From 4601776901a4db8b213d66392128a7a2f1c8d1c4 Mon Sep 17 00:00:00 2001
From: Hiroshi Ioka <hirochachacha@gmail.com>
Date: Mon, 28 Dec 2015 21:35:48 +0900
Subject: [PATCH] os: fix race condition between (*os.File).Stat and os.Chdir
 on windows

Fixes #13752

Change-Id: I53cfc4ecae90c35b6f1074f3be08489c408a6464
Reviewed-on: https://go-review.googlesource.com/18181
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
---
 src/os/os_windows_test.go | 29 +++++++++++++++++++++++++++++
 src/os/stat_windows.go    |  2 +-
 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/src/os/os_windows_test.go b/src/os/os_windows_test.go
index 66e5d42b00..3f4a01e983 100644
--- a/src/os/os_windows_test.go
+++ b/src/os/os_windows_test.go
@@ -150,3 +150,32 @@ func TestBadNetPathError(t *testing.T) {
 		t.Fatal("os.IsNotExist(syscall.Errno(53)) is false, but want true")
 	}
 }
+
+func TestStatDir(t *testing.T) {
+	defer chtmpdir(t)()
+
+	f, err := os.Open(".")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f.Close()
+
+	fi, err := f.Stat()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = os.Chdir("..")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	fi2, err := f.Stat()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !os.SameFile(fi, fi2) {
+		t.Fatal("race condition occured")
+	}
+}
diff --git a/src/os/stat_windows.go b/src/os/stat_windows.go
index 966163b2ba..0b6c22c8e8 100644
--- a/src/os/stat_windows.go
+++ b/src/os/stat_windows.go
@@ -20,7 +20,7 @@ func (file *File) Stat() (FileInfo, error) {
 	}
 	if file.isdir() {
 		// I don't know any better way to do that for directory
-		return Stat(file.name)
+		return Stat(file.dirinfo.path)
 	}
 	if file.name == DevNull {
 		return &devNullStat, nil
-- 
2.48.1