ext4: return error when calling ext4_ext_split failed

ext4_ext_create_new_leaf must return error when its
calling to ext4_ext_split failed.
Signed-off-by: NShen Feng <shen@cn.fujitsu.com>
Signed-off-by: NMingming Cao <cmm@us.ibm.com>
Reviewed-by: NAneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>

fs/ext4/extents.c

@@ -981,6 +981,8 @@ static int ext4_ext_create_new_leaf(handle_t *handle, struct inode *inode,
 		/* if we found index with free entry, then use that
 		 * entry: create all needed subtree and add new leaf */
 		err = ext4_ext_split(handle, inode, path, newext, i);
+		if (err)
+			goto out;
 
 		/* refill path */
 		ext4_ext_drop_refs(path);