From: Vladimir Oltean Date: Sat, 23 Mar 2019 23:24:07 +0000 (+0200) Subject: net: dsa: Avoid null pointer when failing to connect to PHY X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=6146dd453e235c487d85ae4dc6cc08978a1c890f;p=openwrt%2Fstaging%2Fblogic.git net: dsa: Avoid null pointer when failing to connect to PHY When phylink_of_phy_connect fails, dsa_slave_phy_setup tries to save the day by connecting to an alternative PHY, none other than a PHY on the switch's internal MDIO bus, at an address equal to the port's index. However this does not take into consideration the scenario when the switch that failed to probe an external PHY does not have an internal MDIO bus at all. Fixes: aab9c4067d23 ("net: dsa: Plug in PHYLINK support") Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli Signed-off-by: David S. Miller --- diff --git a/net/dsa/slave.c b/net/dsa/slave.c index 093eef6f2599..6a8418dfa64f 100644 --- a/net/dsa/slave.c +++ b/net/dsa/slave.c @@ -1283,9 +1283,9 @@ static int dsa_slave_phy_setup(struct net_device *slave_dev) phy_flags = ds->ops->get_phy_flags(ds, dp->index); ret = phylink_of_phy_connect(dp->pl, port_dn, phy_flags); - if (ret == -ENODEV) { - /* We could not connect to a designated PHY or SFP, so use the - * switch internal MDIO bus instead + if (ret == -ENODEV && ds->slave_mii_bus) { + /* We could not connect to a designated PHY or SFP, so try to + * use the switch internal MDIO bus instead */ ret = dsa_slave_phy_connect(slave_dev, dp->index); if (ret) { @@ -1297,7 +1297,7 @@ static int dsa_slave_phy_setup(struct net_device *slave_dev) } } - return 0; + return ret; } static struct lock_class_key dsa_slave_netdev_xmit_lock_key;