Description
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.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
7ab56c3a6eccb215034b0cb096e0313441cbf2a4 to < fc0c3b9cf27cfa2a06f66dae1d08c668fe0a2faaaffected7ab56c3a6eccb215034b0cb096e0313441cbf2a4 to < 9901f847a762a5d953871dd95767ce2aed3d684daffected7ab56c3a6eccb215034b0cb096e0313441cbf2a4 to < 4a0bb0fd63fe2b0c62e1072cd1811d6f61e0081caffected7ab56c3a6eccb215034b0cb096e0313441cbf2a4 to < 8daaf7f73fe998631a160d1a5a7e1b0b0480eef8affected7ab56c3a6eccb215034b0cb096e0313441cbf2a4 to < 8de7b386ffad480ca59222b688c94a2da8f0d805affected7ab56c3a6eccb215034b0cb096e0313441cbf2a4 to < d5616beb3355b5fca2280d796c1cf7ada4ee6551affected7ab56c3a6eccb215034b0cb096e0313441cbf2a4 to < e96fbac8d3a73b0bc165383c092a30628561d320affected7ab56c3a6eccb215034b0cb096e0313441cbf2a4 to < 2641a9e0a1dd4af2e21995470a21d55dd35e5203affectedee805f9499ebd0edf0877990968543c752043b59affected3.15.5 to < 3.16affected
Linux Linux
Default version status: affected
3.16affected0 to < 3.16unaffected5.10.261 to ≤ 5.10.*unaffected5.15.212 to ≤ 5.15.*unaffected6.1.178 to ≤ 6.1.*unaffected6.6.145 to ≤ 6.6.*unaffected6.12.97 to ≤ 6.12.*unaffected6.18.39 to ≤ 6.18.*unaffected7.1.4 to ≤ 7.1.*unaffected7.2 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/fc0c3b9cf27cfa2a06f66dae1d08c668fe0a2faa ↗
- https://git.kernel.org/stable/c/9901f847a762a5d953871dd95767ce2aed3d684d ↗
- https://git.kernel.org/stable/c/4a0bb0fd63fe2b0c62e1072cd1811d6f61e0081c ↗
- https://git.kernel.org/stable/c/8daaf7f73fe998631a160d1a5a7e1b0b0480eef8 ↗
- https://git.kernel.org/stable/c/8de7b386ffad480ca59222b688c94a2da8f0d805 ↗
- https://git.kernel.org/stable/c/d5616beb3355b5fca2280d796c1cf7ada4ee6551 ↗
- https://git.kernel.org/stable/c/e96fbac8d3a73b0bc165383c092a30628561d320 ↗
- https://git.kernel.org/stable/c/2641a9e0a1dd4af2e21995470a21d55dd35e5203 ↗