Handle null pointers for cli.StringSlice

Signed-off-by: Derek Nola <[email protected]>

Author: dereknola

pkg/agent/config/config.go

@@ -441,7 +441,7 @@ func get(ctx context.Context, envInfo *cmds.Agent, proxy proxy.Proxy) (*config.N
 	}
 	// If the supervisor and externally-facing apiserver are not on the same port, tell the proxy where to find the apiserver.
 	if controlConfig.SupervisorPort != controlConfig.HTTPSPort {
-		isIPv6 := utilsnet.IsIPv6(net.ParseIP(util.GetFirstValidIPString(envInfo.NodeIP)))
+		isIPv6 := utilsnet.IsIPv6(net.ParseIP(util.GetFirstValidIPString(&envInfo.NodeIP)))
 		if err := proxy.SetAPIServerPort(controlConfig.HTTPSPort, isIPv6); err != nil {
 			return nil, errors.Wrapf(err, "failed to set apiserver port to %d", controlConfig.HTTPSPort)
 		}
@@ -482,7 +482,7 @@ func get(ctx context.Context, envInfo *cmds.Agent, proxy proxy.Proxy) (*config.N
 	newNodePasswordFile := filepath.Join(nodeConfigPath, "password")
 	upgradeOldNodePasswordPath(oldNodePasswordFile, newNodePasswordFile)
 
-	nodeName, nodeIPs, err := util.GetHostnameAndIPs(envInfo.NodeName, envInfo.NodeIP)
+	nodeName, nodeIPs, err := util.GetHostnameAndIPs(envInfo.NodeName, &envInfo.NodeIP)
 	if err != nil {
 		return nil, err
 	}
@@ -536,7 +536,7 @@ func get(ctx context.Context, envInfo *cmds.Agent, proxy proxy.Proxy) (*config.N
 		}
 	}
 
-	nodeExternalIPs, err := util.ParseStringSliceToIPs(envInfo.NodeExternalIP)
+	nodeExternalIPs, err := util.ParseStringSliceToIPs(&envInfo.NodeExternalIP)
 	if err != nil {
 		return nil, fmt.Errorf("invalid node-external-ip: %w", err)
 	}

pkg/agent/run.go

@@ -335,7 +335,7 @@ func createProxyAndValidateToken(ctx context.Context, cfg *cmds.Agent) (proxy.Pr
 	if err := os.MkdirAll(agentDir, 0700); err != nil {
 		return nil, err
 	}
-	isIPv6 := utilsnet.IsIPv6(net.ParseIP(util.GetFirstValidIPString(cfg.NodeIP)))
+	isIPv6 := utilsnet.IsIPv6(net.ParseIP(util.GetFirstValidIPString(&cfg.NodeIP)))
 
 	proxy, err := proxy.NewSupervisorProxy(ctx, !cfg.DisableLoadBalancer, agentDir, cfg.ServerURL, cfg.LBServerPort, isIPv6)
 	if err != nil {

pkg/cli/server/server.go

@@ -252,13 +252,13 @@ func run(app *cli.Context, cfg *cmds.Server, leaderControllers server.CustomCont
 	}
 
 	if serverConfig.ControlConfig.PrivateIP == "" && len(cmds.AgentConfig.NodeIP.Value()) != 0 {
-		serverConfig.ControlConfig.PrivateIP = util.GetFirstValidIPString(cmds.AgentConfig.NodeIP)
+		serverConfig.ControlConfig.PrivateIP = util.GetFirstValidIPString(&cmds.AgentConfig.NodeIP)
 	}
 
 	// Ensure that we add the localhost name/ip and node name/ip to the SAN list. This list is shared by the
 	// certs for the supervisor, kube-apiserver cert, and etcd. DNS entries for the in-cluster kubernetes
 	// service endpoint are added later when the certificates are created.
-	nodeName, nodeIPs, err := util.GetHostnameAndIPs(cmds.AgentConfig.NodeName, cmds.AgentConfig.NodeIP)
+	nodeName, nodeIPs, err := util.GetHostnameAndIPs(cmds.AgentConfig.NodeName, &cmds.AgentConfig.NodeIP)
 	if err != nil {
 		return err
 	}
@@ -303,12 +303,12 @@ func run(app *cli.Context, cfg *cmds.Server, leaderControllers server.CustomCont
 
 		// if not set, try setting advertise-ip from agent node-external-ip
 		if serverConfig.ControlConfig.AdvertiseIP == "" && len(cmds.AgentConfig.NodeExternalIP.Value()) != 0 {
-			serverConfig.ControlConfig.AdvertiseIP = util.GetFirstValidIPString(cmds.AgentConfig.NodeExternalIP)
+			serverConfig.ControlConfig.AdvertiseIP = util.GetFirstValidIPString(&cmds.AgentConfig.NodeExternalIP)
 		}
 
 		// if not set, try setting advertise-ip from agent node-ip
 		if serverConfig.ControlConfig.AdvertiseIP == "" && len(cmds.AgentConfig.NodeIP.Value()) != 0 {
-			serverConfig.ControlConfig.AdvertiseIP = util.GetFirstValidIPString(cmds.AgentConfig.NodeIP)
+			serverConfig.ControlConfig.AdvertiseIP = util.GetFirstValidIPString(&cmds.AgentConfig.NodeIP)
 		}
 	}
 

pkg/util/net.go

@@ -137,7 +137,7 @@ func JoinIP6Nets(elems []*net.IPNet) string {
 // GetHostnameAndIPs takes a node name and list of IPs, usually from CLI args.
 // If set, these are used to return the node's name and addresses. If not set,
 // the system hostname and primary interface addresses are returned instead.
-func GetHostnameAndIPs(name string, nodeIPs cli.StringSlice) (string, []net.IP, error) {
+func GetHostnameAndIPs(name string, nodeIPs *cli.StringSlice) (string, []net.IP, error) {
 	ips := []net.IP{}
 	if len(nodeIPs.Value()) == 0 {
 		hostIP, err := apinet.ChooseHostInterface()
@@ -177,8 +177,11 @@ func GetHostnameAndIPs(name string, nodeIPs cli.StringSlice) (string, []net.IP,
 
 // ParseStringSliceToIPs converts slice of strings that in turn can be lists of comma separated unparsed IP addresses
 // into a single slice of net.IP, it returns error if at any point parsing failed
-func ParseStringSliceToIPs(s cli.StringSlice) ([]net.IP, error) {
+func ParseStringSliceToIPs(s *cli.StringSlice) ([]net.IP, error) {
 	var ips []net.IP
+	if s == nil {
+		return ips, nil
+	}
 	for _, unparsedIP := range s.Value() {
 		for _, v := range strings.Split(unparsedIP, ",") {
 			ip := net.ParseIP(v)
@@ -194,7 +197,10 @@ func ParseStringSliceToIPs(s cli.StringSlice) ([]net.IP, error) {
 
 // GetFirstValidIPString returns the first valid address from a list of IP address strings,
 // without preference for IP family. If no address are found, an empty string is returned.
-func GetFirstValidIPString(s cli.StringSlice) string {
+func GetFirstValidIPString(s *cli.StringSlice) string {
+	if s == nil {
+		return ""
+	}
 	for _, unparsedIP := range s.Value() {
 		for _, v := range strings.Split(unparsedIP, ",") {
 			if ip := net.ParseIP(v); ip != nil {

pkg/util/net_test.go

@@ -70,7 +70,7 @@ func Test_UnitParseStringSliceToIPs(t *testing.T) {
 	for _, tt := range tests {
 		t.Run(
 			tt.name, func(t *testing.T) {
-				got, err := ParseStringSliceToIPs(*tt.arg)
+				got, err := ParseStringSliceToIPs(tt.arg)
 				if (err != nil) != tt.wantErr {
 					t.Errorf("ParseStringSliceToIPs() error = %v, wantErr %v", err, tt.wantErr)
 					return