> +/***
> + * good_sigevent - check and get target task from a sigevent.
> + * @event: the sigevent to be checked
> + *
> + * This function must be called with tasklist_lock held for reading.
> + */
> +struct task_struct * good_sigevent(sigevent_t * event)
> +{
> +     struct task_struct *rtn = current->group_leader;
> +
> +     if ((event->sigev_notify & SIGEV_THREAD_ID ) &&
> +             (!(rtn = find_task_by_pid(event->sigev_notify_thread_id)) ||
> +              rtn->tgid != current->tgid ||
> +              (event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL))
> +             return NULL;
> +
> +     if (((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) &&
> +         ((event->sigev_signo <= 0) || (event->sigev_signo > SIGRTMAX)))
> +             return NULL;
> +
> +     return rtn;
> +}

And while we're at it we should badly beat up the person that wrote this
mess in the first time.  To be somewhat readable it should look like:

static struct task_struct *good_sigevent(sigevent_t *event)
{
        struct task_struct *task = current->group_leader;

        if ((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) {
                if (event->sigev_signo <= 0 || event->sigev_signo > SIGRTMAX)
                        return NULL;
        }

        if (event->sigev_notify & SIGEV_THREAD_ID) {
                if ((event->sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_SIGNAL)
                        return NULL;
                task = find_task_by_pid(event->sigev_notify_thread_id);
                if (!task || task->tgid != current->tgid)
                        return NULL;
        }

        return task;
}

And btw, looking at its currentl caller I see why we need the PF_EXITING
flag I recommended to remove easiler on, it even has a big comment that
we should copy & paste to aio.c aswell.  Still no idea why it's doing
the selectiv reference grabbing, though.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to