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');

    }

My form Role create

@extends('admin.layout.admin')
@section('content')
    <h3>Create Roles</h3>

    <form action="" method="post" role="form">
        

        <div class="form-group">
            <label for="name">Name of role</label>
            <input type="text" class="form-control" name="name" id="" placeholder="Name of role">
        </div>
        <div class="form-group">
            <label for="display_name">Display name</label>
            <input type="text" class="form-control" name="display_name" id="" placeholder="Display name">
        </div>
        <div class="form-group">
            <label for="description">Description</label>
            <input type="text" class="form-control" name="description" id="" placeholder="Description">
        </div>

        
            
            
        

        <div class="form-group text-left">
            <h3>Permissions</h3>
            @foreach($permissions as $permission)
            <input type="checkbox"   name="permission[]" value="" >  <br>
            @endforeach
        </div>






        <button type="submit" class="btn btn-primary">Submit</button>
    </form>

@endsection

My form - Role index

@extends('admin.layout.admin')
@section('content')
    <h3>Roles</h3>
    <a class="btn btn-success" href=""> Create Role</a>
    <table class="table">
        <tr>
            <th>Name</th>
            <th>Display Name</th>
            <th>Description</th>
            <th>Action</th>
        </tr>

        @forelse($roles as $role)
            <tr>
                <td></td>
                <td></td>
                <td></td>
                <td>
                    <a class="btn btn-info btn-sm" href="">Edit</a>
                    <form action=""  method="POST">
                       
                       
                       <input class="btn btn-sm btn-danger" type="submit" value="Delete">
                     </form>
                </td>
            </tr>
            @empty
            <tr>
                <td>No roles</td>
            </tr>
            @endforelse

    </table>


@endsection

Thank you for your help.

via Chebli Mohamed