From ada4c6055c06dd6d2032a67e98d64255b3cf6c6f Mon Sep 17 00:00:00 2001
From: millert <millert@openbsd.org>
Date: Sun, 21 Jun 2015 03:20:56 +0000
Subject: [PATCH] Just return if nmemb is 0.  Avoids a NULL dereference and is
 consistent with the behavior of the other libc sort functions. OK deraadt@

---
 lib/libc/stdlib/merge.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/libc/stdlib/merge.c b/lib/libc/stdlib/merge.c
index 43ef8b08e26..d60317ce082 100644
--- a/lib/libc/stdlib/merge.c
+++ b/lib/libc/stdlib/merge.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: merge.c,v 1.9 2011/03/06 00:55:38 deraadt Exp $ */
+/*	$OpenBSD: merge.c,v 1.10 2015/06/21 03:20:56 millert Exp $ */
 /*-
  * Copyright (c) 1992, 1993
  *	The Regents of the University of California.  All rights reserved.
@@ -101,6 +101,9 @@ mergesort(void *base, size_t nmemb, size_t size,
 		return (-1);
 	}
 
+	if (nmemb == 0)
+		return (0);
+
 	/*
 	 * XXX
 	 * Stupid subtraction for the Cray.
-- 
2.20.1