From 18a6f94766b07b76a325180d101c4e280dcf6a14 Mon Sep 17 00:00:00 2001
From: AlexStocks <alexstocks@foxmail.com>
Date: Tue, 12 Apr 2022 17:59:25 +0800
Subject: [PATCH] fix fatal error: do not handle nil package

---
 protocol/dubbo/dubbo_codec.go | 24 ++++++++++++++----------
 remoting/codec.go             |  2 +-
 remoting/getty/listener.go    |  8 ++++----
 remoting/getty/readwriter.go  | 10 ++++++++--
 4 files changed, 27 insertions(+), 17 deletions(-)

diff --git a/protocol/dubbo/dubbo_codec.go b/protocol/dubbo/dubbo_codec.go
index dee86a9ecd..5f287c3159 100644
--- a/protocol/dubbo/dubbo_codec.go
+++ b/protocol/dubbo/dubbo_codec.go
@@ -160,26 +160,30 @@ func (c *DubboCodec) EncodeResponse(response *remoting.Response) (*bytes.Buffer,
 }
 
 // Decode data, including request and response.
-func (c *DubboCodec) Decode(data []byte) (remoting.DecodeResult, int, error) {
-	var res remoting.DecodeResult
-
+func (c *DubboCodec) Decode(data []byte) (*remoting.DecodeResult, int, error) {
 	dataLen := len(data)
 	if dataLen < impl.HEADER_LENGTH { // check whether header bytes is enough or not
-		return res, 0, nil
+		return nil, 0, nil
 	}
 	if c.isRequest(data) {
 		req, length, err := c.decodeRequest(data)
 		if err != nil {
-			return remoting.DecodeResult{}, length, perrors.WithStack(err)
+			return nil, length, perrors.WithStack(err)
+		}
+		if req == ((*remoting.Request)(nil)) {
+			return nil, length, err
 		}
-		return remoting.DecodeResult{IsRequest: true, Result: req}, length, perrors.WithStack(err)
+		return &remoting.DecodeResult{IsRequest: true, Result: req}, length, perrors.WithStack(err)
 	}
 
-	resp, length, err := c.decodeResponse(data)
+	rsp, length, err := c.decodeResponse(data)
 	if err != nil {
-		return remoting.DecodeResult{}, length, perrors.WithStack(err)
+		return nil, length, perrors.WithStack(err)
 	}
-	return remoting.DecodeResult{IsRequest: false, Result: resp}, length, perrors.WithStack(err)
+	if rsp == ((*remoting.Response)(nil)) {
+		return nil, length, err
+	}
+	return &remoting.DecodeResult{IsRequest: false, Result: rsp}, length, perrors.WithStack(err)
 }
 
 func (c *DubboCodec) isRequest(data []byte) bool {
@@ -247,7 +251,6 @@ func (c *DubboCodec) decodeResponse(data []byte) (*remoting.Response, int, error
 	if err != nil {
 		originErr := perrors.Cause(err)
 		// if the data is very big, so the receive need much times.
-		logger.Errorf("pkg.Unmarshal(len(@data):%d) = error:%+v", buf.Len(), err)
 		if originErr == hessian.ErrHeaderNotEnough { // this is impossible, as dubbo_codec.go:DubboCodec::Decode() line 167
 			return nil, 0, nil
 		}
@@ -255,6 +258,7 @@ func (c *DubboCodec) decodeResponse(data []byte) (*remoting.Response, int, error
 			return nil, hessian.HEADER_LENGTH + pkg.GetBodyLen(), nil
 		}
 
+		logger.Warnf("pkg.Unmarshal(len(@data):%d) = error:%+v", buf.Len(), err)
 		return nil, 0, perrors.WithStack(err)
 	}
 	response := &remoting.Response{
diff --git a/remoting/codec.go b/remoting/codec.go
index d0ede60958..f2d5619699 100644
--- a/remoting/codec.go
+++ b/remoting/codec.go
@@ -26,7 +26,7 @@ import (
 type Codec interface {
 	EncodeRequest(request *Request) (*bytes.Buffer, error)
 	EncodeResponse(response *Response) (*bytes.Buffer, error)
-	Decode(data []byte) (DecodeResult, int, error)
+	Decode(data []byte) (*DecodeResult, int, error)
 }
 
 type DecodeResult struct {
diff --git a/remoting/getty/listener.go b/remoting/getty/listener.go
index 356353950e..c79f242995 100644
--- a/remoting/getty/listener.go
+++ b/remoting/getty/listener.go
@@ -94,8 +94,8 @@ func (h *RpcClientHandler) OnClose(session getty.Session) {
 
 // OnMessage get response from getty server, and update the session to the getty client session list
 func (h *RpcClientHandler) OnMessage(session getty.Session, pkg interface{}) {
-	result, ok := pkg.(remoting.DecodeResult)
-	if !ok {
+	result, ok := pkg.(*remoting.DecodeResult)
+	if !ok || result == ((*remoting.DecodeResult)(nil)) {
 		logger.Errorf("[RpcClientHandler.OnMessage] getty client gets an unexpected rpc result: %#v", result)
 		return
 	}
@@ -232,8 +232,8 @@ func (h *RpcServerHandler) OnMessage(session getty.Session, pkg interface{}) {
 	}
 	h.rwlock.Unlock()
 
-	decodeResult, drOK := pkg.(remoting.DecodeResult)
-	if !drOK {
+	decodeResult, drOK := pkg.(*remoting.DecodeResult)
+	if !drOK || decodeResult == ((*remoting.DecodeResult)(nil)) {
 		logger.Errorf("illegal package{%#v}", pkg)
 		return
 	}
diff --git a/remoting/getty/readwriter.go b/remoting/getty/readwriter.go
index ad95d9e607..18904dc363 100644
--- a/remoting/getty/readwriter.go
+++ b/remoting/getty/readwriter.go
@@ -49,7 +49,10 @@ func (p *RpcClientPackageHandler) Read(ss getty.Session, data []byte) (interface
 	if err != nil {
 		err = perrors.WithStack(err)
 	}
-	if rsp.Result == nil {
+	if rsp == ((*remoting.DecodeResult)(nil)) {
+		return nil, length, err
+	}
+	if rsp.Result == ((*remoting.Response)(nil)) || rsp.Result == ((*remoting.Request)(nil)) {
 		return nil, length, err
 	}
 	return rsp, length, err
@@ -97,7 +100,10 @@ func (p *RpcServerPackageHandler) Read(ss getty.Session, data []byte) (interface
 	if err != nil {
 		err = perrors.WithStack(err)
 	}
-	if req.Result == nil {
+	if req == ((*remoting.DecodeResult)(nil)) {
+		return nil, length, err
+	}
+	if req.Result == ((*remoting.Request)(nil)) || req.Result == ((*remoting.Response)(nil)) {
 		return nil, length, err // as getty rule
 	}
 	return req, length, err