diff --git a/src/inc_internal/Maat_rule_internal.h b/src/inc_internal/Maat_rule_internal.h
index 4a0d04c..8638f0b 100644
--- a/src/inc_internal/Maat_rule_internal.h
+++ b/src/inc_internal/Maat_rule_internal.h
@@ -40,8 +40,8 @@ struct db_str_rule_t
 {
 	int region_id;
 	int group_id;
-	char keywords[MAX_EXPR_KEYLEN];
-	char district[MAX_DISTRICT_LEN];
+	char keywords[MAX_EXPR_KEYLEN+1];
+	char district[MAX_DISTRICT_LEN+1];
 	enum MAAT_EXPR_TYPE expr_type;
 	enum MAAT_MATCH_METHOD match_method;
 	int is_hexbin;