diff --git a/src/net/http/fs.go b/src/net/http/fs.go
index 773e74d536..2858319450 100644
--- a/src/net/http/fs.go
+++ b/src/net/http/fs.go
@@ -43,6 +43,9 @@ func mapDirOpenError(originalErr error, name string) error {
 
 	parts := strings.Split(name, string(filepath.Separator))
 	for i := range parts {
+		if parts[i] == "" {
+			continue
+		}
 		fi, err := os.Stat(strings.Join(parts[:i+1], string(filepath.Separator)))
 		if err != nil {
 			return originalErr
diff --git a/src/net/http/fs_test.go b/src/net/http/fs_test.go
index 8ff2faf9b9..1de1cd53d0 100644
--- a/src/net/http/fs_test.go
+++ b/src/net/http/fs_test.go
@@ -1176,22 +1176,33 @@ func TestFileServerNotDirError(t *testing.T) {
 		t.Errorf("StatusCode = %v; want 404", res.StatusCode)
 	}
 
-	dir := Dir("testdata")
-	_, err = dir.Open("/index.html/not-a-file")
-	if err == nil {
-		t.Fatal("err == nil; want != nil")
-	}
-	if !os.IsNotExist(err) {
-		t.Errorf("err = %v; os.IsNotExist(err) = %v; want true", err, os.IsNotExist(err))
+	test := func(name string, dir Dir) {
+		t.Run(name, func(t *testing.T) {
+			_, err = dir.Open("/index.html/not-a-file")
+			if err == nil {
+				t.Fatal("err == nil; want != nil")
+			}
+			if !os.IsNotExist(err) {
+				t.Errorf("err = %v; os.IsNotExist(err) = %v; want true", err, os.IsNotExist(err))
+			}
+
+			_, err = dir.Open("/index.html/not-a-dir/not-a-file")
+			if err == nil {
+				t.Fatal("err == nil; want != nil")
+			}
+			if !os.IsNotExist(err) {
+				t.Errorf("err = %v; os.IsNotExist(err) = %v; want true", err, os.IsNotExist(err))
+			}
+		})
 	}
 
-	_, err = dir.Open("/index.html/not-a-dir/not-a-file")
-	if err == nil {
-		t.Fatal("err == nil; want != nil")
-	}
-	if !os.IsNotExist(err) {
-		t.Errorf("err = %v; os.IsNotExist(err) = %v; want true", err, os.IsNotExist(err))
+	absPath, err := filepath.Abs("testdata")
+	if err != nil {
+		t.Fatal("get abs path:", err)
 	}
+
+	test("RelativePath", Dir("testdata"))
+	test("AbsolutePath", Dir(absPath))
 }
 
 func TestFileServerCleanPath(t *testing.T) {