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>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/net/bfin_mac.c b/drivers/net/bfin_mac.c
index 2538eaa891ad..39a54bad397f 100644
--- 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);