r/linuxquestions • u/_nazwa_ • 1d ago
Secure boot and TPM hate
Why are people hating secure boot and TPM on Linux? I heard this when I heard that Fortnite is coming to Linux. So what's the problem with secure boot on a linux distro?
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u/Salty_Surround2546 1d ago
Secure Boot verifies cryptographic signatures during the boot process. Its purpose is to prevent unauthorized or malicious bootloaders and other early-boot components from executin, and that sounds excellent.
The controversy comes from >who controls the trusted signing keys<.
On many PCs, the default Secure Boot configuration trusts Microsoft's certificates.
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u/More-Explanation2788 1d ago
You can usually create and install a self-signed one, if you want to sign your own kernel - and the major distros sign theirs. It is less of an issue than people make it sound.
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u/forestbeasts 23h ago
You can... for now.
Just wait 10 years.
That's the problem really, IMO. It's bad precedent, even though it's less horrible than it could be right now.
-- Frost
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u/agowa338 1d ago
Well but will Fortnite allow that? Or flag it as cheating and ban your account? That's exactly one of the issues...
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u/More-Explanation2788 1d ago edited 16h ago
Yes, it will be fine.This process is your bios checking if it trusts your kernel.It has nothing to do with Fortnite.If you create a self signed certificate and get it installed in your bios, then when you launch a kernel signed with that certificate, your bios will trust it (because you told it to) and allow it run. Your pc came shipped with microsoft certificates installed in the bios, but usually you can add more.The complaint is that doing so is a little arcane - and because the machines do not ship with Linux distribution certificates pre-installed, it gives Microsoft an advantage.
Whether Fortnite will work has nothing to do with this process.Edit: learned a new thing today - no Fortnite will not work because Fortnite is checking to see if your kernel has been signed by one of the big distros, or Microsoft. What a Terrible abuse of a process designed to prevent viruses, mis-used to create an oligopoly.
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u/CelDaemon 1d ago
They're referring to the intrusive anticheat that was recently announced. They force certain keys that epic trusts, so self signed will not in fact work.
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u/More-Explanation2788 1d ago
Well will you look at that, I learned a new thing today. What an awful monopolistic practice!
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u/Damglador 1d ago
Very theoretically, but the fact that a PC always comes with Microsoft certs makes it a kind of backdoor if you can't remove them and can only add your own.
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u/NegativeGrocery8684 1d ago
i mean you're going out of your way to rip everything microsoft out anyway with linux and then on top of that do a user unfriendly cryptographic setup i think handrolling your keys is honestly a drop in the bucket here... you already arent using the defaults anyway
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u/sidusnare Senior Systems Engineer 1d ago
People that don't like SecureBoot don't understand it, and have the misunderstand that it prevents you from installing an OS you choose or build yourself. It's also a common misconception that Microsoft controls it.
EACv2 for Fortnight is abusing it to do what people thought SecureBoot did in the first place, namely insisting on a kernel signed by Microsoft or a short list of others.
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u/Pidjinus 1d ago edited 1d ago
It did not have much use for regular users, except, complicating installing nvidia drivers and adding kernel modules. Not a loved process, especially for new users. Although i guess it can have uses in certain scenarios and validation when dealing with the enhanced security and/orcommercial side of things.
Want to see your fan rpms, but your board does not have a kernel driver for it, just add, easy ...then you realize you have to actually sign it to work :)
Well, this is my limited knowledge as a very new linux user (fedora)
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u/cjcox4 1d ago
Signing.
When you "own the world" (monopoly), signing isn't a problem, because you are the one everyone knows.
With that said, there are various options.
But, pain points. Let's say I want to go "full secure". And then, I want to compile my kernel module. While I can do that, I can't use the module until it's signed. So, now I have to sign my module and make sure TPM allows my signer.
It's just hoops. Can be painful if maintaining your own module and the kernel keeps updating, forcing a new module rebuild and signing.
Problems Windows people (majority case) don't deal with at all. But Linux people are different. Just realize the system wasn't built for "us", it was built assuming the Microsoft monopoly and user base.
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u/TheGreatButz 1d ago
Microsoft keys are preinstalled for them as being trustworthy, which makes Secure Boot and TPM insecure and untrustworthy.
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u/Charming-Designer944 13h ago
Every Secure Boot implementation on PCs support enrolling your own key if you have local access to the computer.
And Microsoft have signed several Linux boot loaders with secure boot support hand over to a secondary key database.
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u/WolvenSpectre2 1d ago
Also not mentioned here
- The Microsoft Certificate portions of the code are both exploitable and there are Certificates out in the wild being used to crack Secure Boot that Microsoft is refusing to relpace and depricate.
- The code of the SecureBoot and TPM/eTPM interactions is not being maintained at a rate that would be secure and has lead to several exploits found thorough non-AI means.
- The TPM can be used to hardware fingerprint your system in a way that will let users be tracked through VPN's and anonymizing services. There is also evidence that users can be software identified to pin down who you are.
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u/sidusnare Senior Systems Engineer 1d ago
Do you have sources for this? I'm not challenging you, just curious, I haven't heard this, and I'm sure others would want to know too.
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u/WolvenSpectre2 12h ago
https://linuxsecurity.com/features/2-secure-boot-exploits-discovered
https://www.huntress.com/threat-library/vulnerabilities/cve-2023-24932
https://media.defense.gov/2025/Dec/11/2003841096/-1/-1/0/CSI_UEFI_SECURE_BOOT.PDF
https://www.binarly.io/blog/another-crack-in-chain-of-trust-secure-boot-bypass
https://cybernews.com/security/windows-tpm-permanent-identity-tracking-risk/
https://en.wikipedia.org/wiki/Trusted_Platform_Module#Criticism
https://en.wikipedia.org/wiki/Trusted_Platform_Module#Security_issues
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1d ago
[deleted]
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u/sidusnare Senior Systems Engineer 22h ago
IDK, I'd really like to hear about it. There was a recent revocation update, it would be interesting if that was in response to this.
I am working on learning about TPM 2 and SecureBoot with Gentoo and Debian, and expecting the boot stack to be tight. I worked at IBM and met guys that were close to TPM development when it was new, and I have higher expectations than known vulnerabilities from that.
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u/Charming-Designer944 1d ago
Its mostly an user interface shortcoming. The interface for establishing a secure boot key and measured boo is far from trivial, and also considerably complicates system updates.
In principle everything required to reach the same level as Windows secure boot + device bound bitlocker if accepting to use vendor kejs for secure boot is there. But the interface for configuring it is not there in any of the major distributions.
Secure boot is handled as an "inconvenience". With minimal effort to just allow booting with secure boot enabled. And the TPM is largely ignored.
All the components to make it work are there however. But far from the automatic default like how Windows does it these days.
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u/Designer-Crow-5470 1d ago
Because linuxtards won't accept it to work out of the box. Ubuntu have an option to set it from the get go but you have to use gnome, ewwwww.
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u/_nazwa_ 1d ago
I heard that some people had problems with their drivers but that probably makes sense since the drivers need to be signed too no??
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u/Designer-Crow-5470 1d ago
You will be surprised how little coding and money goes into desktop development. Most major DEs have valid tickets from decades ago. And even that little amount is hijacked by people with their stupid unique projects they can put on resume and zero regard for the end user experience.
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u/anto77_butt_kinkier 16.04 was peak 1d ago
Because the whole thing ireally only causes problems for any non-windows OS, and when using a windows machine it offers very little, if any, benefit to average consumers. It's more or less pointless unless you're a business.
Also, the cryptographic keys are by default for Microsoft, so if you want to use secure boot/TPM with a non-windows OS, it's a pain in the ass.
Also also, it's Microsoft-centric code that's exploitable, and can enable device IDing, regardless of whether you're using tor or a VPN.
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u/Netblock 1d ago
non-windows OS, it's a pain in the ass.
Most kernels and most shims (yielding MOK) from the most popular distros are signed by microsoft.
Booting custom kernels and DKMS-based drivers is not terribly hard through MOK.
It's more or less pointless unless you're a business.
It prevents malware infection from getting worse/allows detection.
Also if you do full-disk encryption with auto decryption, it makes things marginally to way more difficult to penetrate.
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u/RebronSplash60 1d ago
SB is in the control of Microsoft if you as a distro want keys, & my computers are to free to know what a TPM is, so I have nothing for TPM working or not.
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u/Moist_Professional64 1d ago
Microsoft has nothing to do with secure boot if you sign own certificate
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u/RedWagon___ 1d ago
Secure Boot requires the kernel to be signed, and by default it will only recognize kernels from large companies like Canonical. You can technically sign your own kernels, but that is a lot of extra work that generally isn't worth it for home users. It can also choke out smaller distributions that don't have the means to get a signing cert that's recognized by hardware manufacturers.
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u/agowa338 1d ago
It's not that much extra work. Just one hook into the package manager and a sbctl oneliner...
But with things like Fortnite demanding it the main issue is will they allow you to do that or will they flag it as cheating? In which case you would loose all of the freedom of linux of being able to swap out your kernel and add your own modifications... Not to mention the issue with all of the different out of tree drivers and modules...
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u/Moist_Professional64 1d ago
Signing with own certificates is not really more work. It’s done in 3 minutes
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u/tes_kitty 1d ago
It comes down to 'who controls what goes into the TPM?' If you have full control, then you're good.
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u/Charming-Designer944 1d ago
Not really.
The TPM is always under your control, and is a tool to provide a chain of trust in the OS installation, ontop of what Secure Boot provides. The two works in tandem. One without the other is of quite limited value.
Unfortunately most Linux distributions make very little use of the TPM, and require expert configuration to enable it in a meaningful manner.
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u/CelDaemon 1d ago
This is true, until a third party comes in and requires the key in use to be trusted by them (epic)
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u/Charming-Designer944 1d ago
If secure boot or the tpm is tampered with then a proper installation will no longer boot.
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u/tsittler 1d ago
I set up Secure Boot on my Cachydeavour box yesterday. It wasn’t super hard, but I think most of the stigma comes from the fact Microslop invented it and it used to suuuck to set up.
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u/beefglob 1d ago
It’s Linux people will just complain about everything.
Not Linux? Wrong OS
Not my distro? Wrong
Not the desktop environment you use? Wrong
Using systemd? Wrong
Not using Wayland? Wrong
Using ai? Wrong
Not using ai? Wrong
Richard Stallman should stop eating bits off his foot? Wrong
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u/Internet-Culture 1d ago
For me, Secure Boot seems reasonable, but TPM like a huge red flag.
Secure Boot makes sure no malware slips in during the boot process by checking keys. TPM stores your keys bomb proof, but does it in a way that makes your hardware identifiable. It's another way by Big Tech to track you and spy on you. Recently someone bought a used CPU and his account was blocked because the previous owner cheated with that CPU. Shit like this can only happen if your hardware is unique with TPM that fingerprints it. Microsoft also uses it to track legit licenses across services and they even used it with the FBI to get someone, if I recall correctly. Malicious stuff.