[PATCH AUTOSEL for 4.9 202/293] bridge: allow ext learned entries to change ports

From: Sasha Levin
Date: Sun Apr 08 2018 - 22:00:46 EST


From: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx>

[ Upstream commit 7597b266c56feaad7d4e6e65822766e929407da2 ]

current code silently ignores change of port in the request
message. This patch makes sure the port is modified and
notification is sent to userspace.

Fixes: cf6b8e1eedff ("bridge: add API to notify bridge driver of learned FBD on offloaded device")
Signed-off-by: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Roopa Prabhu <roopa@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
---
net/bridge/br_fdb.c | 28 ++++++++++++++++++++--------
1 file changed, 20 insertions(+), 8 deletions(-)

diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
index 6b43c8c88f19..f32b8138f9c8 100644
--- a/net/bridge/br_fdb.c
+++ b/net/bridge/br_fdb.c
@@ -1101,8 +1101,9 @@ void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
const unsigned char *addr, u16 vid)
{
- struct hlist_head *head;
struct net_bridge_fdb_entry *fdb;
+ struct hlist_head *head;
+ bool modified = false;
int err = 0;

ASSERT_RTNL();
@@ -1118,14 +1119,25 @@ int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
}
fdb->added_by_external_learn = 1;
fdb_notify(br, fdb, RTM_NEWNEIGH);
- } else if (fdb->added_by_external_learn) {
- /* Refresh entry */
- fdb->updated = fdb->used = jiffies;
- } else if (!fdb->added_by_user) {
- /* Take over SW learned entry */
- fdb->added_by_external_learn = 1;
+ } else {
fdb->updated = jiffies;
- fdb_notify(br, fdb, RTM_NEWNEIGH);
+
+ if (fdb->dst != p) {
+ fdb->dst = p;
+ modified = true;
+ }
+
+ if (fdb->added_by_external_learn) {
+ /* Refresh entry */
+ fdb->used = jiffies;
+ } else if (!fdb->added_by_user) {
+ /* Take over SW learned entry */
+ fdb->added_by_external_learn = 1;
+ modified = true;
+ }
+
+ if (modified)
+ fdb_notify(br, fdb, RTM_NEWNEIGH);
}

err_unlock:
--
2.15.1