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Date: Sat, 2 May 2026 00:00:25 +0200
From: Florian Westphal <fw@strlen.de>
To: Tristan Madani <tristmd@gmail.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>, Phil Sutter <phil@nwl.cc>,
	netfilter-devel@vger.kernel.org, netdev@vger.kernel.org,
	stable@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/2] netfilter: ip_tables: guard
 ipt_unregister_table_pre_exit against NULL ops
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Tristan Madani <tristmd@gmail.com> wrote:
> That said, the crash is real -- KASAN shows ops=NULL in
> pre_exit during cleanup_net -- so something is reaching that
> path. The V2 guard handles it regardless of the root cause:
> if ops is NULL in pre_exit, we should not pass it to
> nf_unregister_net_hooks.
> 
> I will share any PoC/repro if I get one.

Thanks. I have a patch series that should close all
races, I need to retest it tomorrow and then I'll post it
so sashiko, syzbot etc. can have a go at it.

I found a few other problems in the general area so it should
be a good improvement over the current state of affairs.