[PATCH 4.20 116/183] net: bridge: Mark FDB entries that were added by user as such

[Greg Kroah-Hartman]

4.20-stable review patch.  If anyone has any objections, please let me know.

------------------

[ Upstream commit 710ae72877378e7cde611efd30fe90502a6e5b30 ]

Externally learned entries can be added by a user or by a switch driver
that is notifying the bridge driver about entries that were learned in
hardware.

In the first case, the entries are not marked with the 'added_by_user'
flag, which causes switch drivers to ignore them and not offload them.

The 'added_by_user' flag can be set on externally learned FDB entries
based on the 'swdev_notify' parameter in br_fdb_external_learn_add(),
which effectively means if the created / updated FDB entry was added by
a user or not.

Fixes: 816a3bed9549 ("switchdev: Add fdb.added_by_user to switchdev notifications")
Signed-off-by: Ido Schimmel <idosch@xxxxxxxxxxxx>
Reported-by: Alexander Petrovskiy <alexpe@xxxxxxxxxxxx>
Reviewed-by: Petr Machata <petrm@xxxxxxxxxxxx>
Cc: Roopa Prabhu <roopa@xxxxxxxxxxxxxxxxxxx>
Cc: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx>
Cc: bridge@xxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 net/bridge/br_fdb.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
index e56ba3912a905..8b8abf88befbd 100644
--- a/net/bridge/br_fdb.c
+++ b/net/bridge/br_fdb.c
@@ -1102,6 +1102,8 @@ int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
 			err = -ENOMEM;
 			goto err_unlock;
 		}
+		if (swdev_notify)
+			fdb->added_by_user = 1;
 		fdb->added_by_external_learn = 1;
 		fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
 	} else {
@@ -1121,6 +1123,9 @@ int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
 			modified = true;
 		}
 
+		if (swdev_notify)
+			fdb->added_by_user = 1;
+
 		if (modified)
 			fdb_notify(br, fdb, RTM_NEWNEIGH, swdev_notify);
 	}
-- 
2.19.1