From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751184AbdAQThj (ORCPT ); Tue, 17 Jan 2017 14:37:39 -0500 Received: from r00tworld.com ([212.85.137.150]:38364 "EHLO r00tworld.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751106AbdAQThg (ORCPT ); Tue, 17 Jan 2017 14:37:36 -0500 From: "PaX Team" To: Mark Rutland Date: Tue, 17 Jan 2017 19:54:38 +0100 MIME-Version: 1.0 Subject: Re: [PATCH] gcc-plugins: Add structleak for more stack initialization Reply-to: pageexec@freemail.hu CC: kernel-hardening@lists.openwall.com, Kees Cook , Emese Revfy , "AKASHI, Takahiro" , park jinbum , Daniel Micay , linux-kernel@vger.kernel.org, spender@grsecurity.net Message-ID: <587E686E.29386.DA7FA27@pageexec.freemail.hu> In-reply-to: <20170117174831.GB367@leverpostej> References: <20170113220256.GA57663@beast>, <587D1F55.2222.8A262A4@pageexec.freemail.hu>, <20170117174831.GB367@leverpostej> X-mailer: Pegasus Mail for Windows (4.72.572) 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]); Tue, 17 Jan 2017 19:54:39 +0100 (CET) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 17 Jan 2017 at 17:48, Mark Rutland wrote: > That being the case, (and given the relevant bug has now been fixed), > it's not clear to me what the value of this is today. i.e. given the > general case, is this preventing many leaks? no idea, i stopped looking at the instrumentation log long ago, but everyone can enable the debug output (has a very specific comment on it ;) and look at the results. i keep this plugin around because it costs nothing to maintain it and the alternative (better) solution doesn't exist yet. > > i never went into that direction because i think the security goal can > > be achieved without the performance impact of forced initialization. > > Was there a particular technique you had in mind? sure, i mentioned it in my SSTIC'12 keynote (page 36): https://pax.grsecurity.net/docs/PaXTeam-SSTIC12-keynote-20-years-of-PaX.pdf