CIFS: Fix ERR_PTR dereference in cifs_get_root

commit 5b980b01212199833ee8023770fa4cbf1b85e9f4 upstream.

move it to the beginning of the loop.

Signed-off-by: Pavel Shilovsky <piastryyy@gmail.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
Cc: Josh Boyer <jwboyer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index fc7e57b3f38567a5625fce16695c9a6214c5d7cd..53e7d72177d2853ece3e2612351c08b0ed2a4952 100644 (file)
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -566,6 +566,12 @@ cifs_get_root(struct smb_vol *vol, struct super_block *sb)
                struct inode *dir = dentry->d_inode;
                struct dentry *child;
 
+               if (!dir) {
+                       dput(dentry);
+                       dentry = ERR_PTR(-ENOENT);
+                       break;
+               }
+
                /* skip separators */
                while (*s == sep)
                        s++;
@@ -581,10 +587,6 @@ cifs_get_root(struct smb_vol *vol, struct super_block *sb)
                mutex_unlock(&dir->i_mutex);
                dput(dentry);
                dentry = child;
-               if (!dentry->d_inode) {
-                       dput(dentry);
-                       dentry = ERR_PTR(-ENOENT);
-               }
        } while (!IS_ERR(dentry));
        _FreeXid(xid);
        kfree(full_path);