net/mlx5e: Fix possible non-initialized struct usage

If mlx5e_devlink_port_register() fails, driver may try to register
devlink health TX and RX reporters on non-registered devlink port.

Instead, create health reporters only if mlx5e_devlink_port_register()
does not fail. And destroy reporters only if devlink_port is registered.

Also, change mlx5e_get_devlink_port() behavior and return NULL in case
port is not registered to replicate devlink's wrapper when ndo is not
implemented.

Signed-off-by: Vladyslav Tarasiuk <vladyslavt@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

1 files changed, 7 insertions, 2 deletions

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/devlink.c b/drivers/net/ethernet/mellanox/mlx5/core/en/devlink.c
index 765f3064689d..0dd7615e5931 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/devlink.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/devlink.c
@@ -55,12 +55,17 @@ void mlx5e_devlink_port_unregister(struct mlx5e_priv *priv)
 {
 	struct devlink_port *dl_port = mlx5e_devlink_get_dl_port(priv);
 
-	devlink_port_unregister(dl_port);
+	if (dl_port->registered)
+		devlink_port_unregister(dl_port);
 }
 
 struct devlink_port *mlx5e_get_devlink_port(struct net_device *dev)
 {
 	struct mlx5e_priv *priv = netdev_priv(dev);
+	struct devlink_port *port;
 
-	return mlx5e_devlink_get_dl_port(priv);
+	port = mlx5e_devlink_get_dl_port(priv);
+	if (port->registered)
+		return port;
+	return NULL;
 }