Vulnerabilidad · Publicado 02/07/2026 · Actualizado 01/08/2026
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: L2CAP: use chan timer to close channels in cleanup_listen()
l2cap_chan_close() removes the channel from conn->chan_l, which
must be done under conn->lock. cleanup_listen() runs under the
parent sk_lock, so acquiring conn->lock would invert the
established conn->lock -> chan->lock -> sk_lock order.
Instead of calling…
In the Linux kernel, the following vulnerability has been resolved: Bluetooth: L2CAP: use chan timer to close channels in cleanup_listen() l2cap_chan_close() removes the channel from conn->chan_l, which must be done under conn->lock. cleanup_listen() runs under the parent sk_lock, so acquiring conn->lock would invert the established conn->lock -> chan->lock -> sk_lock order. Instead of calling l2cap_chan_close() directly, schedule l2cap_chan_timeout with delay 0 to close the channel asynchronously. The timeout handler already acquires conn->lock and chan->lock in the correct order. The timer is only armed when chan->conn is still set: if it is already NULL, l2cap_conn_del() has already processed this channel (l2cap_chan_del + l2cap_sock_teardown_cb + l2cap_sock_close_cb), so there is nothing left to do. If l2cap_conn_del() races in after the timer is armed, __clear_chan_timer() inside l2cap_chan_del() cancels it; if the timer has already fired, the handler returns harmlessly because chan->conn was cleared.
Score: 8.8/10 — Severidad: HIGH — Estado NIST: Analyzed
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Linux kernel — Linux
CWE-667
Publicado en NIST NVD.