btrfs: fix oops on failure path

If lookup_extent_backref fails, path->nodes[0] reasonably could be
null along with other callers of btrfs_print_leaf, so ensure we have a
valid extent buffer before dereferencing.

Signed-off-by: Daniel J Blueman <daniel.blueman@gmail.com>
This commit is contained in:
Daniel J Blueman 2011-06-23 23:01:01 +08:00 committed by David Sterba
parent 60d2adbb1e
commit 068132bad1

View File

@ -158,8 +158,7 @@ static void print_extent_ref_v0(struct extent_buffer *eb, int slot)
void btrfs_print_leaf(struct btrfs_root *root, struct extent_buffer *l)
{
int i;
u32 type;
u32 nr = btrfs_header_nritems(l);
u32 type, nr;
struct btrfs_item *item;
struct btrfs_root_item *ri;
struct btrfs_dir_item *di;
@ -172,6 +171,11 @@ void btrfs_print_leaf(struct btrfs_root *root, struct extent_buffer *l)
struct btrfs_key key;
struct btrfs_key found_key;
if (!l)
return;
nr = btrfs_header_nritems(l);
printk(KERN_INFO "leaf %llu total ptrs %d free space %d\n",
(unsigned long long)btrfs_header_bytenr(l), nr,
btrfs_leaf_free_space(root, l));