nxusb kernel module is rejected from kernel due to SecureBoot

[a4paper]

Environment: Ubuntu 20.04 SecureBoot-enabled

How to reproduce:
– Install NoMachine 7.6.2

$ sudo insmod /usr/NX/bin/drivers/nxusb.ko
insmod: ERROR: could not insert module /usr/NX/bin/drivers/nxusb.ko: Operation not permitted

Inspecting /var/log/syslog lead me to the following entry:
[171129.286477] Lockdown: insmod: unsigned module loading is restricted; see man kernel_lockdown.7

I think this is because nxusb module is not signed one. Of course we, users are building nxusb binaries on our machines in home-brewing way during NoMachine installation process.
Almost the same thing happens for recent (Big Sur) macOS releases.

I know disabling SecureBoot is a *recommended* solution here, but I doubt lowering security level is a *correct* way. Could you please consider providing signed binaries officially?

[Giorgi-G.]

Hi,

There is a way to simply self-sign nxusb.ko driver on your side, the detailed instruction can be found here: https://knowledgebase.nomachine.com/AR05O00929.

[a4paper]

Oh great! Thank you so much!

[Author]

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