From 7105b50b7eecae62cf6175507f9ea9ff60a55816 Mon Sep 17 00:00:00 2001
From: Vladimir Oltean <vladimir.oltean@nxp.com>
Date: Wed, 21 Jul 2021 19:24:02 +0300
Subject: [PATCH] net: bridge: guard the switchdev replay helpers against a
 NULL notifier block

There is a desire to make the object and FDB replay helpers optional
when moving them inside the bridge driver. For example a certain driver
might not offload host MDBs and there is no case where the replay
helpers would be of immediate use to it.

So it would be nice if we could allow drivers to pass NULL pointers for
the atomic and blocking notifier blocks, and the replay helpers to do
nothing in that case.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 net/bridge/br_fdb.c  | 3 +++
 net/bridge/br_mdb.c  | 3 +++
 net/bridge/br_vlan.c | 3 +++
 3 files changed, 9 insertions(+)

diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
index 2b862cffc03a0..47f190b6bfa37 100644
--- a/net/bridge/br_fdb.c
+++ b/net/bridge/br_fdb.c
@@ -760,6 +760,9 @@ int br_fdb_replay(const struct net_device *br_dev, const struct net_device *dev,
 	unsigned long action;
 	int err = 0;
 
+	if (!nb)
+		return 0;
+
 	if (!netif_is_bridge_master(br_dev))
 		return -EINVAL;
 
diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index 25d690b96cec1..e58f1a4ac9626 100644
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -617,6 +617,9 @@ int br_mdb_replay(struct net_device *br_dev, struct net_device *dev,
 
 	ASSERT_RTNL();
 
+	if (!nb)
+		return 0;
+
 	if (!netif_is_bridge_master(br_dev) || !netif_is_bridge_port(dev))
 		return -EINVAL;
 
diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c
index e66b004df7637..45ef07f682f19 100644
--- a/net/bridge/br_vlan.c
+++ b/net/bridge/br_vlan.c
@@ -1856,6 +1856,9 @@ int br_vlan_replay(struct net_device *br_dev, struct net_device *dev,
 
 	ASSERT_RTNL();
 
+	if (!nb)
+		return 0;
+
 	if (!netif_is_bridge_master(br_dev))
 		return -EINVAL;
 
-- 
2.30.2