From 7a0690cd592f6ae797a71c8757603a20defcbe41 Mon Sep 17 00:00:00 2001
From: Ted Yu <yute@vmware.com>
Date: Mon, 10 Feb 2020 09:41:09 -0800
Subject: [PATCH] Use ProxierHealthUpdater directly to avoid panic

---
 cmd/kube-proxy/app/server.go            |  2 +-
 cmd/kube-proxy/app/server_others.go     |  2 +-
 cmd/kube-proxy/app/server_windows.go    |  2 +-
 pkg/proxy/healthcheck/proxier_health.go | 23 +++++++++++++----------
 4 files changed, 16 insertions(+), 13 deletions(-)

diff --git a/cmd/kube-proxy/app/server.go b/cmd/kube-proxy/app/server.go
index 1f87fc53d59..033c297d15c 100644
--- a/cmd/kube-proxy/app/server.go
+++ b/cmd/kube-proxy/app/server.go
@@ -532,7 +532,7 @@ type ProxyServer struct {
 	UseEndpointSlices      bool
 	OOMScoreAdj            *int32
 	ConfigSyncPeriod       time.Duration
-	HealthzServer          *healthcheck.ProxierHealthServer
+	HealthzServer          healthcheck.ProxierHealthUpdater
 }
 
 // createClients creates a kube client and an event client from the given config and masterOverride.
diff --git a/cmd/kube-proxy/app/server_others.go b/cmd/kube-proxy/app/server_others.go
index 87e3ea3866c..23c977007f8 100644
--- a/cmd/kube-proxy/app/server_others.go
+++ b/cmd/kube-proxy/app/server_others.go
@@ -130,7 +130,7 @@ func newProxyServer(
 		Namespace: "",
 	}
 
-	var healthzServer *healthcheck.ProxierHealthServer
+	var healthzServer healthcheck.ProxierHealthUpdater
 	if len(config.HealthzBindAddress) > 0 {
 		healthzServer = healthcheck.NewProxierHealthServer(config.HealthzBindAddress, 2*config.IPTables.SyncPeriod.Duration, recorder, nodeRef)
 	}
diff --git a/cmd/kube-proxy/app/server_windows.go b/cmd/kube-proxy/app/server_windows.go
index f94ec6c5297..a2e6d2c63e0 100644
--- a/cmd/kube-proxy/app/server_windows.go
+++ b/cmd/kube-proxy/app/server_windows.go
@@ -92,7 +92,7 @@ func newProxyServer(config *proxyconfigapi.KubeProxyConfiguration, cleanupAndExi
 		Namespace: "",
 	}
 
-	var healthzServer *healthcheck.ProxierHealthServer
+	var healthzServer healthcheck.ProxierHealthUpdater
 	if len(config.HealthzBindAddress) > 0 {
 		healthzServer = healthcheck.NewProxierHealthServer(config.HealthzBindAddress, 2*config.IPTables.SyncPeriod.Duration, recorder, nodeRef)
 	}
diff --git a/pkg/proxy/healthcheck/proxier_health.go b/pkg/proxy/healthcheck/proxier_health.go
index e9a0002304a..afeb4fff657 100644
--- a/pkg/proxy/healthcheck/proxier_health.go
+++ b/pkg/proxy/healthcheck/proxier_health.go
@@ -42,13 +42,16 @@ type ProxierHealthUpdater interface {
 	// Updated should be called when the proxier has successfully updated the service
 	// rules to reflect the current state.
 	Updated()
+
+	// Run starts the healthz http server and returns.
+	Run()
 }
 
-var _ ProxierHealthUpdater = &ProxierHealthServer{}
+var _ ProxierHealthUpdater = &proxierHealthServer{}
 
-// ProxierHealthServer returns 200 "OK" by default. It verifies that the delay between
+// proxierHealthServer returns 200 "OK" by default. It verifies that the delay between
 // QueuedUpdate() calls and Updated() calls never exceeds healthTimeout.
-type ProxierHealthServer struct {
+type proxierHealthServer struct {
 	listener    listener
 	httpFactory httpServerFactory
 	clock       clock.Clock
@@ -63,12 +66,12 @@ type ProxierHealthServer struct {
 }
 
 // NewProxierHealthServer returns a proxier health http server.
-func NewProxierHealthServer(addr string, healthTimeout time.Duration, recorder record.EventRecorder, nodeRef *v1.ObjectReference) *ProxierHealthServer {
+func NewProxierHealthServer(addr string, healthTimeout time.Duration, recorder record.EventRecorder, nodeRef *v1.ObjectReference) ProxierHealthUpdater {
 	return newProxierHealthServer(stdNetListener{}, stdHTTPServerFactory{}, clock.RealClock{}, addr, healthTimeout, recorder, nodeRef)
 }
 
-func newProxierHealthServer(listener listener, httpServerFactory httpServerFactory, c clock.Clock, addr string, healthTimeout time.Duration, recorder record.EventRecorder, nodeRef *v1.ObjectReference) *ProxierHealthServer {
-	return &ProxierHealthServer{
+func newProxierHealthServer(listener listener, httpServerFactory httpServerFactory, c clock.Clock, addr string, healthTimeout time.Duration, recorder record.EventRecorder, nodeRef *v1.ObjectReference) *proxierHealthServer {
+	return &proxierHealthServer{
 		listener:      listener,
 		httpFactory:   httpServerFactory,
 		clock:         c,
@@ -80,17 +83,17 @@ func newProxierHealthServer(listener listener, httpServerFactory httpServerFacto
 }
 
 // Updated updates the lastUpdated timestamp.
-func (hs *ProxierHealthServer) Updated() {
+func (hs *proxierHealthServer) Updated() {
 	hs.lastUpdated.Store(hs.clock.Now())
 }
 
 // QueuedUpdate updates the lastQueued timestamp.
-func (hs *ProxierHealthServer) QueuedUpdate() {
+func (hs *proxierHealthServer) QueuedUpdate() {
 	hs.lastQueued.Store(hs.clock.Now())
 }
 
 // Run starts the healthz http server and returns.
-func (hs *ProxierHealthServer) Run() {
+func (hs *proxierHealthServer) Run() {
 	serveMux := http.NewServeMux()
 	serveMux.Handle("/healthz", healthzHandler{hs: hs})
 	server := hs.httpFactory.New(hs.addr, serveMux)
@@ -117,7 +120,7 @@ func (hs *ProxierHealthServer) Run() {
 }
 
 type healthzHandler struct {
-	hs *ProxierHealthServer
+	hs *proxierHealthServer
 }
 
 func (h healthzHandler) ServeHTTP(resp http.ResponseWriter, req *http.Request) {