Re: [PATCH] video: fbdev: mmp: Annotate struct mmphw_ctrl with __counted_by

[Gustavo A. R. Silva]

On 9/22/23 11:51, Kees Cook wrote:
> Prepare for the coming implementation by GCC and Clang of the __counted_by
> attribute. Flexible array members annotated with __counted_by can have
> their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
> (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> functions).
>
> As found with Coccinelle[1], add __counted_by for struct mmphw_ctrl.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Helge Deller <deller@xxxxxx>
> Cc: linux-fbdev@xxxxxxxxxxxxxxx
> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

Reviewed-by: Gustavo A. R. Silva <gustavoars@xxxxxxxxxx>

Thanks
--
Gustavo

> ---
>   drivers/video/fbdev/mmp/hw/mmp_ctrl.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/video/fbdev/mmp/hw/mmp_ctrl.h b/drivers/video/fbdev/mmp/hw/mmp_ctrl.h
> index 167585a889d3..719b99a9bc77 100644
> --- a/drivers/video/fbdev/mmp/hw/mmp_ctrl.h
> +++ b/drivers/video/fbdev/mmp/hw/mmp_ctrl.h
> @@ -1406,7 +1406,7 @@ struct mmphw_ctrl {
>   
>   	/*pathes*/
>   	int path_num;
> -	struct mmphw_path_plat path_plats[];
> +	struct mmphw_path_plat path_plats[] __counted_by(path_num);
>   };
>   
>   static inline int overlay_is_vid(struct mmp_overlay *overlay)