From d7bae09fa008c6c9a489580db0a5a12063b97f97 Mon Sep 17 00:00:00 2001 From: Nikolay Aleksandrov Date: Mon, 29 Jul 2019 12:28:41 +0300 Subject: [PATCH] net: bridge: delete local fdb on device init failure On initialization failure we have to delete the local fdb which was inserted due to the default pvid creation. This problem has been present since the inception of default_pvid. Note that currently there are 2 cases: 1) in br_dev_init() when br_multicast_init() fails 2) if register_netdevice() fails after calling ndo_init() This patch takes care of both since br_vlan_flush() is called on both occasions. Also the new fdb delete would be a no-op on normal bridge device destruction since the local fdb would've been already flushed by br_dev_delete(). This is not an issue for ports since nbp_vlan_init() is called last when adding a port thus nothing can fail after it. Reported-by: syzbot+88533dc8b582309bf3ee@syzkaller.appspotmail.com Fixes: 5be5a2df40f0 ("bridge: Add filtering support for default_pvid") Signed-off-by: Nikolay Aleksandrov Signed-off-by: David S. Miller --- net/bridge/br_vlan.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c index 021cc9f66804..a544e161c7fa 100644 --- a/net/bridge/br_vlan.c +++ b/net/bridge/br_vlan.c @@ -715,6 +715,11 @@ void br_vlan_flush(struct net_bridge *br) ASSERT_RTNL(); + /* delete auto-added default pvid local fdb before flushing vlans + * otherwise it will be leaked on bridge device init failure + */ + br_fdb_delete_by_port(br, NULL, 0, 1); + vg = br_vlan_group(br); __vlan_flush(vg); RCU_INIT_POINTER(br->vlgrp, NULL);