From: Philippe Antoine <pantoine@oisf.net>
Date: Sun, 24 Mar 2024 20:12:15 +0000 (+0100)
Subject: detect/parse: set limits for pcre2
X-Git-Tag: suricata-7.0.5~1
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=bcc65a7ffab48781cd90e4364d863553d6e20114;p=thirdparty%2Fsuricata.git

detect/parse: set limits for pcre2

Ticket: 6889

To avoid regexp dos with too much backtracking.
This is already done on pcre keyword, and pcrexform transform.
We use the same default limits for rules parsing.

(cherry picked from commit 316cc528f784c86339d05907a4d6084cbe4d44e6)
---

diff --git a/src/detect-parse.c b/src/detect-parse.c
index c3232b97da..5dee7e6bc2 100644
--- a/src/detect-parse.c
+++ b/src/detect-parse.c
@@ -2701,7 +2701,7 @@ int DetectParsePcreExec(DetectParseRegex *parse_regex, pcre2_match_data **match,
     *match = pcre2_match_data_create_from_pattern(parse_regex->regex, NULL);
     if (*match)
         return pcre2_match(parse_regex->regex, (PCRE2_SPTR8)str, strlen(str), options, start_offset,
-                *match, NULL);
+                *match, parse_regex->context);
     return -1;
 }
 
@@ -2761,8 +2761,16 @@ bool DetectSetupParseRegexesOpts(const char *parse_str, DetectParseRegex *detect
                 parse_str, en, errbuffer);
         return false;
     }
-    detect_parse->match = pcre2_match_data_create_from_pattern(detect_parse->regex, NULL);
 
+    detect_parse->context = pcre2_match_context_create(NULL);
+    if (detect_parse->context == NULL) {
+        SCLogError("pcre2 could not create match context");
+        pcre2_code_free(detect_parse->regex);
+        detect_parse->regex = NULL;
+        return false;
+    }
+    pcre2_set_match_limit(detect_parse->context, SC_MATCH_LIMIT_DEFAULT);
+    pcre2_set_recursion_limit(detect_parse->context, SC_MATCH_LIMIT_RECURSION_DEFAULT);
     DetectParseRegexAddToFreeList(detect_parse);
 
     return true;