From patchwork Mon Jul 17 12:03:26 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Prasad Pandit X-Patchwork-Id: 9844785 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 0847360386 for ; Mon, 17 Jul 2017 12:06:42 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EEA2A2823D for ; Mon, 17 Jul 2017 12:06:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E2ED3284F4; Mon, 17 Jul 2017 12:06:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 77FB62823D for ; Mon, 17 Jul 2017 12:06:41 +0000 (UTC) Received: from localhost ([::1]:49921 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dX4nQ-0000ZW-Dj for patchwork-qemu-devel@patchwork.kernel.org; Mon, 17 Jul 2017 08:06:40 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41418) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dX4kU-0006op-14 for qemu-devel@nongnu.org; Mon, 17 Jul 2017 08:03:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dX4kQ-00071t-VT for qemu-devel@nongnu.org; Mon, 17 Jul 2017 08:03:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42086) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dX4kQ-00070U-QC for qemu-devel@nongnu.org; Mon, 17 Jul 2017 08:03:34 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id D9C1E7CB90; Mon, 17 Jul 2017 12:03:32 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com D9C1E7CB90 Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx02.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=ppandit@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com D9C1E7CB90 Received: from localhost.localdomain (ovpn-116-83.sin2.redhat.com [10.67.116.83]) by smtp.corp.redhat.com (Postfix) with ESMTPS id CD8354DA72; Mon, 17 Jul 2017 12:03:30 +0000 (UTC) From: P J P To: Qemu Developers Date: Mon, 17 Jul 2017 17:33:26 +0530 Message-Id: <20170717120326.27967-1-ppandit@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Mon, 17 Jul 2017 12:03:33 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH] slirp: check len against dhcp options array end X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Samuel Thibault , Reno Robert , Prasad J Pandit , Jan Kiszka Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Prasad J Pandit While parsing dhcp options string in 'dhcp_decode', if an options' length 'len' appeared towards the end of 'bp_vend' array, ensuing read could lead to an OOB memory access issue. Add check to avoid it. Reported-by: Reno Robert Signed-off-by: Prasad J Pandit --- slirp/bootp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/slirp/bootp.c b/slirp/bootp.c index 5a4646c..5dd1a41 100644 --- a/slirp/bootp.c +++ b/slirp/bootp.c @@ -123,6 +123,9 @@ static void dhcp_decode(const struct bootp_t *bp, int *pmsg_type, if (p >= p_end) break; len = *p++; + if (p + len > p_end) { + break; + } DPRINTF("dhcp: tag=%d len=%d\n", tag, len); switch(tag) {