talloc: talloc_set_memlimit causes all reallocs to fail when used on pools. talloc_set_memlimit not enforced correctly on pools.

[Jeremy Allison]

On Tue, Oct 20, 2020 at 01:42:00PM -0500, Arran Cudbard-Bell wrote:
> 
> 
> > On Oct 20, 2020, at 1:33 PM, Jeremy Allison <jra at samba.org> wrote:
> > 
> > On Tue, Oct 20, 2020 at 01:03:14PM -0500, Arran Cudbard-Bell wrote:
> >> 
> >> Then there's another issue with object_count ending
> >> up off by one, which means talloc_free_children doesn't
> >> actually return memory to the pool, and that messes up
> >> some of the other tests I'm adding.  Just tracking down
> >> when and why this happens now.... It might have been a
> >> pre-existing issue and not related to this patch, I'm just
> >> seeing it because of using talloc_free_children to reset
> >> the pool between some tests.
> 
> Apologies, there was a steal I didn't spot in the tests.
> One of the chunks was moved out of the pool into the root ctx.
> 
> Explicitly freeing the chunk or stealing it back into the pool
> means talloc_free_children works as expected.

FYI, once you've gotten everything working can you
send your test cases to me so I can add them into
the regression test suite for talloc ?

Then we'll add a new bug in bugzilla, update the minor library
version number and create a gitlab MR.