Files
act_runner/act/filecollector/file_collector_test.go
Nicolas 3ea7d39690 fix: overwrite read-only files when copying action directories (#942)
## Summary

  - `CopyCollector.WriteFile` now removes any existing destination file
    before writing, handling read-only modes (e.g. git pack files at
    `0444`) that cause `EACCES`/`ERROR_ACCESS_DENIED` on macOS and Windows.
  - Added `O_TRUNC` to the `OpenFile` flags as a safety net.

  ## Root cause

  When a composite action with a post step runs on a host runner,
  `runPostStep` calls `maybeCopyToActionDir`, which re-copies the action
  into `miscpath/act/actions/<name>/`. The first copy (main step) writes
  `.git/objects/pack/*.idx` at the destination with mode `0444` (as set
  by go-git). The second copy (post step) calls
  `os.OpenFile(dest, O_CREATE|O_WRONLY, …)` on that existing `0444` file,
  which fails immediately:

  - macOS: `open <path>: permission denied`
  - Windows: `open <path>: Access is denied`

Fixes: https://gitea.com/gitea/runner/issues/941
Fixes: https://gitea.com/gitea/runner/issues/876

---------

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: silverwind <2021+silverwind@noreply.gitea.com>
Reviewed-on: https://gitea.com/gitea/runner/pulls/942
Reviewed-by: silverwind <2021+silverwind@noreply.gitea.com>
Co-authored-by: Nicolas <bircni@icloud.com>
Co-committed-by: Nicolas <bircni@icloud.com>
2026-05-08 04:11:42 +00:00

224 lines
7.0 KiB
Go

// Copyright 2024 The Gitea Authors. All rights reserved.
// Copyright 2024 The nektos/act Authors. All rights reserved.
// SPDX-License-Identifier: MIT
package filecollector
import (
"archive/tar"
"context"
"io"
"os"
"path/filepath"
"runtime"
"strings"
"testing"
"github.com/go-git/go-billy/v5"
"github.com/go-git/go-billy/v5/memfs"
git "github.com/go-git/go-git/v5"
"github.com/go-git/go-git/v5/plumbing/cache"
"github.com/go-git/go-git/v5/plumbing/format/gitignore"
"github.com/go-git/go-git/v5/plumbing/format/index"
"github.com/go-git/go-git/v5/storage/filesystem"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
)
type memoryFs struct {
billy.Filesystem
}
func (mfs *memoryFs) walk(root string, fn filepath.WalkFunc) error {
dir, err := mfs.ReadDir(root)
if err != nil {
return err
}
for i := range dir {
filename := filepath.Join(root, dir[i].Name())
err = fn(filename, dir[i], nil)
if dir[i].IsDir() {
if err == filepath.SkipDir {
err = nil
} else if err := mfs.walk(filename, fn); err != nil {
return err
}
}
if err != nil {
return err
}
}
return nil
}
func (mfs *memoryFs) Walk(root string, fn filepath.WalkFunc) error {
stat, err := mfs.Lstat(root)
if err != nil {
return err
}
err = fn(strings.Join([]string{root, "."}, string(filepath.Separator)), stat, nil)
if err != nil {
return err
}
return mfs.walk(root, fn)
}
func (mfs *memoryFs) OpenGitIndex(path string) (*index.Index, error) {
f, _ := mfs.Filesystem.Chroot(filepath.Join(path, ".git")) //nolint:staticcheck // pre-existing issue from nektos/act
storage := filesystem.NewStorage(f, cache.NewObjectLRUDefault())
i, err := storage.Index()
if err != nil {
return nil, err
}
return i, nil
}
func (mfs *memoryFs) Open(path string) (io.ReadCloser, error) {
return mfs.Filesystem.Open(path)
}
func (mfs *memoryFs) Readlink(path string) (string, error) {
return mfs.Filesystem.Readlink(path)
}
func TestIgnoredTrackedfile(t *testing.T) {
fs := memfs.New()
_ = fs.MkdirAll("mygitrepo/.git", 0o777)
dotgit, _ := fs.Chroot("mygitrepo/.git")
worktree, _ := fs.Chroot("mygitrepo")
repo, _ := git.Init(filesystem.NewStorage(dotgit, cache.NewObjectLRUDefault()), worktree)
f, _ := worktree.Create(".gitignore")
_, _ = f.Write([]byte(".*\n"))
f.Close()
// This file shouldn't be in the tar
f, _ = worktree.Create(".env")
_, _ = f.Write([]byte("test=val1\n"))
f.Close()
w, _ := repo.Worktree()
// .gitignore is in the tar after adding it to the index
_, _ = w.Add(".gitignore")
tmpTar, _ := fs.Create("temp.tar")
tw := tar.NewWriter(tmpTar)
ps, _ := gitignore.ReadPatterns(worktree, []string{})
ignorer := gitignore.NewMatcher(ps)
fc := &FileCollector{
Fs: &memoryFs{Filesystem: fs},
Ignorer: ignorer,
SrcPath: "mygitrepo",
SrcPrefix: "mygitrepo" + string(filepath.Separator),
Handler: &TarCollector{
TarWriter: tw,
},
}
err := fc.Fs.Walk("mygitrepo", fc.CollectFiles(context.Background(), []string{}))
assert.NoError(t, err, "successfully collect files") //nolint:testifylint // pre-existing issue from nektos/act
tw.Close()
_, _ = tmpTar.Seek(0, io.SeekStart)
tr := tar.NewReader(tmpTar)
h, err := tr.Next()
assert.NoError(t, err, "tar must not be empty") //nolint:testifylint // pre-existing issue from nektos/act
assert.Equal(t, ".gitignore", h.Name)
_, err = tr.Next()
assert.ErrorIs(t, err, io.EOF, "tar must only contain one element")
}
func TestSymlinks(t *testing.T) {
fs := memfs.New()
_ = fs.MkdirAll("mygitrepo/.git", 0o777)
dotgit, _ := fs.Chroot("mygitrepo/.git")
worktree, _ := fs.Chroot("mygitrepo")
repo, _ := git.Init(filesystem.NewStorage(dotgit, cache.NewObjectLRUDefault()), worktree)
// This file shouldn't be in the tar
f, err := worktree.Create(".env")
assert.NoError(t, err) //nolint:testifylint // pre-existing issue from nektos/act
_, err = f.Write([]byte("test=val1\n"))
assert.NoError(t, err) //nolint:testifylint // pre-existing issue from nektos/act
f.Close()
err = worktree.Symlink(".env", "test.env")
assert.NoError(t, err) //nolint:testifylint // pre-existing issue from nektos/act
w, err := repo.Worktree()
assert.NoError(t, err) //nolint:testifylint // pre-existing issue from nektos/act
// .gitignore is in the tar after adding it to the index
_, err = w.Add(".env")
assert.NoError(t, err) //nolint:testifylint // pre-existing issue from nektos/act
_, err = w.Add("test.env")
assert.NoError(t, err) //nolint:testifylint // pre-existing issue from nektos/act
tmpTar, _ := fs.Create("temp.tar")
tw := tar.NewWriter(tmpTar)
ps, _ := gitignore.ReadPatterns(worktree, []string{})
ignorer := gitignore.NewMatcher(ps)
fc := &FileCollector{
Fs: &memoryFs{Filesystem: fs},
Ignorer: ignorer,
SrcPath: "mygitrepo",
SrcPrefix: "mygitrepo" + string(filepath.Separator),
Handler: &TarCollector{
TarWriter: tw,
},
}
err = fc.Fs.Walk("mygitrepo", fc.CollectFiles(context.Background(), []string{}))
assert.NoError(t, err, "successfully collect files") //nolint:testifylint // pre-existing issue from nektos/act
tw.Close()
_, _ = tmpTar.Seek(0, io.SeekStart)
tr := tar.NewReader(tmpTar)
h, err := tr.Next()
files := map[string]tar.Header{}
for err == nil {
files[h.Name] = *h
h, err = tr.Next()
}
assert.Equal(t, ".env", files[".env"].Name)
assert.Equal(t, "test.env", files["test.env"].Name)
assert.Equal(t, ".env", files["test.env"].Linkname)
assert.ErrorIs(t, err, io.EOF, "tar must be read cleanly to EOF")
}
// Regression for https://gitea.com/gitea/runner/issues/876 and /941:
// re-copying an action directory must overwrite a pre-existing read-only
// file (e.g. a git pack .idx at mode 0444) instead of failing with EACCES
// on macOS or "Access is denied" on Windows.
func TestCopyCollectorWriteFileOverwritesReadOnlyFile(t *testing.T) {
dst := t.TempDir()
target := filepath.Join(dst, "sub", "pack.idx")
require.NoError(t, os.MkdirAll(filepath.Dir(target), 0o755))
require.NoError(t, os.WriteFile(target, []byte("old"), 0o444))
src := filepath.Join(t.TempDir(), "pack.idx")
require.NoError(t, os.WriteFile(src, []byte("new"), 0o444))
fi, err := os.Stat(src)
require.NoError(t, err)
cc := &CopyCollector{DstDir: dst}
require.NoError(t, cc.WriteFile("sub/pack.idx", fi, "", strings.NewReader("new")))
got, err := os.ReadFile(target)
require.NoError(t, err)
assert.Equal(t, "new", string(got))
}
// Without the destination removal, os.Symlink fails with EEXIST when the
// path already holds a regular file from an earlier copy of the action.
func TestCopyCollectorWriteFileOverwritesFileWithSymlink(t *testing.T) {
if runtime.GOOS == "windows" {
t.Skip("creating symlinks requires elevated privileges on Windows")
}
dst := t.TempDir()
target := filepath.Join(dst, "link")
require.NoError(t, os.WriteFile(target, []byte("stale"), 0o644))
fi, err := os.Lstat(target)
require.NoError(t, err)
cc := &CopyCollector{DstDir: dst}
require.NoError(t, cc.WriteFile("link", fi, "target", nil))
resolved, err := os.Readlink(target)
require.NoError(t, err)
assert.Equal(t, "target", resolved)
}