Fix possible buffer leak when stream can't be mapped (#14746)

Motivation:

We should guard against the sitation where we can't map the stream.
While this should never happen its better to be safe than sorry.

Modifications:

- Ensure the required Http2FrameStream can be found and only after that
try to construct the specific frame.
- Release ByteBuffer when DefaultHttp2DataFrame constructor throws

Result:

Fix possible buffer leaks

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2FrameCodec.java

@@ -604,8 +604,8 @@ public void onUnknownFrame(
                 // Ignore unknown frames on connection stream, for example: HTTP/2 GREASE testing
                 return;
             }
-            onHttp2Frame(ctx, newHttp2UnknownFrame(frameType, streamId, flags, payload.retain())
-                .stream(requireStream(streamId)));
+            Http2FrameStream stream = requireStream(streamId);
+            onHttp2Frame(ctx, newHttp2UnknownFrame(frameType, streamId, flags, payload.retain()).stream(stream));
         }
 
         @Override
@@ -625,7 +625,8 @@ public void onPingAckRead(ChannelHandlerContext ctx, long data) {
 
         @Override
         public void onRstStreamRead(ChannelHandlerContext ctx, int streamId, long errorCode) {
-            onHttp2Frame(ctx, new DefaultHttp2ResetFrame(errorCode).stream(requireStream(streamId)));
+            Http2FrameStream stream = requireStream(streamId);
+            onHttp2Frame(ctx, new DefaultHttp2ResetFrame(errorCode).stream(stream));
         }
 
         @Override
@@ -634,7 +635,8 @@ public void onWindowUpdateRead(ChannelHandlerContext ctx, int streamId, int wind
                 // Ignore connection window updates.
                 return;
             }
-            onHttp2Frame(ctx, new DefaultHttp2WindowUpdateFrame(windowSizeIncrement).stream(requireStream(streamId)));
+            Http2FrameStream stream = requireStream(streamId);
+            onHttp2Frame(ctx, new DefaultHttp2WindowUpdateFrame(windowSizeIncrement).stream(stream));
         }
 
         @Override
@@ -647,22 +649,31 @@ public void onHeadersRead(ChannelHandlerContext ctx, int streamId,
         @Override
         public void onHeadersRead(ChannelHandlerContext ctx, int streamId, Http2Headers headers,
                                   int padding, boolean endOfStream) {
-            onHttp2Frame(ctx, new DefaultHttp2HeadersFrame(headers, endOfStream, padding)
-                    .stream(requireStream(streamId)));
+            Http2FrameStream stream = requireStream(streamId);
+            onHttp2Frame(ctx, new DefaultHttp2HeadersFrame(headers, endOfStream, padding).stream(stream));
         }
 
         @Override
         public int onDataRead(ChannelHandlerContext ctx, int streamId, ByteBuf data, int padding,
                               boolean endOfStream) {
-            onHttp2Frame(ctx, new DefaultHttp2DataFrame(data, endOfStream, padding)
-                    .stream(requireStream(streamId)).retain());
+            Http2FrameStream stream = requireStream(streamId);
+            final Http2DataFrame dataframe;
+            try {
+                dataframe = new DefaultHttp2DataFrame(data.retain(), endOfStream, padding);
+            } catch (IllegalArgumentException e) {
+                // Might be thrown in case of invalid padding / length.
+                data.release();
+                throw e;
+            }
+            dataframe.stream(stream);
+            onHttp2Frame(ctx, dataframe);
             // We return the bytes in consumeBytes() once the stream channel consumed the bytes.
             return 0;
         }
 
         @Override
         public void onGoAwayRead(ChannelHandlerContext ctx, int lastStreamId, long errorCode, ByteBuf debugData) {
-            onHttp2Frame(ctx, new DefaultHttp2GoAwayFrame(lastStreamId, errorCode, debugData).retain());
+            onHttp2Frame(ctx, new DefaultHttp2GoAwayFrame(lastStreamId, errorCode, debugData.retain()));
         }
 
         @Override
@@ -674,8 +685,9 @@ public void onPriorityRead(ChannelHandlerContext ctx, int streamId, int streamDe
                 // The stream was not opened yet, let's just ignore this for now.
                 return;
             }
+            Http2FrameStream frameStream = requireStream(streamId);
             onHttp2Frame(ctx, new DefaultHttp2PriorityFrame(streamDependency, weight, exclusive)
-                    .stream(requireStream(streamId)));
+                    .stream(frameStream));
         }
 
         @Override
@@ -686,10 +698,11 @@ public void onSettingsAckRead(ChannelHandlerContext ctx) {
         @Override
         public void onPushPromiseRead(ChannelHandlerContext ctx, int streamId, int promisedStreamId,
                                       Http2Headers headers, int padding) {
+            Http2FrameStream stream = requireStream(streamId);
             onHttp2Frame(ctx, new DefaultHttp2PushPromiseFrame(headers, padding, promisedStreamId)
                     .pushStream(new DefaultHttp2FrameStream()
                             .setStreamAndProperty(streamKey, connection().stream(promisedStreamId)))
-                    .stream(requireStream(streamId)));
+                    .stream(stream));
         }
 
         private Http2FrameStream requireStream(int streamId) {