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Date: Fri, 3 Apr 2026 15:59:22 +0200
From: Florian Westphal <fw@strlen.de>
To: Scott Mitchell <scott.k.mitch1@gmail.com>
Cc: netfilter-devel@vger.kernel.org
Subject: Re: nfnetlink_queue crashes kernel
Message-ID: <ac_HuuPNrGxpW7CL@strlen.de>
References: <ac-w6e33txkgTRJj@strlen.de>
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Florian Westphal <fw@strlen.de> wrote:
> 2) a4400a5b343d ("netfilter: nfnetlink_queue: nfqnl_instance GFP_ATOMIC -> GFP_KERNEL_ACCOUNT allocation") should have updated the spinlock to use the _bh variant, if the queue exists we risk deadlock via softirq recursion.

Nope, this one is fine, the instance lock is only taken from process
context, but 1) still stands.