ErrorException in RoleController.php line 44: Invalid argument supplied for foreach()

I am stuck about a problem, in fact I want to create a Role and a Permission. In my form.

I added the informations for each fields.

I have an error message:

ErrorException in RoleController.php line 44: Invalid argument supplied for foreach()

Here is a party of my code, I don't see the error??

public function store(Request $request)
    {
        $role=Role::create($request->except(['permission','_token']));

        foreach ($request->permission as $key=>$value){
            $role->attachPermission($value);
        }

        return redirect()->route('role.index')->withMessage('role created');

    }

Thank you for your help.

via Chebli Mohamed