IB/mlx4: Verify net device validity on port change event

Processing an event is done in a different context from the one when
the event was dispatched. This requires a check that the slave
net device is still valid when the event is being processed. The check is done
under the iboe lock which ensure correctness.

Fixes: a57500903093 ('IB/mlx4: Add port aggregation support')
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index ac6e2b710ea6..b972c0b41799 100644
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -2697,8 +2697,12 @@ static void handle_bonded_port_state_event(struct work_struct *work)
         spin_lock_bh(&ibdev->iboe.lock);
         for (i = 0; i < MLX4_MAX_PORTS; ++i) {
                 struct net_device *curr_netdev = ibdev->iboe.netdevs[i];
+                enum ib_port_state curr_port_state;
 
-                enum ib_port_state curr_port_state =
+                if (!curr_netdev)
+                        continue;
+
+                curr_port_state =
                         (netif_running(curr_netdev) &&
                          netif_carrier_ok(curr_netdev)) ?
                         IB_PORT_ACTIVE : IB_PORT_DOWN;