Re: [PATCH -mm][AIO] Fix AIO completion signal notification possible ref leak

Sébastien Dugué
2007-02-06T08:33:08Z

On Mon, 5 Feb 2007 20:13:35 +0300 Oleg Nesterov <oleg@tv-sign.ru> wrote:

> On 02/05, S?bastien Dugu? wrote:
> >
> > Make sure we only accept valid sigev_notify values in aio_setup_sigevent(),
> > namely SIGEV_NONE, SIGEV_THREAD_ID or SIGEV_SIGNAL.
>
> I think this is correct, but I have another concern (most probably I just
> confused looking at non-applied patch), could you re-check?
>
> > @@ -959,6 +959,10 @@ static long aio_setup_sigevent(struct ai
> > if (event.sigev_notify == SIGEV_NONE)
> > return 0;
> >
> > + if (event.sigev_notify != SIGEV_SIGNAL &&
> > + event.sigev_notify != SIGEV_THREAD_ID)
> > + return -EINVAL;
> > +
> > notify->notify = event.sigev_notify;
> > notify->signo = event.sigev_signo;
> > notify->value = event.sigev_value;
>
> Ok. But what if sigevent_find_task() fails after that? Doesn't this mean
> that really_put_req() will do put_task_struct(NULL) ?
>

Argh, right, a patch to fix that and a couple of other corner cases to
follow soon.

Thanks Oleg for looking through this.

Sébastien.