// RestoreParentDeathSignal sets the parent death signal to old.
func RestoreParentDeathSignal(old int) error {
if old == 0 {
return nil
}
current, err := system.GetParentDeathSignal()
if err != nil {
return fmt.Errorf("get parent death signal %s", err)
}
if old == current {
return nil
}
if err := system.ParentDeathSignal(uintptr(old)); err != nil {
return fmt.Errorf("set parent death signal %s", err)
}
// Signal self if parent is already dead. Does nothing if running in a new
// PID namespace, as Getppid will always return 0.
if syscall.Getppid() == 1 {
return syscall.Kill(syscall.Getpid(), syscall.SIGKILL)
}
return nil
}
// Init is the init process that first runs inside a new namespace to setup mounts, users, networking,
// and other options required for the new container.
func (ns *linuxNs) Init(container *libcontainer.Container, uncleanRootfs, console string, syncPipe *SyncPipe, args []string) error {
rootfs, err := utils.ResolveRootfs(uncleanRootfs)
if err != nil {
return err
}
// We always read this as it is a way to sync with the parent as well
context, err := syncPipe.ReadFromParent()
if err != nil {
syncPipe.Close()
return err
}
syncPipe.Close()
if console != "" {
slave, err := system.OpenTerminal(console, syscall.O_RDWR)
if err != nil {
return fmt.Errorf("open terminal %s", err)
}
if err := dupSlave(slave); err != nil {
return fmt.Errorf("dup2 slave %s", err)
}
}
if _, err := system.Setsid(); err != nil {
return fmt.Errorf("setsid %s", err)
}
if console != "" {
if err := system.Setctty(); err != nil {
return fmt.Errorf("setctty %s", err)
}
}
// this is our best effort to let the process know that the parent has died and that it
// should it should act on it how it sees fit
if err := system.ParentDeathSignal(uintptr(syscall.SIGTERM)); err != nil {
return fmt.Errorf("parent death signal %s", err)
}
if err := setupNewMountNamespace(rootfs, container.Mounts, console, container.ReadonlyFs, container.NoPivotRoot); err != nil {
return fmt.Errorf("setup mount namespace %s", err)
}
if err := setupNetwork(container, context); err != nil {
return fmt.Errorf("setup networking %s", err)
}
if err := system.Sethostname(container.Hostname); err != nil {
return fmt.Errorf("sethostname %s", err)
}
if err := finalizeNamespace(container); err != nil {
return fmt.Errorf("finalize namespace %s", err)
}
if err := apparmor.ApplyProfile(os.Getpid(), container.Context["apparmor_profile"]); err != nil {
return err
}
return system.Execv(args[0], args[0:], container.Env)
}
// Init is the init process that first runs inside a new namespace to setup mounts, users, networking,
// and other options required for the new container.
func (ns *linuxNs) Init(container *libcontainer.Container, uncleanRootfs, console string, syncPipe *SyncPipe, args []string) error {
rootfs, err := utils.ResolveRootfs(uncleanRootfs)
if err != nil {
return err
}
// We always read this as it is a way to sync with the parent as well
ns.logger.Printf("reading from sync pipe fd %d\n", syncPipe.child.Fd())
context, err := syncPipe.ReadFromParent()
if err != nil {
syncPipe.Close()
return err
}
ns.logger.Println("received context from parent")
syncPipe.Close()
if console != "" {
ns.logger.Printf("setting up %s as console\n", console)
slave, err := system.OpenTerminal(console, syscall.O_RDWR)
if err != nil {
return fmt.Errorf("open terminal %s", err)
}
if err := dupSlave(slave); err != nil {
return fmt.Errorf("dup2 slave %s", err)
}
}
if _, err := system.Setsid(); err != nil {
return fmt.Errorf("setsid %s", err)
}
if console != "" {
if err := system.Setctty(); err != nil {
return fmt.Errorf("setctty %s", err)
}
}
// this is our best effort to let the process know that the parent has died and that it
// should it should act on it how it sees fit
if err := system.ParentDeathSignal(uintptr(syscall.SIGTERM)); err != nil {
return fmt.Errorf("parent death signal %s", err)
}
ns.logger.Println("setup mount namespace")
if err := setupNewMountNamespace(rootfs, container.Mounts, console, container.ReadonlyFs, container.NoPivotRoot, container.Context["mount_label"]); err != nil {
return fmt.Errorf("setup mount namespace %s", err)
}
if err := setupNetwork(container, context); err != nil {
return fmt.Errorf("setup networking %s", err)
}
if err := system.Sethostname(container.Hostname); err != nil {
return fmt.Errorf("sethostname %s", err)
}
if err := finalizeNamespace(container); err != nil {
return fmt.Errorf("finalize namespace %s", err)
}
if profile := container.Context["apparmor_profile"]; profile != "" {
ns.logger.Printf("setting apparmor profile %s\n", profile)
if err := apparmor.ApplyProfile(os.Getpid(), profile); err != nil {
return err
}
}
runtime.LockOSThread()
if err := label.SetProcessLabel(container.Context["process_label"]); err != nil {
return fmt.Errorf("SetProcessLabel label %s", err)
}
ns.logger.Printf("execing %s\n", args[0])
return system.Execv(args[0], args[0:], container.Env)
}