Linux permissions are ignored when running write operation

[Stefan9283]

Version

24.0.1

Platform

x86_64

Subsystem

No response

What steps will reproduce the bug?

Run an image build like so with the attached files

docker build . --progress=plain --no-cache 

reproducer.zip

How often does it reproduce? Is there a required condition?

There is no condition. It manifests itself on every run.

What is the expected behavior? Why is that the expected behavior?

Writing on a readonly file should fail.

What do you see instead?

Here's a file with the output I'm getting.

Additional information

• Other images I have tested node on (with precompiled binaries): ubuntu:24.04, public.ecr.aws/amazonlinux/amazonlinux:2023
• Docker Version: 25.0.8, build 0bab007
• this bug causes the following 2 tests to fail:
  • "should throw an error when the file is non readable" in test/parallel/test-config-file.js
  • "database backup fails when dest file is not writable" in test/parallel/test-sqlite-backup.mjs

[bnoordhuis]

Does it happen outside docker? Docker does some funky overlayfs stuff and doesn't always do it right.

[bnoordhuis]

No follow-up and as it's almost certainly a docker bug (not the first time it's been reported) I'm going to go ahead and close this.

[Stefan9283]

Hi! Yes, it seems to be an issue with Docker specifically. I tested it on bare metal and the tests are now behaving as expected. Thank you