Currently scrub only verify checksum of both metadata and data and couldn't detect an invalid extent_item.
This adds sanity check for extent item, now it can check if extent_inline_ref_type is valid. Signed-off-by: Liu Bo <bo.li....@oracle.com> --- fs/btrfs/scrub.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index b0251eb..e87b752 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -3058,6 +3058,39 @@ static noinline_for_stack int scrub_raid56_parity(struct scrub_ctx *sctx, return ret < 0 ? ret : 0; } +static int check_extent_item(struct extent_buffer *l, int slot, + struct btrfs_extent_item *ei, int key_type) +{ + unsigned long ptr; + unsigned long end; + struct btrfs_extent_inline_ref *iref; + u64 flags = btrfs_extent_flags(l, ei); + int is_data = !!(flags & BTRFS_EXTENT_FLAG_DATA); + int type; + + ptr = (unsigned long)(ei + 1); + if (!is_data && + key_type != BTRFS_METADATA_ITEM_KEY) + ptr += sizeof(struct btrfs_tree_block_info); + end = (unsigned long)ei + + btrfs_item_size_nr(l, slot); + + while (1) { + if (ptr >= end) { + WARN_ON(ptr > end); + break; + } + + iref = (struct btrfs_extent_inline_ref *)ptr; + type = btrfs_get_extent_inline_ref_type(l, iref, is_data); + if (type < 0) + return type; + + ptr += btrfs_extent_inline_ref_size(type); + } + return 0; +} + static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx, struct map_lookup *map, struct btrfs_device *scrub_dev, @@ -3318,6 +3351,16 @@ static noinline_for_stack int scrub_stripe(struct scrub_ctx *sctx, goto next; } + /* sanity check for extent inline ref type */ + if (check_extent_item(l, slot, extent, key.type)) { + btrfs_err(fs_info, + "scrub: extent %llu(0x%llx) has an invalid extent inline ref type, ignored.", + key.objectid, key.objectid); + spin_lock(&sctx->stat_lock); + sctx->stat.uncorrectable_errors++; + spin_unlock(&sctx->stat_lock); + goto next; + } again: extent_logical = key.objectid; extent_len = bytes; -- 2.9.4 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html