netdev: bfin_mac: check for mii_bus platform data

If the platform data for the mii_bus is missing, gracefully error out
rather than deference NULL pointers.

Signed-off-by: Sonic Zhang <sonic.zhang@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/bfin_mac.c b/drivers/net/bfin_mac.c
index 2538eaa..39a54ba 100644 (file)
--- a/drivers/net/bfin_mac.c
+++ b/drivers/net/bfin_mac.c
@@ -1466,6 +1466,11 @@ static int __devinit bfin_mac_probe(struct platform_device *pdev)
        }
        pd = pdev->dev.platform_data;
        lp->mii_bus = platform_get_drvdata(pd);
+       if (!lp->mii_bus) {
+               dev_err(&pdev->dev, "Cannot get mii_bus!\n");
+               rc = -ENODEV;
+               goto out_err_mii_bus_probe;
+       }
        lp->mii_bus->priv = ndev;
 
        rc = mii_probe(ndev);
@@ -1511,6 +1516,7 @@ out_err_request_irq:
 out_err_mii_probe:
        mdiobus_unregister(lp->mii_bus);
        mdiobus_free(lp->mii_bus);
+out_err_mii_bus_probe:
        peripheral_free_list(pin_req);
 out_err_probe_mac:
        platform_set_drvdata(pdev, NULL);