Horton

Re: Running the fdw test from the terminal crashes into the core-dump

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@alvh.no-ip.org>
Cc: Alena Rybakina <a.rybakina@postgrespro.ru>, Pgsql Hackers <pgsql-hackers@postgresql.org>, Amit Langote <amitlangote09@gmail.com>
Date: 2024-02-20T19:48:01Z
Lists: pgsql-hackers 
Alvaro Herrera <alvherre@alvh.no-ip.org> writes:
> The real problem is that a MERGE ... DO NOTHING action reports that no
> permissions need to be checked on the target relation, which is not a
> problem when there are other actions in the MERGE command since they add
> privs to check.  When DO NOTHING is the only action, the added assert in
> a61b1f748 is triggered.

> So, this means we can fix this by simply requiring ACL_SELECT privileges
> on a DO NOTHING action.  We don't need to request specific privileges on
> any particular column (perminfo->selectedCols continues to be the empty
> set) -- which means that any role that has privileges on *any* column
> would get a pass.  If you're doing MERGE with any other action besides
> DO NOTHING, you already have privileges on at least some column, so
> adding ACL_SELECT breaks nothing.

LGTM.

			regards, tom lane

Commits

  1. Revise MERGE documentation

  2. MERGE ... DO NOTHING: require SELECT privileges

  3. Rework query relation permission checking