From owner-freebsd-hackers  Mon Oct 27 23:01:01 1997
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To: Terry Lambert <tlambert@primenet.com>
cc: Don.Lewis@tsc.tdk.com (Don Lewis), jamil@trojanhorse.ml.org,
        thorpej@nas.nasa.gov, freebsd-hackers@FreeBSD.ORG
Subject: Re: Possible SERIOUS bug in open()? (Big time bug) 
In-reply-to: Your message of "Tue, 28 Oct 1997 04:08:00 GMT."
             <199710280408.VAA05972@usr08.primenet.com> 
Date: Tue, 28 Oct 1997 00:00:21 -0700
From: Dave Andersen <angio@angio.net>
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> > I don't think administrators who remove "r" access to keep users
> > from copying executables would like this, since the users could
> > just switch to a copying program that uses mmap.
> 
> A user can just ctrl-\ the thing and get a core and "undump" it now.
> 
> If it's a net program, they can just download it.

  In reverse order:

   a) You'd most commonly do this to a program you wrote yourself to
      protect it from exploitation and/or examination, not for
      something you got off the net.

   b) Setuid programs haven't dumped core since the ftpd problem 
      a while ago.

> > In some environments it might not be acceptable to get even this much
> > access, so it might make sense to allow the administrator to disable
> > core file generation and the ability to attach a debugger if you don't
> > have "r" access.
> 
> Well, that's the next logical paranoid step, of course... ;-).

meowy /tmp >> gdb ./setuidme
...
GDB 4.16 (i386-unknown-freebsd),

./setuidme: Permission denied.

(gdb)

    -Dave