Subject: Re: [PATCH v1 net] tcp/dccp: Don't use timer_pending() in reqsk_queue_unlink().

From: Jakub Kicinski <[email-masked]>
Date: Mon, 7 Oct 2024 16:26:10 -0700

On Mon, 7 Oct 2024 07:15:57 -0700 Kuniyuki Iwashima wrote:
> Martin KaFai Lau reported use-after-free [0] in reqsk_timer_handler().
> 
>   """
>   We are seeing a use-after-free from a bpf prog attached to
>   trace_tcp_retransmit_synack. The program passes the req->sk to the
>   bpf_sk_storage_get_tracing kernel helper which does check for null
>   before using it.
>   """

I think this crashes a bunch of selftests, example:

https://netdev-3.bots.linux.dev/vmksft-nf-dbg/results/805581/8-nft-queue-sh/stderr
-- 
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