Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

ALSA: usx2y: us144mkii: fix work UAF on disconnect

tascam_disconnect() cancels capture_work and midi_in_work before usb_kill_anchored_urbs() kills the capture/MIDI-in URBs. Those URBs self-resubmit, and their completion handlers reschedule the work.

A URB that completes in the small window between cancel_work_sync() and usb_kill_anchored_urbs() therefore re-arms the work after its only cancel. Nothing cancels it again before snd_card_free() frees the card-private tascam structure, so the work handler then runs on freed memory.

Kill the anchored URBs before cancelling the work; once the work is cancelled no remaining URB can complete to re-arm it.