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Linux is a family of open source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991 by Linus Torvalds. Linux is typically packaged in a Linux distribution (or distro for short).

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Microsoft Proposes "Hornet" Security Module For The Linux Kernel (lore.kernel.org)

submitted 3 days ago* (last edited 3 days ago) by [email protected] to c/[email protected]

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https://www.phoronix.com/news/Microsoft-Hornet-Linux-LSM

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[–] [email protected] 49 points 2 days ago* (last edited 2 days ago) (3 children)

Ah yes, the "extended Berkeley Packet Filter".
Wikipedia:

eBPF is a technology that can run programs in a privileged context such as the operating system kernel.

Phoronix:

Hornet uses a similar signature verification scheme similar to that of kernel modules. A pkcs#7 signature is appended to the end of an executable file. During an invocation of bpf_prog_load, the signature is fetched from the current task's executable file. That signature is used to verify the integrity of the bpf instructions and maps which where passed into the kernel. Additionally, Hornet implicitly trusts any programs which where loaded from inside kernel rather than userspace, which allows BPF_PRELOAD programs along with outputs for BPF_SYSCALL programs to run.

So this is to make kernel-level instructions from userspace (something that's already happening) more secure.

The thread linked by the OP is Jarkko Sakkinen (kernel maintainer) seemingly saying "show your work, your patch is full of nonsense" in a patch submitted for review to the Linux kernel.
Edit: the OP has edited the link, it used to point to this comment in the mailing list chain.

[–] [email protected] 5 points 2 days ago

The thread linked by the OP is Jarkko Sakkinen (kernel maintainer) seemingly saying “show your work, your patch is full of nonsense” in a patch submitted for review to the Linux kernel.

That’s not what he’s saying. He’s saying: ‘You’re using terms which aren’t that familiar to everyone. Could you explain them?’

[–] [email protected] 7 points 2 days ago (1 children)

Loading BPF code from user space is, I hope, only possible with root access to the system. That would mean that an attacker needs root access to exploit BPF, but if an attacker has root access what stops him/her to do anything they want? At this time the system is lost anyway.

Or am I missing anything?

[–] [email protected] 11 points 2 days ago (2 children)

If the executable binary has to be signed with a key, similar to the module signing key, Microsoft could sign their binaries

This, along with secureboot, would prevent the owner of the machine from running eBPF programs Microsoft doesn't want you to run, even with root

[–] [email protected] 8 points 2 days ago

Yeah, that's why I am against Microsoft Keys on my systems

[–] [email protected] 7 points 2 days ago (2 children)

I fail to see the positive side of that...

[–] [email protected] 5 points 1 day ago

I wasn't trying to give a positive side, I was just explaining why Microsoft wants the feature

[–] [email protected] 7 points 2 days ago

Odds are because there isn't one.

Abusers will always try to justify their abuse by saying their victims "don't understand" why it's "necessary."

[–] [email protected] 13 points 2 days ago

Backdoor hidden in plain sight?