CVS hangs on exit when using SSH

[Ken Williams]

Hi,

I've seen this problem several times in various CVS and SSH mailing 
lists, but none of the threads I've found seem to end in a solution.

I'm using CVS 1.10 `Halibut' as a client, connecting to CVS 1.11.2 on a 
server via SSH.  Both the client and server are running OpenSSH_3.4p1, 
SSH protocols 1.5/2.0, OpenSSL 0x0090605f.  The client is a Mac OS X 
10.1.5 machine and the server is running Red Hat Linux release 8.0.

When I issue any CVS command (update, checkout, diff, etc.), the 
connection hangs indefinitely when the command is [nearly?] completed.  
It happens reliably on this client, but never happens on another client 
with identical software versions.

When I set CVS_RSH to a shell script that does 'exec ssh -vvv "$@"', I 
get the following output (I hit Ctrl-C after about 30 seconds):

---------------------------------------------------------------------
% cvs up
OpenSSH_3.4p1, SSH protocols 1.5/2.0, OpenSSL 0x0090605f
debug1: Reading configuration data /etc/ssh_config
debug1: Rhosts Authentication disabled, originating port will not be 
trusted.
debug1: ssh_connect: needpriv 0
debug1: Connecting to ebt.ee.usyd.edu.au [129.78.13.247] port 22.
debug1: Connection established.
debug1: identity file /Users/ken/.ssh/identity type 0
debug3: Not a RSA1 key file /Users/ken/.ssh/id_rsa.
debug2: key_type_from_name: unknown key type '-----BEGIN'
debug3: key_read: no key found
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug2: key_type_from_name: unknown key type '-----END'
debug3: key_read: no key found
debug1: identity file /Users/ken/.ssh/id_rsa type 1
debug3: Not a RSA1 key file /Users/ken/.ssh/id_dsa.
debug2: key_type_from_name: unknown key type '-----BEGIN'
debug3: key_read: no key found
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug3: key_read: no space
debug2: key_type_from_name: unknown key type '-----END'
debug3: key_read: no key found
debug1: identity file /Users/ken/.ssh/id_dsa type 2
debug1: Remote protocol version 1.99, remote software version 
OpenSSH_3.4p1
debug1: match: OpenSSH_3.4p1 pat OpenSSH*
Enabling compatibility mode for protocol 2.0
debug1: Local version string SSH-2.0-OpenSSH_3.4p1
debug1: SSH2_MSG_KEXINIT sent
debug1: SSH2_MSG_KEXINIT received
debug2: kex_parse_kexinit: diffie-hellman-group-exchange-
sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-
cbc,cast128-cbc,arcfour,aes192-cbc,aes256-cbc,address@hidden
debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-
cbc,cast128-cbc,arcfour,aes192-cbc,aes256-cbc,address@hidden
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-
ripemd160,address@hidden,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-
ripemd160,address@hidden,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none
debug2: kex_parse_kexinit: none
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: kex_parse_kexinit: diffie-hellman-group-exchange-
sha1,diffie-hellman-group1-sha1
debug2: kex_parse_kexinit: ssh-rsa,ssh-dss
debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-
cbc,cast128-cbc,arcfour,aes192-cbc,aes256-cbc,address@hidden
debug2: kex_parse_kexinit: aes128-cbc,3des-cbc,blowfish-
cbc,cast128-cbc,arcfour,aes192-cbc,aes256-cbc,address@hidden
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-
ripemd160,address@hidden,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: hmac-md5,hmac-sha1,hmac-
ripemd160,address@hidden,hmac-sha1-96,hmac-md5-96
debug2: kex_parse_kexinit: none,zlib
debug2: kex_parse_kexinit: none,zlib
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit:
debug2: kex_parse_kexinit: first_kex_follows 0
debug2: kex_parse_kexinit: reserved 0
debug2: mac_init: found hmac-md5
debug1: kex: server->client aes128-cbc hmac-md5 none
debug2: mac_init: found hmac-md5
debug1: kex: client->server aes128-cbc hmac-md5 none
debug1: SSH2_MSG_KEX_DH_GEX_REQUEST sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_GROUP
debug1: dh_gen_key: priv key bits set: 135/256
debug1: bits set: 1567/3191
debug1: SSH2_MSG_KEX_DH_GEX_INIT sent
debug1: expecting SSH2_MSG_KEX_DH_GEX_REPLY
debug3: check_host_in_hostfile: filename /Users/ken/.ssh/known_hosts2
debug3: check_host_in_hostfile: filename /etc/ssh_known_hosts2
debug3: check_host_in_hostfile: filename /Users/ken/.ssh/known_hosts2
debug3: check_host_in_hostfile: filename /etc/ssh_known_hosts2
debug3: check_host_in_hostfile: filename /Users/ken/.ssh/known_hosts
debug3: key_read: type mismatch
debug3: check_host_in_hostfile: match line 18
debug3: check_host_in_hostfile: filename /Users/ken/.ssh/known_hosts
debug3: key_read: type mismatch
debug3: check_host_in_hostfile: match line 18
debug1: Host 'ebt.ee.usyd.edu.au' is known and matches the RSA host key.
debug1: Found key in /Users/ken/.ssh/known_hosts:18
debug1: bits set: 1618/3191
debug1: ssh_rsa_verify: signature correct
debug1: kex_derive_keys
debug1: newkeys: mode 1
debug1: SSH2_MSG_NEWKEYS sent
debug1: waiting for SSH2_MSG_NEWKEYS
debug1: newkeys: mode 0
debug1: SSH2_MSG_NEWKEYS received
debug1: done: ssh_kex2.
debug1: send SSH2_MSG_SERVICE_REQUEST
debug1: service_accept: ssh-userauth
debug1: got SSH2_MSG_SERVICE_ACCEPT
debug1: authentications that can continue: 
publickey,password,keyboard-interactive
debug3: start over, passed a different list 
publickey,password,keyboard-interactive
debug3: preferred publickey,keyboard-interactive,password
debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: next auth method to try is publickey
debug1: try pubkey: /Users/ken/.ssh/id_rsa
debug3: send_pubkey_test
debug2: we sent a publickey packet, wait for reply
debug1: input_userauth_pk_ok: pkalg ssh-rsa blen 149 lastkey 0x4ebc0 
hint 1
debug2: input_userauth_pk_ok: fp 
74:af:ca:bc:71:e3:45:08:c5:32:31:de:98:25:23:8a
debug3: sign_and_send_pubkey
debug1: read PEM private key done: type RSA
debug1: ssh-userauth2 successful: method publickey
debug1: fd 5 setting O_NONBLOCK
debug1: fd 7 setting O_NONBLOCK
debug1: channel 0: new [client-session]
debug3: ssh_session2_open: channel_new: 0
debug1: send channel open 0
debug1: Entering interactive session.
debug2: callback start
debug1: ssh_session2_setup: id 0
debug1: Sending command: cvs server
debug1: channel request 0: exec
debug2: callback done
debug1: channel 0: open confirm rwindow 0 rmax 32768
debug2: channel 0: rcvd adjust 131072
? results
? results-drmath.txt
? results-reuters.txt
? tmon.out
? tree-spam.png
? corpora/20news-18827.tar.gz
? corpora/drmath-1.00-small
? corpora/drmath-1.00-small.tgz
? corpora/drmath-NBB-results.txt
? corpora/drmath-NBB-results2.txt
? corpora/drmath-results.txt
? corpora/reuters-results.txt
? doc/aptemod.xls
? doc/Corpora-new.xls
? doc/current_design.graffle
? doc/data-model.graffle
? doc/drmath-run.xls
? doc/Framework-PSD.txt
? doc/inheritance-uml.dot
? doc/position-bias.xls
? doc/proposed_design.graffle
? doc/ADCS-SignalG/sr-save.pdf
? doc/ADCS-SignalG/TC-References.bib
? doc/Thesis/figures/diagram-key.graffle
? doc/Thesis/figures/inheritance-uml.graffle
? experiments/drmath-small-NB.yaml
? ref/ktrace.out
? ref/Tumer-Ghosh-1996.ps
? tools/out.dot
? tools/out.png
? tools/scan.pl
M doc/Thesis/ch01.tex
M doc/Thesis/ch02.tex
M doc/Thesis/ch03.tex
M doc/Thesis/ch05.tex
M tools/scan_classes.pl
^Ccvs [update aborted]: received interrupt signal
debug1: channel_free: channel 0: client-session, nchannels 1
debug3: channel_free: status: The following connections are open:
  #0 client-session (t4 r0 i0/0 o0/0 fd 5/7)

debug3: channel_close_fds: channel 0: r 5 w 7 e 8
debug1: fd 0 clearing O_NONBLOCK
debug1: fd 1 clearing O_NONBLOCK
Killed by signal 2.
debug1: Calling cleanup 0xdf14(0x0)
debug1: Calling cleanup 0x18188(0x0)
%
---------------------------------------------------------------------

Any help?

 -Ken