Merge pull request kubernetes#131170 from azych/fix_goroutine_leak

Fix goroutine leak

Author: k8s-ci-robot

staging/src/k8s.io/kubelet/go.mod

@@ -10,6 +10,7 @@ require (
 	github.com/emicklei/go-restful/v3 v3.11.0
 	github.com/gogo/protobuf v1.3.2
 	github.com/stretchr/testify v1.10.0
+	go.uber.org/goleak v1.3.0
 	google.golang.org/grpc v1.68.1
 	k8s.io/api v0.0.0
 	k8s.io/apimachinery v0.0.0

staging/src/k8s.io/kubelet/go.sum

@@ -17,6 +17,7 @@ limitations under the License.
 package remotecommand
 
 import (
+	"context"
 	"encoding/json"
 	"errors"
 	"fmt"
@@ -116,7 +117,7 @@ func createStreams(req *http.Request, w http.ResponseWriter, opts *Options, supp
 
 	if ctx.resizeStream != nil {
 		ctx.resizeChan = make(chan remotecommand.TerminalSize)
-		go handleResizeEvents(ctx.resizeStream, ctx.resizeChan)
+		go handleResizeEvents(req.Context(), ctx.resizeStream, ctx.resizeChan)
 	}
 
 	return ctx, true
@@ -409,7 +410,7 @@ WaitForStreams:
 // supportsTerminalResizing returns false because v1ProtocolHandler doesn't support it.
 func (*v1ProtocolHandler) supportsTerminalResizing() bool { return false }
 
-func handleResizeEvents(stream io.Reader, channel chan<- remotecommand.TerminalSize) {
+func handleResizeEvents(reqctx context.Context, stream io.Reader, channel chan<- remotecommand.TerminalSize) {
 	defer runtime.HandleCrash()
 	defer close(channel)
 
@@ -419,7 +420,12 @@ func handleResizeEvents(stream io.Reader, channel chan<- remotecommand.TerminalS
 		if err := decoder.Decode(&size); err != nil {
 			break
 		}
-		channel <- size
+		select {
+		case channel <- size:
+		case <-reqctx.Done():
+			// To prevent go routine leak.
+			return
+		}
 	}
 }
 

staging/src/k8s.io/kubelet/pkg/cri/streaming/remotecommand/httpstream.go

@@ -0,0 +1,82 @@
+/*
+Copyright 2025 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package remotecommand
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"io"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"go.uber.org/goleak"
+
+	"k8s.io/client-go/tools/remotecommand"
+)
+
+func TestHandleResizeEvents(t *testing.T) {
+	var testTerminalSize remotecommand.TerminalSize
+	rawTerminalSize, err := json.Marshal(&testTerminalSize)
+	require.NoError(t, err)
+
+	testCases := []struct {
+		name             string
+		resizeStreamData []byte
+		cancelContext    bool
+		readFromChannel  bool
+	}{
+		{
+			name:             "data attempted to be sent on the channel; channel not read; context canceled",
+			resizeStreamData: rawTerminalSize,
+			cancelContext:    true,
+		},
+		{
+			name:             "data attempted to be sent on the channel; channel read; context not canceled",
+			resizeStreamData: rawTerminalSize,
+			readFromChannel:  true,
+		},
+		{
+			name:          "no data attempted to be sent on the channel; context canceled",
+			cancelContext: true,
+		},
+		{
+			name: "no data attempted to be sent on the channel; context not canceled",
+		},
+	}
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			ctx, cancel := context.WithCancel(context.Background())
+			connCtx := connectionContext{
+				resizeStream: io.NopCloser(bytes.NewReader(testCase.resizeStreamData)),
+				resizeChan:   make(chan remotecommand.TerminalSize),
+			}
+
+			go handleResizeEvents(ctx, connCtx.resizeStream, connCtx.resizeChan)
+			if testCase.readFromChannel {
+				gotTerminalSize := <-connCtx.resizeChan
+				require.Equal(t, gotTerminalSize, testTerminalSize)
+			}
+			if testCase.cancelContext {
+				cancel()
+			}
+
+			goleak.VerifyNone(t)
+			cancel()
+		})
+	}
+}