From patchwork Thu Jan 23 11:57:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: "Dr. David Alan Gilbert" X-Patchwork-Id: 1227989 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=nongnu.org (client-ip=209.51.188.17; helo=lists.gnu.org; envelope-from=qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=XfxchuaJ; dkim-atps=neutral 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 ozlabs.org (Postfix) with ESMTPS id 483Nwd3Wxtz9sP3 for ; Fri, 24 Jan 2020 00:51:29 +1100 (AEDT) Received: from localhost ([::1]:57318 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iuctK-00070t-Pz for incoming@patchwork.ozlabs.org; Thu, 23 Jan 2020 08:51:26 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:40869) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1iub9Q-0002sf-Qq for qemu-devel@nongnu.org; Thu, 23 Jan 2020 06:59:57 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1iub9P-0005Qc-Mw for qemu-devel@nongnu.org; Thu, 23 Jan 2020 06:59:56 -0500 Received: from us-smtp-delivery-1.mimecast.com ([207.211.31.120]:22770 helo=us-smtp-1.mimecast.com) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1iub9P-0005Q5-Ja for qemu-devel@nongnu.org; Thu, 23 Jan 2020 06:59:55 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1579780794; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=RDwnMarMFxkMHMmMXy+4GSNCt3/pMR742Itw5upomBw=; b=XfxchuaJWnEdgSm9e0p3CTlQ12DkF8qXFRdYeyOE6/Jjl0SaAKj5ZBTShsGYlVQgtxGHs7 s17DopTuJTgwD8a98m85FClA/ibXmiofcUrw3mBYxXCw16ojy+6hBnM9+dJrklWRUIsuFz l7KCyqQaRMFY5NfLouy0vDWFLGu76mo= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-137-wVe6QFJhMu2PbL5AFwFH7w-1; Thu, 23 Jan 2020 06:59:47 -0500 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E63528017CC for ; Thu, 23 Jan 2020 11:59:46 +0000 (UTC) Received: from dgilbert-t580.localhost (unknown [10.36.118.0]) by smtp.corp.redhat.com (Postfix) with ESMTP id 37F2B1CB; Thu, 23 Jan 2020 11:59:46 +0000 (UTC) From: "Dr. David Alan Gilbert (git)" To: qemu-devel@nongnu.org, stefanha@redhat.com Subject: [PULL 050/111] virtiofsd: move to an empty network namespace Date: Thu, 23 Jan 2020 11:57:40 +0000 Message-Id: <20200123115841.138849-51-dgilbert@redhat.com> In-Reply-To: <20200123115841.138849-1-dgilbert@redhat.com> References: <20200123115841.138849-1-dgilbert@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-MC-Unique: wVe6QFJhMu2PbL5AFwFH7w-1 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 207.211.31.120 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: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: "Qemu-devel" From: Stefan Hajnoczi If the process is compromised there should be no network access. Use an empty network namespace to sandbox networking. Signed-off-by: Stefan Hajnoczi Reviewed-by: Daniel P. Berrangé Signed-off-by: Dr. David Alan Gilbert --- tools/virtiofsd/passthrough_ll.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/tools/virtiofsd/passthrough_ll.c b/tools/virtiofsd/passthrough_ll.c index 0570453eef..27ab328722 100644 --- a/tools/virtiofsd/passthrough_ll.c +++ b/tools/virtiofsd/passthrough_ll.c @@ -1944,6 +1944,19 @@ static void print_capabilities(void) printf("}\n"); } +/* + * Called after our UNIX domain sockets have been created, now we can move to + * an empty network namespace to prevent TCP/IP and other network activity in + * case this process is compromised. + */ +static void setup_net_namespace(void) +{ + if (unshare(CLONE_NEWNET) != 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) { @@ -2035,6 +2048,7 @@ static void setup_mount_namespace(const char *source) */ static void setup_sandbox(struct lo_data *lo) { + setup_net_namespace(); setup_mount_namespace(lo->source); }