Ubuntu wants to strip some of GRUB features in 26.10 for security purposes

gorgoiler

Regarding dropping support for a LUKS encrypted /boot, one of the comments chimes in with “[but] full disk encryption is mandatory in many environments in Europe for security conformity”. Surely some user editable data has to be stored in plaintext to be able to boot a system? Does grub.cfg need to be signed by the trust chain to be able to boot?

longislandguido

Have they replaced it with grub-rs yet? On a more serious note, grub is ancient bloatware, it is way overcomplicated for what it does, it's asking to be replaced by systemd-boot distro-wide. Look at Apple and Microsoft's bootloaders, they are dead simple and have barely changed in 20 years, it makes you wonder how the hell grub was even conceived. It has config files for config files. grub tries to do the kitchen sink. But we live in a UEFI world now. Boot is simple. None of that is necessary anymore.

Zardoz84

I glad that I moved to green pastures... Aka Debian.

hedora

This comment is particularly concerning (as is the functionality regression implied by this new "more secure" approach): > This means for example, that an encrypted system must use an ext4 /boot partition; it is no longer possible to encrypt the /boot partition. So, they want to let attackers modify /boot, including grub.conf and the kernel command line? This is better? Look at all these fun knobs attackers will be able to turn! https://www.kernel.org/doc/Documentation/x86/x86_64/boot-opt... This lets you disable machine check exceptions + the iommu. That means it'll force people to use a configuration that lets attackers stick a memory probe hardware device into the system + bypass a bunch of hardware security checks. Nice! I also found module.sig_enforce which lets the attacker disable kernel module signature verification. Sadly, I couldn't find anything that lets you directly load a kernel module from /boot. However, init.rd lives in /boot. I wonder if its signature is verified or not. At the very least, this approach implies that attackers can piecemeal downgrade stuff early in the boot process.