From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga09.intel.com ([134.134.136.24]:58306 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932141AbdJZLBU (ORCPT ); Thu, 26 Oct 2017 07:01:20 -0400 Date: Thu, 26 Oct 2017 13:01:15 +0200 From: Jarkko Sakkinen To: Matthew Garrett , linux-integrity , Kari Hiitola , linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, Alexander Steffen Subject: Re: Fixing CVE-2017-15361 Message-ID: <20171026110115.lyubl22zikwlulhi@linux.intel.com> References: <20171025134438.vgh6tzkups2tujps@linux.intel.com> <20171025185349.ocptudim3g35j6im@linux.intel.com> <20171025202221.gkgch7rjjqoblzpf@rhwork> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20171025202221.gkgch7rjjqoblzpf@rhwork> Sender: linux-integrity-owner@vger.kernel.org List-ID: On Wed, Oct 25, 2017 at 01:22:21PM -0700, Jerry Snitselaar wrote: > On Wed Oct 25 17, Jarkko Sakkinen wrote: > > On Wed, Oct 25, 2017 at 07:17:17AM -0700, Matthew Garrett wrote: > > > On Wed, Oct 25, 2017 at 6:44 AM, Jarkko Sakkinen > > > wrote: > > > > I'm implementing a fix for CVE-2017-15361 that simply blacklists > > > > vulnerable FW versions. I think this is the only responsible action from > > > > my side that I can do. > > > > > > I'm not sure this is ideal - do Infineon have any Linux tooling for > > > performing firmware updates, and if so will that continue working if > > > the device is blacklisted? It's also a poor user experience to have > > > systems using TPM-backed disk encryption keys suddenly rendered > > > unbootable, and making it as easy as possible for people to do an > > > upgrade and then re-seal secrets with new keys feels like the correct > > > approach. > > > > I talked today with Alexander Steffen in the KS unconference and we > > concluded that this would be a terrible idea. > > > > Alexander stated the following things about FW updates (Alexander, > > please correct me if I state something incorrectly or if you have > > something to add): > > > > * FW update can be constructed either in a way that the keys in the > > NVRAM are not cleared or in a way that they are cleared. > > * FW update cannot be directly applied to the TPM but must come as > > part of the firmware update from the vendor. > > If that is the case, can the two of you get Intel to update the fw > for the tpm in the nuc5i5myhe (slb9665) :) ? It has needed an update for a while, due > to issues with context management. My understanding (quite likely I misunderstood) > from a recent discussion with Peter was that it was possible to update the fw. I don't know but I can at least forward the complains to the mother ship :-) It is fairly intuitive why dTPM cannot be updated without full firmware update. It's part of the proprietary HW platform, not something connected through PCI, USB or any standard bus. /Jarkko