[krb5] - apply upstream patch to fix a null pointer dereference with the LDAP kdb backend (CVE-2011-1527, #

[Nalin Dahyabhai]

commit af8b5467900692da3f749d90b05837076df5bed7
Author: Nalin Dahyabhai <nalin at dahyabhai.net>
Date:   Tue Oct 18 14:28:08 2011 -0400

    - apply upstream patch to fix a null pointer dereference with the LDAP kdb backend (CVE-2011-1527, #744125), an assertion failure with multiple kdb backends (CVE-2011-1528), and a null pointer dereference with multiple kdb backends (CVE-2011-1529) (#737711)

 krb5-1.9-MITKRB5-SA-2011-006.patch |   75 ++++++++++++++++++++++++++++++++++++
 krb5.spec                          |   10 ++++-
 2 files changed, 84 insertions(+), 1 deletions(-)
---
diff --git a/krb5-1.9-MITKRB5-SA-2011-006.patch b/krb5-1.9-MITKRB5-SA-2011-006.patch
new file mode 100644
index 0000000..05a22ca
--- /dev/null
+++ b/krb5-1.9-MITKRB5-SA-2011-006.patch
@@ -0,0 +1,75 @@
+diff --git a/src/plugins/kdb/db2/lockout.c b/src/plugins/kdb/db2/lockout.c
+index b473611..50c60b7 100644
+--- a/src/plugins/kdb/db2/lockout.c
++++ b/src/plugins/kdb/db2/lockout.c
+@@ -169,6 +169,9 @@ krb5_db2_lockout_audit(krb5_context context,
+         return 0;
+     }
+ 
++    if (entry == NULL)
++        return 0;
++
+     if (!db_ctx->disable_lockout) {
+         code = lookup_lockout_policy(context, entry, &max_fail,
+                                      &failcnt_interval, &lockout_duration);
+@@ -176,6 +179,15 @@ krb5_db2_lockout_audit(krb5_context context,
+             return code;
+     }
+ 
++    /*
++     * Don't continue to modify the DB for an already locked account.
++     * (In most cases, status will be KRB5KDC_ERR_CLIENT_REVOKED, and
++     * this check is unneeded, but in rare cases, we can fail with an
++     * integrity error or preauth failure before a policy check.)
++     */
++    if (locked_check_p(context, stamp, max_fail, lockout_duration, entry))
++        return 0;
++
+     /* Only mark the authentication as successful if the entry
+      * required preauthentication, otherwise we have no idea. */
+     if (status == 0 && (entry->attributes & KRB5_KDB_REQUIRES_PRE_AUTH)) {
+diff --git a/src/plugins/kdb/ldap/libkdb_ldap/ldap_principal2.c b/src/plugins/kdb/ldap/libkdb_ldap/ldap_principal2.c
+index 552e39a..c2f44ab 100644
+--- a/src/plugins/kdb/ldap/libkdb_ldap/ldap_principal2.c
++++ b/src/plugins/kdb/ldap/libkdb_ldap/ldap_principal2.c
+@@ -105,6 +105,7 @@ krb5_ldap_get_principal(krb5_context context, krb5_const_principal searchfor,
+     CHECK_LDAP_HANDLE(ldap_context);
+ 
+     if (is_principal_in_realm(ldap_context, searchfor) != 0) {
++        st = KRB5_KDB_NOENTRY;
+         krb5_set_error_message (context, st, "Principal does not belong to realm");
+         goto cleanup;
+     }
+diff --git a/src/plugins/kdb/ldap/libkdb_ldap/lockout.c b/src/plugins/kdb/ldap/libkdb_ldap/lockout.c
+index a218dc7..fd164dd 100644
+--- a/src/plugins/kdb/ldap/libkdb_ldap/lockout.c
++++ b/src/plugins/kdb/ldap/libkdb_ldap/lockout.c
+@@ -165,6 +165,9 @@ krb5_ldap_lockout_audit(krb5_context context,
+         return 0;
+     }
+ 
++    if (entry == NULL)
++        return 0;
++
+     if (!ldap_context->disable_lockout) {
+         code = lookup_lockout_policy(context, entry, &max_fail,
+                                      &failcnt_interval,
+@@ -173,9 +176,16 @@ krb5_ldap_lockout_audit(krb5_context context,
+             return code;
+     }
+ 
+-    entry->mask = 0;
++    /*
++     * Don't continue to modify the DB for an already locked account.
++     * (In most cases, status will be KRB5KDC_ERR_CLIENT_REVOKED, and
++     * this check is unneeded, but in rare cases, we can fail with an
++     * integrity error or preauth failure before a policy check.)
++     */
++    if (locked_check_p(context, stamp, max_fail, lockout_duration, entry))
++        return 0;
+ 
+-    assert (!locked_check_p(context, stamp, max_fail, lockout_duration, entry));
++    entry->mask = 0;
+ 
+     /* Only mark the authentication as successful if the entry
+      * required preauthentication, otherwise we have no idea. */
diff --git a/krb5.spec b/krb5.spec
index ed2a2fd..ca04309 100644
--- a/krb5.spec
+++ b/krb5.spec
@@ -6,7 +6,7 @@
 Summary: The Kerberos network authentication system
 Name: krb5
 Version: 1.9.1
-Release: 17%{?dist}
+Release: 18%{?dist}
 # Maybe we should explode from the now-available-to-everybody tarball instead?
 # http://web.mit.edu/kerberos/dist/krb5/1.9/krb5-1.9.1-signed.tar
 Source0: krb5-%{version}.tar.gz
@@ -64,6 +64,7 @@ Patch87: krb5-1.9.1-sendto_poll2.patch
 Patch88: krb5-1.9-crossrealm.patch
 Patch89: krb5-1.9.1-sendto_poll3.patch
 Patch90: krb5-trunk-ext_pac_sign.patch
+Patch91: krb5-1.9-MITKRB5-SA-2011-006.patch
 
 License: MIT
 URL: http://web.mit.edu/kerberos/www/
@@ -225,6 +226,7 @@ ln -s NOTICE LICENSE
 %patch88 -p1 -b .crossrealm
 %patch89 -p1 -b .sendto_poll3
 %patch90 -p1 -b .ext_pac_sign
+%patch91 -p1 -b .2011-006
 gzip doc/*.ps
 
 sed -i -e '1s!\[twoside\]!!;s!%\(\\usepackage{hyperref}\)!\1!' doc/api/library.tex
@@ -703,6 +705,12 @@ exit 0
 %{_sbindir}/uuserver
 
 %changelog
+* Tue Oct 18 2011 Nalin Dahyabhai <nalin at redhat.com> 1.9.1-18
+- apply upstream patch to fix a null pointer dereference with the LDAP kdb
+  backend (CVE-2011-1527, #744125), an assertion failure with multiple kdb
+  backends (CVE-2011-1528), and a null pointer dereference with multiple kdb
+  backends (CVE-2011-1529) (#737711)
+
 * Thu Oct 13 2011 Nalin Dahyabhai <nalin at redhat.com> 1.9.1-17
 - pull in patch from trunk to rename krb5int_pac_sign() to krb5_pac_sign() and
   make it public (#745533)