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=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 E0692C43444 for ; Mon, 7 Jan 2019 10:06:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BB0E420854 for ; Mon, 7 Jan 2019 10:06:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726703AbfAGKGs (ORCPT ); Mon, 7 Jan 2019 05:06:48 -0500 Received: from lhrrgout.huawei.com ([185.176.76.210]:32818 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726453AbfAGKGr (ORCPT ); Mon, 7 Jan 2019 05:06:47 -0500 Received: from LHREML711-CAH.china.huawei.com (unknown [172.18.7.106]) by Forcepoint Email with ESMTP id EC413F9CFFC653B95D1C; Mon, 7 Jan 2019 10:06:45 +0000 (GMT) Received: from [10.204.65.149] (10.204.65.149) by smtpsuk.huawei.com (10.201.108.34) with Microsoft SMTP Server (TLS) id 14.3.408.0; Mon, 7 Jan 2019 10:06:38 +0000 Subject: Re: [PATCH v7 1/5] tpm: dynamically allocate the allocated_banks array To: Jarkko Sakkinen CC: , , , , , , References: <20181213102945.30946-1-roberto.sassu@huawei.com> <20181213102945.30946-2-roberto.sassu@huawei.com> <20181220145500.GA10652@linux.intel.com> <0900a894-e17b-edc8-fa30-db7d16665082@huawei.com> <20181222000321.GB8954@linux.intel.com> From: Roberto Sassu Message-ID: <7cc91a22-b09b-8bdc-c225-adff68e1f69e@huawei.com> Date: Mon, 7 Jan 2019 11:06:33 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.3.0 MIME-Version: 1.0 In-Reply-To: <20181222000321.GB8954@linux.intel.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.204.65.149] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/22/2018 1:03 AM, Jarkko Sakkinen wrote: > On Fri, Dec 21, 2018 at 10:40:09AM +0100, Roberto Sassu wrote: >> On 12/20/2018 3:55 PM, Jarkko Sakkinen wrote: >>> On Thu, Dec 13, 2018 at 11:29:41AM +0100, Roberto Sassu wrote: >>>> This patch renames active_banks (member of tpm_chip) to allocated_banks, >>>> stores the number of allocated PCR banks in nr_allocated_banks (new member >>>> of tpm_chip), and replaces the static array with a pointer to a dynamically >>>> allocated array. >>>> >>>> tpm2_get_pcr_allocation() determines if a PCR bank is allocated by checking >>>> the mask in the TPML_PCR_SELECTION structure returned by the TPM for >>>> TPM2_Get_Capability(). If a bank is not allocated, the TPM returns that >>>> bank in TPML_PCR_SELECTION, with all bits in the mask set to zero. In this >>>> case, the bank is not included in chip->allocated_banks, to avoid that TPM >>>> driver users unnecessarily calculate a digest for that bank. >>>> >>>> One PCR bank with algorithm set to SHA1 is always allocated for TPM 1.x. >>>> >>>> As a consequence of the introduction of nr_allocated_banks, >>>> tpm_pcr_extend() does not check anymore if the algorithm stored in tpm_chip >>>> is equal to zero. >>>> >>>> Signed-off-by: Roberto Sassu >>>> Tested-by: Jarkko Sakkinen >>>> --- >>>> drivers/char/tpm/tpm-chip.c | 1 + >>>> drivers/char/tpm/tpm-interface.c | 18 +++++++++-------- >>>> drivers/char/tpm/tpm.h | 3 ++- >>>> drivers/char/tpm/tpm1-cmd.c | 10 ++++++++++ >>>> drivers/char/tpm/tpm2-cmd.c | 34 ++++++++++++++++++++++---------- >>>> 5 files changed, 47 insertions(+), 19 deletions(-) >>>> >>>> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c >>>> index 32db84683c40..ce851c62bb68 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->allocated_banks); >>>> kfree(chip); >>>> } >>>> diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c >>>> index d9439f9abe78..7b80919228be 100644 >>>> --- a/drivers/char/tpm/tpm-interface.c >>>> +++ b/drivers/char/tpm/tpm-interface.c >>>> @@ -488,8 +488,7 @@ EXPORT_SYMBOL_GPL(tpm_pcr_read); >>>> int tpm_pcr_extend(struct tpm_chip *chip, u32 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); >>>> @@ -497,16 +496,19 @@ int tpm_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash) >>>> return -ENODEV; >>>> if (chip->flags & TPM_CHIP_FLAG_TPM2) { >>>> - memset(digest_list, 0, sizeof(digest_list)); >>>> + digest_list = kcalloc(chip->nr_allocated_banks, >>>> + sizeof(*digest_list), GFP_KERNEL); >>>> + if (!digest_list) >>>> + return -ENOMEM; >>> >>> You could preallocate digest list and place it to struct tpm_chip >>> instead of doing it everytime tpm_pcr_extend() called. >> >> This part will be removed with patch 5/5. > > Even if it did, it does not make this patch unbroken. Can two calls to tpm_pcr_extend() be executed at the same time? If yes, the digest list should be protected by a mutex. Roberto > /Jarkko > -- HUAWEI TECHNOLOGIES Duesseldorf GmbH, HRB 56063 Managing Director: Bo PENG, Jian LI, Yanli SHI