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.liu@xxxxxxxxxx>
---
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
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