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 CA64BC43613 for ; Fri, 21 Jun 2019 09:41:59 +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 A3BEC21537 for ; Fri, 21 Jun 2019 09:41:59 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A3BEC21537 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]:57468 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1heG3S-0005sh-TK for qemu-devel@archiver.kernel.org; Fri, 21 Jun 2019 05:41:58 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:49454) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1heG23-0004d8-IY for qemu-devel@nongnu.org; Fri, 21 Jun 2019 05:40:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1heG20-0002MG-GX for qemu-devel@nongnu.org; Fri, 21 Jun 2019 05:40:31 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51446) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1heG20-0002LQ-C8 for qemu-devel@nongnu.org; Fri, 21 Jun 2019 05:40:28 -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 5D67A3082E21; Fri, 21 Jun 2019 09:40:27 +0000 (UTC) Received: from localhost (ovpn-117-248.ams2.redhat.com [10.36.117.248]) by smtp.corp.redhat.com (Postfix) with ESMTP id 1F3145C22B; Fri, 21 Jun 2019 09:40:17 +0000 (UTC) From: Stefan Hajnoczi To: Date: Fri, 21 Jun 2019 10:40:02 +0100 Message-Id: <20190621094005.4134-2-stefanha@redhat.com> In-Reply-To: <20190621094005.4134-1-stefanha@redhat.com> References: <20190621094005.4134-1-stefanha@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 [10.5.110.46]); Fri, 21 Jun 2019 09:40:27 +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 1/4] libvhost-user: add vmsg_set_reply_u64() helper 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: "Michael S. Tsirkin" , "Dr. David Alan Gilbert" , Sebastien Boeuf , Gerd Hoffmann , Stefan Hajnoczi , =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" The VhostUserMsg request is reused as the reply by message processing functions. This is risky since request fields may corrupt the reply if the vhost-user message handler function forgets to re-initialize them. Changing this practice would be very invasive but we can introduce a helper function to make u64 payload replies safe. This also eliminates code duplication in message processing functions. Signed-off-by: Stefan Hajnoczi --- contrib/libvhost-user/libvhost-user.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-use= r/libvhost-user.c index 443b7e08c3..a8657c7af2 100644 --- a/contrib/libvhost-user/libvhost-user.c +++ b/contrib/libvhost-user/libvhost-user.c @@ -216,6 +216,15 @@ vmsg_close_fds(VhostUserMsg *vmsg) } } =20 +/* Set reply payload.u64 and clear request flags and fd_num */ +static void vmsg_set_reply_u64(VhostUserMsg *vmsg, uint64_t val) +{ + vmsg->flags =3D 0; /* defaults will be set by vu_send_reply() */ + vmsg->size =3D sizeof(vmsg->payload.u64); + vmsg->payload.u64 =3D val; + vmsg->fd_num =3D 0; +} + /* A test to see if we have userfault available */ static bool have_userfault(void) @@ -1168,10 +1177,7 @@ vu_get_protocol_features_exec(VuDev *dev, VhostUse= rMsg *vmsg) features |=3D dev->iface->get_protocol_features(dev); } =20 - vmsg->payload.u64 =3D features; - vmsg->size =3D sizeof(vmsg->payload.u64); - vmsg->fd_num =3D 0; - + vmsg_set_reply_u64(vmsg, features); return true; } =20 @@ -1307,17 +1313,14 @@ out: static bool vu_set_postcopy_listen(VuDev *dev, VhostUserMsg *vmsg) { - vmsg->payload.u64 =3D -1; - vmsg->size =3D sizeof(vmsg->payload.u64); - if (dev->nregions) { vu_panic(dev, "Regions already registered at postcopy-listen"); + vmsg_set_reply_u64(vmsg, -1); return true; } dev->postcopy_listening =3D true; =20 - vmsg->flags =3D VHOST_USER_VERSION | VHOST_USER_REPLY_MASK; - vmsg->payload.u64 =3D 0; /* Success */ + vmsg_set_reply_u64(vmsg, 0); return true; } =20 @@ -1332,10 +1335,7 @@ vu_set_postcopy_end(VuDev *dev, VhostUserMsg *vmsg= ) DPRINT("%s: Done close\n", __func__); } =20 - vmsg->fd_num =3D 0; - vmsg->payload.u64 =3D 0; - vmsg->size =3D sizeof(vmsg->payload.u64); - vmsg->flags =3D VHOST_USER_VERSION | VHOST_USER_REPLY_MASK; + vmsg_set_reply_u64(vmsg, 0); DPRINT("%s: exit\n", __func__); return true; } --=20 2.21.0