Merge pull request #61705 from jstangroome/jstangroome-kubeadm-nodecidrmasksize

Automatic merge from submit-queue (batch tested with PRs 61705, 61609, 62103, 62113, 62115). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Support overriding the --node-cidr-mask-size arg passed to kube-controller-manager

Fixes: https://github.com/kubernetes/kubeadm/issues/724

**Release note**:
```release-note
kubeadm config can now override the Node CIDR Mask Size passed to kube-controller-manager.
```

cmd/kubeadm/app/phases/controlplane/manifests.go

@@ -321,15 +321,12 @@ func getControllerManagerCommand(cfg *kubeadmapi.MasterConfiguration, k8sVersion
 		defaultArguments["cluster-signing-cert-file"] = ""
 	}
 
-	command := []string{"kube-controller-manager"}
-	command = append(command, kubeadmutil.BuildArgumentListFromMap(defaultArguments, cfg.ControllerManagerExtraArgs)...)
-
 	if cfg.CloudProvider != "" {
-		command = append(command, "--cloud-provider="+cfg.CloudProvider)
+		defaultArguments["cloud-provider"] = cfg.CloudProvider
 
 		// Only append the --cloud-config option if there's a such file
 		if _, err := os.Stat(DefaultCloudConfigPath); err == nil {
-			command = append(command, "--cloud-config="+DefaultCloudConfigPath)
+			defaultArguments["cloud-config"] = DefaultCloudConfigPath
 		}
 	}
 
@@ -337,9 +334,14 @@ func getControllerManagerCommand(cfg *kubeadmapi.MasterConfiguration, k8sVersion
 	// Each node will get a subspace of the address CIDR provided with --pod-network-cidr.
 	if cfg.Networking.PodSubnet != "" {
 		maskSize := calcNodeCidrSize(cfg.Networking.PodSubnet)
-		command = append(command, "--allocate-node-cidrs=true", "--cluster-cidr="+cfg.Networking.PodSubnet,
+		defaultArguments["allocate-node-cidrs"] = "true"
-			"--node-cidr-mask-size="+maskSize)
+		defaultArguments["cluster-cidr"] = cfg.Networking.PodSubnet
+		defaultArguments["node-cidr-mask-size"] = maskSize
 	}
+
+	command := []string{"kube-controller-manager"}
+	command = append(command, kubeadmutil.BuildArgumentListFromMap(defaultArguments, cfg.ControllerManagerExtraArgs)...)
+
 	return command
 }
 

cmd/kubeadm/app/phases/controlplane/manifests_test.go

@@ -774,6 +774,29 @@ func TestGetControllerManagerCommand(t *testing.T) {
 				"--node-cidr-mask-size=24",
 			},
 		},
+		{
+			cfg: &kubeadmapi.MasterConfiguration{
+				Networking:                 kubeadmapi.Networking{PodSubnet: "10.0.1.15/16"},
+				ControllerManagerExtraArgs: map[string]string{"node-cidr-mask-size": "20"},
+				CertificatesDir:            testCertsDir,
+				KubernetesVersion:          "v1.7.0",
+			},
+			expected: []string{
+				"kube-controller-manager",
+				"--address=127.0.0.1",
+				"--leader-elect=true",
+				"--kubeconfig=" + kubeadmconstants.KubernetesDir + "/controller-manager.conf",
+				"--root-ca-file=" + testCertsDir + "/ca.crt",
+				"--service-account-private-key-file=" + testCertsDir + "/sa.key",
+				"--cluster-signing-cert-file=" + testCertsDir + "/ca.crt",
+				"--cluster-signing-key-file=" + testCertsDir + "/ca.key",
+				"--use-service-account-credentials=true",
+				"--controllers=*,bootstrapsigner,tokencleaner",
+				"--allocate-node-cidrs=true",
+				"--cluster-cidr=10.0.1.15/16",
+				"--node-cidr-mask-size=20",
+			},
+		},
 		{
 			cfg: &kubeadmapi.MasterConfiguration{
 				Networking:        kubeadmapi.Networking{PodSubnet: "2001:db8::/64"},