[PATCH 0/4] Add support for TPM2 log reported via ACPI table

[Petr Vandrovec <petr-pghWNbHTmq7QT0dZR+AlfA@public.gmane.org>]

Hi Peter,

This series of 4 patches adds support for handling TPM2
log when it is reported through ACPI TPM2 table, as
described in latest TPM ACPI draft (Version 1.2, Revision 8,
from February 27th, 2017).

I've tested patch on x86 only - I do not have PPC64 system
with TPM, and handling of endianness between tpm1_eventlog.c
and tpm2_eventlog.c seems inconsistent: tpm1_eventlog.c uses
be32_to_cpu() for all log fields on PPC64, while
tpm2_eventlog.c uses log uses native endianness.  If it
is intentional, and PPC64 has TPM1 logs in big endian
while TPM2 logs in native endianness, then 3rd patch
needs to be amended.

Four patches split task of improving TPM2 support into following
subtasks:


1. Add log start/length fields to TPM2 table

This patch adds 1.2 rev 8 structures to TPM2 table, and
modifies tpm_tis and tpm_crb to use
offsetofend(tpm2, field_accessed) rather than sizeof(tpm2)
to verify that TPM2 table is big enough.


2. Read TCG log from TPM2 table

This patch modifies tpm_acpi code to read log start/length
from TPM2 table similar way it does so from TCPA table.


3. Autodetect TCG event log version

This patch modifies tpm1_eventlog to make decision whether
to use TPM1 or TPM2 format based on log content, rather
than from chip version: on x86 there is dozen of firmwares
that use TPM1 log with TPM2 chip.

Other part of the change is to validate content of specid
event to make sure kernel does not crash when faced with
specid event that claims there is 2^32-1 hashes in the
event list.


4. Improve handling of TPM2 event logs

Current code does not report any error when digest's hash
is not listed in specid event, or if event reports 2^32-1
digests (which is BIOS bug), or if event has more than
3 digests (that is kernel bug).  Instead it will try to
vmalloc() all available memory when event log is read by
userspace application.

This patch updates code so that it can handle arbitrary
number of digests, as long as they are all described
in specid event, and stops parsing as soon as any malformed
event is detected.


Let me know if there are any improvements I can make to
this patch series.

Thanks,
Petr Vandrovec


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