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=ham 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 E102DC10F13 for ; Mon, 8 Apr 2019 17:15:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B06BA20883 for ; Mon, 8 Apr 2019 17:15:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="m1qMCOsB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729214AbfDHRPD (ORCPT ); Mon, 8 Apr 2019 13:15:03 -0400 Received: from mail-vk1-f193.google.com ([209.85.221.193]:35305 "EHLO mail-vk1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728664AbfDHRPD (ORCPT ); Mon, 8 Apr 2019 13:15:03 -0400 Received: by mail-vk1-f193.google.com with SMTP id g24so3211361vki.2 for ; Mon, 08 Apr 2019 10:15:02 -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=QNWxSEIPMq1gVan1P/8rBi8me5fnDngA88A2J0wyez0=; b=m1qMCOsBlIXzuJ74McEigabTnfzq67MTjoovacD7MOq/P0+rxbTH4vODORI4YzPR5j NtVORIrqXgx/HssokPsVYjSdzPVPx7BNl4fGDIgkMqW0+P+1QdcND5mNUDMOVQumgn0r LyNd5ragFy+2K5g5Samd3XvtJo44OWd91QKbU= 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=QNWxSEIPMq1gVan1P/8rBi8me5fnDngA88A2J0wyez0=; b=WJVk84tUEdNuDS0AUbUoWUOdLoH0U3JReyWIoKaNvJmho4Vxb952SY5kAOrTv8gbTN TijWUn6bKVVbozoTMk3GCbEeIDdmqa8zTnac3PykzFGB93EanxZyR6S0R74kzjk6gpfo XbN32eZywwzGMDtr6sPKQc94v4SD0MySiqjrBEIkl2a1g7WGeqTFgMSvzNj8rbriBxCk F3C1tqz1AnjXIGlqkMQsFzlbB9WZ7Ht+WJllYCHfe1WVKxGwSvmn4AVEUu7GD8mcaR5T mf4YH9LbHoMmHa/GtvZOG+dX5pGR1lvSxAe//tjTxpPf3ANPvqlehT31zELQZ4EQsomE blVA== X-Gm-Message-State: APjAAAUtiiNciOavgdev8zmW0K3DoDtx43B9y1bbDq2qwqOMPWYw6Cy7 k8dToAU1FnxECz5WHwcmDeJYkSjSrOA= X-Google-Smtp-Source: APXvYqz3ZiQLnzkF9CJi0AapWR/0QSbE9FBrcxLPbIAiI5AAfVDc9cqZJfDOMinWEghTFFsWOcx6Qg== X-Received: by 2002:a1f:a4d:: with SMTP id 74mr17197182vkk.13.1554743701603; Mon, 08 Apr 2019 10:15:01 -0700 (PDT) Received: from mail-vs1-f54.google.com (mail-vs1-f54.google.com. [209.85.217.54]) by smtp.gmail.com with ESMTPSA id u6sm23820733vke.54.2019.04.08.10.14.58 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 08 Apr 2019 10:14:59 -0700 (PDT) Received: by mail-vs1-f54.google.com with SMTP id o10so5473605vsp.12 for ; Mon, 08 Apr 2019 10:14:58 -0700 (PDT) X-Received: by 2002:a67:7e12:: with SMTP id z18mr18237223vsc.82.1554743697591; Mon, 08 Apr 2019 10:14:57 -0700 (PDT) MIME-Version: 1.0 References: <20190308132701.133598-1-glider@google.com> <20190308132701.133598-3-glider@google.com> <497b1201-b2ae-5e0c-d191-ff1830d92fc1@redhat.com> In-Reply-To: <497b1201-b2ae-5e0c-d191-ff1830d92fc1@redhat.com> From: Kees Cook Date: Mon, 8 Apr 2019 10:14:45 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 2/2] initmem: introduce CONFIG_INIT_ALL_HEAP To: Laura Abbott Cc: Alexander Potapenko , Masahiro Yamada , James Morris , "Serge E. Hallyn" , linux-security-module , linux-kbuild , Nick Desaulniers , Kostya Serebryany , Dmitry Vyukov , Sandeep Patil , Kernel Hardening Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: On Mon, Apr 8, 2019 at 9:43 AM Laura Abbott wrote: > I've looked at doing something similar in the past (failing to find > the thread this morning...) and while this will work, it has pretty > serious performance issues. It's not actually the poisoning which > is expensive but that turning on debugging removes the cpu slab > which has significant performance penalties. > > I'd rather go back to the proposal of just poisoning the slab > at alloc/free without using SLAB_POISON. I still agree this would make the most sense. Fundamentally it's not a debugging feature. -- Kees Cook