net: phy: mdio-mux: Check return value of mdiobus_alloc()

mdiobus_alloc() might return NULL, but its return value is not checked in mdio_mux_init(). This could potentially lead to a NULL pointer dereference. Fix it by checking the return value Fixes: 0ca2997 ("netdev/of/phy: Add MDIO bus multiplexer support.") Signed-off-by: Tobias Klauser <[email protected]> Signed-off-by: David S. Miller <[email protected]>
torvalds · Dec 14, 2015 · 20b08e1 · 20b08e1
1 parent e5f5d74
commit 20b08e1
Showing 1 changed file with 6 additions and 1 deletion.
diff --git a/drivers/net/phy/mdio-mux.c b/drivers/net/phy/mdio-mux.c
@@ -149,9 +149,14 @@ int mdio_mux_init(struct device *dev,
 		}
 		cb->bus_number = v;
 		cb->parent = pb;
+
 		cb->mii_bus = mdiobus_alloc();
+		if (!cb->mii_bus) {
+			ret_val = -ENOMEM;
+			of_node_put(child_bus_node);
+			break;
+		}
 		cb->mii_bus->priv = cb;
-
 		cb->mii_bus->irq = cb->phy_irq;
 		cb->mii_bus->name = "mdio_mux";
 		snprintf(cb->mii_bus->id, MII_BUS_ID_SIZE, "%x.%x",