how to update userprofile password in laravel5

when i am update my password in my profile page the password should be changed almost its working fine.but i am not entered any password in the field on that time i click submit button automatically password should generated in db.suggest me something

my html:

      <form class="form-horizontal" role="form" id="loginForm" method="POST" action="{{ url('updatepassword') }}">
                                                 <input type="hidden" name="_token" value="{{ csrf_token() }}">
                                        <div class="post-content col-sm-12">
                                            <h3 class="post-title">Change Password</h3>
                                            <div class="form-group col-xs-5">
                                                <label>Password</label>
                                                 <input type="password"  class="form-control" name="password">
                                            </div>
                                            <div class="form-group col-xs-5 mm">
                                                <label>Confirm Password</label>
                                                 <input type="password"   class="form-control" name="password_confirmation">
                                            </div>  
                                            <div class="form-group col-xs-2">
                                                <label>&nbsp;</label>
                                                <button id="login" type="submit" class="btn btn-info btn-block btn-flat ">Update</button>
                                            </div>
                                        </div>
                          </form>

controller:

  public function updatepassword(Request $request)
{

    $user =new User;
    $user->where('email', '=' ,Auth::user()->email)
     ->update([ 'password' => Hash::make('secret')]);
       return Redirect::to('user_profile');
     }

router:

Route::post('updatepassword',array('as' =>'password','uses' => 'UserController@updatepassword'));

via Chebli Mohamed