From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6EB82C3A5A1 for ; Thu, 22 Aug 2019 14:43:31 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 48B43233A1 for ; Thu, 22 Aug 2019 14:43:31 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 48B43233A1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:44016 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i0oJG-0005r1-Hl for qemu-devel@archiver.kernel.org; Thu, 22 Aug 2019 10:43:30 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:34424) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i0oHf-00045l-3p for qemu-devel@nongnu.org; Thu, 22 Aug 2019 10:41:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i0oHe-0002oz-5w for qemu-devel@nongnu.org; Thu, 22 Aug 2019 10:41:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38220) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i0oHd-0002oD-Vw; Thu, 22 Aug 2019 10:41:50 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 44544308FC4E; Thu, 22 Aug 2019 14:41:49 +0000 (UTC) Received: from x1w.redhat.com (unknown [10.40.205.175]) by smtp.corp.redhat.com (Postfix) with ESMTPS id BECCB5D6A7; Thu, 22 Aug 2019 14:41:46 +0000 (UTC) From: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= To: slirp@lists.freedesktop.org Date: Thu, 22 Aug 2019 16:41:34 +0200 Message-Id: <20190822144134.23521-3-philmd@redhat.com> In-Reply-To: <20190822144134.23521-1-philmd@redhat.com> References: <20190822144134.23521-1-philmd@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.43]); Thu, 22 Aug 2019 14:41:49 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [RFC PATCH 2/2] Delay crash when mbufs are corrupted X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: =?UTF-8?q?Philippe=20Mathieu-Daud=C3=A9?= , qemu-stable@nongnu.org, Petr Matousek , qemu-devel@nongnu.org, Prasad J Pandit Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" If the mbufs linked list is corrupted, give the application a chance to properly shutdown itself without causing dataloss. For now, this means slowly leaking the heap. Signed-off-by: Philippe Mathieu-Daud=C3=A9 --- src/ip_input.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/src/ip_input.c b/src/ip_input.c index ee52085..36962b5 100644 --- a/src/ip_input.c +++ b/src/ip_input.c @@ -185,6 +185,15 @@ void ip_input(struct mbuf *m) if (ip =3D=3D NULL) return; m =3D dtom(slirp, ip); + if (m =3D=3D NULL) { + /* The mbufs linked list is corrupted, we + * should properly shutdown the application. + * We prefer to leak a mbuf on the heap + * rather than allowing null dereference + * and eventual crash (data corruption). + */ + return; /* TODO warn the library consumer! */ + } } else if (fp) ip_freef(slirp, fp); =20 --=20 2.20.1