From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752133AbdASKsE (ORCPT ); Thu, 19 Jan 2017 05:48:04 -0500 Received: from mga14.intel.com ([192.55.52.115]:23359 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751525AbdASKsC (ORCPT ); Thu, 19 Jan 2017 05:48:02 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.33,253,1477983600"; d="scan'208";a="1114926144" Date: Thu, 19 Jan 2017 12:47:59 +0200 From: Jarkko Sakkinen To: Nayna Cc: tpmdd-devel@lists.sourceforge.net, peterhuewe@gmx.de, tpmdd@selhorst.net, jgunthorpe@obsidianresearch.com, linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 1/2] tpm: implement TPM 2.0 capability to get active PCR banks Message-ID: <20170119104759.oqobziiuy7lqnzbf@intel.com> References: <1484729090-16012-1-git-send-email-nayna@linux.vnet.ibm.com> <1484729090-16012-2-git-send-email-nayna@linux.vnet.ibm.com> <20170118134522.ftikno7gy3vttv6w@intel.com> <587F7252.4070808@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <587F7252.4070808@linux.vnet.ibm.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo User-Agent: Mutt/1.6.2-neo (2016-08-21) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 18, 2017 at 07:19:06PM +0530, Nayna wrote: > > > On 01/18/2017 07:15 PM, Jarkko Sakkinen wrote: > > On Wed, Jan 18, 2017 at 03:44:49AM -0500, Nayna Jain wrote: > > > This patch implements the TPM 2.0 capability TPM_CAP_PCRS to > > > retrieve the active PCR banks from the TPM. This is needed > > > to enable extending all active banks as recommended by TPM 2.0 > > > TCG Specification. > > > > > > Signed-off-by: Nayna Jain > > > --- > > > drivers/char/tpm/tpm.h | 4 ++++ > > > drivers/char/tpm/tpm2-cmd.c | 57 +++++++++++++++++++++++++++++++++++++++++++++ > > > 2 files changed, 61 insertions(+) > > > > > > diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h > > > index 1ae9768..dddd573 100644 > > > --- a/drivers/char/tpm/tpm.h > > > +++ b/drivers/char/tpm/tpm.h > > > @@ -127,6 +127,7 @@ enum tpm2_permanent_handles { > > > }; > > > > > > enum tpm2_capabilities { > > > + TPM2_CAP_PCRS = 5, > > > TPM2_CAP_TPM_PROPERTIES = 6, > > > }; > > > > > > @@ -187,6 +188,8 @@ struct tpm_chip { > > > > > > const struct attribute_group *groups[3]; > > > unsigned int groups_cnt; > > > + > > > + u16 active_banks[7]; > > > #ifdef CONFIG_ACPI > > > acpi_handle acpi_dev_handle; > > > char ppi_version[TPM_PPI_VERSION_LEN + 1]; > > > @@ -545,4 +548,5 @@ int tpm2_auto_startup(struct tpm_chip *chip); > > > void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type); > > > unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal); > > > int tpm2_probe(struct tpm_chip *chip); > > > +ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip); > > > #endif > > > diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c > > > index 6eda239..75a7546 100644 > > > --- a/drivers/char/tpm/tpm2-cmd.c > > > +++ b/drivers/char/tpm/tpm2-cmd.c > > > @@ -998,3 +998,60 @@ int tpm2_auto_startup(struct tpm_chip *chip) > > > rc = -ENODEV; > > > return rc; > > > } > > > + > > > +struct tpm2_pcr_selection { > > > + __be16 hash_alg; > > > + u8 size_of_select; > > > + u8 pcr_select[3]; > > > +} __packed; > > > + > > > +/** > > > + * tpm2_get_pcr_allocation() - get TPM active PCR banks. > > > + * > > > + * @chip: TPM chip to use. > > > + * > > > + * Return: Same as with tpm_transmit_cmd. > > > + */ > > > +ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) > > > +{ > > > + struct tpm2_pcr_selection pcr_selection; > > > + struct tpm_buf buf; > > > + void *marker; > > > + unsigned int count = 0; > > > > You shouldn't initialize 'count'. > > It is initialized for reason below: > > > > > > + int rc; > > > + int i; > > > + > > > + rc = tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_GET_CAPABILITY); > > > + if (rc) > > > + return rc; > > > + > > > + tpm_buf_append_u32(&buf, TPM2_CAP_PCRS); > > > + tpm_buf_append_u32(&buf, 0); > > > + tpm_buf_append_u32(&buf, 1); > > > + > > > + rc = tpm_transmit_cmd(chip, buf.data, PAGE_SIZE, 0, > > > + "get tpm pcr allocation"); > > > + if (rc < 0) > > > + goto out; > > if tpm_transmit_cmd()fails, it jumps to out: > where count is used in if(..). Why the out label is placed there and not after? > > Thanks & Regards, > - Nayna > > > > + > > > + count = be32_to_cpup( > > > + (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]); > > > + > > > + if (count > ARRAY_SIZE(chip->active_banks)) > > > + return -ENODEV; Hey, here's a regression (didn't notice it last time). You nee to call tpm_buf_destroy(). > > > + > > > + marker = &buf.data[TPM_HEADER_SIZE + 9]; > > > + for (i = 0; i < count; i++) { > > > + memcpy(&pcr_selection, marker, sizeof(pcr_selection)); > > > + chip->active_banks[i] = be16_to_cpu(pcr_selection.hash_alg); > > > + marker = marker + sizeof(struct tpm2_pcr_selection); > > > + } > > > + > > > +out: > > > + if (count < ARRAY_SIZE(chip->active_banks)) > > > + chip->active_banks[count] = 0; > > > + > > > + tpm_buf_destroy(&buf); > > > + > > > + return rc; > > > +} > > > -- > > > 2.5.0 > > > > Otherwise, > > > > Reviewed-by: Jarkko Sakkinen > > > > /Jarkko > > > /Jarkko