Re: Clarification on Role Access Rights to Table Indexes

Jeff Davis <pgsql@j-davis.com>

From: Jeff Davis <pgsql@j-davis.com>

To: Nathan Bossart <nathandbossart@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>

Cc: Ayush Vatsa <ayushvatsa1810@gmail.com>, Robert Haas <robertmhaas@gmail.com>, "David G. Johnston" <david.g.johnston@gmail.com>, PostgreSQL Hackers <pgsql-hackers@postgresql.org>

Date: 2025-10-09T03:28:01Z

Lists: pgsql-hackers, pgsql-general

On Wed, 2025-10-08 at 20:06 -0700, Jeff Davis wrote:
> On Wed, 2025-09-24 at 11:52 -0500, Nathan Bossart wrote:
> > On Wed, Sep 24, 2025 at 12:13:34PM -0400, Tom Lane wrote:
> > > Nathan Bossart <nathandbossart@gmail.com> writes:
> > > > * RangeVarCallbackForReindexIndex() was checking privileges on
> > > > the table
> > > > before locking it, so I reversed it in 0002.
> > > 
> > > Don't we do that intentionally, to make sure someone can't cause
> > > DOS
> > > on a table they have no privileges on?
> > 
> > Ah, right.  I switched it back in v4.
> 
> v4-0001 looks good to me.

Actually, now I'm unsure. v4-0001 is taking a lock on the table before
checking privileges, whereas v4-0002 is going to some effort to avoid
that. Is that because the latter is taking a ShareLock?

Regards,
	Jeff Davis

Commits

Fix privilege checks for pg_prewarm() on indexes.
- fae0ce5e318e 16.11 landed
- f146eb45cb1a 14.20 landed
- a0551bc5734b 17.7 landed
- 6c03ae8d6e81 15.15 landed
- 3ccf8e9ac96e 18.1 landed
- 208927e65692 19 (unreleased) landed
- 19a64f5676bb 13.23 landed
Fix lookup code for REINDEX INDEX.
- 079480dc2022 19 (unreleased) landed
Fix redefinition of typedef RangeVar.
- 15d7dded0e93 18.1 landed
Fix lookups in pg_{clear,restore}_{attribute,relation}_stats().
- c8af5019bee5 18.1 landed
- 688dc6299a5b 19 (unreleased) landed
dblink: Avoid locking relation before privilege check.
- c9b299f6df98 19 (unreleased) landed