Path: utzoo!utgpu!water!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!bloom-beacon!bu-cs!encore!bzs@xenna
From: bzs@xenna (Barry Shein)
Newsgroups: comp.unix.wizards
Subject: Re: Reasons for restricting su privilege?
Message-ID: <3949@encore.UUCP>
Date: 22 Oct 88 19:37:01 GMT
References: <6606@pyr.gatech.EDU> <25003@tut.cis.ohio-state.edu>
Sender: news@encore.UUCP
Reply-To: bzs@xenna (Barry Shein)
Organization: Encore Computer Corp
Lines: 32
In-reply-to: karl@dinosaur.cis.ohio-state.edu (Karl Kleinpaste)

Although most anyone using a root account is subject to it there are
subtle and mysterious things Unix systems (and any system for that
matter) can do to you. Part of the trick is having habits which
restrict oneself to tried and true software (eg. bare commands rather
than whipped together shell scripts...note, no relation to suid shell
scripts.)

I think it was 4.2 (maybe all of them) that would *always* test:

	if(-x filename)

true if you were root and the file existed, regardless of its being
+x, for example. Strange and mysterious (see, we had a script which
allowed "user-friendly" access to chmod, you could say "setpriv public
files..." or "setpriv private files...", and it would, among other
things, attempt to see if the execute bit should be propagated, acted
real strange under a root account til I figured the above out.) No
flames about csh scripts etc, that's always nice advice, but misses
the point entirely.

Software running under root accounts can also inadvertently break
critical locks in the file system etc (eg. when they depend on failure
returns to honor simple-minded locking schemes, and root won't fail in
those cases, which is a feature, but not for such software.)

Then again, most sysadmins who must have root access probably have
only the vaguest idea about what I'm alluding to, or what software
might be affected.

Ah, fraught with danger, refreshing...

	-Barry Shein, ||Encore||