From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6922AECDE44 for ; Fri, 26 Oct 2018 09:32:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2C6622082D for ; Fri, 26 Oct 2018 09:32:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="a4ZTkaJY" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2C6622082D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727355AbeJZSIg (ORCPT ); Fri, 26 Oct 2018 14:08:36 -0400 Received: from bombadil.infradead.org ([198.137.202.133]:55292 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726128AbeJZSIg (ORCPT ); Fri, 26 Oct 2018 14:08:36 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=iRzSzFfMpJPH5fWYU91iQwZk+vLFmG/YAbr0c3Dc980=; b=a4ZTkaJYY6UngxYjKqMogy9/S HIV/j3fehVFN6rAVhiujGZkzp7FVtpWwQa/6V/wTf9Oj+g65tNwNRUAnxtj7UkdB1RsSgUdS+pP1s 4PTZnD5nTxEr10qCXeDLv8CvEh6SDL8jb64POwb3yZ3nnHHrhXBkI0VCLsGpoOE+Mpkx1qV9QA8oE ngvSehZv6QSQtOfvoMJLE9GSwKYehbMsAt/ib9PW8+Msxe4ar+dgjrDDpxFb7OBYqZlMhGVW99Ftx OlQ6y8agO7uMwCRSKeFF9Bp7xGMi7pvsiAiru+/FAmHgApv3XEnDngoFlXab7EI8ChMvpLCexzBgf UIIT92xUg==; Received: from [167.98.65.38] (helo=worktop) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1gFyTP-0000hB-69; Fri, 26 Oct 2018 09:32:07 +0000 Received: by worktop (Postfix, from userid 1000) id 39F196E07BE; Fri, 26 Oct 2018 11:32:05 +0200 (CEST) Date: Fri, 26 Oct 2018 11:32:05 +0200 From: Peter Zijlstra To: Igor Stoppa Cc: Mimi Zohar , Kees Cook , Matthew Wilcox , Dave Chinner , James Morris , Michal Hocko , kernel-hardening@lists.openwall.com, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, igor.stoppa@huawei.com, Dave Hansen , Jonathan Corbet , Laura Abbott , Greg Kroah-Hartman , Andrew Morton , Masahiro Yamada , Alexey Dobriyan , Pekka Enberg , "Paul E. McKenney" , Lihao Liang , linux-kernel@vger.kernel.org Subject: Re: [PATCH 13/17] prmem: linked list: disable layout randomization Message-ID: <20181026093205.GD3159@worktop.c.hoisthospitality.com> References: <20181023213504.28905-1-igor.stoppa@huawei.com> <20181023213504.28905-14-igor.stoppa@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181023213504.28905-14-igor.stoppa@huawei.com> User-Agent: Mutt/1.5.22.1 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 24, 2018 at 12:35:00AM +0300, Igor Stoppa wrote: > Some of the data structures used in list management are composed by two > pointers. Since the kernel is now configured by default to randomize the > layout of data structures soleley composed by pointers, this might > prevent correct type punning between these structures and their write > rare counterpart. 'might' doesn't really work for me. Either it does or it does not.