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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 BAF34C6778A for ; Tue, 24 Jul 2018 12:55:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4D1B420856 for ; Tue, 24 Jul 2018 12:55:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4D1B420856 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388589AbeGXOB6 (ORCPT ); Tue, 24 Jul 2018 10:01:58 -0400 Received: from mx2.suse.de ([195.135.220.15]:51870 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2388322AbeGXOB5 (ORCPT ); Tue, 24 Jul 2018 10:01:57 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay1.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id A107FAD94; Tue, 24 Jul 2018 12:55:33 +0000 (UTC) Message-ID: <1532436474.17797.20.camel@suse.com> Subject: Re: [PATCH 0/4][RFC v2] Introduce the in-kernel hibernation encryption From: Oliver Neukum To: Pavel Machek , Yu Chen Cc: "Rafael J . Wysocki" , Eric Biggers , "Lee, Chun-Yi" , Theodore Ts o , Stephan Mueller , Denis Kenzior , linux-pm@vger.kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, "Gu, Kookoo" , "Zhang, Rui" Date: Tue, 24 Jul 2018 14:47:54 +0200 In-Reply-To: <20180724120133.GD26036@amd> References: <20180718202235.GA4132@amd> <20180718235851.GA22170@sandybridge-desktop> <20180719110149.GA4679@amd> <20180719132003.GA30981@sandybridge-desktop> <20180720102532.GA20284@amd> <1532346156.3057.11.camel@suse.com> <20180723162302.GA4503@sandybridge-desktop> <20180724120133.GD26036@amd> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.26.6 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Di, 2018-07-24 at 14:01 +0200, Pavel Machek wrote: > Hi! > > > > > > "There have some functions be locked-down because > > > > > there have no appropriate mechanisms to check the > > > > > integrity of writing data." > > > > > https://patchwork.kernel.org/patch/10476751/ > > > > > > > > So your goal is to make hibernation compatible with kernel > > > > lockdown? Do your patches provide sufficient security that hibernation > > > > can be enabled with kernel lockdown? > > > > > > OK, maybe I am dense, but if the key comes from user space, will that > > > be enough? > > > > > > > Good point, we once tried to generate key in kernel, but people > > suggest to generate key in userspace and provide it to the > > kernel, which is what ecryptfs do currently, so it seems this > > should also be safe for encryption in kernel. > > Safe against what kind of attack? Please describe what kind of > security you are trying to provide. Unsigned code must not take over the priviledge level of signed code. Hence: 1. Unsigned code must not allowed to read sensitive parts of signed code's memory space 2. Unsigned code must not be able to alter the memory space of signed code -> snapshots that are changed must not be able to be resumed > I don't think generating key in userspace is good enough for providing > guarantees for secure-boot. Why? Regards Oliver