Re: pg_get_functiondef forgets about most GUC_LIST_INPUT GUCs

On Thu, Mar 15, 2018 at 06:48:36PM +0900, Kyotaro HORIGUCHI wrote:
> So, we should reject to define function in the case. We don't
> accept the GUC element if it is just a placeholder.
> 
> The attached is a rush work of my idea. Diff for pg_proc.h is too
> large so it is separated and gziped.
> 
> It adds a column named "proconfigislist" of array(bool) in
> pg_proc. When defined function has set clauses, it generates a
> proconfig-is-list-or-not array and set. It ends with error if
> required module is not loaded yet. Perhaps
> GetConfigOptionFlags(,false) shouldn't return 0 if no option
> element is found but I don't amend it for now.

I think your approach has a vulnerability too. I believe that a
non GUC_LIST_INPUT extension GUC which was used to create a function may
become GUC_LIST_INPUT variable. If I'm not mistaken nothing stops from
that. In this case values in proconfigislist won't be valide anymore.

-- 
Arthur Zakirov
Postgres Professional: http://www.postgrespro.com
Russian Postgres Company