It's bad idea to leave critical section with error object freed, but
s->error still set, this theoretically may lead to use-after-free
crash. Let's avoid it.
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru> Reviewed-by: Fabiano Rosas <farosas@suse.de> Reviewed-by: Peter Xu <peterx@redhat.com> Signed-off-by: Fabiano Rosas <farosas@suse.de>