Subject: [PATCH 11/46] net: bridge: delete local fdb on device init failure

From: Nikolay Aleksandrov <[email-masked]>
Date: Mon, 29 Jul 2019 12:28:41 +0300

[ Upstream commit d7bae09fa008c6c9a489580db0a5a12063b97f97 ]

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: [email-masked]
Fixes: 5be5a2df40f0 ("bridge: Add filtering support for default_pvid")
Signed-off-by: Nikolay Aleksandrov <[email-masked]>
Signed-off-by: David S. Miller <[email-masked]>
---
 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 f47f526b4f19..a764459f4b66 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);
-- 
2.20.1