Re: [PATCH] x86/entry/64: randomize kernel stack offset upon syscall

[Kees Cook]

On Wed, May 29, 2019 at 10:13:43AM +0000, Reshetova, Elena wrote:
> On related note: the current prng we have in kernel (prandom) is based on a
> *very old* style of prngs, which is basically 4 linear LFSRs xored together. 
> Nowadays, we have much more powerful prngs that show much better
> statistical and even security properties (not cryptographically secure, but still
> not so linear like the one above). 
> What is the reason why we still use a prng that is couple of decades away from the
> state of art in the area? It is actively used, especially by network stack,
> should we update it to smth that is more appropriate (speed would be comparable)?
> 
> I am mostly talking about PCG-based generators:
> http://www.pcg-random.org/
> 
> If people are interested, I could put together a PoC and we have an expert here we can
> consult for providing calculations for min-entropy, HILL entropy and whatever 
> is requested. 

If we get better generators with no speed loss, I can't imagine anyone
objecting. :)

-- 
Kees Cook