From 8a095d0244da237f6eb76c4c24be49a1833b3988 Mon Sep 17 00:00:00 2001
From: Bryce Anderson <banderson@twitter.com>
Date: Thu, 25 Jan 2018 14:26:45 -0700
Subject: [PATCH] Http2MultiplexCodec should propagate unhandled Http2Frames
 down the pipeline

Motivation:

Http2MultiplexCodec swallows Http2PingFrames without releasing the payload, resulting in a memory leak.

Modification:

Send unhandled frames down the pipeline for consumption/disposal by another InboundChannelHandler.

Result:

Fixes #7607.
---
 .../handler/codec/http2/Http2MultiplexCodec.java      |  3 +++
 .../handler/codec/http2/Http2MultiplexCodecTest.java  | 11 +++++++++++
 2 files changed, 14 insertions(+)

diff --git a/codec-http2/src/main/java/io/netty/handler/codec/http2/Http2MultiplexCodec.java b/codec-http2/src/main/java/io/netty/handler/codec/http2/Http2MultiplexCodec.java
index ae98bfea08..aeeec3feb6 100644
--- a/codec-http2/src/main/java/io/netty/handler/codec/http2/Http2MultiplexCodec.java
+++ b/codec-http2/src/main/java/io/netty/handler/codec/http2/Http2MultiplexCodec.java
@@ -227,6 +227,9 @@ public class Http2MultiplexCodec extends Http2FrameCodec {
             if (settings.initialWindowSize() != null) {
                 initialOutboundStreamWindow = settings.initialWindowSize();
             }
+        } else {
+            // Send any other frames down the pipeline
+            ctx.fireChannelRead(frame);
         }
     }
 
diff --git a/codec-http2/src/test/java/io/netty/handler/codec/http2/Http2MultiplexCodecTest.java b/codec-http2/src/test/java/io/netty/handler/codec/http2/Http2MultiplexCodecTest.java
index ecdcdcf7c8..bec5cd964e 100644
--- a/codec-http2/src/test/java/io/netty/handler/codec/http2/Http2MultiplexCodecTest.java
+++ b/codec-http2/src/test/java/io/netty/handler/codec/http2/Http2MultiplexCodecTest.java
@@ -170,6 +170,17 @@ public class Http2MultiplexCodecTest {
         verifyFramesMultiplexedToCorrectChannel(inboundStream, inboundHandler, 2);
     }
 
+    @Test
+    public void unhandledHttp2FramesShouldBePropagated() {
+        ByteBuf content = UnpooledByteBufAllocator.DEFAULT.buffer(8).writeLong(0);
+        Http2PingFrame decodedFrame = new DefaultHttp2PingFrame(content);
+
+        codec.onHttp2Frame(decodedFrame);
+        Http2PingFrame receivedPing = parentChannel.readInbound();
+        assertSame(receivedPing, decodedFrame);
+        assertTrue(receivedPing.release());
+    }
+
     @Test
     public void channelReadShouldRespectAutoRead() {
         LastInboundHandler inboundHandler = streamActiveAndWriteHeaders(inboundStream);