Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758201AbYBEQAv (ORCPT ); Tue, 5 Feb 2008 11:00:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753711AbYBEQAB (ORCPT ); Tue, 5 Feb 2008 11:00:01 -0500 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:54326 "EHLO amd.ucw.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751635AbYBEP77 (ORCPT ); Tue, 5 Feb 2008 10:59:59 -0500 Date: Tue, 5 Feb 2008 16:59:59 +0100 From: Pavel Machek To: Ingo Molnar Cc: Arjan van de Ven , Hugh Dickins , Jiri Kosina , kernel list , Abel Bernabeu Subject: Re: brk randomization breaks columns Message-ID: <20080205155959.GC24331@elf.ucw.cz> References: <20080204122837.GA1647@elf.ucw.cz> <20080205070001.7bc8058f@laptopd505.fenrus.org> <20080205154648.GA24331@elf.ucw.cz> <20080205154953.GA26829@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080205154953.GA26829@elte.hu> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2009 Lines: 61 On Tue 2008-02-05 16:49:53, Ingo Molnar wrote: > > * Pavel Machek wrote: > > > Hi! > > > > > > In my usual dither, I'm rather hoping Arjan will have a clear answer. > > > > > > > > > setarch works. If the apps come in source form they need fixing anyway (since I'd not be > > > surprised of current gcc reorders variables), if not.. we only have 2 cases, > > > the other case was the build process of emacs (which got fixed 5 > > > years ago). > > > > uemacs ... broken with randomization > > colums, sss ... local programs, broken with randomization > > procinfo ... broken, randomization makes it die sooner. > > mikmod ... broken with randomization > > bsdsed ... broken with randomization > > ... > > Should I test few more? > > just a quick debug question: do they all work if you start them via > setarch? I was actually toggling randomization with echo 0|1 > /proc/sys/kernel/randomize_va_space . Yes, setarch i386 -R /usr/local/bin/uemacs (etc) fixes them, too. What about this? Heap randomization breaks /lib/libc.so.5.4.33, make it possible to randomize normal stuff but leave the heap alone. Signed-off-by: Pavel Machek diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index 18ed6dd..4b099ea 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -1077,7 +1077,7 @@ #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGE current->mm->start_stack = bprm->p; #ifdef arch_randomize_brk - if (current->flags & PF_RANDOMIZE) + if ((current->flags & PF_RANDOMIZE) && (randomize_va_space > 1)) current->mm->brk = current->mm->start_brk = arch_randomize_brk(current->mm); #endif -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/