On Wed, May 18, 2022 at 08:15:31PM +0200, Florian Westphal wrote:
> bh might occur while updating per-cpu rnd_state from user context,
> ie. local_out path.
>
> BUG: using smp_processor_id() in preemptible [00000000] code: nginx/2725
> caller is nft_ng_random_eval+0x24/0x54 [nft_numgen]
> Call Trace:
> check_preemption_disabled+0xde/0xe0
> nft_ng_random_eval+0x24/0x54 [nft_numgen]
>
> Use the random driver instead, this also avoids need for local prandom
> state.
>
> Based on earlier patch from Pablo Neira.
Applied to nf.git, thanks.
For the record, I have also added to the commit description:
Moreover, prandom now uses the random driver since d4150779e60f
("random32: use real rng for non-deterministic randomness").
