[nos-bbs] FTP creates a wierd ftpd socket

(Skip) K8RRA k8rra at ameritech.net
Thu May 24 09:58:55 EDT 2007

Greetings to ftp users.

While using "ftp> resume file" command my jnos takes a wrong turn.
My ftp remote is IP / all is OK thru message #150 "Opening
data connection...".
FTP then tries to establish a new ftpd socket with IP.
This just will not work!

Now I can't totally blame jnos code for this - I have been *playing*
with all the tuning numbers for ax25, ip, tcp, and the TNC.  So I may be
my own worst nightmare.  

However this smells like a buffer overrun to me?

I don't have a clue where the IP came from.  The "tcp view" shows no
received or sent bytes, just retried bytes, therefore(?) the IP must be
created from a non-IP field.  Over the past two days, the IP number has
not varied...

Before you try to replicate this, it fails with "ftp> get file" too, and
until yesterday morning ftp behaved very nicely.  So I probably can fix
this by reverting to pre-yesterday configuration.

So my purpose here is to alert users to an unusual condition, and also
to provide a testbed if anyone wants to do debugging (I will eventually
find the parameter responsible for this mess)...

de [George (Skip) VerDuin] K8RRA k

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