Re: [PATCH] drm/panthor: avoid garbage value in panthor_ioctl_dev_query()

[Boris Brezillon <boris.brezillon@collabora.com>]

On Sun, 19 Jan 2025 10:58:29 +0800
Su Hui <suhui@nfschina.com> wrote:

> 'priorities_info' is uninitialized, and the uninitialized value is copied
> to user object when calling PANTHOR_UOBJ_SET(). Using memset to initialize
> 'priorities_info' to avoid this garbage value problem.
> 
> Fixes: f70000ef2352 ("drm/panthor: Add DEV_QUERY_GROUP_PRIORITIES_INFO dev query")
> Signed-off-by: Su Hui <suhui@nfschina.com>

Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>

> ---
>  drivers/gpu/drm/panthor/panthor_drv.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/panthor/panthor_drv.c
> index 0b3fbee3d37a..44f5c72d46c3 100644
> --- a/drivers/gpu/drm/panthor/panthor_drv.c
> +++ b/drivers/gpu/drm/panthor/panthor_drv.c
> @@ -802,6 +802,7 @@ static void panthor_query_group_priorities_info(struct drm_file *file,
>  {
>  	int prio;
>  
> +	memset(arg, 0, sizeof(*arg));
>  	for (prio = PANTHOR_GROUP_PRIORITY_REALTIME; prio >= 0; prio--) {
>  		if (!group_priority_permit(file, prio))
>  			arg->allowed_mask |= BIT(prio);