Re: [PATCH net] usbnet: fix error return code in usbnet_probe()

[Johan Hovold]

On Tue, Oct 26, 2021 at 07:25:26PM +0800, Wang Hai wrote:
> Return error code if usb_maxpacket() returns 0 in usbnet_probe().
> 
> Fixes: 397430b50a36 ("usbnet: sanity check for maxpacket")
> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> Signed-off-by: Wang Hai <wanghai38@xxxxxxxxxx>
> ---

Good catch. This is embarrassing. I double checked the error path but
failed to notice the missing return value.

>  drivers/net/usb/usbnet.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/net/usb/usbnet.c b/drivers/net/usb/usbnet.c
> index 80432ee0ce69..fb5bf7d36d50 100644
> --- a/drivers/net/usb/usbnet.c
> +++ b/drivers/net/usb/usbnet.c
> @@ -1790,6 +1790,7 @@ usbnet_probe (struct usb_interface *udev, const struct usb_device_id *prod)
>  	dev->maxpacket = usb_maxpacket (dev->udev, dev->out, 1);
>  	if (dev->maxpacket == 0) {
>  		/* that is a broken device */
> +		status = -EINVAL;

But please use -ENODEV here. -EINVAL is typically reserved for bad user
input.

>  		goto out4;
>  	}

Johan