Files
runc/libcontainer/setns_init_linux.go
Daniel J Walsh aa3fee6c80 SELinux labels are tied to the thread
We need to lock the threads for the SetProcessLabel to work,
should also call SetProcessLabel("") after the container starts
to go back to the default SELinux behaviour.

Once you call SetProcessLabel, then any process executed by runc
will run with this label, even if the process is for setup rather
then the container.

It is always safest to call the SELinux calls just before the exec of the
container, so that other processes do not get started with the incorrect label.

Signed-off-by: Daniel J Walsh <dwalsh@redhat.com>
2018-06-11 08:34:58 -04:00

82 lines
2.4 KiB
Go

// +build linux
package libcontainer
import (
"fmt"
"os"
"runtime"
"github.com/opencontainers/runc/libcontainer/apparmor"
"github.com/opencontainers/runc/libcontainer/keys"
"github.com/opencontainers/runc/libcontainer/seccomp"
"github.com/opencontainers/runc/libcontainer/system"
"github.com/opencontainers/selinux/go-selinux/label"
"golang.org/x/sys/unix"
)
// linuxSetnsInit performs the container's initialization for running a new process
// inside an existing container.
type linuxSetnsInit struct {
pipe *os.File
consoleSocket *os.File
config *initConfig
}
func (l *linuxSetnsInit) getSessionRingName() string {
return fmt.Sprintf("_ses.%s", l.config.ContainerId)
}
func (l *linuxSetnsInit) Init() error {
runtime.LockOSThread()
defer runtime.UnlockOSThread()
if !l.config.Config.NoNewKeyring {
// do not inherit the parent's session keyring
if _, err := keys.JoinSessionKeyring(l.getSessionRingName()); err != nil {
return err
}
}
if l.config.CreateConsole {
if err := setupConsole(l.consoleSocket, l.config, false); err != nil {
return err
}
if err := system.Setctty(); err != nil {
return err
}
}
if l.config.NoNewPrivileges {
if err := unix.Prctl(unix.PR_SET_NO_NEW_PRIVS, 1, 0, 0, 0); err != nil {
return err
}
}
if err := label.SetProcessLabel(l.config.ProcessLabel); err != nil {
return err
}
defer label.SetProcessLabel("")
// Without NoNewPrivileges seccomp is a privileged operation, so we need to
// do this before dropping capabilities; otherwise do it as late as possible
// just before execve so as few syscalls take place after it as possible.
if l.config.Config.Seccomp != nil && !l.config.NoNewPrivileges {
if err := seccomp.InitSeccomp(l.config.Config.Seccomp); err != nil {
return err
}
}
if err := finalizeNamespace(l.config); err != nil {
return err
}
if err := apparmor.ApplyProfile(l.config.AppArmorProfile); err != nil {
return err
}
// Set seccomp as close to execve as possible, so as few syscalls take
// place afterward (reducing the amount of syscalls that users need to
// enable in their seccomp profiles).
if l.config.Config.Seccomp != nil && l.config.NoNewPrivileges {
if err := seccomp.InitSeccomp(l.config.Config.Seccomp); err != nil {
return newSystemErrorWithCause(err, "init seccomp")
}
}
return system.Execv(l.config.Args[0], l.config.Args[0:], os.Environ())
}