On Thu, 2011-09-29 at 14:14 -0500, Michael B. Brutman wrote: > Interesting bug. I thought that this would be an easy catch, but it is > more subtle than I thought. I can't recreate it here. > > Your client sends a PASV command before attempting to put the file, > which is the correct behavior. Under normal circumstances that just > tells the server to start listening on port for an incoming connection > from your client. If a PORT command or another PASV command is issued > that listening socket gets tossed away. > > In this case it is behaving like your client actually started connecting > on that socket, or even connected. So there is an open data connection > but no data flowing. And the next command (the dir or ls) requires a > data connection, but it can't just blast the existing one. Hence the > error message. > > I'm not sure what's going on, but I suspect that after about 10 seconds > it would go away if it was just a connection that was starting. At > worst case that session is hosed up until that user logs out. > > I'm going to keep looking at it, but it's not obvious. It's also > probably been in the code since day one - you just got lucky enough to > hit it.
In case you want to replicate it on Linux, it's part of the netkit (http://www.hcs.harvard.edu/~dholland/computers/netkit.html) distribution, release 0.17. It's one of the oldest ftp clients out there. -- Tactical Nuclear Kittens ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity and more. Splunk takes this data and makes sense of it. Business sense. IT sense. Common sense. http://p.sf.net/sfu/splunk-d2dcopy1 _______________________________________________ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
