CVE-2026-97975: Bluetooth: hci_sysfs: Fix NULL pointer dereference in device_del()
Bluetooth: hcisysfs: Fix NULL pointer dereference in devicedel()
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.6.159.1-1 - Compensating control
In hci_conn_init_sysfs(), take an explicit reference to the parent device with get_device(&hdev->dev), and release it with put_device(parent) in bt_link_release() when the connection device is freed.
- Compensating control
In hci_conn_del_sysfs(), restore the __match_tty filter by using device_find_child(..., __match_tty) instead of device_find_any_child(), so device_move() is invoked only for persistent RFCOMM TTY devices.
Event History
Frequently Asked Questions
Which systems are exposed to this race?
Linux kernel systems using Bluetooth HCI sysfs where child devices are present can be exposed. The described example is a BNEP network device being unregistered while Bluetooth connection sysfs cleanup reparents child devices.
What must happen for the failure to occur?
Child-device unregistration must run concurrently with hci_conn_del_sysfs() reparenting that child device. The conflicting operations can leave device_del() using a stale parent reference and trigger a NULL pointer dereference in klist_put().