From 7b91011d6edf2febbce28f3d73d149a7f0b81843 Mon Sep 17 00:00:00 2001
From: Tobias Brunner <tobias@strongswan.org>
Date: Thu, 28 Mar 2013 14:12:53 +0100
Subject: [PATCH] Allow memstr() to be called with NULL arguments

---
 src/libstrongswan/utils/utils.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/libstrongswan/utils/utils.c b/src/libstrongswan/utils/utils.c
index ba32720ea..aa59f4a4d 100644
--- a/src/libstrongswan/utils/utils.c
+++ b/src/libstrongswan/utils/utils.c
@@ -102,7 +102,12 @@ void memwipe_noinline(void *ptr, size_t n)
 void *memstr(const void *haystack, const char *needle, size_t n)
 {
 	unsigned const char *pos = haystack;
-	size_t l = strlen(needle);
+	size_t l;
+
+	if (!haystack || !needle || (l = strlen(needle)) == 0)
+	{
+		return NULL;
+	}
 	for (; n >= l; ++pos, --n)
 	{
 		if (memeq(pos, needle, l))