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=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 F03D9C43387 for ; Sat, 22 Dec 2018 00:03:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C69B121928 for ; Sat, 22 Dec 2018 00:03:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389027AbeLVAD2 (ORCPT ); Fri, 21 Dec 2018 19:03:28 -0500 Received: from mga02.intel.com ([134.134.136.20]:43372 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387468AbeLVAD2 (ORCPT ); Fri, 21 Dec 2018 19:03:28 -0500 X-Amp-Result: UNSCANNABLE X-Amp-File-Uploaded: False Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 21 Dec 2018 16:03:26 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,383,1539673200"; d="scan'208";a="120346172" Received: from ncanderx-mobl.ger.corp.intel.com (HELO localhost) ([10.249.254.238]) by FMSMGA003.fm.intel.com with ESMTP; 21 Dec 2018 16:03:22 -0800 Date: Sat, 22 Dec 2018 02:03:21 +0200 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 v7 1/5] tpm: dynamically allocate the allocated_banks array Message-ID: <20181222000321.GB8954@linux.intel.com> 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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <0900a894-e17b-edc8-fa30-db7d16665082@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: 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. /Jarkko