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Comment by PunchyHamster | Hacker News Reader

tl;dr (not from article)

    echo -e 'install algif_aead /bin/false\n' > /etc/modprobe.d/disable-algif.conf

that just prevents the faulty module from loading. So you have time to fix it properly (kernel upgrade)

Technically there should be zero impact (the very very few tools that use it will fall back to userspace), I haven't even found that module loaded in infrastructure

Then check if it is loaded, and if it is, unload/reboot

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Though this won't work for some kernels:

If algif_aead was a builtin module, it needs to be disabled by adding initcall_blacklist=algif_aead_init to the boot cmdline.

However initcall_blacklist requires the kernel to be built with CONFIG_KALLSYMS.

Dumb question: is preventing the module from loading safe to blindly run on, e.g., Unraid, Proxmox, WSL2? Is it possible to break anything?

I would say any sanely written application would fall back to doing the requested operations in userspace if it cannot use the AF_ALG socket.

It could fail though. But I have not yet heard of anyone noticing big problems due to disabling the problematic modules. And I have not noticed any such issues on our systems at ${DAYJOB}.

IMHO, since these parts of the Linux kernel are so crappy I personally would say disabling them is a good default choice. YMMV. But if you encounter problems, then you can always re-enable the modules. (Preferably after upgrading your kernel, obviously.)

check if module is loaded. if it isn't nothing is using it and you can safely add it. I'd also imagine most software doesn't fail but just use userspace lib

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