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Date: Wed, 4 Mar 2026 14:38:57 +0100
From: Florian Westphal <fw@strlen.de>
To: Phil Sutter <phil@nwl.cc>, Helen Koike <koike@igalia.com>,
	Pablo Neira Ayuso <pablo@netfilter.org>,
	netfilter-devel@vger.kernel.org, coreteam@netfilter.org,
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	kernel-dev@igalia.com
Subject: Re: [PATCH] netfilter: nf_tables: fix use-after-free on ops->dev
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Phil Sutter <phil@nwl.cc> wrote:
> > And *THIS* looks buggy.
> > Shouldn't that simply be:
> > 			if (!match || ops)
> > 				continue;

FWIW I can't get the reproducer to trigger a splat with this change.
I've fed this to syzbot to double-check.

> You're right, the 'changename' check in NETDEV_REGISTER is not needed
> because even if not changing names one should skip if already
> registered. Actually, this indicates a bug unless handling
> NETDEV_CHANGENAME. Maybe add a WARN_ON_ONCE()?

Well, it does trigger, afaics.