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,URIBL_BLOCKED, USER_AGENT_SANE_1 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 5BFA4C32750 for ; Fri, 2 Aug 2019 16:15:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3B91E20449 for ; Fri, 2 Aug 2019 16:15:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390275AbfHBQPk (ORCPT ); Fri, 2 Aug 2019 12:15:40 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:58930 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732543AbfHBQPk (ORCPT ); Fri, 2 Aug 2019 12:15:40 -0400 Received: from 162-237-133-238.lightspeed.rcsntx.sbcglobal.net ([162.237.133.238] helo=elm) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1htaDM-0004rZ-SG; Fri, 02 Aug 2019 16:15:33 +0000 Date: Fri, 2 Aug 2019 11:15:28 -0500 From: Tyler Hicks To: Roberto Sassu Cc: jarkko.sakkinen@linux.intel.com, jejb@linux.ibm.com, zohar@linux.ibm.com, jgg@ziepe.ca, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, keyrings@vger.kernel.org, linux-kernel@vger.kernel.org, crazyt2019+lml@gmail.com, nayna@linux.vnet.ibm.com, silviu.vlasceanu@huawei.com Subject: Re: [PATCH v2] KEYS: trusted: allow module init if TPM is inactive or deactivated Message-ID: <20190802161527.GC26616@elm> References: <20190802150733.1972-1-roberto.sassu@huawei.com> <20190802153030.GB26616@elm> <3222714a-a280-0708-f4c0-5db6d342d8dc@huawei.com> <8baf1c39-ad04-5cd6-bc67-341e7411db16@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <8baf1c39-ad04-5cd6-bc67-341e7411db16@huawei.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: On 2019-08-02 18:11:09, Roberto Sassu wrote: > On 8/2/2019 5:34 PM, Roberto Sassu wrote: > > On 8/2/2019 5:30 PM, Tyler Hicks wrote: > > > On 2019-08-02 17:07:33, Roberto Sassu wrote: > > > > Commit c78719203fc6 ("KEYS: trusted: allow trusted.ko to > > > > initialize w/o a > > > > TPM") allows the trusted module to be loaded even a TPM is not found to > > >                                                     ^ if > > > > > > > avoid module dependency problems. > > > > > > > > However, trusted module initialization can still fail if the TPM is > > > > inactive or deactivated. This patch ignores tpm_get_random() errors in > > > > init_digests() and returns -EFAULT in pcrlock() if the TPM didn't return > > > > random data. > > > > > > > > Signed-off-by: Roberto Sassu > > > > > > The code changes look correct to me. > > > > > >    Reviewed-by: Tyler Hicks > > > > > > For whoever takes this patch through their tree, I think that adding the > > > following Fixes tag would be useful (as well as cc'ing stable): > > > > > >    Fixes: 240730437deb ("KEYS: trusted: explicitly use tpm_chip > > > structure...") > > > > > > I think it is also worth leaving a short note, in the commit message, > > > for backporters that commit 782779b60faa ("tpm: Actually fail on TPM > > > errors during "get random"") should be included with any backports of > > > this patch. > > > > Right, thanks. I wait for Jarkko's comments and I add both the Fixes tag > > and the short note in the next version of the patch. > > Uhm, I was thinking that maybe it is not necessary to mention commit > 782779b60faa. This patch would still return 0 even if that commit is not > backported (TPM_ERR_DISABLED < TPM_MAX_DIGEST_SIZE). The commit message for 782779b60faa shows 379 being returned when attempting to get random: [ 18.092103] tpm tpm0: A TPM error (379) occurred attempting get random I don't know enough about TPM chips to know how common that is... Tyler > > Roberto > > -- > HUAWEI TECHNOLOGIES Duesseldorf GmbH, HRB 56063 > Managing Director: Li Peng, Li Jian, Shi Yanli