From 3bdeed02505c9bbacb3b64a97ddcb1de967153b7 Mon Sep 17 00:00:00 2001
From: Willem Toorop <willem@nlnetlabs.nl>
Date: Thu, 27 Apr 2017 00:25:20 +0200
Subject: [PATCH] bugfix #1257: Free after reallocing to 0 size

Thanks Stephan Zeisberg
---
 str2host.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/str2host.c b/str2host.c
index b274b17..f2a317b 100644
--- a/str2host.c
+++ b/str2host.c
@@ -1525,8 +1525,10 @@ ldns_str2rdf_long_str(ldns_rdf **rd, const char *str)
 	if (! str) {
 		return LDNS_STATUS_SYNTAX_BAD_ESCAPE;
 	}
-	length = (size_t)(dp - data);
-
+	if (!(length = (size_t)(dp - data))) {
+		LDNS_FREE(data);
+		return LDNS_STATUS_SYNTAX_EMPTY;
+	}
 	/* Lose the overmeasure */
 	data = LDNS_XREALLOC(dp = data, uint8_t, length);
 	if (! data) {
-- 
2.9.5