From patchwork Thu Jun 25 04:38:16 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 11624635 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 397D290 for ; Thu, 25 Jun 2020 04:38:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1BEA120773 for ; Thu, 25 Jun 2020 04:38:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726914AbgFYEib (ORCPT ); Thu, 25 Jun 2020 00:38:31 -0400 Received: from mga17.intel.com ([192.55.52.151]:56775 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726400AbgFYEib (ORCPT ); Thu, 25 Jun 2020 00:38:31 -0400 IronPort-SDR: IQqcOYlNwHW+SNdfgY6No719yDpPM6k6HEHQXrXMM+IC0G+ewkzFPN0AD2/eN9zuz4I1+/C9qv ClQIOoSxnojQ== X-IronPort-AV: E=McAfee;i="6000,8403,9662"; a="124994916" X-IronPort-AV: E=Sophos;i="5.75,278,1589266800"; d="scan'208";a="124994916" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 24 Jun 2020 21:38:30 -0700 IronPort-SDR: rW/QrsxsaBFg9OVp1MNb5hUg5t6x3YkQiPCj0tHP5q2xY+PtkcjnpDLwF7TqLHp6cTEpjwCczq hjcK7Z1dubiw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,278,1589266800"; d="scan'208";a="265254035" Received: from skurzyno-mobl2.ger.corp.intel.com (HELO localhost) ([10.249.40.230]) by fmsmga008.fm.intel.com with ESMTP; 24 Jun 2020 21:38:25 -0700 From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: Jarkko Sakkinen , James Bottomley , Stefan Berger , Peter Huewe , Jason Gunthorpe , Arnd Bergmann , Greg Kroah-Hartman , Jerry Snitselaar , Sumit Garg , Alexey Klimov , linux-kernel@vger.kernel.org (open list) Subject: [PATCH v2] tpm: tpm2-space: Resize session and context buffers dynamically Date: Thu, 25 Jun 2020 07:38:16 +0300 Message-Id: <20200625043819.376693-1-jarkko.sakkinen@linux.intel.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org Re-allocate context and session buffers when needed. Scale them in page increments so that the reallocation is only seldomly required, and thus causes minimal stress to the system. Add a static maximum limit of four pages for buffer sizes. Cc: James Bottomley Suggested-by: Stefan Berger Signed-off-by: Jarkko Sakkinen --- Tested only for compilation. v2: TPM2_SPACE_DEFAULT_BUFFER_SIZE drivers/char/tpm/tpm2-space.c | 87 ++++++++++++++++++++++++----------- include/linux/tpm.h | 6 ++- 2 files changed, 64 insertions(+), 29 deletions(-) diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c index 982d341d8837..b8ece01d6afb 100644 --- a/drivers/char/tpm/tpm2-space.c +++ b/drivers/char/tpm/tpm2-space.c @@ -15,6 +15,9 @@ #include #include "tpm.h" +#define TPM2_SPACE_DEFAULT_BUFFER_SIZE PAGE_SIZE +#define TPM2_SPACE_MAX_BUFFER_SIZE (4 * PAGE_SIZE) + enum tpm2_handle_types { TPM2_HT_HMAC_SESSION = 0x02000000, TPM2_HT_POLICY_SESSION = 0x03000000, @@ -40,16 +43,21 @@ static void tpm2_flush_sessions(struct tpm_chip *chip, struct tpm_space *space) int tpm2_init_space(struct tpm_space *space) { - space->context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL); + space->context_buf = kzalloc(TPM2_SPACE_DEFAULT_BUFFER_SIZE, + GFP_KERNEL); if (!space->context_buf) return -ENOMEM; - space->session_buf = kzalloc(PAGE_SIZE, GFP_KERNEL); + space->session_buf = kzalloc(TPM2_SPACE_DEFAULT_BUFFER_SIZE, + GFP_KERNEL); if (space->session_buf == NULL) { kfree(space->context_buf); + space->context_buf = NULL; return -ENOMEM; } + space->context_size = TPM2_SPACE_DEFAULT_BUFFER_SIZE; + space->session_size = TPM2_SPACE_DEFAULT_BUFFER_SIZE; return 0; } @@ -116,11 +124,13 @@ static int tpm2_load_context(struct tpm_chip *chip, u8 *buf, return 0; } -static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf, - unsigned int buf_size, unsigned int *offset) +static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 **buf, + unsigned int *buf_size, unsigned int *offset) { - struct tpm_buf tbuf; + unsigned int new_buf_size; unsigned int body_size; + struct tpm_buf tbuf; + void *new_buf; int rc; rc = tpm_buf_init(&tbuf, TPM2_ST_NO_SESSIONS, TPM2_CC_CONTEXT_SAVE); @@ -131,31 +141,48 @@ static int tpm2_save_context(struct tpm_chip *chip, u32 handle, u8 *buf, rc = tpm_transmit_cmd(chip, &tbuf, 0, NULL); if (rc < 0) { - dev_warn(&chip->dev, "%s: failed with a system error %d\n", - __func__, rc); - tpm_buf_destroy(&tbuf); - return -EFAULT; + rc = -EFAULT; + goto err; } else if (tpm2_rc_value(rc) == TPM2_RC_REFERENCE_H0) { - tpm_buf_destroy(&tbuf); - return -ENOENT; + rc = -ENOENT; + goto out; } else if (rc) { - dev_warn(&chip->dev, "%s: failed with a TPM error 0x%04X\n", - __func__, rc); - tpm_buf_destroy(&tbuf); - return -EFAULT; + rc = -EFAULT; + goto err; } body_size = tpm_buf_length(&tbuf) - TPM_HEADER_SIZE; - if ((*offset + body_size) > buf_size) { - dev_warn(&chip->dev, "%s: out of backing storage\n", __func__); - tpm_buf_destroy(&tbuf); - return -ENOMEM; + /* We grow the buffer in page increments. */ + new_buf_size = PFN_UP(*offset + body_size); + + if (new_buf_size > TPM2_SPACE_MAX_BUFFER_SIZE) { + rc = -ENOMEM; + goto err; } - memcpy(&buf[*offset], &tbuf.data[TPM_HEADER_SIZE], body_size); + if (new_buf_size > *buf_size) { + new_buf = krealloc(*buf, new_buf_size, GFP_KERNEL); + if (!new_buf) { + rc = -ENOMEM; + goto err; + } + + *buf = new_buf; + *buf_size = new_buf_size; + } + + memcpy(*buf + *offset, &tbuf.data[TPM_HEADER_SIZE], body_size); *offset += body_size; + +out: tpm_buf_destroy(&tbuf); - return 0; + return rc; + +err: + dev_warn(&chip->dev, "%s: ret=%d\n", __func__, rc); + + tpm_buf_destroy(&tbuf); + return rc; } void tpm2_flush_space(struct tpm_chip *chip) @@ -311,8 +338,10 @@ int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u8 *cmd, sizeof(space->context_tbl)); memcpy(&chip->work_space.session_tbl, &space->session_tbl, sizeof(space->session_tbl)); - memcpy(chip->work_space.context_buf, space->context_buf, PAGE_SIZE); - memcpy(chip->work_space.session_buf, space->session_buf, PAGE_SIZE); + memcpy(chip->work_space.context_buf, space->context_buf, + space->context_size); + memcpy(chip->work_space.session_buf, space->session_buf, + space->session_size); rc = tpm2_load_space(chip); if (rc) { @@ -492,7 +521,8 @@ static int tpm2_save_space(struct tpm_chip *chip) continue; rc = tpm2_save_context(chip, space->context_tbl[i], - space->context_buf, PAGE_SIZE, + &space->context_buf, + &space->context_size, &offset); if (rc == -ENOENT) { space->context_tbl[i] = 0; @@ -509,7 +539,8 @@ static int tpm2_save_space(struct tpm_chip *chip) continue; rc = tpm2_save_context(chip, space->session_tbl[i], - space->session_buf, PAGE_SIZE, + &space->session_buf, + &space->session_size, &offset); if (rc == -ENOENT) { @@ -557,8 +588,10 @@ int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space, sizeof(space->context_tbl)); memcpy(&space->session_tbl, &chip->work_space.session_tbl, sizeof(space->session_tbl)); - memcpy(space->context_buf, chip->work_space.context_buf, PAGE_SIZE); - memcpy(space->session_buf, chip->work_space.session_buf, PAGE_SIZE); + memcpy(space->context_buf, chip->work_space.context_buf, + space->context_size); + memcpy(space->session_buf, chip->work_space.session_buf, + space->session_size); return 0; out: diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 03e9b184411b..9ea39e8f7162 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -92,10 +92,12 @@ enum tpm_duration { #define TPM_PPI_VERSION_LEN 3 struct tpm_space { + u8 *context_buf; + u8 *session_buf; + u32 context_size; + u32 session_size; u32 context_tbl[3]; - u8 *context_buf; u32 session_tbl[3]; - u8 *session_buf; }; struct tpm_bios_log {