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Date:   Mon, 22 Aug 2022 22:41:12 +0200
From:   Florian Westphal <fw@strlen.de>
To:     Gabriel Ryan <gabe@cs.columbia.edu>
Cc:     Florian Westphal <fw@strlen.de>,
        Abhishek Shah <abhishek.shah@columbia.edu>,
        coreteam@netfilter.org, davem@davemloft.net, edumazet@google.com,
        kadlec@netfilter.org, kuba@kernel.org, netdev@vger.kernel.org,
        netfilter-devel@vger.kernel.org, pabeni@redhat.com,
        pablo@netfilter.org, linux-kernel@vger.kernel.org
Subject: Re: data-race in nf_tables_newtable / nf_tables_newtable
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Gabriel Ryan <gabe@cs.columbia.edu> wrote:
> Hi Florian,
> 
> I just looked at the lock event trace from our report and it looks
> like two distinct commit mutexes were held when the race was
> triggered. I think the race is probably on the table_handle variable
> on net/netfilter/nf_tables_api.c:1221, and not the table->handle field
> being written to.

See

https://patchwork.ozlabs.org/project/netfilter-devel/patch/20220821085939.571378-1-pablo@netfilter.org/

which makes table_handle per netns.