From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next-2.6] ipv4: Fix PMTU update.
Date: Sun, 13 Mar 2011 18:38:45 -0700 (PDT)
Message-ID: <20110313.183845.226774350.davem@davemloft.net>
References: <20110310150958.123c9f7f.shimoda.hiroaki@gmail.com>
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From: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>
Date: Thu, 10 Mar 2011 15:09:58 +0900

> On current net-next-2.6, when Linux receives ICMP Type: 3, Code: 4
> (Destination unreachable (Fragmentation needed)), 
> 
>   icmp_unreach
>     -> ip_rt_frag_needed
>          (peer->pmtu_expires is set here)
>     -> tcp_v4_err
>          -> do_pmtu_discovery
>               -> ip_rt_update_pmtu
>                    (peer->pmtu_expires is already set,
>                     so check_peer_pmtu is skipped.)
>                    -> check_peer_pmtu
> 
> check_peer_pmtu is skipped and MTU is not updated.
> 
> To fix this, let check_peer_pmtu execute unconditionally.
> And some minor fixes
> 1) Avoid potential peer->pmtu_expires set to be zero.
> 2) In check_peer_pmtu, argument of time_before is reversed.
> 3) check_peer_pmtu expects peer->pmtu_orig is initialized as zero,
>    but not initialized.
> 
> Signed-off-by: Hiroaki SHIMODA <shimoda.hiroaki@gmail.com>

This looks great, thanks for fixing this bug.

Applied.