cvs client interacting with a 1.12.13 server sometimes hangs indefinitely

[Bulgrien, Kevin]

An FYI that might help someone else:

After a production cvs server was updated from Mandriva Corporate Server 4.0
to Mandriva Enterprise Server 5.1, the CVS server version bumped up from
1.11.x to 1.12.13.

  Concurrent Versions System (CVS) 1.12.13 (client/server)

After this update, a cvs client that is quite heavily used on Windows systems
started to hang on various operations.  (Apparently a number of different
cvs clients are affected.)

Before the root cause was found, it seemed possible to log on to the server
and look to see if the user's cvs process was still using CPU time.  Upon
confirming that their appeared to be no client/server communication going on,
using ^C on the client seemed to leave the CVS sandbox intact.

At first it seemed the problem mostly occurred when large files were involved,
but it is not clear that large files have to be involved for this to happen.
Eventually a bit of web searching lead to a WANdisco publication that led to

  bug #14840: zlib.c implementation in 1.12.12+ still broken
  https://savannah.nongnu.org/bugs/?func=detailitem&item_id=14840

It appears that the bug is server-side rather than client-side.  It was fixed
in 2005, and a fix will ship if/when 1.12.14 is released.  Until then, it
seems the options for avoiding the issue include reverting the server to
one older than 1.12.12, or by building a new/patched one.

---
Kevin R. Bulgrien
Design and Development Engineer

This message and/or attachments may include information subject to GD Corporate 
Policy 07-105 and is intended to be accessed only by authorized personnel of 
General Dynamics and approved service providers.  Use, storage and transmission 
are governed by General Dynamics and its policies. Contractual restrictions 
apply to third parties.  Recipients should refer to the policies or contract to 
determine proper handling.  Unauthorized review, use, disclosure or 
distribution is prohibited.  If you are not an intended recipient, please 
contact the sender and destroy all copies of the original message.