Re: ExecRTCheckPerms() and many prunable partitions (checkAsUser)

Amit Langote <amitlangote09@gmail.com>

From: Amit Langote <amitlangote09@gmail.com>
To: Justin Pryzby <pryzby@telsasoft.com>
Cc: Alvaro Herrera <alvherre@alvh.no-ip.org>, Ian Lawrence Barwick <barwick@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, David Rowley <dgrowleyml@gmail.com>, Greg Stark <stark@mit.edu>, Julien Rouhaud <rjuju123@gmail.com>, pgsql-hackers@lists.postgresql.org
Date: 2022-12-12T06:23:22Z
Lists: pgsql-hackers

Attachments

On Sun, Dec 11, 2022 at 6:25 PM Amit Langote <amitlangote09@gmail.com> wrote:
> I've attached 0001 to remove those extraneous code blocks and add a
> comment mentioning that userid need not be recomputed.
>
> While staring at the build_simple_rel() bit mentioned above, I
> realized that this code fails to set userid correctly in the
> inheritance parent rels that are child relations of subquery parent
> relations, such as UNION ALL subqueries.  In that case, instead of
> copying the userid (= 0) of the parent rel, the child should look up
> its own RTEPermissionInfo, which should be there, and use the
> checkAsUser value from there.  I've attached 0002 to fix this hole.  I
> am not sure whether there's a way to add a test case for this in the
> core suite.

Ah, I realized we could just expand the test added by 553d2ec27 with a
wrapper view (to test checkAsUser functionality) and a UNION ALL query
over the view (to test this change).

I've done that in the attached updated patch, in which I've also
addressed Justin's comments.

-- 
Thanks, Amit Langote
EDB: http://www.enterprisedb.com

Commits

  1. Add a test case for a316a3bc

  2. Correctly set userid of subquery relations' child rels

  3. Fix buggy recursion in flatten_rtes_walker().

  4. Remove some dead code in selfuncs.c

  5. Update outdated comment in ApplyRetrieveRule

  6. Rework query relation permission checking

  7. Generalize ri_RootToPartitionMap to use for non-partition children

  8. Stop accessing checkAsUser via RTE in some cases

  9. Add 'missing_ok' argument to build_attrmap_by_name