Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759913AbXHORko (ORCPT ); Wed, 15 Aug 2007 13:40:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1765759AbXHORkg (ORCPT ); Wed, 15 Aug 2007 13:40:36 -0400 Received: from mx1.redhat.com ([66.187.233.31]:39673 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760750AbXHORkf (ORCPT ); Wed, 15 Aug 2007 13:40:35 -0400 Message-ID: <46C33A67.1020102@redhat.com> Date: Wed, 15 Aug 2007 13:39:51 -0400 From: Chuck Ebbert Organization: Red Hat User-Agent: Thunderbird 1.5.0.12 (X11/20070719) MIME-Version: 1.0 To: Jiri Kosina CC: Jakub Jelinek , Andrew Morton , Ingo Molnar , Roland McGrath , "H. Peter Anvin" , Ulrich Kunitz , Bret Towe , linux-kernel@vger.kernel.org, Arjan van de Ven Subject: Re: [PATCH] [RESEND] PIE executable randomization References: <20070814200647.GN2063@devserv.devel.redhat.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1260 Lines: 30 On 08/14/2007 04:41 PM, Jiri Kosina wrote: > (added Arjan to CC, as he has been working on the kernel part of the > randomization previously) > > On Tue, 14 Aug 2007, Jakub Jelinek wrote: > >> If I'm reading the above hunk correctly, this means we will randomize >> all PIEs and even all dynamic linkers invoked as executables on i?86 and >> x86_64, and on the rest of arches we won't randomize at all, instead >> load ET_DYN objects at ELF_ET_DYN_BASE address. But I don't see anything >> i?86/x86_64 specific on this. > > Hi Jakub, > > actually, it is currently arch-specific, and that's because of different > memory layouts on different archs. > > It turned out recently that PIE-compiled binaries on x86_64, that perform > larger amount of brk-allocations (for example bash) will not work (but > they will work on ?86). This is because currently on ?86 the memory layout > is as follows: But your patch is enabling randomization for x86_64, because CONFIG_X86 includes both 32 and 64 bit archs. - 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/