Commit 362c4909 authored by Long Li's avatar Long Li Committed by Carlos Maiolino
Browse files

xfs: fix integer overflow in bmap intent sort comparator 



xfs_bmap_update_diff_items() sorts bmap intents by inode number using
a subtraction of two xfs_ino_t (uint64_t) values, with the result
truncated to int. This is incorrect when two inode numbers differ by
more than INT_MAX (2^31 - 1), which is entirely possible on large XFS
filesystems.

Fix this by replacing the subtraction with cmp_int().

Cc: <stable@vger.kernel.org> # v4.9
Fixes: 9f3afb57 ("xfs: implement deferred bmbt map/unmap operations")
Signed-off-by: default avatarLong Li <leo.lilong@huawei.com>
Reviewed-by: default avatarDarrick J. Wong <djwong@kernel.org>
Signed-off-by: default avatarCarlos Maiolino <cem@kernel.org>
parent 52a8a1ba

fs/xfs/xfs_bmap_item.c

+1 −1
Original line number Diff line number Diff line
@@ -245,7 +245,7 @@ xfs_bmap_update_diff_items( 
	struct xfs_bmap_intent		*ba = bi_entry(a);

	struct xfs_bmap_intent		*bb = bi_entry(b);



	return ba->bi_owner->i_ino - bb->bi_owner->i_ino;

	return cmp_int(ba->bi_owner->i_ino, bb->bi_owner->i_ino);

}



/* Log bmap updates in the intent item. */