Fix signature validation

models/LoginForm.php

@@ -34,14 +34,17 @@ class LoginForm extends Model
     /**
      * Validates the password.
      * This method serves as the inline validation for password.
+     *
+     * @param string $attribute the attribute currently being validated
+     * @param array $params the additional name-value pairs given in the rule
      */
-    public function validatePassword()
+    public function validatePassword($attribute, $params)
     {
         if (!$this->hasErrors()) {
             $user = $this->getUser();
 
             if (!$user || !$user->validatePassword($this->password)) {
-                $this->addError('password', 'Incorrect username or password.');
+                $this->addError($attribute, 'Incorrect username or password.');
             }
         }
     }