Nice trace of another 2.2 TCP bug

Alan Cox (alan@lxorguk.ukuu.org.uk)
Tue, 16 Mar 1999 22:49:50 +0000 (GMT)

> Netscape says: 'Connect: Host www.skandiabanken.se contacted. Waiting
> for reply...' and then nothing more happens. Lynx says 'HTTP request
> sent; waiting for response.'.
>
> Can anybody confirm this problem? Any ideas what the cause is?

Linux tcp bug. Quite clear

21:53:10.518536 roadrunner.3259 > 194.103.154.226.http: S 3990558226:3990558226(0) win 32120 <mss 1460,sackOK,timestamp 54264856[|tcp]> (DF)
21:53:11.011195 194.103.154.226.http > roadrunner.3259: S 2269188722:2269188722(0) ack 3990558227 win 0

They reply to our connection with a zero window - weird but legal

21:53:11.011254 roadrunner.3259 > 194.103.154.226.http: . ack 1 win 32120 (DF)
21:53:11.012305 roadrunner.3259 > 194.103.154.226.http: . ack 1 win 32120 (DF)

We probe it

21:53:11.271268 194.103.154.226.http > roadrunner.3259: . ack 1 win 8760

They open the window

21:53:11.271333 roadrunner.3259 > 194.103.154.226.http: . ack 1 win 32120 (DF)
21:53:13.538118 roadrunner.3259 > 194.103.154.226.http: . ack 1 win 32120 (DF)
21:53:18.078118 roadrunner.3259 > 194.103.154.226.http: . ack 1 win 32120 (DF)

We forget to send any data

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/