Re: Fix race condition in pg_get_publication_tables with concurrent DROP TABLE

Hi,

On Wed, Apr 29, 2026 at 12:15 AM Bharath Rupireddy
<bharath(dot)rupireddyforpostgres(at)gmail(dot)com> wrote:
>
> Fixed. Please find the attached v5 patch.
>
> The fix is needed only for PG16 and later, not PG15 or PG14. The bug
> was introduced by b7ae03953690 [1] in PG16, which added a table_open()
> call in pg_get_publication_tables(). PG15 and earlier only use
> get_rel_namespace() and syscache lookups, both of which gracefully
> handle dropped relations (returning InvalidOid/false rather than
> erroring).
>
> I verified the bug and the fix on all affected branches. Please find
> the attached version-specific patches for backpatching. Thank you!
>
> [1] b7ae03953690 - Ignore dropped and generated columns from the column list

Please find the attached v6 patch, which fixes a test failure on
FreeBSD. This variant of the build forces parallel query via
debug_parallel_query=regress, causing the pg_get_publication_tables
injection point to fire in parallel workers as well. I disabled forced
parallel query for this test case.

Thank you!

--
Bharath Rupireddy
Amazon Web Services: https://aws.amazon.com