From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964801Ab2AEQln (ORCPT ); Thu, 5 Jan 2012 11:41:43 -0500 Received: from mx1.redhat.com ([209.132.183.28]:1032 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932711Ab2AEQlm (ORCPT ); Thu, 5 Jan 2012 11:41:42 -0500 Message-ID: <4F05D286.7030205@redhat.com> Date: Thu, 05 Jan 2012 17:40:38 +0100 From: Paolo Bonzini User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:9.0) Gecko/20111222 Thunderbird/9.0 MIME-Version: 1.0 To: Linus Torvalds CC: Willy Tarreau , linux-kernel@vger.kernel.org, security@kernel.org, pmatouse@redhat.com, agk@redhat.com, jbottomley@parallels.com, mchristi@redhat.com, msnitzer@redhat.com, Christoph Hellwig Subject: Re: [PATCH 2/3] block: fail SCSI passthrough ioctls on partition devices References: <1324576939-23619-3-git-send-email-pbonzini@redhat.com> <4EF38269.7080804@redhat.com> <4EF391A6.2040504@redhat.com> <4EF3AA74.1060801@redhat.com> <20111222234830.GC31021@agk-dp.fab.redhat.com> <20111223062649.GD21994@1wt.eu> <4EF48CE4.3000104@redhat.com> <4F05A332.1060600@redhat.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/05/2012 05:16 PM, Linus Torvalds wrote: > On Thu, Jan 5, 2012 at 5:18 AM, Paolo Bonzini wrote: >> >> Hence, changing scsi_verify_blk_ioctl to return ENOIOCTLCMD is not >> really possible. > > What? > > "We have a bug in the block IO layer, so we cannot possible fix > another problem?" > > Whjat the f*ck is the logic there? > > Just fix the *obvious* breakage in BLKROSET. It's clearly what the > code *intends* to do, it just didn't check for ENOIOCTLCMD. Aha, so this is clear and obvious. And who knows that something else won't break? Such as the 32-on-64 logic that already uses ENOIOCTLCMD for something else? If the block maintainers want to fix that, fine. "git blame block/ioctl.c" shows that it's been like this for 6 years and in general the file has hardly seen changes. That's enough to make me steer away from that code. Foolish me who found a bug, and an exploitable one for that matter, and even tried to fix it. Looks like security by obscurity would have served users better. Paolo