Commit 21643e69 authored Nov 04, 2011 by Dan Carpenter Committed by Konrad Rzeszutek Wilk Nov 16, 2011

xen-gntalloc: integer overflow in gntalloc_ioctl_alloc()



On 32 bit systems a high value of op.count could lead to an integer
overflow in the kzalloc() and gref_ids would be smaller than
expected.  If the you triggered another integer overflow in
"if (gref_size + op.count > limit)" then you'd probably get memory
corruption inside add_grefs().

CC: stable@kernel.org
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

parent fc6e0c3b

drivers/xen/gntalloc.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -280,7 +280,7 @@ static long gntalloc_ioctl_alloc(struct gntalloc_file_private_data *priv,
		goto out;
		}

		gref_ids = kzalloc(sizeof(gref_ids[0]) * op.count, GFP_TEMPORARY);
		gref_ids = kcalloc(op.count, sizeof(gref_ids[0]), GFP_TEMPORARY);
		if (!gref_ids) {
		rc = -ENOMEM;
		goto out;