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Date: Fri, 25 Oct 2024 11:23:56 +0200
From: Florian Westphal <fw@strlen.de>
To: Matthieu Baerts <matttbe@kernel.org>
Cc: Florian Westphal <fw@strlen.de>,
	Pablo Neira Ayuso <pablo@netfilter.org>,
	netfilter-devel@vger.kernel.org,
	Jozsef Kadlecsik <kadlec@netfilter.org>, Phil Sutter <phil@nwl.cc>,
	coreteam@netfilter.org
Subject: Re: Netfilter: suspicious RCU usage in __nft_rule_lookup
Message-ID: <20241025092356.GA11843@breakpoint.cc>
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Matthieu Baerts <matttbe@kernel.org> wrote:
> While at it, I had a question related to the rules' list: in
> __nft_release_basechain() from the same nf_tables_api.c file, list's
> entries are not removed with the _rcu variant → is it OK to do that
> because this function is only called last at the cleanup time, when no
> other readers can iterate over the list? So similar to what is done in
> __nft_release_table()?

Looks like __nft_release_basechain() is broken from start, I don't see
how it can work, it doesn't call synchronize_rcu or anything like that
afaics.

No idea what to do here.