Re: drivers: random: Shift out-of-bounds in _mix_pool_bytes

From: Peter Zijlstra
Date: Fri Oct 24 2014 - 09:42:19 EST


On Fri, Oct 24, 2014 at 09:23:35AM -0400, Sasha Levin wrote:
>
> i >> 32 may happen to be "i", but is there anything that prevents the compiler
> from returning, let's say, 42?

Not really, although gcc seems to opt for the 'sane' option and emit the
instruction and let the arch figure out how to deal with it. Hence the
'fun' difference between x86 and ARM.


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