Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965205Ab3CZPyJ (ORCPT ); Tue, 26 Mar 2013 11:54:09 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:53757 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965023Ab3CZPWe (ORCPT ); Tue, 26 Mar 2013 11:22:34 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: "Michael S. Tsirkin" , "David S. Miller" , Luis Henriques Subject: [PATCH 059/150] vhost/net: fix heads usage of ubuf_info Date: Tue, 26 Mar 2013 15:19:18 +0000 Message-Id: <1364311249-14454-60-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1364311249-14454-1-git-send-email-luis.henriques@canonical.com> References: <1364311249-14454-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1476 Lines: 43 3.5.7.9 -stable review patch. If anyone has any objections, please let me know. ------------------ From: "Michael S. Tsirkin" commit 46aa92d1ba162b4b3d6b7102440e459d4e4ee255 upstream. ubuf info allocator uses guest controlled head as an index, so a malicious guest could put the same head entry in the ring twice, and we will get two callbacks on the same value. To fix use upend_idx which is guaranteed to be unique. Reported-by: Rusty Russell Signed-off-by: Michael S. Tsirkin Signed-off-by: David S. Miller Signed-off-by: Luis Henriques --- drivers/vhost/net.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/vhost/net.c b/drivers/vhost/net.c index 3c4dcc3d9..f2e8236 100644 --- a/drivers/vhost/net.c +++ b/drivers/vhost/net.c @@ -235,7 +235,8 @@ static void handle_tx(struct vhost_net *net) msg.msg_controllen = 0; ubufs = NULL; } else { - struct ubuf_info *ubuf = &vq->ubuf_info[head]; + struct ubuf_info *ubuf; + ubuf = vq->ubuf_info + vq->upend_idx; vq->heads[vq->upend_idx].len = len; ubuf->callback = vhost_zerocopy_callback; -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/