Re: [RESEND PATCH v2] media: mtk-jpeg: Fix use after free bug due to uncanceled work

[Zheng Hacker]

Thanks dor your kind reply. I'll try to connect them later.

Best regards,
Zheng

Alexandre Mergnat <amergnat@xxxxxxxxxxxx> 于2023年7月19日周三 18:17写道：
>
>
>
> On 18/07/2023 05:07, Zheng Hacker wrote:
> > Friendly ping
> >
> > Zheng Hacker <hackerzheng666@xxxxxxxxx> 于2023年7月16日周日 00:08写道：
> >>
> >> Hi,
> >>
> >> This issue has not been resolved for a long time. Is there anyone who can help?
> >>
> >> Best regards,
> >> Zheng
> >>
> >> Alexandre Mergnat <amergnat@xxxxxxxxxxxx> 于2023年7月7日周五 22:11写道：
> >>>
> >>>
> >>>
> >>> On 07/07/2023 11:24, Zheng Wang wrote:
> >>>> In mtk_jpeg_probe, &jpeg->job_timeout_work is bound with
> >>>> mtk_jpeg_job_timeout_work. Then mtk_jpeg_dec_device_run
> >>>> and mtk_jpeg_enc_device_run may be called to start the
> >>>> work.
> >>>> If we remove the module which will call mtk_jpeg_remove
> >>>> to make cleanup, there may be a unfinished work. The
> >>>> possible sequence is as follows, which will cause a
> >>>> typical UAF bug.
> >>>>
> >>>> Fix it by canceling the work before cleanup in the mtk_jpeg_remove
> >>>>
> >>>> CPU0                  CPU1
> >>>>
> >>>>                       |mtk_jpeg_job_timeout_work
> >>>> mtk_jpeg_remove     |
> >>>>     v4l2_m2m_release  |
> >>>>       kfree(m2m_dev); |
> >>>>                       |
> >>>>                       | v4l2_m2m_get_curr_priv
> >>>>                       |   m2m_dev->curr_ctx //use
> >>>
> >>> Reviewed-by: Alexandre Mergnat <amergnat@xxxxxxxxxxxx>
> >>>
> >>> --
> >>> Regards,
> >>> Alexandre
>
> Hi Zheng,
>
> If you asking me to merge patch, sorry but I can't, I'm just a reviewer.
> I invite you to ping the maintainers directly:
>
> Bin Liu <bin.liu@xxxxxxxxxxxx> (supporter:MEDIATEK JPEG DRIVER)
> Mauro Carvalho Chehab <mchehab@xxxxxxxxxx> (maintainer:MEDIA INPUT
> INFRASTRUCTURE (V4L/DVB))
> Matthias Brugger <matthias.bgg@xxxxxxxxx> (maintainer:ARM/Mediatek SoC
> support)
>
> Otherwise, I misunderstood what you asking me. If so, can you rephrase
> your question please?
>
> --
> Regards,
> Alexandre