Re: [tpm2] getting segfaults with tss-2.0.0, abrmd-2.0.0, tools-3.1.0

[Joshua Lock <joshua.g.lock at linux.intel.com>]

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On 18/07/2018 22:17, Scheie, Peter M wrote:
> By the way, does abrmd default to trying to connect to /dev/tpm0?  When 
> working with the emulator on my laptop, I have to start abrmd with 
> '--tcti=libtss2-tcti-mssim.so' but I assume that's just for when there 
> is no TPM device, right?

Correct, if no --tcti value is passed abrmd defaults to using the device 
tcti:
https://github.com/tpm2-software/tpm2-abrmd/blob/2296d48a1004aff5f93d6ec23a50819f2a5c5584/src/tcti-dynamic.c#L138

At line 142 you can see where the default value of the TCTI library file 
property is set to "libtss2-tcti-device.so".

> So, with tpm2-abrmd running, if I call, say, tpm2_pcrlist or 
> tpm2_nvlist, to just query the TPM, it will display the PCRs or the NV 
> indexes but then follow that with a "Segmentation fault", and syslog 
> shows things like this:
> 
> Jun 27 22:32:42 localhost audit[1432]: ANOM_ABEND auid=1000 uid=1000 
> gid=1000 ses=1 pid=1432 comm="gdbus" exe="/usr/bin/tpm2_pcrlist" sig=11
> 
> Jun 27 22:32:42 localhost kernel: gdbus[1432]: segfault at 7f8327acc750 
> ip 00007f8327acc750 sp 00007f8326ab2c38 error 14 in 
> libtss2-mu.so.0.0.0[7f8328284000+3f000]
> 
> Jun 27 22:32:42 localhost kernel[363]: gdbus[1432]: segfault at 
> 7f8327acc750 ip 00007f8327acc750 sp 00007f8326ab2c38 error 14 in 
> libtss2-mu.so.0.0.0[7f8328284000+3f000]
> 
> Trying to write to the TPM, e.g., take ownership, doesn't work at all:
> 
> localhost:~$ tpm2_takeownership -o ownerpass -e endorsepass -l lockpass
> 
> ERROR: Could not change hierarchy for Owner. TPM Error:0x9a2

I just recently learned about tpm2_rc_decode[1], it tells me:

$ ./tools/aux/tpm2_rc_decode 0x9a2
tpm:session(1):authorization failure without DA implications

Is this TPM already configured? Have you replicated on more than one system?

Joshua