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_PASS,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 D5B26C04EBF for ; Wed, 5 Dec 2018 00:46:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 984752081C for ; Wed, 5 Dec 2018 00:46:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 984752081C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-security-module-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726001AbeLEAqs (ORCPT ); Tue, 4 Dec 2018 19:46:48 -0500 Received: from mga09.intel.com ([134.134.136.24]:24524 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725979AbeLEAqr (ORCPT ); Tue, 4 Dec 2018 19:46:47 -0500 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 04 Dec 2018 16:46:46 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,316,1539673200"; d="scan'208";a="299366323" Received: from jsakkine-mobl1.jf.intel.com (HELO localhost) ([10.24.8.183]) by fmsmga006.fm.intel.com with ESMTP; 04 Dec 2018 16:46:44 -0800 Date: Tue, 4 Dec 2018 16:46:43 -0800 From: Jarkko Sakkinen To: Roberto Sassu Cc: zohar@linux.ibm.com, david.safford@ge.com, monty.wiseman@ge.com, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, silviu.vlasceanu@huawei.com Subject: Re: [PATCH v6 6/7] tpm: ensure that the output of PCR read contains the correct digest size Message-ID: <20181205004643.GA26578@linux.intel.com> References: <20181204082138.24600-1-roberto.sassu@huawei.com> <20181204082138.24600-7-roberto.sassu@huawei.com> <20181205000910.GE1233@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181205000910.GE1233@linux.intel.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.10.1 (2018-07-13) Sender: owner-linux-security-module@vger.kernel.org Precedence: bulk List-ID: On Tue, Dec 04, 2018 at 04:09:10PM -0800, Jarkko Sakkinen wrote: > On Tue, Dec 04, 2018 at 09:21:37AM +0100, Roberto Sassu wrote: > > out = (struct tpm2_pcr_read_out *)&buf.data[TPM_HEADER_SIZE]; > > digest_size = be16_to_cpu(out->digest_size); > > - if (digest_size > sizeof(digest->digest)) { > > + if (digest_size > sizeof(digest->digest) || > > + (!digest_size_ptr && digest_size != expected_digest_size)) { > > rc = -EINVAL; > > goto out; > > } > > Just noticed this but you must squash 4-6 because applying only > previous commits will result a broken tree. It will be much bigger > commit but won't be broken. > > I think you should also feed min_rsp_body_length as you should be > able to precalculate. > > Last time I was asking why this isn't a bug fix. It is even for > the existing code. The existing code should have a bug fix that > checks that the received digest size so that it is the expected > SHA1 size before we can apply this commit. My bad. This is not the same deal as the code because in the old code we always copy a constant block. Here we use the variable as parameter for memcpy() so it is better to check the size. You can ignore the last paragraph completely. Sorry, had to double check this one. There is no need to do any type of bug fix for the current tree. Still 4-6 need to be squashed in order to not put purposely the tree into broken state. /Jarko