Wrong platform after updating Docker Desktop to the latest version

[iSerganov]

Description

Before the Docker Desktop update to version 4.37.2 (179585) building a docker image from a Dockerfile like below:

FROM my/custom/image:latest
...

and running docker build . resulted in an image with the same platform as my/custom/image:latest has.

However now the docker takes a platform from the host (the local machine or virtual host where the build is called).

So now it is required to explicitly define the platform:

docker build --platform=linux/amd64 .

Why was that changed?

Reproduce

1. On a Mac with arm64 architecture, create the Dockerfile as below:

FROM your/custom/image-which-is-available-with-amd64-arch-only:latest
...

2. Run docker build .
3. Check the image platform - it will be the same as your Mac has - arm64

Expected behavior

The platform of the build image should be linux/amd64 - the same as your/custom/image-which-is-available-with-amd64-arch-only:latest has.

docker version

Client:
 Version:           27.4.0
 API version:       1.47
 Go version:        go1.22.10
 Git commit:        bde2b89
 Built:             Sat Dec  7 10:35:43 2024
 OS/Arch:           darwin/arm64
 Context:           desktop-linux

Server: Docker Desktop 4.37.2 (179585)
 Engine:
  Version:          27.4.0
  API version:      1.47 (minimum version 1.24)
  Go version:       go1.22.10
  Git commit:       92a8393
  Built:            Sat Dec  7 10:38:33 2024
  OS/Arch:          linux/arm64
  Experimental:     false
 containerd:
  Version:          1.7.21
  GitCommit:        472731909fa34bd7bc9c087e4c27943f9835f111
 runc:
  Version:          1.1.13
  GitCommit:        v1.1.13-0-g58aa920
 docker-init:
  Version:          0.19.0
  GitCommit:        de40ad0

docker info

Client:
 Version:    27.4.0
 Context:    desktop-linux
 Debug Mode: false
 Plugins:
  ai: Ask Gordon - Docker Agent (Docker Inc.)
    Version:  v0.5.1
    Path:    
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.19.2-desktop.1
    Path:    
  compose: Docker Compose (Docker Inc.)
    Version:  v2.31.0-desktop.2
    Path:     
  debug: Get a shell into any image or container (Docker Inc.)
    Version:  0.0.37
    Path:     
  desktop: Docker Desktop commands (Beta) (Docker Inc.)
    Version:  v0.1.0
    Path:     
  dev: Docker Dev Environments (Docker Inc.)
    Version:  v0.1.2
    Path:     
  extension: Manages Docker extensions (Docker Inc.)
    Version:  v0.2.27
    Path:     
  feedback: Provide feedback, right in your terminal! (Docker Inc.)
    Version:  v1.0.5
    Path:     
  init: Creates Docker-related starter files for your project (Docker Inc.)
    Version:  v1.4.0
    Path:    
  sbom: View the packaged-based Software Bill Of Materials (SBOM) for an image (Anchore Inc.)
    Version:  0.6.0
    Path:    
  scout: Docker Scout (Docker Inc.)
    Version:  v1.15.1
    Path:     

Server:
 Containers: 0
  Running: 0
  Paused: 0
  Stopped: 0
 Images: 2
 Server Version: 27.4.0
 Storage Driver: overlayfs
  driver-type: io.containerd.snapshotter.v1
 Logging Driver: json-file
 Cgroup Driver: cgroupfs
 Cgroup Version: 2
 Plugins:
  Volume: local
  Network: bridge host ipvlan macvlan null overlay
  Log: awslogs fluentd gcplogs gelf journald json-file local splunk syslog
 CDI spec directories:
  /etc/cdi
  /var/run/cdi
 Swarm: inactive
 Runtimes: io.containerd.runc.v2 runc
 Default Runtime: runc
 Init Binary: docker-init
 containerd version: 472731909fa34bd7bc9c087e4c27943f9835f111
 runc version: v1.1.13-0-g58aa920
 init version: de40ad0
 Security Options:
  seccomp
   Profile: unconfined
  cgroupns
 Kernel Version: 6.10.14-linuxkit
 Operating System: Docker Desktop
 OSType: linux
 Architecture: aarch64
 CPUs: 16
 Total Memory: 7.653GiB
 Name: docker-desktop
 ID: 67e2a081-9320-4657-adc4-7fa830a0cccf
 Docker Root Dir: /var/lib/docker
 Debug Mode: false
 HTTP Proxy: http.docker.internal:3128
 HTTPS Proxy: http.docker.internal:3128
 No Proxy: hubproxy.docker.internal
 Experimental: false
 Insecure Registries:
  hubproxy.docker.internal:5555
  127.0.0.0/8
 Live Restore Enabled: false

Diagnostics ID

AC3A1A71-D1F5-4F58-9230-50C0D00531EB/20250129033356

Additional Info

No response