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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 4589BECDE4B for ; Thu, 8 Nov 2018 13:47:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0C6F720825 for ; Thu, 8 Nov 2018 13:47:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0C6F720825 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 S1727062AbeKHXWb (ORCPT ); Thu, 8 Nov 2018 18:22:31 -0500 Received: from mga05.intel.com ([192.55.52.43]:22951 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726359AbeKHXWa (ORCPT ); Thu, 8 Nov 2018 18:22:30 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga105.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Nov 2018 05:46:57 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.54,478,1534834800"; d="scan'208";a="272413498" Received: from ibanaga-mobl1.ger.corp.intel.com (HELO localhost) ([10.249.254.75]) by orsmga005.jf.intel.com with ESMTP; 08 Nov 2018 05:46:53 -0800 Date: Thu, 8 Nov 2018 15:46:51 +0200 From: Jarkko Sakkinen To: Roberto Sassu Cc: zohar@linux.ibm.com, linux-integrity@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, silviu.vlasceanu@huawei.com Subject: Re: [PATCH v4 1/6] tpm: dynamically allocate active_banks array Message-ID: <20181108134651.GA8922@linux.intel.com> References: <20181106150159.1136-1-roberto.sassu@huawei.com> <20181106150159.1136-2-roberto.sassu@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181106150159.1136-2-roberto.sassu@huawei.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: Orrayn Tue, Nov 06, 2018 at 04:01:54PM +0100, Roberto Sassu wrote: > This patch removes the hard-coded limit of the active_banks array size. > It stores in the tpm_chip structure the number of active PCR banks, > determined in tpm2_get_pcr_allocation(), and replaces the static array > with a pointer to a dynamically allocated array. > > As a consequence of the introduction of nr_active_banks, tpm_pcr_extend() > does not check anymore if the algorithm stored in tpm_chip is equal to > zero. The active_banks array always contains valid algorithms. > > Fixes: 1db15344f874 ("tpm: implement TPM 2.0 capability to get active > PCR banks") > > Signed-off-by: Roberto Sassu > --- > drivers/char/tpm/tpm-chip.c | 1 + > drivers/char/tpm/tpm-interface.c | 19 ++++++++++++------- > drivers/char/tpm/tpm.h | 3 ++- > drivers/char/tpm/tpm2-cmd.c | 17 ++++++++--------- > 4 files changed, 23 insertions(+), 17 deletions(-) > > diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c > index 46caadca916a..2a9e8b744436 100644 > --- a/drivers/char/tpm/tpm-chip.c > +++ b/drivers/char/tpm/tpm-chip.c > @@ -160,6 +160,7 @@ static void tpm_dev_release(struct device *dev) > kfree(chip->log.bios_event_log); > kfree(chip->work_space.context_buf); > kfree(chip->work_space.session_buf); > + kfree(chip->active_banks); > kfree(chip); > } > > diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c > index 1a803b0cf980..ba7ca6b3e664 100644 > --- a/drivers/char/tpm/tpm-interface.c > +++ b/drivers/char/tpm/tpm-interface.c > @@ -1039,8 +1039,7 @@ static int tpm1_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash, > int tpm_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash) > { > int rc; > - struct tpm2_digest digest_list[ARRAY_SIZE(chip->active_banks)]; > - u32 count = 0; > + struct tpm2_digest *digest_list; > int i; > > chip = tpm_find_get_ops(chip); > @@ -1048,16 +1047,22 @@ int tpm_pcr_extend(struct tpm_chip *chip, int pcr_idx, const u8 *hash) > return -ENODEV; Should take digest_list as input. Probably callers could re-use the same digest_list array multiple times? Move struct tpm_chip to include/linux/tpm.h so that the caller can query nr_active_banks and active_banks and can create the digest array by itself. Lets do this right at once now that this is being restructured. > > if (chip->flags & TPM_CHIP_FLAG_TPM2) { > - memset(digest_list, 0, sizeof(digest_list)); > + digest_list = kmalloc_array(chip->nr_active_banks, > + sizeof(*digest_list), GFP_KERNEL); > + if (!digest_list) > + return -ENOMEM; > > - for (i = 0; i < ARRAY_SIZE(chip->active_banks) && > - chip->active_banks[i] != TPM2_ALG_ERROR; i++) { > + memset(digest_list, 0, > + chip->nr_active_banks * sizeof(*digest_list)); You should use kcalloc() to allocate digest_list. > + > + for (i = 0; i < chip->nr_active_banks; i++) { > digest_list[i].alg_id = chip->active_banks[i]; > memcpy(digest_list[i].digest, hash, TPM_DIGEST_SIZE); > - count++; > } > > - rc = tpm2_pcr_extend(chip, pcr_idx, count, digest_list); > + rc = tpm2_pcr_extend(chip, pcr_idx, chip->nr_active_banks, > + digest_list); > + kfree(digest_list); > tpm_put_ops(chip); > return rc; > } > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h > index f3501d05264f..98368c3a6ff7 100644 > --- a/drivers/char/tpm/tpm.h > +++ b/drivers/char/tpm/tpm.h > @@ -248,7 +248,8 @@ struct tpm_chip { > const struct attribute_group *groups[3]; > unsigned int groups_cnt; > > - u16 active_banks[7]; > + u32 nr_active_banks; > + u16 *active_banks; > #ifdef CONFIG_ACPI > acpi_handle acpi_dev_handle; > char ppi_version[TPM_PPI_VERSION_LEN + 1]; > diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c > index c31b490bd41d..533089cede07 100644 > --- a/drivers/char/tpm/tpm2-cmd.c > +++ b/drivers/char/tpm/tpm2-cmd.c > @@ -242,7 +242,7 @@ int tpm2_pcr_extend(struct tpm_chip *chip, int pcr_idx, u32 count, > int i; > int j; > > - if (count > ARRAY_SIZE(chip->active_banks)) > + if (count > chip->nr_active_banks) > return -EINVAL; > > rc = tpm_buf_init(&buf, TPM2_ST_SESSIONS, TPM2_CC_PCR_EXTEND); > @@ -859,7 +859,6 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) > void *marker; > void *end; > void *pcr_select_offset; > - unsigned int count; > u32 sizeof_pcr_selection; > u32 rsp_len; > int rc; > @@ -878,11 +877,14 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) > if (rc) > goto out; > > - count = be32_to_cpup( > + chip->nr_active_banks = be32_to_cpup( > (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]); > > - if (count > ARRAY_SIZE(chip->active_banks)) { > - rc = -ENODEV; > + chip->active_banks = kmalloc_array(chip->nr_active_banks, > + sizeof(*chip->active_banks), > + GFP_KERNEL); > + if (!chip->active_banks) { > + rc = -ENOMEM; > goto out; > } > > @@ -891,7 +893,7 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) > rsp_len = be32_to_cpup((__be32 *)&buf.data[2]); > end = &buf.data[rsp_len]; > > - for (i = 0; i < count; i++) { > + for (i = 0; i < chip->nr_active_banks; i++) { > pcr_select_offset = marker + > offsetof(struct tpm2_pcr_selection, size_of_select); > if (pcr_select_offset >= end) { > @@ -908,9 +910,6 @@ static ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) > } > > out: > - if (i < ARRAY_SIZE(chip->active_banks)) > - chip->active_banks[i] = TPM2_ALG_ERROR; > - > tpm_buf_destroy(&buf); > > return rc; > -- > 2.17.1 > /Jarkko