Re: [PATCH v11 00/16] Remove nested TPM operations

[Stefan Berger <stefanb@linux.ibm.com>]

On 2/7/19 4:29 PM, Jarkko Sakkinen wrote:
> On Thu, Feb 07, 2019 at 07:41:56PM +0100, Alexander Steffen wrote:
>> On 06.02.2019 13:06, Jarkko Sakkinen wrote:
>>> On Wed, Feb 06, 2019 at 12:47:07AM +0200, Jarkko Sakkinen wrote:
>>>> Make the changes necessary to detach TPM space code and TPM activation
>>>> code out of the tpm_transmit() flow because of both of these can cause
>>>> nested tpm_transmit() calls. The nesteds calls make the whole flow hard
>>>> to maintain, and thus, it is better to just fix things now before this
>>>> turns into a bigger mess.
>>>>
>>>> v11:
>>>> * Drop the patch that tries to flush TPM space on system. Not a proper
>>>>     fallback + out of scope for this patch set.
>>>>
>>>> v10:
>>>> * Use void pointers to avoid unnecessary casts in functions paramaters
>>>>     where it makes sense.
>>>>
>>>> v9:
>>>> * Fixed again tpm_try_get_ops().
>>>> * Added missing reviewed-by's.
>>>>
>>>> v8:
>>>> * Re-add the check for ret < 0 after calling tpm_try_transmit() that
>>>>     was dropped by mistake while moving code.
>>>> * Fix error fallback for tpm_try_get_ops() when tpm_chip_start()
>>>>     fails.
>>>>
>>>> v7:
>>>> *  Reorganize series so that more trivial and self-contained changes are
>>>>      in the head.
>>>>
>>>> v6:
>>>> * When tpm_validate_commmand() was moved to tpm2-space.c, the struct for
>>>>     the TPM header was incorrectly declared as struct tpm_input_header.
>>>> * Fix return value in tpm_validate_command().
>>>>
>>>> v5:
>>>> * Add the missing rev's from Stefan Berger.
>>>>
>>>> v4:
>>>> * Return 0 from pcrs_show() when tpm1_pcr_read() fails.
>>>> * Fix error handling flow in tpm_try_transmit().
>>>> * Replace struct tpm_input_header and struct tpm_output_header with
>>>>     struct tpm_header.
>>>>
>>>> v3:
>>>> * Encapsulate power gating code to tpm_chip_start() and tpm_chip_stop().
>>>> * Move TPM power gating code and locking to tpm_try_get_ops() and
>>>>     tpm_put_ops().
>>>> * Call power gating code directly in tpm_chip_register() and
>>>>     tpm2_del_space().
>>>>
>>>> v2:
>>>> * Print tpm2_commit_space() error inside tpm2_commit_space()
>>>> * Error code was not printed when recv() callback failed. It is
>>>>     fixed in this version.
>>>> * Added a patch that removes @space from tpm_transmit().
>>>> * Fixed a regression in earlier series. Forgot to amend the change
>>>>     from the staging area that renames NESTED to UNLOCKED in tpm2-space.c.
>>>>
>>>> Jarkko Sakkinen (16):
>>>>     tpm: use tpm_buf in tpm_transmit_cmd() as the IO parameter
>>>>     tpm: fix invalid return value in pubek_show()
>>>>     tpm: return 0 from pcrs_show() when tpm1_pcr_read() fails
>>>>     tpm: print tpm2_commit_space() error inside tpm2_commit_space()
>>>>     tpm: declare struct tpm_header
>>>>     tpm: access command header through struct in tpm_try_transmit()
>>>>     tpm: encapsulate tpm_dev_transmit()
>>>>     tpm: clean up tpm_try_transmit() error handling flow
>>>>     tpm: move tpm_validate_commmand() to tpm2-space.c
>>>>     tpm: move TPM space code out of tpm_transmit()
>>>>     tpm: remove @space from tpm_transmit()
>>>>     tpm: use tpm_try_get_ops() in tpm-sysfs.c.
>>>>     tpm: remove TPM_TRANSMIT_UNLOCKED flag
>>>>     tpm: introduce tpm_chip_start() and tpm_chip_stop()
>>>>     tpm: take TPM chip power gating out of tpm_transmit()
>>>>     tpm: remove @flags from tpm_transmit()
>>>>
>>>>    drivers/char/tpm/tpm-chip.c       | 109 ++++++++++++
>>>>    drivers/char/tpm/tpm-dev-common.c |  44 ++++-
>>>>    drivers/char/tpm/tpm-interface.c  | 264 ++++++------------------------
>>>>    drivers/char/tpm/tpm-sysfs.c      | 138 ++++++++++------
>>>>    drivers/char/tpm/tpm.h            |  64 +++-----
>>>>    drivers/char/tpm/tpm1-cmd.c       |  28 +---
>>>>    drivers/char/tpm/tpm2-cmd.c       |  72 +++-----
>>>>    drivers/char/tpm/tpm2-space.c     |  91 +++++++---
>>>>    drivers/char/tpm/tpm_i2c_atmel.c  |   5 +-
>>>>    drivers/char/tpm/tpm_vtpm_proxy.c |  12 +-
>>>>    drivers/char/tpm/xen-tpmfront.c   |   2 +-
>>>>    11 files changed, 408 insertions(+), 421 deletions(-)
>>>>
>>>> -- 
>>>> 2.19.1
>>>>
>>> Applied to master and next.
>> Something in this series seems to break basic TPM communication for me.
>>
>> For TPM2.0s the probe command fails, causing them to be misdetected as
>> TPM1.2s:
>>
>> ---
>> tpm tpm0: tpm_try_transmit: tpm_send: error -5
>> tpm_tis MSFT0101:00: 1.2 TPM (device-id 0x1A, rev-id 22)
>> tpm tpm0: A TPM error (30) occurred attempting to determine the timeouts
>> ---
>> tpm tpm0: tpm_try_transmit: tpm_send: error -5
>> tpm_tis_spi spi0.1: 1.2 TPM (device-id 0x1B, rev-id 22)
>> tpm tpm0: A TPM error (30) occurred attempting to determine the timeouts
>> ---
>>
>> And for something that actually is a TPM1.2 it fails in a similar way:
>>
>> ---
>> tpm_i2c_infineon 1-0020: 1.2 TPM (device-id 0x1A)
>> tpm tpm0: A TPM error (-14) occurred attempting to determine the timeouts
>> ---
>> tpm tpm0: tpm_try_transmit: tpm_send: error -5
>> tpm_tis_spi spi0.1: 1.2 TPM (device-id 0x1B, rev-id 16)
>> tpm tpm0: A TPM error (-14) occurred attempting to determine the timeouts
>> tpm_tis_spi: probe of spi0.1 failed with error -14
>> ---
>>
>> I see this problem across my entire range of TPM devices and test platforms.
>> Any idea what could be wrong here?
> Weird.
>
> Can you run a bisect?

There are 2 bugs and the following overall patch against your tree fixes 
them. Let me comment on the individual patches in v17. I missed those 
obviously when testing with the tpm_vtpm_proxy...



diff --git a/drivers/char/tpm/tpm-interface.c 
b/drivers/char/tpm/tpm-interface.c
index 02e8cffd1163..34c0da55d885 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -94,6 +94,7 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip, 
void *buf, size_t bufsiz)
          return rc;
      }

+    rc = 0;
      if (chip->flags & TPM_CHIP_FLAG_IRQ)
          goto out_recv;

diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c
index e74c5b7b64bf..52afe20cc8a1 100644
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -799,7 +799,9 @@ int tpm2_probe(struct tpm_chip *chip)
      tpm_buf_append_u32(&buf, TPM2_CAP_TPM_PROPERTIES);
      tpm_buf_append_u32(&buf, TPM_PT_TOTAL_COMMANDS);
      tpm_buf_append_u32(&buf, 1);
+    tpm_chip_start(chip);
      rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
+    tpm_chip_stop(chip);
      /* We ignore TPM return codes on purpose. */
      if (rc >=  0) {
          out = (struct tpm_header *)buf.data;

>
> /Jarkko
>