Super User is a question and answer site for computer enthusiasts and power users. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I can get a list of modules using either lsmod or cat /proc/modules. Do the two approaches use the same mechanism to retrieve the modules? I want to know this as we could use it to find some hidden malicious modules.

share|improve this question
up vote 3 down vote accepted

They are both reading the same kernel interface to produce the list. However, a rootkit may alter lsmod to hide modules but there are myriad ways to read /proc/modules that would be near impossible for a rootkit to modify all of them.

If you're doing something programatic it doesn't really matter which one you use, but lsmod is much more human readable.

Update: To include examples.

cat /proc/modules
more /proc/modules
less /proc/modules
view /proc/modules
uniq /proc/moduels
uniq < /proc/modules
grep . /proc/modules
grep . < /proc/modules
awk '{print}' /proc/modules
awk '{print}' < /proc/modules
sed 's/(.)/$1/' < /proc/modules
echo "$(</proc/modules)"
perl -p -e ";" < /proc/modules
nc -l 11111 & nc localhost 11111 < /proc/modules

Etc., etc., etc. Anything that can read text can display the contents. These are just a few that I thought of in under a minute. If I thought about it I could come up with some really esoteric ways.

share|improve this answer
"there are myriad ways to read /proc/modules" could you please elaborate more on that? – user61954 Jan 9 '11 at 9:15
I'm not sure if you get notified that I edited my answer to include examples, but I did. – bahamat Jan 9 '11 at 9:41
Awesome man. Thanks for the info – user61954 Jan 9 '11 at 10:15

If the rootkit works at the kernel level (as a module for instance), you can not rely on the info provided by /proc/modules. Furthermore, you can not rely on lsmod either as it pretty-prints /proc/modules.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.