From patchwork Wed Aug 2 22:26:07 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Samuel Thibault X-Patchwork-Id: 796905 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=nongnu.org (client-ip=2001:4830:134:3::11; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3xN78R2Fttz9s9Y for ; Thu, 3 Aug 2017 08:26:47 +1000 (AEST) Received: from localhost ([::1]:50785 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dd26H-0003LN-7K for incoming@patchwork.ozlabs.org; Wed, 02 Aug 2017 18:26:45 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60177) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dd25o-0003Ky-Sr for qemu-devel@nongnu.org; Wed, 02 Aug 2017 18:26:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dd25k-0003sW-OL for qemu-devel@nongnu.org; Wed, 02 Aug 2017 18:26:16 -0400 Received: from sonata.ens-lyon.org ([140.77.166.138]:55803) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dd25k-0003r3-I5 for qemu-devel@nongnu.org; Wed, 02 Aug 2017 18:26:12 -0400 Received: from localhost (localhost [127.0.0.1]) by sonata.ens-lyon.org (Postfix) with ESMTP id 1A4B6200E4; Thu, 3 Aug 2017 00:26:10 +0200 (CEST) Received: from sonata.ens-lyon.org ([127.0.0.1]) by localhost (sonata.ens-lyon.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id YZPyCT-2uKEj; Thu, 3 Aug 2017 00:26:10 +0200 (CEST) Received: from var.youpi.perso.aquilenet.fr (LFbn-1-6903-179.w90-120.abo.wanadoo.fr [90.120.90.179]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sonata.ens-lyon.org (Postfix) with ESMTPSA id 80908200DB; Thu, 3 Aug 2017 00:26:09 +0200 (CEST) Received: from samy by var.youpi.perso.aquilenet.fr with local (Exim 4.89) (envelope-from ) id 1dd25g-0008MG-Tp; Thu, 03 Aug 2017 00:26:08 +0200 From: Samuel Thibault To: qemu-devel@nongnu.org Date: Thu, 3 Aug 2017 00:26:07 +0200 Message-Id: <20170802222607.32085-3-samuel.thibault@ens-lyon.org> X-Mailer: git-send-email 2.13.2 In-Reply-To: <20170802222607.32085-1-samuel.thibault@ens-lyon.org> References: <20170802222607.32085-1-samuel.thibault@ens-lyon.org> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 140.77.166.138 Subject: [Qemu-devel] [PULL 2/2] 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: jan.kiszka@siemens.com, Prasad J Pandit , stefanha@redhat.com, Samuel Thibault Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" 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 Signed-off-by: Samuel Thibault --- slirp/bootp.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/slirp/bootp.c b/slirp/bootp.c index 5a4646c182..5dd1a415b5 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) {