From owner-freebsd-questions  Tue Jan 14 04:29:53 1997
Return-Path: <owner-questions>
Received: (from root@localhost)
          by freefall.freebsd.org (8.8.4/8.8.4) id EAA10156
          for questions-outgoing; Tue, 14 Jan 1997 04:29:53 -0800 (PST)
Received: from Campino.Informatik.RWTH-Aachen.DE (campino.Informatik.RWTH-Aachen.DE [137.226.116.240])
          by freefall.freebsd.org (8.8.4/8.8.4) with ESMTP id EAA09925
          for <freebsd-questions@freefall.FreeBSD.org>; Tue, 14 Jan 1997 04:26:11 -0800 (PST)
Received: from gilberto.physik.rwth-aachen.de (gilberto.physik.rwth-aachen.de [137.226.31.2]) by Campino.Informatik.RWTH-Aachen.DE (RBI-Z-5/8.6.12)
	with ESMTP id NAA06087 for <freebsd-questions@freefall.FreeBSD.org>; Tue, 14 Jan 1997 13:28:24 +0100 (MET)
Received: (from kuku@localhost) by gilberto.physik.rwth-aachen.de (8.8.3/8.6.9) id NAA13072 for freebsd-questions@freefall.cdrom.com; Tue, 14 Jan 1997 13:27:01 +0100 (MET)
Date: Tue, 14 Jan 1997 13:27:01 +0100 (MET)
From: Christoph Kukulies <kuku@gilberto.physik.rwth-aachen.de>
Message-Id: <199701141227.NAA13072@gilberto.physik.rwth-aachen.de>
To: freebsd-questions@freefall.FreeBSD.org
Subject: NFS problem
Sender: owner-questions@FreeBSD.ORG
X-Loop: FreeBSD.org
Precedence: bulk


I have supplied a simple suid program doing a 
"system /sbin/mount -t cd9660 /dev/wcd0c /cdrom" on a 
2.2-BETA machine. The program is 

-rwsr-xr-x  1 root  bin  8808 Jan 14 13:12 /usr/local/bin/cdmount

(I left out nosuid,noexec considerations here for simpliness).


/etc/exports:

/usr -alldirs chuck hp
/ -alldirs gil blues hp
/cdrom gil blues hp

mounted is running -n (tried without also)

When I do the mount being su'ed everything works fine on the
client side.

Doing the mount with the suid program results in
mounting failure on the client side (hp-ux):

hp-ux # mount smile:/cdrom /mnt
mount: smile:/cdrom on /mnt: Permission denied

Mounting using the suid program I get (on the server):

smile # mount
miles> mount
/dev/wd0a on / (NFS exported, local)
/dev/wd0s3e on /usr (NFS exported, local)
/dev/wd0s1 on /c (local)
procfs on /proc (local)
/dev/wcd0c on /cdrom (local, read-only)

Looking at the mount type on the server side I get the following
picture in the case of mounting as 'su':

smile # mount
/dev/wd0a on / (NFS exported, local)
/dev/wd0s3e on /usr (NFS exported, local)
/dev/wd0s1 on /c (local)
procfs on /proc (local)
/dev/wcd0c on /cdrom (NFS exported, local, read-only)
                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

I'm baffled.

--Chris Christoph P. U. Kukulies kuku@gil.physik.rwth-aachen.de


Any clues?