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=-9.0 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 B6BE1C282F6 for ; Mon, 21 Jan 2019 08:39:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 88BD920861 for ; Mon, 21 Jan 2019 08:39:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=mena-vt-edu.20150623.gappssmtp.com header.i=@mena-vt-edu.20150623.gappssmtp.com header.b="BdDxLGM1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729392AbfAUIjj (ORCPT ); Mon, 21 Jan 2019 03:39:39 -0500 Received: from mail-wm1-f66.google.com ([209.85.128.66]:40776 "EHLO mail-wm1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728973AbfAUIji (ORCPT ); Mon, 21 Jan 2019 03:39:38 -0500 Received: by mail-wm1-f66.google.com with SMTP id f188so9809834wmf.5 for ; Mon, 21 Jan 2019 00:39:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mena-vt-edu.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=S5NVvoOgAgdZo8wmN11QDMw/7RKccGkERCz5dFRhs3I=; b=BdDxLGM1dmo0GQ+oCKzyAyW/P0iJv04mOqd5KTQC7iP2RnAShme5aGa8+eljPHQD5R 9UmVk6y1JS7PQ1SLhctISAowhr2r0ah2arCKYzHwcPIMBUI450ApL7L8k0GqISPqpioD UxI4E6VVT0p3jaEWvnULiJntikx2nuzcq1kWXgGHNp3baPwmjmhoIgkO7KuC6y813yud zvXyPUwiIOeN+gu9q5I5gKTTvdXNundyTG6tPOqDVEezJVRkPGQ+ow29IgF9qiH/lwsP cnQMPZD9X9blbOT7wc7fTFkK8bEjOwn4Wu1NeUueXVV60brUtY0RSwlBTv9y0t/tG3Nh GlJw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=S5NVvoOgAgdZo8wmN11QDMw/7RKccGkERCz5dFRhs3I=; b=RIgAUFUvjOez0YpTjOWnBDtX31Itrn2sG1lWKZEy+gtUjasR+v7yQLk/idtaqyTJ6a W4ofp/qJiQWqiWoArcj3nPOA8nXVhFmuLhneMwX4UhxWUu9+GvBeknHO/isdbZcPuEyr 31ZjS16wFA3TxjhzVG0S64MRovemEDzrHldZzNQswZQFGzapx+La2er5Ja5CB8qWI36A Rr4glJ4mrKBv1UKIH4jhiXJ9SQN6Fsxitq/PtLzl2LuDGQr/zsX7bB/xU3yWVdBV5ZF4 pCmB+XS1Xt9y2ma+/+ZCJZZVunBBZvGUXtLgRLLRoJ61si/IE168TamF+kCT2lQEYH18 2g5Q== X-Gm-Message-State: AJcUukdFHXGxZDb+XDm0rIQltCQ1W17JiimDYxwNTbfuwLNp0OjfR4TK CYi8YI9cjmO4FO+sbnYB7awgKWUQfBA= X-Google-Smtp-Source: ALg8bN4kc5ObGqv6NoNo2QHDN6CCtu/mF6luBJqOGiE2VJKAp52yGhiJxl9kbMkt/ISKNQ1uC0ZBkw== X-Received: by 2002:a1c:7409:: with SMTP id p9mr23272500wmc.136.1548027677700; Sun, 20 Jan 2019 15:41:17 -0800 (PST) Received: from localhost.localdomain ([156.212.82.83]) by smtp.gmail.com with ESMTPSA id e9sm76576753wro.16.2019.01.20.15.41.14 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 20 Jan 2019 15:41:17 -0800 (PST) From: Ahmed Abd El Mawgood To: Paolo Bonzini , rkrcmar@redhat.com, Jonathan Corbet , Thomas Gleixner , Ingo Molnar , Borislav Petkov , hpa@zytor.com, x86@kernel.org, kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, ahmedsoliman0x666@gmail.com, ovich00@gmail.com, kernel-hardening@lists.openwall.com, nigel.edwards@hpe.com, Boris Lukashev , Igor Stoppa Cc: Ahmed Abd El Mawgood Subject: [RESEND PATCH V8 04/11] KVM: Document Memory ROE Date: Mon, 21 Jan 2019 01:39:33 +0200 Message-Id: <20190120233940.15282-5-ahmedsoliman@mena.vt.edu> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20190120233940.15282-1-ahmedsoliman@mena.vt.edu> References: <20190120233940.15282-1-ahmedsoliman@mena.vt.edu> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ROE version documented here is implemented in the next 2 patches Signed-off-by: Ahmed Abd El Mawgood --- Documentation/virtual/kvm/hypercalls.txt | 40 ++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/Documentation/virtual/kvm/hypercalls.txt b/Documentation/virtual/kvm/hypercalls.txt index da24c138c8..a31f316ce6 100644 --- a/Documentation/virtual/kvm/hypercalls.txt +++ b/Documentation/virtual/kvm/hypercalls.txt @@ -141,3 +141,43 @@ a0 corresponds to the APIC ID in the third argument (a2), bit 1 corresponds to the APIC ID a2+1, and so on. Returns the number of CPUs to which the IPIs were delivered successfully. + +7. KVM_HC_ROE +---------------- +Architecture: x86 +Status: active +Purpose: Hypercall used to apply Read-Only Enforcement to guest memory and +registers +Usage 1: + a0: ROE_VERSION + +Returns non-signed number that represents the current version of ROE +implementation current version. + +Usage 2: + + a0: ROE_MPROTECT (requires version >= 1) + a1: Start address aligned to page boundary. + a2: Number of pages to be protected. + +This configuration lets a guest kernel have part of its read/write memory +converted into read-only. This action is irreversible. +Upon successful run, the number of pages protected is returned. + +Usage 3: + a0: ROE_MPROTECT_CHUNK (requires version >= 2) + a1: Start address aligned to page boundary. + a2: Number of bytes to be protected. +This configuration lets a guest kernel have part of its read/write memory +converted into read-only with bytes granularity. ROE_MPROTECT_CHUNK is +relatively slow compared to ROE_MPROTECT. This action is irreversible. +Upon successful run, the number of bytes protected is returned. + +Error codes: + -KVM_ENOSYS: system call being triggered from ring 3 or it is not + implemented. + -EINVAL: error based on given parameters. + +Notes: KVM_HC_ROE can not be triggered from guest Ring 3 (user mode). The +reason is that user mode malicious software can make use of it to enforce read +only protection on an arbitrary memory page thus crashing the kernel. -- 2.19.2