]> git.baikalelectronics.ru Git - kernel.git/commit
tpm: Issue a TPM2_Shutdown for TPM2 devices.
authorJosh Zimmerman <joshz@google.com>
Sun, 25 Jun 2017 21:53:24 +0000 (14:53 -0700)
committerJames Morris <james.l.morris@oracle.com>
Thu, 6 Jul 2017 23:49:24 +0000 (09:49 +1000)
commit23b2857cb465c83960a65dc865dc3086b72ad96b
treef43ed322b34945692400b32841b4fae80b97d3a8
parent21cd0525614d3b413a95d6ed0814f2662c4396ab
tpm: Issue a TPM2_Shutdown for TPM2 devices.

If a TPM2 loses power without a TPM2_Shutdown command being issued (a
"disorderly reboot"), it may lose some state that has yet to be
persisted to NVRam, and will increment the DA counter. After the DA
counter gets sufficiently large, the TPM will lock the user out.

NOTE: This only changes behavior on TPM2 devices. Since TPM1 uses sysfs,
and sysfs relies on implicit locking on chip->ops, it is not safe to
allow this code to run in TPM1, or to add sysfs support to TPM2, until
that locking is made explicit.

Signed-off-by: Josh Zimmerman <joshz@google.com>
Cc: stable@vger.kernel.org
Fixes: 9ac40e865034 ("tpm: fix suspend/resume paths for TPM 2.0")
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
drivers/char/tpm/tpm-chip.c
drivers/char/tpm/tpm-sysfs.c