From 8118636321ae09d99fbd5328b9c8245f255807b3 Mon Sep 17 00:00:00 2001
From: HirazawaUi <695097494plus@gmail.com>
Date: Thu, 4 Sep 2025 22:36:41 +0800
Subject: [PATCH] Close container runtime connections after use

---
 cmd/kubeadm/app/cmd/config.go                   |  1 +
 cmd/kubeadm/app/cmd/phases/reset/cleanupnode.go |  2 ++
 cmd/kubeadm/app/preflight/checks.go             |  2 ++
 cmd/kubeadm/app/util/runtime/runtime.go         | 15 +++++++++++++++
 4 files changed, 20 insertions(+)

diff --git a/cmd/kubeadm/app/cmd/config.go b/cmd/kubeadm/app/cmd/config.go
index 3907b0651f0..be8d486b531 100644
--- a/cmd/kubeadm/app/cmd/config.go
+++ b/cmd/kubeadm/app/cmd/config.go
@@ -387,6 +387,7 @@ func newCmdConfigImagesPull() *cobra.Command {
 			if err := containerRuntime.Connect(); err != nil {
 				return err
 			}
+			defer containerRuntime.Close()
 			return PullControlPlaneImages(containerRuntime, &internalcfg.ClusterConfiguration)
 		},
 		Args: cobra.NoArgs,
diff --git a/cmd/kubeadm/app/cmd/phases/reset/cleanupnode.go b/cmd/kubeadm/app/cmd/phases/reset/cleanupnode.go
index 3a8a769edc4..8a163a1686e 100644
--- a/cmd/kubeadm/app/cmd/phases/reset/cleanupnode.go
+++ b/cmd/kubeadm/app/cmd/phases/reset/cleanupnode.go
@@ -138,6 +138,8 @@ func removeContainers(criSocketPath string) error {
 	if err := containerRuntime.Connect(); err != nil {
 		return err
 	}
+	defer containerRuntime.Close()
+
 	containers, err := containerRuntime.ListKubeContainers()
 	if err != nil {
 		return err
diff --git a/cmd/kubeadm/app/preflight/checks.go b/cmd/kubeadm/app/preflight/checks.go
index 36978405d19..b8030f7a636 100644
--- a/cmd/kubeadm/app/preflight/checks.go
+++ b/cmd/kubeadm/app/preflight/checks.go
@@ -84,6 +84,7 @@ func (ContainerRuntimeCheck) Name() string {
 // Check validates the container runtime
 func (crc ContainerRuntimeCheck) Check() (warnings, errorList []error) {
 	klog.V(1).Infoln("validating the container runtime")
+	defer crc.runtime.Close()
 	if err := crc.runtime.IsRunning(); err != nil {
 		errorList = append(errorList, err)
 	}
@@ -1087,6 +1088,7 @@ func RunPullImagesCheck(execer utilsexec.Interface, cfg *kubeadmapi.InitConfigur
 	if err := containerRuntime.Connect(); err != nil {
 		return handleError(os.Stderr, err.Error())
 	}
+	defer containerRuntime.Close()
 
 	serialPull := true
 	if cfg.NodeRegistration.ImagePullSerial != nil {
diff --git a/cmd/kubeadm/app/util/runtime/runtime.go b/cmd/kubeadm/app/util/runtime/runtime.go
index 851af6f844a..826330cda94 100644
--- a/cmd/kubeadm/app/util/runtime/runtime.go
+++ b/cmd/kubeadm/app/util/runtime/runtime.go
@@ -42,6 +42,7 @@ var defaultKnownCRISockets = []string{
 // ContainerRuntime is an interface for working with container runtimes
 type ContainerRuntime interface {
 	Connect() error
+	Close()
 	SetImpl(impl)
 	IsRunning() error
 	ListKubeContainers() ([]string, error)
@@ -93,6 +94,20 @@ func (runtime *CRIRuntime) Connect() error {
 	return nil
 }
 
+// Close closes the connections to the runtime and image services.
+func (runtime *CRIRuntime) Close() {
+	if runtime.runtimeService != nil {
+		if err := runtime.runtimeService.Close(); err != nil {
+			klog.Warningf("failed to close runtime service: %v", err)
+		}
+	}
+	if runtime.imageService != nil {
+		if err := runtime.imageService.Close(); err != nil {
+			klog.Warningf("failed to close image service: %v", err)
+		}
+	}
+}
+
 // IsRunning checks if runtime is running.
 func (runtime *CRIRuntime) IsRunning() error {
 	ctx, cancel := defaultContext()