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Date: Thu, 8 May 2014 06:59:22 +0000
From: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
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Subject: Re: [Qemu-devel] [PATCH,
 DoS] slirp (arp): do not special-case bogus IP addresses
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To: Samuel Thibault <samuel.thibault@gnu.org>
Cc: qemu-devel@nongnu.org

On Thu, May 08, 2014 at 08:50:33AM +0200, Samuel Thibault wrote:
> Edgar E. Iglesias, le Thu 08 May 2014 06:10:18 +0000, a écrit :
> > The search part looks OK to me but when adding to the arp table, don't
> > you at least want to avoid adding mappings for 0.0.0.0/32?
> 
> I don't see the gain, actually.  It would mean burning some CPU all the
> time just to save a small potential memory loss and CPU burning in the
> rare case when the guest behaves oddly.
> 
> > to avoid for ex garps to pollute the cache with invalid entries?
> 
> Only one entry will be created and updated by garps. The guest already
> has a lot of ways to pollute the cache :)

Hi,

I was under the impression that entries for 0.0.0.0 are strictly
invalid (not about performance). I might be wrong though.

Cheers,
Edgar