[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Can't get the set-user-id bit to work
From: |
Sebastian Tennant |
Subject: |
Can't get the set-user-id bit to work |
Date: |
Tue, 27 Dec 2005 16:55:17 +0000 |
User-agent: |
Gnus/5.110004 (No Gnus v0.4) Emacs/21.4 (gnu/linux) |
Hi all,
If it's a festive time of year where you are then I hope you're
enjoying it.
First of all, apologies if this is not the correct list for this
query. Perhaps you could suggest where else I should go.
I have a 3-line script; foo:
#!/bin/bash
id -u # EUID
id -u -r # `real' UID
Here's it's directory listing:
-rwsrwxr-- 1 root adm 1317 Dec 27 16:18 foo
I set these permissions with the command:
$ sudo chmod 4774 foo
Here's what I get if I run foo as myself (UID 1000):
$ ./foo
1000
1000
Surely this should be:
$ ./foo
0
1000
... or am I missing the point somehow?
I started to investigate the behaviour of the set-user-id bit because
of another problem I've been experiencing for some time:
A cron.daily script handles mandb. I elected to install it with the
set-user-id bit set, as you can see:
/usr/lib/man-db:
used 220 available 573264
drwxr-xr-x 2 root root 4096 Oct 16 15:13 .
drwxr-xr-x 116 root root 24576 Dec 14 11:49 ..
-rwsr-xr-x 1 man root 86932 Sep 21 13:23 man
-rwsr-xr-x 1 man root 96808 Sep 21 13:23 mandb
Every day I receive the same message in my inbox:
/etc/cron.daily/man-db script:
mandb: can't create a temporary filename: Permission denied
mandb is a binary executable file so I have no idea where it is trying
to create the temporary file, but it certianly shouldn't have any
trouble creating it in /tmp:
drwxrwxr-x 13 root root 4096 Dec 27 16:50 /tmp
Any help with either of these issues is very much appreciated.
sdt
--
GNU bash, version 3.1.0(1)-release (i486-pc-linux-gnu)
Copyright (C) 2005 Free Software Foundation, Inc.