Date:   Tue, 14 Mar 2023 21:10:28 -0700
From:   Jakub Kicinski <kuba@kernel.org>
To:     Zheng Hacker <hackerzheng666@gmail.com>
Cc:     Zheng Wang <zyytlz.wz@163.com>, davem@davemloft.net,
        edumazet@google.com, pabeni@redhat.com, netdev@vger.kernel.org,
        linux-kernel@vger.kernel.org, 1395428693sheep@gmail.com,
        alex000young@gmail.com
Subject: Re: [PATCH net] net: ethernet: fix use after free bug in
 ns83820_remove_one due to race condition
Message-ID: <20230314211028.6e9cbbcf@kernel.org>
In-Reply-To: <CAJedcCxBn=GE_pQ4xzpnvUmMA6rDuwn_AiE7S7d1EqGF9cHkNw@mail.gmail.com>
References: <20230309094231.3808770-1-zyytlz.wz@163.com>
        <20230313162630.225f6a86@kernel.org>
        <CAJedcCxBn=GE_pQ4xzpnvUmMA6rDuwn_AiE7S7d1EqGF9cHkNw@mail.gmail.com>
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On Tue, 14 Mar 2023 09:59:09 +0800 Zheng Hacker wrote:
> Jakub Kicinski <kuba@kernel.org> =E4=BA=8E2023=E5=B9=B43=E6=9C=8814=E6=97=
=A5=E5=91=A8=E4=BA=8C 07:26=E5=86=99=E9=81=93=EF=BC=9A
> > On Thu,  9 Mar 2023 17:42:31 +0800 Zheng Wang wrote: =20
> > > +     cancel_work_sync(&dev->tq_refill);
> > >       ns83820_disable_interrupts(dev); /* paranoia */
> > >
> > >       unregister_netdev(ndev); =20
> >
> > Canceling the work before unregister can't work.
> > Please take a closer look, the work to refill a ring should be
> > canceled when the ring itself is dismantled. =20
>=20
> Hi Jakub,
>=20
> Thanks for your review! After seeing code again, I found when handling
> IRQ request, it will finally call ns83820_irq->ns83820_do_isr->
> ns83820_rx_kick->schedule_work to start work. So I think we should
> move the code after free_irq. What do you think?

Sorry, we have over 300 patches which need reviews. I don't have=20
the time to help you. Perhaps someone else will.

Please make sure you work on a single networking fix at a time.
All the patches you posted had the same issues.