From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S270863AbTGPOZO (ORCPT ); Wed, 16 Jul 2003 10:25:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270872AbTGPOZO (ORCPT ); Wed, 16 Jul 2003 10:25:14 -0400 Received: from chaos.analogic.com ([204.178.40.224]:3206 "EHLO chaos.analogic.com") by vger.kernel.org with ESMTP id S270863AbTGPOZJ (ORCPT ); Wed, 16 Jul 2003 10:25:09 -0400 Date: Wed, 16 Jul 2003 10:42:03 -0400 (EDT) From: "Richard B. Johnson" X-X-Sender: root@chaos Reply-To: root@chaos.analogic.com To: Daniel Jacobowitz cc: Linux kernel Subject: Re: SUID root In-Reply-To: <20030716142249.GA22473@nevyn.them.org> Message-ID: References: <20030716142249.GA22473@nevyn.them.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 16 Jul 2003, Daniel Jacobowitz wrote: > On Wed, Jul 16, 2003 at 10:19:14AM -0400, Richard B. Johnson wrote: > > > > It appears as though SUID root programs don't work on > > linux 2.4.20, 2.4.21, or 2.4.22-pre6, or at least what > > used to work no longer does. > > > > One program tries to execute iopl(3). In the event that > > it fails, it tries to set UID/GID to root after saving > > the previous, then tries again. > > > > The program exists in /usr/bin, properly owned by root. It > > is set SUID, 4755, and otherwise works. Anybody have any > > clues? Do SUID programs have to be re-written to use some > > other mechanism? I need to have a user-mode program get > > access to an otherwise unused printer port. It's a shame > > to write a module just for this. > > You're stracing it. Stracing prevents setuid from occurring; it used > to just prevent the exec. > Okay. Thanks, you are right. It is actually working I guess. Cheers, Dick Johnson Penguin : Linux version 2.4.20 on an i686 machine (797.90 BogoMips). Note 96.3% of all statistics are fiction.