postgres.git / summary / log / commit / refs

commit    2ff289d03939498a656a0c6cf2da08623f8357b4
Author:   Peter Eisentraut <peter@eisentraut.org>
Date:     Fri Apr 24 06:18:21 2026 +0000

    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.
    
    Author: Satyanarayana Narlapuram <satyanarlapuram@gmail.com>
    Reviewed-by: Ashutosh Bapat <ashutosh.bapat.oss@gmail.com>
    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 3519ea3beae..3aac29f5840 100644
--- a/src/backend/rewrite/rewriteGraphTable.c
+++ b/src/backend/rewrite/rewriteGraphTable.c
@@ -23,6 +23,7 @@
 #include "catalog/pg_propgraph_label.h"
 #include "catalog/pg_propgraph_label_property.h"
 #include "catalog/pg_propgraph_property.h"
+#include "miscadmin.h"
 #include "nodes/makefuncs.h"
 #include "nodes/nodeFuncs.h"
 #include "optimizer/optimizer.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)
 	{


[parent: 863c4b827d92]