Linux Kernel: L2CAP Channel Lock Ordering Race in Bluetooth
CVE-2026-53358 Published on July 2, 2026
Bluetooth: L2CAP: use chan timer to close channels in cleanup_listen()
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.
Products Associated with CVE-2026-53358
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Affected Versions
Linux:- Version 3df91ea20e744344100b10ae69a17211fcf5b207 and below 3634cbdc2eb414b69ffa752ddbe5e0458518e321 is affected.
- Version 3df91ea20e744344100b10ae69a17211fcf5b207 and below e1c100e2d61bd8c718b7d91fe3e050780a9bf72d is affected.
- Version 3df91ea20e744344100b10ae69a17211fcf5b207 and below deb8493a8fa599f6c95e2465b12bfdfb7f94a1d9 is affected.
- Version 3df91ea20e744344100b10ae69a17211fcf5b207 and below 89dec92041717b027216e110599e4f6d6c921b79 is affected.
- Version 3df91ea20e744344100b10ae69a17211fcf5b207 and below 50dfec218808b148ab4247b1858031b7a32015c5 is affected.
- Version 3df91ea20e744344100b10ae69a17211fcf5b207 and below 859d3ace791ed878ae9ba5522c7844d960da8f88 is affected.
- Version 3df91ea20e744344100b10ae69a17211fcf5b207 and below 7555fd885a0603f50e49a655850a1f2bd8a25398 is affected.
- Version 3df91ea20e744344100b10ae69a17211fcf5b207 and below 8c8e620467a7b51562dbcefbd1f09f288d7d710d is affected.
- Version 3.4 is affected.
- Before 3.4 is unaffected.
- Version 5.10.259, <= 5.10.* is unaffected.
- Version 5.15.210, <= 5.15.* is unaffected.
- Version 6.1.176, <= 6.1.* is unaffected.
- Version 6.6.143, <= 6.6.* is unaffected.
- Version 6.12.93, <= 6.12.* is unaffected.
- Version 6.18.35, <= 6.18.* is unaffected.
- Version 7.0.12, <= 7.0.* is unaffected.
- Version 7.1, <= * is unaffected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.