[PATCH v2 2/5] usb: dwc3-generic: Return early when there is no child node

[Marek Vasut]

On 7/16/23 01:10, Jonas Karlman wrote:
> The current error check for device_find_first_child is not working as
> expected, the documentation for device_find_first_child mention:
> 
>    @devp: Returns first child device, or NULL if none
>    Return: 0
> 
> Change to return early when there is no child node to avoid any possible
> null pointer dereference.
> 
> Signed-off-by: Jonas Karlman <jonas at kwiboo.se>
> ---
> v2:
> - Update commit message
> 
>   drivers/usb/dwc3/dwc3-generic.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/dwc3-generic.c b/drivers/usb/dwc3/dwc3-generic.c
> index 35e4b36a695e..4d5d500aefab 100644
> --- a/drivers/usb/dwc3/dwc3-generic.c
> +++ b/drivers/usb/dwc3/dwc3-generic.c
> @@ -558,9 +558,9 @@ int dwc3_glue_probe(struct udevice *dev)
>   			return ret;
>   	}
>   
> -	ret = device_find_first_child(dev, &child);
> -	if (ret)
> -		return ret;
> +	device_find_first_child(dev, &child);
> +	if (!child)
> +		return 0;

What does device_find_first_child() return in your case ? ENODEV or ENOSYS ?