Bluetooth: btusb: validate Realtek vendor event length
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: btusb: validate Realtek vendor event length btusb_recv_event_realtek() reads the event code at data[0] and the Realtek subevent code at data[2] before deciding whether to consume a vendor event as a coredump. For example, the two-byte event ff 00 contains a complete vendor-event header declaring zero parameters. The old classifier still reads a nonexistent third byte and can misclassify the event as a coredump if the adjacent byte is 0x34. Require the HCI event header and first parameter to be present before inspecting the Realtek subevent code. Short events co