Linux Kernel USB MIDI Deadlock Vulnerability

A deadlock vulnerability has been identified in the USB MIDI gadget functionality of the Linux kernel. This issue arises from a re-entrant call to the 'f_midi_transmit' function, where a lock is attempted to be acquired twice, leading to a deadlock situation. The vulnerability has been resolved by modifying the 'f_midi_complete' function to use 'queue_work()' for scheduling the 'f_midi_transmit()' call via a high-priority work queue, thereby preventing the deadlock.

Impact

Exploitation of this vulnerability leads to a deadlock condition, causing the system to become unresponsive or to hang indefinitely while waiting for a resource to become available.