No IPv6 access in podman build, but works in podman run

[Xiretza]

/kind bug

Description

Commands run from inside podman build have no IPv6 access, while the same commands run from podman run work fine.

Steps to reproduce the issue:

echo -e 'FROM docker.io/archlinux:latest\nRUN curl --verbose --ipv6 https://google.com' | podman build -

Describe the results you received:

STEP 1/2: FROM docker.io/archlinux:latest
STEP 2/2: RUN curl --verbose --ipv6 https://google.com
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:--  0:00:01 --:--:--     0*   Trying 2a00:1450:4016:809::200e:443...
* Immediate connect fail for 2a00:1450:4016:809::200e: Network is unreachable
* Closing connection 0
curl: (7) Couldn't connect to server
Error: error building at STEP "RUN curl --verbose --ipv6 https://google.com": error while running runtime: exit status 7

Describe the results you expected:

The same output as with podman run docker.io/archlinux:latest curl --verbose --ipv6 https://google.com:

  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0*   Trying 2a00:1450:4016:809::200e:443...
* Connected to google.com (2a00:1450:4016:809::200e) port 443 (#0)
[...]

Output of podman version:

Client:       Podman Engine
Version:      4.0.3
API Version:  4.0.3
Go Version:   go1.18
Git Commit:   62534053086fdeba7b93117e7c4dc6e797835a3e
Built:        Mon Apr  4 14:54:02 2022
OS/Arch:      linux/amd64

Output of podman info --debug:

host:
  arch: amd64
  buildahVersion: 1.24.3
  cgroupControllers:
  - memory
  - pids
  cgroupManager: systemd
  cgroupVersion: v2
  conmon:
    package: /usr/bin/conmon is owned by conmon 1:2.1.0-1
    path: /usr/bin/conmon
    version: 'conmon version 2.1.0, commit: bdb4f6e56cd193d40b75ffc9725d4b74a18cb33c'
  cpus: 12
  distribution:
    distribution: arch
    version: unknown
  eventLogger: journald
  hostname: turing
  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
  kernel: 5.17.1-arch1-1
  linkmode: dynamic
  logDriver: journald
  memFree: 3871182848
  memTotal: 16550350848
  networkBackend: cni
  ociRuntime:
    name: crun
    package: /usr/bin/crun is owned by crun 1.4.4-1
    path: /usr/bin/crun
    version: |-
      crun version 1.4.4
      commit: 6521fcc5806f20f6187eb933f9f45130c86da230
      spec: 1.0.0
      +SYSTEMD +SELINUX +APPARMOR +CAP +SECCOMP +EBPF +CRIU +YAJL
  os: linux
  remoteSocket:
    path: /run/user/1000/podman/podman.sock
  security:
    apparmorEnabled: false
    capabilities: CAP_CHOWN,CAP_DAC_OVERRIDE,CAP_FOWNER,CAP_FSETID,CAP_KILL,CAP_NET_BIND_SERVICE,CAP_SETFCAP,CAP_SETGID,CAP_SETPCAP,CAP_SETUID,CAP_SYS_CHROOT
    rootless: true
    seccompEnabled: true
    seccompProfilePath: /etc/containers/seccomp.json
    selinuxEnabled: false
  serviceIsRemote: false
  slirp4netns:
    executable: /usr/bin/slirp4netns
    package: /usr/bin/slirp4netns is owned by slirp4netns 1.1.12-1
    version: |-
      slirp4netns version 1.1.12
      commit: 7a104a101aa3278a2152351a082a6df71f57c9a3
      libslirp: 4.6.1
      SLIRP_CONFIG_VERSION_MAX: 3
      libseccomp: 2.5.3
  swapFree: 0
  swapTotal: 0
  uptime: 51h 24m 12.78s (Approximately 2.12 days)
plugins:
  log:
  - k8s-file
  - none
  - passthrough
  - journald
  network:
  - bridge
  - macvlan
  - ipvlan
  volume:
  - local
registries: {}
store:
  configFile: /home/lambda/.config/containers/storage.conf
  containerStore:
    number: 7
    paused: 0
    running: 0
    stopped: 7
  graphDriverName: overlay
  graphOptions: {}
  graphRoot: /home/lambda/.local/share/containers/storage
  graphStatus:
    Backing Filesystem: btrfs
    Native Overlay Diff: "true"
    Supports d_type: "true"
    Using metacopy: "false"
  imageCopyTmpDir: /var/tmp
  imageStore:
    number: 3
  runRoot: /run/user/1000/containers
  volumePath: /home/lambda/.local/share/containers/storage/volumes
version:
  APIVersion: 4.0.3
  Built: 1649076842
  BuiltTime: Mon Apr  4 14:54:02 2022
  GitCommit: 62534053086fdeba7b93117e7c4dc6e797835a3e
  GoVersion: go1.18
  OsArch: linux/amd64
  Version: 4.0.3

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

$ pacman -Qi podman
Name            : podman
Version         : 4.0.3-1
Description     : Tool and library for running OCI-based containers in pods
Architecture    : x86_64
URL             : https://github.com/containers/podman
Licenses        : Apache
Groups          : None
Provides        : None
Depends On      : conmon  containers-common  crun  iptables  libdevmapper.so=1.02-64  libgpgme.so=11-64  libseccomp.so=2-64  slirp4netns
Optional Deps   : apparmor: for AppArmor support
                  btrfs-progs: support btrfs backend devices [installed]
                  catatonit: --init flag support
                  netavark: for a new container-network-stack implementation
                  podman-compose: for docker-compose compatibility
                  podman-docker: for Docker-compatible CLI
Required By     : None
Optional For    : None
Conflicts With  : None
Replaces        : None
Installed Size  : 67.98 MiB
Packager        : David Runge <[email protected]>
Build Date      : 2022-04-04T14:54:02 CEST
Install Date    : 2022-04-04T19:22:55 CEST
Install Reason  : Explicitly installed
Install Script  : No
Validated By    : Signature

Have you tested with the latest version of Podman and have you checked the Podman Troubleshooting Guide? (https://github.com/containers/podman/blob/main/troubleshooting.md)

Yes

[Luap99]

Do you run podman as rootless?

[Xiretza]

Yes - interestingly, when running podman run as root, then not even DNS works (neither for v4 nor v6), but I think that's a different issue.

[Luap99]

IPv6 is not enabled on the default network. For rootless we set the slirp4netns settings to incalude enable_ipv6 by default, however buildah does not use these settings.

[Xiretza]

I see. Is it possible to make buildah set that too? Should I go and open an issue in https://github.com/containers/buildah/?

[Luap99]

You do not have to report this in buildah, we can move the issue there.

The only workaround I can think of is replacing the slirp4netns binary with a script that calls slirp4netns --enable-ipv6 ... Otherwise you have to wait until we fix it.

[github-actions[bot]]

A friendly reminder that this issue had no activity for 30 days.

[rhatdan]

@flouthoc PTAL

[flouthoc]

@Xiretza You can use buildah build --network=host ... to make this work however I agree we should support enable-ipv6 by default as well for private rootless network with slirp4netns so following PR should add that feature: https://github.com/containers/buildah/pull/3969

[github-actions[bot]]

A friendly reminder that this issue had no activity for 30 days.

[rhatdan]

@flouthoc DId you ever make this change?

[github-actions[bot]]

A friendly reminder that this issue had no activity for 30 days.

[flouthoc]

Yet to visit this again.

[github-actions[bot]]

A friendly reminder that this issue had no activity for 30 days.

[github-actions[bot]]

A friendly reminder that this issue had no activity for 30 days.

[github-actions[bot]]

A friendly reminder that this issue had no activity for 30 days.

[sanmai-NL]

Not stale

[rhatdan]

@flouthoc need you to look at this?

[Luap99]

I will take this, I plan to move most podman networking code to c/common. Then I can integrate this here as well, my motivation is mostly adding pasta support but this should also result in allowing buildah to set slirp4netns options.