diff -uNr linux-2.6.23.9/drivers/md/dm.c linux-2.6.23.9-new/drivers/md/dm.c
--- linux-2.6.23.9/drivers/md/dm.c	2007-11-26 12:51:43.000000000 -0500
+++ linux-2.6.23.9-new/drivers/md/dm.c	2007-11-28 10:07:20.376734456 -0500
@@ -652,6 +652,13 @@
 	struct bio *clone;
 
 	clone = bio_alloc_bioset(GFP_NOIO, bio->bi_max_vecs, bs);
+
+	/*
+	 * bio_alloc_bioset could return NULL.
+	 */
+	if(!clone)
+		return clone;
+
 	__bio_clone(clone, bio);
 	clone->bi_destructor = dm_bio_destructor;
 	clone->bi_sector = sector;