Tasks are failing when "init" is the first argument followed by two or more other arguments.

[vdemeester]

Expected Behavior

Given the following task

apiVersion: tekton.dev/v1beta1
kind: Task
metadata:
  name: tkn-arg-test
  labels:
    app.kubernetes.io/version: "0.4"
  annotations:
    tekton.dev/pipelines.minVersion: "0.22.0"
    tekton.dev/tags: cli
spec:
  description: >-
    Test consuming args
  params:
  - name: ARGS
    description: The terraform cli commands to tun
    type: array
    default:
      - "--help"
  - name: USER_HOME
    description: Override home directory to /tekton/home
    type: string
    default: "/tekton/home"
  steps:
    - name: echo-cli
      image: registry.access.redhat.com/ubi9/ubi-minimal:9.0.0-1580
      workingDir: /tekton/home
      args:
        - "$(params.ARGS)"
      command: ["echo"]
      resources:
       limits:
         cpu: 250m
         memory: 1Gi
       requests:
         cpu: 250m
         memory: 500Mi
      env:
        - name: "HOME"
          value: $(params.USER_HOME)

The following command should work:

$ tkn task start tkn-arg-test "-p=ARGS=init,two" --use-param-defaults --showlog
# Works…
[echo-cli] init two 
$ tkn task start tkn-arg-test "-p=ARGS=init,two,three" --use-param-defaults --showlog
# Doesn't work
[echo-cli] 2022/07/05 17:05:42 init error: open two: no such file or directory

Actual Behavior

It fails as written above

Steps to Reproduce the Problem

• Create the task
• Issue the tkn commands

Additional Info

This affect any Pipeline release that contains the follow change :
#4826. This means it affects 0.32 to 0.37 and the fix should be backport in all.

The main reason why it fails is the way the entrypoint binary is written and the way flag acts. To simplify a tiny bit, the command created on a task looks like /ko-app/entrypoint --entrypoint echo -- command and args here (with a bunch of flags before -- ommited here). With the above example, it becomes /ko-app/entrypoint --entrypoint echo -- init foo bar. The flag package, in that particular case ignores the -- and tells the rest of the code that the arguments are init foo bar, which is similar to /ko-app/entrypoint --entrypoint echo init foo bar. And this, in terms, goes into the init subcommand.

/assign
/priority critical-urgent

[vdemeester]

Upstream go issue, just in case : golang/go#53691