usb devio: handle class_device_create() error

This patch adds missing class_device_create() error check,
and makes notifier return NOTIFY_BAD.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/usb/core/devio.c

@@ -1588,15 +1588,18 @@ const struct file_operations usbfs_device_file_operations = {
 	.release =	usbdev_release,
 };
 
-static void usbdev_add(struct usb_device *dev)
+static int usbdev_add(struct usb_device *dev)
 {
 	int minor = ((dev->bus->busnum-1) * 128) + (dev->devnum-1);
 
 	dev->class_dev = class_device_create(usb_device_class, NULL,
 				MKDEV(USB_DEVICE_MAJOR, minor), &dev->dev,
 				"usbdev%d.%d", dev->bus->busnum, dev->devnum);
+	if (IS_ERR(dev->class_dev))
+		return PTR_ERR(dev->class_dev);
 
 	dev->class_dev->class_data = dev;
+	return 0;
 }
 
 static void usbdev_remove(struct usb_device *dev)
@@ -1609,7 +1612,8 @@ static int usbdev_notify(struct notifier_block *self, unsigned long action,
 {
 	switch (action) {
 	case USB_DEVICE_ADD:
-		usbdev_add(dev);
+		if (usbdev_add(dev))
+			return NOTIFY_BAD;
 		break;
 	case USB_DEVICE_REMOVE:
 		usbdev_remove(dev);