From 91e8872841e18eb96f2680fba180d636bb0a2a67 Mon Sep 17 00:00:00 2001
From: Noriko Hosoi <nhosoi@redhat.com>
Date: Fri, 18 Sep 2015 15:19:51 -0700
Subject: [PATCH 61/61] Ticket #48188 - segfault in ns-slapd due to accessing
Slapi_DN freed in pre bind plug-in
Description: Additional fixes based upon the comments by rmeggins@redhat.com
(Thank you, Rich!!).
https://fedorahosted.org/389/ticket/48188?replyto=24#comment:24
1. Implemented the case 2)
If the plugin changes the SLAPI_BIND_TARGET_SDN *value*,
we need to select a different backend. It is possible
(but not very useful) for the plugin to change the pointer,
but use the same value.
2. Added an api slapi_be_select_exact which returns NULL if
there is no matching backend.
https://fedorahosted.org/389/ticket/48188
Reviewed by rmeggins@redhat.com (Thank you!)
(cherry picked from commit 8212a8913b748cd1f5e986a754c37ef41db8272a)
(cherry picked from commit a215c006e0900caaa555def9e047e295844d8652)
---
ldap/servers/slapd/bind.c | 47 +++++++++++++++++++++++++++++----------
ldap/servers/slapd/mapping_tree.c | 19 ++++++++++++++++
ldap/servers/slapd/slapi-plugin.h | 1 +
3 files changed, 55 insertions(+), 12 deletions(-)
diff --git a/ldap/servers/slapd/bind.c b/ldap/servers/slapd/bind.c
index 4ec276a..474b508 100644
--- a/ldap/servers/slapd/bind.c
+++ b/ldap/servers/slapd/bind.c
@@ -107,6 +107,7 @@ do_bind( Slapi_PBlock *pb )
int auto_bind = 0;
int minssf = 0;
int minssf_exclude_rootdse = 0;
+ Slapi_DN *original_sdn = NULL;
LDAPDebug( LDAP_DEBUG_TRACE, "do_bind\n", 0, 0, 0 );
@@ -660,10 +661,9 @@ do_bind( Slapi_PBlock *pb )
goto free_and_return;
}
- if (referral)
- {
- send_referrals_from_entry(pb,referral);
- slapi_entry_free(referral);
+ if (referral) {
+ send_referrals_from_entry(pb,referral);
+ slapi_entry_free(referral);
goto free_and_return;
}
@@ -671,29 +671,50 @@ do_bind( Slapi_PBlock *pb )
/* not root dn - pass to the backend */
if ( be->be_bind != NULL ) {
-
+ original_sdn = slapi_sdn_dup(sdn);
/*
* call the pre-bind plugins. if they succeed, call
* the backend bind function. then call the post-bind
* plugins.
*/
if ( plugin_call_plugins( pb, SLAPI_PLUGIN_PRE_BIND_FN ) == 0 ) {
+ int sdn_updated = 0;
rc = 0;
/* Check if a pre_bind plugin mapped the DN to another backend */
Slapi_DN *pb_sdn;
slapi_pblock_get(pb, SLAPI_BIND_TARGET_SDN, &pb_sdn);
- if (pb_sdn != sdn) {
+ if (!pb_sdn) {
+ PR_snprintf(errorbuf, sizeof(errorbuf), "Pre-bind plug-in set NULL dn\n");
+ send_ldap_result(pb, LDAP_OPERATIONS_ERROR, NULL, errorbuf, 0, NULL);
+ goto free_and_return;
+ } else if ((pb_sdn != sdn) || (sdn_updated = slapi_sdn_compare(original_sdn, pb_sdn))) {
/*
* Slapi_DN set in pblock was changed by a pre bind plug-in.
* It is a plug-in's responsibility to free the original Slapi_DN.
*/
sdn = pb_sdn;
dn = slapi_sdn_get_dn(sdn);
-
- slapi_be_Unlock(be);
- be = slapi_be_select(sdn);
- slapi_be_Rlock(be);
+ if (!dn) {
+ PR_snprintf(errorbuf, sizeof(errorbuf), "Pre-bind plug-in set corrupted dn\n");
+ send_ldap_result(pb, LDAP_OPERATIONS_ERROR, NULL, errorbuf, 0, NULL);
+ goto free_and_return;
+ }
+ if (!sdn_updated) { /* pb_sdn != sdn; need to compare the dn's. */
+ sdn_updated = slapi_sdn_compare(original_sdn, sdn);
+ }
+ if (sdn_updated) { /* call slapi_be_select only when the DN is updated. */
+ slapi_be_Unlock(be);
+ be = slapi_be_select_exact(sdn);
+ if (be) {
+ slapi_be_Rlock(be);
+ slapi_pblock_set( pb, SLAPI_BACKEND, be );
+ } else {
+ PR_snprintf(errorbuf, sizeof(errorbuf), "No matching backend for %s\n", dn);
+ send_ldap_result(pb, LDAP_OPERATIONS_ERROR, NULL, errorbuf, 0, NULL);
+ goto free_and_return;
+ }
+ }
}
/*
@@ -845,10 +866,12 @@ account_locked:
}
free_and_return:;
- if (be)
+ slapi_sdn_free(&original_sdn);
+ if (be) {
slapi_be_Unlock(be);
+ }
if (bind_sdn_in_pb) {
- slapi_pblock_get(pb, SLAPI_BIND_TARGET_SDN, &sdn);
+ slapi_pblock_get(pb, SLAPI_BIND_TARGET_SDN, &sdn);
}
slapi_sdn_free(&sdn);
slapi_ch_free_string( &saslmech );
diff --git a/ldap/servers/slapd/mapping_tree.c b/ldap/servers/slapd/mapping_tree.c
index 165eba1..20c2cc3 100644
--- a/ldap/servers/slapd/mapping_tree.c
+++ b/ldap/servers/slapd/mapping_tree.c
@@ -3095,6 +3095,25 @@ slapi_be_select( const Slapi_DN *sdn ) /* JCM - The name of this should change??
return be;
}
+Slapi_Backend *
+slapi_be_select_exact(const Slapi_DN *sdn)
+{
+ Slapi_Backend *be = NULL;
+ mapping_tree_node *node = NULL;
+
+ if (!sdn) {
+ LDAPDebug0Args(LDAP_DEBUG_ANY, "slapi_be_select_exact: Empty Slapi_DN is given.\n");
+ return NULL;
+ }
+ node = slapi_get_mapping_tree_node_by_dn(sdn);
+
+ if (node && node->mtn_be) {
+ be = node->mtn_be[0];
+ }
+
+ return be;
+}
+
/* Check if the dn targets an internal reserved backends */
int
slapi_on_internal_backends(const Slapi_DN *sdn)
diff --git a/ldap/servers/slapd/slapi-plugin.h b/ldap/servers/slapd/slapi-plugin.h
index 6b04610..564da44 100644
--- a/ldap/servers/slapd/slapi-plugin.h
+++ b/ldap/servers/slapd/slapi-plugin.h
@@ -6338,6 +6338,7 @@ Slapi_Backend *slapi_be_new( const char *type, const char *name,
int isprivate, int logchanges );
void slapi_be_free(Slapi_Backend **be);
Slapi_Backend *slapi_be_select( const Slapi_DN *sdn );
+Slapi_Backend *slapi_be_select_exact(const Slapi_DN *sdn);
Slapi_Backend *slapi_be_select_by_instance_name( const char *name );
int slapi_be_exist(const Slapi_DN *sdn);
void slapi_be_delete_onexit(Slapi_Backend *be);
--
1.9.3