fix:deadlock between CommonDiscoveryService.Stop and CommonDiscoveryS…

…ervice.PushToChan

waku/v2/service/common_discovery_service.go

@@ -49,16 +49,29 @@ func (sp *CommonDiscoveryService) GetListeningChan() <-chan PeerData {
 	return sp.channel
 }
 func (sp *CommonDiscoveryService) PushToChan(data PeerData) bool {
-	sp.RLock()
-	defer sp.RUnlock()
-	if err := sp.ErrOnNotRunning(); err != nil {
-		return false
-	}
+	done := make(chan bool, 1)
+	go func() {
+		sp.RLock()
+		defer sp.RUnlock()
+		if err := sp.ErrOnNotRunning(); err != nil {
+			done <- false
+			return
+		}
+		select {
+		case sp.channel <- data:
+			done <- true
+		case <-sp.Context().Done():
+			done <- false
+		}
+	}()
+
 	select {
-	case sp.channel <- data:
-		return true
 	case <-sp.Context().Done():
+		// should always check if the context is done, otherwise there is a potential for a deadlock.
+		// see https://github.com/status-im/status-go/issues/4527#issuecomment-2047231127
 		return false
+	case result := <-done:
+		return result
 	}
 }