From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964847AbWC1Xtw (ORCPT ); Tue, 28 Mar 2006 18:49:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964849AbWC1Xtw (ORCPT ); Tue, 28 Mar 2006 18:49:52 -0500 Received: from main.gmane.org ([80.91.229.2]:25049 "EHLO ciao.gmane.org") by vger.kernel.org with ESMTP id S964847AbWC1Xtv (ORCPT ); Tue, 28 Mar 2006 18:49:51 -0500 X-Injected-Via-Gmane: http://gmane.org/ To: linux-kernel@vger.kernel.org From: =?iso-8859-1?Q?M=E5ns_Rullg=E5rd?= Subject: Re: Who wants to test cracklinux?? Date: Wed, 29 Mar 2006 00:49:43 +0100 Message-ID: References: <20060328221223.80753cab.letterdrop@gmx.de> <20060328224929.GC5760@elf.ucw.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Complaints-To: usenet@sea.gmane.org X-Gmane-NNTP-Posting-Host: 82.153.166.94 User-Agent: Gnus/5.1007 (Gnus v5.10.7) XEmacs/21.4.15 (Security Through Obscurity, linux) Cancel-Lock: sha1:KTEiJfVGXq77j4wQrEkmvwJAYNc= Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Pavel Machek writes: > Hi! > >> I've written a small kernel module & shared object for kernel 2.6 to >> enable the following for normal users: >> >> - inb()/outb()... via a wrapper function > > ioperm() does that already, no? You mean, you enable it for non-root, > too? That's security hole. > >> - enable direct IO access (like ioperm()) >> - direct access on physical memory addresses > > read/write on /dev/mem. chmod 666 /dev/mem if you want to allow normal > users to access physical memory (security hole, again). It's a security risk, but one that you might sometimes take to gain some performance on a non-critical machine. I've done this in the past to be able to play videos smoothly on a slow machine. >> - installation of user space ISR > > That seems nice. Does it work with PCI shared interrupts? I obviously can't comment on this case, but I've successfully done it previously, so it's demonstrably possible. The code is all available from vidix.sf.net, although it's not updated to the latest ways of doing things. -- Måns Rullgård mru@inprovide.com