Ticket History #317: krb__get_srvtabname() segfaults if krb5.conf missing

From schemers@slapshot.stanford.edu Sun Dec 22 18:51:43 1996
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 SAA24561 for <bugs@RT-11.MIT.EDU>; Sun, 22 Dec 1996 18:51:43 -0500
Received: from slapshot.Stanford.EDU by MIT.EDU with SMTP
id AA19493; Sun, 22 Dec 96 18:51:37 EST
Received: (from schemers@localhost) by slapshot.stanford.edu (8.8.4/8.7.3) id PAA20539; Sun, 22 Dec 1996 15:50:41 -0800 (PST)
Message-Id: <wnik9qagmup.fsf@slapshot.stanford.edu>
Date: 22 Dec 1996 15:50:38 -0800
From: Roland Schemers <schemers@stanford.edu>
Sender: schemers@slapshot.stanford.edu
Cc: krb5-bugs@MIT.EDU
In-Reply-To: blizzard@odin.nyser.net's message of 22 Dec 1996 21:35:55 GMT
Subject: krb__get_srvtabname() segfaults if krb5.conf missing
References: <59k9jr$4ka@news.appliedtheory.com>

The following message is a courtesy copy of an article
that has been posted as well.

blizzard@odin.nyser.net (Christopher Blizzard) writes:

The bug is in src/lib/krb4/g_cnffile.c:krb__get_srvtabname, line 61:

char *
krb__get_srvtabname(default_srvtabname)
char *default_srvtabname;
{
krb5_context context;
const char* names[3];
char **full_name = 0, **cpp;
krb5_error_code retval;
char *retname;

krb5_init_context(&context);
names[0] = "libdefaults";
names[1] = "krb4_srvtab";
names[2] = 0;
61: retval = profile_get_values(context->profile, names, &full_name);
if (retval == 0 && full_name && full_name[0]) {
retname = strdup(full_name[0]);
for (cpp = full_name; *cpp; cpp++)
krb5_xfree(*cpp);
krb5_xfree(full_name);
} else {
retname = strdup(default_srvtabname);
}
krb5_free_context(context);
return retname;
}

krb5_int_context is failing and setting context to NULL. Thus the call
to profile_get_values fails. Just need to rearrange things slightly, i.e:

krb5_init_context(&context);
names[0] = "libdefaults";
names[1] = "krb4_srvtab";
names[2] = 0;

if (context &&
(retval = profile_get_values(context->profile, names, &full_name))
&& retval == 0 && full_name && full_name[0]) {
retname = strdup(full_name[0]);
for (cpp = full_name; *cpp; cpp++)
krb5_xfree(*cpp);
krb5_xfree(full_name);
} else {
retname = strdup(default_srvtabname);
}
if (context) krb5_free_context(context);
return retname;

roland

Responsible-Changed-From-To: gnats-admin->tlyu
Responsible-Changed-By: tlyu
Responsible-Changed-When: Thu Mar 20 12:38:07 1997
Responsible-Changed-Why:

Refiled

State-Changed-From-To: open-analyzed
State-Changed-By: tlyu
State-Changed-When: Thu Mar 20 12:41:02 1997
State-Changed-Why:

This shouldn't be too hard to deal with.


From: Tom Yu <tlyu@MIT.EDU>
To: schemers@stanford.edu
Cc: krb5-bugs@MIT.EDU
Subject: Re: krb5-libs/317: krb__get_srvtabname() segfaults if krb5.conf missing
Date: Thu, 20 Mar 1997 12:43:01 -0500

We apologize for not getting back to you sooner, but we have in fact
received your bug report.

We have not had a chance yet to look at it in detail, but the changes
you suggest seem resonable.

---Tom

State-Changed-From-To: analyzed-closed
State-Changed-By: tlyu
State-Changed-When: Thu Aug 7 16:32:24 1997
State-Changed-Why:

Fixed
lib/krb4/g_cnffile.c 1.4