CVE-2026-64206

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

Bluetooth: L2CAP: cancel pending_rx_work before taking conn->lock

l2cap_conn_del() takes conn->lock and then calls cancel_work_sync() for

pending_rx_work. process_pending_rx() takes the same mutex, so teardown

can deadlock against the worker it is flushing.

This issue was found by our static analysis tool and then manually

reviewed against the current tree.

The grounded PoC kept the l2cap_conn_ready() -> queue_work(...,

&conn->pending_rx_work) submit path, the l2cap_conn_del() ->

cancel_work_sync(&conn->pending_rx_work) teardown path, and the

process_pending_rx() -> mutex_lock(&conn->lock) worker edge. Lockdep

WARNING: possible circular locking dependency detected

process_pending_rx+0x21/0x2a [vuln_msv]

l2cap_conn_del.constprop.0+0x3f/0x4e [vuln_msv]

*** DEADLOCK ***

Cancel pending_rx_work before taking conn->lock, matching the existing

lock-before-drain ordering used for the two delayed works in the same

teardown path. The pending_rx queue is still purged after the work has

been cancelled and conn->lock has been acquired.