RE: [PATCH net] net: phy: guard against accessing a NULL features bitmap

[Camelia Alexandra Groza]

> -----Original Message-----
> From: Andrew Lunn <andrew@xxxxxxx>
> Sent: Friday, January 11, 2019 15:38
> To: Camelia Alexandra Groza <camelia.groza@xxxxxxx>
> Cc: f.fainelli@xxxxxxxxx; hkallweit1@xxxxxxxxx; davem@xxxxxxxxxxxxx;
> oss@xxxxxxxxxxxx; netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: [PATCH net] net: phy: guard against accessing a NULL features
> bitmap
> 
> On Fri, Jan 11, 2019 at 01:56:46PM +0200, Camelia Groza wrote:
> > Since phy driver features became a link_mode bitmap, phy drivers that
> > don't have a list of features configured will cause the kernel to crash
> > when probed.
> 
> Hi Camelia
> 
> A NULL features is a driver bug. So i would prefer to solve this
> differently.
>
> Please make phy_driver_register() do a WARN_ON(!new_driver->features)
> and return -EINVAL.

I wasn't aware that features are mandatory. I'll make the change.

> Do you know of a specific driver which as a NULL value? We should fix
> that as well.

Yes, there are five drivers that don't have features configured: BCM8706, BCM8727, CS4340, TN2020 and KSZ8873MLL.

I'm planning to send patches on net-next for the Cortina and Teranetics ones at least, but fixing the generic crash was my priority.

Thanks,
Camelia