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Subject: [Bug 217637] One TCP connection accepted TWO times
Date: Fri, 17 Mar 2017 01:42:44 +0000
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D217637

--- Comment #21 from Sepherosa Ziehau <sepherosa@gmail.com> ---
(In reply to Michael Tuexen from comment #18)

Hmm, do any OS's TCP stacks really send data along w/ the last ACK in the 3=
-way
handshake at all?

And if we are checking the syncookie, it indicates we suffered short-of-mem=
ory
previously.  I don't think we need to record that situation.

Let me rephrase my original suggestion (I am not a native speaker, sorry):
Drop the last ACK w/ data, before syncookie is going to be checked.

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