From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263928AbUD0JFX (ORCPT ); Tue, 27 Apr 2004 05:05:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263941AbUD0JFW (ORCPT ); Tue, 27 Apr 2004 05:05:22 -0400 Received: from mail1.kontent.de ([81.88.34.36]:30147 "EHLO Mail1.KONTENT.De") by vger.kernel.org with ESMTP id S263928AbUD0JFG (ORCPT ); Tue, 27 Apr 2004 05:05:06 -0400 From: Oliver Neukum To: Greg KH Subject: Re: Kernel Oops during usb usage (2.6.5) Date: Tue, 27 Apr 2004 11:04:59 +0200 User-Agent: KMail/1.5.1 Cc: Bill Davidsen , "E. Oltmanns" , linux-kernel@vger.kernel.org References: <20040423205617.GA1798@local> <200404270017.34478.oliver@neukum.org> <20040426223101.GA9258@kroah.com> In-Reply-To: <20040426223101.GA9258@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200404271104.59934.oliver@neukum.org> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Am Dienstag, 27. April 2004 00:31 schrieb Greg KH: > On Tue, Apr 27, 2004 at 12:17:34AM +0200, Oliver Neukum wrote: > > Am Montag, 26. April 2004 21:53 schrieb Greg KH: > > > On Mon, Apr 26, 2004 at 01:06:15PM -0400, Bill Davidsen wrote: > > > > Just in general, if there is anything a non-root user can do to crash > > > > the system, it's probably a kernel bug by definition. It doesn't > > > > matter that's it a stupid thing to do, it might be malicious. And in > > > > this case it might just be user error. > > > > > > But you either have to be root in order to talk to usbfs, or you were > > > root when you gave a user access to the usbfs node. So either way, a > > > "normal" user can't even do this. > > > > Greg, > > > > that's not an answer. It in effect means that usbfs is useless. > > Heh. So the correct answer is: > - don't do that. Talking to the same device through usbfs at > the same time by multiple programs is cause for lots of bad > things to happen to your device, and might possibly cause it > to hang. If you want to allow a user to access a device > through usbfs, make sure you trust them. > > Better? :) But that's not the issue, he got an oops. No, don't do that means: Reserve usbfs to root. Crashing a device which access is given to is maybe acceptable. Anything more clearly is not. Regards Oliver