From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Sakkinen Date: Thu, 11 Jul 2019 19:48:11 +0000 Subject: Re: [PATCH] KEYS: trusted: allow module init if TPM is inactive or deactivated Message-Id: <20190711194811.rfsohbfc3a7carpa@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit List-Id: References: <20190705163735.11539-1-roberto.sassu@huawei.com> In-Reply-To: <20190705163735.11539-1-roberto.sassu@huawei.com> To: Roberto Sassu Cc: 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, tyhicks@canonical.com, nayna@linux.vnet.ibm.com, silviu.vlasceanu@huawei.com On Fri, Jul 05, 2019 at 06:37:35PM +0200, 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 > avoid module dependency problems. > > Unfortunately, this does not completely solve the issue, as there could be > a case where a TPM is found but is not functional (the TPM commands return > an error). Specifically, after the tpm_chip structure is returned by > tpm_default_chip() in init_trusted(), the execution terminates after > init_digests() returns -EFAULT (due to the fact that tpm_get_random() > returns a positive value, but less than TPM_MAX_DIGEST_SIZE). > > This patch fixes the issue by ignoring the TPM_ERR_DEACTIVATED and > TPM_ERR_DISABLED errors. Why allow trusted module to initialize if TPM is not functional? Also: err = tpm_transmit_cmd(chip, &buf, offsetof(struct tpm2_get_random_out, buffer), "attempting get random"); if (err) { if (err > 0) err = -EIO; goto out; } /Jarkko 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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 84172C742A1 for ; Thu, 11 Jul 2019 19:48:21 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5AA7720863 for ; Thu, 11 Jul 2019 19:48:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728951AbfGKTsU (ORCPT ); Thu, 11 Jul 2019 15:48:20 -0400 Received: from mga02.intel.com ([134.134.136.20]:42927 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728679AbfGKTsU (ORCPT ); Thu, 11 Jul 2019 15:48:20 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Jul 2019 12:48:19 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,479,1557212400"; d="scan'208";a="168116079" Received: from mmoerth-mobl6.ger.corp.intel.com (HELO localhost) ([10.249.35.82]) by fmsmga007.fm.intel.com with ESMTP; 11 Jul 2019 12:48:14 -0700 Date: Thu, 11 Jul 2019 22:48:11 +0300 From: Jarkko Sakkinen To: Roberto Sassu Cc: 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, tyhicks@canonical.com, nayna@linux.vnet.ibm.com, silviu.vlasceanu@huawei.com Subject: Re: [PATCH] KEYS: trusted: allow module init if TPM is inactive or deactivated Message-ID: <20190711194811.rfsohbfc3a7carpa@linux.intel.com> References: <20190705163735.11539-1-roberto.sassu@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190705163735.11539-1-roberto.sassu@huawei.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: NeoMutt/20180716 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 05, 2019 at 06:37:35PM +0200, 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 > avoid module dependency problems. > > Unfortunately, this does not completely solve the issue, as there could be > a case where a TPM is found but is not functional (the TPM commands return > an error). Specifically, after the tpm_chip structure is returned by > tpm_default_chip() in init_trusted(), the execution terminates after > init_digests() returns -EFAULT (due to the fact that tpm_get_random() > returns a positive value, but less than TPM_MAX_DIGEST_SIZE). > > This patch fixes the issue by ignoring the TPM_ERR_DEACTIVATED and > TPM_ERR_DISABLED errors. Why allow trusted module to initialize if TPM is not functional? Also: err = tpm_transmit_cmd(chip, &buf, offsetof(struct tpm2_get_random_out, buffer), "attempting get random"); if (err) { if (err > 0) err = -EIO; goto out; } /Jarkko