dockershim: remove corrupt checkpoints immediately upon detection

hack/.golint_failures

@@ -174,7 +174,6 @@ pkg/kubelet/container/testing
 pkg/kubelet/custommetrics
 pkg/kubelet/dockershim
 pkg/kubelet/dockershim/cm
-pkg/kubelet/dockershim/errors
 pkg/kubelet/dockershim/libdocker
 pkg/kubelet/dockershim/remote
 pkg/kubelet/dockershim/testing

pkg/kubelet/dockershim/BUILD

@@ -47,7 +47,6 @@ go_library(
         "//pkg/kubelet/cm:go_default_library",
         "//pkg/kubelet/container:go_default_library",
         "//pkg/kubelet/dockershim/cm:go_default_library",
-        "//pkg/kubelet/dockershim/errors:go_default_library",
         "//pkg/kubelet/dockershim/libdocker:go_default_library",
         "//pkg/kubelet/dockershim/metrics:go_default_library",
         "//pkg/kubelet/leaky:go_default_library",
@@ -142,7 +141,6 @@ filegroup(
     srcs = [
         ":package-srcs",
         "//pkg/kubelet/dockershim/cm:all-srcs",
-        "//pkg/kubelet/dockershim/errors:all-srcs",
         "//pkg/kubelet/dockershim/libdocker:all-srcs",
         "//pkg/kubelet/dockershim/metrics:all-srcs",
         "//pkg/kubelet/dockershim/remote:all-srcs",

pkg/kubelet/dockershim/docker_checkpoint.go

@@ -23,7 +23,6 @@ import (
 	"path/filepath"
 
 	"github.com/golang/glog"
-	"k8s.io/kubernetes/pkg/kubelet/dockershim/errors"
 	utilstore "k8s.io/kubernetes/pkg/kubelet/util/store"
 	utilfs "k8s.io/kubernetes/pkg/util/filesystem"
 	hashutil "k8s.io/kubernetes/pkg/util/hash"
@@ -113,12 +112,14 @@ func (handler *PersistentCheckpointHandler) GetCheckpoint(podSandboxID string) (
 	//TODO: unmarhsal into a struct with just Version, check version, unmarshal into versioned type.
 	err = json.Unmarshal(blob, &checkpoint)
 	if err != nil {
-		glog.Errorf("Failed to unmarshal checkpoint %q. Checkpoint content: %q. ErrMsg: %v", podSandboxID, string(blob), err)
-		return &checkpoint, errors.CorruptCheckpointError
+		glog.Errorf("Failed to unmarshal checkpoint %q, removing checkpoint. Checkpoint content: %q. ErrMsg: %v", podSandboxID, string(blob), err)
+		handler.RemoveCheckpoint(podSandboxID)
+		return nil, fmt.Errorf("failed to unmarshal checkpoint")
 	}
 	if checkpoint.CheckSum != calculateChecksum(checkpoint) {
-		glog.Errorf("Checksum of checkpoint %q is not valid", podSandboxID)
-		return &checkpoint, errors.CorruptCheckpointError
+		glog.Errorf("Checksum of checkpoint %q is not valid, removing checkpoint", podSandboxID)
+		handler.RemoveCheckpoint(podSandboxID)
+		return nil, fmt.Errorf("checkpoint is corrupted")
 	}
 	return &checkpoint, nil
 }

pkg/kubelet/dockershim/docker_sandbox.go

@@ -30,7 +30,6 @@ import (
 	utilerrors "k8s.io/apimachinery/pkg/util/errors"
 	runtimeapi "k8s.io/kubernetes/pkg/kubelet/apis/cri/v1alpha1/runtime"
 	kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
-	"k8s.io/kubernetes/pkg/kubelet/dockershim/errors"
 	"k8s.io/kubernetes/pkg/kubelet/dockershim/libdocker"
 	"k8s.io/kubernetes/pkg/kubelet/qos"
 	"k8s.io/kubernetes/pkg/kubelet/types"
@@ -193,20 +192,10 @@ func (ds *dockerService) StopPodSandbox(podSandboxID string) error {
 		// actions will only have sandbox ID and not have pod namespace and name information.
 		// Return error if encounter any unexpected error.
 		if checkpointErr != nil {
-			if libdocker.IsContainerNotFoundError(statusErr) && checkpointErr == errors.CheckpointNotFoundError {
+			if libdocker.IsContainerNotFoundError(statusErr) {
 				glog.Warningf("Both sandbox container and checkpoint for id %q could not be found. "+
 					"Proceed without further sandbox information.", podSandboxID)
 			} else {
-				if checkpointErr == errors.CorruptCheckpointError {
-					// Remove the corrupted checkpoint so that the next
-					// StopPodSandbox call can proceed. This may indicate that
-					// some resources won't be reclaimed.
-					// TODO (#43021): Fix this properly.
-					glog.Warningf("Removing corrupted checkpoint %q: %+v", podSandboxID, *checkpoint)
-					if err := ds.checkpointHandler.RemoveCheckpoint(podSandboxID); err != nil {
-						glog.Warningf("Unable to remove corrupted checkpoint %q: %v", podSandboxID, err)
-					}
-				}
 				return utilerrors.NewAggregate([]error{
 					fmt.Errorf("failed to get checkpoint for sandbox %q: %v", podSandboxID, checkpointErr),
 					fmt.Errorf("failed to get sandbox status: %v", statusErr)})
@@ -488,13 +477,6 @@ func (ds *dockerService) ListPodSandbox(filter *runtimeapi.PodSandboxFilter) ([]
 		checkpoint, err := ds.checkpointHandler.GetCheckpoint(id)
 		if err != nil {
 			glog.Errorf("Failed to retrieve checkpoint for sandbox %q: %v", id, err)
-
-			if err == errors.CorruptCheckpointError {
-				glog.Warningf("Removing corrupted checkpoint %q: %+v", id, *checkpoint)
-				if err := ds.checkpointHandler.RemoveCheckpoint(id); err != nil {
-					glog.Warningf("Unable to remove corrupted checkpoint %q: %v", id, err)
-				}
-			}
 			continue
 		}
 		result = append(result, checkpointToRuntimeAPISandbox(id, checkpoint))

pkg/kubelet/dockershim/docker_service.go

@@ -38,7 +38,6 @@ import (
 	kubecm "k8s.io/kubernetes/pkg/kubelet/cm"
 	kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
 	"k8s.io/kubernetes/pkg/kubelet/dockershim/cm"
-	"k8s.io/kubernetes/pkg/kubelet/dockershim/errors"
 	"k8s.io/kubernetes/pkg/kubelet/network"
 	"k8s.io/kubernetes/pkg/kubelet/network/cni"
 	"k8s.io/kubernetes/pkg/kubelet/network/hostport"
@@ -366,10 +365,6 @@ func (ds *dockerService) GetPodPortMappings(podSandboxID string) ([]*hostport.Po
 	checkpoint, err := ds.checkpointHandler.GetCheckpoint(podSandboxID)
 	// Return empty portMappings if checkpoint is not found
 	if err != nil {
-		if err == errors.CheckpointNotFoundError {
-			glog.Warningf("Failed to retrieve checkpoint for sandbox %q: %v", podSandboxID, err)
-			return nil, nil
-		}
 		return nil, err
 	}
 

pkg/kubelet/dockershim/errors/BUILD

-package(default_visibility = ["//visibility:public"])
-
-load(
-    "@io_bazel_rules_go//go:def.bzl",
-    "go_library",
-)
-
-go_library(
-    name = "go_default_library",
-    srcs = ["errors.go"],
-    importpath = "k8s.io/kubernetes/pkg/kubelet/dockershim/errors",
-)
-
-filegroup(
-    name = "package-srcs",
-    srcs = glob(["**"]),
-    tags = ["automanaged"],
-    visibility = ["//visibility:private"],
-)
-
-filegroup(
-    name = "all-srcs",
-    srcs = [":package-srcs"],
-    tags = ["automanaged"],
-)

pkg/kubelet/dockershim/errors/errors.go

-/*
-Copyright 2017 The Kubernetes Authors.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-package errors
-
-import "fmt"
-
-var CorruptCheckpointError = fmt.Errorf("checkpoint is corrupted.")
-var CheckpointNotFoundError = fmt.Errorf("checkpoint is not found.")

pkg/kubelet/dockershim/testing/BUILD

@@ -9,7 +9,6 @@ go_library(
     name = "go_default_library",
     srcs = ["util.go"],
     importpath = "k8s.io/kubernetes/pkg/kubelet/dockershim/testing",
-    deps = ["//pkg/kubelet/dockershim/errors:go_default_library"],
 )
 
 filegroup(

pkg/kubelet/dockershim/testing/util.go

@@ -17,9 +17,8 @@ limitations under the License.
 package testing
 
 import (
+	"fmt"
 	"sync"
-
-	"k8s.io/kubernetes/pkg/kubelet/dockershim/errors"
 )
 
 // MemStore is an implementation of CheckpointStore interface which stores checkpoint in memory.
@@ -44,7 +43,7 @@ func (mstore *MemStore) Read(key string) ([]byte, error) {
 	defer mstore.Unlock()
 	data, ok := mstore.mem[key]
 	if !ok {
-		return nil, errors.CheckpointNotFoundError
+		return nil, fmt.Errorf("checkpoint is not found")
 	}
 	return data, nil
 }