[Bug] Corrupted download data

[IOftpd_USER]

I have strange problem - I have ftp box with Win XP SP3, no firewall, no antivirus and sometimes (randomly), when I download data from that box, data are corrupted. I found out, that file is bigger then it should be.

For example:
Correct file has 20*000*000 bytes, downloaded file 20*001*460 bytes. When I compare these two files, I can see there is three empty lines:
http://img142.imageshack.us/img142/9933/20090804145228.png

Logs:
Debug:
08-04-2009 08:45:45 Created TCL Interpreter #1
08-04-2009 08:45:45 Created TCL Interpreter #2
08-04-2009 08:45:45 Created TCL Interpreter #3
08-04-2009 08:45:56 Created TCL Interpreter #4
08-04-2009 08:46:04 Created TCL Interpreter #5
08-04-2009 08:49:10 Marked for deletion TCL Interpreter #1
08-04-2009 08:49:10 Deleting TCL Interpreter #1
08-04-2009 08:49:10 Finalizing TCL Interpreter #1 for thread 956
08-04-2009 08:49:10 Created TCL Interpreter #6
08-04-2009 08:49:11 Marked for deletion TCL Interpreter #5
08-04-2009 08:49:11 Deleting TCL Interpreter #5
08-04-2009 08:49:11 Finalizing TCL Interpreter #5 for thread 1688
08-04-2009 08:49:11 Created TCL Interpreter #7
08-04-2009 08:49:11 Marked for deletion TCL Interpreter #3
08-04-2009 08:49:11 Deleting TCL Interpreter #3
08-04-2009 08:49:11 Finalizing TCL Interpreter #3 for thread 1676
08-04-2009 08:49:11 Created TCL Interpreter #8
08-04-2009 08:49:17 Marked for deletion TCL Interpreter #4
08-04-2009 08:49:17 Deleting TCL Interpreter #4
08-04-2009 08:49:17 Finalizing TCL Interpreter #4 for thread 1580
08-04-2009 08:49:17 Created TCL Interpreter #9
08-04-2009 08:49:30 Marked for deletion TCL Interpreter #2
08-04-2009 08:49:30 Deleting TCL Interpreter #2
08-04-2009 08:49:30 Finalizing TCL Interpreter #2 for thread 1680
08-04-2009 08:49:30 Created TCL Interpreter #10
08-04-2009 09:00:16 Created TCL Interpreter #1
08-04-2009 09:00:16 Created TCL Interpreter #2
08-04-2009 09:00:18 Created TCL Interpreter #3
08-04-2009 09:00:18 Created TCL Interpreter #4
08-04-2009 09:00:26 Created TCL Interpreter #5


Error:
07-29-2009 16:32:22 AcceptEx() failed with error: 64
07-29-2009 16:32:22 AcceptEx() failed with error: 64
07-29-2009 16:32:22 AcceptEx() failed with error: 64
07-29-2009 16:32:22 AcceptEx() failed with error: 121
07-29-2009 16:32:22 AcceptEx() failed with error: 121
07-29-2009 16:32:22 AcceptEx() failed with error: 64
07-29-2009 16:32:57 AcceptEx() failed with error: 121
07-29-2009 16:32:57 AcceptEx() failed with error: 121
07-29-2009 16:32:57 AcceptEx() failed with error: 121
07-29-2009 16:32:57 AcceptEx() failed with error: 121
07-29-2009 16:32:57 AcceptEx() failed with error: 121
07-29-2009 16:32:57 AcceptEx() failed with error: 121
07-29-2009 16:32:57 AcceptEx() failed with error: 121
07-29-2009 16:33:29 AcceptEx() failed with error: 121
07-29-2009 16:33:29 AcceptEx() failed with error: 121
07-29-2009 16:33:29 AcceptEx() failed with error: 121
07-29-2009 16:33:29 AcceptEx() failed with error: 121
07-29-2009 16:33:29 AcceptEx() failed with error: 121
07-29-2009 16:33:29 AcceptEx() failed with error: 121
07-29-2009 16:33:29 AcceptEx() failed with error: 121
07-29-2009 16:33:42 AcceptEx() failed with error: 121
07-29-2009 16:33:42 AcceptEx() failed with error: 121
07-29-2009 16:33:42 AcceptEx() failed with error: 64
07-29-2009 16:33:42 AcceptEx() failed with error: 64
07-29-2009 16:33:42 AcceptEx() failed with error: 64
07-29-2009 16:33:42 AcceptEx() failed with error: 121
07-29-2009 16:33:42 AcceptEx() failed with error: 64


xferlog is showing this file with no difference then the others.

When I re-download file manualy, it is usually ok. What can cause this?

[Yil]

Bigger is weird. Very weird. What client are you using when you see this problem? Is it trying to do something fancy like use multiple connections to download the file (which means it's more likely a client issue). Did it try to resume the transfer the first time because of a broken connection? If so, how far does did it rollback if any? Binary mode used? ioFTPD sort of ignore binary/ascii since there isn't any translation going on but a client could confuse that on a reconnect or something and misjudge where to pickup the transfer.

[IOftpd_USER]

I was using ioFTPd v6.9.3. I upgraded last night, so I will keep testing and let you know the result.
Your questions:
1) Client - Total Commander v7.04a.
2) No multiple transfers.
3) No error, transfer was not broken and was not reconnected. I am not sure if resume fixes it.
4) Auto mode used.

[Yil]

See if you can reproduce this problem using a different FTP client. It's entirely possible this is an ioFTPD bug, but given the perhaps hundreds of TBs transferred via ioFTPD v6.9.3 I haven't heard of other corruption issue problems. A lot of that would have been rar/sfv which should have caught that kind of thing. For you to see this problem often enough that you noticed it seems odd to me. Given the non-common FTP client see if you can get it to happen with a trial of Flash/Rush/etc just to rule the client out.