[gPXE-devel] [tcp] Fix error ACK number in FIN packet.

[Guo-Fu Tseng]

On Wed, 19 May 2010 11:44:09 +0100, Michael Brown wrote
> On Wednesday 19 May 2010 11:16:51 Guo-Fu Tseng wrote:
> >     In recent TCP stack testing, I've found that the FIN packet is
> >  in-correct while downloading with HTTP. The attach shows the data before
> >  and after this is fixed.
> 
> Nice catch.  It's probably neater to move the call to tcp_rx_seq() 
> above the call to xfer_deliver_iob(), rather than using a hack to work 
> around the problem.
> 
> A consequence of making this change is that you would then have to 
> treat xfer_deliver_iob() errors as fatal to the connection, but that's 
> arguably a good idea anyway.
> 
> Michael
Actually, I did consider to send a patch like exactly what you said. :)

The reason I choose to send this one is it seems to me that letting
rx path complete it's job in normal flow would make it easier to
understand.

And the condition in tcp_xfer_close() can be seen as called by upperlayer
due to receive complete, or by the upplayer actively wants to turn down
the connection.

However, I totally agree this is a workarround, and there should be
a better way to fix it. I'll see if any good idea comes to my mind.

If someone have idea about how to fix it would help me a lot. :)

Guo-Fu Tseng