non-root opm fails when a layer contains a file owned by root

[mprahl]

The following command fails when running as a non-root user:
opm index add --generate --bundles registry-proxy-stage.engineering.redhat.com:443/rh-osbs-stage/e2e-e2e-test-rhel8-operator@sha256:6a525f684641298088ced4a7df91a7937d00a433cc5ddf404d6409bc5e2d9b89 --binary-image registry-proxy.engineering.redhat.com/rh-osbs/openshift-ose-operator-registry@sha256:ed2481437d9713fc49d76d101ee0b5bd5f6b53a3e8b440ae3551563aea4ff2bf --from-index registry-proxy-stage.engineering.redhat.com/rh-osbs-stage/iib:985.

This fails with:

INFO[0029] unpacking layer: {application/vnd.docker.image.rootfs.diff.tar.gzip sha256:5b8ca0a26d14dc05be7ace7233b529d56c3f42f0e994b01293ffe6b310df375f 80467927 [] map[] <nil>}  bundles="[registry-proxy-stage.engineering.redhat.com:443/rh-osbs-stage/e2e-e2e-test-rhel8-operator@sha256:6a525f684641298088ced4a7df91a7937d00a433cc5ddf404d6409bc5e2d9b89]"
Error: open index_tmp_731416721/root/.bash_logout: permission denied

If I run the same command as root, it is successful. Additionally, if I run the same command using podman v1.9.2 as shown here, it works just fine:

opm index add --generate --bundles registry-proxy-stage.engineering.redhat.com:443/rh-osbs-stage/e2e-e2e-test-rhel8-operator@sha256:6a525f684641298088ced4a7df91a7937d00a433cc5ddf404d6409bc5e2d9b89 --binary-image registry-proxy.engineering.redhat.com/rh-osbs/openshift-ose-operator-registry@sha256:ed2481437d9713fc49d76d101ee0b5bd5f6b53a3e8b440ae3551563aea4ff2bf --from-index registry-proxy-stage.engineering.redhat.com/rh-osbs-stage/iib:985 --container-tool podman

Using podman would be a suitable workaround if podman v1.9.2 was released for RHEL 8, but the latest is 1.6.4 and that version does not have the following feature which is required containers/podman#5234 for using digests instead of tags.

By the way, here is the output of opm version:

Version: version.Version{OpmVersion:"", GitCommit:"", BuildDate:"2020-05-13T21:01:13Z", GoOs:"linux", GoArch:"amd64"}

[mprahl]

FYI, I filed a corresponding Bugzilla Bug:
https://bugzilla.redhat.com/show_bug.cgi?id=1840727