linux-stable.git/include/linux/tpm.h, branch v5.15.208

tpm: Cap the number of PCR banks

2026-01-19T12:10:06+00:00

[ Upstream commit faf07e611dfa464b201223a7253e9dc5ee0f3c9e ]

tpm2_get_pcr_allocation() does not cap any upper limit for the number of
banks. Cap the limit to eight banks so that out of bounds values coming
from external I/O cause on only limited harm.

Cc: stable@vger.kernel.org # v5.10+
Fixes: bcfff8384f6c ("tpm: dynamically allocate the allocated_banks array")
Tested-by: Lai Yi 
Reviewed-by: Jonathan McDowell 
Reviewed-by: Roberto Sassu 
Signed-off-by: Jarkko Sakkinen 
[ added backward-compatible define for TPM_MAX_DIGEST_SIZE to support older ima_init.c code still using that macro name ]
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

tpm: tis: Double the timeout B to 4s

2025-06-04T12:38:08+00:00

[ Upstream commit 2f661f71fda1fc0c42b7746ca5b7da529eb6b5be ]

With some Infineon chips the timeouts in tpm_tis_send_data (both B and
C) can reach up to about 2250 ms.

Timeout C is retried since
commit de9e33df7762 ("tpm, tpm_tis: Workaround failed command reception on Infineon devices")

Timeout B still needs to be extended.

The problem is most commonly encountered with context related operation
such as load context/save context. These are issued directly by the
kernel, and there is no retry logic for them.

When a filesystem is set up to use the TPM for unlocking the boot fails,
and restarting the userspace service is ineffective. This is likely
because ignoring a load context/save context result puts the real TPM
state and the TPM state expected by the kernel out of sync.

Chips known to be affected:
tpm_tis IFX1522:00: 2.0 TPM (device-id 0x1D, rev-id 54)
Description: SLB9672
Firmware Revision: 15.22

tpm_tis MSFT0101:00: 2.0 TPM (device-id 0x1B, rev-id 22)
Firmware Revision: 7.83

tpm_tis MSFT0101:00: 2.0 TPM (device-id 0x1A, rev-id 16)
Firmware Revision: 5.63

Link: https://lore.kernel.org/linux-integrity/Z5pI07m0Muapyu9w@kitsune.suse.cz/
Signed-off-by: Michal Suchanek 
Reviewed-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen 
Signed-off-by: Sasha Levin

tpm: fix Atmel TPM crash caused by too frequent queries

2021-11-18T18:16:41+00:00

[ Upstream commit 79ca6f74dae067681a779fd573c2eb59649989bc ]

The Atmel TPM 1.2 chips crash with error
`tpm_try_transmit: send(): error -62` since kernel 4.14.
It is observed from the kernel log after running `tpm_sealdata -z`.
The error thrown from the command is as follows
```
$ tpm_sealdata -z
Tspi_Key_LoadKey failed: 0x00001087 - layer=tddl,
code=0087 (135), I/O error
```

The issue was reproduced with the following Atmel TPM chip:
```
$ tpm_version
T0  TPM 1.2 Version Info:
  Chip Version:        1.2.66.1
  Spec Level:          2
  Errata Revision:     3
  TPM Vendor ID:       ATML
  TPM Version:         01010000
  Manufacturer Info:   41544d4c
```

The root cause of the issue is due to the TPM calls to msleep()
were replaced with usleep_range() [1], which reduces
the actual timeout. Via experiments, it is observed that
the original msleep(5) actually sleeps for 15ms.
Because of a known timeout issue in Atmel TPM 1.2 chip,
the shorter timeout than 15ms can cause the error described above.

A few further changes in kernel 4.16 [2] and 4.18 [3, 4] further
reduced the timeout to less than 1ms. With experiments,
the problematic timeout in the latest kernel is the one
for `wait_for_tpm_stat`.

To fix it, the patch reverts the timeout of `wait_for_tpm_stat`
to 15ms for all Atmel TPM 1.2 chips, but leave it untouched
for Ateml TPM 2.0 chip, and chips from other vendors.
As explained above, the chosen 15ms timeout is
the actual timeout before this issue introduced,
thus the old value is used here.
Particularly, TPM_ATML_TIMEOUT_WAIT_STAT_MIN is set to 14700us,
TPM_ATML_TIMEOUT_WAIT_STAT_MIN is set to 15000us according to
the existing TPM_TIMEOUT_RANGE_US (300us).
The fixed has been tested in the system with the affected Atmel chip
with no issues observed after boot up.

References:
[1] 9f3fc7bcddcb tpm: replace msleep() with usleep_range() in TPM
1.2/2.0 generic drivers
[2] cf151a9a44d5 tpm: reduce tpm polling delay in tpm_tis_core
[3] 59f5a6b07f64 tpm: reduce poll sleep time in tpm_transmit()
[4] 424eaf910c32 tpm: reduce polling time to usecs for even finer
granularity

Fixes: 9f3fc7bcddcb ("tpm: replace msleep() with usleep_range() in TPM 1.2/2.0 generic drivers")
Link: https://patchwork.kernel.org/project/linux-integrity/patch/20200926223150.109645-1-hao.wu@rubrik.com/
Signed-off-by: Hao Wu 
Reviewed-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen 
Signed-off-by: Sasha Levin

security: keys: trusted: Make sealed key properly interoperable

2021-04-14T13:30:30+00:00

The current implementation appends a migratable flag to the end of a
key, meaning the format isn't exactly interoperable because the using
party needs to know to strip this extra byte.  However, all other
consumers of TPM sealed blobs expect the unseal to return exactly the
key.  Since TPM2 keys have a key property flag that corresponds to
migratable, use that flag instead and make the actual key the only
sealed quantity.  This is secure because the key properties are bound
to a hash in the private part, so if they're altered the key won't
load.

Backwards compatibility is implemented by detecting whether we're
loading a new format key or not and correctly setting migratable from
the last byte of old format keys.

Signed-off-by: James Bottomley 
Reviewed-by: Jarkko Sakkinen 
Tested-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen

KEYS: trusted: Reserve TPM for seal and unseal operations

2021-02-16T08:40:28+00:00

When TPM 2.0 trusted keys code was moved to the trusted keys subsystem,
the operations were unwrapped from tpm_try_get_ops() and tpm_put_ops(),
which are used to take temporarily the ownership of the TPM chip. The
ownership is only taken inside tpm_send(), but this is not sufficient,
as in the key load TPM2_CC_LOAD, TPM2_CC_UNSEAL and TPM2_FLUSH_CONTEXT
need to be done as a one single atom.

Take the TPM chip ownership before sending anything with
tpm_try_get_ops() and tpm_put_ops(), and use tpm_transmit_cmd() to send
TPM commands instead of tpm_send(), reverting back to the old behaviour.

Fixes: 2e19e10131a0 ("KEYS: trusted: Move TPM2 trusted keys code")
Reported-by: "James E.J. Bottomley" 
Cc: stable@vger.kernel.org
Cc: David Howells 
Cc: Mimi Zohar 
Cc: Sumit Garg 
Acked-by Sumit Garg 
Tested-by: Mimi Zohar 
Signed-off-by: Jarkko Sakkinen

tpm: add sysfs exports for all banks of PCR registers

2021-02-16T08:40:27+00:00

Create sysfs per hash groups with 24 PCR files in them one group,
named pcr-, for each agile hash of the TPM.  The files are
plugged in to a PCR read function which is TPM version agnostic, so
this works also for TPM 1.2 but the hash is only sha1 in that case.

Note: the macros used to create the hashes emit spurious checkpatch
warnings.  Do not try to "fix" them as checkpatch recommends, otherwise
they'll break.

Signed-off-by: James Bottomley 
Reviewed-by: Jerry Snitselaar 
Tested-by: Thiago Jung Bauermann 
Tested-by: Jarkko Sakkinen 
Reviewed-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen

tpm: Unify the mismatching TPM space buffer sizes

2020-07-24T06:26:23+00:00

The size of the buffers for storing context's and sessions can vary from
arch to arch as PAGE_SIZE can be anything between 4 kB and 256 kB (the
maximum for PPC64). Define a fixed buffer size set to 16 kB. This should be
enough for most use with three handles (that is how many we allow at the
moment). Parametrize the buffer size while doing this, so that it is easier
to revisit this later on if required.

Cc: stable@vger.kernel.org
Reported-by: Stefan Berger 
Fixes: 745b361e989a ("tpm: infrastructure for TPM spaces")
Reviewed-by: Jerry Snitselaar 
Tested-by: Stefan Berger 
Signed-off-by: Jarkko Sakkinen

security: keys: trusted: fix lost handle flush

2019-12-17T09:46:43+00:00

The original code, before it was moved into security/keys/trusted-keys
had a flush after the blob unseal.  Without that flush, the volatile
handles increase in the TPM until it becomes unusable and the system
either has to be rebooted or the TPM volatile area manually flushed.
Fix by adding back the lost flush, which we now have to export because
of the relocation of the trusted key code may cause the consumer to be
modular.

Signed-off-by: James Bottomley 
Fixes: 2e19e10131a0 ("KEYS: trusted: Move TPM2 trusted keys code")
Reviewed-by: Jerry Snitselaar 
Reviewed-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen

KEYS: trusted: Move TPM2 trusted keys code

2019-11-12T19:45:37+00:00

Move TPM2 trusted keys code to trusted keys subsystem. The reason
being it's better to consolidate all the trusted keys code to a single
location so that it can be maintained sanely.

Also, utilize existing tpm_send() exported API which wraps the internal
tpm_transmit_cmd() API.

Suggested-by: Jarkko Sakkinen 
Signed-off-by: Sumit Garg 
Reviewed-by: Jarkko Sakkinen 
Tested-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen

tpm: Move tpm_buf code to include/linux/

2019-11-12T19:45:37+00:00

Move tpm_buf code to common include/linux/tpm.h header so that it can
be reused via other subsystems like trusted keys etc.

Also rename trusted keys and asymmetric keys usage of TPM 1.x buffer
implementation to tpm1_buf to avoid any compilation errors.

Suggested-by: Jarkko Sakkinen 
Signed-off-by: Sumit Garg 
Reviewed-by: Jerry Snitselaar 
Reviewed-by: Jarkko Sakkinen 
Tested-by: Jarkko Sakkinen 
Signed-off-by: Jarkko Sakkinen