The creator of systemd (Lennart Poettering) has recently created a new company dedicated to bringing hardware attestation to open source software.
What might this entail? A previous blog post could provide some clues:
So, let’s see how I would build a desktop OS. The trust chain matters, from the boot loader all the way to the apps. This means all code that is run must be cryptographically validated before it is run. This is in fact where big distributions currently fail pretty badly. This is a fault of current Linux distributions though, not of SecureBoot in general.
If this technology is successful, the end result could be that we would see our Linux laptops one day being as locked down as an Iphone or Android device.
There are lots of others who are equally concerned about this possibility: https://news.ycombinator.com/item?id=46784572
The thing is in such a case secureboot doesn’t help and is unnecessary. Secureboot only does anything for the concept of “trusted suppliers”.
If the system has available signing keys for itself, well, hypothetical malware could sign itself using those same keys The OS security mechanisms are the only things protecting that, and in which case the signature validation is redundant.
You can have trusted boot, e.g. LUKS volume sealed to TPM PCRs, but secureboot just doesnt make sense as a mechanism for a user to only trust themselves.
Thing is, that means you don’t really own the hardware that you buy, because a corporation is dictating what you can do with it even though it doesn’t belong to them. Most of us consider that unacceptable.