Re: [PATCH,RFC] random: collect cpu randomness

From: Maciej W. Rozycki
Date: Mon Feb 03 2014 - 17:01:29 EST


On Mon, 3 Feb 2014, Theodore Ts'o wrote:

> > How about taking the saved registers from the interrupted CPU, xor'ing
> > them all and calling the result random_get_entropy() on systems
> > lacking a good cycles-counter?
>
> So we could take the struct pt_regs which we get from get_irq_regs(),
> XOR them together and use them to feed into input[2] amd input[3] in
> add_interrupt_randomness(). Or some other way of distributing the
> values of all of the irq registers into the __u32 input[4] array.

Can we be sure we don't leak information this way? Just being
paranoid...

Maciej
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