From nobody Sun Oct 5 19:27:29 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail(p=none dis=none) header.from=redhat.com ARC-Seal: i=1; a=rsa-sha256; t=1563550020; cv=none; d=zoho.com; s=zohoarc; b=KB/fSjfMyDV/I7AfF6ltwvsg/RglAXe/ShdgoNwjP+oW29wI9ueqWmf4j2UO24A/Pu1hw9CM0BUB1rjBTJCUF2oUEHZKbysGpEZP4mYcpfwWFqx+jXxpm0gRLH1fJ9hH4e95/XTa1nEimhg0hFrTfu9iUsWR5pNAIPjwz4C7zkA= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1563550020; h=Content-Transfer-Encoding:Cc:Date:From:List-Subscribe:List-Post:List-Id:List-Archive:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Sender:Subject:To:ARC-Authentication-Results; bh=jC3CiYy2X2Y4ph3q1leQvo8UM/sTsML6RMovZ+LF/TE=; b=Cvtv3owi2lu3rFsn9UaL+B3+ppQvd6DvqwNhjwoRTEvJqn4vVqfA4WckSS9E/xdWY5P4JI0EPV+CACHCpmD961Q+4OtWmkgQVv2mfKjBi7dowGIUMuHR7KW2TVFRBAovuoOh+p+hyE4zz+UY0tkaXJIkryN1ZleRZ/hD/PnSoAk= ARC-Authentication-Results: i=1; mx.zoho.com; spf=pass (zoho.com: domain of gnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org; dmarc=fail header.from= (p=none dis=none) header.from= Return-Path: Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) by mx.zohomail.com with SMTPS id 156355002089181.30246386017848; Fri, 19 Jul 2019 08:27:00 -0700 (PDT) Received: from localhost ([::1]:46258 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hoUmh-0005KE-Uq for importer@patchew.org; Fri, 19 Jul 2019 11:26:59 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60096) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hoUmY-0004vT-1b for qemu-devel@nongnu.org; Fri, 19 Jul 2019 11:26:51 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hoUmU-0004Vd-Bh for qemu-devel@nongnu.org; Fri, 19 Jul 2019 11:26:48 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40185) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hoUmF-0002PC-2P; Fri, 19 Jul 2019 11:26:34 -0400 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 936BE30B9912; Fri, 19 Jul 2019 15:03:19 +0000 (UTC) Received: from blue.redhat.com (ovpn-116-46.phx2.redhat.com [10.3.116.46]) by smtp.corp.redhat.com (Postfix) with ESMTP id ED3BA1001B14; Fri, 19 Jul 2019 15:03:18 +0000 (UTC) From: Eric Blake To: qemu-devel@nongnu.org Date: Fri, 19 Jul 2019 10:03:13 -0500 Message-Id: <20190719150313.29198-1-eblake@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.47]); Fri, 19 Jul 2019 15:03:19 +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] nbd: Initialize reply on failure 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: Kevin Wolf , Andrey Shinkevich , Thomas Huth , "open list:Network Block Dev..." , Max Reitz Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" Content-Type: text/plain; charset="utf-8" We've had two separate reports of a caller running into use of uninitialized data if s->quit is set (one detected by gcc -O3, another by valgrind), due to checking 'nbd_reply_is_simple(reply) || s->quit' in the wrong order. Rather than chasing down which callers need to pre-initialize reply, it's easier to guarantee that reply will always be set by nbd_co_receive_one_chunk() even on failure. Reported-by: Thomas Huth Reported-by: Andrey Shinkevich Signed-off-by: Eric Blake Reviewed-by: Andrey Shinkevich Reviewed-by: Philippe Mathieu-Daud=C3=A9 --- Replaces: https://lists.gnu.org/archive/html/qemu-devel/2019-07/msg04477.ht= ml Replaces: https://lists.gnu.org/archive/html/qemu-devel/2019-07/msg03712.ht= ml block/nbd.c | 1 + 1 file changed, 1 insertion(+) diff --git a/block/nbd.c b/block/nbd.c index 8d565cc624ec..f751a8e633e5 100644 --- a/block/nbd.c +++ b/block/nbd.c @@ -640,6 +640,7 @@ static coroutine_fn int nbd_co_receive_one_chunk( request_ret, qiov, payload, errp= ); if (ret < 0) { + memset(reply, 0, sizeof *reply); s->quit =3D true; } else { /* For assert at loop start in nbd_connection_entry */ --=20 2.20.1