Revert "[nrf noup] bluetooth: conn: Allow for an extra ref in bt_l2ca…

…p_send_pdu"

This reverts commit b0ce7fe.

Signed-off-by: Pavel Vasilyev <pavel.vasilyev@nordicsemi.no>

subsys/bluetooth/host/conn.c

@@ -695,13 +695,7 @@ static int send_buf(struct bt_conn *conn, struct net_buf *buf,
 
 	uint16_t frag_len = MIN(conn_mtu(conn), len);
 
-	if (buf->ref > 1 + (cb ? 1 : 0)) {
-		/* Allow for an additional buffer reference if callback is provided.
-		 * This can be used to extend lifetime of the net buffer until the
-		 * data transmission is confirmed by ACK of the remote.
-		 */
-		__ASSERT_NO_MSG(false);
-	}
+	__ASSERT_NO_MSG(buf->ref == 1);
 
 	if (buf->len > frag_len) {
 		LOG_DBG("keep %p around", buf);

subsys/bluetooth/host/l2cap.c

@@ -717,17 +717,13 @@ static void cancel_data_ready(struct bt_l2cap_le_chan *le_chan)
 int bt_l2cap_send_pdu(struct bt_l2cap_le_chan *le_chan, struct net_buf *pdu,
 		      bt_conn_tx_cb_t cb, void *user_data)
 {
-	/* Allow for an additional buffer reference if callback is provided. This can be used to
-	 * extend lifetime of the net buffer until the data transmission is confirmed by ACK of the
-	 * remote.
-	 */
-	if (pdu->ref > 1 + (cb ? 1 : 0)) {
+	if (pdu->ref != 1) {
 		/* The host may alter the buf contents when fragmenting. Higher
 		 * layers cannot expect the buf contents to stay intact. Extra
 		 * refs suggests a silent data corruption would occur if not for
 		 * this error.
 		 */
-		LOG_ERR("Expecting up to %d refs, got %d", cb ? 2 : 1, pdu->ref);
+		LOG_ERR("Expecting 1 ref, got %d", pdu->ref);
 		return -EINVAL;
 	}