Re: [PATCH] net: mdio: Fix a double free issue in the .remove function

[Russell King - ARM Linux admin]

On Wed, May 12, 2021 at 11:35:38PM +0200, Christophe JAILLET wrote:
> 'bus->mii_bus' have been allocated with 'devm_mdiobus_alloc_size()' in the
> probe function. So it must not be freed explicitly or there will be a
> double free.
> 
> Remove the incorrect 'mdiobus_free' in the remove function.

Yes, this looks correct, thanks.

Reviewed-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>

However, there's another issue in this driver that ought to be fixed.

If devm_mdiobus_alloc_size() succeeds, but of_mdiobus_register() fails,
we continue on to the next bus (which I think is reasonable.) We don't
free the bus.

When we come to the remove method however, we will call
mdiobus_unregister() on this existent but not-registered bus. Surely we
don't want to do that?

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