From cb9ed81e6b1fdd26a06739fe819b730eb4a70839 Mon Sep 17 00:00:00 2001
From: Petr Spacek <pspacek@redhat.com>
Date: Apr 09 2014 14:31:53 +0000
Subject: Prevent NULL dereference before sync_concurr_limit_signal() calls.


Missing check was causing NULL dereference in case where
manager_get_ldap_instance() failed. This typically happens when BIND
is processing LDAP updates during shutdown.

Signed-off-by: Petr Spacek <pspacek@redhat.com>

---

diff --git a/NEWS b/NEWS
index e787e7f..78843f2 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,8 @@
+4.3
+====
+[1] LDAP update processing was fixed to prevent BIND from crashing during
+    shutdown.
+
 4.2
 ====
 [1] Record parsing was fixed to prevent child-zone data corruption in cases
diff --git a/src/ldap_helper.c b/src/ldap_helper.c
index 678e9f8..cf8d45e 100644
--- a/src/ldap_helper.c
+++ b/src/ldap_helper.c
@@ -3913,16 +3913,18 @@ update_zone(isc_task_t *task, isc_event_t *event)
 	}
 
 cleanup:
-	sync_concurr_limit_signal(inst->sctx);
+	if (inst != NULL) {
+		sync_concurr_limit_signal(inst->sctx);
+		if (dns_name_dynamic(&currname))
+			dns_name_free(&currname, inst->mctx);
+		if (dns_name_dynamic(&prevname))
+			dns_name_free(&prevname, inst->mctx);
+	}
 	if (result != ISC_R_SUCCESS)
 		log_error_r("update_zone (syncrepl) failed for '%s'. "
 			  "Zones can be outdated, run `rndc reload`",
 			  pevent->dn);
 
-	if (dns_name_dynamic(&currname))
-		dns_name_free(&currname, inst->mctx);
-	if (dns_name_dynamic(&prevname))
-		dns_name_free(&prevname, inst->mctx);
 	isc_mem_free(mctx, pevent->dbname);
 	if (pevent->prevdn != NULL)
 		isc_mem_free(mctx, pevent->prevdn);
@@ -3948,7 +3950,8 @@ update_config(isc_task_t *task, isc_event_t *event)
 	CHECK(ldap_parse_configentry(entry, inst));
 
 cleanup:
-	sync_concurr_limit_signal(inst->sctx);
+	if (inst != NULL)
+		sync_concurr_limit_signal(inst->sctx);
 	if (result != ISC_R_SUCCESS)
 		log_error_r("update_config (syncrepl) failed for '%s'. "
 			    "Configuration can be outdated, run `rndc reload`",
@@ -4200,17 +4203,19 @@ cleanup:
 			  pevent->dn, pevent->chgtype);
 	}
 
-	sync_concurr_limit_signal(inst->sctx);
+	if (inst != NULL) {
+		sync_concurr_limit_signal(inst->sctx);
+		if (dns_name_dynamic(&name))
+			dns_name_free(&name, inst->mctx);
+		if (dns_name_dynamic(&prevname))
+			dns_name_free(&prevname, inst->mctx);
+		if (dns_name_dynamic(&origin))
+			dns_name_free(&origin, inst->mctx);
+		if (dns_name_dynamic(&prevorigin))
+			dns_name_free(&prevorigin, inst->mctx);
+	}
 	if (zone_ptr != NULL)
 		dns_zone_detach(&zone_ptr);
-	if (dns_name_dynamic(&name))
-		dns_name_free(&name, inst->mctx);
-	if (dns_name_dynamic(&prevname))
-		dns_name_free(&prevname, inst->mctx);
-	if (dns_name_dynamic(&origin))
-		dns_name_free(&origin, inst->mctx);
-	if (dns_name_dynamic(&prevorigin))
-		dns_name_free(&prevorigin, inst->mctx);
 	ldapdb_rdatalist_destroy(mctx, &rdatalist);
 	isc_mem_free(mctx, pevent->dbname);
 	if (pevent->prevdn != NULL)