From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S270851AbTGPOIT (ORCPT ); Wed, 16 Jul 2003 10:08:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S270852AbTGPOIR (ORCPT ); Wed, 16 Jul 2003 10:08:17 -0400 Received: from dsl093-172-017.pit1.dsl.speakeasy.net ([66.93.172.17]:52883 "EHLO nevyn.them.org") by vger.kernel.org with ESMTP id S270851AbTGPOH5 (ORCPT ); Wed, 16 Jul 2003 10:07:57 -0400 Date: Wed, 16 Jul 2003 10:22:49 -0400 From: Daniel Jacobowitz To: Linux kernel Subject: Re: SUID root Message-ID: <20030716142249.GA22473@nevyn.them.org> Mail-Followup-To: Linux kernel References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org 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. -- Daniel Jacobowitz MontaVista Software Debian GNU/Linux Developer