Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752364AbbK2LPv (ORCPT ); Sun, 29 Nov 2015 06:15:51 -0500 Received: from r00tworld.com ([212.85.137.150]:50918 "EHLO r00tworld.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752119AbbK2LPs (ORCPT ); Sun, 29 Nov 2015 06:15:48 -0500 From: "PaX Team" To: Ingo Molnar Date: Sun, 29 Nov 2015 12:15:01 +0100 MIME-Version: 1.0 Subject: Re: [kernel-hardening] [PATCH 0/2] introduce post-init read-only memory Reply-to: pageexec@freemail.hu CC: Linus Torvalds , kernel-hardening@lists.openwall.com, Mathias Krause , "linux-kernel@vger.kernel.org" , Kees Cook , Andy Lutomirski , Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , x86-ml , Arnd Bergmann , Michael Ellerman , linux-arch@vger.kernel.org, Emese Revfy Message-ID: <565ADE35.20892.225C67C2@pageexec.freemail.hu> In-reply-to: <20151129080853.GB23721@gmail.com> References: <1448401114-24650-1-git-send-email-keescook@chromium.org>, <565876F3.21515.18F8DF8F@pageexec.freemail.hu>, <20151129080853.GB23721@gmail.com> X-mailer: Pegasus Mail for Windows (4.70) Content-type: text/plain; charset=US-ASCII Content-transfer-encoding: 7BIT Content-description: Mail message body X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-2.1.12 (r00tworld.com [212.85.137.150]); Sun, 29 Nov 2015 12:15:03 +0100 (CET) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1203 Lines: 25 On 29 Nov 2015 at 9:08, Ingo Molnar wrote: > > * PaX Team wrote: > > > i don't see the compile time vs. runtime detection as 'competing' approaches, > > both have their own role. [...] > > That's true - but only as long as 'this can be solved in tooling!' is not used as > an excuse to oppose the runtime solution and we end up doing neither. actually, i already voiced my opinion elsewhere in the constify thread on the kernel hardening list that adding/using __read_only is somewhat premature without also adding the compile time verification part (as part of the constify plugin for example). right now its use on the embedded vdso image is simple and easy to verify but once people begin to add it to variables that the compiler knows and cares about (say, the ops structures) then things can become fragile without compile checking. so yes, i'd also advise to get such tooling in *before* more __read_only usage is added. -- 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/