How best get rid of SELinux?

[Tom Rivers]

Mike McCarty wrote:
> After a machine has been compromised, IMO it must be restored
> to a pre-compromise state. Trying to mitigate damage on a
> compromised machine is wrong-headed.
>

Mike,

I agree that compromised systems should be "fixed" so they aren't 
compromised anymore.  However, I don't agree that it is "wrong-headed" 
to attempt to mitigate the damage done to such a system.  Things like 
fire doors that close automatically when a fire is detected mitigate the 
damage a fire can do to a building.  Traction control and anti-lock 
brakes on vehicles attempt to keep the car from crashing once stability 
is compromised.  The firewall that contains a car's engine compartment 
and the airbag that deploys if the vehicle crashes both attempt to 
mitigate the damage done to the driver if something goes wrong.  Even 
white blood cells protect against pathogens that have breached the 
external defenses of our bodies in an attempt to mitigate damage to 
surrounding tissues.

None of the mechanisms I have just described work as expected 100% of 
the time but that is hardly reason to do away with any of them 
entirely.  As I'm sure you're aware, any good security posture has 
"defense in depth" as part of its scheme because it is historically a 
bad idea to rely on a single mechanism for overall security.  SELinux 
may not the best solution out there but it does serve a very important 
purpose - it mitigates system damage in order to preserve as much of the 
remaining system as possible.  I don't think anyone would argue that it 
makes sense to let someone who hacks a web server also get control of 
the credit card numbers stored in a database on the same machine.  
Likewise, with all due respect, it doesn't make sense to assert that 
trying to stop bad guys from doing all the damage they could is the 
wrong philosophy.  That would be like watching your entire home burn 
down from a fire on the stove because you feel the fire extinguisher, 
something that would minimize the fire damage, is somehow 
philosophically wrong.


Tom