diff --git a/sources/config_reader.c b/sources/config_reader.c
index 96d3a66c..ca85fa56 100644
--- a/sources/config_reader.c
+++ b/sources/config_reader.c
@@ -767,13 +767,18 @@ od_config_reader_route(od_config_reader_t *reader,
 			/* quantiles */
 			case OD_LQUANTILES: {
 				char *quantiles_str = NULL;
-				if (!od_config_reader_string(reader, &quantiles_str))
-					return -1;
+				if (!od_config_reader_string(reader, &quantiles_str)) {
+					free(quantiles_str);
+					return NOT_OK_RESPONSE;
+				}
 				if (!od_config_reader_quantiles(reader,
 				                                quantiles_str,
 				                                &route->quantiles,
-				                                &route->quantiles_count))
-					return -1;
+				                                &route->quantiles_count)) {
+					free(quantiles_str);
+					return NOT_OK_RESPONSE;
+				}
+				free(quantiles_str);
 			} break;
 			/* application_name_add_host */
 			case OD_LAPPLICATION_NAME_ADD_HOST:
diff --git a/sources/counter.c b/sources/counter.c
index 975e37e3..4557a0d6 100644
--- a/sources/counter.c
+++ b/sources/counter.c
@@ -4,25 +4,29 @@
 inline od_counter_llist_t *
 od_counter_llist_create(void)
 {
-	od_counter_llist_t *l = malloc(sizeof(od_counter_llist_t));
+	od_counter_llist_t *llist = malloc(sizeof(od_counter_llist_t));
+	if (llist == NULL)
+		return NULL;
 
-	l->list  = NULL;
-	l->count = 0;
+	llist->list  = NULL;
+	llist->count = 0;
 
-	return l;
+	return llist;
 }
 
 inline void
-od_counter_llist_add(od_counter_llist_t *l, const od_counter_item_t *it)
+od_counter_llist_add(od_counter_llist_t *llist, const od_counter_item_t *it)
 {
 	od_counter_litem_t *litem = malloc(sizeof(od_counter_litem_t));
-	litem->value              = *it;
-	litem->cnt                = 1;
+	if (litem == NULL)
+		return;
+	litem->value = *it;
+	litem->cnt   = 1;
 
-	litem->next = l->list;
-	l->list     = litem;
+	litem->next = llist->list;
+	llist->list = litem;
 
-	++l->count;
+	++llist->count;
 }
 
 inline od_retcode_t
@@ -42,13 +46,27 @@ od_counter_t *
 od_counter_create(size_t sz)
 {
 	od_counter_t *t = malloc(sizeof(od_counter_t));
-	t->buckets      = malloc(sizeof(od_counter_llist_t) * sz);
+	if (t == NULL) {
+		return NULL;
+	}
+	t->buckets = malloc(sizeof(od_counter_llist_t) * sz);
+	if (t->buckets == NULL) {
+		return NULL;
+	}
 	t->bucket_mutex = malloc(sizeof(pthread_mutex_t) * sz);
-	t->size         = sz;
+	if (t->bucket_mutex == NULL) {
+		return NULL;
+	}
+	t->size = sz;
 
 	for (size_t i = 0; i < t->size; ++i) {
 		t->buckets[i] = od_counter_llist_create();
-		pthread_mutex_init(&t->bucket_mutex[i], NULL);
+		if (t->buckets[i] == NULL)
+			return NULL;
+		const int res = pthread_mutex_init(&t->bucket_mutex[i], NULL);
+		if (res) {
+			return NULL;
+		}
 	}
 
 	return t;
diff --git a/sources/counter.h b/sources/counter.h
index c5398873..36a39234 100644
--- a/sources/counter.h
+++ b/sources/counter.h
@@ -8,7 +8,6 @@
  * Scalable PostgreSQL connection pooler.
  */
 
-#include <malloc.h>
 #include <kiwi.h>
 #include "macro.h"
 
@@ -40,7 +39,7 @@ extern od_counter_llist_t *
 od_counter_llist_create(void);
 
 extern void
-od_counter_llist_add(od_counter_llist_t *l, const od_counter_item_t *it);
+od_counter_llist_add(od_counter_llist_t *llist, const od_counter_item_t *it);
 
 extern od_retcode_t
 od_counter_llist_free(od_counter_llist_t *l);
diff --git a/sources/err_logger.c b/sources/err_logger.c
index afae62fb..8c8308dd 100644
--- a/sources/err_logger.c
+++ b/sources/err_logger.c
@@ -4,33 +4,39 @@
 od_error_logger_t *
 od_err_logger_create(size_t intervals_count)
 {
-	od_error_logger_t *l = malloc(sizeof(od_error_logger_t));
-
-	l->intercals_cnt        = intervals_count;
-	l->current_interval_num = 0;
-
-	l->interval_counters = malloc(sizeof(od_counter_t) * intervals_count);
-
-	for (size_t i = 0; i < intervals_count; ++i) {
-		l->interval_counters[i] = od_counter_create_default();
+	od_error_logger_t *err_logger = malloc(sizeof(od_error_logger_t));
+	if (err_logger == NULL) {
+		return NULL;
 	}
 
-	pthread_mutex_init(&l->lock, NULL);
+	err_logger->intercals_cnt        = intervals_count;
+	err_logger->current_interval_num = 0;
 
-	return l;
+	err_logger->interval_counters =
+	  malloc(sizeof(od_counter_t) * intervals_count);
+
+	for (size_t i = 0; i < intervals_count; ++i) {
+		err_logger->interval_counters[i] = od_counter_create_default();
+		if (err_logger->interval_counters[i] == NULL)
+			return NULL;
+	}
+
+	pthread_mutex_init(&err_logger->lock, NULL);
+
+	return err_logger;
 }
 
 od_retcode_t
-od_err_logger_free(od_error_logger_t *l)
+od_err_logger_free(od_error_logger_t *err_logger)
 {
-	for (size_t i = 0; i < l->intercals_cnt; ++i) {
-		int rc = od_counter_free(l->interval_counters[i]);
+	for (size_t i = 0; i < err_logger->intercals_cnt; ++i) {
+		int rc = od_counter_free(err_logger->interval_counters[i]);
 		if (rc != OK_RESPONSE)
 			return rc;
 	}
 
-	pthread_mutex_destroy(&l->lock);
-	free(l);
+	pthread_mutex_destroy(&err_logger->lock);
+	free(err_logger);
 
 	return OK_RESPONSE;
 }
diff --git a/sources/err_logger.h b/sources/err_logger.h
index 17e0c826..6e39f34d 100644
--- a/sources/err_logger.h
+++ b/sources/err_logger.h
@@ -37,7 +37,7 @@ od_err_logger_create_default()
 }
 
 extern od_retcode_t
-od_err_logger_free(od_error_logger_t *l);
+od_err_logger_free(od_error_logger_t *err_logger);
 
 static inline od_retcode_t
 od_err_logger_inc_interval(od_error_logger_t *l)
diff --git a/sources/frontend.c b/sources/frontend.c
index 5a050342..1f9e7ed4 100644
--- a/sources/frontend.c
+++ b/sources/frontend.c
@@ -785,9 +785,9 @@ od_frontend_remote(od_client_t *client)
 		status = od_relay_step(&server->relay);
 		if (status == OD_DETACH) {
 			/* write any pending data to server first */
-			od_frontend_status_t status;
-			status = od_relay_flush(&server->relay);
-			if (status != OD_OK)
+			od_frontend_status_t flush_status;
+			flush_status = od_relay_flush(&server->relay);
+			if (flush_status != OD_OK)
 				break;
 			od_relay_detach(&client->relay);
 			od_relay_stop(&server->relay);
@@ -795,7 +795,7 @@ od_frontend_remote(od_client_t *client)
 			/* cleanup server */
 			rc = od_reset(server);
 			if (rc == -1) {
-				status = OD_ESERVER_WRITE;
+				flush_status = OD_ESERVER_WRITE;
 				break;
 			}
 
@@ -810,11 +810,11 @@ od_frontend_remote(od_client_t *client)
 	}
 
 	if (client->server) {
-		od_server_t *server = client->server;
+		od_server_t *curr_server = client->server;
 
 		od_frontend_status_t flush_status;
-		flush_status = od_relay_flush(&server->relay);
-		od_relay_stop(&server->relay);
+		flush_status = od_relay_flush(&curr_server->relay);
+		od_relay_stop(&curr_server->relay);
 		if (flush_status != OD_OK) {
 			return flush_status;
 		}
diff --git a/sources/instance.c b/sources/instance.c
index 2541baad..590075db 100644
--- a/sources/instance.c
+++ b/sources/instance.c
@@ -90,10 +90,11 @@ od_instance_main(od_instance_t *instance, int argc, char **argv)
 	/* validate command line options */
 	if (argc != 2) {
 		od_usage(instance, argv[0]);
-		return -1;
+		goto error;
 	}
 	if (strcmp(argv[1], "-h") == 0 || strcmp(argv[1], "--help") == 0) {
 		od_usage(instance, argv[0]);
+		od_router_free(&router);
 		return 0;
 	}
 	instance->config_file = argv[1];
@@ -109,18 +110,20 @@ od_instance_main(od_instance_t *instance, int argc, char **argv)
 	                             instance->config_file);
 	if (rc == -1) {
 		od_error(&instance->logger, "config", NULL, NULL, "%s", error.error);
-		return -1;
+		goto error;
 	}
 
 	/* validate configuration */
 	rc = od_config_validate(&instance->config, &instance->logger);
-	if (rc == -1)
-		return -1;
+	if (rc == -1) {
+		goto error;
+	}
 
 	/* validate rules */
 	rc = od_rules_validate(&router.rules, &instance->config, &instance->logger);
-	if (rc == -1)
-		return -1;
+	if (rc == -1) {
+		goto error;
+	}
 
 	/* configure logger */
 	od_logger_set_format(&instance->logger, instance->config.log_format);
@@ -130,8 +133,9 @@ od_instance_main(od_instance_t *instance, int argc, char **argv)
 	/* run as daemon */
 	if (instance->config.daemonize) {
 		rc = od_daemonize();
-		if (rc == -1)
-			return -1;
+		if (rc == -1) {
+			goto error;
+		}
 		/* update pid */
 		od_pid_init(&instance->pid);
 	}
@@ -146,7 +150,7 @@ od_instance_main(od_instance_t *instance, int argc, char **argv)
 			         NULL,
 			         "failed to open log file '%s'",
 			         instance->config.log_file);
-			return -1;
+			goto error;
 		}
 	}
 
@@ -202,7 +206,7 @@ od_instance_main(od_instance_t *instance, int argc, char **argv)
 	if (rc == -1) {
 		od_error(
 		  &instance->logger, "init", NULL, NULL, "failed to init machinarium");
-		return -1;
+		goto error;
 	}
 
 	/* create pid file */
@@ -211,8 +215,13 @@ od_instance_main(od_instance_t *instance, int argc, char **argv)
 
 	/* start system machine thread */
 	rc = od_system_start(&system, &global);
-	if (rc == -1)
-		return -1;
+	if (rc == -1) {
+		goto error;
+	}
 
 	return machine_wait(system.machine);
+
+error:
+	od_router_free(&router);
+	return NOT_OK_RESPONSE;
 }
diff --git a/sources/route.h b/sources/route.h
index e8fa6c4a..5645e3fd 100644
--- a/sources/route.h
+++ b/sources/route.h
@@ -42,7 +42,7 @@ od_route_init(od_route_t *route)
 	/* stat init */
 	route->stats_mark_db = false;
 
-	/* error logging*/;
+	/* error logging */;
 	route->frontend_err_logger = od_err_logger_create_default();
 
 	od_stat_init(&route->stats);
diff --git a/sources/router.c b/sources/router.c
index dcce6053..a8015c78 100644
--- a/sources/router.c
+++ b/sources/router.c
@@ -39,6 +39,7 @@ od_router_free(od_router_t *router)
 	od_route_pool_free(&router->route_pool);
 	od_rules_free(&router->rules);
 	pthread_mutex_destroy(&router->lock);
+	od_err_logger_free(router->router_err_logger);
 }
 
 inline int