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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS 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 5F440C10F13 for ; Thu, 11 Apr 2019 20:37:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 231F72075B for ; Thu, 11 Apr 2019 20:37:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="Td0bi4W8" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726812AbfDKUgz (ORCPT ); Thu, 11 Apr 2019 16:36:55 -0400 Received: from mail-vs1-f49.google.com ([209.85.217.49]:37714 "EHLO mail-vs1-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726974AbfDKUgx (ORCPT ); Thu, 11 Apr 2019 16:36:53 -0400 Received: by mail-vs1-f49.google.com with SMTP id w13so4289988vsc.4 for ; Thu, 11 Apr 2019 13:36:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=LHThbCjbRRpzc8ii2OMzeBZem6XJJjKKjhIHY/St8eE=; b=Td0bi4W8T8i8LXYBoXjDvAZ16eEig1BUUpw2DskS8xfM6eLIhUg8UuHqaJIrZOj0Z5 Z9X23/3OWlGennv2Ucci7a5DC88uXNwtiU3TQuf+6FQoc8KIa7IaSt8l1uicTO6X5G9S L9BvpPxwMN6/OkVNChPSZIrA3XTQ+hRZ/9aRA= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=LHThbCjbRRpzc8ii2OMzeBZem6XJJjKKjhIHY/St8eE=; b=FxtTNXPoZxvR5X4r0KuGIZJlHjJsmcd4jEE14Qnige3ulCZAZsMnv6CabSZ2Zg85jv eseBXDDUaOA4OQ/67DEFumL03PV2djhVobFvQO43wX0hN9c9Fi5ZXCXMuIlgQhov22dY /7i8Uo5woTLpZaDFRS1CE/M3KW0domkNJzI72yTlKtEUxyFPktAH065GLMgOzMv3D7U8 GOdKBcUAP1yiKvLbf0JHG8J0C4IfKNKAS8T3MRBXUVazdT9y6Qy1FrNfHVfpd+UiuCHt 9MEQYXLXFDvrbGoyxkSoywBVfD/W0cQWsbv/YkprngPdvQSHEHFR3M9g8qv6wXYhR4c3 7bKQ== X-Gm-Message-State: APjAAAUZmr5QOIzuLXMJbPrAai0FUzFte6FmjnFkskN6PbvVvJK6boWn hMQSxmJ9lG1G/8FUgNIQID8fIkZk0lU= X-Google-Smtp-Source: APXvYqwmaxzrMCRHIkFlWb8JeOJzbq2lb2zCj4jCDT+smerWUsdIiPtFXIFVmuNBxAJApYmTqFFaMQ== X-Received: by 2002:a05:6102:212:: with SMTP id z18mr30056241vsp.218.1555015011204; Thu, 11 Apr 2019 13:36:51 -0700 (PDT) Received: from mail-vk1-f171.google.com (mail-vk1-f171.google.com. [209.85.221.171]) by smtp.gmail.com with ESMTPSA id 110sm29029030uaq.7.2019.04.11.13.36.49 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 11 Apr 2019 13:36:50 -0700 (PDT) Received: by mail-vk1-f171.google.com with SMTP id x84so1681598vkd.1 for ; Thu, 11 Apr 2019 13:36:49 -0700 (PDT) X-Received: by 2002:a1f:7d4e:: with SMTP id y75mr28798331vkc.53.1555015009326; Thu, 11 Apr 2019 13:36:49 -0700 (PDT) MIME-Version: 1.0 References: <20190321175122.GA1587@sol.localdomain> <20190410031734.GB7140@sol.localdomain> <20190410190729.GA120258@gmail.com> <20190410231156.GB120258@gmail.com> <20190411175823.GC225654@gmail.com> <20190411192607.GD225654@gmail.com> In-Reply-To: <20190411192607.GD225654@gmail.com> From: Kees Cook Date: Thu, 11 Apr 2019 13:36:37 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: crypto: Kernel memory overwrite attempt detected to spans multiple pages To: Eric Biggers Cc: Dmitry Vyukov , Geert Uytterhoeven , Herbert Xu , linux-security-module , Linux ARM , Linux Crypto Mailing List , Linux Kernel Mailing List , Laura Abbott , Rik van Riel Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: On Thu, Apr 11, 2019 at 12:26 PM Eric Biggers wrote: > Well, I guess I'll just add __GFP_COMP so I at least don't get spammed with > useless bug reports. Thanks, I appreciate it. > But I don't think it's in any way acceptable to change the semantics of the > kernel's page allocator but only under some obscure config option, don't > document it anywhere, ignore the known problems for years, say that the option > is broken anyway so it shouldn't be used, and have to exchange 15 emails to get > anything resembling an explanation. I understand what you mean, yeah. I'm sorry I wasn't clear about it earlier. What do you think might help the situation as far as documentation? -- Kees Cook