Re: [PATCH v2] lan743x: Fix for potential null pointer dereference

From: Andrew Lunn
Date: Sun Nov 01 2020 - 15:38:39 EST


On Sun, Nov 01, 2020 at 10:54:38PM +0300, Sergej Bauer wrote:
> > > Signed-off-by: Sergej Bauer <sbauer@xxxxxxxxxxx>
> >
> > * I miss a change description here.
> The reason for the fix is when the device is down netdev->phydev will be NULL
> and there is no checking for this situation. So 'ethtool ethN' leads to kernel
> panic.

> > > @@ -809,9 +812,12 @@ static int lan743x_ethtool_set_wol(struct net_device
> > > *netdev,>
> > > device_set_wakeup_enable(&adapter->pdev->dev, (bool)wol->wolopts);
> > >
> > > - phy_ethtool_set_wol(netdev->phydev, wol);
> > > + if (netdev->phydev)
> > > + ret = phy_ethtool_set_wol(netdev->phydev, wol);
> > > + else
> > > + ret = -EIO;

-ENETDOWN would be better, it gives a hit that WoL can be configured
when the interface is configured up.

Andrew