From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Tue, 26 May 2026 15:58:25 +0000 (-0400)
Subject: Add stack depth check to QueueFKConstraintValidation().
X-Git-Tag: REL_19_BETA1~48
X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=61ea5cc6a61ff9eb8b3d7b055e507a726e5856c7;p=thirdparty%2Fpostgresql.git

Add stack depth check to QueueFKConstraintValidation().

QueueFKConstraintValidation() recurses through the partition hierarchy
to queue child constraint validations and to mark child rows as
validated.  With a sufficiently deep partition tree, this can result
in a stack-overflow crash.  Defend against that as we do elsewhere.

Bug: #19482
Reported-by: Alexander Lakhin <exclusion@gmail.com>
Author: Ayush Tiwari <ayushtiwari.slg01@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Discussion: https://postgr.es/m/19482-4cc37cbf52d55235@postgresql.org
Backpatch-through: 18
---

diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c
index 1e0bacf85fc..a1845240a98 100644
--- a/src/backend/commands/tablecmds.c
+++ b/src/backend/commands/tablecmds.c
@@ -13281,6 +13281,9 @@ QueueFKConstraintValidation(List **wqueue, Relation conrel, Relation fkrel,
 	HeapTuple	copyTuple;
 	Form_pg_constraint copy_con;
 
+	/* since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	con = (Form_pg_constraint) GETSTRUCT(contuple);
 	Assert(con->contype == CONSTRAINT_FOREIGN);
 	Assert(!con->convalidated);