Re: Kernel patches enabling better POSIX AIO (Was Re: [3/4] kevent: AIO, aio_sendfile)

Nicholas Miell
2006-08-15T02:07:33Z

On Mon, 2006-08-14 at 09:38 -0700, Ulrich Drepper wrote:
> Suparna Bhattacharya wrote:
> > Is there a (remote) possibility that the thread could have died and its
> > pid got reused by a new thread in another process ? Or is there a mechanism
> > that prevents such a possibility from arising (not just in NPTL library,
> > but at the kernel level) ?
>
> The UID/GID won't help you with dying processes. What if the same user
> creates a process with the same PID? That process will not expect the
> notification and mustn't receive it. If you cannot detect whether the
> issuing process died you have problems which cannot be solved with a
> uid/gid pair.
>
>

Eric W. Biederman sent a series of patches that introduced a struct
task_ref specifically to solve this sort of problem on January 28 of
this year, but I don't think it went anywhere.

--
Nicholas Miell <nmiell@comcast.net>