From mboxrd@z Thu Jan  1 00:00:00 1970
From: LC Bruzenak <lenny@magitekltd.com>
Subject: Re: user message limits
Date: Mon, 08 Jun 2009 17:08:33 -0500
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	<200901281215.16996.sgrubb@redhat.com>
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To: Steve Grubb <sgrubb@redhat.com>
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On Wed, 2009-01-28 at 12:15 -0500, Steve Grubb wrote:
> On Tuesday 27 January 2009 07:01:08 pm LC Bruzenak wrote:
> > Even when I get a successful return value (from audit_log_user_message),
> > I don't get my string back out in "ausearch" unless it is WAY smaller -
> > ~1K or less I think.
> >
> > Any ideas/thoughts?
> 
> I tested like this:
> 
> auditctl -m `perl -e '{print "A"x"2048"}'`
> 
> and found its getting cutoff just under 1K. So, I checked the kernel code and 
> found this:
> 
>  761                        if (msg_type != AUDIT_USER_TTY)
>  762                                audit_log_format(ab, " msg='%.1024s'",
>  763                                                 (char *)data);
>  764                        else {
> 
> Offhand, I don't remember why the kernel sets the limit so low. It could be 
> bumped some. How much, I don't know. 4K or 8K would seem fine.
> 
> -Steve

I apologize in advance, but I've lost the bubble on input event length. 
Is there a plan for the kernel to allow bigger buffers in to be audited?

As of my current one (2.6.29.4-75.fc10) I'm still in the same ~900 byte
range. 

To me, it seems that an increase would be automatically
backward-compatible. The "dropoff" point would just extend out a ways...

Thx,
LCB.

-- 
LC (Lenny) Bruzenak
lenny@magitekltd.com