[openssl-dev] Question about valgrind error in DH in 1.0.2

[Henrik Grindal Bakken]

Andy Polyakov <appro at openssl.org> writes:

>> Changing the movzwl to movzbl in bn_get_bits5 eliminates the valgrind
>> error.  But this isn't a valid fix since bn_get_bits5 no longer returns
>> the correct data.  My assembly skills are near nil.  Maybe someone else
>> can propose a valid fix. 
>> 
>> Having said this, this does show the problem appears to be due to the
>> movzwl reading past the end of the buffer by a byte.
>
> Correct.
>
>> Given the data allocated on the heap is likely surrounded by guard
>> bytes, this is likely a benign read outside the buffer.
>
> Correct.
>
>> But it should still be fixed.
>
> Test attached.

This patches fixed the valgrind errors for me.

-- 
Henrik Grindal Bakken <hgb at ifi.uio.no>
PGP ID: 8D436E52
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