Re: [PATCH v3 1/5] x86,kvm: Add MSR_KVM_GET_RNG_SEED and a matching feature bit

From: Andy Lutomirski
Date: Thu Jul 17 2014 - 13:45:48 EST


On Thu, Jul 17, 2014 at 10:43 AM, Andrew Honig <ahonig@xxxxxxxxxx> wrote:
>> + case MSR_KVM_GET_RNG_SEED:
>> + get_random_bytes(&data, sizeof(data));
>> + break;
>
> Should this be rate limited in the interest of conserving randomness?
> If there ever is an attack on the prng, this would create very
> favorable conditions for an attacker to exploit it.

IMO if the nonblocking pool has a weakness that requires us to
conserve its output, then this is the least of our worries.

--Andy
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