[lttng-dev] [PATCH lttng-ust] Fix: fd of an elf object must be registered to the fd tracker

[Jonathan Rajotte-Julien]

On Fri, Nov 10, 2017 at 02:02:07PM +0000, Mathieu Desnoyers wrote:
> > @@ -312,9 +321,15 @@ error:
> > 	if (elf) {
> > 		free(elf->ehdr);
> > 		if (elf->fd >= 0) {
> > -			if (close(elf->fd)) {
> > +			lttng_ust_lock_fd_tracker();
> > +			ret = close(elf->fd);
> > +			if (!ret) {
> > +				lttng_ust_delete_fd_from_tracker(elf->fd);
> > +			} else {
> > +				PERROR("close");
> > 				abort();
> > 			}
> > +			lttng_ust_lock_fd_tracker();
> 
> This appears to be a double-lock.

I was testing you... more seriously good catch.

> 
> How did you test this code path ?

I did not test the error path. Will be more careful in the future.

v2 simplify all of this by using lttng_ust_elf_destroy directly.

Cheers