I have just committed a fix for the "land" bug.  Here is the relevant
commit message:

thorpej
Thu Nov 20 22:18:32 PST 1997
Update of /cvsroot/src/sys/netinet
In directory netbsd1:/var/slash-tmp/cvs-serv14385

Modified Files:
        tcp_input.c 
Log Message:
In tcp_input(), if the PCB we lookup for an incoming packet is a listen
socket:
- If we received a SYN,ACK, send an RST.
- If we received a SYN, and the connection attempt appears to come from
  itself, send an RST, since it cannot possibly be valid.


This change has been pulled up to the NetBSD 1.3 release branch, and
will be available after the next supscan.

Please report any problems via send-pr(1) ASAP.

I will be posting a patch for NetBSD 1.2 (and 1.2.1) shortly.

Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                            Home: +1 408 866 1912
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