From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [net PATCH V2] net: fix divide by zero in tcp algorithm
 illinois
Date: Wed, 31 Oct 2012 18:14:38 +0100
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References: <20121031124318.30915.32293.stgit@dragon>
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Cc: "David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org,
	Petr Matousek <pmatouse@redhat.com>,
	Stephen Hemminger <shemminger@vyatta.com>
To: Jesper Dangaard Brouer <brouer@redhat.com>
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On Wed, 2012-10-31 at 13:45 +0100, Jesper Dangaard Brouer wrote:
> Reading TCP stats when using TCP Illinois congestion control algorithm
> can cause a divide by zero kernel oops.
> 
> The division by zero occur in tcp_illinois_info() at:
>  do_div(t, ca->cnt_rtt);
> where ca->cnt_rtt can become zero (when rtt_reset is called)
> 

> Cc: Petr Matousek <pmatouse@redhat.com>
> Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
> 
> ---

Acked-by: Eric Dumazet <edumazet@google.com>