[patch 0/7 v2] kexec kernel efi runtime support

[H. Peter Anvin]

On 11/10/2013 06:13 PM, Dave Young wrote:
> 
> Huang Ying <ying.huang at intel.com> created the debugfs file for boot_params.
> His first version patch tried sysfs, but sysfs is not designed for such
> binary blobs so finally it go to debugfs.
> 

That is a misunderstanding.  Binary blobs can exist in sysfs as long as
the blob is something that is inherently a blob.  This is admittedly a
corner case, but it is without any doubt a protocol-defined binary
structure.

The reason it was put in debugfs is that there was no non-debug user for
it at the time.

> Any idea for this is welcome, till now I have no better idea for such kind
> of data. We should have another *fs instead of using debugfs.

The problem with debugfs is that things go into debugfs with largely no
auditing.  As a result, mounting debugfs is very likely to mean that
your system is exploitable one way or another.

	-hpa