Use dumb-init from Ubuntu repositories

dumb-init is available in the Ubuntu package repositories, so let's use
that. This makes adding new architectures easier.

For Ubuntu 20.04, this means a downgrade from 1.2.5 to 1.2.2. However,
given that Ubuntu 20.04 reached the end of its support cycle in May
2025, this seems acceptable. The only regression is that dumb-init
won't attempt to cd into the root directory in order to release the file
descriptor for its current working directory, besides some fixes around
the --help and --version flags.

Signed-off-by: Tom Wieczorek <twieczorek@mirantis.com>

runner/actions-runner-dind-rootless.ubuntu-20.04.dockerfile

@@ -6,7 +6,6 @@ ARG RUNNER_CONTAINER_HOOKS_VERSION
 # Docker and Docker Compose arguments
 ENV CHANNEL=stable
 ARG DOCKER_COMPOSE_VERSION=v2.23.0
-ARG DUMB_INIT_VERSION=1.2.5
 
 # Other arguments
 ARG DEBUG=false
@@ -25,6 +24,7 @@ RUN apt-get update -y \
     ca-certificates \
     curl \
     dnsutils \
+    dumb-init \
     ftp \
     git \
     iproute2 \
@@ -71,12 +71,6 @@ RUN set -eux; \
     echo 'dockremap:165536:65536' >> /etc/subuid; \
     echo 'dockremap:165536:65536' >> /etc/subgid
 
-RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -fLo /usr/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
-    && chmod +x /usr/bin/dumb-init
-
 ENV RUNNER_ASSETS_DIR=/runnertmp
 RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
     && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "x86_64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x64 ; fi \

runner/actions-runner-dind-rootless.ubuntu-22.04.dockerfile

@@ -6,7 +6,6 @@ ARG RUNNER_CONTAINER_HOOKS_VERSION
 # Docker and Docker Compose arguments
 ENV CHANNEL=stable
 ARG DOCKER_COMPOSE_VERSION=v2.23.0
-ARG DUMB_INIT_VERSION=1.2.5
 ARG RUNNER_USER_UID=1001
 
 # Other arguments
@@ -22,6 +21,7 @@ RUN apt-get update -y \
     && apt-get install -y --no-install-recommends \
     ca-certificates \
     curl \
+    dumb-init \
     fuse-overlayfs \
     git \
     iproute2 \
@@ -49,12 +49,6 @@ RUN set -eux; \
     echo 'dockremap:165536:65536' >> /etc/subuid; \
     echo 'dockremap:165536:65536' >> /etc/subgid
 
-RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -fLo /usr/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
-    && chmod +x /usr/bin/dumb-init
-
 ENV RUNNER_ASSETS_DIR=/runnertmp
 RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
     && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "x86_64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x64 ; fi \

runner/actions-runner-dind-rootless.ubuntu-24.04.dockerfile

@@ -6,7 +6,6 @@ ARG RUNNER_CONTAINER_HOOKS_VERSION
 # Docker and Docker Compose arguments
 ENV CHANNEL=stable
 ARG DOCKER_COMPOSE_VERSION=v2.23.0
-ARG DUMB_INIT_VERSION=1.2.5
 ARG RUNNER_USER_UID=1001
 
 # Other arguments
@@ -22,6 +21,7 @@ RUN apt-get update -y \
     && apt-get install -y --no-install-recommends \
     ca-certificates \
     curl \
+    dumb-init \
     fuse-overlayfs \
     git \
     iproute2 \
@@ -49,12 +49,6 @@ RUN set -eux; \
     echo 'dockremap:165536:65536' >> /etc/subuid; \
     echo 'dockremap:165536:65536' >> /etc/subgid
 
-RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -fLo /usr/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
-    && chmod +x /usr/bin/dumb-init
-
 ENV RUNNER_ASSETS_DIR=/runnertmp
 RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
     && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "x86_64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x64 ; fi \

runner/actions-runner-dind.ubuntu-20.04.dockerfile

@@ -7,7 +7,6 @@ ARG RUNNER_CONTAINER_HOOKS_VERSION
 ARG CHANNEL=stable
 ARG DOCKER_VERSION=24.0.7
 ARG DOCKER_COMPOSE_VERSION=v2.23.0
-ARG DUMB_INIT_VERSION=1.2.5
 
 # Use 1001 and 121 for compatibility with GitHub-hosted runners
 ARG RUNNER_UID=1000
@@ -23,6 +22,7 @@ RUN apt-get update -y \
     ca-certificates \
     curl \
     dnsutils \
+    dumb-init \
     ftp \
     git \
     iproute2 \
@@ -66,12 +66,6 @@ RUN adduser --disabled-password --gecos "" --uid $RUNNER_UID runner \
 
 ENV HOME=/home/runner
 
-RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -fLo /usr/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
-    && chmod +x /usr/bin/dumb-init
-
 ENV RUNNER_ASSETS_DIR=/runnertmp
 RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
     && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "x86_64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x64 ; fi \

runner/actions-runner-dind.ubuntu-22.04.dockerfile

@@ -7,7 +7,6 @@ ARG RUNNER_CONTAINER_HOOKS_VERSION
 ARG CHANNEL=stable
 ARG DOCKER_VERSION=24.0.7
 ARG DOCKER_COMPOSE_VERSION=v2.23.0
-ARG DUMB_INIT_VERSION=1.2.5
 ARG RUNNER_USER_UID=1001
 ARG DOCKER_GROUP_GID=121
 
@@ -19,6 +18,7 @@ RUN apt-get update -y \
     && apt-get install -y --no-install-recommends \
     ca-certificates \
     curl \
+    dumb-init \
     git \
     iptables \
     jq \
@@ -42,12 +42,6 @@ RUN adduser --disabled-password --gecos "" --uid $RUNNER_USER_UID runner \
 
 ENV HOME=/home/runner
 
-RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -fLo /usr/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
-    && chmod +x /usr/bin/dumb-init
-
 ENV RUNNER_ASSETS_DIR=/runnertmp
 RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
     && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "x86_64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x64 ; fi \

runner/actions-runner-dind.ubuntu-24.04.dockerfile

@@ -7,7 +7,6 @@ ARG RUNNER_CONTAINER_HOOKS_VERSION
 ARG CHANNEL=stable
 ARG DOCKER_VERSION=24.0.7
 ARG DOCKER_COMPOSE_VERSION=v2.23.0
-ARG DUMB_INIT_VERSION=1.2.5
 ARG RUNNER_USER_UID=1001
 ARG DOCKER_GROUP_GID=121
 
@@ -19,6 +18,7 @@ RUN apt-get update -y \
     && apt-get install -y --no-install-recommends \
     ca-certificates \
     curl \
+    dumb-init \
     git \
     iptables \
     jq \
@@ -42,12 +42,6 @@ RUN adduser --disabled-password --gecos "" --uid $RUNNER_USER_UID runner \
 
 ENV HOME=/home/runner
 
-RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -fLo /usr/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
-    && chmod +x /usr/bin/dumb-init
-
 ENV RUNNER_ASSETS_DIR=/runnertmp
 RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
     && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "x86_64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x64 ; fi \

runner/actions-runner.ubuntu-20.04.dockerfile

@@ -7,7 +7,6 @@ ARG RUNNER_CONTAINER_HOOKS_VERSION
 ARG CHANNEL=stable
 ARG DOCKER_VERSION=24.0.7
 ARG DOCKER_COMPOSE_VERSION=v2.23.0
-ARG DUMB_INIT_VERSION=1.2.5
 
 # Use 1001 and 121 for compatibility with GitHub-hosted runners
 ARG RUNNER_UID=1000
@@ -23,6 +22,7 @@ RUN apt-get update -y \
     ca-certificates \
     curl \
     dnsutils \
+    dumb-init \
     ftp \
     git \
     iproute2 \
@@ -62,12 +62,6 @@ RUN adduser --disabled-password --gecos "" --uid $RUNNER_UID runner \
 
 ENV HOME=/home/runner
 
-RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -fLo /usr/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
-    && chmod +x /usr/bin/dumb-init
-
 ENV RUNNER_ASSETS_DIR=/runnertmp
 RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
     && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "x86_64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x64 ; fi \

runner/actions-runner.ubuntu-22.04.dockerfile

@@ -7,7 +7,6 @@ ARG RUNNER_CONTAINER_HOOKS_VERSION
 ARG CHANNEL=stable
 ARG DOCKER_VERSION=24.0.7
 ARG DOCKER_COMPOSE_VERSION=v2.23.0
-ARG DUMB_INIT_VERSION=1.2.5
 ARG RUNNER_USER_UID=1001
 ARG DOCKER_GROUP_GID=121
 
@@ -19,6 +18,7 @@ RUN apt-get update -y \
     && apt-get install -y --no-install-recommends \
     ca-certificates \
     curl \
+    dumb-init \
     git \
     jq \
     sudo \
@@ -39,12 +39,6 @@ RUN adduser --disabled-password --gecos "" --uid $RUNNER_USER_UID runner \
 
 ENV HOME=/home/runner
 
-RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -fLo /usr/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
-    && chmod +x /usr/bin/dumb-init
-
 ENV RUNNER_ASSETS_DIR=/runnertmp
 RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
     && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "x86_64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x64 ; fi \

runner/actions-runner.ubuntu-24.04.dockerfile

@@ -7,7 +7,6 @@ ARG RUNNER_CONTAINER_HOOKS_VERSION
 ARG CHANNEL=stable
 ARG DOCKER_VERSION=24.0.7
 ARG DOCKER_COMPOSE_VERSION=v2.23.0
-ARG DUMB_INIT_VERSION=1.2.5
 ARG RUNNER_USER_UID=1001
 ARG DOCKER_GROUP_GID=121
 
@@ -19,6 +18,7 @@ RUN apt-get update -y \
     && apt-get install -y --no-install-recommends \
     ca-certificates \
     curl \
+    dumb-init \
     git \
     jq \
     sudo \
@@ -39,12 +39,6 @@ RUN adduser --disabled-password --gecos "" --uid $RUNNER_USER_UID runner \
 
 ENV HOME=/home/runner
 
-RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
-    && if [ "$ARCH" = "arm64" ]; then export ARCH=aarch64 ; fi \
-    && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x86_64 ; fi \
-    && curl -fLo /usr/bin/dumb-init https://github.com/Yelp/dumb-init/releases/download/v${DUMB_INIT_VERSION}/dumb-init_${DUMB_INIT_VERSION}_${ARCH} \
-    && chmod +x /usr/bin/dumb-init
-
 ENV RUNNER_ASSETS_DIR=/runnertmp
 RUN export ARCH=$(echo ${TARGETPLATFORM} | cut -d / -f2) \
     && if [ "$ARCH" = "amd64" ] || [ "$ARCH" = "x86_64" ] || [ "$ARCH" = "i386" ]; then export ARCH=x64 ; fi \