USB: check usb_get_extra_descriptor for proper size

When reading an extra descriptor, we need to properly check the minimum
and maximum size allowed, to prevent from invalid data being sent by a
device.

Reported-by: Hui Peng <benquike@gmail.com>
Reported-by: Mathias Payer <mathias.payer@nebelwelt.net>
Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Hui Peng <benquike@gmail.com>
Signed-off-by: Mathias Payer <mathias.payer@nebelwelt.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
{
	struct usb_device *usb_dev;

	usb_dev = to_usb_device(dev);

	if (add_uevent_var(env, "BUSNUM=%03d", usb_dev->bus->busnum))
		return -ENOMEM;

	if (add_uevent_var(env, "DEVNUM=%03d", usb_dev->devnum))
		return -ENOMEM;

	return 0;
}

static int usb_dev_uevent(struct device *dev, struct kobj_uevent_env *env)
{
	struct usb_device *usb_dev;

	usb_dev = to_usb_device(dev);

	if (add_uevent_var(env, "BUSNUM=%03d", usb_dev->bus->busnum))
		return -ENOMEM;

	if (add_uevent_var(env, "DEVNUM=%03d", usb_dev->devnum))
		return -ENOMEM;

	return 0;
}
