Fix cleanup context.

Signed-off-by: Lantao Liu <lantaol@google.com>

pkg/containerd/importer/importer.go

@@ -36,6 +36,7 @@ import (
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/pkg/errors"
 
+	ctrdutil "github.com/containerd/cri-containerd/pkg/containerd/util"
 	"github.com/containerd/cri-containerd/pkg/util"
 )
 
@@ -80,6 +81,7 @@ func Import(ctx context.Context, client *containerd.Client, reader io.Reader) (_
 	if err != nil {
 		return nil, err
 	}
+	// TODO(random-liu): Fix this after containerd client is fixed (containerd/containerd#2193)
 	defer done() // nolint: errcheck
 
 	cs := client.ContentStore()
@@ -134,9 +136,13 @@ func Import(ctx context.Context, client *containerd.Client, reader io.Reader) (_
 		// TODO(random-liu): Consider whether we should keep images already imported
 		// even when there is an error.
 		for _, ref := range refs {
-			if err := is.Delete(ctx, ref); err != nil {
-				log.G(ctx).WithError(err).Errorf("Failed to remove image %q", ref)
-			}
+			func() {
+				deferCtx, deferCancel := ctrdutil.DeferContext()
+				defer deferCancel()
+				if err := is.Delete(deferCtx, ref); err != nil {
+					log.G(ctx).WithError(err).Errorf("Failed to remove image %q", ref)
+				}
+			}()
 		}
 	}()
 	for _, mfst := range mfsts {

pkg/containerd/util/util.go

@@ -0,0 +1,35 @@
+/*
+Copyright 2018 The containerd 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 util
+
+import (
+	"time"
+
+	"golang.org/x/net/context"
+)
+
+// deferCleanupTimeout is the default timeout for containerd cleanup operations
+// in defer.
+const deferCleanupTimeout = 1 * time.Minute
+
+// DeferContext returns a context for containerd cleanup operations in defer.
+// A default timeout is applied to avoid cleanup operation pending forever.
+// TODO(random-liu): Add namespace after local services are used.
+// (containerd/containerd#2183)
+func DeferContext() (context.Context, context.CancelFunc) {
+	return context.WithTimeout(context.Background(), deferCleanupTimeout)
+}