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v6.2
  1// SPDX-License-Identifier: LGPL-2.1
  2/*
 
  3 *
  4 *   Copyright (C) International Business Machines  Corp., 2002,2008
  5 *   Author(s): Steve French (sfrench@us.ibm.com)
  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
 22/*
 23 * M-F Symlink Functions - Begin
 24 */
 25
 26#define CIFS_MF_SYMLINK_LEN_OFFSET (4+1)
 27#define CIFS_MF_SYMLINK_MD5_OFFSET (CIFS_MF_SYMLINK_LEN_OFFSET+(4+1))
 28#define CIFS_MF_SYMLINK_LINK_OFFSET (CIFS_MF_SYMLINK_MD5_OFFSET+(32+1))
 29#define CIFS_MF_SYMLINK_LINK_MAXLEN (1024)
 30#define CIFS_MF_SYMLINK_FILE_SIZE \
 31	(CIFS_MF_SYMLINK_LINK_OFFSET + CIFS_MF_SYMLINK_LINK_MAXLEN)
 32
 33#define CIFS_MF_SYMLINK_LEN_FORMAT "XSym\n%04u\n"
 34#define CIFS_MF_SYMLINK_MD5_FORMAT "%16phN\n"
 35#define CIFS_MF_SYMLINK_MD5_ARGS(md5_hash) md5_hash
 36
 37static int
 38symlink_hash(unsigned int link_len, const char *link_str, u8 *md5_hash)
 39{
 40	int rc;
 41	struct shash_desc *md5 = NULL;
 
 42
 43	rc = cifs_alloc_hash("md5", &md5);
 44	if (rc)
 45		goto symlink_hash_err;
 46
 47	rc = crypto_shash_init(md5);
 48	if (rc) {
 49		cifs_dbg(VFS, "%s: Could not init md5 shash\n", __func__);
 50		goto symlink_hash_err;
 51	}
 52	rc = crypto_shash_update(md5, link_str, link_len);
 53	if (rc) {
 54		cifs_dbg(VFS, "%s: Could not update with link_str\n", __func__);
 55		goto symlink_hash_err;
 56	}
 57	rc = crypto_shash_final(md5, md5_hash);
 58	if (rc)
 59		cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 60
 61symlink_hash_err:
 62	cifs_free_hash(&md5);
 63	return rc;
 64}
 65
 66static int
 67parse_mf_symlink(const u8 *buf, unsigned int buf_len, unsigned int *_link_len,
 68		 char **_link_str)
 69{
 70	int rc;
 71	unsigned int link_len;
 72	const char *md5_str1;
 73	const char *link_str;
 74	u8 md5_hash[16];
 75	char md5_str2[34];
 76
 77	if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
 78		return -EINVAL;
 79
 80	md5_str1 = (const char *)&buf[CIFS_MF_SYMLINK_MD5_OFFSET];
 81	link_str = (const char *)&buf[CIFS_MF_SYMLINK_LINK_OFFSET];
 82
 83	rc = sscanf(buf, CIFS_MF_SYMLINK_LEN_FORMAT, &link_len);
 84	if (rc != 1)
 85		return -EINVAL;
 86
 87	if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
 88		return -EINVAL;
 89
 90	rc = symlink_hash(link_len, link_str, md5_hash);
 91	if (rc) {
 92		cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);
 93		return rc;
 94	}
 95
 96	scnprintf(md5_str2, sizeof(md5_str2),
 97		  CIFS_MF_SYMLINK_MD5_FORMAT,
 98		  CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
 99
100	if (strncmp(md5_str1, md5_str2, 17) != 0)
101		return -EINVAL;
102
103	if (_link_str) {
104		*_link_str = kstrndup(link_str, link_len, GFP_KERNEL);
105		if (!*_link_str)
106			return -ENOMEM;
107	}
108
109	*_link_len = link_len;
110	return 0;
111}
112
113static int
114format_mf_symlink(u8 *buf, unsigned int buf_len, const char *link_str)
115{
116	int rc;
117	unsigned int link_len;
118	unsigned int ofs;
119	u8 md5_hash[16];
120
121	if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
122		return -EINVAL;
123
124	link_len = strlen(link_str);
125
126	if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
127		return -ENAMETOOLONG;
128
129	rc = symlink_hash(link_len, link_str, md5_hash);
130	if (rc) {
131		cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);
132		return rc;
133	}
134
135	scnprintf(buf, buf_len,
136		  CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT,
137		  link_len,
138		  CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
139
140	ofs = CIFS_MF_SYMLINK_LINK_OFFSET;
141	memcpy(buf + ofs, link_str, link_len);
142
143	ofs += link_len;
144	if (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
145		buf[ofs] = '\n';
146		ofs++;
147	}
148
149	while (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
150		buf[ofs] = ' ';
151		ofs++;
152	}
153
154	return 0;
155}
156
157bool
158couldbe_mf_symlink(const struct cifs_fattr *fattr)
159{
160	if (!S_ISREG(fattr->cf_mode))
161		/* it's not a symlink */
162		return false;
163
164	if (fattr->cf_eof != CIFS_MF_SYMLINK_FILE_SIZE)
165		/* it's not a symlink */
166		return false;
167
168	return true;
169}
170
171static int
172create_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon,
173		  struct cifs_sb_info *cifs_sb, const char *fromName,
174		  const char *toName)
175{
176	int rc;
177	u8 *buf;
178	unsigned int bytes_written = 0;
179
180	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
181	if (!buf)
182		return -ENOMEM;
183
184	rc = format_mf_symlink(buf, CIFS_MF_SYMLINK_FILE_SIZE, toName);
185	if (rc)
186		goto out;
187
188	if (tcon->ses->server->ops->create_mf_symlink)
189		rc = tcon->ses->server->ops->create_mf_symlink(xid, tcon,
190					cifs_sb, fromName, buf, &bytes_written);
191	else
192		rc = -EOPNOTSUPP;
193
194	if (rc)
195		goto out;
196
197	if (bytes_written != CIFS_MF_SYMLINK_FILE_SIZE)
198		rc = -EIO;
199out:
200	kfree(buf);
201	return rc;
202}
203
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
204int
205check_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
206		 struct cifs_sb_info *cifs_sb, struct cifs_fattr *fattr,
207		 const unsigned char *path)
208{
209	int rc;
210	u8 *buf = NULL;
211	unsigned int link_len = 0;
212	unsigned int bytes_read = 0;
213	char *symlink = NULL;
214
215	if (!couldbe_mf_symlink(fattr))
216		/* it's not a symlink */
217		return 0;
218
219	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
220	if (!buf)
221		return -ENOMEM;
222
223	if (tcon->ses->server->ops->query_mf_symlink)
224		rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon,
225					      cifs_sb, path, buf, &bytes_read);
226	else
227		rc = -ENOSYS;
228
229	if (rc)
230		goto out;
231
232	if (bytes_read == 0) /* not a symlink */
233		goto out;
234
235	rc = parse_mf_symlink(buf, bytes_read, &link_len, &symlink);
236	if (rc == -EINVAL) {
237		/* it's not a symlink */
238		rc = 0;
239		goto out;
240	}
241
242	if (rc != 0)
243		goto out;
244
245	/* it is a symlink */
246	fattr->cf_eof = link_len;
247	fattr->cf_mode &= ~S_IFMT;
248	fattr->cf_mode |= S_IFLNK | S_IRWXU | S_IRWXG | S_IRWXO;
249	fattr->cf_dtype = DT_LNK;
250	fattr->cf_symlink_target = symlink;
251out:
252	kfree(buf);
253	return rc;
254}
255
256#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
257/*
258 * SMB 1.0 Protocol specific functions
259 */
260
261int
262cifs_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
263		      struct cifs_sb_info *cifs_sb, const unsigned char *path,
264		      char *pbuf, unsigned int *pbytes_read)
265{
266	int rc;
267	int oplock = 0;
268	struct cifs_fid fid;
269	struct cifs_open_parms oparms;
270	struct cifs_io_parms io_parms = {0};
271	int buf_type = CIFS_NO_BUFFER;
272	FILE_ALL_INFO file_info;
273
274	oparms.tcon = tcon;
275	oparms.cifs_sb = cifs_sb;
276	oparms.desired_access = GENERIC_READ;
277	oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
278	oparms.disposition = FILE_OPEN;
279	oparms.path = path;
280	oparms.fid = &fid;
281	oparms.reconnect = false;
282
283	rc = CIFS_open(xid, &oparms, &oplock, &file_info);
284	if (rc)
285		return rc;
286
287	if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
288		rc = -ENOENT;
289		/* it's not a symlink */
290		goto out;
291	}
292
293	io_parms.netfid = fid.netfid;
294	io_parms.pid = current->tgid;
295	io_parms.tcon = tcon;
296	io_parms.offset = 0;
297	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
298
299	rc = CIFSSMBRead(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
300out:
301	CIFSSMBClose(xid, tcon, fid.netfid);
302	return rc;
303}
304
305int
306cifs_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
307		       struct cifs_sb_info *cifs_sb, const unsigned char *path,
308		       char *pbuf, unsigned int *pbytes_written)
309{
310	int rc;
311	int oplock = 0;
312	struct cifs_fid fid;
313	struct cifs_open_parms oparms;
314	struct cifs_io_parms io_parms = {0};
315
316	oparms.tcon = tcon;
317	oparms.cifs_sb = cifs_sb;
318	oparms.desired_access = GENERIC_WRITE;
319	oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
320	oparms.disposition = FILE_CREATE;
321	oparms.path = path;
322	oparms.fid = &fid;
323	oparms.reconnect = false;
324
325	rc = CIFS_open(xid, &oparms, &oplock, NULL);
326	if (rc)
327		return rc;
328
329	io_parms.netfid = fid.netfid;
330	io_parms.pid = current->tgid;
331	io_parms.tcon = tcon;
332	io_parms.offset = 0;
333	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
334
335	rc = CIFSSMBWrite(xid, &io_parms, pbytes_written, pbuf);
336	CIFSSMBClose(xid, tcon, fid.netfid);
337	return rc;
338}
339#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
340
341/*
342 * SMB 2.1/SMB3 Protocol specific functions
343 */
344int
345smb3_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
346		      struct cifs_sb_info *cifs_sb, const unsigned char *path,
347		      char *pbuf, unsigned int *pbytes_read)
348{
349	int rc;
350	struct cifs_fid fid;
351	struct cifs_open_parms oparms;
352	struct cifs_io_parms io_parms = {0};
353	int buf_type = CIFS_NO_BUFFER;
354	__le16 *utf16_path;
355	__u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
356	struct smb2_file_all_info *pfile_info = NULL;
357
358	oparms.tcon = tcon;
359	oparms.cifs_sb = cifs_sb;
360	oparms.desired_access = GENERIC_READ;
361	oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
362	oparms.disposition = FILE_OPEN;
363	oparms.fid = &fid;
364	oparms.reconnect = false;
365
366	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
367	if (utf16_path == NULL)
368		return -ENOMEM;
369
370	pfile_info = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
371			     GFP_KERNEL);
372
373	if (pfile_info == NULL) {
374		kfree(utf16_path);
375		return  -ENOMEM;
376	}
377
378	rc = SMB2_open(xid, &oparms, utf16_path, &oplock, pfile_info, NULL,
379		       NULL, NULL);
380	if (rc)
381		goto qmf_out_open_fail;
382
383	if (pfile_info->EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
384		/* it's not a symlink */
385		rc = -ENOENT; /* Is there a better rc to return? */
386		goto qmf_out;
387	}
388
389	io_parms.netfid = fid.netfid;
390	io_parms.pid = current->tgid;
391	io_parms.tcon = tcon;
392	io_parms.offset = 0;
393	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
394	io_parms.persistent_fid = fid.persistent_fid;
395	io_parms.volatile_fid = fid.volatile_fid;
396	rc = SMB2_read(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
397qmf_out:
398	SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
399qmf_out_open_fail:
400	kfree(utf16_path);
401	kfree(pfile_info);
402	return rc;
403}
404
405int
406smb3_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
407		       struct cifs_sb_info *cifs_sb, const unsigned char *path,
408		       char *pbuf, unsigned int *pbytes_written)
409{
410	int rc;
411	struct cifs_fid fid;
412	struct cifs_open_parms oparms;
413	struct cifs_io_parms io_parms = {0};
414	__le16 *utf16_path;
415	__u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
416	struct kvec iov[2];
417
418	cifs_dbg(FYI, "%s: path: %s\n", __func__, path);
419
420	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
421	if (!utf16_path)
422		return -ENOMEM;
423
424	oparms.tcon = tcon;
425	oparms.cifs_sb = cifs_sb;
426	oparms.desired_access = GENERIC_WRITE;
427	oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
428	oparms.disposition = FILE_CREATE;
429	oparms.fid = &fid;
430	oparms.reconnect = false;
431	oparms.mode = 0644;
432
433	rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL,
434		       NULL, NULL);
435	if (rc) {
436		kfree(utf16_path);
437		return rc;
438	}
439
440	io_parms.netfid = fid.netfid;
441	io_parms.pid = current->tgid;
442	io_parms.tcon = tcon;
443	io_parms.offset = 0;
444	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
445	io_parms.persistent_fid = fid.persistent_fid;
446	io_parms.volatile_fid = fid.volatile_fid;
447
448	/* iov[0] is reserved for smb header */
449	iov[1].iov_base = pbuf;
450	iov[1].iov_len = CIFS_MF_SYMLINK_FILE_SIZE;
451
452	rc = SMB2_write(xid, &io_parms, pbytes_written, iov, 1);
453
454	/* Make sure we wrote all of the symlink data */
455	if ((rc == 0) && (*pbytes_written != CIFS_MF_SYMLINK_FILE_SIZE))
456		rc = -EIO;
457
458	SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
459
460	kfree(utf16_path);
461	return rc;
462}
463
464/*
465 * M-F Symlink Functions - End
466 */
467
468int
469cifs_hardlink(struct dentry *old_file, struct inode *inode,
470	      struct dentry *direntry)
471{
472	int rc = -EACCES;
473	unsigned int xid;
474	const char *from_name, *to_name;
475	void *page1, *page2;
476	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
477	struct tcon_link *tlink;
478	struct cifs_tcon *tcon;
479	struct TCP_Server_Info *server;
480	struct cifsInodeInfo *cifsInode;
481
482	if (unlikely(cifs_forced_shutdown(cifs_sb)))
483		return -EIO;
484
485	tlink = cifs_sb_tlink(cifs_sb);
486	if (IS_ERR(tlink))
487		return PTR_ERR(tlink);
488	tcon = tlink_tcon(tlink);
489
490	xid = get_xid();
491	page1 = alloc_dentry_path();
492	page2 = alloc_dentry_path();
493
494	from_name = build_path_from_dentry(old_file, page1);
495	if (IS_ERR(from_name)) {
496		rc = PTR_ERR(from_name);
497		goto cifs_hl_exit;
498	}
499	to_name = build_path_from_dentry(direntry, page2);
500	if (IS_ERR(to_name)) {
501		rc = PTR_ERR(to_name);
502		goto cifs_hl_exit;
503	}
504
505#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
506	if (tcon->unix_ext)
507		rc = CIFSUnixCreateHardLink(xid, tcon, from_name, to_name,
508					    cifs_sb->local_nls,
509					    cifs_remap(cifs_sb));
510	else {
511#else
512	{
513#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
514		server = tcon->ses->server;
515		if (!server->ops->create_hardlink) {
516			rc = -ENOSYS;
517			goto cifs_hl_exit;
518		}
519		rc = server->ops->create_hardlink(xid, tcon, from_name, to_name,
520						  cifs_sb);
521		if ((rc == -EIO) || (rc == -EINVAL))
522			rc = -EOPNOTSUPP;
523	}
524
525	d_drop(direntry);	/* force new lookup from server of target */
526
527	/*
528	 * if source file is cached (oplocked) revalidate will not go to server
529	 * until the file is closed or oplock broken so update nlinks locally
530	 */
531	if (d_really_is_positive(old_file)) {
532		cifsInode = CIFS_I(d_inode(old_file));
533		if (rc == 0) {
534			spin_lock(&d_inode(old_file)->i_lock);
535			inc_nlink(d_inode(old_file));
536			spin_unlock(&d_inode(old_file)->i_lock);
537
538			/*
539			 * parent dir timestamps will update from srv within a
540			 * second, would it really be worth it to set the parent
541			 * dir cifs inode time to zero to force revalidate
542			 * (faster) for it too?
543			 */
544		}
545		/*
546		 * if not oplocked will force revalidate to get info on source
547		 * file from srv.  Note Samba server prior to 4.2 has bug -
548		 * not updating src file ctime on hardlinks but Windows servers
549		 * handle it properly
550		 */
551		cifsInode->time = 0;
552
553		/*
554		 * Will update parent dir timestamps from srv within a second.
555		 * Would it really be worth it to set the parent dir (cifs
556		 * inode) time field to zero to force revalidate on parent
557		 * directory faster ie
558		 *
559		 * CIFS_I(inode)->time = 0;
560		 */
561	}
562
563cifs_hl_exit:
564	free_dentry_path(page1);
565	free_dentry_path(page2);
566	free_xid(xid);
567	cifs_put_tlink(tlink);
568	return rc;
569}
570
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
571int
572cifs_symlink(struct user_namespace *mnt_userns, struct inode *inode,
573	     struct dentry *direntry, const char *symname)
574{
575	int rc = -EOPNOTSUPP;
576	unsigned int xid;
577	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
578	struct tcon_link *tlink;
579	struct cifs_tcon *pTcon;
580	const char *full_path;
581	void *page;
582	struct inode *newinode = NULL;
583
584	if (unlikely(cifs_forced_shutdown(cifs_sb)))
585		return -EIO;
586
587	page = alloc_dentry_path();
588	if (!page)
589		return -ENOMEM;
590
591	xid = get_xid();
592
593	tlink = cifs_sb_tlink(cifs_sb);
594	if (IS_ERR(tlink)) {
595		rc = PTR_ERR(tlink);
596		goto symlink_exit;
597	}
598	pTcon = tlink_tcon(tlink);
599
600	full_path = build_path_from_dentry(direntry, page);
601	if (IS_ERR(full_path)) {
602		rc = PTR_ERR(full_path);
603		goto symlink_exit;
604	}
605
606	cifs_dbg(FYI, "Full path: %s\n", full_path);
607	cifs_dbg(FYI, "symname is %s\n", symname);
608
609	/* BB what if DFS and this volume is on different share? BB */
610	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
611		rc = create_mf_symlink(xid, pTcon, cifs_sb, full_path, symname);
612#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
613	else if (pTcon->unix_ext)
614		rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname,
615					   cifs_sb->local_nls,
616					   cifs_remap(cifs_sb));
617#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
618	/* else
619	   rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName,
620					cifs_sb_target->local_nls); */
621
622	if (rc == 0) {
623		if (pTcon->posix_extensions)
624			rc = smb311_posix_get_inode_info(&newinode, full_path, inode->i_sb, xid);
625		else if (pTcon->unix_ext)
626			rc = cifs_get_inode_info_unix(&newinode, full_path,
627						      inode->i_sb, xid);
628		else
629			rc = cifs_get_inode_info(&newinode, full_path, NULL,
630						 inode->i_sb, xid, NULL);
631
632		if (rc != 0) {
633			cifs_dbg(FYI, "Create symlink ok, getinodeinfo fail rc = %d\n",
634				 rc);
635		} else {
636			d_instantiate(direntry, newinode);
637		}
638	}
639symlink_exit:
640	free_dentry_path(page);
641	cifs_put_tlink(tlink);
642	free_xid(xid);
643	return rc;
644}
v5.14.15
  1// SPDX-License-Identifier: LGPL-2.1
  2/*
  3 *   fs/cifs/link.c
  4 *
  5 *   Copyright (C) International Business Machines  Corp., 2002,2008
  6 *   Author(s): Steve French (sfrench@us.ibm.com)
  7 *
  8 */
  9#include <linux/fs.h>
 10#include <linux/stat.h>
 11#include <linux/slab.h>
 12#include <linux/namei.h>
 13#include "cifsfs.h"
 14#include "cifspdu.h"
 15#include "cifsglob.h"
 16#include "cifsproto.h"
 17#include "cifs_debug.h"
 18#include "cifs_fs_sb.h"
 19#include "cifs_unicode.h"
 20#include "smb2proto.h"
 21#include "cifs_ioctl.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
 38static int
 39symlink_hash(unsigned int link_len, const char *link_str, u8 *md5_hash)
 40{
 41	int rc;
 42	struct crypto_shash *md5 = NULL;
 43	struct sdesc *sdescmd5 = NULL;
 44
 45	rc = cifs_alloc_hash("md5", &md5, &sdescmd5);
 46	if (rc)
 47		goto symlink_hash_err;
 48
 49	rc = crypto_shash_init(&sdescmd5->shash);
 50	if (rc) {
 51		cifs_dbg(VFS, "%s: Could not init md5 shash\n", __func__);
 52		goto symlink_hash_err;
 53	}
 54	rc = crypto_shash_update(&sdescmd5->shash, link_str, link_len);
 55	if (rc) {
 56		cifs_dbg(VFS, "%s: Could not update with link_str\n", __func__);
 57		goto symlink_hash_err;
 58	}
 59	rc = crypto_shash_final(&sdescmd5->shash, md5_hash);
 60	if (rc)
 61		cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
 62
 63symlink_hash_err:
 64	cifs_free_hash(&md5, &sdescmd5);
 65	return rc;
 66}
 67
 68static int
 69parse_mf_symlink(const u8 *buf, unsigned int buf_len, unsigned int *_link_len,
 70		 char **_link_str)
 71{
 72	int rc;
 73	unsigned int link_len;
 74	const char *md5_str1;
 75	const char *link_str;
 76	u8 md5_hash[16];
 77	char md5_str2[34];
 78
 79	if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
 80		return -EINVAL;
 81
 82	md5_str1 = (const char *)&buf[CIFS_MF_SYMLINK_MD5_OFFSET];
 83	link_str = (const char *)&buf[CIFS_MF_SYMLINK_LINK_OFFSET];
 84
 85	rc = sscanf(buf, CIFS_MF_SYMLINK_LEN_FORMAT, &link_len);
 86	if (rc != 1)
 87		return -EINVAL;
 88
 
 
 
 89	rc = symlink_hash(link_len, link_str, md5_hash);
 90	if (rc) {
 91		cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);
 92		return rc;
 93	}
 94
 95	scnprintf(md5_str2, sizeof(md5_str2),
 96		  CIFS_MF_SYMLINK_MD5_FORMAT,
 97		  CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
 98
 99	if (strncmp(md5_str1, md5_str2, 17) != 0)
100		return -EINVAL;
101
102	if (_link_str) {
103		*_link_str = kstrndup(link_str, link_len, GFP_KERNEL);
104		if (!*_link_str)
105			return -ENOMEM;
106	}
107
108	*_link_len = link_len;
109	return 0;
110}
111
112static int
113format_mf_symlink(u8 *buf, unsigned int buf_len, const char *link_str)
114{
115	int rc;
116	unsigned int link_len;
117	unsigned int ofs;
118	u8 md5_hash[16];
119
120	if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
121		return -EINVAL;
122
123	link_len = strlen(link_str);
124
125	if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
126		return -ENAMETOOLONG;
127
128	rc = symlink_hash(link_len, link_str, md5_hash);
129	if (rc) {
130		cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);
131		return rc;
132	}
133
134	scnprintf(buf, buf_len,
135		  CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT,
136		  link_len,
137		  CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
138
139	ofs = CIFS_MF_SYMLINK_LINK_OFFSET;
140	memcpy(buf + ofs, link_str, link_len);
141
142	ofs += link_len;
143	if (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
144		buf[ofs] = '\n';
145		ofs++;
146	}
147
148	while (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
149		buf[ofs] = ' ';
150		ofs++;
151	}
152
153	return 0;
154}
155
156bool
157couldbe_mf_symlink(const struct cifs_fattr *fattr)
158{
159	if (!S_ISREG(fattr->cf_mode))
160		/* it's not a symlink */
161		return false;
162
163	if (fattr->cf_eof != CIFS_MF_SYMLINK_FILE_SIZE)
164		/* it's not a symlink */
165		return false;
166
167	return true;
168}
169
170static int
171create_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon,
172		  struct cifs_sb_info *cifs_sb, const char *fromName,
173		  const char *toName)
174{
175	int rc;
176	u8 *buf;
177	unsigned int bytes_written = 0;
178
179	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
180	if (!buf)
181		return -ENOMEM;
182
183	rc = format_mf_symlink(buf, CIFS_MF_SYMLINK_FILE_SIZE, toName);
184	if (rc)
185		goto out;
186
187	if (tcon->ses->server->ops->create_mf_symlink)
188		rc = tcon->ses->server->ops->create_mf_symlink(xid, tcon,
189					cifs_sb, fromName, buf, &bytes_written);
190	else
191		rc = -EOPNOTSUPP;
192
193	if (rc)
194		goto out;
195
196	if (bytes_written != CIFS_MF_SYMLINK_FILE_SIZE)
197		rc = -EIO;
198out:
199	kfree(buf);
200	return rc;
201}
202
203static int
204query_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon,
205		 struct cifs_sb_info *cifs_sb, const unsigned char *path,
206		 char **symlinkinfo)
207{
208	int rc;
209	u8 *buf = NULL;
210	unsigned int link_len = 0;
211	unsigned int bytes_read = 0;
212
213	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
214	if (!buf)
215		return -ENOMEM;
216
217	if (tcon->ses->server->ops->query_mf_symlink)
218		rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon,
219					      cifs_sb, path, buf, &bytes_read);
220	else
221		rc = -ENOSYS;
222
223	if (rc)
224		goto out;
225
226	if (bytes_read == 0) { /* not a symlink */
227		rc = -EINVAL;
228		goto out;
229	}
230
231	rc = parse_mf_symlink(buf, bytes_read, &link_len, symlinkinfo);
232out:
233	kfree(buf);
234	return rc;
235}
236
237int
238check_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
239		 struct cifs_sb_info *cifs_sb, struct cifs_fattr *fattr,
240		 const unsigned char *path)
241{
242	int rc;
243	u8 *buf = NULL;
244	unsigned int link_len = 0;
245	unsigned int bytes_read = 0;
 
246
247	if (!couldbe_mf_symlink(fattr))
248		/* it's not a symlink */
249		return 0;
250
251	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
252	if (!buf)
253		return -ENOMEM;
254
255	if (tcon->ses->server->ops->query_mf_symlink)
256		rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon,
257					      cifs_sb, path, buf, &bytes_read);
258	else
259		rc = -ENOSYS;
260
261	if (rc)
262		goto out;
263
264	if (bytes_read == 0) /* not a symlink */
265		goto out;
266
267	rc = parse_mf_symlink(buf, bytes_read, &link_len, NULL);
268	if (rc == -EINVAL) {
269		/* it's not a symlink */
270		rc = 0;
271		goto out;
272	}
273
274	if (rc != 0)
275		goto out;
276
277	/* it is a symlink */
278	fattr->cf_eof = link_len;
279	fattr->cf_mode &= ~S_IFMT;
280	fattr->cf_mode |= S_IFLNK | S_IRWXU | S_IRWXG | S_IRWXO;
281	fattr->cf_dtype = DT_LNK;
 
282out:
283	kfree(buf);
284	return rc;
285}
286
 
287/*
288 * SMB 1.0 Protocol specific functions
289 */
290
291int
292cifs_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
293		      struct cifs_sb_info *cifs_sb, const unsigned char *path,
294		      char *pbuf, unsigned int *pbytes_read)
295{
296	int rc;
297	int oplock = 0;
298	struct cifs_fid fid;
299	struct cifs_open_parms oparms;
300	struct cifs_io_parms io_parms = {0};
301	int buf_type = CIFS_NO_BUFFER;
302	FILE_ALL_INFO file_info;
303
304	oparms.tcon = tcon;
305	oparms.cifs_sb = cifs_sb;
306	oparms.desired_access = GENERIC_READ;
307	oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
308	oparms.disposition = FILE_OPEN;
309	oparms.path = path;
310	oparms.fid = &fid;
311	oparms.reconnect = false;
312
313	rc = CIFS_open(xid, &oparms, &oplock, &file_info);
314	if (rc)
315		return rc;
316
317	if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
318		rc = -ENOENT;
319		/* it's not a symlink */
320		goto out;
321	}
322
323	io_parms.netfid = fid.netfid;
324	io_parms.pid = current->tgid;
325	io_parms.tcon = tcon;
326	io_parms.offset = 0;
327	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
328
329	rc = CIFSSMBRead(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
330out:
331	CIFSSMBClose(xid, tcon, fid.netfid);
332	return rc;
333}
334
335int
336cifs_create_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_written)
339{
340	int rc;
341	int oplock = 0;
342	struct cifs_fid fid;
343	struct cifs_open_parms oparms;
344	struct cifs_io_parms io_parms = {0};
345
346	oparms.tcon = tcon;
347	oparms.cifs_sb = cifs_sb;
348	oparms.desired_access = GENERIC_WRITE;
349	oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
350	oparms.disposition = FILE_CREATE;
351	oparms.path = path;
352	oparms.fid = &fid;
353	oparms.reconnect = false;
354
355	rc = CIFS_open(xid, &oparms, &oplock, NULL);
356	if (rc)
357		return rc;
358
359	io_parms.netfid = fid.netfid;
360	io_parms.pid = current->tgid;
361	io_parms.tcon = tcon;
362	io_parms.offset = 0;
363	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
364
365	rc = CIFSSMBWrite(xid, &io_parms, pbytes_written, pbuf);
366	CIFSSMBClose(xid, tcon, fid.netfid);
367	return rc;
368}
 
369
370/*
371 * SMB 2.1/SMB3 Protocol specific functions
372 */
373int
374smb3_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
375		      struct cifs_sb_info *cifs_sb, const unsigned char *path,
376		      char *pbuf, unsigned int *pbytes_read)
377{
378	int rc;
379	struct cifs_fid fid;
380	struct cifs_open_parms oparms;
381	struct cifs_io_parms io_parms = {0};
382	int buf_type = CIFS_NO_BUFFER;
383	__le16 *utf16_path;
384	__u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
385	struct smb2_file_all_info *pfile_info = NULL;
386
387	oparms.tcon = tcon;
388	oparms.cifs_sb = cifs_sb;
389	oparms.desired_access = GENERIC_READ;
390	oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
391	oparms.disposition = FILE_OPEN;
392	oparms.fid = &fid;
393	oparms.reconnect = false;
394
395	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
396	if (utf16_path == NULL)
397		return -ENOMEM;
398
399	pfile_info = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
400			     GFP_KERNEL);
401
402	if (pfile_info == NULL) {
403		kfree(utf16_path);
404		return  -ENOMEM;
405	}
406
407	rc = SMB2_open(xid, &oparms, utf16_path, &oplock, pfile_info, NULL,
408		       NULL, NULL);
409	if (rc)
410		goto qmf_out_open_fail;
411
412	if (pfile_info->EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
413		/* it's not a symlink */
414		rc = -ENOENT; /* Is there a better rc to return? */
415		goto qmf_out;
416	}
417
418	io_parms.netfid = fid.netfid;
419	io_parms.pid = current->tgid;
420	io_parms.tcon = tcon;
421	io_parms.offset = 0;
422	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
423	io_parms.persistent_fid = fid.persistent_fid;
424	io_parms.volatile_fid = fid.volatile_fid;
425	rc = SMB2_read(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
426qmf_out:
427	SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
428qmf_out_open_fail:
429	kfree(utf16_path);
430	kfree(pfile_info);
431	return rc;
432}
433
434int
435smb3_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
436		       struct cifs_sb_info *cifs_sb, const unsigned char *path,
437		       char *pbuf, unsigned int *pbytes_written)
438{
439	int rc;
440	struct cifs_fid fid;
441	struct cifs_open_parms oparms;
442	struct cifs_io_parms io_parms = {0};
443	__le16 *utf16_path;
444	__u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
445	struct kvec iov[2];
446
447	cifs_dbg(FYI, "%s: path: %s\n", __func__, path);
448
449	utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
450	if (!utf16_path)
451		return -ENOMEM;
452
453	oparms.tcon = tcon;
454	oparms.cifs_sb = cifs_sb;
455	oparms.desired_access = GENERIC_WRITE;
456	oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
457	oparms.disposition = FILE_CREATE;
458	oparms.fid = &fid;
459	oparms.reconnect = false;
 
460
461	rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL,
462		       NULL, NULL);
463	if (rc) {
464		kfree(utf16_path);
465		return rc;
466	}
467
468	io_parms.netfid = fid.netfid;
469	io_parms.pid = current->tgid;
470	io_parms.tcon = tcon;
471	io_parms.offset = 0;
472	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
473	io_parms.persistent_fid = fid.persistent_fid;
474	io_parms.volatile_fid = fid.volatile_fid;
475
476	/* iov[0] is reserved for smb header */
477	iov[1].iov_base = pbuf;
478	iov[1].iov_len = CIFS_MF_SYMLINK_FILE_SIZE;
479
480	rc = SMB2_write(xid, &io_parms, pbytes_written, iov, 1);
481
482	/* Make sure we wrote all of the symlink data */
483	if ((rc == 0) && (*pbytes_written != CIFS_MF_SYMLINK_FILE_SIZE))
484		rc = -EIO;
485
486	SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
487
488	kfree(utf16_path);
489	return rc;
490}
491
492/*
493 * M-F Symlink Functions - End
494 */
495
496int
497cifs_hardlink(struct dentry *old_file, struct inode *inode,
498	      struct dentry *direntry)
499{
500	int rc = -EACCES;
501	unsigned int xid;
502	const char *from_name, *to_name;
503	void *page1, *page2;
504	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
505	struct tcon_link *tlink;
506	struct cifs_tcon *tcon;
507	struct TCP_Server_Info *server;
508	struct cifsInodeInfo *cifsInode;
509
510	if (unlikely(cifs_forced_shutdown(cifs_sb)))
511		return -EIO;
512
513	tlink = cifs_sb_tlink(cifs_sb);
514	if (IS_ERR(tlink))
515		return PTR_ERR(tlink);
516	tcon = tlink_tcon(tlink);
517
518	xid = get_xid();
519	page1 = alloc_dentry_path();
520	page2 = alloc_dentry_path();
521
522	from_name = build_path_from_dentry(old_file, page1);
523	if (IS_ERR(from_name)) {
524		rc = PTR_ERR(from_name);
525		goto cifs_hl_exit;
526	}
527	to_name = build_path_from_dentry(direntry, page2);
528	if (IS_ERR(to_name)) {
529		rc = PTR_ERR(to_name);
530		goto cifs_hl_exit;
531	}
532
 
533	if (tcon->unix_ext)
534		rc = CIFSUnixCreateHardLink(xid, tcon, from_name, to_name,
535					    cifs_sb->local_nls,
536					    cifs_remap(cifs_sb));
537	else {
 
 
 
538		server = tcon->ses->server;
539		if (!server->ops->create_hardlink) {
540			rc = -ENOSYS;
541			goto cifs_hl_exit;
542		}
543		rc = server->ops->create_hardlink(xid, tcon, from_name, to_name,
544						  cifs_sb);
545		if ((rc == -EIO) || (rc == -EINVAL))
546			rc = -EOPNOTSUPP;
547	}
548
549	d_drop(direntry);	/* force new lookup from server of target */
550
551	/*
552	 * if source file is cached (oplocked) revalidate will not go to server
553	 * until the file is closed or oplock broken so update nlinks locally
554	 */
555	if (d_really_is_positive(old_file)) {
556		cifsInode = CIFS_I(d_inode(old_file));
557		if (rc == 0) {
558			spin_lock(&d_inode(old_file)->i_lock);
559			inc_nlink(d_inode(old_file));
560			spin_unlock(&d_inode(old_file)->i_lock);
561
562			/*
563			 * parent dir timestamps will update from srv within a
564			 * second, would it really be worth it to set the parent
565			 * dir cifs inode time to zero to force revalidate
566			 * (faster) for it too?
567			 */
568		}
569		/*
570		 * if not oplocked will force revalidate to get info on source
571		 * file from srv.  Note Samba server prior to 4.2 has bug -
572		 * not updating src file ctime on hardlinks but Windows servers
573		 * handle it properly
574		 */
575		cifsInode->time = 0;
576
577		/*
578		 * Will update parent dir timestamps from srv within a second.
579		 * Would it really be worth it to set the parent dir (cifs
580		 * inode) time field to zero to force revalidate on parent
581		 * directory faster ie
582		 *
583		 * CIFS_I(inode)->time = 0;
584		 */
585	}
586
587cifs_hl_exit:
588	free_dentry_path(page1);
589	free_dentry_path(page2);
590	free_xid(xid);
591	cifs_put_tlink(tlink);
592	return rc;
593}
594
595const char *
596cifs_get_link(struct dentry *direntry, struct inode *inode,
597	      struct delayed_call *done)
598{
599	int rc = -ENOMEM;
600	unsigned int xid;
601	const char *full_path;
602	void *page;
603	char *target_path = NULL;
604	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
605	struct tcon_link *tlink = NULL;
606	struct cifs_tcon *tcon;
607	struct TCP_Server_Info *server;
608
609	if (!direntry)
610		return ERR_PTR(-ECHILD);
611
612	xid = get_xid();
613
614	tlink = cifs_sb_tlink(cifs_sb);
615	if (IS_ERR(tlink)) {
616		free_xid(xid);
617		return ERR_CAST(tlink);
618	}
619	tcon = tlink_tcon(tlink);
620	server = tcon->ses->server;
621
622	page = alloc_dentry_path();
623	full_path = build_path_from_dentry(direntry, page);
624	if (IS_ERR(full_path)) {
625		free_xid(xid);
626		cifs_put_tlink(tlink);
627		free_dentry_path(page);
628		return ERR_CAST(full_path);
629	}
630
631	cifs_dbg(FYI, "Full path: %s inode = 0x%p\n", full_path, inode);
632
633	rc = -EACCES;
634	/*
635	 * First try Minshall+French Symlinks, if configured
636	 * and fallback to UNIX Extensions Symlinks.
637	 */
638	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
639		rc = query_mf_symlink(xid, tcon, cifs_sb, full_path,
640				      &target_path);
641
642	if (rc != 0 && server->ops->query_symlink) {
643		struct cifsInodeInfo *cifsi = CIFS_I(inode);
644		bool reparse_point = false;
645
646		if (cifsi->cifsAttrs & ATTR_REPARSE)
647			reparse_point = true;
648
649		rc = server->ops->query_symlink(xid, tcon, cifs_sb, full_path,
650						&target_path, reparse_point);
651	}
652
653	free_dentry_path(page);
654	free_xid(xid);
655	cifs_put_tlink(tlink);
656	if (rc != 0) {
657		kfree(target_path);
658		return ERR_PTR(rc);
659	}
660	set_delayed_call(done, kfree_link, target_path);
661	return target_path;
662}
663
664int
665cifs_symlink(struct user_namespace *mnt_userns, struct inode *inode,
666	     struct dentry *direntry, const char *symname)
667{
668	int rc = -EOPNOTSUPP;
669	unsigned int xid;
670	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
671	struct tcon_link *tlink;
672	struct cifs_tcon *pTcon;
673	const char *full_path;
674	void *page;
675	struct inode *newinode = NULL;
676
677	if (unlikely(cifs_forced_shutdown(cifs_sb)))
678		return -EIO;
679
680	page = alloc_dentry_path();
681	if (!page)
682		return -ENOMEM;
683
684	xid = get_xid();
685
686	tlink = cifs_sb_tlink(cifs_sb);
687	if (IS_ERR(tlink)) {
688		rc = PTR_ERR(tlink);
689		goto symlink_exit;
690	}
691	pTcon = tlink_tcon(tlink);
692
693	full_path = build_path_from_dentry(direntry, page);
694	if (IS_ERR(full_path)) {
695		rc = PTR_ERR(full_path);
696		goto symlink_exit;
697	}
698
699	cifs_dbg(FYI, "Full path: %s\n", full_path);
700	cifs_dbg(FYI, "symname is %s\n", symname);
701
702	/* BB what if DFS and this volume is on different share? BB */
703	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
704		rc = create_mf_symlink(xid, pTcon, cifs_sb, full_path, symname);
 
705	else if (pTcon->unix_ext)
706		rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname,
707					   cifs_sb->local_nls,
708					   cifs_remap(cifs_sb));
 
709	/* else
710	   rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName,
711					cifs_sb_target->local_nls); */
712
713	if (rc == 0) {
714		if (pTcon->posix_extensions)
715			rc = smb311_posix_get_inode_info(&newinode, full_path, inode->i_sb, xid);
716		else if (pTcon->unix_ext)
717			rc = cifs_get_inode_info_unix(&newinode, full_path,
718						      inode->i_sb, xid);
719		else
720			rc = cifs_get_inode_info(&newinode, full_path, NULL,
721						 inode->i_sb, xid, NULL);
722
723		if (rc != 0) {
724			cifs_dbg(FYI, "Create symlink ok, getinodeinfo fail rc = %d\n",
725				 rc);
726		} else {
727			d_instantiate(direntry, newinode);
728		}
729	}
730symlink_exit:
731	free_dentry_path(page);
732	cifs_put_tlink(tlink);
733	free_xid(xid);
734	return rc;
735}