fix: address review feedback on atomicWriteFile

Signed-off-by: mayanksharmaCSE <mayanksharmacse1@gmail.com>

Author: MayankSharmaCSE

pkg/unikontainers/unikontainers.go

@@ -706,7 +706,7 @@ func (u *Unikontainer) saveContainerState() error {
 	}
 
 	stateName := filepath.Join(u.BaseDir, stateFilename)
-	return atomicWriteFile(stateName, data, 0o644) //nolint: gosec
+	return atomicWriteFile(stateName, data, 0o644)
 }
 
 // getHooksByName returns the hooks for a given lifecycle stage

pkg/unikontainers/utils.go

@@ -114,7 +114,7 @@ func atomicWriteFile(path string, data []byte, perm os.FileMode) error {
 	dir := filepath.Dir(path)
 	tmpName := filepath.Join(dir, "."+filepath.Base(path)+".tmp")
 
-	f, err := os.OpenFile(tmpName, os.O_RDWR|os.O_CREATE|os.O_TRUNC|os.O_SYNC, perm)
+	f, err := os.OpenFile(tmpName, os.O_RDWR|os.O_CREATE|os.O_TRUNC, perm)
 	if err != nil {
 		return fmt.Errorf("failed to create temp file: %w", err)
 	}
@@ -136,7 +136,11 @@ func atomicWriteFile(path string, data []byte, perm os.FileMode) error {
 		return fmt.Errorf("failed to close temp file: %w", closeErr)
 	}
 
-	return os.Rename(tmpName, path)
+	if err := os.Rename(tmpName, path); err != nil {
+		os.Remove(tmpName)
+		return fmt.Errorf("failed to rename temp file to %s: %w", path, err)
+	}
+	return nil
 }
 
 // writePidFile writes the content of pid to the file defined by path

pkg/unikontainers/utils_test.go

@@ -77,6 +77,25 @@ func TestAtomicWriteFile(t *testing.T) {
 		err := atomicWriteFile(target, []byte("data"), 0o644)
 		assert.Error(t, err)
 	})
+
+	t.Run("rename failure cleans up temp file", func(t *testing.T) {
+		t.Parallel()
+		tmpDir := t.TempDir()
+
+		// Create a directory at the target path so rename fails.
+		target := filepath.Join(tmpDir, "state.json")
+		err := os.Mkdir(target, 0o755)
+		assert.NoError(t, err)
+
+		err = atomicWriteFile(target, []byte("data"), 0o644)
+		assert.Error(t, err)
+		assert.Contains(t, err.Error(), "failed to rename temp file")
+
+		// Verify the temp file was cleaned up.
+		tmpFile := filepath.Join(tmpDir, ".state.json.tmp")
+		_, err = os.Stat(tmpFile)
+		assert.True(t, os.IsNotExist(err), "Temp file should be cleaned up after rename failure")
+	})
 }
 
 func TestWritePidFile(t *testing.T) {