Merge branch 'net-bridge-add-support-for-host-l2-mdb-entries'

Joachim Wiberg says:

====================
net: bridge: add support for host l2 mdb entries

Fix to an obvious omissions for layer-2 host mdb entries, this v2 adds
the missing selftest and some minor style fixes.

Note: this patch revealed some worrying problems in how the bridge
      forwards unknown BUM traffic and also how unknown multicast is
      forwarded when a IP multicast router is known, which a another
      (RFC) patch series intend to address.  That series will build
      on this selftest, hence the name of the test.

v2:
  - Add braces to other if/else clauses (Jakub)
  - Add selftest to verify add/del of mac/ipv4/ipv6 mdb entries (Jakub)
====================

Link: https://lore.kernel.org/r/20220411084054.298807-1-troglobit@gmail.comSigned-off-by: Paolo Abeni <pabeni@redhat.com>

net/bridge/br_mdb.c

@@ -251,14 +251,16 @@ static int __mdb_fill_info(struct sk_buff *skb,
 	__mdb_entry_fill_flags(&e, flags);
 	e.ifindex = ifindex;
 	e.vid = mp->addr.vid;
-	if (mp->addr.proto == htons(ETH_P_IP))
+	if (mp->addr.proto == htons(ETH_P_IP)) {
 		e.addr.u.ip4 = mp->addr.dst.ip4;
 #if IS_ENABLED(CONFIG_IPV6)
-	else if (mp->addr.proto == htons(ETH_P_IPV6))
+	} else if (mp->addr.proto == htons(ETH_P_IPV6)) {
 		e.addr.u.ip6 = mp->addr.dst.ip6;
 #endif
-	else
+	} else {
 		ether_addr_copy(e.addr.u.mac_addr, mp->addr.dst.mac_addr);
+		e.state = MDB_PG_FLAGS_PERMANENT;
+	}
 	e.addr.proto = mp->addr.proto;
 	nest_ent = nla_nest_start_noflag(skb,
 					 MDBA_MDB_ENTRY_INFO);
@@ -873,8 +875,8 @@ static int br_mdb_add_group(struct net_bridge *br, struct net_bridge_port *port,
 		return -EINVAL;
 
 	/* host join errors which can happen before creating the group */
-	if (!port) {
-		/* don't allow any flags for host-joined groups */
+	if (!port && !br_group_is_l2(&group)) {
+		/* don't allow any flags for host-joined IP groups */
 		if (entry->state) {
 			NL_SET_ERR_MSG_MOD(extack, "Flags are not allowed for host groups");
 			return -EINVAL;

tools/testing/selftests/net/forwarding/Makefile

@@ -2,6 +2,7 @@
 
 TEST_PROGS = bridge_igmp.sh \
 	bridge_locked_port.sh \
+	bridge_mdb.sh \
 	bridge_port_isolation.sh \
 	bridge_sticky_fdb.sh \
 	bridge_vlan_aware.sh \

tools/testing/selftests/net/forwarding/bridge_mdb.sh

+#!/bin/bash
+# SPDX-License-Identifier: GPL-2.0
+#
+# Verify that adding host mdb entries work as intended for all types of
+# multicast filters: ipv4, ipv6, and mac
+
+ALL_TESTS="mdb_add_del_test"
+NUM_NETIFS=2
+
+TEST_GROUP_IP4="225.1.2.3"
+TEST_GROUP_IP6="ff02::42"
+TEST_GROUP_MAC="01:00:01:c0:ff:ee"
+
+source lib.sh
+
+h1_create()
+{
+	simple_if_init $h1 192.0.2.1/24 2001:db8:1::1/64
+}
+
+h1_destroy()
+{
+	simple_if_fini $h1 192.0.2.1/24 2001:db8:1::1/64
+}
+
+switch_create()
+{
+	# Enable multicast filtering
+	ip link add dev br0 type bridge mcast_snooping 1
+
+	ip link set dev $swp1 master br0
+
+	ip link set dev br0 up
+	ip link set dev $swp1 up
+}
+
+switch_destroy()
+{
+	ip link set dev $swp1 down
+	ip link del dev br0
+}
+
+setup_prepare()
+{
+	h1=${NETIFS[p1]}
+	swp1=${NETIFS[p2]}
+
+	vrf_prepare
+
+	h1_create
+	switch_create
+}
+
+cleanup()
+{
+	pre_cleanup
+
+	switch_destroy
+	h1_destroy
+
+	vrf_cleanup
+}
+
+do_mdb_add_del()
+{
+	local group=$1
+	local flag=$2
+
+	RET=0
+	bridge mdb add dev br0 port br0 grp $group $flag 2>/dev/null
+	check_err $? "Failed adding $group to br0, port br0"
+
+	if [ -z "$flag" ]; then
+	    flag="temp"
+	fi
+
+	bridge mdb show dev br0 | grep $group | grep -q $flag 2>/dev/null
+	check_err $? "$group not added with $flag flag"
+
+	bridge mdb del dev br0 port br0 grp $group 2>/dev/null
+	check_err $? "Failed deleting $group from br0, port br0"
+
+	bridge mdb show dev br0 | grep -q $group >/dev/null
+	check_err_fail 1 $? "$group still in mdb after delete"
+
+	log_test "MDB add/del group $group to bridge port br0"
+}
+
+mdb_add_del_test()
+{
+	do_mdb_add_del $TEST_GROUP_MAC permanent
+	do_mdb_add_del $TEST_GROUP_IP4
+	do_mdb_add_del $TEST_GROUP_IP6
+}
+
+trap cleanup EXIT
+
+setup_prepare
+setup_wait
+
+tests_run
+
+exit $EXIT_STATUS