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// Copyright 2018 The gVisor 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 container creates and manipulates containers.
package container
import (
"bufio"
"context"
"errors"
"fmt"
"io/ioutil"
"os"
"os/exec"
"path"
"regexp"
"strconv"
"strings"
"syscall"
"time"
"github.com/cenkalti/backoff"
specs "github.com/opencontainers/runtime-spec/specs-go"
"golang.org/x/sys/unix"
"gvisor.dev/gvisor/pkg/abi/linux"
"gvisor.dev/gvisor/pkg/cleanup"
"gvisor.dev/gvisor/pkg/log"
"gvisor.dev/gvisor/pkg/sentry/control"
"gvisor.dev/gvisor/pkg/sentry/fsimpl/erofs"
"gvisor.dev/gvisor/pkg/sentry/fsimpl/tmpfs"
"gvisor.dev/gvisor/pkg/sentry/pgalloc"
"gvisor.dev/gvisor/pkg/sighandling"
"gvisor.dev/gvisor/pkg/state/statefile"
"gvisor.dev/gvisor/runsc/boot"
"gvisor.dev/gvisor/runsc/cgroup"
"gvisor.dev/gvisor/runsc/config"
"gvisor.dev/gvisor/runsc/console"
"gvisor.dev/gvisor/runsc/donation"
"gvisor.dev/gvisor/runsc/profile"
"gvisor.dev/gvisor/runsc/sandbox"
"gvisor.dev/gvisor/runsc/specutils"
"gvisor.dev/gvisor/runsc/starttime"
)
const cgroupParentAnnotation = "dev.gvisor.spec.cgroup-parent"
// validateID validates the container id.
func validateID(id string) error {
// See libcontainer/factory_linux.go.
idRegex := regexp.MustCompile(`^[\w+\.-]+$`)
if !idRegex.MatchString(id) {
return fmt.Errorf("invalid container id: %v", id)
}
return nil
}
// Container represents a containerized application. When running, the
// container is associated with a single Sandbox.
//
// Container metadata can be saved and loaded to disk. Within a root directory,
// we maintain subdirectories for each container named with the container id.
// The container metadata is stored as a json within the container directory
// in a file named "meta.json". This metadata format is defined by us and is
// not part of the OCI spec.
//
// Containers must write their metadata files after any change to their internal
// states. The entire container directory is deleted when the container is
// destroyed.
//
// When the container is stopped, all processes that belong to the container
// must be stopped before Destroy() returns. containerd makes roughly the
// following calls to stop a container:
// - First it attempts to kill the container process with
// 'runsc kill SIGTERM'. After some time, it escalates to SIGKILL. In a
// separate thread, it's waiting on the container. As soon as the wait
// returns, it moves on to the next step:
// - It calls 'runsc kill --all SIGKILL' to stop every process that belongs to
// the container. 'kill --all SIGKILL' waits for all processes before
// returning.
// - Containerd waits for stdin, stdout and stderr to drain and be closed.
// - It calls 'runsc delete'. runc implementation kills --all SIGKILL once
// again just to be sure, waits, and then proceeds with remaining teardown.
//
// Container is thread-unsafe.
type Container struct {
// ID is the container ID.
ID string `json:"id"`
// Spec is the OCI runtime spec that configures this container.
Spec *specs.Spec `json:"spec"`
// BundleDir is the directory containing the container bundle.
BundleDir string `json:"bundleDir"`
// CreatedAt is the time the container was created.
CreatedAt time.Time `json:"createdAt"`
// Owner is the container owner.
Owner string `json:"owner"`
// ConsoleSocket is the path to a unix domain socket that will receive
// the console FD.
ConsoleSocket string `json:"consoleSocket"`
// Status is the current container Status.
Status Status `json:"status"`
// GoferPid is the PID of the gofer running along side the sandbox. May
// be 0 if the gofer has been killed.
GoferPid int `json:"goferPid"`
// Sandbox is the sandbox this container is running in. It's set when the
// container is created and reset when the sandbox is destroyed.
Sandbox *sandbox.Sandbox `json:"sandbox"`
// CompatCgroup has the cgroup configuration for the container. For the single
// container case, container cgroup is set in `c.Sandbox` only. CompactCgroup
// is only set for multi-container, where the `c.Sandbox` cgroup represents
// the entire pod.
//
// Note that CompatCgroup is created only for compatibility with tools
// that expect container cgroups to exist. Setting limits here makes no change
// to the container in question.
CompatCgroup cgroup.CgroupJSON `json:"compatCgroup"`
// Saver handles load from/save to the state file safely from multiple
// processes.
Saver StateFile `json:"saver"`
// GoferMountConfs contains information about how the gofer mounts have been
// overlaid (with tmpfs or overlayfs). The first entry is for rootfs and the
// following entries are for bind mounts in Spec.Mounts (in the same order).
GoferMountConfs boot.GoferMountConfFlags `json:"goferMountConfs"`
//
// Fields below this line are not saved in the state file and will not
// be preserved across commands.
//
// goferIsChild is set if a gofer process is a child of the current process.
//
// This field isn't saved to json, because only a creator of a gofer
// process will have it as a child process.
goferIsChild bool `nojson:"true"`
}
// Args is used to configure a new container.
type Args struct {
// ID is the container unique identifier.
ID string
// Spec is the OCI spec that describes the container.
Spec *specs.Spec
// BundleDir is the directory containing the container bundle.
BundleDir string
// ConsoleSocket is the path to a unix domain socket that will receive
// the console FD. It may be empty.
ConsoleSocket string
// PIDFile is the filename where the container's root process PID will be
// written to. It may be empty.
PIDFile string
// UserLog is the filename to send user-visible logs to. It may be empty.
//
// It only applies for the init container.
UserLog string
// Attached indicates that the sandbox lifecycle is attached with the caller.
// If the caller exits, the sandbox should exit too.
//
// It only applies for the init container.
Attached bool
// PassFiles are user-supplied files from the host to be exposed to the
// sandboxed app.
PassFiles map[int]*os.File
// ExecFile is the host file used for program execution.
ExecFile *os.File
}
// New creates the container in a new Sandbox process, unless the metadata
// indicates that an existing Sandbox should be used. The caller must call
// Destroy() on the container.
func New(conf *config.Config, args Args) (*Container, error) {
log.Debugf("Create container, cid: %s, rootDir: %q", args.ID, conf.RootDir)
if err := validateID(args.ID); err != nil {
return nil, err
}
if err := os.MkdirAll(conf.RootDir, 0711); err != nil {
return nil, fmt.Errorf("creating container root directory %q: %v", conf.RootDir, err)
}
if err := modifySpecForDirectfs(conf, args.Spec); err != nil {
return nil, fmt.Errorf("failed to modify spec for directfs: %v", err)
}
sandboxID := args.ID
if !isRoot(args.Spec) {
var ok bool
sandboxID, ok = specutils.SandboxID(args.Spec)
if !ok {
return nil, fmt.Errorf("no sandbox ID found when creating container")
}
}
c := &Container{
ID: args.ID,
Spec: args.Spec,
ConsoleSocket: args.ConsoleSocket,
BundleDir: args.BundleDir,
Status: Creating,
CreatedAt: time.Now(),
Owner: os.Getenv("USER"),
Saver: StateFile{
RootDir: conf.RootDir,
ID: FullID{
SandboxID: sandboxID,
ContainerID: args.ID,
},
},
}
// The Cleanup object cleans up partially created containers when an error
// occurs. Any errors occurring during cleanup itself are ignored.
cu := cleanup.Make(func() { _ = c.Destroy() })
defer cu.Clean()
// Lock the container metadata file to prevent concurrent creations of
// containers with the same id.
if err := c.Saver.LockForNew(); err != nil {
return nil, fmt.Errorf("cannot lock container metadata file: %w", err)
}
defer c.Saver.UnlockOrDie()
// If the metadata annotations indicate that this container should be started
// in an existing sandbox, we must do so. These are the possible metadata
// annotation states:
// 1. No annotations: it means that there is a single container and this
// container is obviously the root. Both container and sandbox share the
// ID.
// 2. Container type == sandbox: it means this is the root container
// starting the sandbox. Both container and sandbox share the same ID.
// 3. Container type == container: it means this is a subcontainer of an
// already started sandbox. In this case, container ID is different than
// the sandbox ID.
if isRoot(args.Spec) {
log.Debugf("Creating new sandbox for container, cid: %s", args.ID)
if args.Spec.Linux == nil {
args.Spec.Linux = &specs.Linux{}
}
// Don't force the use of cgroups in tests because they lack permission to do so.
if args.Spec.Linux.CgroupsPath == "" && !conf.TestOnlyAllowRunAsCurrentUserWithoutChroot {
args.Spec.Linux.CgroupsPath = "/" + args.ID
}
var subCgroup, parentCgroup, containerCgroup cgroup.Cgroup
if !conf.IgnoreCgroups {
var err error
// Create and join cgroup before processes are created to ensure they are
// part of the cgroup from the start (and all their children processes).
parentCgroup, subCgroup, err = c.setupCgroupForRoot(conf, args.Spec)
if err != nil {
return nil, fmt.Errorf("cannot set up cgroup for root: %w", err)
}
// Join the child cgroup when using cgroupfs. Joining non leaf-node
// cgroups is illegal in cgroupsv2 and will return EBUSY.
if subCgroup != nil && !conf.SystemdCgroup && cgroup.IsOnlyV2() {
containerCgroup = subCgroup
} else {
containerCgroup = parentCgroup
}
}
c.CompatCgroup = cgroup.CgroupJSON{Cgroup: subCgroup}
mountHints, err := boot.NewPodMountHints(args.Spec)
if err != nil {
return nil, fmt.Errorf("error creating pod mount hints: %w", err)
}
rootfsHint, err := boot.NewRootfsHint(args.Spec)
if err != nil {
return nil, fmt.Errorf("error creating rootfs hint: %w", err)
}
goferFilestores, goferConfs, err := c.createGoferFilestores(conf.GetOverlay2(), mountHints, rootfsHint)
if err != nil {
return nil, err
}
if !goferConfs[0].ShouldUseLisafs() && specutils.GPUFunctionalityRequestedViaHook(args.Spec, conf) {
// nvidia-container-runtime-hook attempts to populate the container
// rootfs with NVIDIA libraries and devices. With EROFS, spec.Root.Path
// points to an empty directory and populating that has no effect.
return nil, fmt.Errorf("nvidia-container-runtime-hook cannot be used together with non-lisafs backed root mount")
}
c.GoferMountConfs = goferConfs
if err := nvProxyPreGoferHostSetup(args.Spec, conf); err != nil {
return nil, err
}
if err := runInCgroup(containerCgroup, func() error {
ioFiles, devIOFile, specFile, err := c.createGoferProcess(args.Spec, conf, args.BundleDir, args.Attached, rootfsHint)
if err != nil {
return fmt.Errorf("cannot create gofer process: %w", err)
}
// Start a new sandbox for this container. Any errors after this point
// must destroy the container.
sandArgs := &sandbox.Args{
ID: sandboxID,
Spec: args.Spec,
BundleDir: args.BundleDir,
ConsoleSocket: args.ConsoleSocket,
UserLog: args.UserLog,
IOFiles: ioFiles,
DevIOFile: devIOFile,
MountsFile: specFile,
Cgroup: containerCgroup,
Attached: args.Attached,
GoferFilestoreFiles: goferFilestores,
GoferMountConfs: goferConfs,
MountHints: mountHints,
PassFiles: args.PassFiles,
ExecFile: args.ExecFile,
}
sand, err := sandbox.New(conf, sandArgs)
if err != nil {
return fmt.Errorf("cannot create sandbox: %w", err)
}
c.Sandbox = sand
return nil
}); err != nil {
return nil, err
}
} else {
log.Debugf("Creating new container, cid: %s, sandbox: %s", c.ID, sandboxID)
// Find the sandbox associated with this ID.
fullID := FullID{
SandboxID: sandboxID,
ContainerID: sandboxID,
}
sb, err := Load(conf.RootDir, fullID, LoadOpts{Exact: true})
if err != nil {
return nil, fmt.Errorf("cannot load sandbox: %w", err)
}
c.Sandbox = sb.Sandbox
subCgroup, err := c.setupCgroupForSubcontainer(conf, args.Spec)
if err != nil {
return nil, err
}
c.CompatCgroup = cgroup.CgroupJSON{Cgroup: subCgroup}
// If the console control socket file is provided, then create a new
// pty master/slave pair and send the TTY to the sandbox process.
var tty *os.File
if c.ConsoleSocket != "" {
// Create a new TTY pair and send the master on the provided socket.
var err error
tty, err = console.NewWithSocket(c.ConsoleSocket)
if err != nil {
return nil, fmt.Errorf("setting up console with socket %q: %w", c.ConsoleSocket, err)
}
// tty file is transferred to the sandbox, then it can be closed here.
defer tty.Close()
}
if err := c.Sandbox.CreateSubcontainer(conf, c.ID, tty); err != nil {
return nil, fmt.Errorf("cannot create subcontainer: %w", err)
}
}
c.changeStatus(Created)
// Save the metadata file.
if err := c.saveLocked(); err != nil {
return nil, err
}
// "If any prestart hook fails, the runtime MUST generate an error,
// stop and destroy the container" -OCI spec.
if c.Spec.Hooks != nil {
// Even though the hook name is Prestart, runc used to call it from create.
// For this reason, it's now deprecated, but the spec requires it to be
// called *before* CreateRuntime and CreateRuntime must be called in create.
//
// "For runtimes that implement the deprecated prestart hooks as
// createRuntime hooks, createRuntime hooks MUST be called after the
// prestart hooks."
if err := executeHooks(c.Spec.Hooks.Prestart, c.State()); err != nil {
return nil, err
}
if err := executeHooks(c.Spec.Hooks.CreateRuntime, c.State()); err != nil {
return nil, err
}
if len(c.Spec.Hooks.CreateContainer) > 0 {
log.Warningf("CreateContainer hook skipped because running inside container namespace is not supported")
}
}
// Write the PID file. Containerd considers the call to create complete after
// this file is created, so it must be the last thing we do.
if args.PIDFile != "" {
if err := ioutil.WriteFile(args.PIDFile, []byte(strconv.Itoa(c.SandboxPid())), 0644); err != nil {
return nil, fmt.Errorf("error writing PID file: %v", err)
}
}
cu.Release()
return c, nil
}
// Start starts running the containerized process inside the sandbox.
func (c *Container) Start(conf *config.Config) error {
log.Debugf("Start container, cid: %s", c.ID)
return c.startImpl(conf, "start", c.Sandbox.StartRoot, c.Sandbox.StartSubcontainer)
}
// Restore takes a container and replaces its kernel and file system
// to restore a container from its state file.
func (c *Container) Restore(conf *config.Config, imagePath string, direct bool) error {
log.Debugf("Restore container, cid: %s", c.ID)
restore := func(conf *config.Config) error {
return c.Sandbox.Restore(conf, c.ID, imagePath, direct)
}
return c.startImpl(conf, "restore", restore, c.Sandbox.RestoreSubcontainer)
}
func (c *Container) startImpl(conf *config.Config, action string, startRoot func(conf *config.Config) error, startSub func(spec *specs.Spec, conf *config.Config, cid string, stdios, goferFiles, goferFilestores []*os.File, devIOFile *os.File, goferConfs []boot.GoferMountConf) error) error {
if err := c.Saver.lock(BlockAcquire); err != nil {
return err
}
unlock := cleanup.Make(c.Saver.UnlockOrDie)
defer unlock.Clean()
if err := c.requireStatus(action, Created); err != nil {
return err
}
// "If any prestart hook fails, the runtime MUST generate an error,
// stop and destroy the container" -OCI spec.
if c.Spec.Hooks != nil && len(c.Spec.Hooks.StartContainer) > 0 {
log.Warningf("StartContainer hook skipped because running inside container namespace is not supported")
}
if isRoot(c.Spec) {
if err := startRoot(conf); err != nil {
return err
}
} else {
rootfsHint, err := boot.NewRootfsHint(c.Spec)
if err != nil {
return fmt.Errorf("error creating rootfs hint: %w", err)
}
goferFilestores, goferConfs, err := c.createGoferFilestores(conf.GetOverlay2(), c.Sandbox.MountHints, rootfsHint)
if err != nil {
return err
}
c.GoferMountConfs = goferConfs
// Join cgroup to start gofer process to ensure it's part of the cgroup from
// the start (and all their children processes).
if err := runInCgroup(c.Sandbox.CgroupJSON.Cgroup, func() error {
// Create the gofer process.
goferFiles, devIOFile, mountsFile, err := c.createGoferProcess(c.Spec, conf, c.BundleDir, false, rootfsHint)
if err != nil {
return err
}
defer func() {
if mountsFile != nil {
_ = mountsFile.Close()
}
if devIOFile != nil {
_ = devIOFile.Close()
}
for _, f := range goferFiles {
_ = f.Close()
}
for _, f := range goferFilestores {
_ = f.Close()
}
}()
if mountsFile != nil {
cleanMounts, err := specutils.ReadMounts(mountsFile)
if err != nil {
return fmt.Errorf("reading mounts file: %v", err)
}
c.Spec.Mounts = cleanMounts
}
// Setup stdios if the container is not using terminal. Otherwise TTY was
// already setup in create.
var stdios []*os.File
if !c.Spec.Process.Terminal {
stdios = []*os.File{os.Stdin, os.Stdout, os.Stderr}
}
return startSub(c.Spec, conf, c.ID, stdios, goferFiles, goferFilestores, devIOFile, goferConfs)
}); err != nil {
return err
}
}
// "If any poststart hook fails, the runtime MUST log a warning, but
// the remaining hooks and lifecycle continue as if the hook had
// succeeded" -OCI spec.
if c.Spec.Hooks != nil {
executeHooksBestEffort(c.Spec.Hooks.Poststart, c.State())
}
c.changeStatus(Running)
if err := c.saveLocked(); err != nil {
return err
}
// Release lock before adjusting OOM score because the lock is acquired there.
unlock.Clean()
// Adjust the oom_score_adj for sandbox. This must be done after saveLocked().
if err := adjustSandboxOOMScoreAdj(c.Sandbox, c.Spec, c.Saver.RootDir, false); err != nil {
return err
}
// Set container's oom_score_adj to the gofer since it is dedicated to
// the container, in case the gofer uses up too much memory.
return c.adjustGoferOOMScoreAdj()
}
// Run is a helper that calls Create + Start + Wait.
func Run(conf *config.Config, args Args) (unix.WaitStatus, error) {
log.Debugf("Run container, cid: %s, rootDir: %q", args.ID, conf.RootDir)
c, err := New(conf, args)
if err != nil {
return 0, fmt.Errorf("creating container: %v", err)
}
// Clean up partially created container if an error occurs.
// Any errors returned by Destroy() itself are ignored.
cu := cleanup.Make(func() {
c.Destroy()
})
defer cu.Clean()
if err := c.Start(conf); err != nil {
return 0, fmt.Errorf("starting container: %v", err)
}
// If we allocate a terminal, forward signals to the sandbox process.
// Otherwise, Ctrl+C will terminate this process and its children,
// including the terminal.
if c.Spec.Process.Terminal {
stopForwarding := c.ForwardSignals(0, true /* fgProcess */)
defer stopForwarding()
}
if args.Attached {
return c.Wait()
}
cu.Release()
return 0, nil
}
// Execute runs the specified command in the container. It returns the PID of
// the newly created process.
func (c *Container) Execute(conf *config.Config, args *control.ExecArgs) (int32, error) {
log.Debugf("Execute in container, cid: %s, args: %+v", c.ID, args)
if err := c.requireStatus("execute in", Created, Running); err != nil {
return 0, err
}
args.ContainerID = c.ID
return c.Sandbox.Execute(conf, args)
}
// Event returns events for the container.
func (c *Container) Event() (*boot.EventOut, error) {
log.Debugf("Getting events for container, cid: %s", c.ID)
if err := c.requireStatus("get events for", Created, Running, Paused); err != nil {
return nil, err
}
event, err := c.Sandbox.Event(c.ID)
if err != nil {
return nil, err
}
if len(event.ContainerUsage) > 0 {
// Some stats can utilize host cgroups for accuracy.
c.populateStats(event)
}
return event, nil
}
// PortForward starts port forwarding to the container.
func (c *Container) PortForward(opts *boot.PortForwardOpts) error {
if err := c.requireStatus("port forward", Running); err != nil {
return err
}
opts.ContainerID = c.ID
return c.Sandbox.PortForward(opts)
}
// SandboxPid returns the Getpid of the sandbox the container is running in, or -1 if the
// container is not running.
func (c *Container) SandboxPid() int {
if err := c.requireStatus("get PID", Created, Running, Paused); err != nil {
return -1
}
return c.Sandbox.Getpid()
}
// Wait waits for the container to exit, and returns its WaitStatus.
// Call to wait on a stopped container is needed to retrieve the exit status
// and wait returns immediately.
func (c *Container) Wait() (unix.WaitStatus, error) {
log.Debugf("Wait on container, cid: %s", c.ID)
ws, err := c.Sandbox.Wait(c.ID)
if err == nil {
// Wait succeeded, container is not running anymore.
c.changeStatus(Stopped)
}
return ws, err
}
// WaitRootPID waits for process 'pid' in the sandbox's PID namespace and
// returns its WaitStatus.
func (c *Container) WaitRootPID(pid int32) (unix.WaitStatus, error) {
log.Debugf("Wait on process %d in sandbox, cid: %s", pid, c.Sandbox.ID)
if !c.IsSandboxRunning() {
return 0, fmt.Errorf("sandbox is not running")
}
return c.Sandbox.WaitPID(c.Sandbox.ID, pid)
}
// WaitPID waits for process 'pid' in the container's PID namespace and returns
// its WaitStatus.
func (c *Container) WaitPID(pid int32) (unix.WaitStatus, error) {
log.Debugf("Wait on process %d in container, cid: %s", pid, c.ID)
if !c.IsSandboxRunning() {
return 0, fmt.Errorf("sandbox is not running")
}
return c.Sandbox.WaitPID(c.ID, pid)
}
// WaitCheckpoint waits for the Kernel to have been successfully checkpointed
// n-1 times, then waits for either the n-th successful checkpoint (in which
// case it returns nil) or any number of failed checkpoints (in which case it
// returns an error returned by any such failure).
func (c *Container) WaitCheckpoint(n uint32) error {
log.Debugf("Wait on %d-th checkpoint to complete in container, cid: %s", n, c.ID)
if !c.IsSandboxRunning() {
return fmt.Errorf("sandbox is not running")
}
return c.Sandbox.WaitCheckpoint(n)
}
// SignalContainer sends the signal to the container. If all is true and signal
// is SIGKILL, then waits for all processes to exit before returning.
// SignalContainer returns an error if the container is already stopped.
// TODO(b/113680494): Distinguish different error types.
func (c *Container) SignalContainer(sig unix.Signal, all bool) error {
log.Debugf("Signal container, cid: %s, signal: %v (%d)", c.ID, sig, sig)
// Signaling container in Stopped state is allowed. When all=false,
// an error will be returned anyway; when all=true, this allows
// sending signal to other processes inside the container even
// after the init process exits. This is especially useful for
// container cleanup.
if err := c.requireStatus("signal", Running, Stopped); err != nil {
return err
}
if !c.IsSandboxRunning() {
return fmt.Errorf("sandbox is not running")
}
return c.Sandbox.SignalContainer(c.ID, sig, all)
}
// SignalProcess sends sig to a specific process in the container.
func (c *Container) SignalProcess(sig unix.Signal, pid int32) error {
log.Debugf("Signal process %d in container, cid: %s, signal: %v (%d)", pid, c.ID, sig, sig)
if err := c.requireStatus("signal a process inside", Running); err != nil {
return err
}
if !c.IsSandboxRunning() {
return fmt.Errorf("sandbox is not running")
}
return c.Sandbox.SignalProcess(c.ID, int32(pid), sig, false)
}
// ForwardSignals forwards all signals received by the current process to the
// container process inside the sandbox. It returns a function that will stop
// forwarding signals.
func (c *Container) ForwardSignals(pid int32, fgProcess bool) func() {
log.Debugf("Forwarding all signals to container, cid: %s, PIDPID: %d, fgProcess: %t", c.ID, pid, fgProcess)
stop := sighandling.StartSignalForwarding(func(sig linux.Signal) {
log.Debugf("Forwarding signal %d to container, cid: %s, PID: %d, fgProcess: %t", sig, c.ID, pid, fgProcess)
if err := c.Sandbox.SignalProcess(c.ID, pid, unix.Signal(sig), fgProcess); err != nil {
log.Warningf("error forwarding signal %d to container %q: %v", sig, c.ID, err)
}
})
return func() {
log.Debugf("Done forwarding signals to container, cid: %s, PID: %d, fgProcess: %t", c.ID, pid, fgProcess)
stop()
}
}
// Checkpoint sends the checkpoint call to the container.
// The statefile will be written to f, the file at the specified image-path.
func (c *Container) Checkpoint(imagePath string, direct bool, sfOpts statefile.Options, mfOpts pgalloc.SaveOpts) error {
log.Debugf("Checkpoint container, cid: %s", c.ID)
if err := c.requireStatus("checkpoint", Created, Running, Paused); err != nil {
return err
}
return c.Sandbox.Checkpoint(c.ID, imagePath, direct, sfOpts, mfOpts)
}
// Pause suspends the container and its kernel.
// The call only succeeds if the container's status is created or running.
func (c *Container) Pause() error {
log.Debugf("Pausing container, cid: %s", c.ID)
if err := c.Saver.lock(BlockAcquire); err != nil {
return err
}
defer c.Saver.UnlockOrDie()
if c.Status != Created && c.Status != Running {
return fmt.Errorf("cannot pause container %q in state %v", c.ID, c.Status)
}
if err := c.Sandbox.Pause(c.ID); err != nil {
return fmt.Errorf("pausing container %q: %v", c.ID, err)
}
c.changeStatus(Paused)
return c.saveLocked()
}
// Resume unpauses the container and its kernel.
// The call only succeeds if the container's status is paused.
func (c *Container) Resume() error {
log.Debugf("Resuming container, cid: %s", c.ID)
if err := c.Saver.lock(BlockAcquire); err != nil {
return err
}
defer c.Saver.UnlockOrDie()
if c.Status != Paused {
return fmt.Errorf("cannot resume container %q in state %v", c.ID, c.Status)
}
if err := c.Sandbox.Resume(c.ID); err != nil {
return fmt.Errorf("resuming container: %v", err)
}
c.changeStatus(Running)
return c.saveLocked()
}
// State returns the metadata of the container.
func (c *Container) State() specs.State {
return specs.State{
Version: specs.Version,
ID: c.ID,
Status: c.Status,
Pid: c.SandboxPid(),
Bundle: c.BundleDir,
Annotations: c.Spec.Annotations,
}
}
// Processes retrieves the list of processes and associated metadata inside a
// container.
func (c *Container) Processes() ([]*control.Process, error) {
if err := c.requireStatus("get processes of", Running, Paused); err != nil {
return nil, err
}
return c.Sandbox.Processes(c.ID)
}
// Destroy stops all processes and frees all resources associated with the
// container.
func (c *Container) Destroy() error {
log.Debugf("Destroy container, cid: %s", c.ID)
if err := c.Saver.lock(BlockAcquire); err != nil {
return err
}
defer func() {
c.Saver.UnlockOrDie()
_ = c.Saver.close()
}()
// Stored for later use as stop() sets c.Sandbox to nil.
sb := c.Sandbox
// We must perform the following cleanup steps:
// * stop the container and gofer processes,
// * remove the container filesystem on the host, and
// * delete the container metadata directory.
//
// It's possible for one or more of these steps to fail, but we should
// do our best to perform all of the cleanups. Hence, we keep a slice
// of errors return their concatenation.
var errs []string
if err := c.stop(); err != nil {
err = fmt.Errorf("stopping container: %v", err)
log.Warningf("%v", err)
errs = append(errs, err.Error())
}
if err := c.Saver.Destroy(); err != nil {
err = fmt.Errorf("deleting container state files: %v", err)
log.Warningf("%v", err)
errs = append(errs, err.Error())
}
// Clean up self-backed filestore files created in their respective mounts.
c.forEachSelfMount(func(mountSrc string) {
if sb != nil {
if hint := sb.MountHints.FindMount(mountSrc); hint != nil && hint.ShouldShareMount() {
// Don't delete filestore file for shared mounts. The sandbox owns a
// shared master mount which uses this filestore and is shared with
// multiple mount points.
return
}
}
filestorePath := boot.SelfFilestorePath(mountSrc, c.sandboxID())
if err := os.Remove(filestorePath); err != nil {
err = fmt.Errorf("failed to delete filestore file %q: %v", filestorePath, err)
log.Warningf("%v", err)
errs = append(errs, err.Error())
}
})
if sb != nil && sb.IsRootContainer(c.ID) {
// When the root container is being destroyed, we can clean up filestores
// used by shared mounts.
for _, hint := range sb.MountHints.Mounts {
if !hint.ShouldShareMount() {
continue
}
// Assume this is a self-backed shared mount and try to delete the
// filestore. Subsequently ignore the ENOENT if the assumption is wrong.
filestorePath := boot.SelfFilestorePath(hint.Mount.Source, c.sandboxID())
if err := os.Remove(filestorePath); err != nil && !os.IsNotExist(err) {
err = fmt.Errorf("failed to delete shared filestore file %q: %v", filestorePath, err)
log.Warningf("%v", err)
errs = append(errs, err.Error())
}
}
}
c.changeStatus(Stopped)
// Adjust oom_score_adj for the sandbox. This must be done after the container
// is stopped and the directory at c.Root is removed.
//
// Use 'sb' to tell whether it has been executed before because Destroy must
// be idempotent.
if sb != nil {
if err := adjustSandboxOOMScoreAdj(sb, c.Spec, c.Saver.RootDir, true); err != nil {
errs = append(errs, err.Error())
}
}
// "If any poststop hook fails, the runtime MUST log a warning, but the
// remaining hooks and lifecycle continue as if the hook had
// succeeded" - OCI spec.
//
// Based on the OCI, "The post-stop hooks MUST be called after the container
// is deleted but before the delete operation returns"
// Run it here to:
// 1) Conform to the OCI.
// 2) Make sure it only runs once, because the root has been deleted, the
// container can't be loaded again.
if c.Spec.Hooks != nil {
executeHooksBestEffort(c.Spec.Hooks.Poststop, c.State())
}
if len(errs) == 0 {
return nil
}
return fmt.Errorf(strings.Join(errs, "\n"))
}
func (c *Container) sandboxID() string {
return c.Saver.ID.SandboxID
}
func (c *Container) forEachSelfMount(fn func(mountSrc string)) {
if c.GoferMountConfs == nil {
// Container not started? Skip.
return
}
if c.GoferMountConfs[0].IsSelfBacked() {
fn(c.Spec.Root.Path)
}
goferMntIdx := 1 // First index is for rootfs.
for i := range c.Spec.Mounts {
if !specutils.IsGoferMount(c.Spec.Mounts[i]) {
continue
}
if c.GoferMountConfs[goferMntIdx].IsSelfBacked() {
fn(c.Spec.Mounts[i].Source)
}
goferMntIdx++
}
}
// createGoferFilestores creates the regular files that will back the
// tmpfs/overlayfs mounts that will overlay some gofer mounts. It also returns
// information about how each gofer mount is configured.
func (c *Container) createGoferFilestores(ovlConf config.Overlay2, mountHints *boot.PodMountHints, rootfsHint *boot.RootfsHint) ([]*os.File, []boot.GoferMountConf, error) {
var goferFilestores []*os.File
var goferConfs []boot.GoferMountConf
// Handle root mount first.
overlayMedium := ovlConf.RootOverlayMedium()
mountType := boot.Bind
if rootfsHint != nil {
overlayMedium = rootfsHint.Overlay
if !specutils.IsGoferMount(rootfsHint.Mount) {
mountType = rootfsHint.Mount.Type
}
}
if c.Spec.Root.Readonly {
overlayMedium = config.NoOverlay
}
filestore, goferConf, err := c.createGoferFilestore(overlayMedium, c.Spec.Root.Path, mountType, false /* isShared */)
if err != nil {
return nil, nil, err
}
if filestore != nil {
goferFilestores = append(goferFilestores, filestore)
}
goferConfs = append(goferConfs, goferConf)
// Handle bind mounts.
for i := range c.Spec.Mounts {
if !specutils.IsGoferMount(c.Spec.Mounts[i]) {
continue
}
overlayMedium = ovlConf.SubMountOverlayMedium()
mountType = boot.Bind
isShared := false
if specutils.IsReadonlyMount(c.Spec.Mounts[i].Options) {
overlayMedium = config.NoOverlay
}
if hint := mountHints.FindMount(c.Spec.Mounts[i].Source); hint != nil {
// Note that we want overlayMedium=self even if this is a read-only mount so that
// the shared mount is created correctly. Future containers may mount this writably.
overlayMedium = config.SelfOverlay
if !specutils.IsGoferMount(hint.Mount) {
mountType = hint.Mount.Type
}
isShared = hint.ShouldShareMount()
}
filestore, goferConf, err := c.createGoferFilestore(overlayMedium, c.Spec.Mounts[i].Source, mountType, isShared)
if err != nil {
return nil, nil, err
}
if filestore != nil {
goferFilestores = append(goferFilestores, filestore)
}
goferConfs = append(goferConfs, goferConf)
}
for _, filestore := range goferFilestores {
// Perform this work around outside the sandbox. The sandbox may already be
// running with seccomp filters that do not allow this.
pgalloc.IMAWorkAroundForMemFile(filestore.Fd())
}
return goferFilestores, goferConfs, nil
}
func (c *Container) createGoferFilestore(overlayMedium config.OverlayMedium, mountSrc string, mountType string, isShared bool) (*os.File, boot.GoferMountConf, error) {
var lower boot.GoferMountConfLowerType
switch mountType {
case boot.Bind:
lower = boot.Lisafs
case tmpfs.Name:
lower = boot.NoneLower
case erofs.Name:
lower = boot.Erofs
default:
return nil, boot.GoferMountConf{}, fmt.Errorf("unsupported mount type %q in mount hint", mountType)
}
switch overlayMedium {
case config.NoOverlay:
return nil, boot.GoferMountConf{Lower: lower, Upper: boot.NoOverlay}, nil
case config.MemoryOverlay:
return nil, boot.GoferMountConf{Lower: lower, Upper: boot.MemoryOverlay}, nil
case config.SelfOverlay:
return c.createGoferFilestoreInSelf(mountSrc, isShared, boot.GoferMountConf{Lower: lower, Upper: boot.SelfOverlay})
default:
if overlayMedium.IsBackedByAnon() {
return c.createGoferFilestoreInDir(overlayMedium.HostFileDir(), boot.GoferMountConf{Lower: lower, Upper: boot.AnonOverlay})
}
return nil, boot.GoferMountConf{}, fmt.Errorf("unexpected overlay medium %q", overlayMedium)
}
}
func (c *Container) createGoferFilestoreInSelf(mountSrc string, isShared bool, successConf boot.GoferMountConf) (*os.File, boot.GoferMountConf, error) {
mountSrcInfo, err := os.Stat(mountSrc)
if err != nil {
return nil, boot.GoferMountConf{}, fmt.Errorf("failed to stat mount %q to see if it were a directory: %v", mountSrc, err)
}
if !mountSrcInfo.IsDir() {
log.Warningf("self filestore is only supported for directory mounts, but mount %q is not a directory, falling back to memory", mountSrc)
return nil, boot.GoferMountConf{Lower: successConf.Lower, Upper: boot.MemoryOverlay}, nil
}
// Create the self filestore file.
createFlags := unix.O_RDWR | unix.O_CREAT | unix.O_CLOEXEC
if !isShared {
// Allow shared mounts to reuse existing filestore. A previous shared user
// may have already set up the filestore.
createFlags |= unix.O_EXCL
}
filestorePath := boot.SelfFilestorePath(mountSrc, c.sandboxID())
filestoreFD, err := unix.Open(filestorePath, createFlags, 0666)
if err != nil {
if err == unix.EEXIST {
// Note that if the same submount is mounted multiple times within the
// same sandbox, and is not shared, then the overlay option doesn't work
// correctly. Because each overlay mount is independent and changes to
// one are not visible to the other.
return nil, boot.GoferMountConf{}, fmt.Errorf("%q mount source already has a filestore file at %q; repeated submounts are not supported with overlay optimizations", mountSrc, filestorePath)
}
return nil, boot.GoferMountConf{}, fmt.Errorf("failed to create filestore file inside %q: %v", mountSrc, err)
}
log.Debugf("Created filestore file at %q for mount source %q", filestorePath, mountSrc)
// Filestore in self should be a named path because it needs to be
// discoverable via path traversal so that k8s can scan the filesystem
// and apply any limits appropriately (like local ephemeral storage
// limits). So don't delete it. These files will be unlinked when the
// container is destroyed. This makes self medium appropriate for k8s.
return os.NewFile(uintptr(filestoreFD), filestorePath), successConf, nil
}
func (c *Container) createGoferFilestoreInDir(filestoreDir string, successConf boot.GoferMountConf) (*os.File, boot.GoferMountConf, error) {
fileInfo, err := os.Stat(filestoreDir)
if err != nil {
return nil, boot.GoferMountConf{}, fmt.Errorf("failed to stat filestore directory %q: %v", filestoreDir, err)
}
if !fileInfo.IsDir() {
return nil, boot.GoferMountConf{}, fmt.Errorf("overlay2 flag should specify an existing directory")
}
// Create an unnamed temporary file in filestore directory which will be
// deleted when the last FD on it is closed. We don't use O_TMPFILE because
// it is not supported on all filesystems. So we simulate it by creating a
// named file and then immediately unlinking it while keeping an FD on it.
// This file will be deleted when the container exits.
filestoreFile, err := os.CreateTemp(filestoreDir, "runsc-filestore-")
if err != nil {
return nil, boot.GoferMountConf{}, fmt.Errorf("failed to create a temporary file inside %q: %v", filestoreDir, err)
}
if err := unix.Unlink(filestoreFile.Name()); err != nil {
return nil, boot.GoferMountConf{}, fmt.Errorf("failed to unlink temporary file %q: %v", filestoreFile.Name(), err)
}
log.Debugf("Created an unnamed filestore file at %q", filestoreDir)
return filestoreFile, successConf, nil
}
// saveLocked saves the container metadata to a file.
//
// Precondition: container must be locked with container.lock().
func (c *Container) saveLocked() error {
log.Debugf("Save container, cid: %s", c.ID)
if err := c.Saver.SaveLocked(c); err != nil {
return fmt.Errorf("saving container metadata: %v", err)
}
return nil
}
// stop stops the container (for regular containers) or the sandbox (for
// root containers), and waits for the container or sandbox and the gofer
// to stop. If any of them doesn't stop before timeout, an error is returned.
func (c *Container) stop() error {
var parentCgroup cgroup.Cgroup
if c.Sandbox != nil {
log.Debugf("Destroying container, cid: %s", c.ID)
if err := c.Sandbox.DestroyContainer(c.ID); err != nil {
return fmt.Errorf("destroying container %q: %v", c.ID, err)
}
// Only uninstall parentCgroup for sandbox stop.
if c.Sandbox.IsRootContainer(c.ID) {
parentCgroup = c.Sandbox.CgroupJSON.Cgroup
}
// Only set sandbox to nil after it has been told to destroy the container.
c.Sandbox = nil
}
// Try killing gofer if it does not exit with container.
if c.GoferPid != 0 {
log.Debugf("Killing gofer for container, cid: %s, PID: %d", c.ID, c.GoferPid)
if err := unix.Kill(c.GoferPid, unix.SIGKILL); err != nil {
// The gofer may already be stopped, log the error.
log.Warningf("Error sending signal %d to gofer %d: %v", unix.SIGKILL, c.GoferPid, err)
}
}
if err := c.waitForStopped(); err != nil {
return err
}
// Delete container cgroup if any.
if c.CompatCgroup.Cgroup != nil {
if err := c.CompatCgroup.Cgroup.Uninstall(); err != nil {
return err
}
}
// Gofer is running inside parentCgroup, so Cgroup.Uninstall has to be called
// after the gofer has stopped.
if parentCgroup != nil {
if err := parentCgroup.Uninstall(); err != nil {
return err
}
}
return nil
}
func (c *Container) waitForStopped() error {
if c.GoferPid == 0 {
return nil
}
if c.IsSandboxRunning() {
if err := c.SignalContainer(unix.Signal(0), false); err == nil {
return fmt.Errorf("container is still running")
}
}
if c.goferIsChild {
// The gofer process is a child of the current process,
// so we can wait it and collect its zombie.
if _, err := unix.Wait4(int(c.GoferPid), nil, 0, nil); err != nil {
return fmt.Errorf("error waiting the gofer process: %v", err)
}
c.GoferPid = 0
return nil
}
ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()
b := backoff.WithContext(backoff.NewConstantBackOff(100*time.Millisecond), ctx)
op := func() error {
if err := unix.Kill(c.GoferPid, 0); err == nil {
return fmt.Errorf("gofer is still running")
}
c.GoferPid = 0
return nil
}
return backoff.Retry(op, b)
}
// shouldCreateDeviceGofer indicates whether a device gofer connection should
// be created.
func shouldCreateDeviceGofer(spec *specs.Spec, conf *config.Config) bool {
return specutils.GPUFunctionalityRequested(spec, conf) || specutils.TPUFunctionalityRequested(spec, conf)
}
// shouldSpawnGofer indicates whether the gofer process should be spawned.
func shouldSpawnGofer(spec *specs.Spec, conf *config.Config, goferConfs []boot.GoferMountConf) bool {
// Lisafs mounts need the gofer.
for _, cfg := range goferConfs {
if cfg.ShouldUseLisafs() {
return true
}
}
// Device gofer needs a gofer process.
return shouldCreateDeviceGofer(spec, conf)
}
// createGoferProcess returns an IO file list and a mounts file on success.
// The IO file list consists of image files and/or socket files to connect to
// a gofer endpoint for the mount points using Gofers. The mounts file is the
// file to read list of mounts after they have been resolved (direct paths,
// no symlinks), and will be nil if there is no cleaning required for mounts.
func (c *Container) createGoferProcess(spec *specs.Spec, conf *config.Config, bundleDir string, attached bool, rootfsHint *boot.RootfsHint) ([]*os.File, *os.File, *os.File, error) {
if !shouldSpawnGofer(spec, conf, c.GoferMountConfs) {
if !c.GoferMountConfs[0].ShouldUseErofs() {
panic("goferless mode is only possible with EROFS rootfs")
}
ioFile, err := os.Open(rootfsHint.Mount.Source)
if err != nil {
return nil, nil, nil, fmt.Errorf("opening rootfs image %q: %v", rootfsHint.Mount.Source, err)
}
return []*os.File{ioFile}, nil, nil, nil
}
// Ensure we don't leak FDs to the gofer process.
if err := sandbox.SetCloExeOnAllFDs(); err != nil {
return nil, nil, nil, fmt.Errorf("setting CLOEXEC on all FDs: %w", err)
}
donations := donation.Agency{}
defer donations.Close()
if err := donations.OpenAndDonate("log-fd", conf.LogFilename, os.O_CREATE|os.O_WRONLY|os.O_APPEND); err != nil {
return nil, nil, nil, err
}
if conf.DebugLog != "" {
test := ""
if len(conf.TestOnlyTestNameEnv) != 0 {
// Fetch test name if one is provided and the test only flag was set.
if t, ok := specutils.EnvVar(spec.Process.Env, conf.TestOnlyTestNameEnv); ok {
test = t
}
}
if specutils.IsDebugCommand(conf, "gofer") {
// The startTime here can mean one of two things:
// - If this is the first gofer started at the same time as the sandbox,
// then this starttime will exactly match the one used by the sandbox
// itself (i.e. `Sandbox.StartTime`). This is desirable, such that the
// first gofer's log filename will have the exact same timestamp as
// the sandbox's log filename timestamp.
// - If this is not the first gofer, then this starttime will be later
// than the sandbox start time; this is desirable such that we can
// distinguish the gofer log filenames between each other.
// In either case, `starttime.Get` gets us the timestamp we want.
startTime := starttime.Get()
if err := donations.DonateDebugLogFile("debug-log-fd", conf.DebugLog, "gofer", test, startTime); err != nil {
return nil, nil, nil, err
}
}
}
// Start with the general config flags.
cmd := exec.Command(specutils.ExePath, conf.ToFlags()...)
cmd.SysProcAttr = &unix.SysProcAttr{
// Detach from session. Otherwise, signals sent to the foreground process
// will also be forwarded by this process, resulting in duplicate signals.
Setsid: true,
}
// Set Args[0] to make easier to spot the gofer process. Otherwise it's
// shown as `exe`.
cmd.Args[0] = "runsc-gofer"
// Tranfer FDs that need to be present before the "gofer" command.
// Start at 3 because 0, 1, and 2 are taken by stdin/out/err.
nextFD := donations.Transfer(cmd, 3)
cmd.Args = append(cmd.Args, "gofer", "--bundle", bundleDir)
cmd.Args = append(cmd.Args, "--gofer-mount-confs="+c.GoferMountConfs.String())
// Open the spec file to donate to the sandbox.
specFile, err := specutils.OpenSpec(bundleDir)
if err != nil {
return nil, nil, nil, fmt.Errorf("opening spec file: %v", err)
}
donations.DonateAndClose("spec-fd", specFile)
// Donate any profile FDs to the gofer.
if err := c.donateGoferProfileFDs(conf, &donations); err != nil {
return nil, nil, nil, fmt.Errorf("donating gofer profile fds: %w", err)
}
// Create pipe that allows gofer to send mount list to sandbox after all paths
// have been resolved.
mountsSand, mountsGofer, err := os.Pipe()
if err != nil {
return nil, nil, nil, err
}
donations.DonateAndClose("mounts-fd", mountsGofer)
// Count the number of mounts that needs an IO file.
ioFileCount := 0
for _, cfg := range c.GoferMountConfs {
if cfg.ShouldUseLisafs() || cfg.ShouldUseErofs() {
ioFileCount++
}
}
sandEnds := make([]*os.File, 0, ioFileCount)
for i, cfg := range c.GoferMountConfs {
switch {
case cfg.ShouldUseLisafs():
fds, err := unix.Socketpair(unix.AF_UNIX, unix.SOCK_STREAM|unix.SOCK_CLOEXEC, 0)
if err != nil {
return nil, nil, nil, err
}
sandEnds = append(sandEnds, os.NewFile(uintptr(fds[0]), "sandbox IO FD"))
goferEnd := os.NewFile(uintptr(fds[1]), "gofer IO FD")
donations.DonateAndClose("io-fds", goferEnd)
case cfg.ShouldUseErofs():
if i > 0 {
return nil, nil, nil, fmt.Errorf("EROFS lower layer is only supported for root mount")
}
f, err := os.Open(rootfsHint.Mount.Source)
if err != nil {
return nil, nil, nil, fmt.Errorf("opening rootfs image %q: %v", rootfsHint.Mount.Source, err)
}
sandEnds = append(sandEnds, f)
}
}
var devSandEnd *os.File
if shouldCreateDeviceGofer(spec, conf) {
fds, err := unix.Socketpair(unix.AF_UNIX, unix.SOCK_STREAM|unix.SOCK_CLOEXEC, 0)
if err != nil {
return nil, nil, nil, err
}
devSandEnd = os.NewFile(uintptr(fds[0]), "sandbox dev IO FD")
donations.DonateAndClose("dev-io-fd", os.NewFile(uintptr(fds[1]), "gofer dev IO FD"))
}
if attached {
// The gofer is attached to the lifetime of this process, so it
// should synchronously die when this process dies.
cmd.SysProcAttr.Pdeathsig = unix.SIGKILL
}
// Enter new namespaces to isolate from the rest of the system. Don't unshare
// cgroup because gofer is added to a cgroup in the caller's namespace.
nss := []specs.LinuxNamespace{
{Type: specs.IPCNamespace},
{Type: specs.MountNamespace},
{Type: specs.NetworkNamespace},
{Type: specs.PIDNamespace},
{Type: specs.UTSNamespace},
}
rootlessEUID := unix.Geteuid() != 0
// Setup any uid/gid mappings, and create or join the configured user
// namespace so the gofer's view of the filesystem aligns with the
// users in the sandbox.
if !rootlessEUID {
if userNS, ok := specutils.GetNS(specs.UserNamespace, spec); ok {
nss = append(nss, userNS)
specutils.SetUIDGIDMappings(cmd, spec)
// We need to set UID and GID to have capabilities in a new user namespace.
cmd.SysProcAttr.Credential = &syscall.Credential{Uid: 0, Gid: 0}
}
} else {
userNS, ok := specutils.GetNS(specs.UserNamespace, spec)
if !ok {
return nil, nil, nil, fmt.Errorf("unable to run a rootless container without userns")
}
nss = append(nss, userNS)
syncFile, err := sandbox.ConfigureCmdForRootless(cmd, &donations)
if err != nil {
return nil, nil, nil, err
}
defer syncFile.Close()
}
nvProxySetup, err := nvproxySetupAfterGoferUserns(spec, conf, cmd, &donations)
if err != nil {
return nil, nil, nil, fmt.Errorf("setting up nvproxy for gofer: %w", err)
}
donations.Transfer(cmd, nextFD)
// Start the gofer in the given namespace.
donation.LogDonations(cmd)
log.Debugf("Starting gofer: %s %v", cmd.Path, cmd.Args)
if err := specutils.StartInNS(cmd, nss); err != nil {
return nil, nil, nil, fmt.Errorf("gofer: %v", err)
}
log.Infof("Gofer started, PID: %d", cmd.Process.Pid)
c.GoferPid = cmd.Process.Pid
c.goferIsChild = true
// Set up and synchronize rootless mode userns mappings.
if rootlessEUID {
if err := sandbox.SetUserMappings(spec, cmd.Process.Pid); err != nil {
return nil, nil, nil, err
}
}
// Set up nvproxy within the Gofer namespace.
if err := nvProxySetup(); err != nil {
return nil, nil, nil, fmt.Errorf("nvproxy setup: %w", err)
}
return sandEnds, devSandEnd, mountsSand, nil
}
// changeStatus transitions from one status to another ensuring that the
// transition is valid.
func (c *Container) changeStatus(s Status) {
switch s {
case Creating:
// Initial state, never transitions to it.
panic(fmt.Sprintf("invalid state transition: %v => %v", c.Status, s))
case Created:
if c.Status != Creating {
panic(fmt.Sprintf("invalid state transition: %v => %v", c.Status, s))
}
if c.Sandbox == nil {
panic("sandbox cannot be nil")
}
case Paused:
if c.Status != Running {
panic(fmt.Sprintf("invalid state transition: %v => %v", c.Status, s))
}
if c.Sandbox == nil {
panic("sandbox cannot be nil")
}
case Running:
if c.Status != Created && c.Status != Paused {
panic(fmt.Sprintf("invalid state transition: %v => %v", c.Status, s))
}
if c.Sandbox == nil {
panic("sandbox cannot be nil")
}
case Stopped:
// All states can transition to Stopped.
default:
panic(fmt.Sprintf("invalid new state: %v", s))
}
c.Status = s
}
// IsSandboxRunning returns true if the sandbox exists and is running.
func (c *Container) IsSandboxRunning() bool {
return c.Sandbox != nil && c.Sandbox.IsRunning()
}
// HasCapabilityInAnySet returns true if the given capability is in any of the
// capability sets of the container process.
func (c *Container) HasCapabilityInAnySet(capability linux.Capability) bool {
capString := capability.String()
for _, set := range [5][]string{
c.Spec.Process.Capabilities.Bounding,
c.Spec.Process.Capabilities.Effective,
c.Spec.Process.Capabilities.Inheritable,
c.Spec.Process.Capabilities.Permitted,
c.Spec.Process.Capabilities.Ambient,
} {
for _, c := range set {
if c == capString {
return true
}
}
}
return false
}
// RunsAsUID0 returns true if the container process runs with UID 0 (root).
func (c *Container) RunsAsUID0() bool {
return c.Spec.Process.User.UID == 0
}
func (c *Container) requireStatus(action string, statuses ...Status) error {
for _, s := range statuses {
if c.Status == s {
return nil
}
}
return fmt.Errorf("cannot %s container %q in state %s", action, c.ID, c.Status)
}
// IsSandboxRoot returns true if this container is its sandbox's root container.
func (c *Container) IsSandboxRoot() bool {
return isRoot(c.Spec)
}
func isRoot(spec *specs.Spec) bool {
return specutils.SpecContainerType(spec) != specutils.ContainerTypeContainer
}
// runInCgroup executes fn inside the specified cgroup. If cg is nil, execute
// it in the current context.
func runInCgroup(cg cgroup.Cgroup, fn func() error) error {
if cg == nil {
return fn()
}
restore, err := cg.Join()
if err != nil {
return err
}
defer restore()
return fn()
}
// adjustGoferOOMScoreAdj sets the oom_store_adj for the container's gofer.
func (c *Container) adjustGoferOOMScoreAdj() error {
if c.GoferPid == 0 || c.Spec.Process.OOMScoreAdj == nil {
return nil
}
return setOOMScoreAdj(c.GoferPid, *c.Spec.Process.OOMScoreAdj)
}
// adjustSandboxOOMScoreAdj sets the oom_score_adj for the sandbox.
// oom_score_adj is set to the lowest oom_score_adj among the containers
// running in the sandbox.
//
// TODO(gvisor.dev/issue/238): This call could race with other containers being
// created at the same time and end up setting the wrong oom_score_adj to the
// sandbox. Use rpc client to synchronize.
func adjustSandboxOOMScoreAdj(s *sandbox.Sandbox, spec *specs.Spec, rootDir string, destroy bool) error {
// Adjustment can be skipped if the root container is exiting, because it
// brings down the entire sandbox.
if isRoot(spec) && destroy {
return nil
}
containers, err := LoadSandbox(rootDir, s.ID, LoadOpts{})
if err != nil {
return fmt.Errorf("loading sandbox containers: %v", err)
}
// Do nothing if the sandbox has been terminated.
if len(containers) == 0 {
return nil
}
// Get the lowest score for all containers.
var lowScore int
scoreFound := false
for _, container := range containers {
// Special multi-container support for CRI. Ignore the root container when
// calculating oom_score_adj for the sandbox because it is the
// infrastructure (pause) container and always has a very low oom_score_adj.
//
// We will use OOMScoreAdj in the single-container case where the
// containerd container-type annotation is not present.
if specutils.SpecContainerType(container.Spec) == specutils.ContainerTypeSandbox {
continue
}
if container.Spec.Process.OOMScoreAdj != nil && (!scoreFound || *container.Spec.Process.OOMScoreAdj < lowScore) {
scoreFound = true
lowScore = *container.Spec.Process.OOMScoreAdj
}
}
// If the container is destroyed and remaining containers have no
// oomScoreAdj specified then we must revert to the original oom_score_adj
// saved with the root container.
if !scoreFound && destroy {
lowScore = containers[0].Sandbox.OriginalOOMScoreAdj
scoreFound = true
}
// Only set oom_score_adj if one of the containers has oom_score_adj set. If
// not, oom_score_adj is inherited from the parent process.
//
// See: https://github.com/opencontainers/runtime-spec/blob/master/config.md#linux-process
if !scoreFound {
return nil
}
// Set the lowest of all containers oom_score_adj to the sandbox.
return setOOMScoreAdj(s.Getpid(), lowScore)
}
// setOOMScoreAdj sets oom_score_adj to the given value for the given PID.
// /proc must be available and mounted read-write. scoreAdj should be between
// -1000 and 1000. It's a noop if the process has already exited.
func setOOMScoreAdj(pid int, scoreAdj int) error {
f, err := os.OpenFile(fmt.Sprintf("/proc/%d/oom_score_adj", pid), os.O_WRONLY, 0644)
if err != nil {
// Ignore NotExist errors because it can race with process exit.
if os.IsNotExist(err) {
log.Warningf("Process (%d) not found setting oom_score_adj", pid)
return nil
}
return err
}
defer f.Close()
if _, err := f.WriteString(strconv.Itoa(scoreAdj)); err != nil {
if errors.Is(err, unix.ESRCH) {
log.Warningf("Process (%d) exited while setting oom_score_adj", pid)
return nil
}
return fmt.Errorf("setting oom_score_adj to %q: %v", scoreAdj, err)
}
return nil
}
// populateStats populates event with stats estimates based on cgroups and the
// sentry's accounting.
func (c *Container) populateStats(event *boot.EventOut) {
// The events command, when run for all running containers, should
// account for the full cgroup CPU usage. We split cgroup usage
// proportionally according to the sentry-internal usage measurements,
// only counting Running containers.
log.Debugf("event.ContainerUsage: %v", event.ContainerUsage)
numContainers := uint64(len(event.ContainerUsage))
if numContainers == 0 {
log.Warningf("events: no containers listed in usage, returning zero CPU usage")
event.Event.Data.CPU.Usage.Total = 0
return
}
var containerUsage uint64
var allContainersUsage uint64
for ID, usage := range event.ContainerUsage {
allContainersUsage += usage
if ID == c.ID {
containerUsage = usage
}
}
cgroup, err := c.Sandbox.NewCGroup()
if err != nil {
// No cgroup, so rely purely on the sentry's accounting.
log.Warningf("events: no cgroups")
event.Event.Data.CPU.Usage.Total = containerUsage
return
}
// Get the host cgroup CPU usage.
cgroupsUsage, err := cgroup.CPUUsage()
if err != nil || cgroupsUsage == 0 {
// No cgroup usage, so rely purely on the sentry's accounting.
log.Warningf("events: failed when getting cgroup CPU usage for container: usage=%d, err: %v", cgroupsUsage, err)
event.Event.Data.CPU.Usage.Total = containerUsage
return
}
// If the sentry reports no CPU usage, fall back on cgroups and split usage
// equally across containers.
if allContainersUsage == 0 {
log.Warningf("events: no sentry CPU usage reported")
allContainersUsage = cgroupsUsage
containerUsage = cgroupsUsage / numContainers
}
// Scaling can easily overflow a uint64 (e.g. a containerUsage and
// cgroupsUsage of 16 seconds each will overflow), so use floats.
total := float64(containerUsage) * (float64(cgroupsUsage) / float64(allContainersUsage))
log.Debugf("Usage, container: %d, cgroups: %d, all: %d, total: %.0f", containerUsage, cgroupsUsage, allContainersUsage, total)
event.Event.Data.CPU.Usage.Total = uint64(total)
return
}
func (c *Container) createParentCgroup(parentPath string, conf *config.Config) (cgroup.Cgroup, error) {
var err error
if conf.SystemdCgroup {
parentPath, err = cgroup.TransformSystemdPath(parentPath, c.ID, conf.Rootless)
if err != nil {
return nil, err
}
} else if cgroup.LikelySystemdPath(parentPath) {
log.Warningf("cgroup parent path is set to %q which looks like a systemd path. Please set --systemd-cgroup=true if you intend to use systemd to manage container cgroups", parentPath)
}
parentCgroup, err := cgroup.NewFromPath(parentPath, conf.SystemdCgroup)
if err != nil {
return nil, err
}
return parentCgroup, nil
}
// setupCgroupForRoot configures and returns cgroup for the sandbox and the
// root container. If `cgroupParentAnnotation` is set, use that path as the
// sandbox cgroup and use Spec.Linux.CgroupsPath as the root container cgroup.
func (c *Container) setupCgroupForRoot(conf *config.Config, spec *specs.Spec) (cgroup.Cgroup, cgroup.Cgroup, error) {
var parentCgroup cgroup.Cgroup
if parentPath, ok := spec.Annotations[cgroupParentAnnotation]; ok {
var err error
parentCgroup, err = c.createParentCgroup(parentPath, conf)
if err != nil {
return nil, nil, err
}
} else {
var err error
if spec.Linux == nil || spec.Linux.CgroupsPath == "" {
return nil, nil, nil
}
parentCgroup, err = c.createParentCgroup(spec.Linux.CgroupsPath, conf)
if parentCgroup == nil || err != nil {
return nil, nil, err
}
}
var err error
parentCgroup, err = cgroupInstall(conf, parentCgroup, spec.Linux.Resources)
if parentCgroup == nil || err != nil {
return nil, nil, err
}
subCgroup, err := c.setupCgroupForSubcontainer(conf, spec)
if err != nil {
_ = parentCgroup.Uninstall()
return nil, nil, err
}
return parentCgroup, subCgroup, nil
}
// setupCgroupForSubcontainer sets up empty cgroups for subcontainers. Since
// subcontainers run exclusively inside the sandbox, subcontainer cgroups on the
// host have no effect on them. However, some tools (e.g. cAdvisor) uses cgroups
// paths to discover new containers and report stats for them.
func (c *Container) setupCgroupForSubcontainer(conf *config.Config, spec *specs.Spec) (cgroup.Cgroup, error) {
if isRoot(spec) {
if _, ok := spec.Annotations[cgroupParentAnnotation]; !ok {
return nil, nil
}
}
if spec.Linux == nil || spec.Linux.CgroupsPath == "" {
return nil, nil
}
cg, err := c.createParentCgroup(spec.Linux.CgroupsPath, conf)
if cg == nil || err != nil {
return nil, err
}
// Use empty resources, just want the directory structure created.
return cgroupInstall(conf, cg, &specs.LinuxResources{})
}
// donateGoferProfileFDs will open profile files and donate their FDs to the
// gofer.
func (c *Container) donateGoferProfileFDs(conf *config.Config, donations *donation.Agency) error {
// The gofer profile files are named based on the provided flag, but
// suffixed with "gofer" and the container ID to avoid collisions with
// sentry profile files or profile files from other gofers.
//
// TODO(b/243183772): Merge gofer profile data with sentry profile data
// into a single file.
profSuffix := ".gofer." + c.ID
const profFlags = os.O_CREATE | os.O_WRONLY | os.O_TRUNC
profile.UpdatePaths(conf, starttime.Get())
if conf.ProfileBlock != "" {
if err := donations.OpenAndDonate("profile-block-fd", conf.ProfileBlock+profSuffix, profFlags); err != nil {
return err
}
}
if conf.ProfileCPU != "" {
if err := donations.OpenAndDonate("profile-cpu-fd", conf.ProfileCPU+profSuffix, profFlags); err != nil {
return err
}
}
if conf.ProfileHeap != "" {
if err := donations.OpenAndDonate("profile-heap-fd", conf.ProfileHeap+profSuffix, profFlags); err != nil {
return err
}
}
if conf.ProfileMutex != "" {
if err := donations.OpenAndDonate("profile-mutex-fd", conf.ProfileMutex+profSuffix, profFlags); err != nil {
return err
}
}
if conf.TraceFile != "" {
if err := donations.OpenAndDonate("trace-fd", conf.TraceFile+profSuffix, profFlags); err != nil {
return err
}
}
return nil
}
// cgroupInstall creates cgroups dir structure and sets their respective
// resources. In case of success, returns the cgroups instance and nil error.
// For rootless, it's possible that cgroups operations fail, in this case the
// error is suppressed and a nil cgroups instance is returned to indicate that
// no cgroups was configured.
func cgroupInstall(conf *config.Config, cg cgroup.Cgroup, res *specs.LinuxResources) (cgroup.Cgroup, error) {
if err := cg.Install(res); err != nil {
switch {
case (errors.Is(err, unix.EACCES) || errors.Is(err, unix.EROFS)) && conf.Rootless:
log.Warningf("Skipping cgroup configuration in rootless mode: %v", err)
return nil, nil
default:
return nil, fmt.Errorf("configuring cgroup: %v", err)
}
}
return cg, nil
}
func modifySpecForDirectfs(conf *config.Config, spec *specs.Spec) error {
if !conf.DirectFS || conf.TestOnlyAllowRunAsCurrentUserWithoutChroot {
return nil
}
if conf.Network == config.NetworkHost {
// Hostnet feature requires the sandbox to run in the current user
// namespace, in which the network namespace is configured.
return nil
}
if _, ok := specutils.GetNS(specs.UserNamespace, spec); ok {
// If the spec already defines a userns, use that.
return nil
}
if spec.Linux == nil {
spec.Linux = &specs.Linux{}
}
if len(spec.Linux.UIDMappings) > 0 || len(spec.Linux.GIDMappings) > 0 {
// The spec can only define UID/GID mappings with a userns (checked above).
return fmt.Errorf("spec defines UID/GID mappings without defining userns")
}
// Run the sandbox in a new user namespace with identity UID/GID mappings.
log.Debugf("Configuring container with a new userns with identity user mappings into current userns")
spec.Linux.Namespaces = append(spec.Linux.Namespaces, specs.LinuxNamespace{Type: specs.UserNamespace})
uidMappings, err := getIdentityMapping("uid_map")
if err != nil {
return err
}
spec.Linux.UIDMappings = uidMappings
logIDMappings(uidMappings, "UID")
gidMappings, err := getIdentityMapping("gid_map")
if err != nil {
return err
}
spec.Linux.GIDMappings = gidMappings
logIDMappings(gidMappings, "GID")
return nil
}
func getIdentityMapping(mapFileName string) ([]specs.LinuxIDMapping, error) {
// See user_namespaces(7) to understand how /proc/self/{uid/gid}_map files
// are organized.
mapFile := path.Join("/proc/self", mapFileName)
file, err := os.Open(mapFile)
if err != nil {
return nil, fmt.Errorf("failed to open %s: %v", mapFile, err)
}
defer file.Close()
var mappings []specs.LinuxIDMapping
scanner := bufio.NewScanner(file)
for scanner.Scan() {
line := scanner.Text()
var myStart, parentStart, rangeLen uint32
numParsed, err := fmt.Sscanf(line, "%d %d %d", &myStart, &parentStart, &rangeLen)
if err != nil {
return nil, fmt.Errorf("failed to parse line %q in file %s: %v", line, mapFile, err)
}
if numParsed != 3 {
return nil, fmt.Errorf("failed to parse 3 integers from line %q in file %s", line, mapFile)
}
// Create an identity mapping with the current userns.
mappings = append(mappings, specs.LinuxIDMapping{
ContainerID: myStart,
HostID: myStart,
Size: rangeLen,
})
}
if err := scanner.Err(); err != nil {
return nil, fmt.Errorf("failed to scan file %s: %v", mapFile, err)
}
return mappings, nil
}
func logIDMappings(mappings []specs.LinuxIDMapping, idType string) {
if !log.IsLogging(log.Debug) {
return
}
log.Debugf("%s Mappings:", idType)
for _, m := range mappings {
log.Debugf("\tContainer ID: %d, Host ID: %d, Range Length: %d", m.ContainerID, m.HostID, m.Size)
}
}
// nvProxyPreGoferHostSetup does host setup work so that `nvidia-container-cli
// configure` can be run in the future. It runs before any Gofers start.
// It verifies that all the required dependencies are in place, loads kernel
// modules, and ensures the correct device files exist and are accessible.
// This should only be necessary once on the host. It should be run during the
// root container setup sequence to make sure it has run at least once.
func nvProxyPreGoferHostSetup(spec *specs.Spec, conf *config.Config) error {
if !specutils.GPUFunctionalityRequestedViaHook(spec, conf) {
return nil
}
// Locate binaries. For security reasons, unlike
// nvidia-container-runtime-hook, we don't add the container's filesystem
// to the search path. We also don't support
// /etc/nvidia-container-runtime/config.toml to avoid importing a TOML
// parser.
cliPath, err := exec.LookPath("nvidia-container-cli")
if err != nil {
return fmt.Errorf("failed to locate nvidia-container-cli in PATH: %w", err)
}
// nvidia-container-cli --load-kmods seems to be a noop; load kernel modules ourselves.
nvproxyLoadKernelModules()
if _, err := os.Stat("/dev/nvidiactl"); err != nil {
if !os.IsNotExist(err) {
return fmt.Errorf("stat(2) for /dev/nvidiactl failed: %w", err)
}
// Run `nvidia-container-cli info`.
// This has the side-effect of automatically creating GPU device files.
argv := []string{cliPath, "--load-kmods", "info"}
log.Debugf("Executing %q", argv)
var infoOut, infoErr strings.Builder
cmd := exec.Cmd{
Path: argv[0],
Args: argv,
Env: os.Environ(),
Stdout: &infoOut,
Stderr: &infoErr,
}
if err := cmd.Run(); err != nil {
return fmt.Errorf("nvidia-container-cli info failed, err: %v\nstdout: %s\nstderr: %s", err, infoOut.String(), infoErr.String())
}
log.Debugf("nvidia-container-cli info: %v", infoOut.String())
}
return nil
}
// nvproxyLoadKernelModules loads NVIDIA-related kernel modules with modprobe.
func nvproxyLoadKernelModules() {
for _, mod := range [...]string{
"nvidia",
"nvidia-uvm",
} {
argv := []string{
"/sbin/modprobe",
mod,
}
log.Debugf("Executing %q", argv)
var stdout, stderr strings.Builder
cmd := exec.Cmd{
Path: argv[0],
Args: argv,
Env: os.Environ(),
Stdout: &stdout,
Stderr: &stderr,
}
if err := cmd.Run(); err != nil {
// This might not be fatal since modules may already be loaded. Log
// the failure but continue.
log.Warningf("modprobe %s failed, err: %v\nstdout: %s\nstderr: %s", mod, err, stdout.String(), stderr.String())
}
}
}
// nvproxySetupAfterGoferUserns runs `nvidia-container-cli configure`.
// This sets up the container filesystem with bind mounts that allow it to
// use NVIDIA devices.
//
// This should be called during the Gofer setup process, as the bind mounts
// are created in the Gofer's mount namespace.
// If successful, it returns a callback function that must be called once the
// Gofer process has started.
// This function has no effect if nvproxy functionality is not requested.
//
// This function essentially replicates
// nvidia-container-toolkit:cmd/nvidia-container-runtime-hook, i.e. the
// binary that executeHook() is hard-coded to skip, with differences noted
// inline. We do this rather than move the prestart hook because the
// "runtime environment" in which prestart hooks execute is vaguely
// defined, such that nvidia-container-runtime-hook and existing runsc
// hooks differ in their expected environment.
//
// Note that nvidia-container-cli will set up files in /dev and /proc which
// are useless, since they will be hidden by sentry devtmpfs and procfs
// respectively (and some device files will have the wrong device numbers
// from the application's perspective since nvproxy may register device
// numbers in sentry VFS that differ from those on the host, e.g. for
// nvidia-uvm). These files are separately created during sandbox VFS
// construction. For this reason, we don't need to parse
// NVIDIA_VISIBLE_DEVICES or pass --device to nvidia-container-cli.
func nvproxySetupAfterGoferUserns(spec *specs.Spec, conf *config.Config, goferCmd *exec.Cmd, goferDonations *donation.Agency) (func() error, error) {
if !specutils.GPUFunctionalityRequestedViaHook(spec, conf) {
return func() error { return nil }, nil
}
if spec.Root == nil {
return nil, fmt.Errorf("spec missing root filesystem")
}
// nvidia-container-cli does not create this directory.
if err := os.MkdirAll(path.Join(spec.Root.Path, "proc", "driver", "nvidia"), 0555); err != nil {
return nil, fmt.Errorf("failed to create /proc/driver/nvidia in app filesystem: %w", err)
}
cliPath, err := exec.LookPath("nvidia-container-cli")
if err != nil {
return nil, fmt.Errorf("failed to locate nvidia-container-cli in PATH: %w", err)
}
// On Ubuntu, ldconfig is a wrapper around ldconfig.real, and we need the latter.
var ldconfigPath string
if _, err := os.Stat("/sbin/ldconfig.real"); err == nil {
ldconfigPath = "/sbin/ldconfig.real"
} else {
ldconfigPath = "/sbin/ldconfig"
}
devices, err := specutils.ParseNvidiaVisibleDevices(spec)
if err != nil {
return nil, fmt.Errorf("failed to get nvidia device numbers: %w", err)
}
// Create synchronization FD for nvproxy.
fds, err := unix.Socketpair(unix.AF_UNIX, unix.SOCK_STREAM|unix.SOCK_CLOEXEC, 0)
if err != nil {
return nil, err
}
ourEnd := os.NewFile(uintptr(fds[0]), "nvproxy sync runsc FD")
goferEnd := os.NewFile(uintptr(fds[1]), "nvproxy sync gofer FD")
goferDonations.DonateAndClose("sync-nvproxy-fd", goferEnd)
return func() error {
defer ourEnd.Close()
argv := []string{
cliPath,
"--load-kmods",
"configure",
fmt.Sprintf("--ldconfig=@%s", ldconfigPath),
"--no-cgroups", // runsc doesn't configure device cgroups yet
"--utility",
"--compute",
fmt.Sprintf("--pid=%d", goferCmd.Process.Pid),
fmt.Sprintf("--device=%s", devices),
spec.Root.Path,
}
log.Debugf("Executing %q", argv)
var stdout, stderr strings.Builder
cmd := exec.Cmd{
Path: argv[0],
Args: argv,
Env: os.Environ(),
Stdout: &stdout,
Stderr: &stderr,
}
if err := cmd.Run(); err != nil {
return fmt.Errorf("nvidia-container-cli configure failed, err: %v\nstdout: %s\nstderr: %s", err, stdout.String(), stderr.String())
}
return nil
}, nil
}
// CheckStopped checks if the container is stopped and updates its status.
func (c *Container) CheckStopped() {
if state, err := c.Sandbox.ContainerRuntimeState(c.ID); err != nil {
log.Warningf("Cannot find if container %v exists, checking if sandbox %v is running, err: %v", c.ID, c.Sandbox.ID, err)
if !c.IsSandboxRunning() {
log.Warningf("Sandbox isn't running anymore, marking container %v as stopped:", c.ID)
c.changeStatus(Stopped)
}
} else {
if state == boot.RuntimeStateStopped {
log.Warningf("Container %v is stopped", c.ID)
c.changeStatus(Stopped)
}
}
}
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