Andrey Vagin <[email protected]> writes:

> diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c
> index 3529a03..a63adfb 100644
> --- a/kernel/pid_namespace.c
> +++ b/kernel/pid_namespace.c
> @@ -388,12 +388,38 @@ static int pidns_install(struct nsproxy *nsproxy, 
> struct ns_common *ns)
>       return 0;
>  }
>  
> +static struct ns_common *pidns_get_parent(struct ns_common *ns)
> +{
> +     struct pid_namespace *active = task_active_pid_ns(current);
> +     struct pid_namespace *pid_ns, *p;
> +
> +     pid_ns = to_pid_ns(ns);
> +     if (pid_ns == &init_pid_ns) {
> +             if (capable(CAP_SYS_ADMIN))
> +                     return ERR_PTR(-ENOENT);
> +             return ERR_PTR(-EPERM);
> +     }
> +
> +     pid_ns = p = pid_ns->parent;
> +
> +     for (;;) {
> +             if (p == active)
> +                     break;
> +             if (p == &init_pid_ns)
> +                     return ERR_PTR(-EPERM);
> +             p = p->parent;
> +     }

Similarly to the user namespace issue the permission check here needs to
be:
        if (!ns_capable(pid_ns->user_ns, CAP_SYS_ADMIN)
                return ERR_PTR(-EPERM);
> +
> +     return &get_pid_ns(pid_ns)->ns;
> +}
> +
>  const struct proc_ns_operations pidns_operations = {
>       .name           = "pid",
>       .type           = CLONE_NEWPID,
>       .get            = pidns_get,
>       .put            = pidns_put,
>       .install        = pidns_install,
> +     .get_parent     = pidns_get_parent,
>  };
>  

Eric

Reply via email to