From 61deba379eee0674d8aae40f5e6c84bdd724e820 Mon Sep 17 00:00:00 2001
From: Luke Dashjr <luke-jr+git@utopios.org>
Date: Thu, 1 Dec 2016 23:30:06 +0000
Subject: [PATCH] Avoid memcpy with potentially NULL pointer if scriptsz is
 zero

---
 blkmaker.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/blkmaker.c b/blkmaker.c
index 96abc05..228f91b 100644
--- a/blkmaker.c
+++ b/blkmaker.c
@@ -101,8 +101,10 @@ uint64_t blkmk_init_generation3(blktemplate_t * const tmpl, const void * const s
 	my_htole64(&data[off], tmpl->cbvalue);
 	off += 8;
 	data[off++] = scriptsz;
-	memcpy(&data[off], script, scriptsz);
-	off += scriptsz;
+	if (scriptsz) {
+		memcpy(&data[off], script, scriptsz);
+		off += scriptsz;
+	}
 	memset(&data[off], 0, 4);  // lock time
 	off += 4;