Re: [PATCH v5 2/3] KEYS: Replace assoc_array with rhashtable

[Jarkko Sakkinen <jarkko@kernel.org>]

On Fri, Nov 06, 2026 at 09:30:45PM +0200, Jarkko Sakkinen wrote:
> > SipHash is also useful for resistance against denial-of-service attacks,
> > where a user puts all their keys in one hash bucket.
> > 
> > As I mentioned, it's already used for secure hash tables elsewhere in
> > the kernel.  That is what it's for; see
> > Documentation/security/siphash.rst.  It's very fast as well, so if you
> > are thinking of cryptography as being something very slow and hard to
> > use, that is not what this is (or ever needed to be).
> > 
> > Let's just use it and not over-complicate things.
> 
> I'm pretty much non-opionated when it comes to this detail. I just
> merely represent all the possible if anything comes up to mind. DoS
> protection that you explained was not something I did even consider so
> that seals it for me.

I'm cutting hairs now but indices + siphash adds to defence in depth as
it only takes DoS protection from SipHash while not protecting a secret.
Not sure if this has that much pratical meaning tho  :-)

Br, Jarkko