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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=no 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 32C92C3A59E for ; Wed, 21 Aug 2019 22:41:56 +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 0181820856 for ; Wed, 21 Aug 2019 22:41:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0181820856 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]:36648 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i0ZIg-0006my-VZ for qemu-devel@archiver.kernel.org; Wed, 21 Aug 2019 18:41:54 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42489) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1i0ZHr-0005a2-Ts for qemu-devel@nongnu.org; Wed, 21 Aug 2019 18:41:04 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1i0ZHr-0000mg-3G for qemu-devel@nongnu.org; Wed, 21 Aug 2019 18:41:03 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50620) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1i0ZHo-0000lE-Vb; Wed, 21 Aug 2019 18:41:01 -0400 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 mx1.redhat.com (Postfix) with ESMTPS id EF43B308A958; Wed, 21 Aug 2019 22:40:59 +0000 (UTC) Received: from maximlenovopc.usersys.redhat.com (unknown [10.35.206.29]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8F7DD60126; Wed, 21 Aug 2019 22:40:55 +0000 (UTC) Message-ID: <41fe8d6996e41ad987bef3ba397e6f0c6fe7b056.camel@redhat.com> From: Maxim Levitsky To: Max Reitz , qemu-devel@nongnu.org Date: Thu, 22 Aug 2019 01:40:54 +0300 In-Reply-To: <6019b9e3-a4a6-4780-9652-f7c2bec024a5@redhat.com> References: <20190814202219.1870-1-mlevitsk@redhat.com> <20190814202219.1870-6-mlevitsk@redhat.com> <6019b9e3-a4a6-4780-9652-f7c2bec024a5@redhat.com> Content-Type: text/plain; charset="UTF-8" Mime-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.41]); Wed, 21 Aug 2019 22:41:00 +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: Re: [Qemu-devel] [PATCH 05/13] qcrypto-luks: clear the masterkey and password before freeing them always 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 , Fam Zheng , "Daniel P. =?ISO-8859-1?Q?Berrang=E9?=" , qemu-block@nongnu.org, Markus Armbruster , Stefan Hajnoczi Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, 2019-08-20 at 20:12 +0200, Max Reitz wrote: > On 14.08.19 22:22, Maxim Levitsky wrote: > > While there are other places where these are still stored in memory, > > this is still one less key material area that can be sniffed with > > various side channel attacks > >=20 > >=20 > >=20 >=20 > (Many empty lines here) >=20 > > Signed-off-by: Maxim Levitsky > > --- > > crypto/block-luks.c | 52 ++++++++++++++++++++++++++++++++++++++-----= -- > > 1 file changed, 44 insertions(+), 8 deletions(-) >=20 > Wouldn=E2=80=99t it make sense to introduce a dedicated function for th= is? Absolutely. I was mostly focused on fixing all the cases first. I usually refactor such ugly code at the end, but this time I forgot to do so. Plus I need to pick a place where to put such function (it can be useful = in any place in qemu),=20 and first check if maybe glib already has such free+scrub function implem= ented somewhere. Best regards, Maxim Levitsky