Re: [patch 02/20] posix-timers: Ensure timer ID search-loop limit is valid

From: Thomas Gleixner
Date: Tue May 09 2023 - 08:38:56 EST


On Tue, May 09 2023 at 11:42, Frederic Weisbecker wrote:
> On Sat, May 06, 2023 at 01:36:22AM +0200, Thomas Gleixner wrote:
>> Unless you think about the theoretical case of an unlimited number of
>> threads sharing the signal_struct which all concurrently try to allocate
>> a timer id and then releasing it immediately again (to avoid resource
>> limit exhaustion). Theoretically possible, but is this a real concern
>> with a timer ID space of 2G?
>
> I didn't go that far actually, it was just me misunderstanding that loop and
> especially the (id =~start) part. Now I got it.
>
> I guess the for statement can just be:
>
> for (; start != id; id++)

My brain based compiler complains about uninitialized usage of @id. I'm
pretty sure it's rightfully complaining and a real compiler would agree,
no?

Thanks,

tglx