From: Nuno Silva <nuno.silva@vgertech.com>
To: Patryk Jakubowski <patrics@interia.pl>
Cc: linux-kernel@vger.kernel.org
Subject: Re: Invisible threads in 2.6.9
Date: Wed, 06 Oct 2004 04:08:12 +0100 [thread overview]
Message-ID: <4163619C.4070600@vgertech.com> (raw)
In-Reply-To: <41630B2C.5020709@interia.pl>
Patryk Jakubowski wrote:
...
> When I run it, the system (predictably) goes to ~100% CPU utilization,
> but there seems to be no way to find out who is hogging the CPU with
> top(1), ps(1), or anything else. All they can show is the main thread in
> zombie state, consuming 0% CPU.
>
> Is this correct behaviour of linux?
> Would not this allow user space programs to hide running executions?
> This could be an opportunity for spyware to infect the machine and hide
> itself perhaps? Hope I'm wrong here!
>
> If this is the bug in kernel (procfs?) I can give you my configuration
> and resulting behaviour.
Yes, that's the new method trojans are using to hide tasks... No need to
install complicated kernel modules anymore :-)
More seriously: That's a problem with current procps utils... They just
don't show them. I can't complain too much because I'm not doing any
code, but it would be nice to have a working top...
As a workaround, to at least see the threads without inspecting /proc
directly, you can use the 'm' and 'H' flags to ps, i.e.
$ ps auwxH
Regards,
Nuno Silva
next prev parent reply other threads:[~2004-10-06 3:08 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <S268296AbUJDTjb/20041004193948Z+2396@vger.kernel.org>
2004-10-05 20:59 ` Invisible threads in 2.6.9 Patryk Jakubowski
2004-10-06 3:08 ` Nuno Silva [this message]
2004-10-06 7:50 ` Michal Schmidt
2004-10-06 10:14 ` Patryk Jakubowski
[not found] ` <20041006110721.GC4380@vana.vc.cvut.cz>
2004-10-06 11:36 ` Patryk Jakubowski
2004-10-06 14:58 ` Chris Friesen
2004-10-07 0:21 Albert Cahalan
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