Strange TCP behaviour under 2.0.3x with accept

Philip Gladstone (philip@raptor.com)
Thu, 10 Sep 1998 10:10:23 -0400

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Hi,
It seems that under 2.0.3x series, if you do an
accept on an INET socket, you can get an incompletely formed
connection.

Assume the remote system sends a SYN.
The linux box responds with SYN-ACK and goes to state
SYN-RECV

After a while, the other end sends a reset which triggers
a state transition to TCP_CLOSE

TCP_CLOSE is a valid state to trigger the accept, and
so we get the call.

sys_accept doesn't check the return code from the
internal getpeername and returns OK rather than an
error (and it hasn't filled in the address).

I suspect that tcp_find_establish should have an extra condition

&& tcp_connected()

at the crucial point. Does anyone disagree?

Philip

-- 
Philip Gladstone                           +1 781 530 2461
Raptor Systems / Axent Technologies 
Waltham, MA         		    http://www.raptor.com/
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