filter: fix segfault if the Filter clause is unused

This patch fixes a segfault when conntrackd -k is invoked for an
instance of conntrackd with no use of the Filter clause.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/src/run.c b/src/run.c
index b7da18c..34d20b0 100644
--- a/src/run.c
+++ b/src/run.c
@@ -40,7 +40,8 @@ void killer(int foo)
 	nfct_close(STATE(event));
 	nfct_close(STATE(request));
 
-	ct_filter_destroy(STATE(us_filter));
+	if (STATE(us_filter))
+		ct_filter_destroy(STATE(us_filter));
 	local_server_destroy(&STATE(local));
 	STATE(mode)->kill();