Necessary s3cmd S3 permissions for PUT/Sync

Question

In moving to AWS EC2, I want to restrict my instances\' user permissions for good reason. One thing the instances need to do is access files on S3 and write files there. However

Answer 1

bwight's answer is almost right (it probably used to be for older versions of s3cmd), but I need to add a s3:PutObjectAcl to get it to work:

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Sid": "Stmt123456",
      "Effect": "Allow",
      "Action": [
        "s3:ListAllMyBuckets"
      ],
      "Resource": [
        "arn:aws:s3:::*"
      ]
    },
    {
      "Sid": "Stmt123457",
      "Effect": "Allow",
      "Action": [
        "s3:ListBucket",
        "s3:PutObject",
        "s3:PutObjectAcl"
      ],
      "Resource": [
        "arn:aws:s3:::bucketname",
        "arn:aws:s3:::bucketname/*"
      ]
    }
  ]
}