Ticket History #555: telnetd segv's if /etc/krb5.conf doesn't exist

From marty@caltrans.ca.gov Wed Mar 4 15:59:36 1998
Received: from MIT.EDU (PACIFIC-CARRIER-ANNEX.MIT.EDU [18.69.0.28]) by rt-11.MIT.EDU (8.7.5/8.7.3) with SMTP id PAA28448 for <bugs@RT-11.MIT.EDU>; Wed, 4 Mar 1998 15:59:35 -0500
Received: from dns.caltrans.ca.gov by MIT.EDU with SMTP
id AA07475; Wed, 4 Mar 98 15:59:59 EST
Received: from db1.caltrans.ca.gov by caltrans.ca.gov (SMI-8.6/SMI-SVR4)
id MAA20872; Wed, 4 Mar 1998 12:53:18 -0800
Received: by db1.caltrans.ca.gov (SMI-8.6/SMI-SVR4)
id MAA23677; Wed, 4 Mar 1998 12:59:15 -0800
Message-Id: <199803042059.MAA23677@db1.caltrans.ca.gov>
Date: Wed, 4 Mar 1998 12:59:15 -0800
From: marty@caltrans.ca.gov
Reply-To: marty@caltrans.ca.gov
To: krb5-bugs@MIT.EDU
Cc: marty@db1.caltrans.ca.gov
Subject: telnetd segv's if /etc/krb5.conf doesn't exist
X-Send-Pr-Version: 3.99

Caltrans


System: SunOS db1 5.5.1 Generic sun4u sparc SUNW,Ultra-Enterprise
Architecture: sun4


If /etc/inetd.conf is modified to launch /usr/local/sbin/telnetd
for incoming telnet connections and /etc/krb5.conf does not exist,
it is not possible to telnet to the host.

# mv /etc/krb5.conf /etc/krb5.conf~
# /usr/local/sbin/telnetd -debug 3121 [now telnet to port 3121]
Segmentation Fault - core dumped




Responsible-Changed-From-To: krb5-unassigned->tlyu
Responsible-Changed-By: tlyu
Responsible-Changed-When: Sun Apr 5 19:54:19 1998
Responsible-Changed-Why:

Mine now.

State-Changed-From-To: open-feedback
State-Changed-By: tlyu
State-Changed-When: Sun Apr 5 19:54:31 1998
State-Changed-Why:

Should be fixed now.
src/lib/krb4/g_cnffile.c 1.5


From: Tom Yu <tlyu@MIT.EDU>
To: marty@caltrans.ca.gov
Cc: krb5-bugs@MIT.EDU, marty@db1.caltrans.ca.gov
Subject: Re: krb5-appl/555: telnetd segv's if /etc/krb5.conf doesn't exist
Date: Sun, 5 Apr 1998 19:56:28 -0400 (EDT)

Thanks for the bug report. Please let me know if the following patch
fixes the problem.

---Tom

Index: ChangeLog
===================================================================
RCS file: /cvs/krbdev/krb5/src/lib/krb4/ChangeLog,v
retrieving revision 1.62
diff -u -r1.62 ChangeLog
--- ChangeLog 1998/02/18 23:17:05 1.62
+++ ChangeLog 1998/04/05 23:55:21
@@ -1,3 +1,8 @@
+Sun Apr 5 19:51:21 1998 Tom Yu <tlyu@mit.edu>
+
+ * g_cnffile.c (krb__get_srvtabname): Fix up to not free context
+ unless it is valid.
+
Wed Feb 18 16:17:49 1998 Tom Yu <tlyu@mit.edu>

* Makefile.in: Remove trailing slash from thisconfigdir. Fix up
Index: g_cnffile.c
===================================================================
RCS file: /cvs/krbdev/krb5/src/lib/krb4/g_cnffile.c,v
retrieving revision 1.4
diff -u -r1.4 g_cnffile.c
--- g_cnffile.c 1997/08/07 20:32:14 1.4
+++ g_cnffile.c 1998/04/05 23:55:21
@@ -70,7 +70,8 @@
}else {
retname = strdup(default_srvtabname);
}
- krb5_free_context(context);
+ if (context != NULL)
+ krb5_free_context(context);
return retname;
}