Re: luser beeing able to kill random root owned procs (linux 2.2.20) ?

From: rpc (rpcat_private)
Date: Fri Nov 09 2001 - 16:55:52 PST

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    On Wed, 1 Jan 1997, Ralf Dreibrodt wrote:
    
    > Hi,
    >
    > >while running "vi `perl -e 'print "." x 90000000'`" on
    > >a 2.2.20 linux kernel as a normal user, I've noticed:
    > >
    > >forsaken:~$ dmesg
    > >VM: killing process snmpd
    > >forsaken:~$ uname -rs
    > >Linux 2.2.20
    > >
    > >snmpd was running as root (this machine has 64MBytes of RAM)
    >
    >
    > the user is not allowed to kill a process owned by root, the user is allowed
    > to use all RAM (and probably swap).
    >
    > you can test whether he is allowed to and what will happen, when you execute
    > something like this:
    >
    > while true; do temp=$(echo temp$temp$temp$temp); done
    
    No, this is an artifact of Rik van Riel's OOM (out of memory) Kill code of
    the linux VM. When system resources are low, a process is chosen with a
    'badness' algorithm (oom_kill.c in the kernel source tree).
    
    Obviously, the code still needs more tweaking.
    --rpc
    
    
    >
    > bye
    > Ralf
    >
    >
    



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