From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754285AbaFJVkx (ORCPT ); Tue, 10 Jun 2014 17:40:53 -0400 Received: from mail-wg0-f46.google.com ([74.125.82.46]:38727 "EHLO mail-wg0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753874AbaFJVkt (ORCPT ); Tue, 10 Jun 2014 17:40:49 -0400 MIME-Version: 1.0 In-Reply-To: References: <1402331614.7064.60.camel@dhcp-9-2-203-236.watson.ibm.com> <20140610122008.GA31944@hansolo.jdub.homelinux.org> <20140610204021.GA8916@srcf.ucam.org> <20140610212516.GB10614@srcf.ucam.org> Date: Wed, 11 Jun 2014 00:40:48 +0300 Message-ID: Subject: Re: [PATCH 0/4] KEYS: validate key trust with owner and builtin keys only From: Dmitry Kasatkin To: Matthew Garrett Cc: Josh Boyer , David Howells , Mimi Zohar , Dmitry Kasatkin , keyrings , "linux-kernel@vger.kernel.org" , linux-security-module Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11 June 2014 00:34, Dmitry Kasatkin wrote: > On 11 June 2014 00:25, Matthew Garrett wrote: >> On Wed, Jun 11, 2014 at 12:17:53AM +0300, Dmitry Kasatkin wrote: >> >>> It is probably just a paranoia... >>> Kconfig MODULE_SIG_UEFI should tell about threat of loading kernel >>> modules from NSA or Lenovo signed by MS or Lenovo keys.. >>> >>> This hole is opened without warning... >> >> It's not typically a hole. If an attacker has root they can just replace >> your bootloader with one signed by a trusted key and then have that >> modify the kernel before booting it. >> >> If you're using a TPM then you can mitigate this, but if you have a TPM >> then you're already performing some extra steps during the boot process. >> Just add a sysfs knob that lets you drop the db keys and incorporate >> that into the TPM management code. >> >> -- >> Matthew Garrett | mjg59@srcf.ucam.org > > I was expecting this boot loader answer. > > Indeed, if system is design to prevent online modification of bootloader then > kernel parameters are protected as well... > > My statement is still valid. It is a hole... > > To prevent the hole it should be explained that one might follow > certain instructions > to take ownership of your PC. Generate your own keys and remove MS and > Vendor ones... > > It is paranoia? May be not. > > - Dmitry I must admit that bootloader replacement is not related to kernel... It is just paranoia... - dmitry