From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758016AbYENFqu (ORCPT ); Wed, 14 May 2008 01:46:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752483AbYENFql (ORCPT ); Wed, 14 May 2008 01:46:41 -0400 Received: from 1wt.eu ([62.212.114.60]:4309 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752291AbYENFqj (ORCPT ); Wed, 14 May 2008 01:46:39 -0400 Date: Wed, 14 May 2008 07:46:34 +0200 From: Willy Tarreau To: Harald Dunkel Cc: Vegard Nossum , linux-kernel@vger.kernel.org Subject: Re: 2.6.25.3: su gets stuck for root Message-ID: <20080514054634.GA2645@1wt.eu> References: <4829326A.6060808@t-online.de> <19f34abd0805122347x4d9c5d03m16679d724189790e@mail.gmail.com> <4829D345.7020909@t-online.de> <20080513194612.GV8474@1wt.eu> <482A70BC.3010607@t-online.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <482A70BC.3010607@t-online.de> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, May 14, 2008 at 06:55:24AM +0200, Harald Dunkel wrote: > Willy Tarreau wrote: > > > >even as root ? Because if you run strace on "su" as a user, you will > >lose the setuid which may change the conditions. > > > > It gets stuck _only_ if I am root. Running su without root permission > is no problem. OK. That's quite strange. > As written before, If I kick out the "stty intr '^C'" from root's > .bashrc, then the second su succeeds. Running the stty command > manually in this new shell is no problem. > > Can you reproduce this problem? It doesn't need XWindow or any > special user. Simply login as root on tty2, and run "su". If it > gets stuck, then you could login on tty3 and kill -9 ### the blocking > stty. I tried (I'm on 2.6.25.1). But neither "su", "su willy" nor "stty intr ^C" caused such a problem unfortunately. You may want to ask several people to test in the same environment as yours (same distro, etc...) in order to find whether it's a user-land bug or a kernel bug. Most likely it's a kernel bug or side effect which is triggered by your version of su or stty. > Regards > > Harri Willy