fix TcpDecoder memory leak (#54)

* fix TcpDecoder0 memory leak

* update

Author: JoeCqupt

trpc-transport/trpc-transport-netty/src/main/java/com/tencent/trpc/transport/netty/NettyChannel.java

@@ -35,8 +35,12 @@ public NettyChannel(io.netty.channel.Channel channel, ProtocolConfig config) {
         this.config = config;
         if (channel != null) {
             // can't get the remote address while using udp, so the remoteAddress is null
-            this.remoteAddress = ((InetSocketAddress) channel.remoteAddress());
-            this.localAddress = (InetSocketAddress) channel.localAddress();
+            if (channel.remoteAddress() instanceof InetSocketAddress) {
+                this.remoteAddress = ((InetSocketAddress) channel.remoteAddress());
+            }
+            if (channel.localAddress() instanceof InetSocketAddress) {
+                this.localAddress = (InetSocketAddress) channel.localAddress();
+            }
         }
         // listen for the close event
         if (channel != null && channel.closeFuture() != null) {

trpc-transport/trpc-transport-netty/src/main/java/com/tencent/trpc/transport/netty/NettyCodecAdapter.java

@@ -170,6 +170,9 @@ private void decode(ChannelHandlerContext ctx, ByteBuf input, List<Object> out)
                     }
                 }
             } while (message.isReadable());
+        } catch (Exception e) {
+            message.skipBytes(message.readableBytes());
+            throw new TransportException("tcp|decode failure", e);
         } finally {
             NettyChannelManager.removeChannelIfDisconnected(ctx.channel());
         }

trpc-transport/trpc-transport-netty/src/test/java/com/tencent/trpc/transport/netty/NettyCodecAdapterTest.java

@@ -0,0 +1,82 @@
+package com.tencent.trpc.transport.netty;
+
+import com.tencent.trpc.core.common.config.ProtocolConfig;
+import com.tencent.trpc.core.exception.ErrorCode;
+import com.tencent.trpc.core.exception.TRpcException;
+import com.tencent.trpc.core.exception.TransportException;
+import com.tencent.trpc.core.transport.codec.Codec;
+import io.netty.buffer.AbstractByteBufAllocator;
+import io.netty.buffer.ByteBuf;
+import io.netty.channel.ChannelHandler;
+import io.netty.channel.embedded.EmbeddedChannel;
+import io.netty.handler.codec.DecoderException;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.nio.charset.StandardCharsets;
+
+import static org.mockito.Matchers.any;
+import static org.mockito.Mockito.doThrow;
+import static org.mockito.Mockito.mock;
+
+
+public class NettyCodecAdapterTest {
+
+    @Test
+    public void testTcpDecodeIllegalPacket1() {
+        Codec codec = mock(Codec.class);
+        doThrow(TRpcException.newFrameException(ErrorCode.TRPC_CLIENT_DECODE_ERR, "the request protocol is not trpc"))
+                .when(codec).decode(any(), any());
+
+
+        ProtocolConfig protocolConfig = new ProtocolConfig();
+        // set batchDecoder true
+        protocolConfig.setBatchDecoder(true);
+        NettyCodecAdapter nettyCodecAdapter = NettyCodecAdapter.createTcpCodecAdapter(codec, protocolConfig);
+
+        ChannelHandler decoder = nettyCodecAdapter.getDecoder();
+        EmbeddedChannel embeddedChannel = new EmbeddedChannel();
+        embeddedChannel.pipeline().addLast(decoder);
+
+        ByteBuf byteBuf = AbstractByteBufAllocator.DEFAULT.heapBuffer();
+        byteBuf.writeBytes("testTcpDecodeIllegalPacket1".getBytes(StandardCharsets.UTF_8));
+
+        // write illegal packet
+        EmbeddedChannel tmpEmbeddedChannel = embeddedChannel;
+        DecoderException decoderException = Assert.assertThrows(DecoderException.class, () -> {
+            tmpEmbeddedChannel.writeInbound(byteBuf);
+        });
+
+        Assert.assertTrue(decoderException.getCause() instanceof TransportException);
+        Assert.assertEquals(byteBuf.refCnt(), 0);
+    }
+
+    @Test
+    public void testTcpDecodeIllegalPacket2() {
+        Codec codec = mock(Codec.class);
+        doThrow(TRpcException.newFrameException(ErrorCode.TRPC_CLIENT_DECODE_ERR, "the request protocol is not trpc"))
+                .when(codec).decode(any(), any());
+
+
+        ProtocolConfig protocolConfig = new ProtocolConfig();
+        // set batchDecoder false
+        protocolConfig.setBatchDecoder(false);
+        NettyCodecAdapter nettyCodecAdapter = NettyCodecAdapter.createTcpCodecAdapter(codec, protocolConfig);
+
+        ChannelHandler decoder = nettyCodecAdapter.getDecoder();
+        EmbeddedChannel embeddedChannel = new EmbeddedChannel();
+        embeddedChannel.pipeline().addLast(decoder);
+
+        ByteBuf byteBuf = AbstractByteBufAllocator.DEFAULT.heapBuffer();
+        byteBuf.writeBytes("testTcpDecodeIllegalPacket1".getBytes(StandardCharsets.UTF_8));
+
+        // write illegal packet
+        EmbeddedChannel tmpEmbeddedChannel = embeddedChannel;
+        DecoderException decoderException = Assert.assertThrows(DecoderException.class, () -> {
+            tmpEmbeddedChannel.writeInbound(byteBuf);
+        });
+
+        Assert.assertTrue(decoderException.getCause() instanceof TransportException);
+        Assert.assertEquals(byteBuf.refCnt(), 0);
+    }
+}