From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757328AbXH0Pey (ORCPT ); Mon, 27 Aug 2007 11:34:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755924AbXH0Per (ORCPT ); Mon, 27 Aug 2007 11:34:47 -0400 Received: from mail.gmx.net ([213.165.64.20]:37575 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1755812AbXH0Peq (ORCPT ); Mon, 27 Aug 2007 11:34:46 -0400 X-Authenticated: #24879014 X-Provags-ID: V01U2FsdGVkX199agsiA+F9Xv1YWqIe5xTcvbgSKzj216f5yHBzfu 87DrzMLRhztwuA Message-ID: <46D2EEA2.6070501@gmx.net> Date: Mon, 27 Aug 2007 17:32:50 +0200 From: Michael Kerrisk User-Agent: Thunderbird 1.5.0.8 (X11/20060911) MIME-Version: 1.0 To: Marcel Holtmann CC: Linus Torvalds , linux-kernel@vger.kernel.org Subject: Re: [PATCH] Reset current->pdeath_signal on SUID binary execution References: <1187380078.6698.448.camel@violet> <1187857271.15402.20.camel@violet> In-Reply-To: <1187857271.15402.20.camel@violet> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Y-GMX-Trusted: 0 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Marcel, >> the attached patch fixes a flaw in the "parent process death signal" >> when executing SUID binaries. An unprivileged user may send arbitrary >> signal to a child process even if it is running with higher privileges. >> >> The idea to fix this issue is to reset pdeath_signal not only on fork, >> but also on the execution of a SUID binary. >> >> Michael, if we fix it this way, then the prctl() manual page should >> reflect that behavior. > > the patch has been merged into 2.4 and 2.6, so the manual page needs an > update at some point. I see your patch at: http://article.gmane.org/gmane.linux.kernel/571635/match=pdeath%5fsignal+suid+binary+execution But it's not clear to me in which 2.4.x and 2.6.x versions the change occurred (it isn't in 2.6.23-rc3 -- is it scheduled for 2.6.23-rc4?). Can you enlighten me? Cheers, Michael >> From comments it seems that we have to also reset pdeath_signal inside >> LSM when it comes to capability-raised executes, but I must admit that I >> got lost there. > > No further comments for this one? I am not familiar enough with it. > > Regards > > Marcel > > -- Michael Kerrisk maintainer of Linux man pages Sections 2, 3, 4, 5, and 7 Want to help with man page maintenance? Grab the latest tarball at http://www.kernel.org/pub/linux/docs/manpages/ read the HOWTOHELP file and grep the source files for 'FIXME'.