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=-5.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_MUTT 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 5F3C9C31E41 for ; Mon, 10 Jun 2019 15:27:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3E338212F5 for ; Mon, 10 Jun 2019 15:27:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390281AbfFJP12 (ORCPT ); Mon, 10 Jun 2019 11:27:28 -0400 Received: from mga17.intel.com ([192.55.52.151]:21589 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390177AbfFJP12 (ORCPT ); Mon, 10 Jun 2019 11:27:28 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga107.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 10 Jun 2019 08:27:28 -0700 X-ExtLoop1: 1 Received: from agusev-mobl.ger.corp.intel.com (HELO localhost) ([10.249.46.248]) by fmsmga001.fm.intel.com with ESMTP; 10 Jun 2019 08:27:17 -0700 Date: Mon, 10 Jun 2019 18:27:17 +0300 From: Jarkko Sakkinen To: Sean Christopherson Cc: Andy Lutomirski , Cedric Xing , Stephen Smalley , James Morris , "Serge E . Hallyn" , LSM List , Paul Moore , Eric Paris , selinux@vger.kernel.org, Jethro Beekman , Dave Hansen , Thomas Gleixner , Linus Torvalds , LKML , X86 ML , linux-sgx@vger.kernel.org, Andrew Morton , nhorman@redhat.com, npmccallum@redhat.com, Serge Ayoun , Shay Katz-zamir , Haitao Huang , Andy Shevchenko , Kai Svahn , Borislav Petkov , Josh Triplett , Kai Huang , David Rientjes , William Roberts , Philip Tricca Subject: Re: [RFC PATCH v2 2/5] x86/sgx: Require userspace to define enclave pages' protection bits Message-ID: <20190610152717.GB3752@linux.intel.com> References: <20190606021145.12604-1-sean.j.christopherson@intel.com> <20190606021145.12604-3-sean.j.christopherson@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190606021145.12604-3-sean.j.christopherson@intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-sgx-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org On Wed, Jun 05, 2019 at 07:11:42PM -0700, Sean Christopherson wrote: > [SNAP] Same general criticism as for the previous patch: try to say things as they are without anything extra. > A third alternative would be to pull the protection bits from the page's > SECINFO, i.e. make decisions based on the protections enforced by > hardware. However, with SGX2, userspace can extend the hardware- > enforced protections via ENCLU[EMODPE], e.g. can add a page as RW and > later convert it to RX. With SGX2, making a decision based on the > initial protections would either create a security hole or force SGX to > dynamically track "dirty" pages (see first alternative above). > > Signed-off-by: Sean Christopherson 'flags' should would renamed as 'secinfo_flags_mask' even if the name is longish. It would use the same values as the SECINFO flags. The field in struct sgx_encl_page should have the same name. That would express exactly relation between SECINFO and the new field. I would have never asked on last iteration why SECINFO is not enough with a better naming. The same field can be also used to cage page type to a subset of values. /Jarkko