Os is empty string

[vertti]

/kind bug

Description

Originally filed it to buildah here containers/buildah#2225 but it seems not to be a buildah issue.

Steps to reproduce the issue:

podman build produces images that when inspected show Os field as empty "" instead of expected linux.

OpenShift refuses to run these containers and prints out:

Image operating system mismatch: image uses "", expecting "linux"

Steps to reproduce the issue:

1. Use Dockerfile like:

FROM node:12-buster

ADD package.json .

2. run podman build -t website .
3. run podman inspect website

Describe the results you received:

Check Os field in the output. It's "" instead of "linux"

Describe the results you expected:

Check Os field in the output. It's "" instead of "linux"
Running for example podman inspect node:12-buster will show "Os": "linux",

Additional information you deem important (e.g. issue happens only occasionally):

While discussing on the buildah issue tracker, it seems buildah will get the correct Os field:

I also get the correct "linux" result with your buildah command. But podman still prints empty string for Os.

$ cat Dockerfile 
FROM node:12-buster

ADD package.json .

$ sudo buildah bud -t tom -f Dockerfile --layers .
STEP 1: FROM node:12-buster
STEP 2: ADD package.json .
--> Using cache c07c461de47b57ef1588a2456c70144ef465b90f19559f5c53e8b798fcf0a195
STEP 3: COMMIT tom
--> c07c461de47
c07c461de47b57ef1588a2456c70144ef465b90f19559f5c53e8b798fcf0a195

$ sudo buildah inspect --format '{{.Docker.OS}}' tom
linux

but continuing with podman you can see the layer hashes match:

$ sudo podman build -t foo .
STEP 1: FROM node:12-buster
STEP 2: ADD package.json .
--> Using cache c07c461de47b57ef1588a2456c70144ef465b90f19559f5c53e8b798fcf0a195
STEP 3: COMMIT foo
--> c07c461de47
c07c461de47b57ef1588a2456c70144ef465b90f19559f5c53e8b798fcf0a195

and the Os is still empty

$ sudo podman inspect foo
[
    {
        "Id": "c07c461de47b57ef1588a2456c70144ef465b90f19559f5c53e8b798fcf0a195",
        "Digest": "sha256:ca290537951662f294276a3346af90de401a271290479d33296f33f1e4d6295f",
        "RepoTags": [
            "localhost/foo:latest",
            "localhost/tom:latest"
        ],
        "RepoDigests": [
            "localhost/foo@sha256:94ac642a8e25e2c949c5407e45e147cb1930af79ba9535734e87d284c488fdf6",
            "localhost/foo@sha256:ca290537951662f294276a3346af90de401a271290479d33296f33f1e4d6295f",
            "localhost/tom@sha256:94ac642a8e25e2c949c5407e45e147cb1930af79ba9535734e87d284c488fdf6",
            "localhost/tom@sha256:ca290537951662f294276a3346af90de401a271290479d33296f33f1e4d6295f"
        ],
        "Parent": "",
        "Comment": "",
        "Created": "2020-03-14T07:16:42.726255154Z",
        "Config": {
            "Env": [
                "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
                "NODE_VERSION=12.16.1",
                "YARN_VERSION=1.22.0"
            ],
            "Entrypoint": [
                "docker-entrypoint.sh"
            ],
            "Cmd": [
                "node"
            ]
        },
        "Version": "",
        "Author": "",
        "Architecture": "",
        "Os": "",
        "Size": 909063672,

Output of podman version:

Version:            1.8.1
RemoteAPI Version:  1
Go Version:         go1.12.10
OS/Arch:            linux/amd64

Output of podman info --debug:

debug:
  compiler: gc
  git commit: ""
  go version: go1.12.10
  podman version: 1.8.1
host:
  BuildahVersion: 1.14.2
  CgroupVersion: v1
  Conmon:
    package: 'conmon: /usr/libexec/podman/conmon'
    path: /usr/libexec/podman/conmon
    version: 'conmon version 2.0.11, commit: '
  Distribution:
    distribution: ubuntu
    version: "19.10"
  IDMappings:
    gidmap:
    - container_id: 0
      host_id: 1000
      size: 1
    - container_id: 1
      host_id: 100000
      size: 65536
    uidmap:
    - container_id: 0
      host_id: 1000
      size: 1
    - container_id: 1
      host_id: 100000
      size: 65536
  MemFree: 1194098688
  MemTotal: 16521637888
  OCIRuntime:
    name: runc
    package: 'containerd.io: /usr/bin/runc'
    path: /usr/bin/runc
    version: |-
      runc version 1.0.0-rc10
      commit: dc9208a3303feef5b3839f4323d9beb36df0a9dd
      spec: 1.0.1-dev
  SwapFree: 1546010624
  SwapTotal: 2147479552
  arch: amd64
  cpus: 8
  eventlogger: journald
  hostname: vertin-x1
  kernel: 5.3.0-40-generic
  os: linux
  rootless: true
  slirp4netns:
    Executable: /usr/bin/slirp4netns
    Package: 'slirp4netns: /usr/bin/slirp4netns'
    Version: |-
      slirp4netns version 0.4.3
      commit: unknown
  uptime: 41h 17m 14.3s (Approximately 1.71 days)
registries:
  search:
  - docker.io
  - quay.io
store:
  ConfigFile: /home/vertti/.config/containers/storage.conf
  ContainerStore:
    number: 0
  GraphDriverName: overlay
  GraphOptions:
    overlay.mount_program:
      Executable: /usr/bin/fuse-overlayfs
      Package: 'fuse-overlayfs: /usr/bin/fuse-overlayfs'
      Version: |-
        fusermount3 version: 3.4.1
        fuse-overlayfs: version 0.7.6
        FUSE library version 3.4.1
        using FUSE kernel interface version 7.27
  GraphRoot: /home/vertti/.local/share/containers/storage
  GraphStatus:
    Backing Filesystem: extfs
    Native Overlay Diff: "false"
    Supports d_type: "true"
    Using metacopy: "false"
  ImageStore:
    number: 3
  RunRoot: /run/user/1000/containers
  VolumePath: /home/vertti/.local/share/containers/storage/volumes

Package info (e.g. output of rpm -q podman or apt list podman):

podman/unknown,now 1.8.1~1 amd64 [installed]
podman/unknown 1.8.1~1 arm64
podman/unknown 1.8.1~1 armhf

Additional environment details (AWS, VirtualBox, physical, etc.):
Running podman with sudo on ubuntu 19.10

[baude]

im looking into this ... i have determined that podman build is not setting the field. it is not inspect which was my first concern.

[baude]

@vertti if you can try the PR and report back, that is always helpful.

[vertti]

Thanks, I will take the fix for a spin! But why isn't everyone using OpenShift stumbled to this issue? What are they using to get their custom containers to run on OpenShift? I must be missing something here..

[danielvaughan]

This seems to be have introduced with a more aggressive check for os in

https://github.com/containers/image/blob/d66f61bca2276786c2362ee33113dbb8f6012299/copy/copy.go

added on 22nd Nov 2019. The check stopped raising an error on 31st Jan 2020. Perhaps OpenShift is using code from this window?