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Date:   Wed, 14 Dec 2022 21:17:10 +0200
From:   Leon Romanovsky <leon@kernel.org>
To:     Jakub Kicinski <kuba@kernel.org>
Cc:     Nir Levy <bhr166@gmail.com>, davem@davemloft.net,
        edumazet@google.com, pabeni@redhat.com,
        linux-atm-general@lists.sourceforge.net, netdev@vger.kernel.org
Subject: Re: [PATCH net v2] net: atm: Fix use-after-free bug in
 atm_dev_register()
Message-ID: <Y5ohNlJ4moB+wwdA@unreal>
References: <20221211124943.3004-1-bhr166@gmail.com>
 <Y5bUXjhM3mvUkwNL@unreal>
 <20221213191233.5d0a7c8f@kernel.org>
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On Wed, Dec 14, 2022 at 08:43:58AM -0800, Jakub Kicinski wrote:
> On Wed, 14 Dec 2022 09:51:09 +0200 Leon Romanovsky wrote:
> > > Also atm_dev_register() still frees the dev on atm_register_sysfs()
> > > failure, is that okay?  
> > 
> > Yes, the kernel panic points that class_dev (not dev) had use-after-free.
> 
> How is that possible? "class_dev" is embedded in dev (struct atm_dev).

Right, the more I think about this call trace, the less I'm sure.

Thanks