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>
This commit is contained in:
Miao Xie 2010-03-25 12:37:12 +00:00 committed by Chris Mason
parent 2f3014fc2a
commit 90d2c51dbb

View file

@ -5205,6 +5205,8 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans,
next = btrfs_find_tree_block(root, bytenr, blocksize);
if (!next) {
next = btrfs_find_create_tree_block(root, bytenr, blocksize);
if (!next)
return -ENOMEM;
reada = 1;
}
btrfs_tree_lock(next);
@ -5417,7 +5419,8 @@ static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
if (ret > 0) {
path->slots[level]++;
continue;
}
} else if (ret < 0)
return ret;
level = wc->level;
}
return 0;