Exemplo n.º 1
0
func MsMoveRoot(rootfs string) error {
	if err := system.Mount(rootfs, "/", "", syscall.MS_MOVE, ""); err != nil {
		return fmt.Errorf("mount move %s into / %s", rootfs, err)
	}
	if err := system.Chroot("."); err != nil {
		return fmt.Errorf("chroot . %s", err)
	}
	return system.Chdir("/")
}
Exemplo n.º 2
0
// setupNewMountNamespace is used to initialize a new mount namespace for an new
// container in the rootfs that is specified.
//
// There is no need to unmount the new mounts because as soon as the mount namespace
// is no longer in use, the mounts will be removed automatically
func setupNewMountNamespace(rootfs, console string, readonly bool) error {
	// mount as slave so that the new mounts do not propagate to the host
	if err := system.Mount("", "/", "", syscall.MS_SLAVE|syscall.MS_REC, ""); err != nil {
		return fmt.Errorf("mounting / as slave %s", err)
	}
	if err := system.Mount(rootfs, rootfs, "bind", syscall.MS_BIND|syscall.MS_REC, ""); err != nil {
		return fmt.Errorf("mouting %s as bind %s", rootfs, err)
	}
	if readonly {
		if err := system.Mount(rootfs, rootfs, "bind", syscall.MS_BIND|syscall.MS_REMOUNT|syscall.MS_RDONLY|syscall.MS_REC, ""); err != nil {
			return fmt.Errorf("mounting %s as readonly %s", rootfs, err)
		}
	}
	if err := mountSystem(rootfs); err != nil {
		return fmt.Errorf("mount system %s", err)
	}
	if err := copyDevNodes(rootfs); err != nil {
		return fmt.Errorf("copy dev nodes %s", err)
	}
	// In non-privileged mode, this fails. Discard the error.
	setupLoopbackDevices(rootfs)
	if err := setupDev(rootfs); err != nil {
		return err
	}
	if console != "" {
		if err := setupPtmx(rootfs, console); err != nil {
			return err
		}
	}
	if err := system.Chdir(rootfs); err != nil {
		return fmt.Errorf("chdir into %s %s", rootfs, err)
	}
	if err := system.Mount(rootfs, "/", "", syscall.MS_MOVE, ""); err != nil {
		return fmt.Errorf("mount move %s into / %s", rootfs, err)
	}
	if err := system.Chroot("."); err != nil {
		return fmt.Errorf("chroot . %s", err)
	}
	if err := system.Chdir("/"); err != nil {
		return fmt.Errorf("chdir / %s", err)
	}

	system.Umask(0022)

	return nil
}