Date:   Fri, 03 Feb 2023 20:19:21 -0800
From:   John Fastabend <john.fastabend@gmail.com>
To:     Hsin-Wei Hung <hsinweih@uci.edu>,
        John Fastabend <john.fastabend@gmail.com>,
        Jakub Sitnicki <jakub@cloudflare.com>
Cc:     "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>, netdev@vger.kernel.org,
        bpf@vger.kernel.org, linux-kernel@vger.kernel.org
Message-ID: <63dddcc92fc31_6bb15208e9@john.notmuch>
In-Reply-To: <CABcoxUbyxuEaciKLpSeGN-0xnf8H1w1CV9BDZi8++cWhKtQQXw@mail.gmail.com>
References: <CABcoxUbyxuEaciKLpSeGN-0xnf8H1w1CV9BDZi8++cWhKtQQXw@mail.gmail.com>
Subject: RE: A potential deadlock in sockhash map
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Hsin-Wei Hung wrote:
> Hi,
> 
> Our bpf runtime fuzzer (a customized syzkaller) triggered a lockdep warning
> in the bpf subsystem indicating a potential deadlock. We are able to
> trigger this bug on v5.15.25 and v5.19. The following code is a BPF PoC,
> and the lockdep warning is attached at the end.

Thanks, but can you test the latest kernel?

Or at least latest 5.15 stable, 5.15.25 is a bit old and is missing lots of
fixes. And 5.19 is not even a LTS so wouldn't have many fixes.

Ideally if possible testing bpf tree would be the most helpful.

 https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/

I believe we fixed a similar bug already so hoping this is just hitting an
already fixed bug. But, would be best to confirm thanks.

Thanks,
John