1385 		 * FIXME: are there cases in which a comma can
1386 		 * be valid in workstation netbios name (and
1387 		 * need special handling)?
1388 		 */
1389 		for (i = 0; i < RFC1001_NAME_LEN; i++) {
1390 			/* don't ucase netbiosname for user */
1391 			if (param->string[i] == 0)
1392 				break;
1393 			ctx->source_rfc1001_name[i] = param->string[i];
1394 		}
1395 		/* The string has 16th byte zero still from
1396 		 * set at top of the function
1397 		 */
1398 		if (i == RFC1001_NAME_LEN && param->string[i] != 0)
1399 			pr_warn("netbiosname longer than 15 truncated\n");
1400 		break;
1401 	case Opt_servern:
1402 		/* last byte, type, is 0x20 for servr type */
1403 		memset(ctx->target_rfc1001_name, 0x20,
1404 			RFC1001_NAME_LEN_WITH_NULL);
1405 		/*
1406 		 * BB are there cases in which a comma can be valid in this
1407 		 * workstation netbios name (and need special handling)?
1408 		 */
1409 
1410 		/* user or mount helper must uppercase the netbios name */
1411 		for (i = 0; i < 15; i++) {
1412 			if (param->string[i] == 0)
1413 				break;
1414 			ctx->target_rfc1001_name[i] = param->string[i];
1415 		}
1416 
1417 		/* The string has 16th byte zero still from set at top of function */
1418 		if (i == RFC1001_NAME_LEN && param->string[i] != 0)
1419 			pr_warn("server netbiosname longer than 15 truncated\n");
1420 		break;
1421 	case Opt_ver:
1422 		/* version of mount userspace tools, not dialect */
1423 		/* If interface changes in mount.cifs bump to new ver */
1424 		if (strncasecmp(param->string, "1", 1) == 0) {
1425 			if (strlen(param->string) > 1) {
1426 				pr_warn("Bad mount helper ver=%s. Did you want SMB1 (CIFS) dialect and mean to type vers=1.0 instead?\n",
1427 					param->string);
1428 				goto cifs_parse_mount_err;
1429 			}
1430 			/* This is the default */
1431 			break;
1432 		}
1433 		/* For all other value, error */
1434 		pr_warn("Invalid mount helper version specified\n");
1435 		goto cifs_parse_mount_err;
1436 	case Opt_vers:
1437 		/* protocol version (dialect) */
1438 		if (cifs_parse_smb_version(fc, param->string, ctx, is_smb3) != 0)
1439 			goto cifs_parse_mount_err;
1440 		ctx->got_version = true;
1441 		break;
1442 	case Opt_sec:
1443 		if (cifs_parse_security_flavors(fc, param->string, ctx) != 0)
1444 			goto cifs_parse_mount_err;
1445 		break;
1446 	case Opt_cache:
1447 		if (cifs_parse_cache_flavor(fc, param->string, ctx) != 0)
1448 			goto cifs_parse_mount_err;
1449 		break;
1450 	case Opt_witness:
1451 #ifndef CONFIG_CIFS_SWN_UPCALL
1452 		cifs_errorf(fc, "Witness support needs CONFIG_CIFS_SWN_UPCALL config option\n");
1453 			goto cifs_parse_mount_err;
1454 #endif
1455 		ctx->witness = true;
1456 		pr_warn_once("Witness protocol support is experimental\n");
1457 		break;
1458 	case Opt_rootfs:
1459 #ifndef CONFIG_CIFS_ROOT
1460 		cifs_dbg(VFS, "rootfs support requires CONFIG_CIFS_ROOT config option\n");
1461 		goto cifs_parse_mount_err;
1462 #endif
1463 		ctx->rootfs = true;
1464 		break;
1465 	case Opt_posixpaths:
1466 		if (result.negated)
1467 			ctx->posix_paths = 0;
1468 		else
1469 			ctx->posix_paths = 1;
1470 		break;
1471 	case Opt_unix:
1472 		if (result.negated) {
1473 			if (ctx->linux_ext == 1)
1474 				pr_warn_once("conflicting posix mount options specified\n");
1475 			ctx->linux_ext = 0;
1476 			ctx->no_linux_ext = 1;
1477 		} else {
1478 			if (ctx->no_linux_ext == 1)
1479 				pr_warn_once("conflicting posix mount options specified\n");
1480 			ctx->linux_ext = 1;
1481 			ctx->no_linux_ext = 0;
1482 		}
1483 		break;
1484 	case Opt_nocase:
1485 		ctx->nocase = 1;
1486 		break;
1487 	case Opt_brl:
1488 		if (result.negated) {
1489 			/*
1490 			 * turn off mandatory locking in mode
1491 			 * if remote locking is turned off since the
1492 			 * local vfs will do advisory
1493 			 */
1494 			if (ctx->file_mode ==
1495 				(S_IALLUGO & ~(S_ISUID | S_IXGRP)))
1496 				ctx->file_mode = S_IALLUGO;
1497 			ctx->nobrl =  1;
1498 		} else
1499 			ctx->nobrl =  0;
1500 		break;
1501 	case Opt_handlecache:
1502 		if (result.negated)
1503 			ctx->nohandlecache = 1;
1504 		else
1505 			ctx->nohandlecache = 0;
1506 		break;
1507 	case Opt_forcemandatorylock:
1508 		ctx->mand_lock = 1;
1509 		break;
1510 	case Opt_setuids:
1511 		ctx->setuids = result.negated;
1512 		break;
1513 	case Opt_intr:
1514 		ctx->intr = !result.negated;
1515 		break;
1516 	case Opt_setuidfromacl:
1517 		ctx->setuidfromacl = 1;
1518 		break;
1519 	case Opt_strictsync:
1520 		ctx->nostrictsync = result.negated;
1521 		break;
1522 	case Opt_serverino:
1523 		ctx->server_ino = !result.negated;
1524 		break;
1525 	case Opt_rwpidforward:
1526 		ctx->rwpidforward = 1;
1527 		break;
1528 	case Opt_modesid:
1529 		ctx->mode_ace = 1;
1530 		break;
1531 	case Opt_cifsacl:
1532 		ctx->cifs_acl = !result.negated;
1533 		break;
1534 	case Opt_acl:
1535 		ctx->no_psx_acl = result.negated;
1536 		break;
1537 	case Opt_locallease:
1538 		ctx->local_lease = 1;
1539 		break;
1540 	case Opt_sign:
1541 		ctx->sign = true;
1542 		break;
1543 	case Opt_ignore_signature:
1544 		ctx->sign = true;
1545 		ctx->ignore_signature = true;
1546 		break;
1547 	case Opt_seal:
1548 		/* we do not do the following in secFlags because seal
1549 		 * is a per tree connection (mount) not a per socket
1550 		 * or per-smb connection option in the protocol
1551 		 * vol->secFlg |= CIFSSEC_MUST_SEAL;
1552 		 */
1553 		ctx->seal = 1;
1554 		break;
1555 	case Opt_noac:
1556 		pr_warn("Mount option noac not supported. Instead set /proc/fs/cifs/LookupCacheEnabled to 0\n");
1557 		break;
1558 	case Opt_fsc:
1559 #ifndef CONFIG_CIFS_FSCACHE
1560 		cifs_errorf(fc, "FS-Cache support needs CONFIG_CIFS_FSCACHE kernel config option set\n");
1561 		goto cifs_parse_mount_err;
1562 #endif
1563 		ctx->fsc = true;
1564 		break;
1565 	case Opt_mfsymlinks:
1566 		ctx->mfsymlinks = true;
1567 		break;
1568 	case Opt_multiuser:
1569 		ctx->multiuser = true;
1570 		break;
1571 	case Opt_sloppy:
1572 		ctx->sloppy = true;
1573 		break;
1574 	case Opt_nosharesock:
1575 		ctx->nosharesock = true;
1576 		break;
1577 	case Opt_persistent:
1578 		if (result.negated) {
1579 			ctx->nopersistent = true;
1580 			if (ctx->persistent) {
1581 				cifs_errorf(fc, "persistenthandles mount options conflict\n");
1582 				goto cifs_parse_mount_err;
1583 			}
1584 		} else {
1585 			ctx->persistent = true;
1586 			if ((ctx->nopersistent) || (ctx->resilient)) {
1587 				cifs_errorf(fc, "persistenthandles mount options conflict\n");
1588 				goto cifs_parse_mount_err;
1589 			}
1590 		}
1591 		break;
1592 	case Opt_resilient:
1593 		if (result.negated) {
1594 			ctx->resilient = false; /* already the default */
1595 		} else {
1596 			ctx->resilient = true;
1597 			if (ctx->persistent) {
1598 				cifs_errorf(fc, "persistenthandles mount options conflict\n");
1599 				goto cifs_parse_mount_err;
1600 			}
1601 		}
1602 		break;
1603 	case Opt_tcp_nodelay:
1604 		/* tcp nodelay should not usually be needed since we CORK/UNCORK the socket */
1605 		if (result.negated)
1606 			ctx->sockopt_tcp_nodelay = false;
1607 		else
1608 			ctx->sockopt_tcp_nodelay = true;
1609 		break;
1610 	case Opt_domainauto:
1611 		ctx->domainauto = true;
1612 		break;
1613 	case Opt_rdma:
1614 		ctx->rdma = true;
1615 		break;
1616 	case Opt_reparse:
1617 		if (parse_reparse_flavor(fc, param->string, ctx))
1618 			goto cifs_parse_mount_err;
1619 		break;
1620 	}
1621 	/* case Opt_ignore: - is ignored as expected ... */
1622 
1623 	return 0;
1624 
1625  cifs_parse_mount_err:
1626 	kfree_sensitive(ctx->password);
1627 	ctx->password = NULL;
1628 	kfree_sensitive(ctx->password2);
1629 	ctx->password2 = NULL;
1630 	return -EINVAL;
1631 }
1632 
1633 int smb3_init_fs_context(struct fs_context *fc)
1634 {
1635 	struct smb3_fs_context *ctx;
1636 	char *nodename = utsname()->nodename;
1637 	int i;
1638 
1639 	ctx = kzalloc(sizeof(struct smb3_fs_context), GFP_KERNEL);
1640 	if (unlikely(!ctx))
1641 		return -ENOMEM;
1642 
1643 	strscpy(ctx->workstation_name, nodename, sizeof(ctx->workstation_name));
1644 
1645 	/*
1646 	 * does not have to be perfect mapping since field is
1647 	 * informational, only used for servers that do not support
1648 	 * port 445 and it can be overridden at mount time
1649 	 */
1650 	memset(ctx->source_rfc1001_name, 0x20, RFC1001_NAME_LEN);
1651 	for (i = 0; i < strnlen(nodename, RFC1001_NAME_LEN); i++)
1652 		ctx->source_rfc1001_name[i] = toupper(nodename[i]);
1653 
1654 	ctx->source_rfc1001_name[RFC1001_NAME_LEN] = 0;
1655 	/*
1656 	 * null target name indicates to use *SMBSERVR default called name
1657 	 *  if we end up sending RFC1001 session initialize
1658 	 */
1659 	ctx->target_rfc1001_name[0] = 0;
1660 	ctx->cred_uid = current_uid();
1661 	ctx->linux_uid = current_uid();
1662 	ctx->linux_gid = current_gid();
1663 	/* By default 4MB read ahead size, 1MB block size */
1664 	ctx->bsize = CIFS_DEFAULT_IOSIZE; /* can improve cp performance significantly */
1665 	ctx->rasize = 0; /* 0 = use default (ie negotiated rsize) for read ahead pages */
1666 
1667 	/*
1668 	 * default to SFM style remapping of seven reserved characters
1669 	 * unless user overrides it or we negotiate CIFS POSIX where
1670 	 * it is unnecessary.  Can not simultaneously use more than one mapping
1671 	 * since then readdir could list files that open could not open
1672 	 */
1673 	ctx->remap = true;
1674 
1675 	/* default to only allowing write access to owner of the mount */
1676 	ctx->dir_mode = ctx->file_mode = S_IRUGO | S_IXUGO | S_IWUSR;
1677 
1678 	/* ctx->retry default is 0 (i.e. "soft" limited retry not hard retry) */
1679 	/* default is always to request posix paths. */
1680 	ctx->posix_paths = 1;
1681 	/* default to using server inode numbers where available */
1682 	ctx->server_ino = 1;
1683 
1684 	/* default is to use strict cifs caching semantics */
1685 	ctx->strict_io = true;
1686 
1687 	ctx->acregmax = CIFS_DEF_ACTIMEO;
1688 	ctx->acdirmax = CIFS_DEF_ACTIMEO;
1689 	ctx->closetimeo = SMB3_DEF_DCLOSETIMEO;
1690 	ctx->max_cached_dirs = MAX_CACHED_FIDS;
1691 	/* Most clients set timeout to 0, allows server to use its default */
1692 	ctx->handle_timeout = 0; /* See MS-SMB2 spec section 2.2.14.2.12 */
1693 
1694 	/* offer SMB2.1 and later (SMB3 etc). Secure and widely accepted */
1695 	ctx->ops = &smb30_operations;
1696 	ctx->vals = &smbdefault_values;
1697 
1698 	ctx->echo_interval = SMB_ECHO_INTERVAL_DEFAULT;
1699 
1700 	/* default to no multichannel (single server connection) */
1701 	ctx->multichannel = false;
1702 	ctx->max_channels = 1;
1703 
1704 	ctx->backupuid_specified = false; /* no backup intent for a user */
1705 	ctx->backupgid_specified = false; /* no backup intent for a group */
1706 
1707 	ctx->retrans = 1;
1708 	ctx->reparse_type = CIFS_REPARSE_TYPE_DEFAULT;
1709 
1710 /*
1711  *	short int override_uid = -1;
1712  *	short int override_gid = -1;
1713  *	char *nodename = strdup(utsname()->nodename);
1714  *	struct sockaddr *dstaddr = (struct sockaddr *)&vol->dstaddr;
1715  */
1716 
1717 	fc->fs_private = ctx;
1718 	fc->ops = &smb3_fs_context_ops;
1719 	return 0;
1720 }
1721 
1722 void
1723 smb3_cleanup_fs_context_contents(struct smb3_fs_context *ctx)
1724 {
1725 	if (ctx == NULL)
1726 		return;
1727 
1728 	/*
1729 	 * Make sure this stays in sync with smb3_fs_context_dup()
1730 	 */
1731 	kfree(ctx->username);
1732 	ctx->username = NULL;
1733 	kfree_sensitive(ctx->password);
1734 	ctx->password = NULL;
1735 	kfree_sensitive(ctx->password2);
1736 	ctx->password2 = NULL;
1737 	kfree(ctx->server_hostname);
1738 	ctx->server_hostname = NULL;
1739 	kfree(ctx->UNC);
1740 	ctx->UNC = NULL;
1741 	kfree(ctx->source);
1742 	ctx->source = NULL;
1743 	kfree(ctx->domainname);
1744 	ctx->domainname = NULL;
1745 	kfree(ctx->nodename);
1746 	ctx->nodename = NULL;
1747 	kfree(ctx->iocharset);
1748 	ctx->iocharset = NULL;
1749 	kfree(ctx->prepath);
1750 	ctx->prepath = NULL;
1751 	kfree(ctx->leaf_fullpath);
1752 	ctx->leaf_fullpath = NULL;
1753 }
1754 
1755 void
1756 smb3_cleanup_fs_context(struct smb3_fs_context *ctx)
1757 {
1758 	if (!ctx)
1759 		return;
1760 	smb3_cleanup_fs_context_contents(ctx);
1761 	kfree(ctx);
1762 }
1763 
1764 void smb3_update_mnt_flags(struct cifs_sb_info *cifs_sb)
1765 {
1766 	struct smb3_fs_context *ctx = cifs_sb->ctx;
1767 
1768 	if (ctx->nodfs)
1769 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_DFS;
1770 	else
1771 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NO_DFS;
1772 
1773 	if (ctx->noperm)
1774 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_PERM;
1775 	else
1776 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NO_PERM;
1777 
1778 	if (ctx->setuids)
1779 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_SET_UID;
1780 	else
1781 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SET_UID;
1782 
1783 	if (ctx->setuidfromacl)
1784 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_UID_FROM_ACL;
1785 	else
1786 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_UID_FROM_ACL;
1787 
1788 	if (ctx->server_ino)
1789 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_SERVER_INUM;
1790 	else
1791 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
1792 
1793 	if (ctx->remap)
1794 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MAP_SFM_CHR;
1795 	else
1796 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_MAP_SFM_CHR;
1797 
1798 	if (ctx->sfu_remap)
1799 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MAP_SPECIAL_CHR;
1800 	else
1801 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_MAP_SPECIAL_CHR;
1802 
1803 	if (ctx->no_xattr)
1804 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_XATTR;
1805 	else
1806 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NO_XATTR;
1807 
1808 	if (ctx->sfu_emul)
1809 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_UNX_EMUL;
1810 	else
1811 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_UNX_EMUL;
1812 
1813 	if (ctx->nobrl)
1814 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_BRL;
1815 	else
1816 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NO_BRL;
1817 
1818 	if (ctx->nohandlecache)
1819 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NO_HANDLE_CACHE;
1820 	else
1821 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NO_HANDLE_CACHE;
1822 
1823 	if (ctx->nostrictsync)
1824 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NOSSYNC;
1825 	else
1826 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NOSSYNC;
1827 
1828 	if (ctx->mand_lock)
1829 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_NOPOSIXBRL;
1830 	else
1831 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_NOPOSIXBRL;
1832 
1833 	if (ctx->rwpidforward)
1834 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_RWPIDFORWARD;
1835 	else
1836 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_RWPIDFORWARD;
1837 
1838 	if (ctx->mode_ace)
1839 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MODE_FROM_SID;
1840 	else
1841 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_MODE_FROM_SID;
1842 
1843 	if (ctx->cifs_acl)
1844 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_CIFS_ACL;
1845 	else
1846 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_CIFS_ACL;
1847 
1848 	if (ctx->backupuid_specified)
1849 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_CIFS_BACKUPUID;
1850 	else
1851 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_CIFS_BACKUPUID;
1852 
1853 	if (ctx->backupgid_specified)
1854 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_CIFS_BACKUPGID;
1855 	else
1856 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_CIFS_BACKUPGID;
1857 
1858 	if (ctx->override_uid)
1859 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_UID;
1860 	else
1861 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_OVERR_UID;
1862 
1863 	if (ctx->override_gid)
1864 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_OVERR_GID;
1865 	else
1866 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_OVERR_GID;
1867 
1868 	if (ctx->dynperm)
1869 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DYNPERM;
1870 	else
1871 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_DYNPERM;
1872 
1873 	if (ctx->fsc)
1874 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_FSCACHE;
1875 	else
1876 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_FSCACHE;
1877 
1878 	if (ctx->multiuser)
1879 		cifs_sb->mnt_cifs_flags |= (CIFS_MOUNT_MULTIUSER |
1880 					    CIFS_MOUNT_NO_PERM);
1881 	else
1882 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_MULTIUSER;
1883 
1884 
1885 	if (ctx->strict_io)
1886 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_STRICT_IO;
1887 	else
1888 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_STRICT_IO;
1889 
1890 	if (ctx->direct_io)
1891 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_DIRECT_IO;
1892 	else
1893 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_DIRECT_IO;
1894 
1895 	if (ctx->mfsymlinks)
1896 		cifs_sb->mnt_cifs_flags |= CIFS_MOUNT_MF_SYMLINKS;
1897 	else
1898 		cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_MF_SYMLINKS;
1899 	if (ctx->mfsymlinks) {
1900 		if (ctx->sfu_emul) {
1901 			/*
1902 			 * Our SFU ("Services for Unix" emulation does not allow
1903 			 * creating symlinks but does allow reading existing SFU
1904 			 * symlinks (it does allow both creating and reading SFU
1905 			 * style mknod and FIFOs though). When "mfsymlinks" and
1906 			 * "sfu" are both enabled at the same time, it allows
1907 			 * reading both types of symlinks, but will only create
1908 			 * them with mfsymlinks format. This allows better
1909 			 * Apple compatibility (probably better for Samba too)
1910 			 * while still recognizing old Windows style symlinks.
1911 			 */
1912 			cifs_dbg(VFS, "mount options mfsymlinks and sfu both enabled\n");
1913 		}
1914 	}
1915 	cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SHUTDOWN;
1916 
1917 	return;
1918 }
1919