json: Modify API to use return codes

Modify the auditing JSON API to return a response code, as the consensus
was that the existing error handling was aesthetically displeasing.

Signed-off-by: Gary Lockyer <gary@catalyst.net.nz>
Reviewed-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>

cherry picked from commit 79f494e51eabb5176747fcf3b9f2efad10ec7f97 and
adapted to compile on 4.9 by Gary Lockyer)

8 files changed, 1350 insertions, 474 deletions

diff --git a/auth/auth_log.c b/auth/auth_log.c
index 38d29db4396..3e81730ef14 100644
--- a/auth/auth_log.c
+++ b/auth/auth_log.c
@@ -123,63 +123,134 @@ static void log_authentication_event_json(
 	struct dom_sid *sid,
 	int debug_level)
 {
-	struct json_object wrapper = json_new_object();
-	struct json_object authentication;
+	struct json_object wrapper = json_empty_object;
+	struct json_object authentication = json_empty_object;
 	char negotiate_flags[11];
-
-	json_add_timestamp(&wrapper);
-	json_add_string(&wrapper, "type", AUTH_JSON_TYPE);
+	int rc = 0;
 
 	authentication = json_new_object();
-	json_add_version(&authentication, AUTH_MAJOR, AUTH_MINOR);
-	json_add_string(&authentication, "status", nt_errstr(status));
-	json_add_address(&authentication, "localAddress", ui->local_host);
-	json_add_address(&authentication, "remoteAddress", ui->remote_host);
-	json_add_string(&authentication,
-			"serviceDescription",
-			ui->service_description);
-	json_add_string(&authentication,
-			"authDescription",
-			ui->auth_description);
-	json_add_string(&authentication,
-			"clientDomain",
-			ui->client.domain_name);
-	json_add_string(&authentication,
-			"clientAccount",
-			ui->client.account_name);
-	json_add_string(&authentication,
-			"workstation",
-			ui->workstation_name);
-	json_add_string(&authentication, "becameAccount", account_name);
-	json_add_string(&authentication, "becameDomain", domain_name);
-	json_add_sid(&authentication, "becameSid", sid);
-	json_add_string(&authentication,
-			"mappedAccount",
-			ui->mapped.account_name);
-	json_add_string(&authentication,
-			"mappedDomain",
-			ui->mapped.domain_name);
-	json_add_string(&authentication,
-			"netlogonComputer",
-			ui->netlogon_trust_account.computer_name);
-	json_add_string(&authentication,
-			"netlogonTrustAccount",
-			ui->netlogon_trust_account.account_name);
+	if (json_is_invalid(&authentication)) {
+		goto failure;
+	}
+	rc = json_add_version(&authentication, AUTH_MAJOR, AUTH_MINOR);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&authentication, "status", nt_errstr(status));
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_address(&authentication, "localAddress", ui->local_host);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc =
+	    json_add_address(&authentication, "remoteAddress", ui->remote_host);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authentication, "serviceDescription", ui->service_description);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authentication, "authDescription", ui->auth_description);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authentication, "clientDomain", ui->client.domain_name);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authentication, "clientAccount", ui->client.account_name);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authentication, "workstation", ui->workstation_name);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&authentication, "becameAccount", account_name);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&authentication, "becameDomain", domain_name);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_sid(&authentication, "becameSid", sid);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authentication, "mappedAccount", ui->mapped.account_name);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authentication, "mappedDomain", ui->mapped.domain_name);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&authentication,
+			     "netlogonComputer",
+			     ui->netlogon_trust_account.computer_name);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&authentication,
+			     "netlogonTrustAccount",
+			     ui->netlogon_trust_account.account_name);
+	if (rc != 0) {
+		goto failure;
+	}
 	snprintf(negotiate_flags,
 		 sizeof( negotiate_flags),
 		 "0x%08X",
 		 ui->netlogon_trust_account.negotiate_flags);
-	json_add_string(&authentication,
-			"netlogonNegotiateFlags",
-			negotiate_flags);
-	json_add_int(&authentication,
-		     "netlogonSecureChannelType",
-		     ui->netlogon_trust_account.secure_channel_type);
-	json_add_sid(&authentication,
-		     "netlogonTrustAccountSid",
-		     ui->netlogon_trust_account.sid);
-	json_add_string(&authentication, "passwordType", get_password_type(ui));
-	json_add_object(&wrapper, AUTH_JSON_TYPE, &authentication);
+	rc = json_add_string(
+	    &authentication, "netlogonNegotiateFlags", negotiate_flags);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_int(&authentication,
+			  "netlogonSecureChannelType",
+			  ui->netlogon_trust_account.secure_channel_type);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_sid(&authentication,
+			  "netlogonTrustAccountSid",
+			  ui->netlogon_trust_account.sid);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authentication, "passwordType", get_password_type(ui));
+	if (rc != 0) {
+		goto failure;
+	}
+
+	wrapper = json_new_object();
+	if (json_is_invalid(&wrapper)) {
+		goto failure;
+	}
+	rc = json_add_timestamp(&wrapper);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&wrapper, "type", AUTH_JSON_TYPE);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_object(&wrapper, AUTH_JSON_TYPE, &authentication);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	/*
 	 * While not a general-purpose profiling solution this will
@@ -192,9 +263,10 @@ static void log_authentication_event_json(
 		struct timeval current_time = timeval_current();
 		uint64_t duration =  usec_time_diff(&current_time,
 						    start_time);
-		json_add_int(&authentication,
-			     "duration",
-			     duration);
+		rc = json_add_int(&authentication, "duration", duration);
+		if (rc != 0) {
+			goto failure;
+		}
 	}
 
 	log_json(msg_ctx,
@@ -204,6 +276,16 @@ static void log_authentication_event_json(
 		 DBGC_AUTH_AUDIT_JSON,
 		 debug_level);
 	json_free(&wrapper);
+	return;
+failure:
+	/*
+	 * On a failure authentication will not have been added to wrapper so it
+	 * needs to be freed to avoid a leak.
+	 *
+	 */
+	json_free(&authentication);
+	json_free(&wrapper);
+	DBG_ERR("Failed to write authentication event JSON log message\n");
 }
 
 /*
@@ -237,45 +319,92 @@ static void log_successful_authz_event_json(
 	struct auth_session_info *session_info,
 	int debug_level)
 {
-	struct json_object wrapper = json_new_object();
-	struct json_object authorization;
+	struct json_object wrapper = json_empty_object;
+	struct json_object authorization = json_empty_object;
 	char account_flags[11];
+	int rc = 0;
 
-	json_add_timestamp(&wrapper);
-	json_add_string(&wrapper, "type", AUTHZ_JSON_TYPE);
 	authorization = json_new_object();
-	json_add_version(&authorization, AUTHZ_MAJOR, AUTHZ_MINOR);
-	json_add_address(&authorization, "localAddress", local);
-	json_add_address(&authorization, "remoteAddress", remote);
-	json_add_string(&authorization,
-			"serviceDescription",
-			service_description);
-	json_add_string(&authorization, "authType", auth_type);
-	json_add_string(&authorization,
-			"domain",
-			session_info->info->domain_name);
-	json_add_string(&authorization,
-			"account",
-			session_info->info->account_name);
-	json_add_sid(&authorization,
-		     "sid",
-		     &session_info->security_token->sids[0]);
-	json_add_guid(&authorization,
-		      "sessionId",
-		      &session_info->unique_session_token);
-	json_add_string(&authorization,
-			"logonServer",
-			session_info->info->logon_server);
-	json_add_string(&authorization,
-			"transportProtection",
-			transport_protection);
+	if (json_is_invalid(&authorization)) {
+		goto failure;
+	}
+	rc = json_add_version(&authorization, AUTHZ_MAJOR, AUTHZ_MINOR);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_address(&authorization, "localAddress", local);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_address(&authorization, "remoteAddress", remote);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authorization, "serviceDescription", service_description);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&authorization, "authType", auth_type);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authorization, "domain", session_info->info->domain_name);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authorization, "account", session_info->info->account_name);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_sid(
+	    &authorization, "sid", &session_info->security_token->sids[0]);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_guid(
+	    &authorization, "sessionId", &session_info->unique_session_token);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authorization, "logonServer", session_info->info->logon_server);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(
+	    &authorization, "transportProtection", transport_protection);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	snprintf(account_flags,
 		 sizeof(account_flags),
 		 "0x%08X",
 		 session_info->info->acct_flags);
-	json_add_string(&authorization, "accountFlags", account_flags);
-	json_add_object(&wrapper, AUTHZ_JSON_TYPE, &authorization);
+	rc = json_add_string(&authorization, "accountFlags", account_flags);
+	if (rc != 0) {
+		goto failure;
+	}
+
+	wrapper = json_new_object();
+	if (json_is_invalid(&wrapper)) {
+		goto failure;
+	}
+	rc = json_add_timestamp(&wrapper);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&wrapper, "type", AUTHZ_JSON_TYPE);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_object(&wrapper, AUTHZ_JSON_TYPE, &authorization);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	log_json(msg_ctx,
 		 lp_ctx,
@@ -284,6 +413,16 @@ static void log_successful_authz_event_json(
 		 DBGC_AUTH_AUDIT_JSON,
 		 debug_level);
 	json_free(&wrapper);
+	return;
+failure:
+	/*
+	 * On a failure authorization will not have been added to wrapper so it
+	 * needs to be freed to avoid a leak.
+	 *
+	 */
+	json_free(&authorization);
+	json_free(&wrapper);
+	DBG_ERR("Unable to log Authentication event JSON audit message\n");
 }
 
 #else
diff --git a/lib/audit_logging/audit_logging.c b/lib/audit_logging/audit_logging.c
index f94f2c2a839..ac08863129a 100644
--- a/lib/audit_logging/audit_logging.c
+++ b/lib/audit_logging/audit_logging.c
@@ -20,31 +20,6 @@
 /*
  * Error handling:
  *
- * The json_object structure contains a boolean 'error'.  This is set whenever
- * an error is detected. All the library functions check this flag and return
- * immediately if it is set.
- *
- *	if (object->error) {
- *		return;
- *	}
- *
- * This allows the operations to be sequenced naturally with out the clutter
- * of error status checks.
- *
- *	audit = json_new_object();
- *	json_add_version(&audit, OPERATION_MAJOR, OPERATION_MINOR);
- *	json_add_int(&audit, "statusCode", ret);
- *	json_add_string(&audit, "status", ldb_strerror(ret));
- *	json_add_string(&audit, "operation", operation);
- *	json_add_address(&audit, "remoteAddress", remote);
- *	json_add_sid(&audit, "userSid", sid);
- *	json_add_string(&audit, "dn", dn);
- *	json_add_guid(&audit, "transactionId", &ac->transaction_guid);
- *	json_add_guid(&audit, "sessionId", unique_session_token);
- *
- * The assumptions are that errors will be rare, and that the audit logging
- * code should not cause failures. So errors are logged but processing
- * continues on a best effort basis.
  */
 
 #include "includes.h"
@@ -67,7 +42,7 @@
  *
  * @param mem_ctx talloc memory context that owns the returned string.
  *
- * @return a human readable time stamp.
+ * @return a human readable time stamp, or NULL in the event of an error.
  *
  */
 char* audit_get_timestamp(TALLOC_CTX *frame)
@@ -76,11 +51,11 @@ char* audit_get_timestamp(TALLOC_CTX *frame)
 	char tz[10];		/* formatted time zone			 */
 	struct tm* tm_info;	/* current local time			 */
 	struct timeval tv;	/* current system time			 */
-	int r;			/* response code from gettimeofday	 */
+	int ret;		/* response code			 */
 	char * ts;		/* formatted time stamp			 */
 
-	r = gettimeofday(&tv, NULL);
-	if (r) {
+	ret = gettimeofday(&tv, NULL);
+	if (ret != 0) {
 		DBG_ERR("Unable to get time of day: (%d) %s\n",
 			errno,
 			strerror(errno));
@@ -122,6 +97,10 @@ void audit_log_human_text(const char* prefix,
 
 #ifdef HAVE_JANSSON
 /*
+ * Constant for empty json object initialisation
+ */
+const struct json_object json_empty_object = {.valid = false, .root = NULL};
+/*
  * @brief write a json object to the samba audit logs.
  *
  * Write the json object to the audit logs as a formatted string
@@ -136,8 +115,23 @@ void audit_log_json(const char* prefix,
 		    int debug_class,
 		    int debug_level)
 {
-	TALLOC_CTX *ctx = talloc_new(NULL);
-	char *s = json_to_string(ctx, message);
+	TALLOC_CTX *ctx = NULL;
+	char *s = NULL;
+
+	if (json_is_invalid(message)) {
+		DBG_ERR("Invalid JSON object, unable to log\n");
+		return;
+	}
+
+	ctx = talloc_new(NULL);
+	s = json_to_string(ctx, message);
+	if (s == NULL) {
+		DBG_ERR("json_to_string for (%s) returned NULL, "
+			"JSON audit message could not written\n",
+			prefix);
+		TALLOC_FREE(ctx);
+		return;
+	}
 	DEBUGC(debug_class, debug_level, ("JSON %s: %s\n", prefix, s));
 	TALLOC_FREE(ctx);
 }
@@ -235,11 +229,14 @@ void audit_message_send(
 
 	const char *message_string = NULL;
 	DATA_BLOB message_blob = data_blob_null;
-	TALLOC_CTX *ctx = talloc_new(NULL);
+	TALLOC_CTX *ctx = NULL;
 
+	if (json_is_invalid(message)) {
+		DBG_ERR("Invalid JSON object, unable to send\n");
+		return;
+	}
 	if (msg_ctx == NULL) {
 		DBG_DEBUG("No messaging context\n");
-		TALLOC_FREE(ctx);
 		return;
 	}
 
@@ -288,20 +285,21 @@ void audit_message_send(
  * Free with a call to json_free_object, note that the jansson inplementation
  * allocates memory with malloc and not talloc.
  *
- * @return a struct json_object, error will be set to true if the object
+ * @return a struct json_object, valid will be set to false if the object
  *         could not be created.
  *
  */
 struct json_object json_new_object(void) {
 
-	struct json_object object;
-	object.error = false;
+	struct json_object object = json_empty_object;
 
 	object.root = json_object();
 	if (object.root == NULL) {
-		object.error = true;
-		DBG_ERR("Unable to create json_object\n");
+		object.valid = false;
+		DBG_ERR("Unable to create JSON object\n");
+		return object;
 	}
+	object.valid = true;
 	return object;
 }
 
@@ -320,14 +318,15 @@ struct json_object json_new_object(void) {
  */
 struct json_object json_new_array(void) {
 
-	struct json_object array;
-	array.error = false;
+	struct json_object array = json_empty_object;
 
 	array.root = json_array();
 	if (array.root == NULL) {
-		array.error = true;
-		DBG_ERR("Unable to create json_array\n");
+		array.valid = false;
+		DBG_ERR("Unable to create JSON array\n");
+		return array;
 	}
+	array.valid = true;
 	return array;
 }
 
@@ -345,7 +344,7 @@ void json_free(struct json_object *object)
 		json_decref(object->root);
 	}
 	object->root = NULL;
-	object->error = true;
+	object->valid = false;
 }
 
 /*
@@ -358,99 +357,131 @@ void json_free(struct json_object *object)
  */
 bool json_is_invalid(struct json_object *object)
 {
-	return object->error;
+	return !object->valid;
 }
 
 /*
  * @brief Add an integer value to a JSON object.
  *
  * Add an integer value named 'name' to the json object.
- * In the event of an error object will be invalidated.
  *
  * @param object the JSON object to be updated.
  * @param name the name of the value.
  * @param value the value.
  *
+ * @return 0 the operation was successful
+ *        -1 the operation failed
+ *
  */
-void json_add_int(struct json_object *object,
-		  const char* name,
-		  const int value)
+int json_add_int(struct json_object *object, const char *name, const int value)
 {
-	int rc = 0;
+	int ret = 0;
+	json_t *integer = NULL;
 
-	if (object->error) {
-		return;
+	if (json_is_invalid(object)) {
+		DBG_ERR("Unable to add int [%s] value [%d], "
+			"target object is invalid\n",
+			name,
+			value);
+		return JSON_ERROR;
+	}
+
+	integer = json_integer(value);
+	if (integer == NULL) {
+		DBG_ERR("Unable to create integer value [%s] value [%d]\n",
+			name,
+			value);
+		return JSON_ERROR;
 	}
 
-	rc = json_object_set_new(object->root, name, json_integer(value));
-	if (rc) {
-		DBG_ERR("Unable to set name [%s] value [%d]\n", name, value);
-		object->error = true;
+	ret = json_object_set_new(object->root, name, integer);
+	if (ret != 0) {
+		json_decref(integer);
+		DBG_ERR("Unable to add int [%s] value [%d]\n", name, value);
 	}
+	return ret;
 }
 
 /*
  * @brief Add a boolean value to a JSON object.
  *
  * Add a boolean value named 'name' to the json object.
- * In the event of an error object will be invalidated.
  *
  * @param object the JSON object to be updated.
  * @param name the name.
  * @param value the value.
  *
+ * @return 0 the operation was successful
+ *        -1 the operation failed
+ *
  */
-void json_add_bool(struct json_object *object,
-		   const char* name,
-		   const bool value)
+int json_add_bool(struct json_object *object,
+		  const char *name,
+		  const bool value)
 {
-	int rc = 0;
+	int ret = 0;
 
-	if (object->error) {
-		return;
+	if (json_is_invalid(object)) {
+		DBG_ERR("Unable to add boolean [%s] value [%d], "
+			"target object is invalid\n",
+			name,
+			value);
+		return JSON_ERROR;
 	}
 
-	rc = json_object_set_new(object->root, name, json_boolean(value));
-	if (rc) {
-		DBG_ERR("Unable to set name [%s] value [%d]\n", name, value);
-		object->error = true;
+	ret = json_object_set_new(object->root, name, json_boolean(value));
+	if (ret != 0) {
+		DBG_ERR("Unable to add boolean [%s] value [%d]\n", name, value);
 	}
-
+	return ret;
 }
 
 /*
  * @brief Add a string value to a JSON object.
  *
  * Add a string value named 'name' to the json object.
- * In the event of an error object will be invalidated.
  *
  * @param object the JSON object to be updated.
  * @param name the name.
  * @param value the value.
  *
+ * @return 0 the operation was successful
+ *        -1 the operation failed
+ *
  */
-void json_add_string(struct json_object *object,
-		     const char* name,
-		     const char* value)
+int json_add_string(struct json_object *object,
+		    const char *name,
+		    const char *value)
 {
-	int rc = 0;
+	int ret = 0;
 
-	if (object->error) {
-		return;
+	if (json_is_invalid(object)) {
+		DBG_ERR("Unable to add string [%s], target object is invalid\n",
+			name);
+		return JSON_ERROR;
 	}
-
 	if (value) {
-		rc = json_object_set_new(
-			object->root,
-			name,
-			json_string(value));
+		json_t *string = json_string(value);
+		if (string == NULL) {
+			DBG_ERR("Unable to add string [%s], "
+				"could not create string object\n",
+				name);
+			return JSON_ERROR;
+		}
+		ret = json_object_set_new(object->root, name, string);
+		if (ret != 0) {
+			json_decref(string);
+			DBG_ERR("Unable to add string [%s]\n", name);
+			return ret;
+		}
 	} else {
-		rc = json_object_set_new(object->root, name, json_null());
-	}
-	if (rc) {
-		DBG_ERR("Unable to set name [%s] value [%s]\n", name, value);
-		object->error = true;
+		ret = json_object_set_new(object->root, name, json_null());
+		if (ret != 0) {
+			DBG_ERR("Unable to add null string [%s]\n", name);
+			return ret;
+		}
 	}
+	return ret;
 }
 
 /*
@@ -464,13 +495,13 @@ void json_add_string(struct json_object *object,
  */
 void json_assert_is_array(struct json_object *array) {
 
-	if (array->error) {
+	if (json_is_invalid(array)) {
 		return;
 	}
 
 	if (json_is_array(array->root) == false) {
 		DBG_ERR("JSON object is not an array\n");
-		array->error = true;
+		array->valid = false;
 		return;
 	}
 }
@@ -479,43 +510,46 @@ void json_assert_is_array(struct json_object *array) {
  * @brief Add a JSON object to a JSON object.
  *
  * Add a JSON object named 'name' to the json object.
- * In the event of an error object will be invalidated.
  *
  * @param object the JSON object to be updated.
  * @param name the name.
  * @param value the value.
  *
+ * @return 0 the operation was successful
+ *        -1 the operation failed
+ *
  */
-void json_add_object(struct json_object *object,
-		     const char* name,
-		     struct json_object *value)
+int json_add_object(struct json_object *object,
+		    const char *name,
+		    struct json_object *value)
 {
-	int rc = 0;
+	int ret = 0;
 	json_t *jv = NULL;
 
-	if (object->error) {
-		return;
+	if (value != NULL && json_is_invalid(value)) {
+		DBG_ERR("Invalid JSON object [%s] supplied\n", name);
+		return JSON_ERROR;
 	}
-
-	if (value != NULL && value->error) {
-		object->error = true;
-		return;
+	if (json_is_invalid(object)) {
+		DBG_ERR("Unable to add object [%s], target object is invalid\n",
+			name);
+		return JSON_ERROR;
 	}
 
 	jv = value == NULL ? json_null() : value->root;
 
 	if (json_is_array(object->root)) {
-		rc = json_array_append_new(object->root, jv);
+		ret = json_array_append_new(object->root, jv);
 	} else if (json_is_object(object->root)) {
-		rc = json_object_set_new(object->root, name,  jv);
+		ret = json_object_set_new(object->root, name, jv);
 	} else {
 		DBG_ERR("Invalid JSON object type\n");
-		object->error = true;
+		ret = JSON_ERROR;
 	}
-	if (rc) {
+	if (ret != 0) {
 		DBG_ERR("Unable to add object [%s]\n", name);
-		object->error = true;
 	}
+	return ret;
 }
 
 /*
@@ -526,39 +560,57 @@ void json_add_object(struct json_object *object,
  * truncated if it is more than len characters long. If len is 0 the value
  * is encoded as a JSON null.
  *
- * In the event of an error object will be invalidated.
  *
  * @param object the JSON object to be updated.
  * @param name the name.
  * @param value the value.
  * @param len the maximum number of characters to be copied.
  *
+ * @return 0 the operation was successful
+ *        -1 the operation failed
+ *
  */
-void json_add_stringn(struct json_object *object,
-		      const char *name,
-		      const char *value,
-		      const size_t len)
+int json_add_stringn(struct json_object *object,
+		     const char *name,
+		     const char *value,
+		     const size_t len)
 {
 
-	int rc = 0;
-	if (object->error) {
-		return;
+	int ret = 0;
+	if (json_is_invalid(object)) {
+		DBG_ERR("Unable to add string [%s], target object is invalid\n",
+			name);
+		return JSON_ERROR;
 	}
 
 	if (value != NULL && len > 0) {
+		json_t *string = NULL;
 		char buffer[len+1];
+
 		strncpy(buffer, value, len);
 		buffer[len] = '\0';
-		rc = json_object_set_new(object->root,
-					 name,
-					 json_string(buffer));
+
+		string = json_string(buffer);
+		if (string == NULL) {
+			DBG_ERR("Unable to add string [%s], "
+				"could not create string object\n",
+				name);
+			return JSON_ERROR;
+		}
+		ret = json_object_set_new(object->root, name, string);
+		if (ret != 0) {
+			json_decref(string);
+			DBG_ERR("Unable to add string [%s]\n", name);
+			return ret;
+		}
 	} else {
-		rc = json_object_set_new(object->root, name, json_null());
-	}
-	if (rc) {
-		DBG_ERR("Unable to set name [%s] value [%s]\n", name, value);
-		object->error = true;
+		ret = json_object_set_new(object->root, name, json_null());
+		if (ret != 0) {
+			DBG_ERR("Unable to add null string [%s]\n", name);
+			return ret;
+		}
 	}
+	return ret;
 }
 
 /*
@@ -576,18 +628,45 @@ void json_add_stringn(struct json_object *object,
  * The minor version should change whenever a new attribute is added and for
  * minor bug fixes to an attributes content.
  *
- * In the event of an error object will be invalidated.
  *
  * @param object the JSON object to be updated.
  * @param major the major version number
  * @param minor the minor version number
+ *
+ * @return 0 the operation was successful
+ *        -1 the operation failed
  */
-void json_add_version(struct json_object *object, int major, int minor)
+int json_add_version(struct json_object *object, int major, int minor)
 {
-	struct json_object version = json_new_object();
-	json_add_int(&version, "major", major);
-	json_add_int(&version, "minor", minor);
-	json_add_object(object, "version", &version);
+	int ret = 0;
+	struct json_object version;
+
+	if (json_is_invalid(object)) {
+		DBG_ERR("Unable to add version, target object is invalid\n");
+		return JSON_ERROR;
+	}
+
+	version = json_new_object();
+	if (json_is_invalid(&version)) {
+		DBG_ERR("Unable to add version, failed to create object\n");
+		return JSON_ERROR;
+	}
+	ret = json_add_int(&version, "major", major);
+	if (ret != 0) {
+		json_free(&version);
+		return ret;
+	}
+	ret = json_add_int(&version, "minor", minor);
+	if (ret != 0) {
+		json_free(&version);
+		return ret;
+	}
+	ret = json_add_object(object, "version", &version);
+	if (ret != 0) {
+		json_free(&version);
+		return ret;
+	}
+	return ret;
 }
 
 /*
@@ -598,11 +677,13 @@ void json_add_version(struct json_object *object, int major, int minor)
  *
  * "timestamp":"2017-03-06T17:18:04.455081+1300"
  *
- * In the event of an error object will be invalidated.
  *
  * @param object the JSON object to be updated.
+ *
+ * @return 0 the operation was successful
+ *        -1 the operation failed
  */
-void json_add_timestamp(struct json_object *object)
+int json_add_timestamp(struct json_object *object)
 {
 	char buffer[40];	/* formatted time less usec and timezone */
 	char timestamp[65];	/* the formatted ISO 8601 time stamp	 */
@@ -610,9 +691,11 @@ void json_add_timestamp(struct json_object *object)
 	struct tm* tm_info;	/* current local time			 */
 	struct timeval tv;	/* current system time			 */
 	int r;			/* response code from gettimeofday	 */
+	int ret;		/* return code from json operations	*/
 
-	if (object->error) {
-		return;
+	if (json_is_invalid(object)) {
+		DBG_ERR("Unable to add time stamp, target object is invalid\n");
+		return JSON_ERROR;
 	}
 
 	r = gettimeofday(&tv, NULL);
@@ -620,15 +703,13 @@ void json_add_timestamp(struct json_object *object)
 		DBG_ERR("Unable to get time of day: (%d) %s\n",
 			errno,
 			strerror(errno));
-		object->error = true;
-		return;
+		return JSON_ERROR;
 	}
 
 	tm_info = localtime(&tv.tv_sec);
 	if (tm_info == NULL) {
 		DBG_ERR("Unable to determine local time\n");
-		object->error = true;
-		return;
+		return JSON_ERROR;
 	}
 
 	strftime(buffer, sizeof(buffer)-1, "%Y-%m-%dT%T", tm_info);
@@ -640,10 +721,13 @@ void json_add_timestamp(struct json_object *object)
 		buffer,
 		tv.tv_usec,
 		tz);
-	json_add_string(object, "timestamp", timestamp);
+	ret = json_add_string(object, "timestamp", timestamp);
+	if (ret != 0) {
+		DBG_ERR("Unable to add time stamp to JSON object\n");
+	}
+	return ret;
 }
 
-
 /*
  *@brief Add a tsocket_address to a JSON object
  *
@@ -651,35 +735,59 @@ void json_add_timestamp(struct json_object *object)
  *
  * "localAddress":"ipv6::::0"
  *
- * In the event of an error object will be invalidated.
  *
  * @param object the JSON object to be updated.
  * @param name the name.
  * @param address the tsocket_address.
  *
+ * @return 0 the operation was successful
+ *        -1 the operation failed
+ *
  */
-void json_add_address(struct json_object *object,
-		      const char *name,
-		      const struct tsocket_address *address)
+int json_add_address(struct json_object *object,
+		     const char *name,
+		     const struct tsocket_address *address)
 {
+	int ret = 0;
 
-	if (object->error) {
-		return;
+	if (json_is_invalid(object)) {
+		DBG_ERR("Unable to add address [%s], "
+			"target object is invalid\n",
+			name);
+		return JSON_ERROR;
 	}
+
 	if (address == NULL) {
-		int rc = json_object_set_new(object->root, name, json_null());
-		if (rc) {
-			DBG_ERR("Unable to set address [%s] to null\n", name);
-			object->error = true;
+		ret = json_object_set_new(object->root, name, json_null());
+		if (ret != 0) {
+			DBG_ERR("Unable to add null address [%s]\n", name);
+			return JSON_ERROR;
 		}
 	} else {
 		TALLOC_CTX *ctx = talloc_new(NULL);
 		char *s = NULL;
 
+		if (ctx == NULL) {
+			DBG_ERR("Out of memory adding address [%s]\n", name);
+			return JSON_ERROR;
+		}
+
 		s = tsocket_address_string(address, ctx);
-		json_add_string(object, name, s);
+		if (s == NULL) {
+			DBG_ERR("Out of memory adding address [%s]\n", name);
+			TALLOC_FREE(ctx);
+			return JSON_ERROR;
+		}
+		ret = json_add_string(object, name, s);
+		if (ret != 0) {
+			DBG_ERR(
+			    "Unable to add address [%s] value [%s]\n", name, s);
+			TALLOC_FREE(ctx);
+			return JSON_ERROR;
+		}
 		TALLOC_FREE(ctx);
 	}
+	return ret;
 }
 
 /*
@@ -689,33 +797,47 @@ void json_add_address(struct json_object *object,
  *
  * "sid":"S-1-5-18"
  *
- * In the event of an error object will be invalidated.
  *
  * @param object the JSON object to be updated.
  * @param name the name.
  * @param sid the sid
  *
+ * @return 0 the operation was successful
+ *        -1 the operation failed
+ *
  */
-void json_add_sid(struct json_object *object,
-		  const char *name,
-		  const struct dom_sid *sid)
+int json_add_sid(struct json_object *object,
+		 const char *name,
+		 const struct dom_sid *sid)
 {
+	int ret = 0;
 
-	if (object->error) {
-		return;
+	if (json_is_invalid(object)) {
+		DBG_ERR("Unable to add SID [%s], "
+			"target object is invalid\n",
+			name);
+		return JSON_ERROR;
 	}
+
 	if (sid == NULL) {
-		int rc = json_object_set_new(object->root, name, json_null());
-		if (rc) {
-			DBG_ERR("Unable to set SID [%s] to null\n", name);
-			object->error = true;
+		ret = json_object_set_new(object->root, name, json_null());
+		if (ret != 0) {
+			DBG_ERR("Unable to add null SID [%s]\n", name);
+			return ret;
 		}
 	} else {
 		char sid_buf[DOM_SID_STR_BUFLEN];
 
 		dom_sid_string_buf(sid, sid_buf, sizeof(sid_buf));
-		json_add_string(object, name, sid_buf);
+		ret = json_add_string(object, name, sid_buf);
+		if (ret != 0) {
+			DBG_ERR("Unable to add SID [%s] value [%s]\n",
+				name,
+				sid_buf);
+			return ret;
+		}
 	}
+	return ret;
 }
 
 /*
@@ -725,46 +847,59 @@ void json_add_sid(struct json_object *object,
  *
  * "guid":"1fb9f2ee-2a4d-4bf8-af8b-cb9d4529a9ab"
  *
- * In the event of an error object will be invalidated.
  *
  * @param object the JSON object to be updated.
  * @param name the name.
  * @param guid the guid.
  *
+ * @return 0 the operation was successful
+ *        -1 the operation failed
+ *
  *
  */
-void json_add_guid(struct json_object *object,
-		   const char *name,
-		   const struct GUID *guid)
+int json_add_guid(struct json_object *object,
+		  const char *name,
+		  const struct GUID *guid)
 {
 
+	int ret = 0;
 
-	if (object->error) {
-		return;
+	if (json_is_invalid(object)) {
+		DBG_ERR("Unable to add GUID [%s], "
+			"target object is invalid\n",
+			name);
+		return JSON_ERROR;
 	}
+
 	if (guid == NULL) {
-		int rc = json_object_set_new(object->root, name, json_null());
-		if (rc) {
-			DBG_ERR("Unable to set GUID [%s] to null\n", name);
-			object->error = true;
+		ret = json_object_set_new(object->root, name, json_null());
+		if (ret != 0) {
+			DBG_ERR("Unable to add null GUID [%s]\n", name);
+			return ret;
 		}
 	} else {
 		char *guid_str;
 		struct GUID_txt_buf guid_buff;
 
 		guid_str = GUID_buf_string(guid, &guid_buff);
-		json_add_string(object, name, guid_str);
+		ret = json_add_string(object, name, guid_str);
+		if (ret != 0) {
+			DBG_ERR("Unable to guid GUID [%s] value [%s]\n",
+				name,
+				guid_str);
+			return ret;
+		}
 	}
+	return ret;
 }
 
-
 /*
  * @brief Convert a JSON object into a string
  *
  * Convert the jsom object into a string suitable for printing on a log line,
  * i.e. with no embedded line breaks.
  *
- * If the object is invalid it returns NULL.
+ * If the object is invalid it logs an error and returns NULL.
  *
  * @param mem_ctx the talloc memory context owning the returned string
  * @param object the json object.
@@ -772,13 +907,17 @@ void json_add_guid(struct json_object *object,
  * @return A string representation of the object or NULL if the object
  *         is invalid.
  */
-char *json_to_string(TALLOC_CTX *mem_ctx,
-		     struct json_object *object)
+char *json_to_string(TALLOC_CTX *mem_ctx, struct json_object *object)
 {
 	char *json = NULL;
 	char *json_string = NULL;
 
-	if (object->error) {
+	if (json_is_invalid(object)) {
+		DBG_ERR("Invalid JSON object, unable to convert to string\n");
+		return NULL;
+	}
+
+	if (object->root == NULL) {
 		return NULL;
 	}
 
@@ -813,15 +952,23 @@ char *json_to_string(TALLOC_CTX *mem_ctx,
  *
  * @return The array object, will be created if it did not exist.
  */
-struct json_object json_get_array(struct json_object *object,
-				  const char* name)
+struct json_object json_get_array(struct json_object *object, const char *name)
 {
 
-	struct json_object array = json_new_array();
+	struct json_object array = json_empty_object;
 	json_t *a = NULL;
+	int ret = 0;
+
+	if (json_is_invalid(object)) {
+		DBG_ERR("Invalid JSON object, unable to get array [%s]\n",
+			name);
+		json_free(&array);
+		return array;
+	}
 
-	if (object->error) {
-		array.error = true;
+	array = json_new_array();
+	if (json_is_invalid(&array)) {
+		DBG_ERR("Unable to create new array for [%s]\n", name);
 		return array;
 	}
 
@@ -829,7 +976,13 @@ struct json_object json_get_array(struct json_object *object,
 	if (a == NULL) {
 		return array;
 	}
-	json_array_extend(array.root, a);
+
+	ret = json_array_extend(array.root, a);
+	if (ret != 0) {
+		DBG_ERR("Unable to get array [%s]\n", name);
+		json_free(&array);
+		return array;
+	}
 
 	return array;
 }
@@ -844,15 +997,17 @@ struct json_object json_get_array(struct json_object *object,
  *
  * @return The object, will be created if it did not exist.
  */
-struct json_object json_get_object(struct json_object *object,
-				   const char* name)
+struct json_object json_get_object(struct json_object *object, const char *name)
 {
 
 	struct json_object o = json_new_object();
 	json_t *v = NULL;
+	int ret = 0;
 
-	if (object->error) {
-		o.error = true;
+	if (json_is_invalid(object)) {
+		DBG_ERR("Invalid JSON object, unable to get object [%s]\n",
+			name);
+		json_free(&o);
 		return o;
 	}
 
@@ -860,8 +1015,12 @@ struct json_object json_get_object(struct json_object *object,
 	if (v == NULL) {
 		return o;
 	}
-	json_object_update(o.root, v);
-
+	ret = json_object_update(o.root, v);
+	if (ret != 0) {
+		DBG_ERR("Unable to get object [%s]\n", name);
+		json_free(&o);
+		return o;
+	}
 	return o;
 }
 #endif
diff --git a/lib/audit_logging/audit_logging.h b/lib/audit_logging/audit_logging.h
index 4af743a4102..84738d2bb93 100644
--- a/lib/audit_logging/audit_logging.h
+++ b/lib/audit_logging/audit_logging.h
@@ -16,7 +16,8 @@
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
-
+#ifndef _AUDIT_LOGGING_H_
+#define _AUDIT_LOGGING_H_
 #include <talloc.h>
 #include "lib/messaging/irpc.h"
 #include "lib/tsocket/tsocket.h"
@@ -35,8 +36,11 @@ void audit_log_human_text(const char *prefix,
  */
 struct json_object {
 	json_t *root;
-	bool error;
+	bool valid;
 };
+extern const struct json_object json_empty_object;
+
+#define JSON_ERROR -1
 
 void audit_log_json(const char *prefix,
 		    struct json_object *message,
@@ -52,35 +56,31 @@ void json_free(struct json_object *object);
 void json_assert_is_array(struct json_object *array);
 bool json_is_invalid(struct json_object *object);
 
-void json_add_int(struct json_object *object,
-		  const char* name,
-		  const int value);
-void json_add_bool(struct json_object *object,
-		   const char* name,
-		   const bool value);
-void json_add_string(struct json_object *object,
-		     const char* name,
-		     const char* value);
-void json_add_object(struct json_object *object,
-		     const char* name,
-		     struct json_object *value);
-void json_add_stringn(struct json_object *object,
-		      const char *name,
-		      const char *value,
-		      const size_t len);
-void json_add_version(struct json_object *object,
-		      int major,
-		      int minor);
-void json_add_timestamp(struct json_object *object);
-void json_add_address(struct json_object *object,
-		      const char *name,
-		      const struct tsocket_address *address);
-void json_add_sid(struct json_object *object,
+int json_add_int(struct json_object *object, const char *name, const int value);
+int json_add_bool(struct json_object *object,
 		  const char *name,
-		  const struct dom_sid *sid);
-void json_add_guid(struct json_object *object,
-		   const char *name,
-		   const struct GUID *guid);
+		  const bool value);
+int json_add_string(struct json_object *object,
+		    const char *name,
+		    const char *value);
+int json_add_object(struct json_object *object,
+		    const char *name,
+		    struct json_object *value);
+int json_add_stringn(struct json_object *object,
+		     const char *name,
+		     const char *value,
+		     const size_t len);
+int json_add_version(struct json_object *object, int major, int minor);
+int json_add_timestamp(struct json_object *object);
+int json_add_address(struct json_object *object,
+		     const char *name,
+		     const struct tsocket_address *address);
+int json_add_sid(struct json_object *object,
+		 const char *name,
+		 const struct dom_sid *sid);
+int json_add_guid(struct json_object *object,
+		  const char *name,
+		  const struct GUID *guid);
 
 struct json_object json_get_array(struct json_object *object,
 				  const char* name);
@@ -89,3 +89,4 @@ struct json_object json_get_object(struct json_object *object,
 char *json_to_string(TALLOC_CTX *mem_ctx,
 		     struct json_object *object);
 #endif
+#endif
diff --git a/lib/audit_logging/tests/audit_logging_test.c b/lib/audit_logging/tests/audit_logging_test.c
index 26875c98944..07c52eada39 100644
--- a/lib/audit_logging/tests/audit_logging_test.c
+++ b/lib/audit_logging/tests/audit_logging_test.c
@@ -64,12 +64,15 @@ static void test_json_add_int(void **state)
 	struct json_object object;
 	struct json_t *value = NULL;
 	double n;
+	int rc = 0;
 
 	object = json_new_object();
-	json_add_int(&object, "positive_one", 1);
-	json_add_int(&object, "zero", 0);
-	json_add_int(&object, "negative_one", -1);
-
+	rc = json_add_int(&object, "positive_one", 1);
+	assert_int_equal(0, rc);
+	rc = json_add_int(&object, "zero", 0);
+	assert_int_equal(0, rc);
+	rc = json_add_int(&object, "negative_one", -1);
+	assert_int_equal(0, rc);
 
 	assert_int_equal(3, json_object_size(object.root));
 
@@ -88,18 +91,27 @@ static void test_json_add_int(void **state)
 	n = json_number_value(value);
 	assert_true(n == -1.0);
 
+	object.valid = false;
+	rc = json_add_int(&object, "should fail 1", 0xf1);
+	assert_int_equal(JSON_ERROR, rc);
+
 	json_free(&object);
+
+	rc = json_add_int(&object, "should fail 2", 0xf2);
+	assert_int_equal(JSON_ERROR, rc);
 }
 
 static void test_json_add_bool(void **state)
 {
 	struct json_object object;
 	struct json_t *value = NULL;
+	int rc = 0;
 
 	object = json_new_object();
-	json_add_bool(&object, "true", true);
-	json_add_bool(&object, "false", false);
-
+	rc = json_add_bool(&object, "true", true);
+	assert_int_equal(0, rc);
+	rc = json_add_bool(&object, "false", false);
+	assert_int_equal(0, rc);
 
 	assert_int_equal(2, json_object_size(object.root));
 
@@ -111,7 +123,14 @@ static void test_json_add_bool(void **state)
 	assert_true(json_is_boolean(value));
 	assert_true(value == json_false());
 
+	object.valid = false;
+	rc = json_add_bool(&object, "should fail 1", true);
+	assert_int_equal(JSON_ERROR, rc);
+
 	json_free(&object);
+
+	rc = json_add_bool(&object, "should fail 2", false);
+	assert_int_equal(JSON_ERROR, rc);
 }
 
 static void test_json_add_string(void **state)
@@ -119,13 +138,15 @@ static void test_json_add_string(void **state)
 	struct json_object object;
 	struct json_t *value = NULL;
 	const char *s = NULL;
+	int rc = 0;
 
 	object = json_new_object();
-	json_add_string(&object, "null", NULL);
-	json_add_string(&object, "empty", "");
-	json_add_string(&object, "name", "value");
-
-
+	rc = json_add_string(&object, "null", NULL);
+	assert_int_equal(0, rc);
+	rc = json_add_string(&object, "empty", "");
+	assert_int_equal(0, rc);
+	rc = json_add_string(&object, "name", "value");
+	assert_int_equal(0, rc);
 
 	assert_int_equal(3, json_object_size(object.root));
 
@@ -141,21 +162,32 @@ static void test_json_add_string(void **state)
 	assert_true(json_is_string(value));
 	s = json_string_value(value);
 	assert_string_equal("value", s);
+
+	object.valid = false;
+	rc = json_add_string(&object, "should fail 1", "A value");
+	assert_int_equal(JSON_ERROR, rc);
+
 	json_free(&object);
+
+	rc = json_add_string(&object, "should fail 2", "Another value");
+	assert_int_equal(JSON_ERROR, rc);
 }
 
 static void test_json_add_object(void **state)
 {
 	struct json_object object;
 	struct json_object other;
+	struct json_object after;
+	struct json_object invalid = json_empty_object;
 	struct json_t *value = NULL;
+	int rc = 0;
 
 	object = json_new_object();
 	other  = json_new_object();
-	json_add_object(&object, "null", NULL);
-	json_add_object(&object, "other", &other);
-
-
+	rc = json_add_object(&object, "null", NULL);
+	assert_int_equal(0, rc);
+	rc = json_add_object(&object, "other", &other);
+	assert_int_equal(0, rc);
 
 	assert_int_equal(2, json_object_size(object.root));
 
@@ -166,7 +198,20 @@ static void test_json_add_object(void **state)
 	assert_true(json_is_object(value));
 	assert_ptr_equal(other.root, value);
 
+	rc = json_add_object(&object, "invalid", &invalid);
+	assert_int_equal(JSON_ERROR, rc);
+
+	object.valid = false;
+	after = json_new_object();
+	rc = json_add_object(&object, "after", &after);
+	assert_int_equal(JSON_ERROR, rc);
+
 	json_free(&object);
+
+	rc = json_add_object(&object, "after", &after);
+	assert_int_equal(JSON_ERROR, rc);
+
+	json_free(&after);
 }
 
 static void test_json_add_to_array(void **state)
@@ -175,7 +220,10 @@ static void test_json_add_to_array(void **state)
 	struct json_object o1;
 	struct json_object o2;
 	struct json_object o3;
+	struct json_object after;
+	struct json_object invalid = json_empty_object;
 	struct json_t *value = NULL;
+	int rc = 0;
 
 	array = json_new_array();
 	assert_true(json_is_array(array.root));
@@ -184,10 +232,14 @@ static void test_json_add_to_array(void **state)
 	o2 = json_new_object();
 	o3 = json_new_object();
 
-	json_add_object(&array, NULL, &o3);
-	json_add_object(&array, "", &o2);
-	json_add_object(&array, "will-be-ignored", &o1);
-	json_add_object(&array, NULL, NULL);
+	rc = json_add_object(&array, NULL, &o3);
+	assert_int_equal(0, rc);
+	rc = json_add_object(&array, "", &o2);
+	assert_int_equal(0, rc);
+	rc = json_add_object(&array, "will-be-ignored", &o1);
+	assert_int_equal(0, rc);
+	rc = json_add_object(&array, NULL, NULL);
+	assert_int_equal(0, rc);
 
 	assert_int_equal(4, json_array_size(array.root));
 
@@ -203,8 +255,20 @@ static void test_json_add_to_array(void **state)
 	value = json_array_get(array.root, 3);
 	assert_true(json_is_null(value));
 
+	rc = json_add_object(&array, "invalid", &invalid);
+	assert_int_equal(JSON_ERROR, rc);
+
+	array.valid = false;
+	after = json_new_object();
+	rc = json_add_object(&array, "after", &after);
+	assert_int_equal(JSON_ERROR, rc);
+
 	json_free(&array);
 
+	rc = json_add_object(&array, "after", &after);
+	assert_int_equal(JSON_ERROR, rc);
+
+	json_free(&after);
 }
 
 static void test_json_add_timestamp(void **state)
@@ -224,7 +288,8 @@ static void test_json_add_timestamp(void **state)
 
 	object = json_new_object();
 	before = time(NULL);
-	json_add_timestamp(&object);
+	rc = json_add_timestamp(&object);
+	assert_int_equal(0, rc);
 	after = time(NULL);
 
 	ts = json_object_get(object.root, "timestamp");
@@ -263,7 +328,14 @@ static void test_json_add_timestamp(void **state)
 	assert_true(difftime(actual, before) >= 0);
 	assert_true(difftime(after, actual) >= 0);
 
+	object.valid = false;
+	rc = json_add_timestamp(&object);
+	assert_int_equal(JSON_ERROR, rc);
+
 	json_free(&object);
+
+	rc = json_add_timestamp(&object);
+	assert_int_equal(JSON_ERROR, rc);
 }
 
 static void test_json_add_stringn(void **state)
@@ -271,17 +343,26 @@ static void test_json_add_stringn(void **state)
 	struct json_object object;
 	struct json_t *value = NULL;
 	const char *s = NULL;
+	int rc = 0;
 
 	object = json_new_object();
-	json_add_stringn(&object, "null", NULL, 10);
-	json_add_stringn(&object, "null-zero-len", NULL, 0);
-	json_add_stringn(&object, "empty", "", 1);
-	json_add_stringn(&object, "empty-zero-len", "", 0);
-	json_add_stringn(&object, "value-less-than-len", "123456", 7);
-	json_add_stringn(&object, "value-greater-than-len", "abcd", 3);
-	json_add_stringn(&object, "value-equal-len", "ZYX", 3);
-	json_add_stringn(&object, "value-len-is-zero", "this will be null", 0);
-
+	rc = json_add_stringn(&object, "null", NULL, 10);
+	assert_int_equal(0, rc);
+	rc = json_add_stringn(&object, "null-zero-len", NULL, 0);
+	assert_int_equal(0, rc);
+	rc = json_add_stringn(&object, "empty", "", 1);
+	assert_int_equal(0, rc);
+	rc = json_add_stringn(&object, "empty-zero-len", "", 0);
+	assert_int_equal(0, rc);
+	rc = json_add_stringn(&object, "value-less-than-len", "123456", 7);
+	assert_int_equal(0, rc);
+	rc = json_add_stringn(&object, "value-greater-than-len", "abcd", 3);
+	assert_int_equal(0, rc);
+	rc = json_add_stringn(&object, "value-equal-len", "ZYX", 3);
+	assert_int_equal(0, rc);
+	rc = json_add_stringn(
+	    &object, "value-len-is-zero", "this will be null", 0);
+	assert_int_equal(0, rc);
 
 	assert_int_equal(8, json_object_size(object.root));
 
@@ -314,7 +395,14 @@ static void test_json_add_stringn(void **state)
 	value = json_object_get(object.root, "value-len-is-zero");
 	assert_true(json_is_null(value));
 
+	object.valid = false;
+	rc = json_add_stringn(&object, "fail-01", "xxxxxxx", 1);
+	assert_int_equal(JSON_ERROR, rc);
+
 	json_free(&object);
+
+	rc = json_add_stringn(&object, "fail-02", "xxxxxxx", 1);
+	assert_int_equal(JSON_ERROR, rc);
 }
 
 static void test_json_add_version(void **state)
@@ -323,9 +411,11 @@ static void test_json_add_version(void **state)
 	struct json_t *version = NULL;
 	struct json_t *v = NULL;
 	double n;
+	int rc;
 
 	object = json_new_object();
-	json_add_version(&object, 3, 1);
+	rc = json_add_version(&object, 3, 1);
+	assert_int_equal(0, rc);
 
 	assert_int_equal(1, json_object_size(object.root));
 
@@ -343,7 +433,14 @@ static void test_json_add_version(void **state)
 	n = json_number_value(v);
 	assert_true(n == 1.0);
 
+	object.valid = false;
+	rc = json_add_version(&object, 3, 1);
+	assert_int_equal(JSON_ERROR, rc);
+
 	json_free(&object);
+
+	rc = json_add_version(&object, 3, 1);
+	assert_int_equal(JSON_ERROR, rc);
 }
 
 static void test_json_add_address(void **state)
@@ -353,6 +450,8 @@ static void test_json_add_address(void **state)
 	struct tsocket_address *ip4  = NULL;
 	struct tsocket_address *ip6  = NULL;
 	struct tsocket_address *pipe = NULL;
+
+	struct tsocket_address *after = NULL;
 	const char *s = NULL;
 	int rc;
 
@@ -360,7 +459,8 @@ static void test_json_add_address(void **state)
 
 	object = json_new_object();
 
-	json_add_address(&object, "null", NULL);
+	rc = json_add_address(&object, "null", NULL);
+	assert_int_equal(0, rc);
 
 	rc = tsocket_address_inet_from_strings(
 		ctx,
@@ -369,7 +469,8 @@ static void test_json_add_address(void **state)
 		21,
 		&ip4);
 	assert_int_equal(0, rc);
-	json_add_address(&object, "ip4", ip4);
+	rc = json_add_address(&object, "ip4", ip4);
+	assert_int_equal(0, rc);
 
 	rc = tsocket_address_inet_from_strings(
 		ctx,
@@ -378,11 +479,13 @@ static void test_json_add_address(void **state)
 		42,
 		&ip6);
 	assert_int_equal(0, rc);
-	json_add_address(&object, "ip6", ip6);
+	rc = json_add_address(&object, "ip6", ip6);
+	assert_int_equal(0, rc);
 
 	rc = tsocket_address_unix_from_path(ctx, "/samba/pipe", &pipe);
 	assert_int_equal(0, rc);
-	json_add_address(&object, "pipe", pipe);
+	rc = json_add_address(&object, "pipe", pipe);
+	assert_int_equal(0, rc);
 
 	assert_int_equal(4, json_object_size(object.root));
 
@@ -404,7 +507,18 @@ static void test_json_add_address(void **state)
 	s = json_string_value(value);
 	assert_string_equal("unix:/samba/pipe", s);
 
+	object.valid = false;
+	rc = tsocket_address_inet_from_strings(
+	    ctx, "ip", "127.0.0.11", 23, &after);
+	assert_int_equal(0, rc);
+	rc = json_add_address(&object, "invalid_object", after);
+	assert_int_equal(JSON_ERROR, rc);
+
 	json_free(&object);
+
+	rc = json_add_address(&object, "freed object", after);
+	assert_int_equal(JSON_ERROR, rc);
+
 	TALLOC_FREE(ctx);
 }
 
@@ -415,14 +529,16 @@ static void test_json_add_sid(void **state)
 	const char *SID = "S-1-5-21-2470180966-3899876309-2637894779";
 	struct dom_sid sid;
 	const char *s = NULL;
-
+	int rc;
 
 	object = json_new_object();
 
-	json_add_sid(&object, "null", NULL);
+	rc = json_add_sid(&object, "null", NULL);
+	assert_int_equal(0, rc);
 
 	assert_true(string_to_sid(&sid, SID));
-	json_add_sid(&object, "sid", &sid);
+	rc = json_add_sid(&object, "sid", &sid);
+	assert_int_equal(0, rc);
 
 	assert_int_equal(2, json_object_size(object.root));
 
@@ -433,7 +549,15 @@ static void test_json_add_sid(void **state)
 	assert_true(json_is_string(value));
 	s = json_string_value(value);
 	assert_string_equal(SID, s);
+
+	object.valid = false;
+	rc = json_add_sid(&object, "invalid_object", &sid);
+	assert_int_equal(JSON_ERROR, rc);
+
 	json_free(&object);
+
+	rc = json_add_sid(&object, "freed_object", &sid);
+	assert_int_equal(JSON_ERROR, rc);
 }
 
 static void test_json_add_guid(void **state)
@@ -444,15 +568,17 @@ static void test_json_add_guid(void **state)
 	struct GUID guid;
 	const char *s = NULL;
 	NTSTATUS status;
-
+	int rc;
 
 	object = json_new_object();
 
-	json_add_guid(&object, "null", NULL);
+	rc = json_add_guid(&object, "null", NULL);
+	assert_int_equal(0, rc);
 
 	status = GUID_from_string(GUID, &guid);
 	assert_true(NT_STATUS_IS_OK(status));
-	json_add_guid(&object, "guid", &guid);
+	rc = json_add_guid(&object, "guid", &guid);
+	assert_int_equal(0, rc);
 
 	assert_int_equal(2, json_object_size(object.root));
 
@@ -464,7 +590,14 @@ static void test_json_add_guid(void **state)
 	s = json_string_value(value);
 	assert_string_equal(GUID, s);
 
+	object.valid = false;
+	rc = json_add_guid(&object, "invalid_object", &guid);
+	assert_int_equal(JSON_ERROR, rc);
+
 	json_free(&object);
+
+	rc = json_add_guid(&object, "freed_object", &guid);
+	assert_int_equal(JSON_ERROR, rc);
 }
 
 static void test_json_to_string(void **state)
@@ -475,12 +608,7 @@ static void test_json_to_string(void **state)
 	TALLOC_CTX *ctx = talloc_new(NULL);
 
 	object = json_new_object();
-	object.error = true;
-
-	s = json_to_string(ctx, &object);
-	assert_null(s);
 
-	object.error = false;
 	s = json_to_string(ctx, &object);
 	assert_string_equal("{}", s);
 	TALLOC_FREE(s);
@@ -490,7 +618,17 @@ static void test_json_to_string(void **state)
 	assert_string_equal("{\"name\": \"value\"}", s);
 	TALLOC_FREE(s);
 
+	object.valid = false;
+	s = json_to_string(ctx, &object);
+	assert_null(s);
+
 	json_free(&object);
+
+	object.valid = true;
+	object.root = NULL;
+
+	s = json_to_string(ctx, &object);
+	assert_null(s);
 	TALLOC_FREE(ctx);
 }
 
@@ -507,7 +645,7 @@ static void test_json_get_array(void **state)
 	object = json_new_object();
 
 	array = json_get_array(&object, "not-there");
-	assert_false(array.error);
+	assert_true(array.valid);
 	assert_non_null(array.root);
 	assert_true(json_is_array(array.root));
 	json_free(&array);
@@ -518,7 +656,7 @@ static void test_json_get_array(void **state)
 	json_add_object(&object, "stored_array", &stored_array);
 
 	array = json_get_array(&object, "stored_array");
-	assert_false(array.error);
+	assert_true(array.valid);
 	assert_non_null(array.root);
 	assert_true(json_is_array(array.root));
 
@@ -542,7 +680,7 @@ static void test_json_get_array(void **state)
 	assert_true(json_is_array(array.root));
 	o2 = json_new_object();
 	json_add_string(&o2, "value", "value-two");
-	assert_false(o2.error);
+	assert_true(o2.valid);
 	json_add_object(&array, NULL, &o2);
 	assert_true(json_is_array(array.root));
 	json_add_object(&object, "stored_array", &array);
@@ -551,7 +689,7 @@ static void test_json_get_array(void **state)
 	array = json_get_array(&object, "stored_array");
 	assert_non_null(array.root);
 	assert_true(json_is_array(array.root));
-	assert_false(array.error);
+	assert_true(array.valid);
 	assert_true(json_is_array(array.root));
 
 	assert_int_equal(2, json_array_size(array.root));
@@ -577,6 +715,10 @@ static void test_json_get_array(void **state)
 
 	json_free(&array);
 	json_free(&object);
+
+	array = json_get_array(&object, "stored_array");
+	assert_false(array.valid);
+	json_free(&array);
 }
 
 static void test_json_get_object(void **state)
@@ -590,7 +732,7 @@ static void test_json_get_object(void **state)
 	object = json_new_object();
 
 	o1 = json_get_object(&object, "not-there");
-	assert_false(o1.error);
+	assert_true(o1.valid);
 	assert_non_null(o1.root);
 	assert_true(json_is_object(o1.root));
 	json_free(&o1);
@@ -600,7 +742,7 @@ static void test_json_get_object(void **state)
 	json_add_object(&object, "stored_object", &o1);
 
 	o2 = json_get_object(&object, "stored_object");
-	assert_false(o2.error);
+	assert_true(o2.valid);
 	assert_non_null(o2.root);
 	assert_true(json_is_object(o2.root));
 
@@ -615,7 +757,7 @@ static void test_json_get_object(void **state)
 
 
 	o3 = json_get_object(&object, "stored_object");
-	assert_false(o3.error);
+	assert_true(o3.valid);
 	assert_non_null(o3.root);
 	assert_true(json_is_object(o3.root));
 
@@ -627,6 +769,10 @@ static void test_json_get_object(void **state)
 
 	json_free(&o3);
 	json_free(&object);
+
+	o3 = json_get_object(&object, "stored_object");
+	assert_false(o3.valid);
+	json_free(&o3);
 }
 
 static void test_audit_get_timestamp(void **state)
diff --git a/source4/dsdb/samdb/ldb_modules/audit_log.c b/source4/dsdb/samdb/ldb_modules/audit_log.c
index 581f2f235eb..dd714bca4e1 100644
--- a/source4/dsdb/samdb/ldb_modules/audit_log.c
+++ b/source4/dsdb/samdb/ldb_modules/audit_log.c
@@ -176,6 +176,7 @@ static const char *get_password_action(
  *
  * @return the generated JSON object, should be freed with json_free.
  *
+ *
  */
 static struct json_object operation_json(
 	struct ldb_module *module,
@@ -185,8 +186,8 @@ static struct json_object operation_json(
 	struct ldb_context *ldb = NULL;
 	const struct dom_sid *sid = NULL;
 	bool as_system = false;
-	struct json_object wrapper;
-	struct json_object audit;
+	struct json_object wrapper = json_empty_object;
+	struct json_object audit = json_empty_object;
 	const struct tsocket_address *remote = NULL;
 	const char *dn = NULL;
 	const char* operation = NULL;
@@ -195,6 +196,7 @@ static struct json_object operation_json(
 	struct audit_private *audit_private
 		= talloc_get_type_abort(ldb_module_get_private(module),
 					struct audit_private);
+	int rc = 0;
 
 	ldb = ldb_module_get_ctx(module);
 
@@ -213,18 +215,50 @@ static struct json_object operation_json(
 	operation = dsdb_audit_get_operation_name(request);
 
 	audit = json_new_object();
-	json_add_version(&audit, OPERATION_MAJOR, OPERATION_MINOR);
-	json_add_int(&audit, "statusCode", reply->error);
-	json_add_string(&audit, "status", ldb_strerror(reply->error));
-	json_add_string(&audit, "operation", operation);
-	json_add_address(&audit, "remoteAddress", remote);
-	json_add_bool(&audit, "performedAsSystem", as_system);
-	json_add_sid(&audit, "userSid", sid);
-	json_add_string(&audit, "dn", dn);
-	json_add_guid(&audit,
-		      "transactionId",
-		      &audit_private->transaction_guid);
-	json_add_guid(&audit, "sessionId", unique_session_token);
+	if (json_is_invalid(&audit)) {
+		goto failure;
+	}
+	rc = json_add_version(&audit, OPERATION_MAJOR, OPERATION_MINOR);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_int(&audit, "statusCode", reply->error);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "status", ldb_strerror(reply->error));
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "operation", operation);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_address(&audit, "remoteAddress", remote);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_bool(&audit, "performedAsSystem", as_system);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_sid(&audit, "userSid", sid);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "dn", dn);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_guid(
+	    &audit, "transactionId", &audit_private->transaction_guid);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_guid(&audit, "sessionId", unique_session_token);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	message = dsdb_audit_get_message(request);
 	if (message != NULL) {
@@ -232,13 +266,46 @@ static struct json_object operation_json(
 			dsdb_audit_attributes_json(
 				request->operation,
 				message);
-		json_add_object(&audit, "attributes", &attributes);
+		if (json_is_invalid(&attributes)) {
+			goto failure;
+		}
+		rc = json_add_object(&audit, "attributes", &attributes);
+		if (rc != 0) {
+			goto failure;
+		}
 	}
 
 	wrapper = json_new_object();
-	json_add_timestamp(&wrapper);
-	json_add_string(&wrapper, "type", OPERATION_JSON_TYPE);
-	json_add_object(&wrapper, OPERATION_JSON_TYPE, &audit);
+	if (json_is_invalid(&wrapper)) {
+		goto failure;
+	}
+	rc = json_add_timestamp(&wrapper);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&wrapper, "type", OPERATION_JSON_TYPE);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_object(&wrapper, OPERATION_JSON_TYPE, &audit);
+	if (rc != 0) {
+		goto failure;
+	}
+	return wrapper;
+
+failure:
+	/*
+	 * On a failure audit will not have been added to wrapper so it
+	 * needs to free it to avoid a leak.
+	 *
+	 * wrapper is freed to invalidate it as it will have only been
+	 * partially constructed and may be inconsistent.
+	 *
+	 * All the json manipulation routines handle a freed object correctly
+	 */
+	json_free(&audit);
+	json_free(&wrapper);
+	DBG_ERR("Unable to create ldb operation JSON audit message\n");
 	return wrapper;
 }
 
@@ -252,6 +319,7 @@ static struct json_object operation_json(
  * @paran reply the result of the operation
  *
  * @return the generated JSON object, should be freed with json_free.
+ *         NULL if there was an error generating the message.
  *
  */
 static struct json_object replicated_update_json(
@@ -259,8 +327,8 @@ static struct json_object replicated_update_json(
 	const struct ldb_request *request,
 	const struct ldb_reply *reply)
 {
-	struct json_object wrapper;
-	struct json_object audit;
+	struct json_object wrapper = json_empty_object;
+	struct json_object audit = json_empty_object;
 	struct audit_private *audit_private
 		= talloc_get_type_abort(ldb_module_get_private(module),
 					struct audit_private);
@@ -269,35 +337,93 @@ static struct json_object replicated_update_json(
 		struct dsdb_extended_replicated_objects);
 	const char *partition_dn = NULL;
 	const char *error = NULL;
+	int rc = 0;
 
 	partition_dn = ldb_dn_get_linearized(ro->partition_dn);
 	error = get_friendly_werror_msg(ro->error);
 
 	audit = json_new_object();
-	json_add_version(&audit, REPLICATION_MAJOR, REPLICATION_MINOR);
-	json_add_int(&audit, "statusCode", reply->error);
-	json_add_string(&audit, "status", ldb_strerror(reply->error));
-	json_add_guid(&audit,
-		      "transactionId",
-		      &audit_private->transaction_guid);
-	json_add_int(&audit, "objectCount", ro->num_objects);
-	json_add_int(&audit, "linkCount", ro->linked_attributes_count);
-	json_add_string(&audit, "partitionDN", partition_dn);
-	json_add_string(&audit, "error", error);
-	json_add_int(&audit, "errorCode", W_ERROR_V(ro->error));
-	json_add_guid(
-		&audit,
-		"sourceDsa",
-		&ro->source_dsa->source_dsa_obj_guid);
-	json_add_guid(
-		&audit,
-		"invocationId",
-		&ro->source_dsa->source_dsa_invocation_id);
+	if (json_is_invalid(&audit)) {
+		goto failure;
+	}
+	rc = json_add_version(&audit, REPLICATION_MAJOR, REPLICATION_MINOR);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_int(&audit, "statusCode", reply->error);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "status", ldb_strerror(reply->error));
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_guid(
+	    &audit, "transactionId", &audit_private->transaction_guid);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_int(&audit, "objectCount", ro->num_objects);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_int(&audit, "linkCount", ro->linked_attributes_count);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "partitionDN", partition_dn);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "error", error);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_int(&audit, "errorCode", W_ERROR_V(ro->error));
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_guid(
+	    &audit, "sourceDsa", &ro->source_dsa->source_dsa_obj_guid);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_guid(
+	    &audit, "invocationId", &ro->source_dsa->source_dsa_invocation_id);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	wrapper = json_new_object();
-	json_add_timestamp(&wrapper);
-	json_add_string(&wrapper, "type", REPLICATION_JSON_TYPE);
-	json_add_object(&wrapper, REPLICATION_JSON_TYPE, &audit);
+	if (json_is_invalid(&wrapper)) {
+		goto failure;
+	}
+	rc = json_add_timestamp(&wrapper);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&wrapper, "type", REPLICATION_JSON_TYPE);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_object(&wrapper, REPLICATION_JSON_TYPE, &audit);
+	if (rc != 0) {
+		goto failure;
+	}
+	return wrapper;
+failure:
+	/*
+	 * On a failure audit will not have been added to wrapper so it
+	 * needs to be freed it to avoid a leak.
+	 *
+	 * wrapper is freed to invalidate it as it will have only been
+	 * partially constructed and may be inconsistent.
+	 *
+	 * All the json manipulation routines handle a freed object correctly
+	 */
+	json_free(&audit);
+	json_free(&wrapper);
+	DBG_ERR("Unable to create replicated update JSON audit message\n");
 	return wrapper;
 }
 
@@ -321,16 +447,16 @@ static struct json_object password_change_json(
 {
 	struct ldb_context *ldb = NULL;
 	const struct dom_sid *sid = NULL;
-	const char* dn = NULL;
-	struct json_object wrapper;
-	struct json_object audit;
+	const char *dn = NULL;
+	struct json_object wrapper = json_empty_object;
+	struct json_object audit = json_empty_object;
 	const struct tsocket_address *remote = NULL;
 	const char* action = NULL;
 	const struct GUID *unique_session_token = NULL;
 	struct audit_private *audit_private
 		= talloc_get_type_abort(ldb_module_get_private(module),
 					struct audit_private);
-
+	int rc = 0;
 
 	ldb = ldb_module_get_ctx(module);
 
@@ -341,24 +467,79 @@ static struct json_object password_change_json(
 	unique_session_token = dsdb_audit_get_unique_session_token(module);
 
 	audit = json_new_object();
-	json_add_version(&audit, PASSWORD_MAJOR, PASSWORD_MINOR);
-	json_add_int(&audit, "statusCode", reply->error);
-	json_add_string(&audit, "status", ldb_strerror(reply->error));
-	json_add_address(&audit, "remoteAddress", remote);
-	json_add_sid(&audit, "userSid", sid);
-	json_add_string(&audit, "dn", dn);
-	json_add_string(&audit, "action", action);
-	json_add_guid(&audit,
-		      "transactionId",
-		      &audit_private->transaction_guid);
-	json_add_guid(&audit, "sessionId", unique_session_token);
+	if (json_is_invalid(&audit)) {
+		goto failure;
+	}
+	rc = json_add_version(&audit, PASSWORD_MAJOR, PASSWORD_MINOR);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_int(&audit, "statusCode", reply->error);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "status", ldb_strerror(reply->error));
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_address(&audit, "remoteAddress", remote);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_sid(&audit, "userSid", sid);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "dn", dn);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "action", action);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_guid(
+	    &audit, "transactionId", &audit_private->transaction_guid);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_guid(&audit, "sessionId", unique_session_token);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	wrapper = json_new_object();
-	json_add_timestamp(&wrapper);
-	json_add_string(&wrapper, "type", PASSWORD_JSON_TYPE);
-	json_add_object(&wrapper, PASSWORD_JSON_TYPE, &audit);
+	if (json_is_invalid(&wrapper)) {
+		goto failure;
+	}
+	rc = json_add_timestamp(&wrapper);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&wrapper, "type", PASSWORD_JSON_TYPE);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_object(&wrapper, PASSWORD_JSON_TYPE, &audit);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	return wrapper;
+failure:
+	/*
+	 * On a failure audit will not have been added to wrapper so it
+	 * needs to free it to avoid a leak.
+	 *
+	 * wrapper is freed to invalidate it as it will have only been
+	 * partially constructed and may be inconsistent.
+	 *
+	 * All the json manipulation routines handle a freed object correctly
+	 */
+	json_free(&wrapper);
+	json_free(&audit);
+	DBG_ERR("Unable to create password change JSON audit message\n");
+	return wrapper;
 }
 
 
@@ -380,22 +561,64 @@ static struct json_object transaction_json(
 	struct GUID *transaction_id,
 	const int64_t duration)
 {
-	struct json_object wrapper;
-	struct json_object audit;
+	struct json_object wrapper = json_empty_object;
+	struct json_object audit = json_empty_object;
+	int rc = 0;
 
 	audit = json_new_object();
-	json_add_version(&audit, TRANSACTION_MAJOR, TRANSACTION_MINOR);
-	json_add_string(&audit, "action", action);
-	json_add_guid(&audit, "transactionId", transaction_id);
-	json_add_int(&audit, "duration", duration);
+	if (json_is_invalid(&audit)) {
+		goto failure;
+	}
 
+	rc = json_add_version(&audit, TRANSACTION_MAJOR, TRANSACTION_MINOR);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "action", action);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_guid(&audit, "transactionId", transaction_id);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_int(&audit, "duration", duration);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	wrapper = json_new_object();
-	json_add_timestamp(&wrapper);
-	json_add_string(&wrapper, "type", TRANSACTION_JSON_TYPE);
-	json_add_object(&wrapper, TRANSACTION_JSON_TYPE, &audit);
+	if (json_is_invalid(&wrapper)) {
+		goto failure;
+	}
+	rc = json_add_timestamp(&wrapper);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&wrapper, "type", TRANSACTION_JSON_TYPE);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_object(&wrapper, TRANSACTION_JSON_TYPE, &audit);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	return wrapper;
+failure:
+	/*
+	 * On a failure audit will not have been added to wrapper so it
+	 * needs to free it to avoid a leak.
+	 *
+	 * wrapper is freed to invalidate it as it will have only been
+	 * partially constructed and may be inconsistent.
+	 *
+	 * All the json manipulation routines handle a freed object correctly
+	 */
+	json_free(&wrapper);
+	json_free(&audit);
+	DBG_ERR("Unable to create transaction JSON audit message\n");
+	return wrapper;
 }
 
 
@@ -416,24 +639,75 @@ static struct json_object commit_failure_json(
 	const char *reason,
 	struct GUID *transaction_id)
 {
-	struct json_object wrapper;
-	struct json_object audit;
+	struct json_object wrapper = json_empty_object;
+	struct json_object audit = json_empty_object;
+	int rc = 0;
 
 	audit = json_new_object();
-	json_add_version(&audit, TRANSACTION_MAJOR, TRANSACTION_MINOR);
-	json_add_string(&audit, "action", action);
-	json_add_guid(&audit, "transactionId", transaction_id);
-	json_add_int(&audit, "duration", duration);
-	json_add_int(&audit, "statusCode", status);
-	json_add_string(&audit, "status", ldb_strerror(status));
-	json_add_string(&audit, "reason", reason);
+	if (json_is_invalid(&audit)) {
+		goto failure;
+	}
+	rc = json_add_version(&audit, TRANSACTION_MAJOR, TRANSACTION_MINOR);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "action", action);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_guid(&audit, "transactionId", transaction_id);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_int(&audit, "duration", duration);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_int(&audit, "statusCode", status);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "status", ldb_strerror(status));
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "reason", reason);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	wrapper = json_new_object();
-	json_add_timestamp(&wrapper);
-	json_add_string(&wrapper, "type", TRANSACTION_JSON_TYPE);
-	json_add_object(&wrapper, TRANSACTION_JSON_TYPE, &audit);
+	if (json_is_invalid(&wrapper)) {
+		goto failure;
+	}
+	rc = json_add_timestamp(&wrapper);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&wrapper, "type", TRANSACTION_JSON_TYPE);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_object(&wrapper, TRANSACTION_JSON_TYPE, &audit);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	return wrapper;
+failure:
+	/*
+	 * On a failure audit will not have been added to wrapper so it
+	 * needs to free it to avoid a leak.
+	 *
+	 * wrapper is freed to invalidate it as it will have only been
+	 * partially constructed and may be inconsistent.
+	 *
+	 * All the json manipulation routines handle a freed object correctly
+	 */
+	json_free(&audit);
+	json_free(&wrapper);
+	DBG_ERR("Unable to create commit failure JSON audit message\n");
+	return wrapper;
 }
 
 #endif
diff --git a/source4/dsdb/samdb/ldb_modules/audit_util.c b/source4/dsdb/samdb/ldb_modules/audit_util.c
index 766c34c1e23..edf3c5e4b46 100644
--- a/source4/dsdb/samdb/ldb_modules/audit_util.c
+++ b/source4/dsdb/samdb/ldb_modules/audit_util.c
@@ -467,30 +467,39 @@ const char *dsdb_audit_get_modification_action(unsigned int flags)
  * @param lv the ldb_val to convert and append to the array.
  *
  */
-static void dsdb_audit_add_ldb_value(
-	struct json_object *array,
-	const struct ldb_val lv)
+static int dsdb_audit_add_ldb_value(struct json_object *array,
+				    const struct ldb_val lv)
 {
 	bool base64;
 	int len;
-	struct json_object value;
+	struct json_object value = json_empty_object;
+	int rc = 0;
 
 	json_assert_is_array(array);
 	if (json_is_invalid(array)) {
-		return;
+		return -1;
 	}
 
 	if (lv.length == 0 || lv.data == NULL) {
-		json_add_object(array, NULL, NULL);
-		return;
+		rc = json_add_object(array, NULL, NULL);
+		if (rc != 0) {
+			goto failure;
+		}
+		return 0;
 	}
 
 	base64 = ldb_should_b64_encode(NULL, &lv);
 	len = min(lv.length, MAX_LENGTH);
 	value = json_new_object();
+	if (json_is_invalid(&value)) {
+		goto failure;
+	}
 
 	if (lv.length > MAX_LENGTH) {
-		json_add_bool(&value, "truncated", true);
+		rc = json_add_bool(&value, "truncated", true);
+		if (rc != 0) {
+			goto failure;
+		}
 	}
 	if (base64) {
 		TALLOC_CTX *ctx = talloc_new(NULL);
@@ -499,16 +508,43 @@ static void dsdb_audit_add_ldb_value(
 			(char*) lv.data,
 			len);
 
-		json_add_bool(&value, "base64", true);
-		json_add_string(&value, "value", encoded);
+		if (ctx == NULL) {
+			goto failure;
+		}
+
+		rc = json_add_bool(&value, "base64", true);
+		if (rc != 0) {
+			TALLOC_FREE(ctx);
+			goto failure;
+		}
+		rc = json_add_string(&value, "value", encoded);
+		if (rc != 0) {
+			TALLOC_FREE(ctx);
+			goto failure;
+		}
 		TALLOC_FREE(ctx);
 	} else {
-		json_add_stringn(&value, "value", (char *)lv.data, len);
+		rc = json_add_stringn(&value, "value", (char *)lv.data, len);
+		if (rc != 0) {
+			goto failure;
+		}
 	}
 	/*
 	 * As array is a JSON array the element name is NULL
 	 */
-	json_add_object(array, NULL, &value);
+	rc = json_add_object(array, NULL, &value);
+	if (rc != 0) {
+		goto failure;
+	}
+	return 0;
+failure:
+	/*
+	 * In the event of a failure value will not have been added to array
+	 * so it needs to be freed to prevent a leak.
+	 */
+	json_free(&value);
+	DBG_ERR("unable to add ldb value to JSON audit message");
+	return -1;
 }
 
 /*
@@ -550,13 +586,23 @@ struct json_object dsdb_audit_attributes_json(
 	const struct ldb_message* message)
 {
 
-	struct json_object attributes = json_new_object();
 	int i, j;
+	struct json_object attributes = json_new_object();
+
+	if (json_is_invalid(&attributes)) {
+		goto failure;
+	}
 	for (i=0;i<message->num_elements;i++) {
-		struct json_object actions;
-		struct json_object attribute;
-		struct json_object action = json_new_object();
+		struct json_object actions = json_empty_object;
+		struct json_object attribute = json_empty_object;
+		struct json_object action = json_empty_object;
 		const char *name = message->elements[i].name;
+		int rc = 0;
+
+		action = json_new_object();
+		if (json_is_invalid(&action)) {
+			goto failure;
+		}
 
 		/*
 		 * If this is a modify operation tag the attribute with
@@ -566,10 +612,18 @@ struct json_object dsdb_audit_attributes_json(
 			const char *act = NULL;
 			const int flags =  message->elements[i].flags;
 			act = dsdb_audit_get_modification_action(flags);
-			json_add_string(&action, "action" , act);
+			rc = json_add_string(&action, "action", act);
+			if (rc != 0) {
+				json_free(&action);
+				goto failure;
+			}
 		}
 		if (operation == LDB_ADD) {
-			json_add_string(&action, "action" , "add");
+			rc = json_add_string(&action, "action", "add");
+			if (rc != 0) {
+				json_free(&action);
+				goto failure;
+			}
 		}
 
 		/*
@@ -577,25 +631,67 @@ struct json_object dsdb_audit_attributes_json(
 		 * and don't include the values
 		 */
 		if (dsdb_audit_redact_attribute(name)) {
-			json_add_bool(&action, "redacted", true);
+			rc = json_add_bool(&action, "redacted", true);
+			if (rc != 0) {
+				json_free(&action);
+				goto failure;
+			}
 		} else {
 			struct json_object values;
 			/*
 			 * Add the values for the action
 			 */
 			values = json_new_array();
+			if (json_is_invalid(&values)) {
+				json_free(&action);
+				goto failure;
+			}
+
 			for (j=0;j<message->elements[i].num_values;j++) {
-				dsdb_audit_add_ldb_value(
-					&values,
-					message->elements[i].values[j]);
+				rc = dsdb_audit_add_ldb_value(
+				    &values, message->elements[i].values[j]);
+				if (rc != 0) {
+					json_free(&values);
+					json_free(&action);
+					goto failure;
+				}
+			}
+			rc = json_add_object(&action, "values", &values);
+			if (rc != 0) {
+				json_free(&values);
+				json_free(&action);
+				goto failure;
 			}
-			json_add_object(&action, "values", &values);
 		}
 		attribute = json_get_object(&attributes, name);
+		if (json_is_invalid(&attribute)) {
+			json_free(&action);
+			goto failure;
+		}
 		actions = json_get_array(&attribute, "actions");
-		json_add_object(&actions, NULL, &action);
-		json_add_object(&attribute, "actions", &actions);
-		json_add_object(&attributes, name, &attribute);
+		if (json_is_invalid(&actions)) {
+			json_free(&action);
+			goto failure;
+		}
+		rc = json_add_object(&actions, NULL, &action);
+		if (rc != 0) {
+			json_free(&action);
+			goto failure;
+		}
+		rc = json_add_object(&attribute, "actions", &actions);
+		if (rc != 0) {
+			json_free(&actions);
+			goto failure;
+		}
+		rc = json_add_object(&attributes, name, &attribute);
+		if (rc != 0) {
+			json_free(&attribute);
+			goto failure;
+		}
 	}
 	return attributes;
+failure:
+	json_free(&attributes);
+	DBG_ERR("Unable to create ldb attributes JSON audit message\n");
+	return attributes;
 }
diff --git a/source4/dsdb/samdb/ldb_modules/group_audit.c b/source4/dsdb/samdb/ldb_modules/group_audit.c
index eb592adc336..d5c9bbdaa1e 100644
--- a/source4/dsdb/samdb/ldb_modules/group_audit.c
+++ b/source4/dsdb/samdb/ldb_modules/group_audit.c
@@ -104,6 +104,7 @@ static struct GUID *get_transaction_id(
  * @param status the ldb status code for the ldb operation.
  *
  * @return A json object containing the details.
+ * 	   NULL if an error was detected
  */
 static struct json_object audit_group_json(
 	const struct ldb_module *module,
@@ -115,11 +116,12 @@ static struct json_object audit_group_json(
 {
 	struct ldb_context *ldb = NULL;
 	const struct dom_sid *sid = NULL;
-	struct json_object wrapper;
-	struct json_object audit;
+	struct json_object wrapper = json_empty_object;
+	struct json_object audit = json_empty_object;
 	const struct tsocket_address *remote = NULL;
 	const struct GUID *unique_session_token = NULL;
 	struct GUID *transaction_id = NULL;
+	int rc = 0;
 
 	ldb = ldb_module_get_ctx(discard_const(module));
 
@@ -129,23 +131,82 @@ static struct json_object audit_group_json(
 	transaction_id = get_transaction_id(request);
 
 	audit = json_new_object();
-	json_add_version(&audit, AUDIT_MAJOR, AUDIT_MINOR);
-	json_add_int(&audit, "statusCode", status);
-	json_add_string(&audit, "status", ldb_strerror(status));
-	json_add_string(&audit, "action", action);
-	json_add_address(&audit, "remoteAddress", remote);
-	json_add_sid(&audit, "userSid", sid);
-	json_add_string(&audit, "group", group);
-	json_add_guid(&audit, "transactionId", transaction_id);
-	json_add_guid(&audit, "sessionId", unique_session_token);
-	json_add_string(&audit, "user", user);
+	if (json_is_invalid(&audit)) {
+		goto failure;
+	}
+	rc = json_add_version(&audit, AUDIT_MAJOR, AUDIT_MINOR);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_int(&audit, "statusCode", status);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "status", ldb_strerror(status));
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "action", action);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_address(&audit, "remoteAddress", remote);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_sid(&audit, "userSid", sid);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "group", group);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_guid(&audit, "transactionId", transaction_id);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_guid(&audit, "sessionId", unique_session_token);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&audit, "user", user);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	wrapper = json_new_object();
-	json_add_timestamp(&wrapper);
-	json_add_string(&wrapper, "type", AUDIT_JSON_TYPE);
-	json_add_object(&wrapper, AUDIT_JSON_TYPE, &audit);
+	if (json_is_invalid(&wrapper)) {
+		goto failure;
+	}
+	rc = json_add_timestamp(&wrapper);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_string(&wrapper, "type", AUDIT_JSON_TYPE);
+	if (rc != 0) {
+		goto failure;
+	}
+	rc = json_add_object(&wrapper, AUDIT_JSON_TYPE, &audit);
+	if (rc != 0) {
+		goto failure;
+	}
 
 	return wrapper;
+failure:
+	/*
+	 * On a failure audit will not have been added to wrapper so it
+	 * needs to free it to avoid a leak.
+	 *
+	 * wrapper is freed to invalidate it as it will have only been
+	 * partially constructed and may be inconsistent.
+	 *
+	 * All the json manipulation routines handle a freed object correctly
+	 */
+	json_free(&audit);
+	json_free(&wrapper);
+	DBG_ERR("Failed to create group change JSON log message\n");
+	return wrapper;
 }
 #endif
 
diff --git a/source4/dsdb/samdb/ldb_modules/tests/test_group_audit.c b/source4/dsdb/samdb/ldb_modules/tests/test_group_audit.c
index 75e14fed2e2..de3785463ec 100644
--- a/source4/dsdb/samdb/ldb_modules/tests/test_group_audit.c
+++ b/source4/dsdb/samdb/ldb_modules/tests/test_group_audit.c
@@ -94,7 +94,7 @@ void audit_message_send(
 	struct json_object *message)
 {
 	messages[messages_sent].root = json_deep_copy(message->root);
-	messages[messages_sent].error = message->error;
+	messages[messages_sent].valid = message->valid;
 	messages_sent++;
 }