topic Re: FTP-PROXY and Access Violation in Operating System - OpenVMS

FTP-PROXY and Access Violation

Russ Carraro — Wed, 16 Aug 2006 13:12:50 GMT

Customer replaced TCP/IP software (Pathway) with UCX 4.2 - ECO 5 on a VAX 7710 running OpenVMS 7.1. FTP commands
$ ftp
verbose on
open ftp-proxy
2410ftpupload@136.205.6.184
password
.
.
.

used to work but now return

ACED ON OR SENT OVER THIS SYSTEM MAY BE MONITORED. USE OF THI
230 User 2410ftpupload logged in.
%SYSTEM-F-ACCVIO, access violation, reason mask=01, virtual address=52502019, PC
=0004FD12, PSL=03C00000

Improperly handled condition, image exit forced.

Signal arguments Stack contents

Number = 00000005 00000000
Name = 0000000C 00000000
00000001 00000000
52502019 00000000
0004FD12 00000000
03C00000 00000000
00000000
00000000
00000000
00000000

Register dump

R0 = 52502045 R1 = 000047A2 R2 = 00002200 R3 = 00002200
R4 = 00000001 R5 = 7FFE5EBC R6 = 00000001 R7 = 00000001
R8 = 7FFECA48 R9 = 7FFECC50 R10= 7FFED7D4 R11= 7FFE2BDC
AP = 7FE3B340 FP = 7FE3B300 SP = 7FE3B37C PC = 0004FD12
PSL= 03C00000

Any thoughts on what the problem is and how to avoid it?

Re: FTP-PROXY and Access Violation

Steven Schweda — Wed, 16 Aug 2006 15:34:02 GMT

Go back to PathWay?

"SHOW SYMBOL FTP"? Any chance that you're
still running the PathWay FTP client?

"SHOW LOGICAL TWG$TCP"? It shouldn't be
defined now. (Nor "TWG$*", for that matter.)

Re: FTP-PROXY and Access Violation

Richard Whalen — Wed, 16 Aug 2006 15:34:34 GMT

Does it work to other IP addresses?
If so, I would guess that 136.205.6.184 is sending a 230 response that your FTP client can not handle.

Re: FTP-PROXY and Access Violation

John Gillings — Wed, 16 Aug 2006 18:43:50 GMT

Russ,

As you're no doubt aware, UCX is very old and well outside its support window.

That said, it's probably worth making sure you're up to date with whatever patches are available. For old stuff see http://ftp.hp.com.au/

I'm curious about the apparently chopped up message:

"ACED ON OR SENT OVER THIS SYSTEM MAY BE MONITORED. USE OF THI"

Is that a cut and paste artifact or verbatim? I assume it's a chunk of SYS$ANNOUNCE or SYS$WELCOME on the target system?

I also note that the ACCVIO address looks like a fragment of ASCII text ". PR" - could this also be a part of the same message?

If possible, it might be interesting to see what happens if the message is removed, or perhaps reduced in length.

On my systems, the ANONYMOUS account is set to:

DISWELCOME, DISNEWMAIL, DISMAIL, DISREPORT

This might be a clue telling us that the FTP client doesn't like extra messages on login. Perhaps you could get the ftpupload account on the target system set similarly?

Re: FTP-PROXY and Access Violation

Russ Carraro — Thu, 17 Aug 2006 06:49:33 GMT

The message is verbatim. I tried the FTP from a Vax/Alpha cluster and found out that it works from the Alpha but fails from the Vax. Cluster has a common SYSUAF.

Re: FTP-PROXY and Access Violation

Volker Halle — Thu, 17 Aug 2006 07:14:14 GMT

Russ,

note that the contents of R0 shown in the register output translates to an ASCII string 'E PR'.

Please try to connect to this FTP-proxy from some other node or operating system and/or try to get the full string of this message shown. Maybe it contains a substring 'E PR'. This would indicate, that the VAX UCX V4.2 ECO 5 (this is the most recent patch) FTP client cannot handle such a long message.

Maybe you can reduce the message size on your FTP-proxy server to work around this limitation.

Volker.

Re: FTP-PROXY and Access Violation

Russ Carraro — Tue, 29 Aug 2006 12:52:20 GMT

Works from Alphas so I had user log onto an Alpha instead of a Vax (mixed architecture cluster).