GELI BIOS weirdness

[Dimitry Andric]

On 13 Feb 2017, at 21:58, Eric McCorkle <eric at metricspace.net> wrote:
> 
> On 02/13/2017 15:36, Dimitry Andric wrote:
> 
>> This disassembles to:
>> 
>>   0:   66 0f 38 f6 f0          adcx   %eax,%esi
>>   5:   31 c6                   xor    %eax,%esi
>>   7:   8b 4d 14                mov    0x14(%ebp),%ecx
>>   a:   89 cf                   mov    %ecx,%edi
>>   c:   c1 ff 1f                sar    $0x1f,%edi
>>   f:   8b                      .byte 0x8b
> 
> Note that this was truncated, so the sar and .byte are probably a
> truncated instruction.
> 
> Also, when I had printfs in place, I could see the call instructions.
> 
>> My first guess would be that the code simply jumped into garbage.  But
>> can you post the complete .o file somewhere for inspection?
> 
> Attached.
> <gptboot>

Can you please post the file before it's been stripped and objcopied
from ELF to binary format?  That makes it a lot easier to disassemble
and analyze... :)

-Dimitry

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