From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755606AbaC0KxU (ORCPT ); Thu, 27 Mar 2014 06:53:20 -0400 Received: from mx1.redhat.com ([209.132.183.28]:12423 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754594AbaC0KxS (ORCPT ); Thu, 27 Mar 2014 06:53:18 -0400 Date: Thu, 27 Mar 2014 12:53:37 +0200 From: "Michael S. Tsirkin" To: linux-kernel@vger.kernel.org Cc: kvm@vger.kernel.org, virtio-dev@lists.oasis-open.org, virtualization@lists.linux-foundation.org, netdev@vger.kernel.org, David Miller , Jason Wang Subject: [PATCH net] vhost: validate vhost_get_vq_desc return value Message-ID: <1395917517-30937-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline X-Mutt-Fcc: =sent Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org vhost fails to validate negative error code from vhost_get_vq_desc causing a crash: we are using -EFAULT which is 0xfffffff2 as vector size, which exceeds the allocated size. The code in question was introduced in commit 8dd014adfea6f173c1ef6378f7e5e7924866c923 vhost-net: mergeable buffers support CVE-2014-0055 Signed-off-by: Michael S. Tsirkin --- This is needed in -stable. drivers/vhost/net.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 026be58..e1e22e0 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -505,9 +505,13 @@ static int get_rx_bufs(struct vhost_virtqueue *vq, r = -ENOBUFS; goto err; } - d = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, + r = vhost_get_vq_desc(vq->dev, vq, vq->iov + seg, ARRAY_SIZE(vq->iov) - seg, &out, &in, log, log_num); + if (unlikely(r < 0)) + goto err; + + d = r; if (d == vq->num) { r = 0; goto err; -- MST