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 DBA99FA3728 for ; Wed, 16 Oct 2019 16:06:51 +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 B17982067D for ; Wed, 16 Oct 2019 16:06:51 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B17982067D 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]:45106 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iKlp4-0007AB-H9 for qemu-devel@archiver.kernel.org; Wed, 16 Oct 2019 12:06:50 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:57507) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iKlkm-0003wq-Nn for qemu-devel@nongnu.org; Wed, 16 Oct 2019 12:02:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iKlkh-0008DE-HF for qemu-devel@nongnu.org; Wed, 16 Oct 2019 12:02:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44600) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iKlkh-0008Co-Ab for qemu-devel@nongnu.org; Wed, 16 Oct 2019 12:02:19 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7D5BB7FDF5 for ; Wed, 16 Oct 2019 16:02:18 +0000 (UTC) Received: from localhost (unknown [10.36.118.69]) by smtp.corp.redhat.com (Postfix) with ESMTP id 686C360C80; Wed, 16 Oct 2019 16:02:06 +0000 (UTC) From: Stefan Hajnoczi To: qemu-devel@nongnu.org Subject: [PATCH 1/2] virtiofsd: move to an empty network namespace Date: Wed, 16 Oct 2019 17:01:56 +0100 Message-Id: <20191016160157.12414-2-stefanha@redhat.com> In-Reply-To: <20191016160157.12414-1-stefanha@redhat.com> References: <20191016160157.12414-1-stefanha@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Wed, 16 Oct 2019 16:02:18 +0000 (UTC) Content-Transfer-Encoding: quoted-printable X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.132.183.28 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: virtio-fs@redhat.com, "Dr. David Alan Gilbert" , Stefan Hajnoczi Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" If the process is compromised there should be no network access. Use an empty network namespace to sandbox networking. Signed-off-by: Stefan Hajnoczi --- contrib/virtiofsd/passthrough_ll.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/contrib/virtiofsd/passthrough_ll.c b/contrib/virtiofsd/passt= hrough_ll.c index 84b60d85bd..c27ff7d800 100644 --- a/contrib/virtiofsd/passthrough_ll.c +++ b/contrib/virtiofsd/passthrough_ll.c @@ -2736,6 +2736,19 @@ static void setup_shared_versions(struct lo_data *= lo) lo->version_table =3D addr; } =20 +/* + * Called after our UNIX domain sockets have been created, now we can mo= ve to + * an empty network namespace to prevent TCP/IP and other network activi= ty in + * case this process is compromised. + */ +static void setup_net_namespace(void) +{ + if (unshare(CLONE_NEWNET) !=3D 0) { + fuse_log(FUSE_LOG_ERR, "unshare(CLONE_NEWNET): %m\n"); + exit(1); + } +} + /* This magic is based on lxc's lxc_pivot_root() */ static void setup_pivot_root(const char *source) { @@ -2818,6 +2831,7 @@ static void setup_mount_namespace(const char *sourc= e) */ static void setup_sandbox(struct lo_data *lo, bool enable_syslog) { + setup_net_namespace(); setup_mount_namespace(lo->source); setup_seccomp(enable_syslog); } --=20 2.21.0