Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!unmvax!nmtsun!peter@hydrovax.nmt.edu
From: peter@hydrovax.nmt.edu (Peter A. Blemel)
Newsgroups: comp.sys.ibm.pc.rt
Subject: Priorities and AIX 2.2.1
Message-ID: <3485@nmtsun.nmt.edu>
Date: 13 Nov 89 04:03:47 GMT
Sender: news@nmtsun.nmt.edu
Organization: New Mexico Tech Hydrology Program
Lines: 34


Hi Folks,

   I have spent much time trying to figure out why Interleaf kills
the system. We have a 135 and when tps starts, everything else stops.

   I tried nicing (sp?), sticky-bitting, and even stripping the symbol
table. I wish I were more of a systems type.

   Many hours and faxes into the search, IBM tells me that the program
runs ON the VRM at an elevated priority. I checked, and sure enough -- the
program starts niced and then drops to prio 10. I have looked, and nothing
is setuid root (I have looked for any and all 'tps*' and 'leaf*' execs), the
owner (leafadm) is now in its own group, and I run it from an unpriveleged
account. It still can change its nice value.

   I was under the impression that only a priv'd account could change the
nice value of an executing program. If this is correct, then how can
Interleaf change its priority from a vanilla account? Is this an indication
of some unknown security hole (how is it getting authorization to elevate
its priority)?

   The core exec is tps4.0. Issuing ps -ael in a 'while true' loop shows
that tps4.0 is the only interleaf related program executing for a second
or so before and at the time the nice value changes. This thing kills
a very expensive machine. I'd really appriciate any information on how
to lower its prio and free the CPU. Is the permission set in the a.out
header (a.out.h or vrm.h)? Can I modify the header to fix the problem?

Thanks,
Peter
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peter@hydrovax.nmt.edu
peter@amber.nmt.edu