diff --git a/src/dns.c b/src/dns.c
index 1ef5e87..c4b2af0 100644
--- a/src/dns.c
+++ b/src/dns.c
@@ -1023,7 +1023,7 @@
 	if (dss->maxconn && (dss->maxconn <= dss->cur_conns))
 		return NULL;
 
-	ds = pool_alloc(dns_session_pool);
+	ds = pool_zalloc(dns_session_pool);
 	if (!ds)
 		return NULL;