docker-in-docker feature fails on macOS ARM64 with containerd 2.3.x unless erofs-utils is installed

[cumhuronat]

Summary

The ghcr.io/devcontainers/features/docker-in-docker:2 feature failed to start the inner Docker daemon on macOS Apple Silicon with the mcr.microsoft.com/devcontainers/dotnet:1-10.0 base image.

Inside the devcontainer, docker ps failed with:

Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?
dockerd was launched, and containerd started, but dockerd timed out waiting for containerd:

failed to start containerd: timeout waiting for containerd to start

The relevant containerd log included:

failed to check mkfs.erofs availability: failed to run mkfs.erofs --help: exec: "mkfs.erofs": executable file not found in $PATH: skip plugin
no plugins registered for io.containerd.transfer.v1: plugin: not found

Installing erofs-utils in the devcontainer image fixed the issue:

RUN apt-get update \
    && apt-get install -y --no-install-recommends \
        protobuf-compiler \
        erofs-utils \
    && rm -rf /var/lib/apt/lists/*

Environment

Host: macOS Apple Silicon
Docker Desktop: 4.72.0
Docker Engine: 29.4.2
Dev Containers extension: 0.459.0
VS Code: 1.119.0
Base image: mcr.microsoft.com/devcontainers/dotnet:1-10.0
Feature: ghcr.io/devcontainers/features/docker-in-docker:2
Architecture inside container: aarch64 / arm64

Expected

The Docker-in-Docker feature should either install erofs-utils, avoid enabling a containerd path that requires mkfs.erofs, or document that base images must include erofs-utils for containerd 2.3.x.

Actual

The inner Docker daemon does not become usable; docker ps reports that it cannot connect to /var/run/docker.sock.

Workaround

Install erofs-utils in the Dockerfile before the feature starts dockerd.