From dcef12f062575bfad927f201a1cc616dcfd94d2b Mon Sep 17 00:00:00 2001
From: Dillon Giacoppo <dillon.giacoppo@pm.me>
Date: Sun, 29 Jun 2025 11:44:16 +1000
Subject: [PATCH] fix(3643) add containerd-snapshotter support

---
 container/docker/factory.go | 24 ++++++++++++++++-------
 container/docker/handler.go | 38 ++++++++++++++++++++++++++++---------
 2 files changed, 46 insertions(+), 16 deletions(-)

diff --git a/container/docker/factory.go b/container/docker/factory.go
index 1c68b8625f..7e6a5cdbcc 100644
--- a/container/docker/factory.go
+++ b/container/docker/factory.go
@@ -25,6 +25,7 @@ import (
 
 	"github.com/blang/semver/v4"
 	dockersystem "github.com/docker/docker/api/types/system"
+	"github.com/google/cadvisor/container/containerd"
 
 	"github.com/google/cadvisor/container"
 	dockerutil "github.com/google/cadvisor/container/docker/utils"
@@ -94,12 +95,13 @@ func RootDir() string {
 type StorageDriver string
 
 const (
-	DevicemapperStorageDriver StorageDriver = "devicemapper"
-	AufsStorageDriver         StorageDriver = "aufs"
-	OverlayStorageDriver      StorageDriver = "overlay"
-	Overlay2StorageDriver     StorageDriver = "overlay2"
-	ZfsStorageDriver          StorageDriver = "zfs"
-	VfsStorageDriver          StorageDriver = "vfs"
+	DevicemapperStorageDriver          StorageDriver = "devicemapper"
+	AufsStorageDriver                  StorageDriver = "aufs"
+	OverlayStorageDriver               StorageDriver = "overlay"
+	Overlay2StorageDriver              StorageDriver = "overlay2"
+	ContainerdSnapshotterStorageDriver StorageDriver = "overlayfs"
+	ZfsStorageDriver                   StorageDriver = "zfs"
+	VfsStorageDriver                   StorageDriver = "vfs"
 )
 
 type dockerFactory struct {
@@ -108,7 +110,8 @@ type dockerFactory struct {
 	storageDriver StorageDriver
 	storageDir    string
 
-	client *docker.Client
+	client           *docker.Client
+	containerdClient containerd.ContainerdClient
 
 	// Information about the mounted cgroup subsystems.
 	cgroupSubsystems map[string]string
@@ -147,6 +150,7 @@ func (f *dockerFactory) NewContainerHandler(name string, metadataEnvAllowList []
 
 	handler, err = newDockerContainerHandler(
 		client,
+		f.containerdClient,
 		name,
 		f.machineInfoFactory,
 		f.fsInfo,
@@ -349,10 +353,16 @@ func Register(factory info.MachineInfoFactory, fsInfo fs.FsInfo, includedMetrics
 		}
 	}
 
+	containerdClient, err := containerd.Client(*containerd.ArgContainerdEndpoint, "moby")
+	if err != nil {
+		return fmt.Errorf("unable to create containerd client: %v", err)
+	}
+
 	klog.V(1).Infof("Registering Docker factory")
 	f := &dockerFactory{
 		cgroupSubsystems:   cgroupSubsystems,
 		client:             client,
+		containerdClient:   containerdClient,
 		dockerVersion:      dockerVersion,
 		dockerAPIVersion:   dockerAPIVersion,
 		fsInfo:             fsInfo,
diff --git a/container/docker/handler.go b/container/docker/handler.go
index 86ec729047..3f5593d2fc 100644
--- a/container/docker/handler.go
+++ b/container/docker/handler.go
@@ -16,6 +16,7 @@
 package docker
 
 import (
+	"encoding/json"
 	"fmt"
 	"os"
 	"path"
@@ -25,6 +26,8 @@ import (
 
 	"github.com/google/cadvisor/container"
 	"github.com/google/cadvisor/container/common"
+	"github.com/google/cadvisor/container/containerd"
+	"github.com/google/cadvisor/container/containerd/namespaces"
 	dockerutil "github.com/google/cadvisor/container/docker/utils"
 	containerlibcontainer "github.com/google/cadvisor/container/libcontainer"
 	"github.com/google/cadvisor/devicemapper"
@@ -32,6 +35,7 @@ import (
 	info "github.com/google/cadvisor/info/v1"
 	"github.com/google/cadvisor/zfs"
 	"github.com/opencontainers/cgroups"
+	"github.com/opencontainers/runtime-spec/specs-go"
 
 	docker "github.com/docker/docker/client"
 	"golang.org/x/net/context"
@@ -112,6 +116,7 @@ func getRwLayerID(containerID, storageDir string, sd StorageDriver, dockerVersio
 // newDockerContainerHandler returns a new container.ContainerHandler
 func newDockerContainerHandler(
 	client *docker.Client,
+	containerdClient containerd.ContainerdClient,
 	name string,
 	machineInfoFactory info.MachineInfoFactory,
 	fsInfo fs.FsInfo,
@@ -147,16 +152,31 @@ func newDockerContainerHandler(
 	// FIXME: Give `otherStorageDir` a more descriptive name.
 	otherStorageDir := path.Join(storageDir, pathToContainersDir, id)
 
-	rwLayerID, err := getRwLayerID(id, storageDir, storageDriver, dockerVersion)
-	if err != nil {
-		return nil, err
-	}
+	var rootfsStorageDir, zfsFilesystem, zfsParent string
+	if storageDriver == ContainerdSnapshotterStorageDriver {
+		ctx := namespaces.WithNamespace(context.Background(), "moby")
+		cntr, err := containerdClient.LoadContainer(ctx, id)
+		if err != nil {
+			return nil, err
+		}
 
-	// Determine the rootfs storage dir OR the pool name to determine the device.
-	// For devicemapper, we only need the thin pool name, and that is passed in to this call
-	rootfsStorageDir, zfsFilesystem, zfsParent, err := DetermineDeviceStorage(storageDriver, storageDir, rwLayerID)
-	if err != nil {
-		return nil, fmt.Errorf("unable to determine device storage: %v", err)
+		var spec specs.Spec
+		if err := json.Unmarshal(cntr.Spec.Value, &spec); err != nil {
+			return nil, err
+		}
+		rootfsStorageDir = spec.Root.Path
+	} else {
+		rwLayerID, err := getRwLayerID(id, storageDir, storageDriver, dockerVersion)
+		if err != nil {
+			return nil, err
+		}
+
+		// Determine the rootfs storage dir OR the pool name to determine the device.
+		// For devicemapper, we only need the thin pool name, and that is passed in to this call
+		rootfsStorageDir, zfsFilesystem, zfsParent, err = DetermineDeviceStorage(storageDriver, storageDir, rwLayerID)
+		if err != nil {
+			return nil, fmt.Errorf("unable to determine device storage: %v", err)
+		}
 	}
 
 	// We assume that if Inspect fails then the container is not known to docker.