From: Tom Lane <tgl@sss.pgh.pa.us>
Date: Fri, 2 Oct 2015 19:00:52 +0000 (-0400)
Subject: Add recursion depth protection to LIKE matching.
X-Git-Tag: REL9_0_23~13
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=b875ca09f3626e4002b5e70e00f99e4bc29c4d32;p=thirdparty%2Fpostgresql.git

Add recursion depth protection to LIKE matching.

Since MatchText() recurses, it could in principle be driven to stack
overflow, although quite a long pattern would be needed.
---

diff --git a/src/backend/utils/adt/like.c b/src/backend/utils/adt/like.c
index b338f451c3d..84e74e84574 100644
--- a/src/backend/utils/adt/like.c
+++ b/src/backend/utils/adt/like.c
@@ -20,6 +20,7 @@
 #include <ctype.h>
 
 #include "mb/pg_wchar.h"
+#include "miscadmin.h"
 #include "utils/builtins.h"
 
 
diff --git a/src/backend/utils/adt/like_match.c b/src/backend/utils/adt/like_match.c
index 4f762b85c33..0af0ddcf49d 100644
--- a/src/backend/utils/adt/like_match.c
+++ b/src/backend/utils/adt/like_match.c
@@ -82,6 +82,9 @@ MatchText(char *t, int tlen, char *p, int plen)
 	if (plen == 1 && *p == '%')
 		return LIKE_TRUE;
 
+	/* Since this function recurses, it could be driven to stack overflow */
+	check_stack_depth();
+
 	/*
 	 * In this loop, we advance by char when matching wildcards (and thus on
 	 * recursive entry to this function we are properly char-synced). On other