Wrong permissions when creating local files

[juan-carvajal]

Bug Description

Hello! I believe I have found a bug.
This is my config:

{
  "target": {
    "path": "deploy/service",
    "namespace": "ns"
  },
  "feature": {
    "env": {
      "override": {
        "CONFIG_LOCATION": "config/config.evd.toml",
        "RESOURCES_LOCATION": "resources/environment",
        "DATASCIENCE_SECRET_LOCATION": ".env.service-secret",
        "MONGODB_HOST": "ds-model-management-mongodb"
      }
    },
    "fs": "localwithoverrides",
    "network": true
  },
  "kubeconfig": "~/.kube/config",
  "kube_context": "random-context",
  "agent": {
    "log_level": "debug",
    "json_log": false,
    "namespace": "ns",
    "image": "ghcr.io/metalbear-co/mirrord:latest",
    "image_pull_policy": "IfNotPresent",
    "image_pull_secrets": [],
    "ttl": 30,
    "ephemeral": false,
    "communication_timeout": 30,
    "startup_timeout": 360,
    "network_interface": "eth0",
    "flush_connections": false
  }
}

My service is creating a file like this (Go code):

func CopyFile(ctx context.Context, source string, targetFolder string, targetFileName string) (string, error) {
	logger := stlog.LoggerFromContext(ctx)
	_ = Mkdir(targetFolder)
	input, err := os.ReadFile(source)
	if err != nil {
		return "", err
	}

	target := path.Join(targetFolder, targetFileName)
	err = os.WriteFile(target, input, 0644)
	if err != nil {
		logger.ErrorContext(ctx, "Error creating file", slog.String("file", target), slog.Any("error", err))
		return "", err
	}
	return target, nil
}

Please notice the 0644 permission, this means r/w for owner, read for everyone else.
The file is indeed being created, but it appears to have wrong permission after this operation.
A few function calls later, my code attemps to read the file and get permission denied. I tried inspecting the file with cat, permission denied too.
After inspecting the file permissions with ls -l and stat:

juan-popos@pop-os:~/Projects/slb/mlops-model-management/SKLearnServer/1729115711548380409/workspace/code/.s2i$ ls -l
total 4
--w--w-r-T 1 juan-popos juan-popos 70 Oct 16 16:57 environment
juan-popos@pop-os:~/Projects/slb/mlops-model-management/SKLearnServer/1729115711548380409/workspace/code/.s2i$ sudo stat environment
[sudo] password for juan-popos: 
  File: environment
  Size: 70        	Blocks: 8          IO Block: 4096   regular file
Device: fc01h/64513d	Inode: 23869201    Links: 1
Access: (1224/--w--w-r-T)  Uid: ( 1000/juan-popos)   Gid: ( 1000/juan-popos)
Access: 2024-10-16 16:56:35.483446863 -0500
Modify: 2024-10-16 16:57:04.565891017 -0500
Change: 2024-10-16 16:57:04.565891017 -0500
 Birth: 2024-10-16 16:56:35.483446863 -0500

Final permission is 1224/--w--w-r-T:

Why is this file being created with wrong permission?

Steps to Reproduce

1. Setup mirrord with localwithoverrides fs.
2. Using Golang, create a file with os.WriteFile, use perm 0644.
3. try to read the newly created file (you will get an error).
4. Examine file permissions with ls -l or stat (you will need sudo for this one). The resulting permission will be 1224/--w--w-r-T. This behavior seems unexpected.

Backtrace

No response

mirrord layer logs

No response

Internal proxy logs

No response

Your operating system and version

Pop!_OS 22.04 LTS x86_64 (kernel 6.9.3-76060903-generic)

Local process

Go 1.22.7 linux/amd64

Local process version

Go 1.22.7 linux/amd64

Additional Info

No response

[linear]

MBE-481 Wrong permissions when creating local files

[aviramha]

Thanks for reporting!
Probably #2614

[aviramha]

Closing in favor of #2614