[linux.git] / fs / cifs / link.c

/*
 *   fs/cifs/link.c
 *
 *   Copyright (C) International Business Machines  Corp., 2002,2008
 *   Author(s): Steve French ([email protected])
 *
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as published
 *   by the Free Software Foundation; either version 2.1 of the License, or
 *   (at your option) any later version.
 *
 *   This library is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
 *   the GNU Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public License
 *   along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
#include <linux/fs.h>
#include <linux/stat.h>
#include <linux/slab.h>
#include <linux/namei.h>
#include "cifsfs.h"
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"

#define CIFS_MF_SYMLINK_LEN_OFFSET (4+1)
#define CIFS_MF_SYMLINK_MD5_OFFSET (CIFS_MF_SYMLINK_LEN_OFFSET+(4+1))
#define CIFS_MF_SYMLINK_LINK_OFFSET (CIFS_MF_SYMLINK_MD5_OFFSET+(32+1))
#define CIFS_MF_SYMLINK_LINK_MAXLEN (1024)
#define CIFS_MF_SYMLINK_FILE_SIZE \
	(CIFS_MF_SYMLINK_LINK_OFFSET + CIFS_MF_SYMLINK_LINK_MAXLEN)

#define CIFS_MF_SYMLINK_LEN_FORMAT "XSym\n%04u\n"
#define CIFS_MF_SYMLINK_MD5_FORMAT \
	"%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n"
#define CIFS_MF_SYMLINK_MD5_ARGS(md5_hash) \
	md5_hash[0],  md5_hash[1],  md5_hash[2],  md5_hash[3], \
	md5_hash[4],  md5_hash[5],  md5_hash[6],  md5_hash[7], \
	md5_hash[8],  md5_hash[9],  md5_hash[10], md5_hash[11],\
	md5_hash[12], md5_hash[13], md5_hash[14], md5_hash[15]

static int
symlink_hash(unsigned int link_len, const char *link_str, u8 *md5_hash)
{
	int rc;
	unsigned int size;
	struct crypto_shash *md5;
	struct sdesc *sdescmd5;

	md5 = crypto_alloc_shash("md5", 0, 0);
	if (IS_ERR(md5)) {
		rc = PTR_ERR(md5);
		cERROR(1, "%s: Crypto md5 allocation error %d", __func__, rc);
		return rc;
	}
	size = sizeof(struct shash_desc) + crypto_shash_descsize(md5);
	sdescmd5 = kmalloc(size, GFP_KERNEL);
	if (!sdescmd5) {
		rc = -ENOMEM;
		cERROR(1, "%s: Memory allocation failure", __func__);
		goto symlink_hash_err;
	}
	sdescmd5->shash.tfm = md5;
	sdescmd5->shash.flags = 0x0;

	rc = crypto_shash_init(&sdescmd5->shash);
	if (rc) {
		cERROR(1, "%s: Could not init md5 shash", __func__);
		goto symlink_hash_err;
	}
	rc = crypto_shash_update(&sdescmd5->shash, link_str, link_len);
	if (rc) {
		cERROR(1, "%s: Could not update iwth link_str", __func__);
		goto symlink_hash_err;
	}
	rc = crypto_shash_final(&sdescmd5->shash, md5_hash);
	if (rc)
		cERROR(1, "%s: Could not generate md5 hash", __func__);

symlink_hash_err:
	crypto_free_shash(md5);
	kfree(sdescmd5);

	return rc;
}

static int
CIFSParseMFSymlink(const u8 *buf,
		   unsigned int buf_len,
		   unsigned int *_link_len,
		   char **_link_str)
{
	int rc;
	unsigned int link_len;
	const char *md5_str1;
	const char *link_str;
	u8 md5_hash[16];
	char md5_str2[34];

	if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
		return -EINVAL;

	md5_str1 = (const char *)&buf[CIFS_MF_SYMLINK_MD5_OFFSET];
	link_str = (const char *)&buf[CIFS_MF_SYMLINK_LINK_OFFSET];

	rc = sscanf(buf, CIFS_MF_SYMLINK_LEN_FORMAT, &link_len);
	if (rc != 1)
		return -EINVAL;

	rc = symlink_hash(link_len, link_str, md5_hash);
	if (rc) {
		cFYI(1, "%s: MD5 hash failure: %d", __func__, rc);
		return rc;
	}

	snprintf(md5_str2, sizeof(md5_str2),
		 CIFS_MF_SYMLINK_MD5_FORMAT,
		 CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));

	if (strncmp(md5_str1, md5_str2, 17) != 0)
		return -EINVAL;

	if (_link_str) {
		*_link_str = kstrndup(link_str, link_len, GFP_KERNEL);
		if (!*_link_str)
			return -ENOMEM;
	}

	*_link_len = link_len;
	return 0;
}

static int
CIFSFormatMFSymlink(u8 *buf, unsigned int buf_len, const char *link_str)
{
	int rc;
	unsigned int link_len;
	unsigned int ofs;
	u8 md5_hash[16];

	if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
		return -EINVAL;

	link_len = strlen(link_str);

	if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
		return -ENAMETOOLONG;

	rc = symlink_hash(link_len, link_str, md5_hash);
	if (rc) {
		cFYI(1, "%s: MD5 hash failure: %d", __func__, rc);
		return rc;
	}

	snprintf(buf, buf_len,
		 CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT,
		 link_len,
		 CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));

	ofs = CIFS_MF_SYMLINK_LINK_OFFSET;
	memcpy(buf + ofs, link_str, link_len);

	ofs += link_len;
	if (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
		buf[ofs] = '\n';
		ofs++;
	}

	while (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
		buf[ofs] = ' ';
		ofs++;
	}

	return 0;
}

static int
CIFSCreateMFSymLink(const unsigned int xid, struct cifs_tcon *tcon,
		    const char *fromName, const char *toName,
		    struct cifs_sb_info *cifs_sb)
{
	int rc;
	int oplock = 0;
	int remap;
	int create_options = CREATE_NOT_DIR;
	__u16 netfid = 0;
	u8 *buf;
	unsigned int bytes_written = 0;
	struct cifs_io_parms io_parms;
	struct nls_table *nls_codepage;

	nls_codepage = cifs_sb->local_nls;
	remap = cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR;

	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
	if (!buf)
		return -ENOMEM;

	rc = CIFSFormatMFSymlink(buf, CIFS_MF_SYMLINK_FILE_SIZE, toName);
	if (rc != 0) {
		kfree(buf);
		return rc;
	}

	if (backup_cred(cifs_sb))
		create_options |= CREATE_OPEN_BACKUP_INTENT;

	rc = CIFSSMBOpen(xid, tcon, fromName, FILE_CREATE, GENERIC_WRITE,
			 create_options, &netfid, &oplock, NULL,
			 nls_codepage, remap);
	if (rc != 0) {
		kfree(buf);
		return rc;
	}

	io_parms.netfid = netfid;
	io_parms.pid = current->tgid;
	io_parms.tcon = tcon;
	io_parms.offset = 0;
	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;

	rc = CIFSSMBWrite(xid, &io_parms, &bytes_written, buf, NULL, 0);
	CIFSSMBClose(xid, tcon, netfid);
	kfree(buf);
	if (rc != 0)
		return rc;

	if (bytes_written != CIFS_MF_SYMLINK_FILE_SIZE)
		return -EIO;

	return 0;
}

static int
CIFSQueryMFSymLink(const unsigned int xid, struct cifs_tcon *tcon,
		   const unsigned char *searchName, char **symlinkinfo,
		   const struct nls_table *nls_codepage, int remap)
{
	int rc;
	int oplock = 0;
	__u16 netfid = 0;
	u8 *buf;
	char *pbuf;
	unsigned int bytes_read = 0;
	int buf_type = CIFS_NO_BUFFER;
	unsigned int link_len = 0;
	struct cifs_io_parms io_parms;
	FILE_ALL_INFO file_info;

	rc = CIFSSMBOpen(xid, tcon, searchName, FILE_OPEN, GENERIC_READ,
			 CREATE_NOT_DIR, &netfid, &oplock, &file_info,
			 nls_codepage, remap);
	if (rc != 0)
		return rc;

	if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
		CIFSSMBClose(xid, tcon, netfid);
		/* it's not a symlink */
		return -EINVAL;
	}

	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
	if (!buf)
		return -ENOMEM;
	pbuf = buf;
	io_parms.netfid = netfid;
	io_parms.pid = current->tgid;
	io_parms.tcon = tcon;
	io_parms.offset = 0;
	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;

	rc = CIFSSMBRead(xid, &io_parms, &bytes_read, &pbuf, &buf_type);
	CIFSSMBClose(xid, tcon, netfid);
	if (rc != 0) {
		kfree(buf);
		return rc;
	}

	rc = CIFSParseMFSymlink(buf, bytes_read, &link_len, symlinkinfo);
	kfree(buf);
	if (rc != 0)
		return rc;

	return 0;
}

bool
CIFSCouldBeMFSymlink(const struct cifs_fattr *fattr)
{
	if (!(fattr->cf_mode & S_IFREG))
		/* it's not a symlink */
		return false;

	if (fattr->cf_eof != CIFS_MF_SYMLINK_FILE_SIZE)
		/* it's not a symlink */
		return false;

	return true;
}

int
CIFSCheckMFSymlink(struct cifs_fattr *fattr,
		   const unsigned char *path,
		   struct cifs_sb_info *cifs_sb, unsigned int xid)
{
	int rc;
	int oplock = 0;
	__u16 netfid = 0;
	struct tcon_link *tlink;
	struct cifs_tcon *pTcon;
	struct cifs_io_parms io_parms;
	u8 *buf;
	char *pbuf;
	unsigned int bytes_read = 0;
	int buf_type = CIFS_NO_BUFFER;
	unsigned int link_len = 0;
	FILE_ALL_INFO file_info;

	if (!CIFSCouldBeMFSymlink(fattr))
		/* it's not a symlink */
		return 0;

	tlink = cifs_sb_tlink(cifs_sb);
	if (IS_ERR(tlink))
		return PTR_ERR(tlink);
	pTcon = tlink_tcon(tlink);

	rc = CIFSSMBOpen(xid, pTcon, path, FILE_OPEN, GENERIC_READ,
			 CREATE_NOT_DIR, &netfid, &oplock, &file_info,
			 cifs_sb->local_nls,
			 cifs_sb->mnt_cifs_flags &
				CIFS_MOUNT_MAP_SPECIAL_CHR);
	if (rc != 0)
		goto out;

	if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
		CIFSSMBClose(xid, pTcon, netfid);
		/* it's not a symlink */
		goto out;
	}

	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
	if (!buf) {
		rc = -ENOMEM;
		goto out;
	}
	pbuf = buf;
	io_parms.netfid = netfid;
	io_parms.pid = current->tgid;
	io_parms.tcon = pTcon;
	io_parms.offset = 0;
	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;

	rc = CIFSSMBRead(xid, &io_parms, &bytes_read, &pbuf, &buf_type);
	CIFSSMBClose(xid, pTcon, netfid);
	if (rc != 0) {
		kfree(buf);
		goto out;
	}

	rc = CIFSParseMFSymlink(buf, bytes_read, &link_len, NULL);
	kfree(buf);
	if (rc == -EINVAL) {
		/* it's not a symlink */
		rc = 0;
		goto out;
	}

	if (rc != 0)
		goto out;

	/* it is a symlink */
	fattr->cf_eof = link_len;
	fattr->cf_mode &= ~S_IFMT;
	fattr->cf_mode |= S_IFLNK | S_IRWXU | S_IRWXG | S_IRWXO;
	fattr->cf_dtype = DT_LNK;
out:
	cifs_put_tlink(tlink);
	return rc;
}

int
cifs_hardlink(struct dentry *old_file, struct inode *inode,
	      struct dentry *direntry)
{
	int rc = -EACCES;
	unsigned int xid;
	char *from_name = NULL;
	char *to_name = NULL;
	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
	struct tcon_link *tlink;
	struct cifs_tcon *tcon;
	struct TCP_Server_Info *server;
	struct cifsInodeInfo *cifsInode;

	tlink = cifs_sb_tlink(cifs_sb);
	if (IS_ERR(tlink))
		return PTR_ERR(tlink);
	tcon = tlink_tcon(tlink);

	xid = get_xid();

	from_name = build_path_from_dentry(old_file);
	to_name = build_path_from_dentry(direntry);
	if ((from_name == NULL) || (to_name == NULL)) {
		rc = -ENOMEM;
		goto cifs_hl_exit;
	}

	if (tcon->unix_ext)
		rc = CIFSUnixCreateHardLink(xid, tcon, from_name, to_name,
					    cifs_sb->local_nls,
					    cifs_sb->mnt_cifs_flags &
						CIFS_MOUNT_MAP_SPECIAL_CHR);
	else {
		server = tcon->ses->server;
		if (!server->ops->create_hardlink)
			return -ENOSYS;
		rc = server->ops->create_hardlink(xid, tcon, from_name, to_name,
						  cifs_sb);
		if ((rc == -EIO) || (rc == -EINVAL))
			rc = -EOPNOTSUPP;
	}

	d_drop(direntry);	/* force new lookup from server of target */

	/*
	 * if source file is cached (oplocked) revalidate will not go to server
	 * until the file is closed or oplock broken so update nlinks locally
	 */
	if (old_file->d_inode) {
		cifsInode = CIFS_I(old_file->d_inode);
		if (rc == 0) {
			spin_lock(&old_file->d_inode->i_lock);
			inc_nlink(old_file->d_inode);
			spin_unlock(&old_file->d_inode->i_lock);
			/*
			 * BB should we make this contingent on superblock flag
			 * NOATIME?
			 */
			/* old_file->d_inode->i_ctime = CURRENT_TIME; */
			/*
			 * parent dir timestamps will update from srv within a
			 * second, would it really be worth it to set the parent
			 * dir cifs inode time to zero to force revalidate
			 * (faster) for it too?
			 */
		}
		/*
		 * if not oplocked will force revalidate to get info on source
		 * file from srv
		 */
		cifsInode->time = 0;

		/*
		 * Will update parent dir timestamps from srv within a second.
		 * Would it really be worth it to set the parent dir (cifs
		 * inode) time field to zero to force revalidate on parent
		 * directory faster ie
		 *
		 * CIFS_I(inode)->time = 0;
		 */
	}

cifs_hl_exit:
	kfree(from_name);
	kfree(to_name);
	free_xid(xid);
	cifs_put_tlink(tlink);
	return rc;
}

void *
cifs_follow_link(struct dentry *direntry, struct nameidata *nd)
{
	struct inode *inode = direntry->d_inode;
	int rc = -ENOMEM;
	unsigned int xid;
	char *full_path = NULL;
	char *target_path = NULL;
	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
	struct tcon_link *tlink = NULL;
	struct cifs_tcon *tcon;

	xid = get_xid();

	tlink = cifs_sb_tlink(cifs_sb);
	if (IS_ERR(tlink)) {
		rc = PTR_ERR(tlink);
		tlink = NULL;
		goto out;
	}
	tcon = tlink_tcon(tlink);

	/*
	 * For now, we just handle symlinks with unix extensions enabled.
	 * Eventually we should handle NTFS reparse points, and MacOS
	 * symlink support. For instance...
	 *
	 * rc = CIFSSMBQueryReparseLinkInfo(...)
	 *
	 * For now, just return -EACCES when the server doesn't support posix
	 * extensions. Note that we still allow querying symlinks when posix
	 * extensions are manually disabled. We could disable these as well
	 * but there doesn't seem to be any harm in allowing the client to
	 * read them.
	 */
	if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&
	    !cap_unix(tcon->ses)) {
		rc = -EACCES;
		goto out;
	}

	full_path = build_path_from_dentry(direntry);
	if (!full_path)
		goto out;

	cFYI(1, "Full path: %s inode = 0x%p", full_path, inode);

	rc = -EACCES;
	/*
	 * First try Minshall+French Symlinks, if configured
	 * and fallback to UNIX Extensions Symlinks.
	 */
	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
		rc = CIFSQueryMFSymLink(xid, tcon, full_path, &target_path,
					cifs_sb->local_nls,
					cifs_sb->mnt_cifs_flags &
						CIFS_MOUNT_MAP_SPECIAL_CHR);

	if ((rc != 0) && cap_unix(tcon->ses))
		rc = CIFSSMBUnixQuerySymLink(xid, tcon, full_path, &target_path,
					     cifs_sb->local_nls);

	kfree(full_path);
out:
	if (rc != 0) {
		kfree(target_path);
		target_path = ERR_PTR(rc);
	}

	free_xid(xid);
	if (tlink)
		cifs_put_tlink(tlink);
	nd_set_link(nd, target_path);
	return NULL;
}

int
cifs_symlink(struct inode *inode, struct dentry *direntry, const char *symname)
{
	int rc = -EOPNOTSUPP;
	unsigned int xid;
	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
	struct tcon_link *tlink;
	struct cifs_tcon *pTcon;
	char *full_path = NULL;
	struct inode *newinode = NULL;

	xid = get_xid();

	tlink = cifs_sb_tlink(cifs_sb);
	if (IS_ERR(tlink)) {
		rc = PTR_ERR(tlink);
		goto symlink_exit;
	}
	pTcon = tlink_tcon(tlink);

	full_path = build_path_from_dentry(direntry);
	if (full_path == NULL) {
		rc = -ENOMEM;
		goto symlink_exit;
	}

	cFYI(1, "Full path: %s", full_path);
	cFYI(1, "symname is %s", symname);

	/* BB what if DFS and this volume is on different share? BB */
	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
		rc = CIFSCreateMFSymLink(xid, pTcon, full_path, symname,
					cifs_sb);
	else if (pTcon->unix_ext)
		rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname,
					   cifs_sb->local_nls);
	/* else
	   rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName,
					cifs_sb_target->local_nls); */

	if (rc == 0) {
		if (pTcon->unix_ext)
			rc = cifs_get_inode_info_unix(&newinode, full_path,
						      inode->i_sb, xid);
		else
			rc = cifs_get_inode_info(&newinode, full_path, NULL,
						 inode->i_sb, xid, NULL);

		if (rc != 0) {
			cFYI(1, "Create symlink ok, getinodeinfo fail rc = %d",
			      rc);
		} else {
			d_instantiate(direntry, newinode);
		}
	}
symlink_exit:
	kfree(full_path);
	cifs_put_tlink(tlink);
	free_xid(xid);
	return rc;
}

void cifs_put_link(struct dentry *direntry, struct nameidata *nd, void *cookie)
{
	char *p = nd_get_link(nd);
	if (!IS_ERR(p))
		kfree(p);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* fs/cifs/link.c
	3	*
366781c1	4	* Copyright (C) International Business Machines Corp., 2002,2008
1da177e4 LT	5	* Author(s): Steve French ([email protected])
	6	*
	7	* This library is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU Lesser General Public License as published
	9	* by the Free Software Foundation; either version 2.1 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This library is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
	15	* the GNU Lesser General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU Lesser General Public License
	18	* along with this library; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	20	*/
	21	#include <linux/fs.h>
	22	#include <linux/stat.h>
5a0e3ad6	23	#include <linux/slab.h>
1da177e4 LT	24	#include <linux/namei.h>
	25	#include "cifsfs.h"
	26	#include "cifspdu.h"
	27	#include "cifsglob.h"
	28	#include "cifsproto.h"
	29	#include "cifs_debug.h"
	30	#include "cifs_fs_sb.h"
c69c1b6e SM	31
	32	#define CIFS_MF_SYMLINK_LEN_OFFSET (4+1)
	33	#define CIFS_MF_SYMLINK_MD5_OFFSET (CIFS_MF_SYMLINK_LEN_OFFSET+(4+1))
	34	#define CIFS_MF_SYMLINK_LINK_OFFSET (CIFS_MF_SYMLINK_MD5_OFFSET+(32+1))
	35	#define CIFS_MF_SYMLINK_LINK_MAXLEN (1024)
	36	#define CIFS_MF_SYMLINK_FILE_SIZE \
	37	(CIFS_MF_SYMLINK_LINK_OFFSET + CIFS_MF_SYMLINK_LINK_MAXLEN)
	38
	39	#define CIFS_MF_SYMLINK_LEN_FORMAT "XSym\n%04u\n"
	40	#define CIFS_MF_SYMLINK_MD5_FORMAT \
	41	"%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n"
	42	#define CIFS_MF_SYMLINK_MD5_ARGS(md5_hash) \
	43	md5_hash[0], md5_hash[1], md5_hash[2], md5_hash[3], \
	44	md5_hash[4], md5_hash[5], md5_hash[6], md5_hash[7], \
	45	md5_hash[8], md5_hash[9], md5_hash[10], md5_hash[11],\
	46	md5_hash[12], md5_hash[13], md5_hash[14], md5_hash[15]
	47
93c100c0 SF	48	static int
	49	symlink_hash(unsigned int link_len, const char link_str, u8 md5_hash)
	50	{
	51	int rc;
	52	unsigned int size;
	53	struct crypto_shash *md5;
	54	struct sdesc *sdescmd5;
	55
	56	md5 = crypto_alloc_shash("md5", 0, 0);
ee2c9258	57	if (IS_ERR(md5)) {
ffeb414a	58	rc = PTR_ERR(md5);
ac3aa2f8	59	cERROR(1, "%s: Crypto md5 allocation error %d", __func__, rc);
ffeb414a	60	return rc;
93c100c0 SF	61	}
	62	size = sizeof(struct shash_desc) + crypto_shash_descsize(md5);
	63	sdescmd5 = kmalloc(size, GFP_KERNEL);
	64	if (!sdescmd5) {
	65	rc = -ENOMEM;
ac3aa2f8	66	cERROR(1, "%s: Memory allocation failure", __func__);
93c100c0 SF	67	goto symlink_hash_err;
	68	}
	69	sdescmd5->shash.tfm = md5;
	70	sdescmd5->shash.flags = 0x0;
	71
	72	rc = crypto_shash_init(&sdescmd5->shash);
	73	if (rc) {
ac3aa2f8	74	cERROR(1, "%s: Could not init md5 shash", __func__);
93c100c0 SF	75	goto symlink_hash_err;
93c100c0 SF	76	}
14cae324 SP	77	rc = crypto_shash_update(&sdescmd5->shash, link_str, link_len);
14cae324 SP	78	if (rc) {
ac3aa2f8	79	cERROR(1, "%s: Could not update iwth link_str", __func__);
14cae324 SP	80	goto symlink_hash_err;
14cae324 SP	81	}
93c100c0	82	rc = crypto_shash_final(&sdescmd5->shash, md5_hash);
14cae324	83	if (rc)
ac3aa2f8	84	cERROR(1, "%s: Could not generate md5 hash", __func__);
93c100c0 SF	85
	86	symlink_hash_err:
	87	crypto_free_shash(md5);
	88	kfree(sdescmd5);
	89
	90	return rc;
	91	}
	92
c69c1b6e SM	93	static int
	94	CIFSParseMFSymlink(const u8 *buf,
	95	unsigned int buf_len,
	96	unsigned int *_link_len,
	97	char **_link_str)
	98	{
	99	int rc;
	100	unsigned int link_len;
	101	const char *md5_str1;
	102	const char *link_str;
c69c1b6e SM	103	u8 md5_hash[16];
	104	char md5_str2[34];
	105
	106	if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
	107	return -EINVAL;
	108
	109	md5_str1 = (const char *)&buf[CIFS_MF_SYMLINK_MD5_OFFSET];
	110	link_str = (const char *)&buf[CIFS_MF_SYMLINK_LINK_OFFSET];
	111
	112	rc = sscanf(buf, CIFS_MF_SYMLINK_LEN_FORMAT, &link_len);
	113	if (rc != 1)
	114	return -EINVAL;
	115
93c100c0 SF	116	rc = symlink_hash(link_len, link_str, md5_hash);
93c100c0 SF	117	if (rc) {
ac3aa2f8	118	cFYI(1, "%s: MD5 hash failure: %d", __func__, rc);
93c100c0 SF	119	return rc;
93c100c0 SF	120	}
c69c1b6e SM	121
	122	snprintf(md5_str2, sizeof(md5_str2),
	123	CIFS_MF_SYMLINK_MD5_FORMAT,
	124	CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
	125
	126	if (strncmp(md5_str1, md5_str2, 17) != 0)
	127	return -EINVAL;
	128
	129	if (_link_str) {
	130	*_link_str = kstrndup(link_str, link_len, GFP_KERNEL);
	131	if (!*_link_str)
	132	return -ENOMEM;
	133	}
	134
	135	*_link_len = link_len;
	136	return 0;
	137	}
1da177e4	138
0fd43ae4	139	static int
18bddd10 SM	140	CIFSFormatMFSymlink(u8 buf, unsigned int buf_len, const char link_str)
18bddd10 SM	141	{
93c100c0	142	int rc;
18bddd10 SM	143	unsigned int link_len;
18bddd10 SM	144	unsigned int ofs;
18bddd10 SM	145	u8 md5_hash[16];
	146
	147	if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
	148	return -EINVAL;
	149
	150	link_len = strlen(link_str);
	151
	152	if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
	153	return -ENAMETOOLONG;
	154
93c100c0 SF	155	rc = symlink_hash(link_len, link_str, md5_hash);
93c100c0 SF	156	if (rc) {
ac3aa2f8	157	cFYI(1, "%s: MD5 hash failure: %d", __func__, rc);
93c100c0 SF	158	return rc;
93c100c0 SF	159	}
18bddd10 SM	160
	161	snprintf(buf, buf_len,
	162	CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT,
	163	link_len,
	164	CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
	165
	166	ofs = CIFS_MF_SYMLINK_LINK_OFFSET;
	167	memcpy(buf + ofs, link_str, link_len);
	168
	169	ofs += link_len;
	170	if (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
	171	buf[ofs] = '\n';
	172	ofs++;
	173	}
	174
	175	while (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
	176	buf[ofs] = ' ';
	177	ofs++;
	178	}
	179
	180	return 0;
	181	}
	182
8713d01d	183	static int
6d5786a3	184	CIFSCreateMFSymLink(const unsigned int xid, struct cifs_tcon *tcon,
8713d01d	185	const char fromName, const char toName,
3d3ea8e6	186	struct cifs_sb_info *cifs_sb)
8713d01d SM	187	{
	188	int rc;
	189	int oplock = 0;
3d3ea8e6 SP	190	int remap;
3d3ea8e6 SP	191	int create_options = CREATE_NOT_DIR;
8713d01d SM	192	__u16 netfid = 0;
	193	u8 *buf;
	194	unsigned int bytes_written = 0;
fa2989f4	195	struct cifs_io_parms io_parms;
3d3ea8e6 SP	196	struct nls_table *nls_codepage;
	197
	198	nls_codepage = cifs_sb->local_nls;
	199	remap = cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR;
8713d01d SM	200
	201	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
	202	if (!buf)
	203	return -ENOMEM;
	204
	205	rc = CIFSFormatMFSymlink(buf, CIFS_MF_SYMLINK_FILE_SIZE, toName);
	206	if (rc != 0) {
	207	kfree(buf);
	208	return rc;
	209	}
	210
3d3ea8e6 SP	211	if (backup_cred(cifs_sb))
	212	create_options \|= CREATE_OPEN_BACKUP_INTENT;
	213
8713d01d	214	rc = CIFSSMBOpen(xid, tcon, fromName, FILE_CREATE, GENERIC_WRITE,
3d3ea8e6	215	create_options, &netfid, &oplock, NULL,
8713d01d SM	216	nls_codepage, remap);
	217	if (rc != 0) {
	218	kfree(buf);
	219	return rc;
	220	}
	221
fa2989f4 PS	222	io_parms.netfid = netfid;
	223	io_parms.pid = current->tgid;
	224	io_parms.tcon = tcon;
	225	io_parms.offset = 0;
	226	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
	227
	228	rc = CIFSSMBWrite(xid, &io_parms, &bytes_written, buf, NULL, 0);
8713d01d SM	229	CIFSSMBClose(xid, tcon, netfid);
	230	kfree(buf);
	231	if (rc != 0)
	232	return rc;
	233
	234	if (bytes_written != CIFS_MF_SYMLINK_FILE_SIZE)
	235	return -EIO;
	236
	237	return 0;
	238	}
	239
	240	static int
6d5786a3	241	CIFSQueryMFSymLink(const unsigned int xid, struct cifs_tcon *tcon,
0fd43ae4 SM	242	const unsigned char searchName, char *symlinkinfo,
	243	const struct nls_table *nls_codepage, int remap)
	244	{
	245	int rc;
	246	int oplock = 0;
	247	__u16 netfid = 0;
	248	u8 *buf;
	249	char *pbuf;
	250	unsigned int bytes_read = 0;
	251	int buf_type = CIFS_NO_BUFFER;
	252	unsigned int link_len = 0;
d4ffff1f	253	struct cifs_io_parms io_parms;
0fd43ae4 SM	254	FILE_ALL_INFO file_info;
	255
	256	rc = CIFSSMBOpen(xid, tcon, searchName, FILE_OPEN, GENERIC_READ,
	257	CREATE_NOT_DIR, &netfid, &oplock, &file_info,
	258	nls_codepage, remap);
	259	if (rc != 0)
	260	return rc;
	261
5443d130	262	if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
0fd43ae4 SM	263	CIFSSMBClose(xid, tcon, netfid);
	264	/* it's not a symlink */
	265	return -EINVAL;
	266	}
	267
	268	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
	269	if (!buf)
	270	return -ENOMEM;
	271	pbuf = buf;
d4ffff1f PS	272	io_parms.netfid = netfid;
	273	io_parms.pid = current->tgid;
	274	io_parms.tcon = tcon;
	275	io_parms.offset = 0;
	276	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
0fd43ae4	277
d4ffff1f	278	rc = CIFSSMBRead(xid, &io_parms, &bytes_read, &pbuf, &buf_type);
0fd43ae4 SM	279	CIFSSMBClose(xid, tcon, netfid);
	280	if (rc != 0) {
	281	kfree(buf);
	282	return rc;
	283	}
	284
	285	rc = CIFSParseMFSymlink(buf, bytes_read, &link_len, symlinkinfo);
	286	kfree(buf);
	287	if (rc != 0)
	288	return rc;
	289
	290	return 0;
	291	}
	292
8bfb50a8 SM	293	bool
	294	CIFSCouldBeMFSymlink(const struct cifs_fattr *fattr)
	295	{
	296	if (!(fattr->cf_mode & S_IFREG))
	297	/* it's not a symlink */
	298	return false;
	299
	300	if (fattr->cf_eof != CIFS_MF_SYMLINK_FILE_SIZE)
	301	/* it's not a symlink */
	302	return false;
	303
	304	return true;
	305	}
	306
	307	int
	308	CIFSCheckMFSymlink(struct cifs_fattr *fattr,
	309	const unsigned char *path,
6d5786a3	310	struct cifs_sb_info *cifs_sb, unsigned int xid)
8bfb50a8 SM	311	{
	312	int rc;
	313	int oplock = 0;
	314	__u16 netfid = 0;
7ffec372	315	struct tcon_link *tlink;
96daf2b0	316	struct cifs_tcon *pTcon;
d4ffff1f	317	struct cifs_io_parms io_parms;
8bfb50a8 SM	318	u8 *buf;
	319	char *pbuf;
	320	unsigned int bytes_read = 0;
	321	int buf_type = CIFS_NO_BUFFER;
	322	unsigned int link_len = 0;
	323	FILE_ALL_INFO file_info;
	324
	325	if (!CIFSCouldBeMFSymlink(fattr))
	326	/* it's not a symlink */
	327	return 0;
	328
7ffec372 JL	329	tlink = cifs_sb_tlink(cifs_sb);
	330	if (IS_ERR(tlink))
	331	return PTR_ERR(tlink);
	332	pTcon = tlink_tcon(tlink);
	333
8bfb50a8 SM	334	rc = CIFSSMBOpen(xid, pTcon, path, FILE_OPEN, GENERIC_READ,
	335	CREATE_NOT_DIR, &netfid, &oplock, &file_info,
	336	cifs_sb->local_nls,
	337	cifs_sb->mnt_cifs_flags &
	338	CIFS_MOUNT_MAP_SPECIAL_CHR);
	339	if (rc != 0)
7ffec372	340	goto out;
8bfb50a8	341
5443d130	342	if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
8bfb50a8 SM	343	CIFSSMBClose(xid, pTcon, netfid);
8bfb50a8 SM	344	/* it's not a symlink */
7ffec372	345	goto out;
8bfb50a8 SM	346	}
	347
	348	buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
7ffec372 JL	349	if (!buf) {
	350	rc = -ENOMEM;
	351	goto out;
	352	}
8bfb50a8	353	pbuf = buf;
d4ffff1f PS	354	io_parms.netfid = netfid;
	355	io_parms.pid = current->tgid;
	356	io_parms.tcon = pTcon;
	357	io_parms.offset = 0;
	358	io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
8bfb50a8	359
d4ffff1f	360	rc = CIFSSMBRead(xid, &io_parms, &bytes_read, &pbuf, &buf_type);
8bfb50a8 SM	361	CIFSSMBClose(xid, pTcon, netfid);
	362	if (rc != 0) {
	363	kfree(buf);
7ffec372	364	goto out;
8bfb50a8 SM	365	}
	366
	367	rc = CIFSParseMFSymlink(buf, bytes_read, &link_len, NULL);
	368	kfree(buf);
7ffec372	369	if (rc == -EINVAL) {
8bfb50a8	370	/* it's not a symlink */
7ffec372 JL	371	rc = 0;
	372	goto out;
	373	}
	374
8bfb50a8	375	if (rc != 0)
7ffec372	376	goto out;
8bfb50a8 SM	377
	378	/* it is a symlink */
	379	fattr->cf_eof = link_len;
	380	fattr->cf_mode &= ~S_IFMT;
	381	fattr->cf_mode \|= S_IFLNK \| S_IRWXU \| S_IRWXG \| S_IRWXO;
	382	fattr->cf_dtype = DT_LNK;
7ffec372 JL	383	out:
	384	cifs_put_tlink(tlink);
	385	return rc;
8bfb50a8 SM	386	}
8bfb50a8 SM	387
1da177e4 LT	388	int
	389	cifs_hardlink(struct dentry old_file, struct inode inode,
	390	struct dentry *direntry)
	391	{
	392	int rc = -EACCES;
6d5786a3	393	unsigned int xid;
d6e906f1 SF	394	char *from_name = NULL;
d6e906f1 SF	395	char *to_name = NULL;
7ffec372 JL	396	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
7ffec372 JL	397	struct tcon_link *tlink;
d6e906f1 SF	398	struct cifs_tcon *tcon;
d6e906f1 SF	399	struct TCP_Server_Info *server;
1da177e4 LT	400	struct cifsInodeInfo *cifsInode;
1da177e4 LT	401
7ffec372 JL	402	tlink = cifs_sb_tlink(cifs_sb);
	403	if (IS_ERR(tlink))
	404	return PTR_ERR(tlink);
d6e906f1	405	tcon = tlink_tcon(tlink);
1da177e4	406
6d5786a3	407	xid = get_xid();
1da177e4	408
d6e906f1 SF	409	from_name = build_path_from_dentry(old_file);
	410	to_name = build_path_from_dentry(direntry);
	411	if ((from_name == NULL) \|\| (to_name == NULL)) {
1da177e4 LT	412	rc = -ENOMEM;
	413	goto cifs_hl_exit;
	414	}
	415
d6e906f1 SF	416	if (tcon->unix_ext)
d6e906f1 SF	417	rc = CIFSUnixCreateHardLink(xid, tcon, from_name, to_name,
7ffec372 JL	418	cifs_sb->local_nls,
7ffec372 JL	419	cifs_sb->mnt_cifs_flags &
737b758c	420	CIFS_MOUNT_MAP_SPECIAL_CHR);
1da177e4	421	else {
d6e906f1 SF	422	server = tcon->ses->server;
	423	if (!server->ops->create_hardlink)
	424	return -ENOSYS;
	425	rc = server->ops->create_hardlink(xid, tcon, from_name, to_name,
	426	cifs_sb);
fb8c4b14 SF	427	if ((rc == -EIO) \|\| (rc == -EINVAL))
fb8c4b14 SF	428	rc = -EOPNOTSUPP;
1da177e4 LT	429	}
1da177e4 LT	430
31ec35d6 SF	431	d_drop(direntry); /* force new lookup from server of target */
31ec35d6 SF	432
d6e906f1 SF	433	/*
	434	* if source file is cached (oplocked) revalidate will not go to server
	435	* until the file is closed or oplock broken so update nlinks locally
	436	*/
fb8c4b14	437	if (old_file->d_inode) {
31ec35d6	438	cifsInode = CIFS_I(old_file->d_inode);
fb8c4b14	439	if (rc == 0) {
b7ca6928	440	spin_lock(&old_file->d_inode->i_lock);
6d6b77f1	441	inc_nlink(old_file->d_inode);
b7ca6928	442	spin_unlock(&old_file->d_inode->i_lock);
d6e906f1 SF	443	/*
	444	* BB should we make this contingent on superblock flag
	445	* NOATIME?
	446	*/
	447	/* old_file->d_inode->i_ctime = CURRENT_TIME; */
	448	/*
	449	* parent dir timestamps will update from srv within a
	450	* second, would it really be worth it to set the parent
	451	* dir cifs inode time to zero to force revalidate
	452	* (faster) for it too?
	453	*/
31ec35d6	454	}
d6e906f1 SF	455	/*
	456	* if not oplocked will force revalidate to get info on source
	457	* file from srv
	458	*/
31ec35d6 SF	459	cifsInode->time = 0;
31ec35d6 SF	460
d6e906f1 SF	461	/*
	462	* Will update parent dir timestamps from srv within a second.
	463	* Would it really be worth it to set the parent dir (cifs
	464	* inode) time field to zero to force revalidate on parent
	465	* directory faster ie
	466	*
	467	* CIFS_I(inode)->time = 0;
	468	*/
1da177e4	469	}
1da177e4 LT	470
1da177e4 LT	471	cifs_hl_exit:
d6e906f1 SF	472	kfree(from_name);
d6e906f1 SF	473	kfree(to_name);
6d5786a3	474	free_xid(xid);
7ffec372	475	cifs_put_tlink(tlink);
1da177e4 LT	476	return rc;
	477	}
	478
cc314eef	479	void *
1da177e4 LT	480	cifs_follow_link(struct dentry direntry, struct nameidata nd)
	481	{
	482	struct inode *inode = direntry->d_inode;
8b6427a2	483	int rc = -ENOMEM;
6d5786a3	484	unsigned int xid;
1da177e4	485	char *full_path = NULL;
8b6427a2 JL	486	char *target_path = NULL;
8b6427a2 JL	487	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
7ffec372	488	struct tcon_link *tlink = NULL;
96daf2b0	489	struct cifs_tcon *tcon;
1da177e4	490
6d5786a3	491	xid = get_xid();
1da177e4	492
7ffec372 JL	493	tlink = cifs_sb_tlink(cifs_sb);
	494	if (IS_ERR(tlink)) {
	495	rc = PTR_ERR(tlink);
	496	tlink = NULL;
	497	goto out;
	498	}
	499	tcon = tlink_tcon(tlink);
	500
8b6427a2 JL	501	/*
	502	* For now, we just handle symlinks with unix extensions enabled.
	503	* Eventually we should handle NTFS reparse points, and MacOS
	504	* symlink support. For instance...
	505	*
	506	* rc = CIFSSMBQueryReparseLinkInfo(...)
	507	*
	508	* For now, just return -EACCES when the server doesn't support posix
	509	* extensions. Note that we still allow querying symlinks when posix
	510	* extensions are manually disabled. We could disable these as well
	511	* but there doesn't seem to be any harm in allowing the client to
	512	* read them.
	513	*/
29e20f9c PS	514	if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS) &&
29e20f9c PS	515	!cap_unix(tcon->ses)) {
8b6427a2 JL	516	rc = -EACCES;
	517	goto out;
	518	}
1da177e4	519
8b6427a2	520	full_path = build_path_from_dentry(direntry);
1da177e4	521	if (!full_path)
460b9696	522	goto out;
1da177e4	523
b6b38f70	524	cFYI(1, "Full path: %s inode = 0x%p", full_path, inode);
1da177e4	525
1b12b9c1 SM	526	rc = -EACCES;
	527	/*
	528	* First try Minshall+French Symlinks, if configured
	529	* and fallback to UNIX Extensions Symlinks.
	530	*/
	531	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
	532	rc = CIFSQueryMFSymLink(xid, tcon, full_path, &target_path,
	533	cifs_sb->local_nls,
	534	cifs_sb->mnt_cifs_flags &
	535	CIFS_MOUNT_MAP_SPECIAL_CHR);
	536
29e20f9c	537	if ((rc != 0) && cap_unix(tcon->ses))
1b12b9c1 SM	538	rc = CIFSSMBUnixQuerySymLink(xid, tcon, full_path, &target_path,
	539	cifs_sb->local_nls);
	540
8b6427a2 JL	541	kfree(full_path);
8b6427a2 JL	542	out:
460b9696	543	if (rc != 0) {
1da177e4 LT	544	kfree(target_path);
	545	target_path = ERR_PTR(rc);
	546	}
	547
6d5786a3	548	free_xid(xid);
7ffec372 JL	549	if (tlink)
7ffec372 JL	550	cifs_put_tlink(tlink);
1da177e4	551	nd_set_link(nd, target_path);
460b9696	552	return NULL;
1da177e4 LT	553	}
	554
	555	int
	556	cifs_symlink(struct inode inode, struct dentry direntry, const char *symname)
	557	{
	558	int rc = -EOPNOTSUPP;
6d5786a3	559	unsigned int xid;
7ffec372 JL	560	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
7ffec372 JL	561	struct tcon_link *tlink;
96daf2b0	562	struct cifs_tcon *pTcon;
1da177e4 LT	563	char *full_path = NULL;
	564	struct inode *newinode = NULL;
	565
6d5786a3	566	xid = get_xid();
1da177e4	567
7ffec372 JL	568	tlink = cifs_sb_tlink(cifs_sb);
	569	if (IS_ERR(tlink)) {
	570	rc = PTR_ERR(tlink);
	571	goto symlink_exit;
	572	}
	573	pTcon = tlink_tcon(tlink);
1da177e4	574
7f57356b	575	full_path = build_path_from_dentry(direntry);
fb8c4b14	576	if (full_path == NULL) {
0f3bc09e	577	rc = -ENOMEM;
7ffec372	578	goto symlink_exit;
1da177e4 LT	579	}
1da177e4 LT	580
b6b38f70 JP	581	cFYI(1, "Full path: %s", full_path);
b6b38f70 JP	582	cFYI(1, "symname is %s", symname);
1da177e4 LT	583
1da177e4 LT	584	/* BB what if DFS and this volume is on different share? BB */
1b12b9c1 SM	585	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
1b12b9c1 SM	586	rc = CIFSCreateMFSymLink(xid, pTcon, full_path, symname,
3d3ea8e6	587	cifs_sb);
1b12b9c1	588	else if (pTcon->unix_ext)
1da177e4 LT	589	rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname,
	590	cifs_sb->local_nls);
	591	/* else
fb8c4b14 SF	592	rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName,
fb8c4b14 SF	593	cifs_sb_target->local_nls); */
1da177e4 LT	594
1da177e4 LT	595	if (rc == 0) {
c18c842b	596	if (pTcon->unix_ext)
1da177e4	597	rc = cifs_get_inode_info_unix(&newinode, full_path,
fb8c4b14	598	inode->i_sb, xid);
1da177e4 LT	599	else
1da177e4 LT	600	rc = cifs_get_inode_info(&newinode, full_path, NULL,
8b1327f6	601	inode->i_sb, xid, NULL);
1da177e4 LT	602
1da177e4 LT	603	if (rc != 0) {
b6b38f70 JP	604	cFYI(1, "Create symlink ok, getinodeinfo fail rc = %d",
b6b38f70 JP	605	rc);
1da177e4	606	} else {
1da177e4 LT	607	d_instantiate(direntry, newinode);
	608	}
	609	}
7ffec372	610	symlink_exit:
f99d49ad	611	kfree(full_path);
7ffec372	612	cifs_put_tlink(tlink);
6d5786a3	613	free_xid(xid);
1da177e4 LT	614	return rc;
	615	}
	616
cc314eef	617	void cifs_put_link(struct dentry direntry, struct nameidata nd, void *cookie)
1da177e4 LT	618	{
	619	char *p = nd_get_link(nd);
	620	if (!IS_ERR(p))
	621	kfree(p);
	622	}