[PATCH 4.4 160/312] mdio-sun4i: oops in error handling in probe

[Greg Kroah-Hartman]

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

commit 227f33beab746aeec4ef3305bd17b1d374df09e7 upstream.

We could end up dereferencing an error pointer when we call
regulator_disable().

Fixes: 4bdcb1dd9feb ('net: Add MDIO bus driver for the Allwinner EMAC')
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Acked-by: Chen-Yu Tsai <wens@xxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/net/phy/mdio-sun4i.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/net/phy/mdio-sun4i.c
+++ b/drivers/net/phy/mdio-sun4i.c
@@ -134,6 +134,7 @@ static int sun4i_mdio_probe(struct platf
 		}
 
 		dev_info(&pdev->dev, "no regulator found\n");
+		data->regulator = NULL;
 	} else {
 		ret = regulator_enable(data->regulator);
 		if (ret)
@@ -149,7 +150,8 @@ static int sun4i_mdio_probe(struct platf
 	return 0;
 
 err_out_disable_regulator:
-	regulator_disable(data->regulator);
+	if (data->regulator)
+		regulator_disable(data->regulator);
 err_out_free_mdiobus:
 	mdiobus_free(bus);
 	return ret;