linux-kernel - Re: [PATCH V2] net: mdio: thunder: Fix a double free issue in the .remove function

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Message-ID: <20210513081139.GT1336@shell.armlinux.org.uk>
Date:   Thu, 13 May 2021 09:11:39 +0100
From:   Russell King - ARM Linux admin <linux@...linux.org.uk>
To:     Christophe JAILLET <christophe.jaillet@...adoo.fr>
Cc:     andrew@...n.ch, hkallweit1@...il.com, davem@...emloft.net,
        kuba@...nel.org, david.daney@...ium.com, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org, kernel-janitors@...r.kernel.org
Subject: Re: [PATCH V2] net: mdio: thunder: Fix a double free issue in the
 .remove function

On Thu, May 13, 2021 at 09:44:49AM +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.

This still leaves the unregister of an allocated-but-unregistered bus,
which you disagreed with - but I hope as I've pointed out the exact
code path in your v1 patch, you'll now realise is a real possibility.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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