netdev - connect() sometimes succeeds when it shouldn't

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Date:	Thu, 18 Feb 2010 19:47:10 +0000
From:	Bruce Cran <bruce@...n.org.uk>
To:	netdev@...r.kernel.org
Subject: connect() sometimes succeeds when it shouldn't

Hi

I've found that if I run a program that does lots of calls to connect() then 
it will eventually succeed when there's no server listening. For SCTP it takes 
a few thousand, for TCP up to a couple of million.  I first came across the 
problem in Windows, where the connection was being processed so quickly that 
by the time the handler function had finished, the 'connecting' flag had 
already been reset, which wasn't expected. I've not checked the Linux sources 
to see if something similar is happening though.

The machine I tested it on was running a 2.6.32 i686 kernel.

The test code can be found at 
http://www.cran.org.uk/~brucec/linux/badconnect.c

-- 
Bruce Cran
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