tree d97b50f0a064366aecce9671b8e1791263999e59
parent 2f3014fc2ab1e25c36531e19164c48182c168995
author Miao Xie <miaox@cn.fujitsu.com> 1269520632 +0000
committer Chris Mason <chris.mason@oracle.com> 1269998348 -0400

Btrfs: add NULL check for do_walk_down()

btrfs_find_create_tree_block() may return NULL, so we must check the returned
value, or we will access a NULL pointer.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>