Bug in ulimit ?

[David Peer <davidpeer@cs.huji.ac.il>]

Hi,


I'm using zsh 4.3.2-25 on debian, and noticed that when any user run: 
ulimit -t 0

from its shell, he manages to disable the cputime limitation if any.


for example:

I have a debian system that has cpu time limitation of 1 minute soft, 
and 2 minutes hard.

If the user run: ulimit -t 0, he can run jobs without any cputime 
limitation:


The soft limit:

<2|0>dib@mafalda:~> limit | grep cputime
cputime      1:00


The hard limit:

<5|0>dib@mafalda:~> ulimit -t unlimited

<6|0>dib@mafalda:~> limit | grep cputime

cputime      2:00


So far so good.

But:


<7|0>dib@mafalda:~> ulimit -t 0

<8|0>dib@mafalda:~> limit | grep cputime

cputime         0:00:00


Now the user can run processes without cpu time limitation.

You can see the output from "top" command, that it ran the job 
"testload" for more then 6 minutes.


4754 dib       30   5  1556  336  276 R 97.0  0.1   6:16.52 testload


Thanks in advanced,

David Peer.