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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 CD0E9C31E40 for ; Fri, 9 Aug 2019 15:13:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AB1602171F for ; Fri, 9 Aug 2019 15:13:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2407300AbfHIPN0 (ORCPT ); Fri, 9 Aug 2019 11:13:26 -0400 Received: from mga12.intel.com ([192.55.52.136]:12308 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2406642AbfHIPN0 (ORCPT ); Fri, 9 Aug 2019 11:13:26 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 09 Aug 2019 08:13:26 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,364,1559545200"; d="scan'208";a="193406792" Received: from jsakkine-mobl1.tm.intel.com ([10.237.50.189]) by fmsmga001.fm.intel.com with ESMTP; 09 Aug 2019 08:13:24 -0700 Message-ID: <8f537adf9928ab47b29cb513de508b913458b74b.camel@linux.intel.com> Subject: Re: [PATCH for_v22 01/11] x86/sgx: Fix an SECS collision with enclave page at VA=0 From: Jarkko Sakkinen To: Sean Christopherson Cc: linux-sgx@vger.kernel.org, Shay Katz-zamir , Serge Ayoun Date: Fri, 09 Aug 2019 18:13:22 +0300 In-Reply-To: <20190808154412.GC23156@linux.intel.com> References: <20190808001254.11926-1-sean.j.christopherson@intel.com> <20190808001254.11926-2-sean.j.christopherson@intel.com> <20190808153434.tvrvpdl6o7yp2mje@linux.intel.com> <20190808154412.GC23156@linux.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.32.1-2 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-sgx-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org On Thu, 2019-08-08 at 08:44 -0700, Sean Christopherson wrote: > On Thu, Aug 08, 2019 at 06:34:59PM +0300, Jarkko Sakkinen wrote: > > On Wed, Aug 07, 2019 at 05:12:44PM -0700, Sean Christopherson wrote: > > > Detect the SECS in paging related flows by explicitly checking the page > > > against the enclave's SECS page. Assuming a page with VA=0 is the SECS > > > will break enclaves that actually use VA=0, which is extremely unlikely > > > but theoretically possible. > > > > > > Signed-off-by: Sean Christopherson > > > > I would define a macro to the same place where SGX_ENCL_PAGE_ADDR() is > > defined and also SGX_ENCL_PAGE_IS_SECS() would definitely more > > self-describing name. > > > > Can't you BTW just use the backpointer in struct sgx_encl_page to the > > enclave since we have it there? It is even set for SECS in > > sgx_encl_create(). > > Yeah, that would work too. I passed in @encl to match the format of > sgx_encl_get_index(), perhaps it makes sense to use the backpointer there > as well? Yes, it does of course. Probably have just forgotten to add it. This kind of inconsistencies exist because backpointer has not been always existing. /Jarkko