2001-03-10 00:47:41

by Marco d'Itri

[permalink] [raw]
Subject: peer shrinks window

In two days I've got 46 messages like:

Mar 7 08:00:55 attila kernel: TCP: peer 163.162.41.4:37582/20 shrinks window 752789960:5840:752797200. Bad, what else can I say?

If needed I can ask about the os running there, I think it's solaris.
(nmap confirms: Solaris 7)

Linux attila 2.4.0-test11 #11 Wed Dec 13 12:02:51 CET 2000 ppc unknown

--
ciao,
Marco


2001-03-10 03:26:53

by Andres Salomon

[permalink] [raw]
Subject: Re: peer shrinks window

I've noticed this as well in my logs. In linux/include/net/tcp.h,
TCP_DEBUG is turned on; in linux/net/ipv4/tcp_input.c,
tcp_ack_update_window() contains the following:

#ifdef TCP_DEBUG
<snip>
printk(KERN_DEBUG "TCP: peer %u.%u.%u.%u:%u/%u shrinks window %u:%u:%u. Bad, what else can I say?\n",
NIPQUAD(sk->daddr), htons(sk->dport), sk->num,
tp->snd_una, tp->snd_wnd, tp->snd_nxt);
<snip>
#endif

Is it really necessary for TCP_DEBUG to be turned on by default?

On Sat, Mar 10, 2001 at 12:45:56AM +0100, Marco d'Itri wrote:
>
> In two days I've got 46 messages like:
>
> Mar 7 08:00:55 attila kernel: TCP: peer 163.162.41.4:37582/20 shrinks window 752789960:5840:752797200. Bad, what else can I say?
>
> If needed I can ask about the os running there, I think it's solaris.
> (nmap confirms: Solaris 7)
>
> Linux attila 2.4.0-test11 #11 Wed Dec 13 12:02:51 CET 2000 ppc unknown
>
> --
> ciao,
> Marco

--
"... being a Linux user is sort of like living in a house inhabited
by a large family of carpenters and architects. Every morning when
you wake up, the house is a little different. Maybe there is a new
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removed the floor under your bed." - Unix for Dummies, 2nd Edition
-- found in the .sig of Rob Riggs, [email protected]