Kernel Log "TCP: Treason uncloaked!"

Posted by hurikhan77 on Server Fault See other posts from Server Fault or by hurikhan77
Published on 2010-03-16T15:35:31Z Indexed on 2010/03/17 7:01 UTC
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Filed under:

linux

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kernel

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networking

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security

On one linux server (Gentoo hardened), we are experiencing bursts of the following messages in dmesg from time to time:

TCP: Treason uncloaked! Peer xx.xx.xxx.xxx:65039/80 shrinks window 4094157295:4094160199. Repaired.

Is there anything we should take care of or is this normal?

Update: Maybe related, we are using net.ipv4.tcp_congestion_control = cubic. Kernel version is 2.6.28 with Gentoo hardening patches.

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