loki/docs/sources/clients/aws/ecs/ecs-role.json

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Principal": {
                "Service": [
                    "ecs-tasks.amazonaws.com"
                ]
            },
            "Action": "sts:AssumeRole"
        }
    ]
}