From: Otto Moerbeek <otto.moerbeek@open-xchange.com>
Date: Tue, 2 Jul 2024 10:22:29 +0000 (+0200)
Subject: Avoid upos underflowing in match loop
X-Git-Tag: rec-5.2.0-alpha1~203^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=09462bda7f8da4e59307e0d6a7446d499c1da34c;p=thirdparty%2Fpdns.git

Avoid upos underflowing in match loop
---

diff --git a/ext/yahttp/yahttp/router.cpp b/ext/yahttp/yahttp/router.cpp
index fdf23a45c5..5f6885a887 100644
--- a/ext/yahttp/yahttp/router.cpp
+++ b/ext/yahttp/yahttp/router.cpp
@@ -62,8 +62,15 @@ namespace YaHTTP {
           }
           nend = upos;
           params[pname] = funcptr::tie(nstart, nend);
-
-          upos--;
+          if (upos > 0) {
+            upos--;
+          }
+          else {
+            // If upos is zero, do not decrement it and then increment at bottom of loop, this disturbs Coverity.
+            // Only increment rpos and continue loop
+            rpos++;
+            continue;
+          }
         }
         else if (route[rpos] != requrl.path[upos]) {
           break;