From e39e6974297e7031bd2f9fc2ecc0abb94b3caa87 Mon Sep 17 00:00:00 2001
From: Martin Willi <martin@revosec.ch>
Date: Tue, 24 Jul 2012 12:20:32 +0200
Subject: [PATCH] Check if subset calculation actually yields a TS in Unity
 narrowing

---
 src/libcharon/plugins/unity/unity_narrow.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/libcharon/plugins/unity/unity_narrow.c b/src/libcharon/plugins/unity/unity_narrow.c
index dada26dc6..a5fcfabc7 100644
--- a/src/libcharon/plugins/unity/unity_narrow.c
+++ b/src/libcharon/plugins/unity/unity_narrow.c
@@ -53,7 +53,11 @@ METHOD(listener_t, narrow, bool,
 			{	/* got one, replace original TS */
 				remote->remove_first(remote, (void**)&orig);
 			}
-			remote->insert_last(remote, orig->get_subset(orig, current));
+			current = orig->get_subset(orig, current);
+			if (current)
+			{
+				remote->insert_last(remote, current);
+			}
 		}
 		enumerator->destroy(enumerator);
 		if (orig)