From patchwork Tue Apr 7 16:20:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Amir Mizinski X-Patchwork-Id: 11478391 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 198F2174A for ; Tue, 7 Apr 2020 16:21:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0213320730 for ; Tue, 7 Apr 2020 16:21:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728229AbgDGQVc (ORCPT ); Tue, 7 Apr 2020 12:21:32 -0400 Received: from 212.199.177.27.static.012.net.il ([212.199.177.27]:40602 "EHLO herzl.nuvoton.co.il" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726637AbgDGQV1 (ORCPT ); Tue, 7 Apr 2020 12:21:27 -0400 Received: from taln60.nuvoton.co.il (ntil-fw [212.199.177.25]) by herzl.nuvoton.co.il (8.13.8/8.13.8) with ESMTP id 037GKtrw002272; Tue, 7 Apr 2020 19:20:55 +0300 Received: by taln60.nuvoton.co.il (Postfix, from userid 10140) id B221E639B0; Tue, 7 Apr 2020 19:20:55 +0300 (IDT) From: amirmizi6@gmail.com To: Eyal.Cohen@nuvoton.com, jarkko.sakkinen@linux.intel.com, oshrialkoby85@gmail.com, alexander.steffen@infineon.com, robh+dt@kernel.org, mark.rutland@arm.com, peterhuewe@gmx.de, jgg@ziepe.ca, arnd@arndb.de, gregkh@linuxfoundation.org Cc: devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-integrity@vger.kernel.org, oshri.alkoby@nuvoton.com, tmaimon77@gmail.com, gcwilson@us.ibm.com, kgoldman@us.ibm.com, Dan.Morav@nuvoton.com, oren.tanami@nuvoton.com, shmulik.hager@nuvoton.com, amir.mizinski@nuvoton.com, Amir Mizinski , Benoit Houyere Subject: [PATCH v6 4/7] tpm: tpm_tis: Fix expected bit handling and send all bytes in one shot without last byte in exception Date: Tue, 7 Apr 2020 19:20:41 +0300 Message-Id: <20200407162044.168890-5-amirmizi6@gmail.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20200407162044.168890-1-amirmizi6@gmail.com> References: <20200407162044.168890-1-amirmizi6@gmail.com> MIME-Version: 1.0 Sender: linux-integrity-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-integrity@vger.kernel.org From: Amir Mizinski Incorrect implementation to send message has been detected. We check and loop only on TPM_STS.stsValid bit and next we single check TPM_STS.expect bit value. TPM_STS.expected bit should be checked in the same time of TPM_STS.stsValid, and shall be repeated until timeout_A. To detect TPM_STS.expected bit reset "wait_for_tpm_stat" function is modified to "wait_for_tpm_stat_result". This function read regularly status register and check bit defined by "mask" to reach value defined in "mask_result". This correct implementation is mandatory to use new CRC calculation on I2C TPM command bytes or I2C TPM answer bytes. TPM_STS.expected bit is reset after all bytes acquired and CRC result inserted in dedicated register. It introduces a normal latency to have TPM_STS.expected bit reset. Respectively, to send message as defined in TCG_DesignPrinciples_TPM2p0Driver_vp24_pubrev.pdf, all bytes should be sent in one shot instead of sending last byte in exception. Suggested-by: Benoit Houyere Signed-off-by: Amir Mizinski --- drivers/char/tpm/tpm_tis_core.c | 72 ++++++++++++++++------------------------- 1 file changed, 28 insertions(+), 44 deletions(-) diff --git a/drivers/char/tpm/tpm_tis_core.c b/drivers/char/tpm/tpm_tis_core.c index 453d7ef..0a340c0 100644 --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -44,9 +44,10 @@ static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask, return false; } -static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, - unsigned long timeout, wait_queue_head_t *queue, - bool check_cancel) +static int wait_for_tpm_stat_result(struct tpm_chip *chip, u8 mask, + u8 mask_result, unsigned long timeout, + wait_queue_head_t *queue, + bool check_cancel) { unsigned long stop; long rc; @@ -55,7 +56,7 @@ static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, /* check current status */ status = chip->ops->status(chip); - if ((status & mask) == mask) + if ((status & mask) == mask_result) return 0; stop = jiffies + timeout; @@ -83,7 +84,7 @@ static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask, usleep_range(TPM_TIMEOUT_USECS_MIN, TPM_TIMEOUT_USECS_MAX); status = chip->ops->status(chip); - if ((status & mask) == mask) + if ((status & mask) == mask_result) return 0; } while (time_before(jiffies, stop)); } @@ -290,10 +291,11 @@ static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count) int size = 0, burstcnt, rc; while (size < count) { - rc = wait_for_tpm_stat(chip, - TPM_STS_DATA_AVAIL | TPM_STS_VALID, - chip->timeout_c, - &priv->read_queue, true); + rc = wait_for_tpm_stat_result(chip, + TPM_STS_DATA_AVAIL | TPM_STS_VALID, + TPM_STS_DATA_AVAIL | TPM_STS_VALID, + chip->timeout_c, + &priv->read_queue, true); if (rc < 0) return rc; burstcnt = get_burstcount(chip); @@ -348,8 +350,9 @@ static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count) goto out; } - if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, - &priv->int_queue, false) < 0) { + if (wait_for_tpm_stat_result(chip, TPM_STS_VALID, + TPM_STS_VALID, chip->timeout_c, + &priv->int_queue, false) < 0) { size = -ETIME; goto out; } @@ -385,61 +388,40 @@ static int tpm_tis_send_data(struct tpm_chip *chip, const u8 *buf, size_t len) struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev); int rc, status, burstcnt; size_t count = 0; - bool itpm = priv->flags & TPM_TIS_ITPM_WORKAROUND; status = tpm_tis_status(chip); if ((status & TPM_STS_COMMAND_READY) == 0) { tpm_tis_ready(chip); - if (wait_for_tpm_stat - (chip, TPM_STS_COMMAND_READY, chip->timeout_b, - &priv->int_queue, false) < 0) { + if (wait_for_tpm_stat_result(chip, TPM_STS_COMMAND_READY, + TPM_STS_COMMAND_READY, + chip->timeout_b, + &priv->int_queue, false) < 0) { rc = -ETIME; goto out_err; } } - while (count < len - 1) { + while (count < len) { burstcnt = get_burstcount(chip); if (burstcnt < 0) { dev_err(&chip->dev, "Unable to read burstcount\n"); rc = burstcnt; goto out_err; } - burstcnt = min_t(int, burstcnt, len - count - 1); + burstcnt = min_t(int, burstcnt, len - count); rc = tpm_tis_write_bytes(priv, TPM_DATA_FIFO(priv->locality), burstcnt, buf + count); if (rc < 0) goto out_err; count += burstcnt; - - if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, - &priv->int_queue, false) < 0) { - rc = -ETIME; - goto out_err; - } - status = tpm_tis_status(chip); - if (!itpm && (status & TPM_STS_DATA_EXPECT) == 0) { - rc = -EIO; - goto out_err; - } } - - /* write last byte */ - rc = tpm_tis_write8(priv, TPM_DATA_FIFO(priv->locality), buf[count]); - if (rc < 0) - goto out_err; - - if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c, - &priv->int_queue, false) < 0) { + if (wait_for_tpm_stat_result(chip, TPM_STS_VALID | TPM_STS_DATA_EXPECT, + TPM_STS_VALID, chip->timeout_a, + &priv->int_queue, false) < 0) { rc = -ETIME; goto out_err; } - status = tpm_tis_status(chip); - if (!itpm && (status & TPM_STS_DATA_EXPECT) != 0) { - rc = -EIO; - goto out_err; - } return 0; @@ -496,9 +478,11 @@ static int tpm_tis_send_main(struct tpm_chip *chip, const u8 *buf, size_t len) ordinal = be32_to_cpu(*((__be32 *) (buf + 6))); dur = tpm_calc_ordinal_duration(chip, ordinal); - if (wait_for_tpm_stat - (chip, TPM_STS_DATA_AVAIL | TPM_STS_VALID, dur, - &priv->read_queue, false) < 0) { + if (wait_for_tpm_stat_result(chip, + TPM_STS_DATA_AVAIL | TPM_STS_VALID, + TPM_STS_DATA_AVAIL | TPM_STS_VALID, + dur, + &priv->read_queue, false) < 0) { rc = -ETIME; goto out_err; }