This is an odd one.

I can use the conftest command to push a policy bundle to my public quay.io repository.

If I try to push the bundle again (same digest) to a different tag on the same repository, the following error is seen:

Error: push bundle: pushing manifest: failed to read expected number of bytes: unexpected EOF

(The error bubbles up from the underlying golang library "oras.land/oras-go/pkg/oras")

Important notes:

• I cannot reproduce the issue when using skopeo copy --all.
• I cannot reproduce the issue on Docker Hub.
• I cannot reproduce the issue on private repos in quay.io. However, as soon as I make the repository public, the issue is seen.

Reproducer:

First, install conftest (https://github.com/open-policy-agent/conftest/releases/tag/v0.38.0)

mkdir /tmp/policy
echo 'package main' > /tmp/policy/main.rego
conftest push -p /tmp/policy quay.io/<org>/<public-repo>:one
conftest push -p /tmp/policy quay.io/<org>/<public-repo>:two

The second conftest command should fail with the previously mentioned error.