static ssize_t yurex_read(struct file *file, char __user *buffer, size_t count,
 			  loff_t *ppos)
 {
 	struct usb_yurex *dev;
	int len = 0;
 	char in_buffer[20];
 	unsigned long flags;
 
 	dev = file->private_data;
 
 	mutex_lock(&dev->io_mutex);
 	if (!dev->interface) {		/* already disconnected */
		mutex_unlock(&dev->io_mutex);
		return -ENODEV;
 	}
 
 	spin_lock_irqsave(&dev->lock, flags);
	len = snprintf(in_buffer, 20, "%lld\n", dev->bbu);
 	spin_unlock_irqrestore(&dev->lock, flags);
 	mutex_unlock(&dev->io_mutex);

	return simple_read_from_buffer(buffer, count, ppos, in_buffer, len);
 }

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.