Re: [syzbot] WARNING in __nf_unregister_net_hook (4)

From: Pablo Neira Ayuso
Date: Wed May 12 2021 - 20:56:19 EST

On Sat, May 08, 2021 at 04:46:57PM +0200, Florian Westphal wrote:
> Dmitry Vyukov <dvyukov@xxxxxxxxxx> wrote:
> > > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > > Reported-by: syzbot+154bd5be532a63aa778b@xxxxxxxxxxxxxxxxxxxxxxxxx
> >
> > Is this also fixed by "netfilter: arptables: use pernet ops struct
> > during unregister"?
> > The warning is the same, but the stack is different...
> No, this is a different bug.
> In both cases the caller attempts to unregister a hook that the core
> can't find, but in this case the caller is nftables, not arptables.

I see no reproducer for this bug. Maybe I broke the dormant flag handling?

Or maybe syzbot got here after the arptables bug has been hitted?