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Re:Linux and Secure Boot certificate expiration by saidinesh5 on Friday July 18, 2025 @02:54AM (#44601960)
Just out of curiosity, how good is the secure boot experience these days?

I've had to disable it on all my installations because of either nvidia drivers or virtual box modules. In general Arch based distros didn't seem too friendly for secure boot set up.

Re:Linux and Secure Boot certificate expiration by paulv on Friday July 18, 2025 @03:22AM (#44602120)
My experience as a long time Linux user (since 1997, so admittedly stuck with some bad habits from when things were actually hard to get working) has been that things are kind of confusing if you deviate from the golden path, but if you are on the golden path you won't ever notice that it is turned on.

The laptops I have gotten from eg Dell with Linux pre installed have just worked. Machines I have upgraded through many versions of Ubuntu (lts versions of 16-24) were weirdly broken for a while when I first turned secure boot on while I figured it out, but that seemed reasonable for such a pathological case. Machines I have installed Debian on in the last few years have been fine, except for some problems when I was booting from a software raid array, but that is because I was using 2 identical drives and I kept getting them confused in the UEFI boot configuration.

I have not used them on machines with nvidia, vbox, or other out-of kernel-tree modules though.

Re:Linux and Secure Boot certificate expiration by bravetraveler on Friday July 18, 2025 @03:01AM (#44602000)
Signature maintenance for modules can be fully automated. Enrollment requires navigating a mildly-intimidating interface a single time to accept the new PKI.

Fine for systems you physically manage, anything remote in a datacenter I wouldn't bother (without external motivation)

Re:Linux and Secure Boot certificate expiration by mormegil on Friday July 18, 2025 @03:59AM (#44602333)
Which is strange because secure boot should be useful in _exactly_ the situation you don't have physical control of the HW, shouldn't it? I guess the threat model for a common not-that-important company does not include evil data center (and it's dubious if SecureBoot would protect you in reality), but wasn't that one of the motivations?
Re:Linux and Secure Boot certificate expiration by ChocolateGod on Friday July 18, 2025 @04:11AM (#44602396)
[delayed]
Re:Linux and Secure Boot certificate expiration by the8472 on Friday July 18, 2025 @05:55AM (#44602912)
With a UKI the initramfs gets signed too, doesn't it?
Re:Linux and Secure Boot certificate expiration by vbezhenar on Friday July 18, 2025 @06:25AM (#44603086)
There are ways to solve that issue. But I think that you're correct, pinpointing the core issue with popular Linux distributions. It doesn't have to be this way, though.

1. You can sign and verify initramfs, it's supported by bootloaders.

2. You can merge kernel and initramfs into UKI and sign the whole image.

I don't know why that's not implemented.

Re:Linux and Secure Boot certificate expiration by ChocolateGod on Sunday July 20, 2025 @05:45AM (#44623428)
For UKI I imagine a big hurdle is the size of the images (given /boot/efi is usually only big enough for bootloaders, not kernels and initram) and custom kernel modules (e.g. Nvidia).

There was some systemd work on a spec for a boot partition to extend the efi partition for storing kernel images and initramfs, but I don't think any distro currently defaults to it on.

I think hibernation is currently also broken, since the hibernation file is stored unencrypted by default and thus can't be used with secure boot.

Re:Linux and Secure Boot certificate expiration by bravetraveler on Friday July 18, 2025 @04:10AM (#44602388)
Aye, though an evil maid has higher barriers and more paperwork in a DC.

I hesitate based on that mitigation and the untold operational pain. Sometimes it's worth it, other times it isn't.

Re:Linux and Secure Boot certificate expiration by michaelt on Friday July 18, 2025 @04:59AM (#44602630)
> Which is strange because secure boot should be useful in _exactly_ the situation you don't have physical control of the HW, shouldn't it?

One of the ways you can introduce your own signing key is as a Machine Owner Key, using the "MOK Manager"

But a design goal of this software was: We don't want malware with root to be able to introduce a MOK without the user's consent, as then the malware could sign itself. So "MOK Manager" was deliberately designed to require keyboard-and-mouse interaction, early in boot before the network has been brought up.

Of course if your server has a KVM attached, you can still do this remotely, I guess.

Re:Linux and Secure Boot certificate expiration by pbhjpbhj on Friday July 18, 2025 @03:48AM (#44602279)
Every couple of years MS do an update that messes up multi-boot/dual boot. I'm sure it's on purpose at this point, and relatively sure "Secure Boot" is how they achieve it.

Still on Windows only for kids games. Linux user since last millennium.

Re:Linux and Secure Boot certificate expiration by ChocolateGod on Friday July 18, 2025 @04:13AM (#44602403)
[delayed]
Re:Linux and Secure Boot certificate expiration by account42 on Friday July 18, 2025 @07:30AM (#44603512)
The idea that MS should be able make orders that distros then have to follow is insane. If MS breaks something it absolutely is their fault.
Re:Linux and Secure Boot certificate expiration by ChocolateGod on Sunday July 20, 2025 @05:41AM (#44623400)
No it's not. Microsoft has to disable outdated and vulnerable signed bootloaders to stop them being used for secure boot bypasses. Microsoft worked with RH to get things updated which they did, it's just distros for caught slacking and were shipping an outdated vulnerable boot loader.

I know it's the norm to bash Microsoft and they do a lot of crappy things, but in this case it was just certain distros not taking security updates seriously, which is why a lot never broke (such as Fedora)

Re:Linux and Secure Boot certificate expiration by noAnswer on Friday July 18, 2025 @07:33AM (#44603534)
So Windows installs something that brakes Linux boot. How are you supposed to boot Linux to install a fix? Am I expected to reboot into a different OS twice a day and check for updates? Am I slacking for not doing so?!
Re:Linux and Secure Boot certificate expiration by ChocolateGod on Sunday July 20, 2025 @05:43AM (#44623412)
No, Windows updated a UEFI component that disables outdated and vulnerable bootloaders to stop them being used as secure boot bypasses.
Re:Linux and Secure Boot certificate expiration by blkhawk on Friday July 18, 2025 @04:09AM (#44602385)
As a Linux-only gamer since 2019 I wonder what kids games you are talking about?
Re:Linux and Secure Boot certificate expiration by repstosb on Friday July 18, 2025 @04:44AM (#44602555)
There are things like Roblox that are really only usable under Windows due to a perverse idea of what "anti-cheat" should look like.
Re:Linux and Secure Boot certificate expiration by 71bw on Friday July 18, 2025 @06:33AM (#44603121)
Re:Linux and Secure Boot certificate expiration by pbhjpbhj on Friday July 18, 2025 @09:08AM (#44604272)
I can confirm Sober works really well, possibly slightly smoother than the Windows client.

I couldn't get it to run via Proton/Wine at all.

Re:Linux and Secure Boot certificate expiration by blkhawk on Friday July 18, 2025 @05:52AM (#44602892)
ah, I almost mentioned roblox but checking protondb it has gold status. So it should work?
Re:Linux and Secure Boot certificate expiration by pbhjpbhj on Friday July 18, 2025 @09:22AM (#44604378)
I've stopped trying to fight to install things on Linux. Anything with kernel level anticheat it seems is torment. They okay Fortnite, and quite a bit of Marvel Rivals (which initially worked, then stopped, I see reports suggesting it's working again but I don't have time to be full-time support to keep things running smoothly).

We do use Kubuntu for games that run in it without drama - Risk of Rain, Roblox (via Sober), browser games, CS2.

They also are expected to use Microsoft Office for school (UK), it's possible to work that online, but the experience is worse, slower, more prone to issues it seems.

Fwiw, I've been a Linux distro user for decades and was Linux only until the first child got to highschool. Microsoft's "educational" policy works for them!

Re:Linux and Secure Boot certificate expiration by chaz6 on Friday July 18, 2025 @04:34AM (#44602520)
I use Fedora and have it enabled. Every time there is a kernel update I have to run a script to re-compile and sign the vmware drivers. I could probably figure out how to do it with dkms at some point. Every now and then, there's a kernel change big enough to make the vmware drivers stop working so I have to get a new patch.
Re:Linux and Secure Boot certificate expiration by michaelt on Friday July 18, 2025 @04:45AM (#44602559)
I would rate the experience as 6.5/10

If you use a major distro like Ubuntu, you might find Secure Boot works out-of-the-box, with no need to dick about with 'machine owner keys' and suchlike.

Ubuntu has packages like "linux-modules-nvidia-550-generic" containing a version of nvidia's 550 drivers signed with canonical's keys. If the stars align and that package gets installed, you'll have nvidia drivers that work under secure boot.

They also have a second mechanism. You can set up a 'machine owner key' (MOK) then software updates will trigger automatically building new nvidia kernel modules, using 'dkms' then sign them with the MOK allowing them to work under secure boot.

The problem is this process can be a bit wonky. The MOK setup process involves rebooting and going through the "MOK Manager", an interface that looks like something from the 1980s. If you didn't know to expect it, or what it's there for, or you don't speak English, it's easy to hit the wrong thing and not set up your MOK. And it only shows up for a single boot, unless you know an arcane terminal command.

And if you run into any problems during the setup process - you're going to be researching the fix on your phone, because your PC isn't booting.

Meanwhile, the third option of just turning off secure boot is easy (assuming you know what the BIOS is) and it works every time. So a lot of 'how to set up nvidia drivers' guides just recommend doing that.

Although I complain about it, I find it impressive things like dynamically compiling and signing kernel modules works as well as it does - especially as so much of it is maintained by volunteers, selflessly giving up their free time when they could have simply turned off secure boot in their BIOS too.

Re:Linux and Secure Boot certificate expiration by charcircuit on Sunday July 20, 2025 @04:07AM (#44622936)
Mok has a big problem where malware can get you to sign malicious code with it. Having the signing keys be accessible to the end user is dangerous.
Re:Linux and Secure Boot certificate expiration by icar on Friday July 18, 2025 @04:53AM (#44602593)
With Arch, I've been using SecureBoot since sbctl [0] was released with 0 issues. Granted, I don't use any Nvidia hardware.

[0] https://github.com/Foxboron/sbctl

Re:Linux and Secure Boot certificate expiration by EnPissant on Friday July 18, 2025 @05:18AM (#44602696)
UKI + secure boot works really well, but it is somewhat manual of a set up on Arch (what isnt).

If properly set up the only files you generate are:

- /efi/loader/random-seed

- /efi/EFI/Linux/arch-linux.efi

- /efi/EFI/Linux/arch-linux-fallback.efi

and the .efi are all automatically signed by hooks.

You can even skip a bootloader and boot the images directly.

Re:Linux and Secure Boot certificate expiration by IHawkMike on Friday July 18, 2025 @08:03PM (#44611213)
I just finished setting this up and it's definitely this easy. The hardest part was growing the ESP to dual boot with Windows but that is basically just copy/paste the files to a bigger partition and change the partition type GUIDs.

Most of the guides focus on creating the PK, KEK, and db certs for enrolling/updating certs from userspace with signed .auth files but that is kind of pointless and seriously over-complicates it. I just created a 20-year db key pair with openssl (and PK and KEK just to make sbctl happy due to a bug), then installed the public db cert into the UEFI manually via the ESP. Didn't even need to use setup mode, although I suspended BitLocker on the Windows partition to let it reseal its key with the new PCR 7 measurement after the db update.

To finish securing it I have a separate key for PK and KEK and have already installed Microsoft's 2023 UEFI certs in the db (and added the 2011 cert to dbx with the updated bootmgr).

Re:Linux and Secure Boot certificate expiration by EnPissant on Saturday July 19, 2025 @05:38AM (#44613963)
I just used sbctl to generate and install a platform key in setup mode. It worked well.
Re:Linux and Secure Boot certificate expiration by CoolCold on Friday July 18, 2025 @05:31AM (#44602761)
just doublechecked with "Confirm-SecureBootUEFI" - says True on my laptop which used > 1 year. I'm pretty sure on the previous system which was used for 4 years it was on too - have not noticed any issues.

Windows 10 and then 11

Re:Linux and Secure Boot certificate expiration by jeroenhd on Friday July 18, 2025 @05:33AM (#44602773)
It works pretty well out of the box unless you're trying to combine Linux with Nvidia hardware. Even with Nvidia hardware it doesn't take that much effort to make it work, but as usual, Nvidia requires taking extra steps.

What Linux is really lacking is a user-friendly method for enrolling your own keys, which would instantly solve all the Nvidia/firmware updater/custom bootloader problems. The command line tools are slowly getting easier to use, but there's no guided instruction flow.

Re:Linux and Secure Boot certificate expiration by vbezhenar on Friday July 18, 2025 @06:10AM (#44603004)
I'm using Arch and it was very easy to configure secure boot. I don't know why you think it's not friendly. I'm using UKI, so no bootloader at all, my UKI is signed by my own key which is installed into UEFI. Most of sign process is handled by systemd, so most of it is already integrated into the base system.
Re:Linux and Secure Boot certificate expiration by Avamander on Friday July 18, 2025 @12:57PM (#44607063)
One checkbox during install when using Ubuntu with custom DKMS modules. That's it. For the past five or more years.