selftests: net: kill smcrouted in the cleanup logic in amt.sh

BugLink: https://bugs.launchpad.net/bugs/2073603

[ Upstream commit cc563e749810f5636451d4b833fbd689899ecdb9 ]

The amt.sh requires smcrouted for multicasting routing.
So, it starts smcrouted before forwarding tests.
It must be stopped after all tests, but it isn't.

To fix this issue, it kills smcrouted in the cleanup logic.

Fixes: c08e8baea7 ("selftests: add amt interface selftest script")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Portia Stephens <portia.stephens@canonical.com>
Signed-off-by: Roxana Nicolescu <roxana.nicolescu@canonical.com>

tools/testing/selftests/net/amt.sh

@@ -77,6 +77,7 @@ readonly LISTENER=$(mktemp -u listener-XXXXXXXX)
 readonly GATEWAY=$(mktemp -u gateway-XXXXXXXX)
 readonly RELAY=$(mktemp -u relay-XXXXXXXX)
 readonly SOURCE=$(mktemp -u source-XXXXXXXX)
+readonly SMCROUTEDIR="$(mktemp -d)"
 ERR=4
 err=0
 
@@ -85,6 +86,11 @@ exit_cleanup()
 	for ns in "$@"; do
 		ip netns delete "${ns}" 2>/dev/null || true
 	done
+	if [ -f "$SMCROUTEDIR/amt.pid" ]; then
+		smcpid=$(< $SMCROUTEDIR/amt.pid)
+		kill $smcpid
+	fi
+	rm -rf $SMCROUTEDIR
 
 	exit $ERR
 }
@@ -167,7 +173,7 @@ setup_iptables()
 
 setup_mcast_routing()
 {
-	ip netns exec "${RELAY}" smcrouted
+	ip netns exec "${RELAY}" smcrouted -P $SMCROUTEDIR/amt.pid
 	ip netns exec "${RELAY}" smcroutectl a relay_src \
 		172.17.0.2 239.0.0.1 amtr
 	ip netns exec "${RELAY}" smcroutectl a relay_src \