scp client hangs after authentication with dropbear server

[Steven Hein]

Steven Hein wrote:

> I have the dropbear server running on a PPC-based embedded board.
> I can ssh into it just fine.   But when I try to scp to or from
> this dropbear server (using an openssh scp client, that's the only
> one I've tried), it hangs after successful authentication with
> a password.
>
>
> On the client side:
> 1236$ scp root at essc1:/tmp/test /tmp
> root at essc1's password:
> <hangs here>
>
> On the dropbear server side (running dropbear -F -E):
> [103] Jan 01 00:16:12 Child connection from 137.38.228.162:41937
> [103] Jan 01 00:16:14 password auth succeeded for 'root' from 
> 137.38.228.162:41937
> <no more output, until I CTRL-C the scp client, then I see...>
> [103] Jan 01 00:18:10 exit after auth (root): Exited normally
>
>
> What am I doing wrong?    I've tried 0.47 and 0.48.1, with the
> same results.   I'm doing a generic build, nothing disabled, and no
> multi-binary build.
>
> Any help would be greatly appreciated!
>
> Thanks, Steve
>
A few more details:

* scp does not get/send the file at all (so it is different from the
  Oct '06 report of an scp hang where the file was actually transferred)
* the dropbear process for this scp is sleeping (no cpu usage)
* I get the same results if I start dropbear standalone or from inetd
* strace of the dropbear process shows it stuck on a select() after
  authentication (with an occasional gettimeofday() call).

Any ideas would be very helpful, thanks!

-- 
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Steve Hein (ssh at sgi.com)              Engineering Diagnostics/Software
Silicon Graphics, Inc.                          
1168 Industrial Blvd.                 Phone: (715) 726-8410
Chippewa Falls, WI 54729              Fax:   (715) 726-6715
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