'exploitable' wasn't the best term, interpret it as 'triggerable' instead. other than that,
this code can be compiled as modular and hence loaded a lot later than system boot, it's up to
the sysadmin. in any case, we don't learn whether this potential NULL function pointer deref
occurs while the kernel holds any locks, resources, etc that may cause trouble. do you know
one way or another? that's the point we're trying to make!
PS: we're glad to have learned that at least older kernels aren't affected, would have been
nice to have a word about this in the commit because NULL *function* pointer dereferences
immediately trigger a mental 'look here, it's a potential full kernel compromise' alarm.