Re: allow granting CLUSTER, REFRESH MATERIALIZED VIEW, and REINDEX

On Thu, Dec 15, 2022 at 10:10:43AM -0800, Jeff Davis wrote:
> The proposal to skip privilege checks for partitions would be
> consistent with INSERT, SELECT, REINDEX that flow through to the
> underlying partitions regardless of permissions/ownership (and even
> RLS). It would be very minor behavior change on 15 for this weird case
> of superuser-owned partitions, but I doubt anyone would be relying on
> that.

I've attached a work-in-progress patch that aims to accomplish this.
Instead of skipping the privilege checks, I added logic to trawl through
pg_inherits and pg_class to check whether the user has privileges for the
partitioned table or for the main relation of a TOAST table.  This means
that MAINTAIN on a partitioned table is enough to execute maintenance
commands on all the partitions, and MAINTAIN on a main relation is enough
to execute maintenance commands on its TOAST table.  Also, the maintenance
commands that flow through to the partitions or the TOAST table should no
longer error due to permissions when the user only has MAINTAIN on the
paritioned table or main relation.

--
Nathan Bossart
Amazon Web Services: https://aws.amazon.com

+cluster_is_permitted_for_relation(Oid relid, Oid userid)
+{
+       return pg_class_aclcheck(relid, userid, ACL_MAINTAIN) == ACLCHECK_OK ||