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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT autolearn=unavailable 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 9952FC04E87 for ; Thu, 16 May 2019 07:02:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7316A20862 for ; Thu, 16 May 2019 07:02:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726652AbfEPHCt (ORCPT ); Thu, 16 May 2019 03:02:49 -0400 Received: from mga07.intel.com ([134.134.136.100]:16965 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726319AbfEPHCt (ORCPT ); Thu, 16 May 2019 03:02:49 -0400 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga105.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 May 2019 00:02:47 -0700 X-ExtLoop1: 1 Received: from odonnabh-mobl.ger.corp.intel.com (HELO localhost) ([10.252.32.47]) by fmsmga007.fm.intel.com with ESMTP; 16 May 2019 00:02:38 -0700 Date: Thu, 16 May 2019 10:02:36 +0300 From: Jarkko Sakkinen To: Andy Lutomirski Cc: Sean Christopherson , Andy Lutomirski , Jethro Beekman , "Xing, Cedric" , "Hansen, Dave" , Thomas Gleixner , "Dr. Greg" , Linus Torvalds , LKML , X86 ML , "linux-sgx@vger.kernel.org" , Andrew Morton , "nhorman@redhat.com" , "npmccallum@redhat.com" , "Ayoun, Serge" , "Katz-zamir, Shay" , "Huang, Haitao" , Andy Shevchenko , "Svahn, Kai" , Borislav Petkov , Josh Triplett , "Huang, Kai" , David Rientjes Subject: Re: [PATCH v20 00/28] Intel SGX1 support Message-ID: <20190516070236.GA5589@linux.intel.com> References: <20190513102926.GD8743@linux.intel.com> <20190514104323.GA7591@linux.intel.com> <20190514204527.GC1977@linux.intel.com> <20190515103531.GB10917@linux.intel.com> <20190515110005.GA14718@linux.intel.com> <20190516050705.GB6388@linux.intel.com> <20190516065103.GA4642@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190516065103.GA4642@linux.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, May 16, 2019 at 09:51:03AM +0300, Jarkko Sakkinen wrote: > On Thu, May 16, 2019 at 08:07:05AM +0300, Jarkko Sakkinen wrote: > > On Wed, May 15, 2019 at 07:27:02AM -0700, Andy Lutomirski wrote: > > > > > > > On May 15, 2019, at 4:00 AM, Jarkko Sakkinen wrote: > > > > > > > >> On Wed, May 15, 2019 at 01:35:31PM +0300, Jarkko Sakkinen wrote: > > > >> This brings me to an open question in Andy's model: lets say that we > > > >> change the source for SIGSTRUCT from memory address to fd. How can the > > > >> policy prevent the use not creating a file containing a SIGSTRUCT and > > > >> passing fd of that to the EINIT ioctl? > > > > > > > > > > The policy will presumably check the label on the file that the fd points to. > > > > Right (checked SELinux documentation). > > > > Got one idea from this. Right now creation and initialization does not > > require any VMAs to be created (since v20). Requiring to map a VMA for > > copying the data would bring in my opinion a glitch to this model that > > we have done effort to build up. > > > > What if we similarly change EADD ioctl in a way that it'd take an fd > > and an offset? This way we can enforce policy to the source where the > > enclave data is loaded from. On the other hand, loading SIGSTRUCT from > > fd enforces a legit structure for the enclave. > > > > This would still allow to construct enclaves in VMA independent way. > > The API would turn into this: > > /** > * struct sgx_enclave_add_page - parameter structure for the > * %SGX_IOC_ENCLAVE_ADD_PAGE ioctl > * @fd: file containing the page data > * @offset: offset in the file containing the page data > * @secinfo: address for the SECINFO data > * @mrmask: bitmask for the measured 256 byte chunks > */ > struct sgx_enclave_add_page { > __u64 fd; > __u64 offset; > __u64 secinfo; > __u16 mrmask; > } __attribute__((__packed__)); > > > /** > * struct sgx_enclave_init - parameter structure for the > * %SGX_IOC_ENCLAVE_INIT ioctl > * @fd: file containing the sigstruct > * @offset: offset in the file containing the sigstruct > */ > struct sgx_enclave_init { > __u64 fd; > __u64 offset; > }; The change to EADD/EINIT ioctl's would be simply fget/kernel_read/fput sequence replacing copy_from_user(). /Jarkko