From patchwork Mon Dec 7 14:17:10 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jason Wang X-Patchwork-Id: 553412 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org 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 EFA43140BAD for ; Tue, 8 Dec 2015 01:21:09 +1100 (AEDT) Received: from localhost ([::1]:54885 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a5wf5-0005iT-Po for incoming@patchwork.ozlabs.org; Mon, 07 Dec 2015 09:21:07 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54204) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a5wcB-0000hK-N3 for qemu-devel@nongnu.org; Mon, 07 Dec 2015 09:18:08 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1a5wc5-0001M4-G1 for qemu-devel@nongnu.org; Mon, 07 Dec 2015 09:18:07 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42419) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1a5wc5-0001Lr-By; Mon, 07 Dec 2015 09:18:01 -0500 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (Postfix) with ESMTPS id E350E5BA1B; Mon, 7 Dec 2015 14:18:00 +0000 (UTC) Received: from jason-ThinkPad-T430s.redhat.com (vpn1-5-152.pek2.redhat.com [10.72.5.152]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id tB7EHK4h032003; Mon, 7 Dec 2015 09:17:52 -0500 From: Jason Wang To: peter.maydell@linaro.org, qemu-devel@nongnu.org Date: Mon, 7 Dec 2015 22:17:10 +0800 Message-Id: <1449497833-15074-4-git-send-email-jasowang@redhat.com> In-Reply-To: <1449497833-15074-1-git-send-email-jasowang@redhat.com> References: <1449497833-15074-1-git-send-email-jasowang@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.27 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: Jason Wang , Prasad J Pandit , qemu-stable@nongnu.org Subject: [Qemu-devel] [PULL V2 for 2.5 3/6] pcnet: fix rx buffer overflow(CVE-2015-7512) X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Backends could provide a packet whose length is greater than buffer size. Check for this and truncate the packet to avoid rx buffer overflow in this case. Cc: Prasad J Pandit Cc: qemu-stable@nongnu.org Reviewed-by: Michael S. Tsirkin Signed-off-by: Jason Wang --- hw/net/pcnet.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/hw/net/pcnet.c b/hw/net/pcnet.c index 309c40b..1f4a3db 100644 --- a/hw/net/pcnet.c +++ b/hw/net/pcnet.c @@ -1064,6 +1064,12 @@ ssize_t pcnet_receive(NetClientState *nc, const uint8_t *buf, size_t size_) int pktcount = 0; if (!s->looptest) { + if (size > 4092) { +#ifdef PCNET_DEBUG_RMD + fprintf(stderr, "pcnet: truncates rx packet.\n"); +#endif + size = 4092; + } memcpy(src, buf, size); /* no need to compute the CRC */ src[size] = 0;