pgsql: Ensure ExecutorCheckPerms_hook is called from RI fast path - Mailing list pgsql-committers

From Amit Langote
Subject pgsql: Ensure ExecutorCheckPerms_hook is called from RI fast path
Date
Msg-id E1x9gkw-0000000137A-2Fn1@gemulon.postgresql.org
Whole thread
List pgsql-committers
Ensure ExecutorCheckPerms_hook is called from RI fast path

The fast path's ri_CheckPermissions() called ExecCheckOneRelPerms()
directly, so ExecutorCheckPerms_hook never saw the referenced-table
access that the SPI path's query exposed to it via ExecutorStart().
Modules such as sepgsql that rely on this hook therefore lost control
over FK checks against referenced tables that go through the fast
path.

So, build a one-entry range table and permission-info list and call
ExecCheckPermissions().  The hook now sees the same relation and
requiredPerms as before, once per check that goes through the fast
path.  This also drops the shortcut that skipped the column-level
check when table-level privileges sufficed, since the hook must run
regardless.  While at it, drop the explicit frees in the old code,
because both callers run ri_CheckPermissions() in a per-tuple context
that is reset after each check, so they were redundant.

Reported-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/20260705210533.ee.noahmisch%40microsoft.com
Backpatch-through: 19

Branch
------
REL_19_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/5aeb36f3273c768831284082f85b63066e84f16d

Modified Files
--------------
src/backend/utils/adt/ri_triggers.c | 30 +++++++++++++++---------------
1 file changed, 15 insertions(+), 15 deletions(-)


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