Hi, Ville & all
Thanks for quick reply!
According to your reply, the *info has been checked info earlier, and I have read the code of framebuffer_check() and related drm_get_format_info() which it calls, but unfortunatelly, I haven't seen judgement(check) for it. What I only found related with check is the sentence below (in *drm_format_info() in drivers/gpu/drm/drm_fourcc.c)：
```
info = __drm_format_info(format);
WARN_ON(!info);
```
But to the best of my knowledge, "WARN_ON" only gives a dump_stack(), not discontinue the program going on, so it will indeed go to the below line in framebuffer_check() and raise an error:
```
for (i = 0; i < info->num_planes; i++) {
```
So maybe it will make sense of my commited code.
Looking forward to your reply and guidance.
On Fri, Oct 27, 2023 at 05:19:12PM +0800, Peng Hao wrote:
> Since drm_get_format_info() may return NULL,
Not in this case since we already checked it earlier.
> so a judgement of return
> value is needed to add.
>
> Signed-off-by: Peng Hao <penghao@xxxxxxxxxxx>
> ---
> drivers/gpu/drm/drm_framebuffer.c | 4 ++++
> 1 file changed, 4 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c
> index aff3746dedfb..be7dd1998c04 100644
> --- a/drivers/gpu/drm/drm_framebuffer.c
> +++ b/drivers/gpu/drm/drm_framebuffer.c
> @@ -194,6 +194,10 @@ static int framebuffer_check(struct drm_device *dev,
>
> /* now let the driver pick its own format info */
> info = drm_get_format_info(dev, r);
> + if (!info) {
> + drm_dbg_kms(dev, "no matched format info\n");
> + return -EFAULT;
> + }
>
> for (i = 0; i < info->num_planes; i++) {
> unsigned int width = fb_plane_width(r->width, info, i);
> --
> 2.37.1
--
Ville Syrjälä
Intel
