modprobe.d: Blacklist, Options, and Load-at-Boot

MediumKernel Security & Rootkits15-25 min

The brief

Three persistent kernel-module changes, all via drop-in config. Your assignment is in /root/case/assignment.env (BLACKLIST, OPT_MODULE, OPTION, LOAD_MODULE).

1. Blacklist BLACKLIST so it never auto-loads — /etc/modprobe.d/….conf with blacklist BLACKLIST.

2. Set an option on OPT_MODULE — /etc/modprobe.d/….conf with options OPT_MODULE OPTION.

3. Load LOAD_MODULE at boot — /etc/modules-load.d/….conf containing the module name on its own line.

Grading reads the .conf files under /etc/modprobe.d/ and /etc/modules-load.d/ — the only ones modprobe and systemd-modules-load read — (it doesn't touch the running kernel). On a live host, blacklist/options apply on the next modprobe (and after dracut -f for early-boot); modules-load.d loads at boot. See /root/case/brief.txt.

What you'll do

Blacklist a module via a modprobe.d drop-in
Pass an option to a module via modprobe.d
Load a module automatically at boot via modules-load.d
Understand the modprobe.d vs modules-load.d split

Hands-on lab: you work on a real Linux box in your browser, graded on the machine's actual state.