Re: [PATCH v4] net: ravb: Fix possible UAF bug in ravb_remove

From: Zheng Hacker
Date: Thu Aug 31 2023 - 02:46:54 EST


Hi everyone,

After reviewing all comments about the patch. I agree with Jakub. But
adding reference on net_device is a big move. All related drivers must
modify the code.
For now, I couldn't think a better idea about the fix. Thanks for your
effort and sorry for my late reply.

Best regards,
Zheng Wang

Zheng Hacker <hackerzheng666@xxxxxxxxx> 于2023年8月30日周三 12:30写道:
>
> Sorry for my late reply. I'll update another patch later today.
>
> Best regards,
> Zheng
>
> Lee Jones <lee@xxxxxxxxxx> 于2023年8月29日周二 21:46写道:
> >
> > On Tue, 15 Aug 2023, Lee Jones wrote:
> >
> > > On Tue, 25 Jul 2023, Zheng Wang wrote:
> > >
> > > > In ravb_probe, priv->work was bound with ravb_tx_timeout_work.
> > > > If timeout occurs, it will start the work. And if we call
> > > > ravb_remove without finishing the work, there may be a
> > > > use-after-free bug on ndev.
> > > >
> > > > Fix it by finishing the job before cleanup in ravb_remove.
> > > >
> > > > Note that this bug is found by static analysis, it might be
> > > > false positive.
> > > >
> > > > Fixes: c156633f1353 ("Renesas Ethernet AVB driver proper")
> > > > Signed-off-by: Zheng Wang <zyytlz.wz@xxxxxxx>
> > > > Reviewed-by: Sergey Shtylyov <s.shtylyov@xxxxxx>
> > > > ---
> > > > v4:
> > > > - add information about the bug was found suggested by Yunsheng Lin
> > > > v3:
> > > > - fix typo in commit message
> > > > v2:
> > > > - stop dev_watchdog so that handle no more timeout work suggested by Yunsheng Lin,
> > > > add an empty line to make code clear suggested by Sergey Shtylyov
> > > > ---
> > > > drivers/net/ethernet/renesas/ravb_main.c | 3 +++
> > > > 1 file changed, 3 insertions(+)
> > >
> > > Trying my best not to sound like a broken record, but ...
> > >
> > > What's the latest with this fix? Is a v5 en route?
> >
> > Any update please Zheng Wang?
> >
> > --
> > Lee Jones [李琼斯]