Bluetooth: Fix auth_complete_evt for legacy units

Legacy devices don't re-authenticate the link properly if a link key
already exists.  Thus, don't update sec_level for this case even if
hci_auth_complete_evt indicates success. Otherwise the sec_level will
not reflect a real security on the link.
Signed-off-by: Waldemar Rymarkiewicz <waldemar.rymarkiewicz@tieto.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

include/net/bluetooth/hci_core.h

@@ -322,6 +322,7 @@ void hci_inquiry_cache_update(struct hci_dev *hdev, struct inquiry_data *data);
 /* ----- HCI Connections ----- */
 enum {
 	HCI_CONN_AUTH_PEND,
+	HCI_CONN_REAUTH_PEND,
 	HCI_CONN_ENCRYPT_PEND,
 	HCI_CONN_RSWITCH_PEND,
 	HCI_CONN_MODE_CHANGE_PEND,

net/bluetooth/hci_conn.c

@@ -548,6 +548,8 @@ static int hci_conn_auth(struct hci_conn *conn, __u8 sec_level, __u8 auth_type)
 		cp.handle = cpu_to_le16(conn->handle);
 		hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
 							sizeof(cp), &cp);
+		if (conn->key_type != 0xff)
+			set_bit(HCI_CONN_REAUTH_PEND, &conn->pend);
 	}
 
 	return 0;

net/bluetooth/hci_event.c

@@ -1489,13 +1489,21 @@ static inline void hci_auth_complete_evt(struct hci_dev *hdev, struct sk_buff *s
 	conn = hci_conn_hash_lookup_handle(hdev, __le16_to_cpu(ev->handle));
 	if (conn) {
 		if (!ev->status) {
-			conn->link_mode |= HCI_LM_AUTH;
-			conn->sec_level = conn->pending_sec_level;
+			if (!(conn->ssp_mode > 0 && hdev->ssp_mode > 0) &&
+						test_bit(HCI_CONN_REAUTH_PEND,
+						&conn->pend)) {
+				BT_INFO("re-auth of legacy device is not"
+								"possible.");
+			} else {
+				conn->link_mode |= HCI_LM_AUTH;
+				conn->sec_level = conn->pending_sec_level;
+			}
 		} else {
 			mgmt_auth_failed(hdev->id, &conn->dst, ev->status);
 		}
 
 		clear_bit(HCI_CONN_AUTH_PEND, &conn->pend);
+		clear_bit(HCI_CONN_REAUTH_PEND, &conn->pend);
 
 		if (conn->state == BT_CONFIG) {
 			if (!ev->status && hdev->ssp_mode > 0 &&