From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754797AbaD1Bbq (ORCPT ); Sun, 27 Apr 2014 21:31:46 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:42823 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752215AbaD1B3V (ORCPT ); Sun, 27 Apr 2014 21:29:21 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Michael S. Tsirkin" , "David S. Miller" Date: Mon, 28 Apr 2014 02:11:21 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 09/94] vhost: validate vhost_get_vq_desc return value In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.58-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: "Michael S. Tsirkin" [ Upstream commit a39ee449f96a2cd44ce056d8a0a112211a9b1a1f ] 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 Signed-off-by: David S. Miller Signed-off-by: Ben Hutchings --- drivers/vhost/net.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -319,9 +319,13 @@ static int get_rx_bufs(struct vhost_virt 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;