Bug#21246964: ASAN: MEMORY LEAK IN PROCESS_ALL_TABLES()

Bug#21247377: ASAN: MEMORY LEAK IN SHOW_VARIABLE_QUERY_EXTRACTOR / RUN_SQL_FIX_PRIVILEGE_TABLES()
Bug#21253535: ASAN: MEMORY LEAK IN MYSQL_UPGRADE

Fix memory leak in mysqlcheck - process_all_tables().
Close result by calling mysql_free_result() after processing.

Fix memory leaks related to mysql_upgrade:
1) Allocate Instance_callback instances on stack rather than heap.
2) Always call mysql_close() to deallocate memory.

Also fix a valgrind warning,
Conditional jump or move depends on uninitialised value(s)
in Mysql::Tools::Upgrade::Program::fix_privilage_tables_error()
(sic)

Author: jhauglid

client/check/mysqlcheck_core.cc

@@ -81,6 +81,7 @@ static int process_all_databases()
     if (process_one_db(row[0]))
       result = 1;
   }
+  mysql_free_result(tableres);
   return result;
 }
 /* process_all_databases */

client/upgrade/program.cc

@@ -78,6 +78,23 @@ enum exit_codes
   EXIT_UPGRADING_QUERIES_ERROR = 5,
 };
 
+
+class Mysql_connection_holder
+{
+  MYSQL* m_mysql_connection;
+
+public:
+  explicit Mysql_connection_holder(MYSQL *mysql_connection)
+    : m_mysql_connection(mysql_connection)
+  { }
+
+  ~Mysql_connection_holder()
+  {
+    mysql_close(this->m_mysql_connection);
+  }
+};
+
+
 class Program : public Base::Abstract_connection_program
 {
 public:
@@ -119,6 +136,8 @@ class Program : public Base::Abstract_connection_program
     setbuf(stdout, NULL);
 
     this->m_mysql_connection= this->create_connection();
+    // Remember to call mysql_close()
+    Mysql_connection_holder connection_holder(m_mysql_connection);
     this->m_query_runner= new Mysql_query_runner(this->m_mysql_connection);
     this->m_query_runner->add_message_callback(new Instance_callback
       <int, Mysql_message, Program>(this, &Program::print_error));
@@ -434,8 +453,6 @@ class Program : public Base::Abstract_connection_program
     /* Create a file indicating upgrade has been performed */
     this->create_mysql_upgrade_info_file();
 
-    mysql_close(this->m_mysql_connection);
-
     return 0;
   }
 
@@ -525,13 +542,13 @@ class Program : public Base::Abstract_connection_program
     const char **query_ptr;
     int result;
 
+    Instance_callback<int, vector<string>, Program>
+      result_callback(this, &Program::result_callback);
+    Instance_callback<int, Mysql_message, Program>
+      message_callback(this, &Program::fix_privilage_tables_error);
     Mysql_query_runner runner(*this->m_query_runner);
-    runner.add_result_callback(
-      new Instance_callback<int, vector<string>, Program>(
-      this, &Program::result_callback));
-    runner.add_message_callback(
-      new Instance_callback<int, Mysql_message, Program>(
-      this, &Program::fix_privilage_tables_error));
+    runner.add_result_callback(&result_callback);
+    runner.add_message_callback(&message_callback);
 
     this->print_verbose_message("Running queries to upgrade MySQL server.");
 
@@ -565,13 +582,13 @@ class Program : public Base::Abstract_connection_program
     const char **query_ptr;
     int result;
 
+    Instance_callback<int, vector<string>, Program>
+      result_callback(this, &Program::result_callback);
+    Instance_callback<int, Mysql_message, Program>
+      message_callback(this, &Program::fix_privilage_tables_error);
     Mysql_query_runner runner(*this->m_query_runner);
-    runner.add_result_callback(
-      new Instance_callback<int, vector<string>, Program>(
-      this, &Program::result_callback));
-    runner.add_message_callback(
-      new Instance_callback<int, Mysql_message, Program>(
-      this, &Program::fix_privilage_tables_error));
+    runner.add_result_callback(&result_callback);
+    runner.add_message_callback(&message_callback);
 
     this->print_verbose_message("Upgrading the sys schema.");
 
@@ -744,13 +761,8 @@ class Program : public Base::Abstract_connection_program
    */
   int fix_privilage_tables_error(Mysql_message message)
   {
-    String error;
-    uint dummy_errors;
-    error.copy("error", 5, &my_charset_latin1,
-      this->m_mysql_connection->charset, &dummy_errors);
-
     bool is_error = my_strcasecmp(this->m_mysql_connection->charset,
-      message.severity.c_str(), error.c_ptr()) == 0;
+                                  message.severity.c_str(), "error") == 0;
 
     // This if it is error message and if it is not expected one.
     if (this->m_temporary_verbose ||

client/upgrade/show_variable_query_extractor.cc

@@ -36,9 +36,9 @@ int Show_variable_query_extractor::get_variable_value(
   Show_variable_query_extractor extractor;
   Mysql_query_runner query_runner_to_use(*query_runner_to_copy);
 
-  query_runner_to_use.add_result_callback(
-    new Instance_callback<int, vector<string>, Show_variable_query_extractor>(
-      &extractor, &Show_variable_query_extractor::extract_variable));
+  Instance_callback<int, vector<string>, Show_variable_query_extractor>
+    callback(&extractor, &Show_variable_query_extractor::extract_variable);
+  query_runner_to_use.add_result_callback(&callback);
 
   if (query_runner_to_use.run_query("SELECT @@global." + variable))
     return 1;