In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: mgmt: hold reference for hci_conn in mgmt_pending_cmds
Dereferencing RCU-protected pointers outside critical sections is invalid and may lead to UAF. Use of hci_conn in hci_sync callbacks also needs to hold refcount to avoid UAF.
Take appropriate locks for hci_conn lookups, and take refcount for hci_conn pointers stored in mgmt_pending_cmd so that the pointer stays valid.
When accessing conn->state, ensure hdev->lock is held to avoid data race.
References
- https://git.kernel.org/stable/c/b56f2ecafc08f372bf0529f9c4f3f429cb1702dc
- https://git.kernel.org/stable/c/d5b3b484b62bb0f4542e7622789d28871626cdf0
- https://git.kernel.org/stable/c/da55f570191d5d72f10c607a7043b947eb05ea46
- https://git.kernel.org/stable/c/ecdcb55ea1c01dda074406f38058785a69526734
- https://git.kernel.org/stable/c/f915e74b6f18293d1d69a2a3305ef321ff7c0172