diff --git a/netbare-core/src/main/java/com/github/megatronking/netbare/NetBareThread.java b/netbare-core/src/main/java/com/github/megatronking/netbare/NetBareThread.java
index 14f1355..00bf3fd 100644
--- a/netbare-core/src/main/java/com/github/megatronking/netbare/NetBareThread.java
+++ b/netbare-core/src/main/java/com/github/megatronking/netbare/NetBareThread.java
@@ -57,6 +57,8 @@
 
 	private PacketsTransfer packetsTransfer;
 
+	private VpnService.Builder builder;
+
 	/* package */ NetBareThread(VpnService vpnService, NetBareConfig config) {
 		super("NetBare");
 		this.mVpnService = vpnService;
@@ -70,6 +72,13 @@ public void interrupt() {
 		NetBareUtils.closeQuietly(vpnDescriptor);
 		NetBareUtils.closeQuietly(input);
 		NetBareUtils.closeQuietly(output);
+		try {
+			builder.establish().close();
+		} catch (IOException e) {
+			NetBareLog.wtf(e);
+		}
+		// Notify NetBareListener that the service is stopped now.
+		NetBare.get().notifyServiceStopped();
 	}
 
 	@Override
@@ -88,10 +97,6 @@ public void run() {
 			// Establish VPN, it runs a while loop unless failed.
 			establishVpn(packetsTransfer);
 		}
-
-		// Notify NetBareListener that the service is stopped now.
-		NetBare.get().notifyServiceStopped();
-
 	}
 
 	private void establishVpn(PacketsTransfer packetsTransfer) {
@@ -125,6 +130,7 @@ private void establishVpn(PacketsTransfer packetsTransfer) {
 		} catch (PackageManager.NameNotFoundException e) {
 			NetBareLog.wtf(e);
 		}
+		this.builder = builder;
 		vpnDescriptor = builder.establish();
 		if (vpnDescriptor == null) {
 			return;
@@ -194,7 +200,7 @@ private void transfer(InputStream input, OutputStream output) throws IOException
 			transfer(buffer, input.read(buffer), output);
 		}
 
-		private void transfer(byte[] packet, int len, OutputStream output) {
+		private synchronized void transfer(byte[] packet, int len, OutputStream output) {
 			if (len < IpHeader.MIN_HEADER_LENGTH) {
 				NetBareLog.w("Ip header length < " + IpHeader.MIN_HEADER_LENGTH);
 				return;
diff --git a/netbare-sample/src/main/kotlin/com/github/megatronking/netbare/sample/MainActivity.kt b/netbare-sample/src/main/kotlin/com/github/megatronking/netbare/sample/MainActivity.kt
index 6bf488a..a17a18c 100644
--- a/netbare-sample/src/main/kotlin/com/github/megatronking/netbare/sample/MainActivity.kt
+++ b/netbare-sample/src/main/kotlin/com/github/megatronking/netbare/sample/MainActivity.kt
@@ -78,7 +78,7 @@ class MainActivity : AppCompatActivity(), NetBareListener {
         }
         // 启动NetBare服务
         mNetBare.start(NetBareConfig.defaultHttpConfig(App.getInstance().getJSK(),
-                interceptorFactories()))
+                interceptorFactories()).newBuilder().addAllowedApplication("none").build())
     }
 
     override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {