CVE-2026-64405

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

Bluetooth: hci_conn: Fix null ptr deref in hci_abort_conn()

hci_abort_conn() read hci_skb_event(hdev->sent_cmd) when a connection

was pending, but hdev->sent_cmd can be NULL while req_status is still

HCI_REQ_PEND, leading to a NULL pointer dereference and a general

protection fault from the hci_rx_work() receive path.

Instead of inspecting hdev->sent_cmd, track the in-flight create

connection command with a new per-connection HCI_CONN_CREATE flag and

route all cancellation through hci_cancel_connect_sync(), which

dispatches to a dedicated per-type cancel function. The create command

is in exactly one of two states: still queued, or in flight. The cancel

function holds cmd_sync_work_lock across the whole decision: the worker

takes this lock to dequeue every entry, so while it is held a queued

command cannot start running and an in-flight command cannot complete

and let the next command become pending. This keeps the flag test and

hci_cmd_sync_cancel() atomic with respect to the worker, so a queued

command is simply dequeued, and an in-flight command owned by this

connection is cancelled without the risk of cancelling an unrelated

command that became pending in the meantime. CIS uses the same flag

mechanism via HCI_CONN_CREATE_CIS but cannot be dequeued per-connection.

hci_acl_create_conn_sync() and hci_le_create_conn_sync() clear

HCI_CONN_CREATE after the create command completes, but the command

status handler can free conn via hci_conn_del() (for example when the

controller rejects the connection) while the worker is still blocked on

the connection complete event. Hold a reference on conn across the

create command so the flag can be cleared without a use-after-free.