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=-15.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 C92C4C433ED for ; Fri, 14 May 2021 12:12:50 +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 5FFDF6143D for ; Fri, 14 May 2021 12:12:50 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5FFDF6143D 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]:60506 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lhWgT-0004r8-Ck for qemu-devel@archiver.kernel.org; Fri, 14 May 2021 08:12:49 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:54136) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lhWZZ-0007p3-Nt for qemu-devel@nongnu.org; Fri, 14 May 2021 08:05:41 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:34073) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lhWZX-00071S-TH for qemu-devel@nongnu.org; Fri, 14 May 2021 08:05:41 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1620993939; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=10f3OOVF2aB5XyPgGrypM2mVeITqE55I760zVMyuWOU=; b=cZF9EHYbpur4zUlEIo5IBccHzU2vHizV0svkK0o61gk8Oz/CKNV7NJSkn+PeCQ8OrgXUcW QpzZsHx03rn3xabUwnNYZwDAhd0uoCCiifh32+e+DEMeE1HfBBQTsJrQbcv0JAYA6pKC2Y /5Cs2CrLM6Iaiy7LGlxlpTKUO5umAJk= 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-62-LVu__YJFN-6F7f9aqvh5lg-1; Fri, 14 May 2021 08:05:34 -0400 X-MC-Unique: LVu__YJFN-6F7f9aqvh5lg-1 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 mimecast-mx01.redhat.com (Postfix) with ESMTPS id 97B98805EF2 for ; Fri, 14 May 2021 12:05:33 +0000 (UTC) Received: from redhat.com (ovpn-113-212.ams2.redhat.com [10.36.113.212]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 55A575F9B8; Fri, 14 May 2021 12:05:32 +0000 (UTC) Date: Fri, 14 May 2021 13:05:29 +0100 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= Subject: Re: [PATCH v2 1/2] net/tap: fix FreeBSD portability problem receiving TAP FD Message-ID: References: <20210512153654.1178035-1-berrange@redhat.com> <20210512153654.1178035-2-berrange@redhat.com> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/2.0.6 (2021-03-06) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=170.10.133.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -34 X-Spam_score: -3.5 X-Spam_bar: --- X-Spam_report: (-3.5 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.699, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: Connor Kuehl , Jason Wang , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, May 12, 2021 at 06:35:57PM +0200, Philippe Mathieu-Daudé wrote: > On 5/12/21 5:36 PM, Daniel P. Berrangé wrote: > > The CMSG_LEN and CMSG_SPACE macros must not be assumed to return the > > same value. The msg_controllen field must be initialized using > > CMSG_SPACE when using SCM_RIGHTS. > > > > This ought to fix any FD receive issues users might be hitting on > > 64-bit FeeBSD / NetBSD platforms. The flaw was noticed first in > > GNULIB > > > > https://lists.gnu.org/archive/html/bug-gnulib/2021-02/msg00066.html > > > > and QEMU's code has the same logic bug. > > > > Reviewed-by: Connor Kuehl > > Signed-off-by: Daniel P. Berrangé > > --- > > net/tap.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/net/tap.c b/net/tap.c > > index bae895e287..276a9077fc 100644 > > --- a/net/tap.c > > +++ b/net/tap.c > > @@ -467,7 +467,7 @@ static int recv_fd(int c) > > cmsg->cmsg_level = SOL_SOCKET; > > cmsg->cmsg_type = SCM_RIGHTS; > > cmsg->cmsg_len = CMSG_LEN(sizeof(fd)); > > - msg.msg_controllen = cmsg->cmsg_len; > > + msg.msg_controllen = CMSG_SPACE(sizeof(fd)); > > > > iov.iov_base = req; > > iov.iov_len = sizeof(req); > > > > Possibly more: Ewwwww, yes :-( Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|