Add check for syscache lookup failure in update_relispartition().

tglsfdc · tglsfdc · commit 62148c3520b5 · 2019-05-05T12:44:32.000-04:00
Omitted in commit 05b38c7 (though it looks like the original blame belongs to 9e9befa). A failure is admittedly unlikely, but if it did happen, SIGSEGV is not the approved method of reporting it. Per Coverity. Back-patch to v11 where the broken code originated.
diff --git a/src/backend/commands/indexcmds.c b/src/backend/commands/indexcmds.c
@@ -3451,10 +3451,11 @@ update_relispartition(Oid relationId, bool newval)
 
 	classRel = table_open(RelationRelationId, RowExclusiveLock);
 	tup = SearchSysCacheCopy1(RELOID, ObjectIdGetDatum(relationId));
+	if (!HeapTupleIsValid(tup))
+		elog(ERROR, "cache lookup failed for relation %u", relationId);
 	Assert(((Form_pg_class) GETSTRUCT(tup))->relispartition != newval);
 	((Form_pg_class) GETSTRUCT(tup))->relispartition = newval;
 	CatalogTupleUpdate(classRel, &tup->t_self, tup);
 	heap_freetuple(tup);
-
 	table_close(classRel, RowExclusiveLock);
 }
