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Date: Thu, 22 Apr 2004 17:31:31 -0400 (EDT)
From: "Richard B. Johnson" <root@chaos.analogic.com>
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To: Agri <agri@desnol.ru>
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Subject: Re: BUG: fork do not copy /proc/<PID>/cmdline permissions
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On Fri, 23 Apr 2004, Agri wrote:

> On Thu, 22 Apr 2004 16:36:28 -0400 (EDT)
> "Richard B. Johnson" <root@chaos.analogic.com> wrote:
>
> > On Thu, 22 Apr 2004, Agri wrote:
> >
> > > I expected from fork to make a rather complete copy of a process,
> > > but it does not copy /proc/<PID>/cmdline access permissions.
> > > Therefore, the only way (at least i know) to hide all args of
> > > processes is to start every program within shell script:
> > > bash -c 'chmod /proc/$$/cmdline; exec userprogramm ...'
> > >
> > > Tested on 2.6.5.
> > >
> > > Agri
> >
> > Huh? /proc/$PID/cmdline doesn't exist until after a task is
> > created.
> So setting all /proc/$PID/* file parameters should be a part of task creation.
>

You didn't bother to read the line above nor the fact that /proc
has NOTHING TO DO WITH A PROCESS.

If you don't want to share information amongst tasks, you simply
execute `umount /proc` as root. Then nobody except root can see
anything about any other task if the home directories of other
tasks are not world readable.

Each task then becomes isolated in its own little cocoon.
[SNIPPED...]

Cheers,
Dick Johnson
Penguin : Linux version 2.4.26 on an i686 machine (5557.45 BogoMips).
            Note 96.31% of all statistics are fiction.