CVEvulnerability
CVE-2026-80816
- Status
- Received
- Published
- 2026-09-04
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
ALSA: FCP: Use a private URB for the notification endpoint
fcp_init_notify() used mixer->urb, which snd_usb_mixer_status_create()
allocates for the optional UAC2 status interrupt endpoint and mixer.c
kills, resubmits and frees. On a device with that endpoint,
fcp_init_notify()'s "already set up" early return fires on the status
URB and returns success without doing anything. No FCP notification
URB is submitted, and cmd_done is left zeroed because it is
initialised past that early return and nowhere else. fcp_init() then
issues init1_opcode and wait_for_completion_timeout() would crash
adding to the zeroed wait.head. fcp_cleanup_urb() would also kill and
free mixer.c's status URB.
Use a separate URB in fcp_data, and initialise cmd_done in
fcp_init_private() where fcp_data is allocated. fcp_init_notify() is
reached again after suspend via fcp_reinit(), and the URB kill path in
fcp_notify() completes cmd_done, leaving a stale count that would
satisfy the next command's wait before the device ACKs. Use
reinit_completion() to clear it.
References
- https://git.kernel.org/stable/c/5da21a434171e8ecf1d992c6f1d84c0c706fd395 git.kernel.org
- https://git.kernel.org/stable/c/65aceb45ca91ddb7f7ed178821f481b34da35543 git.kernel.org
- https://git.kernel.org/stable/c/6db3c1d7e2872c9904e05ca8e0515920776a3c9c git.kernel.org
- https://git.kernel.org/stable/c/918b8d231c571c50a00efe92ffc8404a537a0490 git.kernel.org