From c9742dfbf4040931ff84e34b12db5d0e4e5499e0 Mon Sep 17 00:00:00 2001
From: Remi Gacogne <remi.gacogne@powerdns.com>
Date: Thu, 28 Apr 2016 10:59:27 +0200
Subject: [PATCH] Throw on negative label length in `DNSName::isPartOf()`

Found with American Fuzzy Lop and Address Sanitizer.
---
 pdns/dnsname.cc | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/pdns/dnsname.cc b/pdns/dnsname.cc
index 7111ff18d1..cfc4d4bebe 100644
--- a/pdns/dnsname.cc
+++ b/pdns/dnsname.cc
@@ -201,6 +201,9 @@ bool DNSName::isPartOf(const DNSName& parent) const
       }
       return true;
     }
+    if (*us < 0) {
+      throw std::out_of_range("negative label length in dnsname");
+    }
   }
   return false;
 }
-- 
2.47.2