Andrey Vagin <avagin@xxxxxxxxxx> 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 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html