I noticed when performing subsequent tpm2 calls over a not zeroed tcti context passed
to Tss2_Tcti_Device_Init I have errors such as:
"WARNING:tcti:src/tss2-tcti/tcti-device.c:321:tcti_device_receive() TPM2 response
size disagrees with number of bytes read from fd 3. Header says 0 but we read 29 bytes.
response: Invalid tag in response header: 0"
I made some experiments: If I put some content different than 0x00 at offset 89 in memory
block passed to RC Tss2_Tcti_Device_Init it fails. That is also true for some other
TSS2_RC Tss2_Tcti_Device_Init (TSS2_TCTI_CONTEXT *tctiContext, size_t *size, const char
I check the description of Tss2_Tcti_Device_Init and didn't find any observation that
tctiContext parameter must point an zeroed memory block, although in the usage examples
the allocated memory is zeroed , calling calloc( 1, <needed size>).
Regarding tctiContext memory block passed to Tss2_Tcti_Device_Init:
1 - Is mandatory zeroing it before calling Tss2_Tcti_Device_Init? If so, is it a case of
2 - No, it isn't, so is there a bug?
TCTI shared library: libtss2-tcti-device.so.0
OS: Enterprise Suse Linux
Thanks in advance,
Marcos A. de Moraes
HPE Security Software Engineer
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