You can do that by a drush script looking like this:
$users = entity_load('user');
foreach ($users as $user) {
$node = new stdClass();
$node->type = 'yourContentType';
$node->status = 1;
$node->uid = $user->uid;
$node->title = $user->name;
$node->promote = 0;
$node->sticky = 0;
$node->language = 'en';
$node->body = '<p>body</p>';
node_save($node);
}
Here is more info about how to execute it How to execute php script using drush?How to execute php script using drush?