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=-6.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_SBL,URIBL_SBL_A 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 B6C02C0650E for ; Mon, 1 Jul 2019 09:17:54 +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 8ED5B213F2 for ; Mon, 1 Jul 2019 09:17:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8ED5B213F2 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]:56280 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hhsRd-0002o9-MC for qemu-devel@archiver.kernel.org; Mon, 01 Jul 2019 05:17:53 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45234) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hhsLW-00055w-Af for qemu-devel@nongnu.org; Mon, 01 Jul 2019 05:11:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hhsLU-0007kY-QD for qemu-devel@nongnu.org; Mon, 01 Jul 2019 05:11:34 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39704) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hhsLU-0007VH-Kp for qemu-devel@nongnu.org; Mon, 01 Jul 2019 05:11:32 -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 262BB13A41; Mon, 1 Jul 2019 09:11:15 +0000 (UTC) Received: from localhost.localdomain (unknown [10.33.36.5]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 558AF17502; Mon, 1 Jul 2019 09:11:12 +0000 (UTC) From: P J P To: Qemu Developers Date: Mon, 1 Jul 2019 14:39:02 +0530 Message-Id: <20190701090904.31312-2-ppandit@redhat.com> In-Reply-To: <20190701090904.31312-1-ppandit@redhat.com> References: <20190701090904.31312-1-ppandit@redhat.com> MIME-Version: 1.0 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 [10.5.110.29]); Mon, 01 Jul 2019 09:11:15 +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] [PATCH v2 1/3] qemu-bridge-helper: restrict interface name to IFNAMSIZ 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: Riccardo Schirone , =?UTF-8?q?Daniel=20P=20=2E=20Berrang=C3=A9?= , Jason Wang , Li Qiang , Prasad J Pandit Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" From: Prasad J Pandit The interface names in qemu-bridge-helper are defined to be of size IFNAMSIZ(=3D16), including the terminating null('\0') byte. The same is applied to interface names read from 'bridge.conf' file to form ACLs rules. If user supplied '--br=3Dbridge' name is not restricted to the same length, it could lead to ACL bypass issue. Restrict interface name to IFNAMSIZ, including null byte. Reported-by: Riccardo Schirone Signed-off-by: Prasad J Pandit --- qemu-bridge-helper.c | 11 +++++++++++ 1 file changed, 11 insertions(+) Update v2: report an error and exit -> https://lists.gnu.org/archive/html/qemu-devel/2019-06/msg06239.html diff --git a/qemu-bridge-helper.c b/qemu-bridge-helper.c index f9940deefd..8ec0a65174 100644 --- a/qemu-bridge-helper.c +++ b/qemu-bridge-helper.c @@ -109,6 +109,13 @@ static int parse_acl_file(const char *filename, ACLL= ist *acl_list) } *argend =3D 0; =20 + if (strcmp(cmd, "include") && strlen(arg) >=3D IFNAMSIZ) { + fprintf(stderr, "name `%s' too long: %lu\n", arg, strlen(arg= )); + fclose(f); + errno =3D EINVAL; + return -1; + } + if (strcmp(cmd, "deny") =3D=3D 0) { acl_rule =3D g_malloc(sizeof(*acl_rule)); if (strcmp(arg, "all") =3D=3D 0) { @@ -259,6 +266,10 @@ int main(int argc, char **argv) usage(); return EXIT_FAILURE; } + if (strlen(bridge) >=3D IFNAMSIZ) { + fprintf(stderr, "name `%s' too long: %lu\n", bridge, strlen(brid= ge)); + return EXIT_FAILURE; + } =20 /* parse default acl file */ QSIMPLEQ_INIT(&acl_list); --=20 2.21.0