From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752247Ab3KKCW7 (ORCPT ); Sun, 10 Nov 2013 21:22:59 -0500 Received: from terminus.zytor.com ([198.137.202.10]:35458 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751016Ab3KKCWu (ORCPT ); Sun, 10 Nov 2013 21:22:50 -0500 Message-ID: <52803F15.3080204@zytor.com> Date: Sun, 10 Nov 2013 18:21:09 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0 MIME-Version: 1.0 To: Dave Young CC: Matt Fleming , linux-kernel@vger.kernel.org, linux-efi@vger.kernel.org, x86@kernel.org, mjg59@srcf.ucam.org, James.Bottomley@HansenPartnership.com, vgoyal@redhat.com, ebiederm@xmission.com, horms@verge.net.au, kexec@lists.infradead.org, bp@alien8.de, Greg KH Subject: Re: [patch 0/7 v2] kexec kernel efi runtime support References: <20131105082007.872550445@dhcp-16-126.nay.redhat.com> <20131108143118.GA22636@console-pimps.org> <20131109035739.GB4294@dhcp-16-126.nay.redhat.com> <527DC1BE.6030107@zytor.com> <20131111021356.GC4407@dhcp-16-126.nay.redhat.com> In-Reply-To: <20131111021356.GC4407@dhcp-16-126.nay.redhat.com> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/10/2013 06:13 PM, Dave Young wrote: > > Huang Ying created the debugfs file for boot_params. > His first version patch tried sysfs, but sysfs is not designed for such > binary blobs so finally it go to debugfs. > That is a misunderstanding. Binary blobs can exist in sysfs as long as the blob is something that is inherently a blob. This is admittedly a corner case, but it is without any doubt a protocol-defined binary structure. The reason it was put in debugfs is that there was no non-debug user for it at the time. > Any idea for this is welcome, till now I have no better idea for such kind > of data. We should have another *fs instead of using debugfs. The problem with debugfs is that things go into debugfs with largely no auditing. As a result, mounting debugfs is very likely to mean that your system is exploitable one way or another. -hpa