Function Getgroups

pkg/sentry/syscalls/linux/sys_identity.go:142–164

Getgroups implements the Linux syscall getgroups.

(t *kernel.Task, sysno uintptr, args arch.SyscallArguments)

// Getgroups implements the Linux syscall getgroups.
func Getgroups(t *kernel.Task, sysno uintptr, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {
	size := int(args[0].Int())
	if size < 0 {
		return 0, nil, linuxerr.EINVAL
	}
	kgids := t.Credentials().ExtraKGIDs
	// "If size is zero, list is not modified, but the total number of
	// supplementary group IDs for the process is returned." - getgroups(2)
	if size == 0 {
		return uintptr(len(kgids)), nil, nil
	}
	if size < len(kgids) {
		return 0, nil, linuxerr.EINVAL
	}
	gids := make([]auth.GID, len(kgids))
	for i, kgid := range kgids {
		gids[i] = kgid.In(t.UserNamespace()).OrOverflow()
	}
	if _, err := auth.CopyGIDSliceOut(t, args[1].Pointer(), gids); err != nil {
		return 0, nil, err
	}
	return uintptr(len(gids)), nil, nil
}

// Setgroups implements the Linux syscall setgroups.
func Setgroups(t *kernel.Task, sysno uintptr, args arch.SyscallArguments) (uintptr, *kernel.SyscallControl, error) {