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From: nagel@paris.ics.uci.edu (Mark Nagel)
Newsgroups: comp.os.minix
Subject: Re: Superuser
Message-ID: <2647@paris.ics.uci.edu>
Date: 31 Dec 88 02:20:27 GMT
References: <1971@questar.QUESTAR.MN.ORG> <2662@m2-net.UUCP>
Sender: news@paris.ics.uci.edu
Reply-To: nagel@paris.ics.uci.edu (Mark Nagel)
Organization: University of California, Irvine - Dept of ICS
Lines: 17
In-reply-to: mju@m-net.UUCP (Marc Unangst)

In article <2662@m2-net.UUCP>, mju@m-net (Marc Unangst) writes:
|In article <1971@questar.QUESTAR.MN.ORG> jeff@questar.QUESTAR.MN.ORG (Jeff Holmes) writes:
|>	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.

Su *has* to be setuid root, or else how could it perform the necessary
setuid for you?  It doesn't ask for a password only when the real uid
is root.

Mark Nagel @ UC Irvine, Dept of Info and Comp Sci
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