Bug#7242

The "insert_update" causes a server crash when using prepared statements

Must clear table->insert_values after completing every prepared statement

sql/sql_prepare.cc

@@ -1514,6 +1514,27 @@ static bool init_param_array(Prepared_statement *stmt)
 }
 
 
+/* Init statement before execution */
+
+static void cleanup_stmt_for_execute(Prepared_statement *stmt)
+{
+  THD *thd= stmt->thd;
+  LEX *lex= stmt->lex;
+  SELECT_LEX *sl= lex->all_selects_list;
+
+  for (; sl; sl= sl->next_select_in_list())
+  {
+    for (TABLE_LIST *tables= (TABLE_LIST*) sl->table_list.first;
+	 tables;
+	 tables= tables->next)
+    {
+      if (tables->table)
+        tables->table->insert_values= 0;
+    }
+  }
+}
+
+
 /*
   Given a query string with parameter markers, create a Prepared Statement
   from it and send PS info back to the client.
@@ -1614,6 +1635,7 @@ int mysql_stmt_prepare(THD *thd, char *packet, uint packet_length,
 
   if (!error)
     error= send_prepare_results(stmt, test(name));
+  cleanup_stmt_for_execute(stmt);
 
   /* restore to WAIT_PRIOR: QUERY_PRIOR is set inside alloc_query */
   if (!(specialflag & SPECIAL_NO_PRIOR))
@@ -1904,6 +1926,7 @@ static void execute_stmt(THD *thd, Prepared_statement *stmt,
   reset_stmt_params(stmt);
   close_thread_tables(thd);                    // to close derived tables
   thd->set_statement(&thd->stmt_backup);
+  cleanup_stmt_for_execute(stmt);
   DBUG_VOID_RETURN;
 }