Why sysrq is limited to only "sync" command on official fedora kernel?

[Pete Travis]

On Feb 25, 2015 1:50 PM, "Reindl Harald" <h.reindl at thelounge.net> wrote:
>
>
>
> Am 25.02.2015 um 21:38 schrieb Zdenek Kabelac:
>
>> Dne 25.2.2015 v 18:44 Reindl Harald napsal(a):
>>>
>>>
>>> Am 25.02.2015 um 18:37 schrieb Paul Wouters:
>>>>
>>>> On Wed, 25 Feb 2015, Lennart Poettering wrote:
>>>>
>>>>> Hmm? Syncing is allowed to my knowledge. C-a-d and gdm allow a clean
>>>>> reboot/poweroff. But sysrq does an abnormal reboot/poweroff, which we
>>>>> cannot allow. Similar, remounting read-only is also security senstive,
>>>>> which we cannot allow.
>>>>>
>>>>> Without being logged in there's very little you can do on a host right
>>>>> now, and sysrq should not open up more there by default.
>>>>
>>>>
>>>> You must have forgotten your university days....
>>>>
>>>> The alternative to not being able to sync-umount-boot using sysrq is to
>>>> flip the switch. I'd rather have them use sysrq.
>>>>
>>>> I said it when they closed X ctrl-alt-backspace and I'll say it now.
>>>> When you are on console with the power plug, preventing these actions
>>>> is stupid
>>>
>>>
>>> when you are on a machine where you have pysical only keyboard and
>>> mouse it is
>>> not - not every PC stands in front of your face - think about kiosk
>>> mode and
>>> so on...
>>
>>
>> When I read such answers - I always wonder myself - how many kiosk ever
>> run Fedora...
>>
>> It's such a bad idea to optimize Fedora for one-in-milion users and
>> those 999.999 has to suffer instead of require 1 guy to configure more
>> secure version
>
>
> you can be sure that the need for sysrq is the one-in-milion users just
because i am a *heavy user* with a lot of setups and used it 4 times in the
past 12 years while restricted it to "kernel.sysrq = 20" long before the
systemd change
>
> it's such a bad idea to *not* optimize out-of-the box for security
>
> the ones which don't care can disable it, most won't care, nor have a
need nor do they even know about a lot of things - this users are also not
in the position to fix bad security defaults because they have no idea
about it
>
>
> --
>

The only time I've needed sysrq reboots in recent memory was while running
rawhide and knowingly venturing into uncharted territory.  If I'm not the
only one, would it make sense to include appropriate sysctl snippets in
fedora-release-rawhide ?

--Pete
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