If we find that DNSConfig is provided and empty (not nil), we should not
replace it with the host's resolv.conf.
Also adds tests.
Signed-off-by: Tim Hockin <thockin@google.com>
Prior to this commit, `readOnly` volumes were not recursively read-only and
could result in compromise of data;
e.g., even if `/mnt` was mounted as read-only, its submounts such as
`/mnt/usbstorage` were not read-only.
This commit utilizes runc's "rro" bind mount option to make read-only bind
mounts literally read-only. The "rro" bind mount options is implemented by
calling `mount_setattr(2)` with `MOUNT_ATTR_RDONLY` and `AT_RECURSIVE`.
The "rro" bind mount options requires kernel >= 5.12, with runc >= 1.1 or
a compatible runtime such as crun >= 1.4.
When the "rro" bind mount options is not available, containerd falls back
to the legacy non-recursive read-only mounts by default.
The behavior is configurable via `/etc/containerd/config.toml`:
```toml
version = 2
[plugins."io.containerd.grpc.v1.cri".containerd.runtimes.runc]
# treat_ro_mounts_as_rro ("Enabled"|"IfPossible"|"Disabled")
# treats read-only mounts as recursive read-only mounts.
# An empty string means "IfPossible".
# "Enabled" requires Linux kernel v5.12 or later.
# This configuration does not apply to non-volume mounts such as "/sys/fs/cgroup".
treat_ro_mounts_as_rro = ""
```
Replaces:
- kubernetes/enhancements issue 3857
- kubernetes/enhancements PR 3858
Note: this change does not affect non-CRI clients such as ctr, nerdctl, and Docker/Moby.
RRO mounts have been supported since nerdctl v0.14 (containerd/nerdctl PR 511)
and Docker v25 (moby/moby PR 45278).
Signed-off-by: Akihiro Suda <akihiro.suda.cz@hco.ntt.co.jp>
We should set sandbox CreatedAt first time when we create sandbox struct,
and then set sandbox CreatedAt second time after container started.
Before this commit, we just set sandbox CreatedAt after container
started, but if network create failed, the sandbox time is the
default time, which is 269 years ago, so we need to set sandbox
CreatedAt at first, even if an error occurred before start container.
Signed-off-by: zzzzzzzzzy9 <zhang.yu58@zte.com.cn>
This change simplifies the CRI plugin dependencies by not requiring the
CRI image plugin to depend on any other CRI components. Since other CRI
plugins depend on the image plugin, this allows prevents a dependency
cycle for CRI configurations on a base plugin.
Signed-off-by: Derek McGowan <derek@mcg.dev>
Updates the CRI image service to own image related configuration and
separate it from the runtime configuration.
Signed-off-by: Derek McGowan <derek@mcg.dev>
Prepares the CRI image service for splitting CRI into multiple plugins.
Also prepares for config migration which will spread across multiple
different plugins.
Signed-off-by: Derek McGowan <derek@mcg.dev>
