UNIX for Dummies Questions & Answers

Can anybody tell me if there is a security issue with root using/pointing to /usr, like for example /usr/bin/ksh? Why not point to /bin/ksh instead?
Any risk involved doing that?
Thanks
Norgaard

Are the two files using the same version of ksh? Are the permissions on the file set the same? Could either file be changed by a non-root user due to the permissions on the directories or files?

Same version and same rights. The question is/was meant to be more fundamental as in, is it really a good thing to let root point to anything in /usr? By default, I mean. My understanding always was that root should not point to /usr to be 100% sure that changes meant to impact other users do not impact root. maybe it is "religion", but in general I'd have root go to any application and utility through an as direct and "pure" access as possible. In this case, my gut feeling is that /bin/ksh is better than /usr/bin/ksh. Obviously the 2 can have the same rights and it is even possible that the /bin version could be older than the /usr/bin version. That would be another problem.

Depends on where you're working, I imagine. At my current workplace, it doesn't matter -- we have binaries in many varied places (/opt, /bin, /usr, /home, etc.).

Well, I guess that that means "no particular risk"?

I wouldn't imagine it as a risk, no. Just against policy and, sometimes, sanity

It's not a security issue -- just having a file in /usr/ doesn't magically make it vulnerable, what matters is the permissions -- but it could be a maintenance problem. When /usr is a partition, and it fails to mount for some reason, root won't be able to login to fix it.