diff options
Diffstat (limited to 'runsc/sandbox/sandbox.go')
| -rw-r--r-- | runsc/sandbox/sandbox.go | 31 |
1 files changed, 9 insertions, 22 deletions
diff --git a/runsc/sandbox/sandbox.go b/runsc/sandbox/sandbox.go index 8de75ae57..3b06da98b 100644 --- a/runsc/sandbox/sandbox.go +++ b/runsc/sandbox/sandbox.go @@ -588,45 +588,32 @@ func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncF nss = append(nss, specs.LinuxNamespace{Type: specs.UserNamespace}) cmd.Args = append(cmd.Args, "--setup-root") + const nobody = 65534 if conf.Rootless { - log.Infof("Rootless mode: sandbox will run as root inside user namespace, mapped to the current user, uid: %d, gid: %d", os.Getuid(), os.Getgid()) + log.Infof("Rootless mode: sandbox will run as nobody inside user namespace, mapped to the current user, uid: %d, gid: %d", os.Getuid(), os.Getgid()) cmd.SysProcAttr.UidMappings = []syscall.SysProcIDMap{ { - ContainerID: 0, + ContainerID: nobody, HostID: os.Getuid(), Size: 1, }, } cmd.SysProcAttr.GidMappings = []syscall.SysProcIDMap{ { - ContainerID: 0, + ContainerID: nobody, HostID: os.Getgid(), Size: 1, }, } - cmd.SysProcAttr.Credential = &syscall.Credential{Uid: 0, Gid: 0} } else { // Map nobody in the new namespace to nobody in the parent namespace. // // A sandbox process will construct an empty - // root for itself, so it has to have the CAP_SYS_ADMIN - // capability. - // - // FIXME(b/122554829): The current implementations of - // os/exec doesn't allow to set ambient capabilities if - // a process is started in a new user namespace. As a - // workaround, we start the sandbox process with the 0 - // UID and then it constructs a chroot and sets UID to - // nobody. https://github.com/golang/go/issues/2315 - const nobody = 65534 + // root for itself, so it has to have + // CAP_SYS_ADMIN and CAP_SYS_CHROOT capabilities. cmd.SysProcAttr.UidMappings = []syscall.SysProcIDMap{ { - ContainerID: 0, - HostID: nobody - 1, - Size: 1, - }, - { ContainerID: nobody, HostID: nobody, Size: 1, @@ -639,11 +626,11 @@ func (s *Sandbox) createSandboxProcess(conf *boot.Config, args *Args, startSyncF Size: 1, }, } - - // Set credentials to run as user and group nobody. - cmd.SysProcAttr.Credential = &syscall.Credential{Uid: 0, Gid: nobody} } + // Set credentials to run as user and group nobody. + cmd.SysProcAttr.Credential = &syscall.Credential{Uid: nobody, Gid: nobody} + cmd.SysProcAttr.AmbientCaps = append(cmd.SysProcAttr.AmbientCaps, uintptr(capability.CAP_SYS_ADMIN), uintptr(capability.CAP_SYS_CHROOT)) } else { return fmt.Errorf("can't run sandbox process as user nobody since we don't have CAP_SETUID or CAP_SETGID") } |