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=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 79BFDC4363D for ; Thu, 24 Sep 2020 19:29:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3EFBA221EB for ; Thu, 24 Sep 2020 19:29:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728840AbgIXT3O (ORCPT ); Thu, 24 Sep 2020 15:29:14 -0400 Received: from mga09.intel.com ([134.134.136.24]:55271 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728718AbgIXT3N (ORCPT ); Thu, 24 Sep 2020 15:29:13 -0400 IronPort-SDR: 0s7WgU6aLPCoXtkDhXLUm+FJTeUUZ25DhQe9KPeQjqswSw1GSL1GPO1a70rtP+7UWwuDyiMEFw MQcLvNkfOkqw== X-IronPort-AV: E=McAfee;i="6000,8403,9754"; a="162222615" X-IronPort-AV: E=Sophos;i="5.77,299,1596524400"; d="scan'208";a="162222615" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga004.jf.intel.com ([10.7.209.38]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Sep 2020 12:28:55 -0700 IronPort-SDR: /alJgHdzpr6m/E8oOg3GkCjvnAxXz1fHnWK/iozNJcTJB92wSlAKm5CGN1sqhOgLh0TVuK+3Qa 1UHE7REBvP9Q== X-IronPort-AV: E=Sophos;i="5.77,299,1596524400"; d="scan'208";a="455484772" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.160]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Sep 2020 12:28:55 -0700 Date: Thu, 24 Sep 2020 12:28:54 -0700 From: Sean Christopherson To: Haitao Huang Cc: Jarkko Sakkinen , Andy Lutomirski , X86 ML , linux-sgx@vger.kernel.org, LKML , Linux-MM , Andrew Morton , Matthew Wilcox , Jethro Beekman , Darren Kenny , Andy Shevchenko , asapek@google.com, Borislav Petkov , "Xing, Cedric" , chenalexchen@google.com, Conrad Parker , cyhanish@google.com, Dave Hansen , "Huang, Haitao" , Josh Triplett , "Huang, Kai" , "Svahn, Kai" , Keith Moyer , Christian Ludloff , Neil Horman , Nathaniel McCallum , Patrick Uiterwijk , David Rientjes , Thomas Gleixner , yaozhangx@google.com Subject: Re: [PATCH v38 10/24] mm: Add vm_ops->mprotect() Message-ID: <20200924192853.GA18826@linux.intel.com> References: <20200918235337.GA21189@sjchrist-ice> <20200921124946.GF6038@linux.intel.com> <20200921165758.GA24156@linux.intel.com> <20200921210736.GB58176@linux.intel.com> <20200921211849.GA25403@linux.intel.com> <20200922052957.GA97272@linux.intel.com> <20200922053515.GA97687@linux.intel.com> <20200922164301.GB30874@linux.intel.com> <20200923135056.GD5160@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org On Thu, Sep 24, 2020 at 02:11:37PM -0500, Haitao Huang wrote: > On Wed, 23 Sep 2020 08:50:56 -0500, Jarkko Sakkinen > wrote: > >I'll categorically deny noexec in the next patch set version. > > > >/Jarkko > > There are use cases supported currently in which enclave binary is received > via IPC/RPC and held in buffers before EADD. Denying noexec altogether would > break those, right? No. noexec only applies to file-backed VMAs, what you're describing is loading an enclave from an anon VMA, which will still have VM_MAYEXEC. I believe you're thinking of SELinux's EXECMEM, which is required to execute from anonymous memory, and which we talked about (more than once) applying to SGX enclaves. That being said, I still dislike the idea of requiring VM_MAYEXEC, it's a hack that doesn't really buy us much, if anything.