From faf8963c9ac74a263cc4e6fa1631425d7bb1cad9 Mon Sep 17 00:00:00 2001
From: Steven Allen <steven@stebalien.com>
Date: Thu, 18 Oct 2018 10:35:11 +0100
Subject: [PATCH] fix zone validator

(bug caught by fuzzer)
---
 transcoders.go | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/transcoders.go b/transcoders.go
index 86ce200..b5408f0 100644
--- a/transcoders.go
+++ b/transcoders.go
@@ -73,6 +73,9 @@ func ip6zoneBtS(b []byte) (string, error) {
 }
 
 func ip6zoneVal(b []byte) error {
+	if len(b) == 0 {
+		return fmt.Errorf("invalid length (should be > 0)")
+	}
 	// Not supported as this would break multiaddrs.
 	if bytes.IndexByte(b, '/') >= 0 {
 		return fmt.Errorf("IPv6 zone ID contains '/': %s", string(b))