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Subject: Re: [PATCH net 000/117] net: avoid to remove module when its
 debugfs is being used
From:   Johannes Berg <johannes@sipsolutions.net>
To:     David Laight <David.Laight@ACULAB.COM>,
        'Taehee Yoo' <ap420073@gmail.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
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        Nicolai Stange <nicstange@gmail.com>
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Date:   Thu, 08 Oct 2020 18:14:15 +0200
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On Thu, 2020-10-08 at 15:59 +0000, David Laight wrote:
> From: Taehee Yoo
> > Sent: 08 October 2020 16:49
> > 
> > When debugfs file is opened, its module should not be removed until
> > it's closed.
> > Because debugfs internally uses the module's data.
> > So, it could access freed memory.
> > 
> > In order to avoid panic, it just sets .owner to THIS_MODULE.
> > So that all modules will be held when its debugfs file is opened.
> 
> Can't you fix it in common code?

Yeah I was just wondering that too - weren't the proxy_fops even already
intended to fix this?

The modules _should_ be removing the debugfs files, and then the
proxy_fops should kick in, no?

So where's the issue?

johannes