lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Tue, 31 Mar 2020 14:32:04 +0300
From:   <amirmizi6@...il.com>
To:     <Eyal.Cohen@...oton.com>, <jarkko.sakkinen@...ux.intel.com>,
        <oshrialkoby85@...il.com>, <alexander.steffen@...ineon.com>,
        <robh+dt@...nel.org>, <mark.rutland@....com>, <peterhuewe@....de>,
        <jgg@...pe.ca>, <arnd@...db.de>, <gregkh@...uxfoundation.org>
CC:     <devicetree@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        <linux-integrity@...r.kernel.org>, <oshri.alkoby@...oton.com>,
        <tmaimon77@...il.com>, <gcwilson@...ibm.com>,
        <kgoldman@...ibm.com>, <Dan.Morav@...oton.com>,
        <oren.tanami@...oton.com>, <shmulik.hager@...oton.com>,
        <amir.mizinski@...oton.com>, Amir Mizinski <amirmizi6@...il.com>
Subject: [PATCH v4 4/7] tpm: tpm_tis: Fix expected bit handling and send all bytes in one shot without last byte in exception

From: Amir Mizinski <amirmizi6@...il.com>

Today, actual implementation for send massage is not correct. We check and
loop only on TPM_STS.stsValid bit and next we single check TPM_STS.expect
bit value.
TPM_STS.expected bit shall be checked in the same time of
TPM_STS.stsValid, and should be repeated until timeout_A.
To aquire that, "wait_for_tpm_stat" function is modified to
"wait_for_tpm_stat_result". this function read regulary status register
and check bit defined by "mask" to reach value defined in "mask_result"
(that way a bit in mask can be checked if reached 1 or 0).

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.

This improvment was suggested by Benoit Houyere.

Signed-off-by: Amir Mizinski <amirmizi6@...il.com>
---
 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 18b9dc4..c8f4cf8 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_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;
-       }

        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;
                }
--
2.7.4



===========================================================================================
The privileged confidential information contained in this email is intended for use only by the addressees as indicated by the original sender of this email. If you are not the addressee indicated in this email or are not responsible for delivery of the email to such a person, please kindly reply to the sender indicating this fact and delete all copies of it from your computer and network server immediately. Your cooperation is highly appreciated. It is advised that any unauthorized use of confidential information of Nuvoton is strictly prohibited; and any information in this email irrelevant to the official business of Nuvoton shall be deemed as neither given nor endorsed by Nuvoton.

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ