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

Bluetooth: L2CAP: Fix deadlock in l2cap_conn_del()

l2cap_conn_del() calls cancel_delayed_work_sync() for both info_timer
and id_addr_timer while holding conn->lock. However, the work functions
l2cap_info_timeout() and l2cap_conn_update_id_addr() both acquire
conn->lock, creating a potential AB-BA deadlock if the work is already
executing when l2cap_conn_del() takes the lock.

Move the work cancellations before acquiring conn->lock and use
disable_delayed_work_sync() to additionally prevent the works from
being rearmed after cancellation, consistent with the pattern used in
hci_conn_del().

References

• https://nvd.nist.gov/vuln/detail/CVE-2026-31499
• https://git.kernel.org/stable/c/00fdebbbc557a2fc21321ff2eaa22fd70c078608
• https://git.kernel.org/stable/c/3f26ecbd9cde621dd94be7ef252c7210b965a5c7
• https://git.kernel.org/stable/c/d008460de352e534f6721de829b093368564ec66
• https://git.kernel.org/stable/c/f7f35a4f7fd574f5889bb2e4b397e14cbb83f6da