[PATCH RESEND] drm: Fix potential null pointer dereference issues in drm_managed.c

[Dmitry Baryshkov]

On Thu, Jul 03, 2025 at 05:28:19PM +0800, Haoxiang Li wrote:
> Add check for the return value of kstrdup_const() in drm_managed.c
> to prevent potential null pointer dereference.
> 
> Fixes: c6603c740e0e ("drm: add managed resources tied to drm_device")
> Cc: stable at vger.kernel.org
> Signed-off-by: Haoxiang Li <haoxiang_li2024 at 163.com>
> ---
>  drivers/gpu/drm/drm_managed.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/gpu/drm/drm_managed.c b/drivers/gpu/drm/drm_managed.c
> index cc4c463daae7..368763d4c24e 100644
> --- a/drivers/gpu/drm/drm_managed.c
> +++ b/drivers/gpu/drm/drm_managed.c
> @@ -151,6 +151,11 @@ int __drmm_add_action(struct drm_device *dev,
>  	}
>  
>  	dr->node.name = kstrdup_const(name, GFP_KERNEL);
> +	if (!dr->node.name) {
> +		kfree(dr);
> +		return -ENOMEM;
> +	}
> +
>  	if (data) {
>  		void_ptr = (void **)&dr->data;
>  		*void_ptr = data;
> @@ -236,6 +241,10 @@ void *drmm_kmalloc(struct drm_device *dev, size_t size, gfp_t gfp)
>  		return NULL;
>  	}
>  	dr->node.name = kstrdup_const("kmalloc", gfp);
> +	if (dr->node.name) {

This should be `if (!dr->node.name)`.
I think with this fixed the patch is legit and  should be picked up.

> +		kfree(dr);
> +		return NULL;
> +	}
>  
>  	add_dr(dev, dr);
>  
> -- 
> 2.25.1
> 

-- 
With best wishes
Dmitry