btrfs: tree-checker: check item_size for dev_item

commit ea1d1ca402 upstream.

Check item size before accessing the device item to avoid out of bound
access, similar to inode_item check.

Signed-off-by: Su Yue <l@damenly.su>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Su Yue 2022-01-21 17:33:35 +08:00 committed by Greg Kroah-Hartman
parent 7e80846a99
commit b80fbc20f3
1 changed files with 8 additions and 0 deletions

View File

@ -965,6 +965,7 @@ static int check_dev_item(struct extent_buffer *leaf,
struct btrfs_key *key, int slot)
{
struct btrfs_dev_item *ditem;
const u32 item_size = btrfs_item_size_nr(leaf, slot);
if (unlikely(key->objectid != BTRFS_DEV_ITEMS_OBJECTID)) {
dev_item_err(leaf, slot,
@ -972,6 +973,13 @@ static int check_dev_item(struct extent_buffer *leaf,
key->objectid, BTRFS_DEV_ITEMS_OBJECTID);
return -EUCLEAN;
}
if (unlikely(item_size != sizeof(*ditem))) {
dev_item_err(leaf, slot, "invalid item size: has %u expect %zu",
item_size, sizeof(*ditem));
return -EUCLEAN;
}
ditem = btrfs_item_ptr(leaf, slot, struct btrfs_dev_item);
if (unlikely(btrfs_device_id(leaf, ditem) != key->offset)) {
dev_item_err(leaf, slot,