4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Liu Bo bo.li.liu@oracle.com
commit 6b722c1747d533ac6d4df110dc8233db46918b65 upstream.
We need to check items in a node to make sure that we're reading a valid one, otherwise we could get various crashes while processing delayed_refs.
Signed-off-by: Liu Bo bo.li.liu@oracle.com Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Ben Hutchings ben.hutchings@codethink.co.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/disk-io.c | 32 ++++++++++++++++++++++++++++---- 1 file changed, 28 insertions(+), 4 deletions(-)
--- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -523,9 +523,10 @@ static int check_tree_block_fsid(struct }
#define CORRUPT(reason, eb, root, slot) \ - btrfs_crit(root->fs_info, "corrupt leaf, %s: block=%llu," \ - "root=%llu, slot=%d", reason, \ - btrfs_header_bytenr(eb), root->objectid, slot) + btrfs_crit(root->fs_info, "corrupt %s, %s: block=%llu," \ + " root=%llu, slot=%d", \ + btrfs_header_level(eb) == 0 ? "leaf" : "node",\ + reason, btrfs_header_bytenr(eb), root->objectid, slot)
static noinline int check_leaf(struct btrfs_root *root, struct extent_buffer *leaf) @@ -616,6 +617,10 @@ static noinline int check_leaf(struct bt static int check_node(struct btrfs_root *root, struct extent_buffer *node) { unsigned long nr = btrfs_header_nritems(node); + struct btrfs_key key, next_key; + int slot; + u64 bytenr; + int ret = 0;
if (nr == 0 || nr > BTRFS_NODEPTRS_PER_BLOCK(root)) { btrfs_crit(root->fs_info, @@ -623,7 +628,26 @@ static int check_node(struct btrfs_root node->start, root->objectid, nr); return -EIO; } - return 0; + + for (slot = 0; slot < nr - 1; slot++) { + bytenr = btrfs_node_blockptr(node, slot); + btrfs_node_key_to_cpu(node, &key, slot); + btrfs_node_key_to_cpu(node, &next_key, slot + 1); + + if (!bytenr) { + CORRUPT("invalid item slot", node, root, slot); + ret = -EIO; + goto out; + } + + if (btrfs_comp_cpu_keys(&key, &next_key) >= 0) { + CORRUPT("bad key order", node, root, slot); + ret = -EIO; + goto out; + } + } +out: + return ret; }
static int btree_readpage_end_io_hook(struct btrfs_io_bio *io_bio,