Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 11 Mar 2002 23:14:01 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 11 Mar 2002 23:13:51 -0500 Received: from parcelfarce.linux.theplanet.co.uk ([195.92.249.252]:51982 "EHLO www.linux.org.uk") by vger.kernel.org with ESMTP id ; Mon, 11 Mar 2002 23:13:40 -0500 Message-ID: <3C8D8061.4030503@mandrakesoft.com> Date: Mon, 11 Mar 2002 23:13:21 -0500 From: Jeff Garzik User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.8) Gecko/20020214 X-Accept-Language: en MIME-Version: 1.0 To: Olivier Galibert CC: LKML Subject: Re: [patch] My AMD IDE driver, v2.7 In-Reply-To: <3C8D69E3.3080908@mandrakesoft.com> <20020311223439.A2434@zalem.nrockv01.md.comcast.net> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Olivier Galibert wrote: >On Mon, Mar 11, 2002 at 09:37:23PM -0500, Jeff Garzik wrote: > >>It serves to encourage openness, nobody is forced to use it, and it >>provides an additional layer of protection for those that choose to use >>it. That is the point. >> > >It doesn't provide any meaningful protection, that's the point. > >If you're root/have CAP_SYS_RAWIO, you can bit-bang the interface, you >can patch out the filter from the kernel binary, you can do whatever >pleases you. Don't run evil programs as root in the first place. And >if you want to have finer-grained capabilities for specific >drive-level actions, create an higher-level interface for them which >will guarantee that only safe commands are used because they will be > Under more restricted domains, root cannot bit-bang the interface. s/CAP_SYS_RAWIO/CAP_DEVICE_CMD/ for the raw cmd ioctl interface. Have the OS trap I/O port accesses using SMM mode if you would like, and that applies to your particular security situation. The filter is useful for other reasons like correctness, as well. Jeff - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/