From: Josef Bacik josef@toxicpanda.com
commit d7c9e1be2876f63fb2178a24e0c1d5733ff98d47 upstream.
I don't know how this isn't caught when we build this in the kernel, but while syncing extent-io-tree.c into btrfs-progs I got an error because parent could potentially be uninitialized when we link in a new node, specifically when the extent_io_tree is empty. This means we could have garbage in the parent color. I don't know what the ramifications are of that, but it's probably not great, so fix this by initializing parent to NULL. I spot checked all of our other usages in btrfs and we appear to be doing the correct thing everywhere else.
Fixes: c7e118cf98c7 ("btrfs: open code rbtree search in insert_state") CC: stable@vger.kernel.org # 6.0+ Signed-off-by: Josef Bacik josef@toxicpanda.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/extent-io-tree.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/btrfs/extent-io-tree.c +++ b/fs/btrfs/extent-io-tree.c @@ -397,7 +397,7 @@ static int insert_state(struct extent_io u32 bits, struct extent_changeset *changeset) { struct rb_node **node; - struct rb_node *parent; + struct rb_node *parent = NULL; const u64 end = state->end;
set_state_bits(tree, state, bits, changeset);