[lwip-users] Patch for bug 23119

[Ken Smith]

I'm using lwip-1.3.0 and I believe I have encountered the problem
discussed here.

http://savannah.nongnu.org/bugs/?23119

I am using SO_RCVTIMEO (set to 30 seconds) and occasionally, my
application gets into a loop where lwip with TCP_DEBUG enabled just
keeps displaying:

tcp_slowtmr: processing active pcb
tcp_slowtmr: max SYN retries reached
tcp_pcb_purge
tcp_pcb_purge: data left on ->unacked

I have not been able to reproduce the issue deterministically.  I
think it depends on data that my peer is sending me.  I would like to
do some testing after applying the patch attached to this bug report,
lwip.bug23119.2.patch.  When I do

patch -p0 < lwip.bug23119.2.patch

in my lwip-1.3.0 directory, it claims the patch has already been
applied, it says:

Reversed (or previously applied) patch detected!  Assume -R? [n]

And, after looking at the patch, I agree that applying it forward
would get me what I already have.  The date for this patch is May 2008
which is after the 1.3.0 release of lwip in March that year.  Do I
need to apply this patch in reverse to get this bugfix?

    Regards,
    Ken