Re: [PATCH] net: mdiobus: Fix memory leak in __mdiobus_register

On Tue, Sep 28, 2021 at 04:52:07PM +0300, Dan Carpenter wrote:

On Tue, Sep 28, 2021 at 01:58:00PM +0100, Russell King (Oracle) wrote:

quoted

This thread seems to be getting out of hand.

The thread was closed.  We need to revert Yanfei's patch and apply
Pavel's patch.  He's going to resend.

quoted

So, I would suggest a simple fix is to set bus->state to
MDIOBUS_UNREGISTERED immediately _after_ the successful
device_register().

Not after.  It has to be set to MDIOBUS_UNREGISTERED if device_register()
fails, otherwise there will still be a leak.

Ah yes, you are correct - the device name may not be freed. Also...

 * NOTE: _Never_ directly free @dev after calling this function, even
 * if it returned an error! Always use put_device() to give up your
 * reference instead.

So yes, we must set to MDIOBUS_UNREGISTERED even if device_register()
fails.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!