On 09/15, Konstantin Khlebnikov wrote: > > +SYSCALL_DEFINE3(getvpid, pid_t, pid, pid_t, source, pid_t, target) > +{ > +#ifdef CONFIG_PID_NS > + struct pid_namespace *current_ns = task_active_pid_ns(current); > + struct pid_namespace *source_ns = current_ns, *target_ns = current_ns; > + struct pid *task_pid; > + pid_t result = -ESRCH; > + > + rcu_read_lock(); > + if (source) > + source_ns = ns_of_pid(find_pid_ns(source, current_ns)); > + if (target) > + target_ns = ns_of_pid(find_pid_ns(target, current_ns)); > + if (source_ns && target_ns) { > + task_pid = find_pid_ns(pid, source_ns); > + if (task_pid) > + result = pid_nr_ns(task_pid, target_ns); > + } > + rcu_read_unlock(); > + > + return result; > +#else > + return pid; > +#endif /* CONFIG_PID_NS */ > +} Not sure we actually want ifdef(CONFIG_PID_NS). If this is just optimization I'd suggest to simply add if (!IS_ENABLED(CONFIG_PID_NS)) return pid; at the start. But. Either way this unconditional "return pid" doesn't look right imho. I think we should return -ESRCH if this pid number is not valid to ensure we have the same semantics with-or-without CONFIG_PID_NS. So it seems that you should remove this ifdef, this will also ensure that we return -ESRCH if (say) source != 0 and find_pid_ns(source) fails. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html