From 7300cde3749f831733964106280697197184984c Mon Sep 17 00:00:00 2001
From: dmiller <dmiller@e0a8ed71-7df4-0310-8962-fdc924857419>
Date: Mon, 4 Jan 2016 21:44:47 +0000
Subject: [PATCH] Avoid segfault with vasprintf("%s", NULL).
 http://seclists.org/nmap-dev/2016/q1/4

---
 nbase/snprintf.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/nbase/snprintf.c b/nbase/snprintf.c
index a948d4f0a..f1c10a316 100644
--- a/nbase/snprintf.c
+++ b/nbase/snprintf.c
@@ -242,6 +242,8 @@ append_string (struct state *state,
                int prec,
                int flags)
 {
+  if(!arg)
+    arg = (unsigned char *) "(nall)";
   if(prec != -1)
     width -= prec;
   else