Somebody needs to drop the hammer on this whole "mapping address 0" thing. There's only like half a dozen user applications that would ever have a legitimate reason to map address 0, and they're all emulators for obsolete products.
The most ironic thing about all of this is that unless you're running some hardware from the late Jurassic period, you'll be able to run your emulator at full speed even without the hack. I'm sure the sysadmins of the world will be happy to know that although their boxes got rooted, at least they can run DOSBox at 50000x speed rather than 45000x.
And don't tell me that we're going to eliminate NULL pointer dereferences from the kernel. That will never happen.
The real bug here is that we are not properly enforcing the mmap_min_addr setting. Running a properly configured selinux system should never be less secure than running with selinux off. That's just FAIL.