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From:   David Howells <dhowells@redhat.com>
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To:     ebiederm@xmission.com (Eric W. Biederman)
Cc:     dhowells@redhat.com, torvalds@linux-foundation.org,
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Subject: Re: [PATCH 24/24] debugfs: Restrict debugfs when the kernel is locked down
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Date:   Wed, 11 Apr 2018 21:08:21 +0100
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Eric W. Biederman <ebiederm@xmission.com> wrote:

> Why is mounting debugfs allowed at all?  Last I checked (it has been a while)
> the code quality of debugfs was fine for debugging but debugfs was not
> safe to mount on a production system.
> 
> Maybe the code quality is better now but for a filesystem that is
> not supposed to be needed for developers letting us mount debugfs
> seems odd.

I agree.  But debugfs has been abused and it seems that there are some things
that use it as an interface between a kernel driver and the userspace side.

David