openssh unix dev - Mar 2003 - AIX 4.3.3/OpenSSH 3.5p1 Crashing

I'm getting core dumps from sshd when logging in using password
authentication (using a public key works just fine). The core dump occurs
just after entering a password--whether that password is correct or not. It
only happens on this one machine. I've tried recompiling the entire
setup--zlib, openssl & openssh--and the crash still occurs. It doesn't
look
like the putty-failure issue discussed in the archives, although it may be
related. Anyone have any ideas?

This is what it looks like from the client side:

[ruhl at pstrain ruhl]$ ssh -p 1212 localhost
ruhl at localhost's password:
Connection closed by 127.0.0.1
[ruhl at pstrain ruhl]$

And this from the server side:

debug3: mm_request_send entering: type 10
debug3: monitor_read: checking request 10
debug3: mm_answer_authpassword: sending result 0
debug3: mm_request_send entering: type 11
debug3: mm_auth_password: waiting for MONITOR_ANS_AUTHPASSWORDFailed none
for ruhl from 127.0.0.1 port 63536 ssh2
debug3: mm_request_receive entering

debug3: mm_request_receive_expect entering: type 11
debug3: mm_request_receive entering
debug3: mm_auth_password: user not authenticated
Failed none for ruhl from 127.0.0.1 port 63536 ssh2
debug1: userauth-request for user ruhl service ssh-connection method
password
debug1: attempt 1 failures 1
debug2: input_userauth_request: try method password
debug3: mm_auth_password entering
debug3: mm_request_send entering: type 10
debug3: monitor_read: checking request 10
debug3: mm_auth_password: waiting for MONITOR_ANS_AUTHPASSWORD
debug3: mm_request_receive_expect entering: type 11
debug3: mm_request_receive entering
debug1: Calling cleanup 0x2000f0f4(0x0)
Segmentation fault (core dumped)

--
Robert Uhl
IBM Global Services @ CoBank
303.694.5882
uhlr at us.ibm.com

Robert A Uhl wrote:
> I'm getting core dumps from sshd when logging in using password
> authentication (using a public key works just fine). The core dump occurs
> just after entering a password--whether that password is correct or not. It
> only happens on this one machine. I've tried recompiling the entire
> setup--zlib, openssl & openssh--and the crash still occurs. It
doesn't look
> like the putty-failure issue discussed in the archives, although it may be
> related. Anyone have any ideas?
The core dump might be caused by the fatal_cleanup bug (can't get on to
bugzilla right now, but the patch for it is below).  If so, the core
dump is not the cause of your authentication problem (but might be
triggered by it).

The other thing you can do is to get a backtrace to show exactly where
the failure is ocurring, eg:

# gdb ./sshd core
(gdb) backtrace

		-Daz.

Index: log.c
==================================================================RCS file:
/cvs/openssh/log.c,v
retrieving revision 1.26
retrieving revision 1.27
diff -u -r1.26 -r1.27
--- log.c       7 Jan 2003 06:04:18 -0000       1.26
+++ log.c       14 Jan 2003 11:22:43 -0000      1.27
@@ -233,6 +233,7 @@
                next_cu = cu->next;
                xfree(cu);
        }
+       fatal_cleanups = NULL;
 }
 
 /* Cleanup and exit */

-- 
Darren Tucker (dtucker at zip.com.au)
GPG Fingerprint D9A3 86E9 7EEE AF4B B2D4  37C9 C982 80C7 8FF4 FA69
    Good judgement comes with experience. Unfortunately, the experience
usually comes from bad judgement.