`ostree pull-local` failing to `openat(<checksum>.filez)` with EINVAL

[jlebon]

+ ostree pull-local --repo /tmp/rootfs/ostree/repo /home/jenkins/agent/workspace/rhcos/rhcos-rhcos-4.10/tmp/repo 371919701a4139c2df6685738f91c4ac7f23d4c586b9e6ef2014069942408d90
error: openat(f7/ee6a9b728a11e0c62bd4b8a20c741d76cf637277434e0716fa1ea82f0e80fe.filez): Invalid argument

This is happening in the RHCOS pipeline, as part of coreos-assembler, when running create_disk.sh inside a supermin VM. Only seems to have happened on ppc64le and s390x so far. It seems to corresponds with v2021.4 entering cosa so we possibly have a regression there. But it's possibly some other package that changed too.

[jlebon]

I had an initial look at the v2021.3..v2021.4 diff and didn't see anything obvious there. But other eyes welcome.

Will try to get a run with just ostree reverted to v2021.3 as a test.

[cgwalters]

It'd be useful to prefix with strace -f -s 2048 -e openat.

Seems more likely to me to be related to something like a glibc update. A weird thing with open() and openat() is the variadic nature, i.e mode can be omitted when doing open(..., O_RDONLY) - maybe related to us not passing a mode with O_RDONLY in some case?