Ticket History #2759: fake-getaddrinfo.h incorrectly checks for gethostbyname_r errors

From krb5-bugs-incoming-bounces@mit.edu Tue Nov 2 13:29:01 2004
Received: from pch.mit.edu (PCH.MIT.EDU [18.7.21.90]) by krbdev.mit.edu (8.9.3p2) with ESMTP
id NAA01452; Tue, 2 Nov 2004 13:29:01 -0500 (EST)
Received: from pch.mit.edu (localhost [127.0.0.1])
by pch.mit.edu (8.12.8p2/8.12.8) with ESMTP id iA2IT1Xn026901
for <krb5-send-pr@krbdev.mit.edu>; Tue, 2 Nov 2004 13:29:01 -0500 (EST)
Received: from fort-point-station.mit.edu (FORT-POINT-STATION.MIT.EDU
[18.7.7.76])
by pch.mit.edu (8.12.8p2/8.12.8) with ESMTP id iA20QoXn001189
for <krb5-bugs-incoming@PCH.mit.edu>;
Mon, 1 Nov 2004 19:26:50 -0500 (EST)
Received: from mx1.redhat.com (mx1.redhat.com [66.187.233.31])
iA20QnfS011246
for <krb5-bugs@mit.edu>; Mon, 1 Nov 2004 19:26:49 -0500 (EST)
Received: from int-mx1.corp.redhat.com (int-mx1.corp.redhat.com
[172.16.52.254])
by mx1.redhat.com (8.12.11/8.12.11) with ESMTP id iA20Qm2W022293
for <krb5-bugs@mit.edu>; Mon, 1 Nov 2004 19:26:48 -0500
Received: from devserv.devel.redhat.com (devserv.devel.redhat.com
[172.16.58.1])
by int-mx1.corp.redhat.com (8.11.6/8.11.6) with ESMTP id iA20Qhr03050
for <krb5-bugs@mit.edu>; Mon, 1 Nov 2004 19:26:43 -0500
Received: from axe.boston.redhat.com (axe.boston.redhat.com [172.16.80.51])
iA20QeT5000611
for <krb5-bugs@mit.edu>; Mon, 1 Nov 2004 19:26:40 -0500
Received: from axe.boston.redhat.com (localhost.localdomain [127.0.0.1])
by axe.boston.redhat.com (8.13.1/8.13.1) with ESMTP id iA20F3Yp015843
for <krb5-bugs@mit.edu>; Mon, 1 Nov 2004 19:15:03 -0500
Received: (from nalin@localhost)
by axe.boston.redhat.com (8.13.1/8.13.1/Submit) id iA20F3xD015842;
Mon, 1 Nov 2004 19:15:03 -0500
Date: Mon, 1 Nov 2004 19:15:03 -0500
Message-Id: <200411020015.iA20F3xD015842@axe.boston.redhat.com>
To: krb5-bugs@mit.edu
From: nalin@redhat.com
X-send-pr-version: 3.99
X-Scanned-By: MIMEDefang 2.42
X-Mailman-Approved-At: Tue, 02 Nov 2004 13:29:00 -0500
Subject: error checking result of gethostbyname_r
X-BeenThere: krb5-bugs-incoming@mit.edu
X-Mailman-Version: 2.1
Precedence: list
Reply-To: nalin@redhat.com
Sender: krb5-bugs-incoming-bounces@mit.edu
Errors-To: krb5-bugs-incoming-bounces@mit.edu


System: Linux axe.boston.redhat.com 2.6.8-1.624smp #1 SMP Thu Oct 14 21:16:29 EDT 2004 i686 i686 i386 GNU/Linux
Architecture: i686

When GETHOSTBYNAME_R_RETURNS_INT is set by configure, the current
implementation of GET_HOST_BY_NAME checks for errors from
gethostbyname_r by checking its result code. An error has also
occurred if my_hp has not been set to point to my_h_ent.
On my setup, configuring a host with only an IPv6 address in
/etc/hosts was enough to trigger the bug.
In addition to checking if the numeric result returned by
gethostbyname_r is non-zero, check that my_hp has been set to
point to my_h_ent. Suggested patch:

--- src/include/fake-addrinfo.h 2004-09-02 18:59:42.000000000 -0400
+++ src/include/fake-addrinfo.h 2004-11-01 19:17:30.127252336 -0500
@@ -187,24 +187,27 @@ extern /*@dependent@*/ char *gai_strerro
#ifdef GETHOSTBYNAME_R_RETURNS_INT
#define GET_HOST_BY_NAME(NAME, HP, ERR) \
{ \
- struct hostent my_h_ent, *my_hp; \
- int my_h_err; \
+ struct hostent my_h_ent, *my_hp = NULL; \
+ int my_h_err, my_ret; \
char my_h_buf[8192]; \
- (HP) = (gethostbyname_r((NAME), &my_h_ent, \
- my_h_buf, sizeof (my_h_buf), &my_hp, \
- &my_h_err) \
+ my_ret = (gethostbyname_r((NAME), &my_h_ent, \
+ my_h_buf, sizeof (my_h_buf), &my_hp, \
+ &my_h_err)); \
+ (HP) = (((my_ret != 0) || (my_hp != &my_h_ent)) \
? 0 \
: &my_h_ent); \
(ERR) = my_h_err; \
}
#define GET_HOST_BY_ADDR(ADDR, ADDRLEN, FAMILY, HP, ERR) \
{ \
- struct hostent my_h_ent, *my_hp; \
- int my_h_err; \
+ struct hostent my_h_ent, *my_hp = NULL; \
+ int my_h_err, my_ret; \
char my_h_buf[8192]; \
- (HP) = (gethostbyaddr_r((ADDR), (ADDRLEN), (FAMILY), &my_h_ent, \
- my_h_buf, sizeof (my_h_buf), &my_hp, \
- &my_h_err) \
+ my_ret = (gethostbyaddr_r((ADDR), (ADDRLEN), (FAMILY), \
+ &my_h_ent, \
+ my_h_buf, sizeof (my_h_buf), &my_hp, \
+ &my_h_err)); \
+ (HP) = (((my_ret != 0) || (my_hp != &my_h_ent)) \
? 0 \
: &my_h_ent); \
(ERR) = my_h_err; \

(GET_HOST_BY_NAME, GET_HOST_BY_ADDR) [GETHOSTBYNAME_RETURNS_INT]: Test
the output hostent pointer as an additional way of checking for errors.
Original patch from Nalin Dahyabhai, needed some tweaking to fit in
current sources, especially as updated in ticket 3911.

Commit By: raeburn



Revision: 18183
Changed Files:
U trunk/src/util/support/fake-addrinfo.c

*sigh*
Stupid typo in last change.

Commit By: raeburn



Revision: 18184
Changed Files:
U trunk/src/util/support/fake-addrinfo.c