projectatomic / oci-systemd-hook

OCI hook to enable running systemd in a container
GNU General Public License v3.0
64 stars 26 forks source link

-v container propagates cgroup mounts to other containers #95

Open aalba6675 opened 6 years ago

aalba6675 commented 6 years ago

All using podman.

  1. Start a container Alice that doesn't use -v
    ## Alice:
    cgroup on /sys/fs/cgroup/systemd/libpod_parent/libpod-9075fe81752a0a9383e587ba9af6de76d546cfec3f3d23683d1de165c69ed96f/ctr type cgroup (rw,nosuid,nodev,noexec,relatime,seclabel,xattr,name=systemd)
  2. Start container Bobby using -v(notice the weird doubled path, and that these mounts are on the host and not the container):
    ## Host:
    cgroup on /sys/fs/cgroup/systemd/libpod_parent/libpod-9ffaff1cdcab235dc1dabdb25d6d1e209f044957b02b533874e0aaf17c0200db/ctr type cgroup (rw,nosuid,nodev,noexec,relatime,seclabel,xattr,name=systemd)
    cgroup on /sys/fs/cgroup/systemd/libpod_parent/libpod-9ffaff1cdcab235dc1dabdb25d6d1e209f044957b02b533874e0aaf17c0200db/ctr type cgroup (rw,nosuid,nodev,noexec,relatime,seclabel,xattr,name=systemd)
    cgroup on /sys/fs/cgroup/systemd/libpod_parent/libpod-9ffaff1cdcab235dc1dabdb25d6d1e209f044957b02b533874e0aaf17c0200db/ctr/libpod_parent/libpod-9ffaff1cdcab235dc1dabdb25d6d1e209f044957b02b533874e0aaf17c0200db/ctr type cgroup (rw,nosuid,nodev,noexec,relatime,seclabel,xattr,name=systemd)
    ## Bobby:
    cgroup on /sys/fs/cgroup/systemd/libpod_parent/libpod-9ffaff1cdcab235dc1dabdb25d6d1e209f044957b02b533874e0aaf17c0200db/ctr type cgroup (rw,nosuid,nodev,noexec,relatime,seclabel,xattr,name=systemd)
  3. Go back to Alice:
    cgroup on /sys/fs/cgroup/systemd/libpod_parent/libpod-9075fe81752a0a9383e587ba9af6de76d546cfec3f3d23683d1de165c69ed96f/ctr type cgroup (rw,nosuid,nodev,noexec,relatime,seclabel,xattr,name=systemd)
    cgroup on /sys/fs/cgroup/systemd/libpod_parent/libpod-9ffaff1cdcab235dc1dabdb25d6d1e209f044957b02b533874e0aaf17c0200db/ctr type cgroup (rw,nosuid,nodev,noexec,relatime,seclabel,xattr,name=systemd)
    cgroup on /sys/fs/cgroup/systemd/libpod_parent/libpod-9ffaff1cdcab235dc1dabdb25d6d1e209f044957b02b533874e0aaf17c0200db/ctr type cgroup (rw,nosuid,nodev,noexec,relatime,seclabel,xattr,name=systemd)
    cgroup on /sys/fs/cgroup/systemd/libpod_parent/libpod-9ffaff1cdcab235dc1dabdb25d6d1e209f044957b02b533874e0aaf17c0200db/ctr/libpod_parent/libpod-9ffaff1cdcab235dc1dabdb25d6d1e209f044957b02b533874e0aaf17c0200db/ctr type cgroup (rw,nosuid,nodev,noexec,relatime,seclabel,xattr,name=systemd)

Observe that Bobby's host mounts have propagated to Alice.