Re: [PATCH v4 0/2] media: pci: Fix invalid access to file *

From: Jacopo Mondi

Date: Tue Oct 14 2025 - 07:52:28 EST


Hi Hans

On Tue, Oct 14, 2025 at 09:05:20AM +0200, Hans Verkuil wrote:
> Hi Jacopo,
>
> On 19/08/2025 09:07, Jacopo Mondi wrote:
> > Since commits
> > 7b9eb53e8591 ("media: cx18: Access v4l2_fh from file")
> > 9ba9d11544f9 ("media: ivtv: Access v4l2_fh from file")
> >
> > All the ioctl handlers access their private data structures
> > from file *
> >
> > The ivtv and cx18 drivers call the ioctl handlers from their
> > DVB layer without a valid file *, causing invalid memory access.
> >
> > The issue has been reported by smatch in
> > "[bug report] media: cx18: Access v4l2_fh from file"
> >
> > Fix this by providing wrappers for the ioctl handlers to be
> > used by the DVB layer that do not require a valid file *.
>
> This series should go to the fixes branch for v6.18, right?
> This looks like a pure regression, so I think that makes sense.
>

I think so, yes

> BTW, why is there a Link: tag in the cx18 patch? It just links to
> the v1 of the patch and that doesn't add meaningful information.
> Linus likes Link:, but only if it really adds useful information.

Good question. I presume it's probably a copy&paste error, as it has no
place in the patch.

Would you like me to resend or will you remove it ?


>
> Regards,
>
> Hans
>
> >
> > Signed-off-by: Jacopo Mondi <jacopo.mondi@xxxxxxxxxxxxxxxx>
> > ---
> > Changes in v4:
> > - Slightly adjust commit messages
> > - Link to v3: https://lore.kernel.org/r/20250818-cx18-v4l2-fh-v3-0-5e2f08f3cadc@xxxxxxxxxxxxxxxx
> >
> > Changes in v3:
> > - Change helpers to accept the type they're going to operate on instead
> > of using the open_id wrapper type as suggested by Laurent
> > - Link to v2: https://lore.kernel.org/r/20250818-cx18-v4l2-fh-v2-0-3f53ce423663@xxxxxxxxxxxxxxxx
> >
> > Changes in v2:
> > - Add Cc: stable@xxxxxxxxxxxxxxx per-patch
> >
> > ---
> > Jacopo Mondi (2):
> > media: cx18: Fix invalid access to file *
> > media: ivtv: Fix invalid access to file *
> >
> > drivers/media/pci/cx18/cx18-driver.c | 9 +++------
> > drivers/media/pci/cx18/cx18-ioctl.c | 30 +++++++++++++++++++-----------
> > drivers/media/pci/cx18/cx18-ioctl.h | 8 +++++---
> > drivers/media/pci/ivtv/ivtv-driver.c | 11 ++++-------
> > drivers/media/pci/ivtv/ivtv-ioctl.c | 22 +++++++++++++++++-----
> > drivers/media/pci/ivtv/ivtv-ioctl.h | 6 ++++--
> > 6 files changed, 52 insertions(+), 34 deletions(-)
> > ---
> > base-commit: a75b8d198c55e9eb5feb6f6e155496305caba2dc
> > change-id: 20250818-cx18-v4l2-fh-7eaa6199fdde
> >
> > Best regards,
>