1 // SPDX-License-Identifier: LGPL-2.1
2 /*
3  *
4  *   Copyright (C) International Business Machines  Corp., 2002,2008
5  *   Author(s): Steve French ([email protected])
6  *
7  */
8 #include <linux/fs.h>
9 #include <linux/stat.h>
10 #include <linux/slab.h>
11 #include <linux/namei.h>
12 #include "cifsfs.h"
13 #include "cifspdu.h"
14 #include "cifsglob.h"
15 #include "cifsproto.h"
16 #include "cifs_debug.h"
17 #include "cifs_fs_sb.h"
18 #include "cifs_unicode.h"
19 #include "smb2proto.h"
20 #include "cifs_ioctl.h"
21 #include "fs_context.h"
22 
23 /*
24  * M-F Symlink Functions - Begin
25  */
26 
27 #define CIFS_MF_SYMLINK_LEN_OFFSET (4+1)
28 #define CIFS_MF_SYMLINK_MD5_OFFSET (CIFS_MF_SYMLINK_LEN_OFFSET+(4+1))
29 #define CIFS_MF_SYMLINK_LINK_OFFSET (CIFS_MF_SYMLINK_MD5_OFFSET+(32+1))
30 #define CIFS_MF_SYMLINK_LINK_MAXLEN (1024)
31 #define CIFS_MF_SYMLINK_FILE_SIZE \
32 	(CIFS_MF_SYMLINK_LINK_OFFSET + CIFS_MF_SYMLINK_LINK_MAXLEN)
33 
34 #define CIFS_MF_SYMLINK_LEN_FORMAT "XSym\n%04u\n"
35 #define CIFS_MF_SYMLINK_MD5_FORMAT "%16phN\n"
36 #define CIFS_MF_SYMLINK_MD5_ARGS(md5_hash) md5_hash
37 
38 static int
symlink_hash(unsigned int link_len,const char * link_str,u8 * md5_hash)39 symlink_hash(unsigned int link_len, const char *link_str, u8 *md5_hash)
40 {
41 	int rc;
42 	struct shash_desc *md5 = NULL;
43 
44 	rc = cifs_alloc_hash("md5", &md5);
45 	if (rc)
46 		return rc;
47 
48 	rc = crypto_shash_digest(md5, link_str, link_len, md5_hash);
49 	if (rc)
50 		cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
51 	cifs_free_hash(&md5);
52 	return rc;
53 }
54 
55 static int
parse_mf_symlink(const u8 * buf,unsigned int buf_len,unsigned int * _link_len,char ** _link_str)56 parse_mf_symlink(const u8 *buf, unsigned int buf_len, unsigned int *_link_len,
57 		 char **_link_str)
58 {
59 	int rc;
60 	unsigned int link_len;
61 	const char *md5_str1;
62 	const char *link_str;
63 	u8 md5_hash[16];
64 	char md5_str2[34];
65 
66 	if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
67 		return -EINVAL;
68 
69 	md5_str1 = (const char *)&buf[CIFS_MF_SYMLINK_MD5_OFFSET];
70 	link_str = (const char *)&buf[CIFS_MF_SYMLINK_LINK_OFFSET];
71 
72 	rc = sscanf(buf, CIFS_MF_SYMLINK_LEN_FORMAT, &link_len);
73 	if (rc != 1)
74 		return -EINVAL;
75 
76 	if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
77 		return -EINVAL;
78 
79 	rc = symlink_hash(link_len, link_str, md5_hash);
80 	if (rc) {
81 		cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);
82 		return rc;
83 	}
84 
85 	scnprintf(md5_str2, sizeof(md5_str2),
86 		  CIFS_MF_SYMLINK_MD5_FORMAT,
87 		  CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
88 
89 	if (strncmp(md5_str1, md5_str2, 17) != 0)
90 		return -EINVAL;
91 
92 	if (_link_str) {
93 		*_link_str = kstrndup(link_str, link_len, GFP_KERNEL);
94 		if (!*_link_str)
95 			return -ENOMEM;
96 	}
97 
98 	*_link_len = link_len;
99 	return 0;
100 }
101 
102 static int
format_mf_symlink(u8 * buf,unsigned int buf_len,const char * link_str)103 format_mf_symlink(u8 *buf, unsigned int buf_len, const char *link_str)
104 {
105 	int rc;
106 	unsigned int link_len;
107 	unsigned int ofs;
108 	u8 md5_hash[16];
109 
110 	if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
111 		return -EINVAL;
112 
113 	link_len = strlen(link_str);
114 
115 	if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
116 		return -ENAMETOOLONG;
117 
118 	rc = symlink_hash(link_len, link_str, md5_hash);
119 	if (rc) {
120 		cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);
121 		return rc;
122 	}
123 
124 	scnprintf(buf, buf_len,
125 		  CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT,
126 		  link_len,
127 		  CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
128 
129 	ofs = CIFS_MF_SYMLINK_LINK_OFFSET;
130 	memcpy(buf + ofs, link_str, link_len);
131 
132 	ofs += link_len;
133 	if (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
134 		buf[ofs] = '\n';
135 		ofs++;
136 	}
137 
138 	while (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
139 		buf[ofs] = ' ';
140 		ofs++;
141 	}
142 
143 	return 0;
144 }
145 
146 bool
couldbe_mf_symlink(const struct cifs_fattr * fattr)147 couldbe_mf_symlink(const struct cifs_fattr *fattr)
148 {
149 	if (!S_ISREG(fattr->cf_mode))
150 		/* it's not a symlink */
151 		return false;
152 
153 	if (fattr->cf_eof != CIFS_MF_SYMLINK_FILE_SIZE)
154 		/* it's not a symlink */
155 		return false;
156 
157 	return true;
158 }
159 
160 static int
create_mf_symlink(const unsigned int xid,struct cifs_tcon * tcon,struct cifs_sb_info * cifs_sb,const char * fromName,const char * toName)161 create_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon,
162 		  struct cifs_sb_info *cifs_sb, const char *fromName,
163 		  const char *toName)
164 {
165 	int rc;
166 	u8 *buf;
167 	unsigned int bytes_written = 0;
168 
169 	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
170 	if (!buf)
171 		return -ENOMEM;
172 
173 	rc = format_mf_symlink(buf, CIFS_MF_SYMLINK_FILE_SIZE, toName);
174 	if (rc)
175 		goto out;
176 
177 	if (tcon->ses->server->ops->create_mf_symlink)
178 		rc = tcon->ses->server->ops->create_mf_symlink(xid, tcon,
179 					cifs_sb, fromName, buf, &bytes_written);
180 	else
181 		rc = -EOPNOTSUPP;
182 
183 	if (rc)
184 		goto out;
185 
186 	if (bytes_written != CIFS_MF_SYMLINK_FILE_SIZE)
187 		rc = -EIO;
188 out:
189 	kfree(buf);
190 	return rc;
191 }
192 
193 int
check_mf_symlink(unsigned int xid,struct cifs_tcon * tcon,struct cifs_sb_info * cifs_sb,struct cifs_fattr * fattr,const unsigned char * path)194 check_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
195 		 struct cifs_sb_info *cifs_sb, struct cifs_fattr *fattr,
196 		 const unsigned char *path)
197 {
198 	int rc;
199 	u8 *buf = NULL;
200 	unsigned int link_len = 0;
201 	unsigned int bytes_read = 0;
202 	char *symlink = NULL;
203 
204 	if (!couldbe_mf_symlink(fattr))
205 		/* it's not a symlink */
206 		return 0;
207 
208 	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
209 	if (!buf)
210 		return -ENOMEM;
211 
212 	if (tcon->ses->server->ops->query_mf_symlink)
213 		rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon,
214 					      cifs_sb, path, buf, &bytes_read);
215 	else
216 		rc = -ENOSYS;
217 
218 	if (rc)
219 		goto out;
220 
221 	if (bytes_read == 0) /* not a symlink */
222 		goto out;
223 
224 	rc = parse_mf_symlink(buf, bytes_read, &link_len, &symlink);
225 	if (rc == -EINVAL) {
226 		/* it's not a symlink */
227 		rc = 0;
228 		goto out;
229 	}
230 
231 	if (rc != 0)
232 		goto out;
233 
234 	/* it is a symlink */
235 	fattr->cf_eof = link_len;
236 	fattr->cf_mode &= ~S_IFMT;
237 	fattr->cf_mode |= S_IFLNK | S_IRWXU | S_IRWXG | S_IRWXO;
238 	fattr->cf_dtype = DT_LNK;
239 	fattr->cf_symlink_target = symlink;
240 out:
241 	kfree(buf);
242 	return rc;
243 }
244 
245 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
246 /*
247  * SMB 1.0 Protocol specific functions
248  */
249 
250 int
cifs_query_mf_symlink(unsigned int xid,struct cifs_tcon * tcon,struct cifs_sb_info * cifs_sb,const unsigned char * path,char * pbuf,unsigned int * pbytes_read)251 cifs_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
252 		      struct cifs_sb_info *cifs_sb, const unsigned char *path,
253 		      char *pbuf, unsigned int *pbytes_read)
254 {
255 	int rc;
256 	int oplock = 0;
257 	struct cifs_fid fid;
258 	struct cifs_open_parms oparms;
259 	struct cifs_io_parms io_parms = {0};
260 	int buf_type = CIFS_NO_BUFFER;
261 	FILE_ALL_INFO file_info;
262 
263 	oparms = (struct cifs_open_parms) {
264 		.tcon = tcon,
265 		.cifs_sb = cifs_sb,
266 		.desired_access = GENERIC_READ,
267 		.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR),
268 		.disposition = FILE_OPEN,
269 		.path = path,
270 		.fid = &fid,
271 	};
272 
273 	rc = CIFS_open(xid, &oparms, &oplock, &file_info);
274 	if (rc)
275 		return rc;
276 
277 	if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
278 		rc = -ENOENT;
279 		/* it's not a symlink */
280 		goto out;
281 	}
282 
283 	io_parms.netfid = fid.netfid;
284 	io_parms.pid = current->tgid;
285 	io_parms.tcon = tcon;
286 	io_parms.offset = 0;
287 	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
288 
289 	rc = CIFSSMBRead(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
290 out:
291 	CIFSSMBClose(xid, tcon, fid.netfid);
292 	return rc;
293 }
294 
295 int
cifs_create_mf_symlink(unsigned int xid,struct cifs_tcon * tcon,struct cifs_sb_info * cifs_sb,const unsigned char * path,char * pbuf,unsigned int * pbytes_written)296 cifs_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
297 		       struct cifs_sb_info *cifs_sb, const unsigned char *path,
298 		       char *pbuf, unsigned int *pbytes_written)
299 {
300 	int rc;
301 	int oplock = 0;
302 	struct cifs_fid fid;
303 	struct cifs_open_parms oparms;
304 	struct cifs_io_parms io_parms = {0};
305 
306 	oparms = (struct cifs_open_parms) {
307 		.tcon = tcon,
308 		.cifs_sb = cifs_sb,
309 		.desired_access = GENERIC_WRITE,
310 		.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR),
311 		.disposition = FILE_CREATE,
312 		.path = path,
313 		.fid = &fid,
314 	};
315 
316 	rc = CIFS_open(xid, &oparms, &oplock, NULL);
317 	if (rc)
318 		return rc;
319 
320 	io_parms.netfid = fid.netfid;
321 	io_parms.pid = current->tgid;
322 	io_parms.tcon = tcon;
323 	io_parms.offset = 0;
324 	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
325 
326 	rc = CIFSSMBWrite(xid, &io_parms, pbytes_written, pbuf);
327 	CIFSSMBClose(xid, tcon, fid.netfid);
328 	return rc;
329 }
330 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
331 
332 /*
333  * SMB 2.1/SMB3 Protocol specific functions
334  */
335 int
smb3_query_mf_symlink(unsigned int xid,struct cifs_tcon * tcon,struct cifs_sb_info * cifs_sb,const unsigned char * path,char * pbuf,unsigned int * pbytes_read)336 smb3_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
337 		      struct cifs_sb_info *cifs_sb, const unsigned char *path,
338 		      char *pbuf, unsigned int *pbytes_read)
339 {
340 	int rc;
341 	struct cifs_fid fid;
342 	struct cifs_open_parms oparms;
343 	struct cifs_io_parms io_parms = {0};
344 	int buf_type = CIFS_NO_BUFFER;
345 	__le16 *utf16_path;
346 	__u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
347 	struct smb2_file_all_info *pfile_info = NULL;
348 
349 	oparms = (struct cifs_open_parms) {
350 		.tcon = tcon,
351 		.cifs_sb = cifs_sb,
352 		.path = path,
353 		.desired_access = GENERIC_READ,
354 		.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR),
355 		.disposition = FILE_OPEN,
356 		.fid = &fid,
357 	};
358 
359 	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
360 	if (utf16_path == NULL)
361 		return -ENOMEM;
362 
363 	pfile_info = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
364 			     GFP_KERNEL);
365 
366 	if (pfile_info == NULL) {
367 		kfree(utf16_path);
368 		return  -ENOMEM;
369 	}
370 
371 	rc = SMB2_open(xid, &oparms, utf16_path, &oplock, pfile_info, NULL,
372 		       NULL, NULL);
373 	if (rc)
374 		goto qmf_out_open_fail;
375 
376 	if (pfile_info->EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
377 		/* it's not a symlink */
378 		rc = -ENOENT; /* Is there a better rc to return? */
379 		goto qmf_out;
380 	}
381 
382 	io_parms.netfid = fid.netfid;
383 	io_parms.pid = current->tgid;
384 	io_parms.tcon = tcon;
385 	io_parms.offset = 0;
386 	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
387 	io_parms.persistent_fid = fid.persistent_fid;
388 	io_parms.volatile_fid = fid.volatile_fid;
389 	rc = SMB2_read(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
390 qmf_out:
391 	SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
392 qmf_out_open_fail:
393 	kfree(utf16_path);
394 	kfree(pfile_info);
395 	return rc;
396 }
397 
398 int
smb3_create_mf_symlink(unsigned int xid,struct cifs_tcon * tcon,struct cifs_sb_info * cifs_sb,const unsigned char * path,char * pbuf,unsigned int * pbytes_written)399 smb3_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
400 		       struct cifs_sb_info *cifs_sb, const unsigned char *path,
401 		       char *pbuf, unsigned int *pbytes_written)
402 {
403 	int rc;
404 	struct cifs_fid fid;
405 	struct cifs_open_parms oparms;
406 	struct cifs_io_parms io_parms = {0};
407 	__le16 *utf16_path;
408 	__u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
409 	struct kvec iov[2];
410 
411 	cifs_dbg(FYI, "%s: path: %s\n", __func__, path);
412 
413 	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
414 	if (!utf16_path)
415 		return -ENOMEM;
416 
417 	oparms = (struct cifs_open_parms) {
418 		.tcon = tcon,
419 		.cifs_sb = cifs_sb,
420 		.path = path,
421 		.desired_access = GENERIC_WRITE,
422 		.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR),
423 		.disposition = FILE_CREATE,
424 		.fid = &fid,
425 		.mode = 0644,
426 	};
427 
428 	rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL,
429 		       NULL, NULL);
430 	if (rc) {
431 		kfree(utf16_path);
432 		return rc;
433 	}
434 
435 	io_parms.netfid = fid.netfid;
436 	io_parms.pid = current->tgid;
437 	io_parms.tcon = tcon;
438 	io_parms.offset = 0;
439 	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
440 	io_parms.persistent_fid = fid.persistent_fid;
441 	io_parms.volatile_fid = fid.volatile_fid;
442 
443 	/* iov[0] is reserved for smb header */
444 	iov[1].iov_base = pbuf;
445 	iov[1].iov_len = CIFS_MF_SYMLINK_FILE_SIZE;
446 
447 	rc = SMB2_write(xid, &io_parms, pbytes_written, iov, 1);
448 
449 	/* Make sure we wrote all of the symlink data */
450 	if ((rc == 0) && (*pbytes_written != CIFS_MF_SYMLINK_FILE_SIZE))
451 		rc = -EIO;
452 
453 	SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
454 
455 	kfree(utf16_path);
456 	return rc;
457 }
458 
459 /*
460  * M-F Symlink Functions - End
461  */
462 
463 int
cifs_hardlink(struct dentry * old_file,struct inode * inode,struct dentry * direntry)464 cifs_hardlink(struct dentry *old_file, struct inode *inode,
465 	      struct dentry *direntry)
466 {
467 	int rc = -EACCES;
468 	unsigned int xid;
469 	const char *from_name, *to_name;
470 	void *page1, *page2;
471 	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
472 	struct tcon_link *tlink;
473 	struct cifs_tcon *tcon;
474 	struct TCP_Server_Info *server;
475 	struct cifsInodeInfo *cifsInode;
476 
477 	if (unlikely(cifs_forced_shutdown(cifs_sb)))
478 		return -EIO;
479 
480 	tlink = cifs_sb_tlink(cifs_sb);
481 	if (IS_ERR(tlink))
482 		return PTR_ERR(tlink);
483 	tcon = tlink_tcon(tlink);
484 
485 	xid = get_xid();
486 	page1 = alloc_dentry_path();
487 	page2 = alloc_dentry_path();
488 
489 	from_name = build_path_from_dentry(old_file, page1);
490 	if (IS_ERR(from_name)) {
491 		rc = PTR_ERR(from_name);
492 		goto cifs_hl_exit;
493 	}
494 	to_name = build_path_from_dentry(direntry, page2);
495 	if (IS_ERR(to_name)) {
496 		rc = PTR_ERR(to_name);
497 		goto cifs_hl_exit;
498 	}
499 
500 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
501 	if (tcon->unix_ext)
502 		rc = CIFSUnixCreateHardLink(xid, tcon, from_name, to_name,
503 					    cifs_sb->local_nls,
504 					    cifs_remap(cifs_sb));
505 	else {
506 #else
507 	{
508 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
509 		server = tcon->ses->server;
510 		if (!server->ops->create_hardlink) {
511 			rc = -ENOSYS;
512 			goto cifs_hl_exit;
513 		}
514 		rc = server->ops->create_hardlink(xid, tcon, old_file,
515 						  from_name, to_name, cifs_sb);
516 		if ((rc == -EIO) || (rc == -EINVAL))
517 			rc = -EOPNOTSUPP;
518 	}
519 
520 	d_drop(direntry);	/* force new lookup from server of target */
521 
522 	/*
523 	 * if source file is cached (oplocked) revalidate will not go to server
524 	 * until the file is closed or oplock broken so update nlinks locally
525 	 */
526 	if (d_really_is_positive(old_file)) {
527 		cifsInode = CIFS_I(d_inode(old_file));
528 		if (rc == 0) {
529 			spin_lock(&d_inode(old_file)->i_lock);
530 			inc_nlink(d_inode(old_file));
531 			spin_unlock(&d_inode(old_file)->i_lock);
532 
533 			/*
534 			 * parent dir timestamps will update from srv within a
535 			 * second, would it really be worth it to set the parent
536 			 * dir cifs inode time to zero to force revalidate
537 			 * (faster) for it too?
538 			 */
539 		}
540 		/*
541 		 * if not oplocked will force revalidate to get info on source
542 		 * file from srv.  Note Samba server prior to 4.2 has bug -
543 		 * not updating src file ctime on hardlinks but Windows servers
544 		 * handle it properly
545 		 */
546 		cifsInode->time = 0;
547 
548 		/*
549 		 * Will update parent dir timestamps from srv within a second.
550 		 * Would it really be worth it to set the parent dir (cifs
551 		 * inode) time field to zero to force revalidate on parent
552 		 * directory faster ie
553 		 *
554 		 * CIFS_I(inode)->time = 0;
555 		 */
556 	}
557 
558 cifs_hl_exit:
559 	free_dentry_path(page1);
560 	free_dentry_path(page2);
561 	free_xid(xid);
562 	cifs_put_tlink(tlink);
563 	return rc;
564 }
565 
566 int
567 cifs_symlink(struct mnt_idmap *idmap, struct inode *inode,
568 	     struct dentry *direntry, const char *symname)
569 {
570 	int rc = -EOPNOTSUPP;
571 	unsigned int xid;
572 	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
573 	struct TCP_Server_Info *server;
574 	struct tcon_link *tlink;
575 	struct cifs_tcon *pTcon;
576 	const char *full_path;
577 	void *page;
578 	struct inode *newinode = NULL;
579 
580 	if (unlikely(cifs_forced_shutdown(cifs_sb)))
581 		return -EIO;
582 
583 	page = alloc_dentry_path();
584 	if (!page)
585 		return -ENOMEM;
586 
587 	xid = get_xid();
588 
589 	tlink = cifs_sb_tlink(cifs_sb);
590 	if (IS_ERR(tlink)) {
591 		rc = PTR_ERR(tlink);
592 		/* BB could be clearer if skipped put_tlink on error here, but harmless */
593 		goto symlink_exit;
594 	}
595 	pTcon = tlink_tcon(tlink);
596 	server = cifs_pick_channel(pTcon->ses);
597 
598 	full_path = build_path_from_dentry(direntry, page);
599 	if (IS_ERR(full_path)) {
600 		rc = PTR_ERR(full_path);
601 		goto symlink_exit;
602 	}
603 
604 	cifs_dbg(FYI, "Full path: %s\n", full_path);
605 	cifs_dbg(FYI, "symname is %s\n", symname);
606 
607 	/* BB what if DFS and this volume is on different share? BB */
608 	rc = -EOPNOTSUPP;
609 	switch (get_cifs_symlink_type(cifs_sb)) {
610 	case CIFS_SYMLINK_TYPE_DEFAULT:
611 		/* should not happen, get_cifs_symlink_type() resolves the default */
612 		break;
613 
614 	case CIFS_SYMLINK_TYPE_NONE:
615 		break;
616 
617 	case CIFS_SYMLINK_TYPE_UNIX:
618 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
619 		if (pTcon->unix_ext) {
620 			rc = CIFSUnixCreateSymLink(xid, pTcon, full_path,
621 						   symname,
622 						   cifs_sb->local_nls,
623 						   cifs_remap(cifs_sb));
624 		}
625 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
626 		break;
627 
628 	case CIFS_SYMLINK_TYPE_MFSYMLINKS:
629 		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) {
630 			rc = create_mf_symlink(xid, pTcon, cifs_sb,
631 					       full_path, symname);
632 		}
633 		break;
634 
635 	case CIFS_SYMLINK_TYPE_SFU:
636 		if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL) {
637 			rc = __cifs_sfu_make_node(xid, inode, direntry, pTcon,
638 						  full_path, S_IFLNK,
639 						  0, symname);
640 		}
641 		break;
642 
643 	case CIFS_SYMLINK_TYPE_NATIVE:
644 	case CIFS_SYMLINK_TYPE_NFS:
645 	case CIFS_SYMLINK_TYPE_WSL:
646 		if (server->ops->create_reparse_symlink) {
647 			rc = server->ops->create_reparse_symlink(xid, inode,
648 								 direntry,
649 								 pTcon,
650 								 full_path,
651 								 symname);
652 			goto symlink_exit;
653 		}
654 		break;
655 	}
656 
657 	if (rc == 0) {
658 		if (pTcon->posix_extensions) {
659 			rc = smb311_posix_get_inode_info(&newinode, full_path,
660 							 NULL, inode->i_sb, xid);
661 		} else if (pTcon->unix_ext) {
662 			rc = cifs_get_inode_info_unix(&newinode, full_path,
663 						      inode->i_sb, xid);
664 		} else {
665 			rc = cifs_get_inode_info(&newinode, full_path, NULL,
666 						 inode->i_sb, xid, NULL);
667 		}
668 
669 		if (rc != 0) {
670 			cifs_dbg(FYI, "Create symlink ok, getinodeinfo fail rc = %d\n",
671 				 rc);
672 		} else {
673 			d_instantiate(direntry, newinode);
674 		}
675 	}
676 symlink_exit:
677 	free_dentry_path(page);
678 	cifs_put_tlink(tlink);
679 	free_xid(xid);
680 	return rc;
681 }
682