commit 8a03ccbb77f52ec4b55062eeedddb8daec1a33e4
Author: Florian Weimer <fweimer@redhat.com>
Date:   Mon May 2 16:04:32 2016 +0200

    hesiod: Avoid heap overflow in get_txt_records [BZ #20031]

Index: b/hesiod/hesiod.c
===================================================================
--- a/hesiod/hesiod.c
+++ b/hesiod/hesiod.c
@@ -421,7 +421,7 @@ get_txt_records(struct hesiod_p *ctx, in
 		cp += INT16SZ + INT32SZ;	/* skip the ttl, too */
 		rr.dlen = ns_get16(cp);
 		cp += INT16SZ;
-		if (cp + rr.dlen > eom) {
+		if (rr.dlen == 0 || cp + rr.dlen > eom) {
 			__set_errno(EMSGSIZE);
 			goto cleanup;
 		}