Re: [PATCH v3] sparc: fix error handling in scan_one_device()

[Andreas Larsson]

On 2025-09-20 14:53, Ma Ke wrote:
> Once of_device_register() failed, we should call put_device() to
> decrement reference count for cleanup. Or it could cause memory leak.
> So fix this by calling put_device(), then the name can be freed in
> kobject_cleanup().
> 
> Calling path: of_device_register() -> of_device_add() -> device_add().
> As comment of device_add() says, 'if device_add() succeeds, you should
> call device_del() when you want to get rid of it. If device_add() has
> not succeeded, use only put_device() to drop the reference count'.
> 
> Found by code review.
> 
> Cc: stable@xxxxxxxxxxxxxxx
> Fixes: cf44bbc26cf1 ("[SPARC]: Beginnings of generic of_device framework.")
> Signed-off-by: Ma Ke <make24@xxxxxxxxxxx>
> ---
> Changes in v3:
> - also fixed the same problem in arch/sparc/kernel/of_device_32.c as suggestions.
> Changes in v2:
> - retained kfree() manually due to the lack of a release callback function.
> ---
>  arch/sparc/kernel/of_device_32.c | 1 +
>  arch/sparc/kernel/of_device_64.c | 1 +
>  2 files changed, 2 insertions(+)
> 
> diff --git a/arch/sparc/kernel/of_device_32.c b/arch/sparc/kernel/of_device_32.c
> index 06012e68bdca..284a4cafa432 100644
> --- a/arch/sparc/kernel/of_device_32.c
> +++ b/arch/sparc/kernel/of_device_32.c
> @@ -387,6 +387,7 @@ static struct platform_device * __init scan_one_device(struct device_node *dp,
>  
>  	if (of_device_register(op)) {
>  		printk("%pOF: Could not register of device.\n", dp);
> +		put_device(&op->dev);
>  		kfree(op);
>  		op = NULL;
>  	}
> diff --git a/arch/sparc/kernel/of_device_64.c b/arch/sparc/kernel/of_device_64.c
> index f98c2901f335..f53092b07b9e 100644
> --- a/arch/sparc/kernel/of_device_64.c
> +++ b/arch/sparc/kernel/of_device_64.c
> @@ -677,6 +677,7 @@ static struct platform_device * __init scan_one_device(struct device_node *dp,
>  
>  	if (of_device_register(op)) {
>  		printk("%pOF: Could not register of device.\n", dp);
> +		put_device(&op->dev);
>  		kfree(op);
>  		op = NULL;
>  	}


Reviewed-by: Andreas Larsson <andreas@xxxxxxxxxxx>

Picking this up to my for-next.

Thanks,
Andreas