[PATCH v3 1/1] media: tegra-video: vi: fix invalid u32 return value in format lookup

[PATCH v3 1/1] media: tegra-video: vi: fix invalid u32 return value in format lookup

[Hungyu Lin]

tegra_get_format_fourcc_by_idx() returns a u32 but uses -EINVAL to
signal an out-of-bounds index. This results in a large unsigned
value being returned, which may be interpreted as a valid fourcc.

Returning 0 is not a valid fourcc either. This condition should
never happen, so use WARN_ON_ONCE() to catch unexpected out-of-bounds
access and return a valid fallback format instead.

Suggested-by: Hans Verkuil <hverkuil+cisco@kernel.org>
Fixes: 3d8a97eabef0 ("media: tegra-video: Add Tegra210 Video input driver")
Cc: stable@vger.kernel.org
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Signed-off-by: Hungyu Lin <dennylin0707@gmail.com>
---
 drivers/staging/media/tegra-video/vi.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
index f14cdc7b5211..456134a9e8cf 100644
--- a/drivers/staging/media/tegra-video/vi.c
+++ b/drivers/staging/media/tegra-video/vi.c
@@ -80,8 +80,8 @@ static int tegra_get_format_idx_by_code(struct tegra_vi *vi,
 static u32 tegra_get_format_fourcc_by_idx(struct tegra_vi *vi,
 					  unsigned int index)
 {
-	if (index >= vi->soc->nformats)
-		return -EINVAL;
+	if (WARN_ON_ONCE(index >= vi->soc->nformats))
+		return vi->soc->video_formats[0].fourcc;
 
 	return vi->soc->video_formats[index].fourcc;
 }
-- 
2.34.1

Re: [PATCH v3 1/1] media: tegra-video: vi: fix invalid u32 return value in format lookup

[Denny Lin]

Hi,

The media CI reports a missing Signed-off-by from Ricardo Ribalda,
but this patch was submitted directly by me and has not been handled
by any committer yet.

I believe this is a false positive.

Could you please confirm?

Thanks,
Hungyu

On Wed, May 6, 2026 at 7:22 PM Hungyu Lin <dennylin0707@gmail.com> wrote:
>
> tegra_get_format_fourcc_by_idx() returns a u32 but uses -EINVAL to
> signal an out-of-bounds index. This results in a large unsigned
> value being returned, which may be interpreted as a valid fourcc.
>
> Returning 0 is not a valid fourcc either. This condition should
> never happen, so use WARN_ON_ONCE() to catch unexpected out-of-bounds
> access and return a valid fallback format instead.
>
> Suggested-by: Hans Verkuil <hverkuil+cisco@kernel.org>
> Fixes: 3d8a97eabef0 ("media: tegra-video: Add Tegra210 Video input driver")
> Cc: stable@vger.kernel.org
> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
> Signed-off-by: Hungyu Lin <dennylin0707@gmail.com>
> ---
>  drivers/staging/media/tegra-video/vi.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
> index f14cdc7b5211..456134a9e8cf 100644
> --- a/drivers/staging/media/tegra-video/vi.c
> +++ b/drivers/staging/media/tegra-video/vi.c
> @@ -80,8 +80,8 @@ static int tegra_get_format_idx_by_code(struct tegra_vi *vi,
>  static u32 tegra_get_format_fourcc_by_idx(struct tegra_vi *vi,
>                                           unsigned int index)
>  {
> -       if (index >= vi->soc->nformats)
> -               return -EINVAL;
> +       if (WARN_ON_ONCE(index >= vi->soc->nformats))
> +               return vi->soc->video_formats[0].fourcc;
>
>         return vi->soc->video_formats[index].fourcc;
>  }
> --
> 2.34.1
>

Re: [PATCH v3 1/1] media: tegra-video: vi: fix invalid u32 return value in format lookup

[Ricardo Ribalda Delgado]

Hi Denny

On Thu, May 7, 2026 at 6:06 AM Denny Lin <dennylin0707@gmail.com> wrote:
>
> Hi,
>
> The media CI reports a missing Signed-off-by from Ricardo Ribalda,
> but this patch was submitted directly by me and has not been handled
> by any committer yet.
>
> I believe this is a false positive.

It is indeed a false positive. Sorry about that

Regards!
>
> Could you please confirm?
>
> Thanks,
> Hungyu
>
> On Wed, May 6, 2026 at 7:22 PM Hungyu Lin <dennylin0707@gmail.com> wrote:
> >
> > tegra_get_format_fourcc_by_idx() returns a u32 but uses -EINVAL to
> > signal an out-of-bounds index. This results in a large unsigned
> > value being returned, which may be interpreted as a valid fourcc.
> >
> > Returning 0 is not a valid fourcc either. This condition should
> > never happen, so use WARN_ON_ONCE() to catch unexpected out-of-bounds
> > access and return a valid fallback format instead.
> >
> > Suggested-by: Hans Verkuil <hverkuil+cisco@kernel.org>
> > Fixes: 3d8a97eabef0 ("media: tegra-video: Add Tegra210 Video input driver")
> > Cc: stable@vger.kernel.org
> > Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
> > Signed-off-by: Hungyu Lin <dennylin0707@gmail.com>
> > ---
> >  drivers/staging/media/tegra-video/vi.c | 4 ++--
> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/staging/media/tegra-video/vi.c b/drivers/staging/media/tegra-video/vi.c
> > index f14cdc7b5211..456134a9e8cf 100644
> > --- a/drivers/staging/media/tegra-video/vi.c
> > +++ b/drivers/staging/media/tegra-video/vi.c
> > @@ -80,8 +80,8 @@ static int tegra_get_format_idx_by_code(struct tegra_vi *vi,
> >  static u32 tegra_get_format_fourcc_by_idx(struct tegra_vi *vi,
> >                                           unsigned int index)
> >  {
> > -       if (index >= vi->soc->nformats)
> > -               return -EINVAL;
> > +       if (WARN_ON_ONCE(index >= vi->soc->nformats))
> > +               return vi->soc->video_formats[0].fourcc;
> >
> >         return vi->soc->video_formats[index].fourcc;
> >  }
> > --
> > 2.34.1
> >
>


-- 
Ricardo Ribalda