From 90d2c51dbb4db05c040bc7db264bb7ab35e35455 Mon Sep 17 00:00:00 2001 From: Miao Xie Date: Thu, 25 Mar 2010 12:37:12 +0000 Subject: [PATCH] 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 Signed-off-by: Chris Mason --- fs/btrfs/extent-tree.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 1727b26fb194..503a18eaef52 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -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; -- GitLab