Bluetooth: mgmt: Dequeue pending mesh_send_sync entries on cancel

Overview

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

Bluetooth: mgmt: Dequeue pending mesh_send_sync entries on cancel

In send_cancel(), pending mesh_tx objects are removed from the hdev->mesh_pending list and freed via mesh_send_complete(). However, if a mesh transmission was already queued onto hdev->cmd_sync_work_list via mesh_next(), the queued entry retains a raw pointer to mesh_tx.

When hci_cmd_sync_work later processes the entry, it attempts to execute mesh_send_sync and its destroy callback mesh_send_start_complete using the already freed mesh_tx pointer, leading to a use-after-free.

Fix this by invoking hci_cmd_sync_dequeue() for mesh_send_sync on the target mesh_tx before completing it. If the entry is found and dequeued, its destroy callback will complete and free the object; otherwise, mesh_send_complete() is called directly.

Additionally, ensure the transmission queue advances after cancellation or errors. In mesh_send_start_complete(), call mesh_next() on error unless err is -ECANCELED, because hci_cmd_sync_dequeue() holds hdev->cmd_sync_work_lock and calling mesh_next() synchronously would deadlock. Instead, advance the queue in send_cancel() once the lock is released and if no transmission is in progress.

Affected

• Linux >= b338d91703fae6f6afd67f3f75caa3b8f36ddef3 < f84e52829021d00bca8e067302f597c71af1f71a
• Linux >= b338d91703fae6f6afd67f3f75caa3b8f36ddef3 < 718a8ffa180d469f99ad4f746f00cafd39456415
• Linux >= b338d91703fae6f6afd67f3f75caa3b8f36ddef3 < 084be90948632a5a358821e687b11a14445aae76
• Linux >= b338d91703fae6f6afd67f3f75caa3b8f36ddef3 < 2189a219397d8e73808a67c4aade837b635705da
• Linux >= b338d91703fae6f6afd67f3f75caa3b8f36ddef3 < 03ced4687fb79286be7fdee0fc58d2c74de3e7bb
• Linux >= b338d91703fae6f6afd67f3f75caa3b8f36ddef3 < 71af682ba4692c2ed9ace4c3d4ca462ae368c029
• Linux 6.1

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.