Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754850AbZG1QX4 (ORCPT ); Tue, 28 Jul 2009 12:23:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754841AbZG1QXz (ORCPT ); Tue, 28 Jul 2009 12:23:55 -0400 Received: from one.firstfloor.org ([213.235.205.2]:59348 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754831AbZG1QXz (ORCPT ); Tue, 28 Jul 2009 12:23:55 -0400 Date: Tue, 28 Jul 2009 18:23:53 +0200 From: Andi Kleen To: Kees Cook Cc: Andi Kleen , Alan Cox , James Morris , James Carter , Eric Paris , linux-kernel@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@tycho.nsa.gov, Stephen Smalley , spender@grsecurity.net, Daniel J Walsh , cl@linux-foundation.org, Arjan van de Ven , Chad Sellers , Tetsuo Handa , mingo@elte.hu Subject: Re: mmap_min_addr and your local LSM (ok, just SELinux) Message-ID: <20090728162353.GO15310@basil.fritz.box> References: <1248132223.2654.278.camel@localhost> <1248187482.19456.90.camel@moss-lions.epoch.ncsc.mil> <20090728011943.589176cb@lxorguk.ukuu.org.uk> <87zlapgo2u.fsf@basil.nowhere.org> <20090728155622.GO7316@outflux.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090728155622.GO7316@outflux.net> 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: 707 Lines: 16 > Could the page table flags be used to mask this region? i.e. force > PROT_NONE (with the "desired" flags stored elsewhere) and in the segv > handler check if it is kernel or user space, and then fix-up the flags and > continue if it's userspace? (I really don't know the internals on this, > but it would need to restore PROT_NONE on task-switch or something...) That's racy with multiple threads. -Andi -- ak@linux.intel.com -- Speaking for myself only. -- 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/