[Vortex] invalid write in __vortex_channel_common_rpy

[Francis Brosnan Blazquez]

Hi Dexter,

> > Hi Dexter,
> > 
> > Sorry for the delay. I've been out of the office. 
> > 
> > Thanks for reporting in any case!
> > 
> Hey, no probs. It's summer after all :)

;-)

> > Ok, I've been checking the code but it is not clear to me how the race
> > happens and how your patch fixes the issue. It would be very helpful to
> > know on which line happens the free (your trace do not include that) and
> > on which line happens invalid write.
> > 
> > Maybe you can post another valgrind trace but also including vortex
> > debug lines (where jump happens).
> > 
> Yes, we had some problems with the debug infos missing. Unfortunately
> I'm not on that project right now. We work on a project at work where we
> use vortex, and I'm not always on that project. So right now I don't
> really have the context to reproduce the issue, but I hope we can go
> back to it in the near future.

Ok. 

> > I've compared these portion of code with 1.1 series and are essentially
> > the same (only a couple of modifications to include global
> > notifications). 
> > 
> > Taking together all pieces it looks like the channel that was closed
> > previously, and was reused later by MessageTransportServer::response
> > causing the invalid write. 
> > 
> As far as I remember we were investigeting this also, but at the end we
> came to a conclusion that the mentioned patch could be the issue.

I see. To know where the free and the wrong access happens will be key
to know if we have a race due to mutex sync or because channel access
after finishing the reference...

> > Cheers!
> > 
> >> We're still using the old 1.0.17.b3739.g3739 version.
> > 
> > ...maybe you could consider switching to 1.1 series and see if the bug
> > still persists. It won't take you more effort than tracing why you get
> > this wrong ref. 
> > 
> We definitely have to do this sooner or later, I hope it'll be sooner :)

Great. Cheers!
-- 
Francis Brosnan Blazquez <francis at aspl.es>
ASPL