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=-5.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,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 A210CC432C0 for ; Mon, 2 Dec 2019 20:40:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 64BBC2071E for ; Mon, 2 Dec 2019 20:40:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Qq+rdPof" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725899AbfLBUkP (ORCPT ); Mon, 2 Dec 2019 15:40:15 -0500 Received: from mail-yw1-f66.google.com ([209.85.161.66]:46519 "EHLO mail-yw1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725874AbfLBUkO (ORCPT ); Mon, 2 Dec 2019 15:40:14 -0500 Received: by mail-yw1-f66.google.com with SMTP id u139so335022ywf.13 for ; Mon, 02 Dec 2019 12:40:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:autocrypt:message-id:date :mime-version:in-reply-to:content-transfer-encoding:content-language; bh=qsE7c9ZgxOSQwoJyGpg9QsvPMFkct0qAMYbSmWFxIV0=; b=Qq+rdPofQKdeXwZ00qSaFE+DEqSZGM7GRqAhD6uSWxZ1JscIqcI7V1hvG5ovS+gZq8 foE3OgdyaJRORgT/uhDMficm2F+yyK6gWHQ3u8czXqjO+wWaptqjHsFWcPVsBQf0+VcZ KiNl5AZeIj9IeXiaIPHC33kKx12u4V5A+lpI5NRTNUZWPUNAGvgvdh3ngC9cH+oEGHVx pQbOjZ0cMC2hfq2Mvko7vdUGgJ8PnP/T38g616J1ORCHUWI/qYx5CJ/9Nxtm/r5j6oRF WbL8LXTuxp54j4guxGRk3bz2FaxlrOvIgnPdbW1KIVh1dOmaftcYChPEoYfYYj57iHJ5 HY9g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:autocrypt :message-id:date:mime-version:in-reply-to:content-transfer-encoding :content-language; bh=qsE7c9ZgxOSQwoJyGpg9QsvPMFkct0qAMYbSmWFxIV0=; b=ZpXuBiAUOyG64WTo3q7T003L1prQ96sozYoV0w9H7/xnP9+AurF2Ibra/qFtHPMSad tStx4nb5Fl4sAZkZ0O+yU2HiIbYreeeD1ryVrsvYaCbHoU+OsZSdbL7rlM+SIEbuI+mw B4JhcqCCfjQqcwXPt5ozFBjHiUzlowbjPiDbhfNs1jQflQa8RvgtELRKrWdSRUDFK8mY yNcnmjO44SISzTf6Ng3GSrfudRsAKbHquuSXiPvC6GtObf08RAkZAUKnG4/3n9zBzhN0 mJ9iouM0OAVFiCm/wFD/V/mLIluUloApOWBReoLLy1ZbEMoyJHR9c+/MVfzRS9B+rV3i LsNg== X-Gm-Message-State: APjAAAU5QqNfKenrIAEnrKtkI9TXpJfLgOKRxMavX1kgmSPPaTwR8Hiv 2+9KTca3kODrriKzoZKPCdg= X-Google-Smtp-Source: APXvYqzVAwW2I32B/0xAxPyd/hpN3BBL+eKT4AVQ4l4H+N3Lwjb8UH+pAZdMslVt5hcN+nevt+rhOQ== X-Received: by 2002:a0d:d50d:: with SMTP id x13mr530885ywd.431.1575319213281; Mon, 02 Dec 2019 12:40:13 -0800 (PST) Received: from [10.77.0.2] (173-17-41-233.client.mchsi.com. [173.17.41.233]) by smtp.gmail.com with ESMTPSA id d138sm370719ywe.102.2019.12.02.12.40.09 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 02 Dec 2019 12:40:12 -0800 (PST) Subject: Re: [PATCH] Kernel Lockdown: Add an option to allow raw MSR access even, in confidentiality mode. To: Matthew Garrett Cc: LSM List , David Howells , matthew.garrett@nebula.com, Kees Cook References: <339ca47a-6ed1-4ab4-f8cf-7b205fa9f773@gmail.com> From: Matt Parnell Autocrypt: addr=mparnell@gmail.com; prefer-encrypt=mutual; keydata= mQINBFo3GdQBEADtjJfHcx+4ZWkygvBe298oW4OwHbF0iLJd/+yOObV/2/F2hHNvIsnY0syy ew0pdCBGbzhUlQbzIGEI1aBiikFP/g7zbWGf2r1Gkye+vka252dPZbeCW+reSbMQ6wsSpaLN tKvhwq7gIRQjMrSIXtLF/idxMzcd6R0r+DD2cojhktj/qsfhGArigjsuCedX5xFHHjM368Du o8FhTteNZePd8VoA7INrDmSUtEp1OOP98UCCr1bIO1K1AvMxHfAhqhEELXDZDgp3UgaIn24q SxqNDfNExSnqjMUPafGW3Gxq8hez5hmTrvml14v8VT3B/TIbqzOOH0CWxwTNUkq3gOjrZWcZ X4giVsBhZtFckr1KIMOl0IbL9N1El20LxPiqqQDrg633s4+22pKDq9c9JLuNSCHpXVaIaDS4 mY36SWCXNkO1QZn1NrIjctTjqmSzqH2w7borNUbtQLnnCo9SBXnCP9tO7pM4SI8dN0ehE9tP mQjNyPQjCCCaVMCAx69qTSKhIHQ9flnDbW+NNY3rFdN/IlpEqmZaFC21b+xRwEYys9MOdumR WVv4+mjMUkoyNRwtMg1W6WUhcQ0VczmTiczgztjTAJy3NjVfklIT1t6jM8n2yJOoUzLmp7DP 4dJmHpmUa73ITH6FtbOqE2AhOMFlXDxsNvPE8ukiWotP+m+xSwARAQABtCFNYXR0IFBhcm5l bGwgPG1wYXJuZWxsQGdtYWlsLmNvbT6JAlQEEwEIAD4WIQTLFpSDKxWZjIp7E2+53Q5PJNJa oAUCWjcZ1AIbIwUJCWYBgAULCQgHAgYVCAkKCwIEFgIDAQIeAQIXgAAKCRC53Q5PJNJaoJaa EACoF+DCyEZAkDAa+E+Mj0molEY41CmRmJGzsMd+Uhh7ZdLc65FqxDyN59w4DOEcFVUef95F YAjyhDrvf17EUS12R1TZ5h31akBsAKk0KR81W0ZCvI6/iS1ChZ0+wG+GedNxwp3YY+8gvnix B6/W3kmgHqBJAHGtlEjzGhkoHzsyc/+f0IsCd3G/bB6ZJLOQbqCKPS8YtaSflWt9SlPsHB9D +JjbsNT7Kn05ygeeF2J25L/q+Dwy9W0p2TByb2HAZpma2U4MIUUdCtrEQ7xMQ79xFqakBuKT f3dp2RJYXTeRkbFrsuycX60hH9flJZPZ6Q5wGCWzhiApjYy+mhnCzvrAuyvuuozvLxJ0M6Wk zCMMFFVnQNypYZTUYwXICb2oo4HcN50U5ZkzzWAjCLJg90ZioD/7fCO7rOs301GsB6rV94ah ktt+ma7a+hu25EZinAiTGFDk3n2G40rtELkphH+GIZYCrKrGcnEhicuGEAzi5+TewWnfLVTm wRVfXPMMcKFTV6XEUjWYGtgG4yxAjjBFqIY0XtT1GzpVVNzg90SW3ABD9dTSfsqk2MugrgPa /zELohio/V/O7Zm26BnhPi5sfK3T0AeDLqHwJrup5Osd2tf5zx3b3uFCRd1Jf8uoAZIBmKmH oios8sXRXOKy3dJEvtyeRZ9ai6lsNwaid2+zoLkCDQRaNxnUARAAu0Vk93D3ETcFVtb3uszZ K2Rzd6Wa3PJDnQ0PC4ER0ZK8QZg6I0rFlsxYWf8d9SghI5aXxtqcsyTiVoIPhCtH3KXt7nDU bsOlwP43KTX4VhlT4ocGpJb0DvfryjD3HD68IOeyvrsPWgf64Vk0CWYFSGYfBIC8ydew4YOT g6n/h/qrNhSMZTTJwNmXaHxPQy6OeMggu/5ZMylJTZ6Rs8inKLDs1/Wa584coH9npX2xsl9o GyBv2cIzz9fNmpLuRc+QWFeFtFuiZhd09GIEtbwH+qzo+8wq7lJxedEiePXYa4KfKigGmfTk D1W+WTGvF1Ui1uIljDZCRhMZlfIFcmwSeNLMjexaQboQnfS+qgnrwNkvN80azJd0wUcmsTAm A5ES4QleM0U1b/0YcoGni0ES1FgebLbptj8R1eem5ZTXJ4pxm5IZCmaYgv2rJwTl4dDYxUVO A8ATQUQ4tPPclk8FECfG1k/fGLpyku2n3rUFMTv4JGCZvHrTuy4BPQAwztVAxPw3Qx85TlwI 5U9npigZa3tNuXrvOXfJzwZZaedCFf2JjJYBpWEYDDqdUXdj38hpOeZszwgRyWCqrxUSi1O6 DoChrBlM2ETBQ9WG38TDQ1CyAXI8ctm8anUfVgVyDbbUTaHw61S+Nn4w9fj1sA4+q9hSsIlM xTXxMgpAfPwQ7kUAEQEAAYkCPAQYAQgAJhYhBMsWlIMrFZmMinsTb7ndDk8k0lqgBQJaNxnU AhsMBQkJZgGAAAoJELndDk8k0lqgcMoP/iaPjCViJAoae8/x8IGykah8l7QYjJWraxKuNI4C wYL9Hmm4pr6C3vtckOKs678QdB3Js6sfuD6eCQowTLQEBrP7LJU0Cw0S4x0oaSw7i1aySTIa QuPc5gjuqmZa7NeP0/sY/Is43b2mePf5ETTbcJM3PA44xkjQ21qR05pbF5ISlDqKvDog60dE /dDAnlFkP7H8PPmuXnqcaW1isPoBIZOsNY1Lt91rogTgvKXiIvz+ze2VYuBaEpyqJfchkwfR oUEQGljjXn5E98KfCDqou0gcP14BKBP45XhlD121PyoNgs/zCWpeAkrerctpl579hVrfg2yT gMsRsE9dlOdBsB1RAhB0Tmtqn75uBCKU3SCBgP/GZ0ZvoBiF+YQk/a5BFjQK1BsEdtXkwJxY mCGMPE3C0ADjxKUTx7wnmineBjc9B3yDugN7efpwHfltM6kKkbHNGoUz95Nhdp00GMYiwpcW EGbY1YzYACwMFwyWLaO8wWVo5MDe28OLpKbjHz3Zlu7E4gIJx3jId4coWSV7X1oAnq0JGUSO ypEChR786n/GobJlYw5UDWUJsmOFB9IXzt7o3YyKibpjPMmQY4tPUc137cJrbjsXU22fYrZn BPsD42iWdKVVoEd04MIj6OvIZCNHBRZA8Bly8xKPSLJIWNG0YZ7ETA0070lPmh9s3xqW Message-ID: <38d18a24-c580-d56b-f0cd-91e8184e1f0d@gmail.com> Date: Mon, 2 Dec 2019 14:39:41 -0600 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: Agreed. That said, if we don't mind working with what already exists, this whitelist addition (I have trouble calling it a module) exists. I wonder if it could be reshaped into something that ties in with the lockdown functionality? It looks like a mixture of commits from Intel engineers and Lawrence Livermore engineers (GPLv3) : https://github.com/LLNL/msr-safe On 12/2/19 1:43 PM, Matthew Garrett wrote: > On Fri, Nov 29, 2019 at 10:50 PM Matt Parnell wrote: >> For Intel CPUs, some of the MDS mitigations utilize the new "flush" MSR, and >> while this isn't something normally used in userspace, it does cause false >> positives for the "Forshadow" vulnerability. > The msr interface is pretty terrible - it exposes a consistent > interface over very inconsistent CPUs. Where there's CPU functionality > that's implemented via MSRs it makes sense to expose that over a > separate kernel interface.