From 2ba178c92c19bad48da800e106c73a50f742fc0d Mon Sep 17 00:00:00 2001
From: SataQiu <shidaqiu2018@gmail.com>
Date: Mon, 1 Mar 2021 11:19:47 +0800
Subject: [PATCH] kubeadm: skip validating pod subnet against node-cidr-mask
 when allocate-node-cidrs is set to be false

---
 .../app/apis/kubeadm/validation/validation.go |  6 ++--
 .../app/phases/controlplane/manifests_test.go | 35 +++++++++++++++++++
 2 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/cmd/kubeadm/app/apis/kubeadm/validation/validation.go b/cmd/kubeadm/app/apis/kubeadm/validation/validation.go
index 91297ed8624..d2c19ed6811 100644
--- a/cmd/kubeadm/app/apis/kubeadm/validation/validation.go
+++ b/cmd/kubeadm/app/apis/kubeadm/validation/validation.go
@@ -501,8 +501,10 @@ func ValidateNetworking(c *kubeadm.ClusterConfiguration, fldPath *field.Path) fi
 	}
 	if len(c.Networking.PodSubnet) != 0 {
 		allErrs = append(allErrs, ValidateIPNetFromString(c.Networking.PodSubnet, constants.MinimumAddressesInPodSubnet, isDualStack, field.NewPath("podSubnet"))...)
-		// Pod subnet was already validated, we need to validate now against the node-mask
-		allErrs = append(allErrs, ValidatePodSubnetNodeMask(c.Networking.PodSubnet, c, field.NewPath("podSubnet"))...)
+		if c.ControllerManager.ExtraArgs["allocate-node-cidrs"] != "false" {
+			// Pod subnet was already validated, we need to validate now against the node-mask
+			allErrs = append(allErrs, ValidatePodSubnetNodeMask(c.Networking.PodSubnet, c, field.NewPath("podSubnet"))...)
+		}
 	}
 	return allErrs
 }
diff --git a/cmd/kubeadm/app/phases/controlplane/manifests_test.go b/cmd/kubeadm/app/phases/controlplane/manifests_test.go
index ee45269e9e6..337ba52149e 100644
--- a/cmd/kubeadm/app/phases/controlplane/manifests_test.go
+++ b/cmd/kubeadm/app/phases/controlplane/manifests_test.go
@@ -765,6 +765,41 @@ func TestGetControllerManagerCommand(t *testing.T) {
 				"--service-cluster-ip-range=fd03::/112",
 			},
 		},
+		{
+			name: "IPv6 networking custom extra-args for " + cpVersion,
+			cfg: &kubeadmapi.ClusterConfiguration{
+				Networking: kubeadmapi.Networking{
+					PodSubnet:     "2001:db8::/64",
+					ServiceSubnet: "fd03::/112",
+					DNSDomain:     "cluster.local",
+				},
+				ControllerManager: kubeadmapi.ControlPlaneComponent{
+					ExtraArgs: map[string]string{"allocate-node-cidrs": "false"},
+				},
+				CertificatesDir:   testCertsDir,
+				KubernetesVersion: cpVersion,
+			},
+			expected: []string{
+				"kube-controller-manager",
+				"--port=0",
+				"--bind-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",
+				"--authentication-kubeconfig=" + kubeadmconstants.KubernetesDir + "/controller-manager.conf",
+				"--authorization-kubeconfig=" + kubeadmconstants.KubernetesDir + "/controller-manager.conf",
+				"--client-ca-file=" + testCertsDir + "/ca.crt",
+				"--requestheader-client-ca-file=" + testCertsDir + "/front-proxy-ca.crt",
+				"--allocate-node-cidrs=false",
+				"--cluster-cidr=2001:db8::/64",
+				"--service-cluster-ip-range=fd03::/112",
+			},
+		},
 		{
 			name: "dual-stack networking for " + cpVersion,
 			cfg: &kubeadmapi.ClusterConfiguration{