From 71a851e9d74e1c3d74428700eca1f11437600bcd Mon Sep 17 00:00:00 2001 From: Ashutosh Bapat Date: Wed, 15 Apr 2026 17:38:25 +0530 Subject: [PATCH v20260415 2/3] Check for stack overflow when rewriting graph queries. generate_queries_for_path_pattern_recurse() and generate_setop_from_pathqueries() are recursive functions. For a property graph with hundreds of tables, a graph pattern with a handful element patterns can cause stack overflow. Fix it by calling check_stack_depth() at the beginning of these functions. Reported-by: Satyanarayana Narlapuram Author: Satyanarayana Narlapuram Reviewed-by: Ashutosh Bapat Discussion: https://www.postgresql.org/message-id/CAHg+QDfgK0xddH8f3eAb+UVn7sBDOnv8RvM6OkP4HtHAt6aD7w@mail.gmail.com --- src/backend/rewrite/rewriteGraphTable.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/src/backend/rewrite/rewriteGraphTable.c b/src/backend/rewrite/rewriteGraphTable.c index 2c3199d3230..429ef1cf1f4 100644 --- a/src/backend/rewrite/rewriteGraphTable.c +++ b/src/backend/rewrite/rewriteGraphTable.c @@ -17,6 +17,7 @@ #include "access/sysattr.h" #include "access/table.h" #include "access/htup_details.h" +#include "miscadmin.h" #include "catalog/pg_operator.h" #include "catalog/pg_propgraph_element.h" #include "catalog/pg_propgraph_element_label.h" @@ -361,6 +362,9 @@ generate_queries_for_path_pattern_recurse(RangeTblEntry *rte, List *pathqueries, { List *path_elems = list_nth_node(List, path_elem_lists, elempos); + /* Guard against stack overflow due to complex path patterns. */ + check_stack_depth(); + foreach_ptr(struct path_element, pe, path_elems) { /* Update current path being built with current element. */ @@ -698,6 +702,9 @@ generate_setop_from_pathqueries(List *pathqueries, List **rtable, List **targetl List *rtargetlist; ParseNamespaceItem *pni; + /* Guard against stack overflow due to many path queries. */ + check_stack_depth(); + /* Recursion termination condition. */ if (list_length(pathqueries) == 0) { -- 2.34.1