Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!mips!apple!uokmax!munnari.oz.au!manuel!coombs!avalon From: avalon@coombs.anu.edu.au (Darren Reed) Newsgroups: comp.unix.amiga Subject: Re: interesting feature on AMIX.. Keywords: unix security, amix security, setuid Message-ID: Date: 24 Jun 91 03:30:03 GMT References: <13706@mentor.cc.purdue.edu> <1991Jun19.204906.19339@dvorak.amd.com> <426@hfsi.UUCP> <1991Jun21.201119.722@ckctpa.UUCP> <431@hfsi.UUCP> Sender: news@newshost.anu.edu.au Organization: Computer Services Centre, Australian National University Lines: 28 frank@hfsi.UUCP (Frank McPherson) writes: >In article <1991Jun21.201119.722@ckctpa.UUCP> crash@ckctpa.UUCP (Frank J. Edwards) writes: >>Suppose I make a floppy on my machine and put a copy of ksh on it. Then >>I make that ksh set-uid to root and mount it on your system. I execute >>that ksh and viola! I get the "#" prompt... >> >Would you have to meddle around with the KSH to make it set-uid to root? >My point here is, if you started up a ksh, even if from your own file >system, shoudn't it disallow you to setuid to root? If not, that is a [...] it is a bit of security problem, the Amiga3000UX should come with an entry for /dev/dsk/fd0 in one of the files in /etc (maybe fstab but commented out) to make it easier for novices to mount the floppy drive (not as easy as if sounds for a novice!) and to have it mount with the correct options - it is possible to mount a device under unix and have it IGNORE setuid bits - its just that most devices are mounted "setall". The default is "setall" i believe, so that if you mount a floopy without disabling setuid programs people can quite easily create setuid programs on floppy disks and execute them on your 3000. Under AMIX both sh/csh disallow you to run suid shell scripts - you need at least *one* shell which will let you create/run setuid shell scipts. darren