cifs: Fix xid leak in cifs_flock()

[ Upstream commit 575e079 ]

If not flock, before return -ENOLCK, should free the xid,
otherwise, the xid will be leaked.

Fixes: d067799 ("cifs: add support for flock")
Reviewed-by: Paulo Alcantara (SUSE) <pc@cjr.nz>
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

fs/cifs/file.c

@@ -1882,11 +1882,13 @@ int cifs_flock(struct file *file, int cmd, struct file_lock *fl)
 	struct cifsFileInfo *cfile;
 	__u32 type;
 
-	rc = -EACCES;
 	xid = get_xid();
 
-	if (!(fl->fl_flags & FL_FLOCK))
-		return -ENOLCK;
+	if (!(fl->fl_flags & FL_FLOCK)) {
+		rc = -ENOLCK;
+		free_xid(xid);
+		return rc;
+	}
 
 	cfile = (struct cifsFileInfo *)file->private_data;
 	tcon = tlink_tcon(cfile->tlink);
@@ -1905,8 +1907,9 @@ int cifs_flock(struct file *file, int cmd, struct file_lock *fl)
 		 * if no lock or unlock then nothing to do since we do not
 		 * know what it is
 		 */
+		rc = -EOPNOTSUPP;
 		free_xid(xid);
-		return -EOPNOTSUPP;
+		return rc;
 	}
 
 	rc = cifs_setlk(file, fl, type, wait_flag, posix_lck, lock, unlock,