kubernetes/pkg/kubelet/userns/userns_manager_test.go
Rodrigo Campos 2508f468a8 kubelet/userns: Add more unit tests
This covers all public methods and overall test coverage is above 80%
again.

Signed-off-by: Rodrigo Campos <rodrigoca@microsoft.com>
2023-10-18 11:59:54 +02:00

362 lines
12 KiB
Go

/*
Copyright 2022 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 userns
import (
"fmt"
"testing"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
v1 "k8s.io/api/core/v1"
metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
"k8s.io/apimachinery/pkg/types"
utilfeature "k8s.io/apiserver/pkg/util/feature"
featuregatetesting "k8s.io/component-base/featuregate/testing"
runtimeapi "k8s.io/cri-api/pkg/apis/runtime/v1"
pkgfeatures "k8s.io/kubernetes/pkg/features"
kubecontainer "k8s.io/kubernetes/pkg/kubelet/container"
)
type testUserNsPodsManager struct {
podDir string
podList []types.UID
}
func (m *testUserNsPodsManager) GetPodDir(podUID types.UID) string {
if m.podDir == "" {
return "/tmp/non-existant-dir.This-is-not-used-in-tests"
}
return m.podDir
}
func (m *testUserNsPodsManager) ListPodsFromDisk() ([]types.UID, error) {
if len(m.podList) == 0 {
return nil, nil
}
return m.podList, nil
}
func TestUserNsManagerAllocate(t *testing.T) {
defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, pkgfeatures.UserNamespacesSupport, true)()
testUserNsPodsManager := &testUserNsPodsManager{}
m, err := MakeUserNsManager(testUserNsPodsManager)
require.NoError(t, err)
assert.Equal(t, true, m.isSet(0*65536), "m.isSet(0) should be true")
allocated, length, err := m.allocateOne("one")
assert.NoError(t, err)
assert.Equal(t, userNsLength, int(length), "m.isSet(%d).length=%v", allocated, length)
assert.Equal(t, true, m.isSet(allocated), "m.isSet(%d)", allocated)
allocated2, length2, err := m.allocateOne("two")
assert.NoError(t, err)
assert.NotEqual(t, allocated, allocated2, "allocated != allocated2")
assert.Equal(t, length, length2, "length == length2")
// verify that re-adding the same pod with the same settings won't fail
err = m.record("two", allocated2, length2)
assert.NoError(t, err)
// but it fails if anyting is different
err = m.record("two", allocated2+1, length2)
assert.Error(t, err)
m.Release("one")
m.Release("two")
assert.Equal(t, false, m.isSet(allocated), "m.isSet(%d)", allocated)
assert.Equal(t, false, m.isSet(allocated2), "m.nsSet(%d)", allocated2)
var allocs []uint32
for i := 0; i < 1000; i++ {
allocated, length, err = m.allocateOne(types.UID(fmt.Sprintf("%d", i)))
assert.Equal(t, userNsLength, int(length), "length is not the expected. iter: %v", i)
assert.NoError(t, err)
allocs = append(allocs, allocated)
}
for i, v := range allocs {
assert.Equal(t, true, m.isSet(v), "m.isSet(%d) should be true", v)
m.Release(types.UID(fmt.Sprintf("%d", i)))
assert.Equal(t, false, m.isSet(v), "m.isSet(%d) should be false", v)
err = m.record(types.UID(fmt.Sprintf("%d", i)), v, userNsLength)
assert.NoError(t, err)
m.Release(types.UID(fmt.Sprintf("%d", i)))
assert.Equal(t, false, m.isSet(v), "m.isSet(%d) should be false", v)
}
}
func TestUserNsManagerParseUserNsFile(t *testing.T) {
defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, pkgfeatures.UserNamespacesSupport, true)()
cases := []struct {
name string
file string
success bool
}{
{
name: "basic",
file: `{
"uidMappings":[ { "hostId":131072, "containerId":0, "length":65536 } ],
"gidMappings":[ { "hostId":131072, "containerId":0, "length":65536 } ]
}`,
success: true,
},
{
name: "invalid length",
file: `{
"uidMappings":[ { "hostId":131072, "containerId":0, "length":0 } ],
"gidMappings":[ { "hostId":131072, "containerId":0, "length":0 } ]
}`,
success: false,
},
{
name: "wrong offset",
file: `{
"uidMappings":[ {"hostId":131072, "containerId":0, "length":65536 } ],
"gidMappings":[ {"hostId":1, "containerId":0, "length":65536 } ]
}`,
success: false,
},
{
name: "two GID mappings",
file: `{
"uidMappings":[ { "hostId":131072, "containerId":0, "length":userNsLength } ],
"gidMappings":[ { "hostId":131072, "containerId":0, "length":userNsLength }, { "hostId":196608, "containerId":0, "length":65536 } ]
}`,
success: false,
},
{
name: "two UID mappings",
file: `{
"uidMappings":[ { "hostId":131072, "containerId":0, "length":65536 }, { "hostId":196608, "containerId":0, "length":65536 } ],
"gidMappings":[ { "hostId":131072, "containerId":0, "length":65536 } ]
}`,
success: false,
},
{
name: "no root UID",
file: `{
"uidMappings":[ { "hostId":131072, "containerId":1, "length":65536 } ],
"gidMappings":[ { "hostId":131072, "containerId":0, "length":65536 } ]
}`,
success: false,
},
{
name: "no root GID",
file: `{
"uidMappings":[ { "hostId":131072, "containerId":0, "length":65536 } ],
"gidMappings":[ { "hostId":131072, "containerId":1, "length":65536 } ]
}`,
success: false,
},
}
testUserNsPodsManager := &testUserNsPodsManager{}
m, err := MakeUserNsManager(testUserNsPodsManager)
assert.NoError(t, err)
for _, tc := range cases {
t.Run(tc.name, func(t *testing.T) {
// We don't validate the result. It was parsed with the json parser, we trust that.
_, err = m.parseUserNsFileAndRecord(types.UID(tc.name), []byte(tc.file))
if (tc.success && err == nil) || (!tc.success && err != nil) {
return
}
t.Errorf("expected success: %v but got error: %v", tc.success, err)
})
}
}
func TestGetOrCreateUserNamespaceMappings(t *testing.T) {
defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, pkgfeatures.UserNamespacesSupport, true)()
trueVal := true
falseVal := false
cases := []struct {
name string
pod *v1.Pod
expMode runtimeapi.NamespaceMode
success bool
}{
{
name: "no user namespace",
pod: &v1.Pod{},
expMode: runtimeapi.NamespaceMode_NODE,
success: true,
},
{
name: "opt-in to host user namespace",
pod: &v1.Pod{
Spec: v1.PodSpec{
HostUsers: &trueVal,
},
},
expMode: runtimeapi.NamespaceMode_NODE,
success: true,
},
{
name: "user namespace",
pod: &v1.Pod{
Spec: v1.PodSpec{
HostUsers: &falseVal,
},
},
expMode: runtimeapi.NamespaceMode_POD,
success: true,
},
}
for _, tc := range cases {
t.Run(tc.name, func(t *testing.T) {
// These tests will create the userns file, so use an existing podDir.
testUserNsPodsManager := &testUserNsPodsManager{podDir: t.TempDir()}
m, err := MakeUserNsManager(testUserNsPodsManager)
assert.NoError(t, err)
userns, err := m.GetOrCreateUserNamespaceMappings(tc.pod)
if (tc.success && err != nil) || (!tc.success && err == nil) {
t.Errorf("expected success: %v but got error: %v", tc.success, err)
}
if userns.GetMode() != tc.expMode {
t.Errorf("expected mode: %v but got: %v", tc.expMode, userns.GetMode())
}
})
}
}
func TestCleanupOrphanedPodUsernsAllocations(t *testing.T) {
defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, pkgfeatures.UserNamespacesSupport, true)()
cases := []struct {
name string
runningPods []*kubecontainer.Pod
pods []*v1.Pod
listPods []types.UID /* pods to list */
podSetBeforeCleanup []types.UID /* pods to record before cleanup */
podSetAfterCleanup []types.UID /* pods set expected after cleanup */
podUnsetAfterCleanup []types.UID /* pods set expected after cleanup */
}{
{
name: "no stale pods",
listPods: []types.UID{"pod-1", "pod-2"},
},
{
name: "no stale pods set",
podSetBeforeCleanup: []types.UID{"pod-1", "pod-2"},
listPods: []types.UID{"pod-1", "pod-2"},
podUnsetAfterCleanup: []types.UID{"pod-1", "pod-2"},
},
{
name: "one running pod",
listPods: []types.UID{"pod-1", "pod-2"},
podSetBeforeCleanup: []types.UID{"pod-1", "pod-2"},
runningPods: []*kubecontainer.Pod{{ID: "pod-1"}},
podSetAfterCleanup: []types.UID{"pod-1"},
podUnsetAfterCleanup: []types.UID{"pod-2"},
},
{
name: "pod set before cleanup but not listed ==> unset",
podSetBeforeCleanup: []types.UID{"pod-1", "pod-2"},
runningPods: []*kubecontainer.Pod{{ID: "pod-1"}},
podUnsetAfterCleanup: []types.UID{"pod-1", "pod-2"},
},
{
name: "one pod",
listPods: []types.UID{"pod-1", "pod-2"},
podSetBeforeCleanup: []types.UID{"pod-1", "pod-2"},
pods: []*v1.Pod{{ObjectMeta: metav1.ObjectMeta{UID: "pod-1"}}},
podSetAfterCleanup: []types.UID{"pod-1"},
podUnsetAfterCleanup: []types.UID{"pod-2"},
},
{
name: "no listed pods ==> all unset",
podSetBeforeCleanup: []types.UID{"pod-1", "pod-2"},
podUnsetAfterCleanup: []types.UID{"pod-1", "pod-2"},
},
}
for _, tc := range cases {
t.Run(tc.name, func(t *testing.T) {
testUserNsPodsManager := &testUserNsPodsManager{
podList: tc.listPods,
}
m, err := MakeUserNsManager(testUserNsPodsManager)
require.NoError(t, err)
// Record the userns range as used
for i, pod := range tc.podSetBeforeCleanup {
err := m.record(pod, uint32((i+1)*65536), 65536)
require.NoError(t, err)
}
err = m.CleanupOrphanedPodUsernsAllocations(tc.pods, tc.runningPods)
require.NoError(t, err)
for _, pod := range tc.podSetAfterCleanup {
ok := m.podAllocated(pod)
assert.True(t, ok, "pod %q should be allocated", pod)
}
for _, pod := range tc.podUnsetAfterCleanup {
ok := m.podAllocated(pod)
assert.False(t, ok, "pod %q should not be allocated", pod)
}
})
}
}
func TestAllocateMaxPods(t *testing.T) {
defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, pkgfeatures.UserNamespacesSupport, true)()
testUserNsPodsManager := &testUserNsPodsManager{}
m, err := MakeUserNsManager(testUserNsPodsManager)
require.NoError(t, err)
// The first maxPods allocations should succeed.
for i := 0; i < maxPods; i++ {
_, _, err = m.allocateOne(types.UID(fmt.Sprintf("%d", i)))
require.NoError(t, err)
}
// The next allocation should fail, hitting maxPods.
_, _, err = m.allocateOne(types.UID(fmt.Sprintf("%d", maxPods+1)))
assert.Error(t, err)
}
func TestRecordMaxPods(t *testing.T) {
defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, pkgfeatures.UserNamespacesSupport, true)()
testUserNsPodsManager := &testUserNsPodsManager{}
m, err := MakeUserNsManager(testUserNsPodsManager)
require.NoError(t, err)
// The first maxPods allocations should succeed.
for i := 0; i < maxPods; i++ {
err = m.record(types.UID(fmt.Sprintf("%d", i)), uint32((i+1)*65536), 65536)
require.NoError(t, err)
}
// The next allocation should fail, hitting maxPods.
err = m.record(types.UID(fmt.Sprintf("%d", maxPods+1)), uint32((maxPods+1)*65536), 65536)
assert.Error(t, err)
}