Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!mailrus!b-tech!m-net!mju
From: mju@m-net.UUCP (Marc Unangst)
Newsgroups: comp.os.minix
Subject: Re: Superuser
Message-ID: <2662@m2-net.UUCP>
Date: 29 Dec 88 18:38:21 GMT
References: <1971@questar.QUESTAR.MN.ORG>
Reply-To: mju@m-net.UUCP (Marc Unangst)
Organization: M-NET, Ann Arbor, MI
Lines: 16

In article <1971@questar.QUESTAR.MN.ORG> jeff@questar.QUESTAR.MN.ORG (Jeff Holmes) writes:
>	a state that when I type 'su' it made me root without
>	asking for a password.  Logging out reset everything
>	to normal.  Anyone had this happen before? The setuid
>	bit is set (4755) and su is owned by root.
		    ^^^^      ^^^^^^^^^^^^^^^^^^^
I don't know if this is true for Minix, but for most Unixes, if su
is executed as root, it doesn't ask for a password.  Thus, by making
su SUID root, it is executing as root, and thus (thinking that you are
root) doesn't ask for a password.

-- 
"Don't find a fault, | Marc Unangst
find a remedy."      | UUCP: mju@m-net.ann-arbor.mi.us
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