If P2P connection exists compare overlay address (#1059)

pkg/kademlia/kademlia.go

@@ -336,6 +336,10 @@ func (k *Kad) connect(ctx context.Context, peer swarm.Address, ma ma.Multiaddr,
 	i, err := k.p2p.Connect(ctx, ma)
 	if err != nil {
 		if errors.Is(err, p2p.ErrAlreadyConnected) {
+			if !i.Overlay.Equal(peer) {
+				return errOverlayMismatch
+			}
+
 			return nil
 		}
 

pkg/p2p/libp2p/libp2p.go

@@ -453,8 +453,12 @@ func (s *Service) Connect(ctx context.Context, addr ma.Multiaddr) (address *bzz.
 
 	remoteAddr := addr.Decapsulate(hostAddr)
 
-	if _, found := s.peers.isConnected(info.ID, remoteAddr); found {
-		return nil, p2p.ErrAlreadyConnected
+	if overlay, found := s.peers.isConnected(info.ID, remoteAddr); found {
+		address = &bzz.Address{
+			Overlay:  overlay,
+			Underlay: addr,
+		}
+		return address, p2p.ErrAlreadyConnected
 	}
 
 	if err := s.connectionBreaker.Execute(func() error { return s.host.Connect(ctx, *info) }); err != nil {