Commit 7f43d4af authored Aug 23, 2017 by Qu Wenruo Committed by David Sterba Oct 30, 2017

btrfs: Check if item pointer overlaps with the item itself



Function check_leaf() checks if any item pointer points outside of the
leaf, but it doesn't check if the pointer overlaps with the item itself.

Normally only the last item may be the victim, but adding such check is
never a bad idea anyway.

Signed-off-by: Qu Wenruo <quwenruo.btrfs@gmx.com>
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

parent c3267bba

fs/btrfs/disk-io.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -643,6 +643,13 @@ static noinline int check_leaf(struct btrfs_root *root,
		return -EUCLEAN;
		}

		/* Also check if the item pointer overlaps with btrfs item. */
		if (btrfs_item_nr_offset(slot) + sizeof(struct btrfs_item) >
		btrfs_item_ptr_offset(leaf, slot)) {
		CORRUPT("slot overlap with its data", leaf, root, slot);
		return -EUCLEAN;
		}

		prev_key.objectid = key.objectid;
		prev_key.type = key.type;
		prev_key.offset = key.offset;

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