Bluetooth: hci_sync: Fix queuing commands when HCI_UNREGISTER is set

jira VULN-50082
jira VULN-50081
cve CVE-2022-49136
commit-author Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
commit 0b94f26

hci_cmd_sync_queue shall return an error if HCI_UNREGISTER flag has
been set as that means hci_unregister_dev has been called so it will
likely cause a uaf after the timeout as the hdev will be freed.

	Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
	Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
(cherry picked from commit 0b94f26)
	Signed-off-by: Jonathan Maple <jmaple@ciq.com>

Author: PlaidCat

net/bluetooth/hci_sync.c

@@ -379,6 +379,9 @@ int hci_cmd_sync_queue(struct hci_dev *hdev, hci_cmd_sync_work_func_t func,
 {
 	struct hci_cmd_sync_work_entry *entry;
 
+	if (hci_dev_test_flag(hdev, HCI_UNREGISTER))
+		return -ENODEV;
+
 	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
 	if (!entry)
 		return -ENOMEM;