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Date:   Fri, 25 Feb 2022 09:53:35 +0100
From:   "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>
To:     "stern@rowland.harvard.edu" <stern@rowland.harvard.edu>
Cc:     "Zhang, Qiang1" <qiang1.zhang@intel.com>,
        Tejun Heo <tj@kernel.org>,
        syzbot <syzbot+348b571beb5eeb70a582@syzkaller.appspotmail.com>,
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        "balbi@kernel.org" <balbi@kernel.org>
Subject: Re: [syzbot] KASAN: use-after-free Read in dev_uevent
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On Thu, Feb 24, 2022 at 09:06:13PM -0500, stern@rowland.harvard.edu wrote:
> On Thu, Feb 24, 2022 at 11:37:39PM +0100, gregkh@linuxfoundation.org wrote:
> > On Thu, Feb 24, 2022 at 04:23:26PM -0500, stern@rowland.harvard.edu wrote:
> > > Can you tell us how this should be fixed?
> > 
> > It should be fixed by properly using the driver core to bind/unbind the
> > driver to devices like I mentioned previously :)
> 
> This would involve creating a "gadget" bus_type (or should it be a 
> device_type under the platform bus?) and registering the gadgets 
> on it, right?.

Yes.  Or you can use the aux bus for this, which might be easier.

> Similarly, the gadget drivers would be registered on 
> this bus.  I suppose we can control which drivers get bound to which 
> gadgets with careful matching code.

The aux bus might make this easier:
	Documentation/driver-api/auxiliary_bus.rst

thanks,

greg k-h