Fix E_ACCESSDENIED during download if temp is hidden (#40708)
The winrt::Windows::Storage::StorageFolder::GetFolderFromPathAsync function does not accept folders with hidden or system attributes. To solve that, this PR avoids the GetFolderFromPathAsync call and opens the file stream directly.
Feng Wang committed
Jul 3, 2026 at 11:25 UTC
10a6ac3eee3bd8f109ae31de3388d85a953c4ecb
2 files changed
+104
-8
src/windows/common/wslutil.cpp
+39
-8
@@ -380,14 +380,45 @@ std::wstring wsl::windows::common::wslutil::DownloadFileImpl(
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Filename = Url.substr(lastSlash + 1);
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}
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- const auto downloadFolder =
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- winrt::Windows::Storage::StorageFolder::GetFolderFromPathAsync(std::filesystem::temp_directory_path().wstring()).get();
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-
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- const auto file =
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- downloadFolder.CreateFileAsync(Filename, winrt::Windows::Storage::CreationCollisionOption::GenerateUniqueName).get();
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- auto deleteFileOnFailure = wil::scope_exit_log(WI_DIAGNOSTICS_INFO, [&] { file.DeleteAsync().get(); });
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+ // GetFolderFromPathAsync won't work if the folder is hidden or system.
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+ auto downloadFolderPath = std::filesystem::temp_directory_path();
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+ auto filenameStem = std::filesystem::path(Filename).stem().wstring();
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+ auto filenameExtension = std::filesystem::path(Filename).extension().wstring();
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+ std::wstring filePath{};
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+ winrt::Windows::Storage::Streams::IRandomAccessStream outputStream{};
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+ for (int suffix = 1; outputStream == nullptr; suffix++)
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+ {
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+ if (suffix == 1)
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+ {
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+ filePath = (downloadFolderPath / Filename).wstring();
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+ }
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+ else
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+ {
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+ filePath = (downloadFolderPath / std::format(L"{} ({}){}", filenameStem, suffix, filenameExtension)).wstring();
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+ }
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+ try
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+ {
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+ outputStream = winrt::Windows::Storage::Streams::FileRandomAccessStream::OpenAsync(
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+ filePath,
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+ winrt::Windows::Storage::FileAccessMode::ReadWrite,
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+ winrt::Windows::Storage::StorageOpenOptions::None,
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+ winrt::Windows::Storage::Streams::FileOpenDisposition::CreateNew)
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+ .get();
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+ }
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+ catch (...)
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+ {
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+ if (wil::ResultFromCaughtException() != HRESULT_FROM_WIN32(ERROR_ALREADY_EXISTS))
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+ {
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+ throw;
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+ }
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+ }
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+ }
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- const auto outputStream = file.OpenAsync(winrt::Windows::Storage::FileAccessMode::ReadWrite).get().GetOutputStreamAt(0);
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+ auto deleteFileOnFailure = wil::scope_exit_log(WI_DIAGNOSTICS_INFO, [&] {
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+ outputStream.Close();
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+ std::error_code ec;
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+ std::filesystem::remove(filePath, ec);
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+ });
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// By default downloaded files are cached in %appdata%/local/packages/{package-family}/AC/InetCache .
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// Disable caching since there's no reason to keep local copies of .msixbundle files.
@@ -421,7 +452,7 @@ std::wstring wsl::windows::common::wslutil::DownloadFileImpl(
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download.get();
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deleteFileOnFailure.release();
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- return file.Path().c_str();
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+ return filePath;
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}
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[[nodiscard]] HANDLE wsl::windows::common::wslutil::DuplicateHandle(_In_ HANDLE Handle, _In_ std::optional<DWORD> DesiredAccess, _In_ BOOL InheritHandle)
test/windows/UnitTests.cpp
+65
@@ -7448,5 +7448,70 @@ Error code: Wsl/InstallDistro/WSL_E_INVALID_JSON\r\n",
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}
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}
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+ TEST_METHOD(DownloadToHiddenSystemTempFolder)
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+ {
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+ // Avoid contaminating the real temp folder.
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+ const auto testTempFolder = std::filesystem::temp_directory_path() / L"wsl-download-test";
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+ std::filesystem::create_directories(testTempFolder);
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+ auto cleanupTempFolder = wil::scope_exit_log(WI_DIAGNOSTICS_INFO, [&] {
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+ std::error_code error;
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+ std::filesystem::remove_all(testTempFolder, error);
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+ });
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+
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+ const auto originalAttributes = GetFileAttributesW(testTempFolder.c_str());
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+ VERIFY_IS_TRUE(originalAttributes != INVALID_FILE_ATTRIBUTES);
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+ VERIFY_IS_TRUE(SetFileAttributesW(testTempFolder.c_str(), originalAttributes | FILE_ATTRIBUTE_HIDDEN | FILE_ATTRIBUTE_SYSTEM));
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+
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+ ScopedEnvVariable temp(L"TEMP", testTempFolder.wstring());
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+ ScopedEnvVariable tmp(L"TMP", testTempFolder.wstring());
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+
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+ VERIFY_IS_TRUE(std::filesystem::equivalent(std::filesystem::temp_directory_path(), testTempFolder));
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+
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+ constexpr USHORT port = 6666;
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+ const auto endpoint = std::format(L"http://127.0.0.1:{}/", port);
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+ constexpr auto fileName = L"downloaded-file.bin";
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+ constexpr auto fileContent = L"wsl download test content";
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+ UniqueWebServer server(endpoint.c_str(), fileContent);
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+
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+ const auto url = endpoint + fileName;
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+ const auto noProgress = [](uint64_t, uint64_t) {};
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+
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+ wsl::shared::retry::RetryWithTimeout<void>(
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+ [&]() {
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+ wil::unique_socket probe{socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)};
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+ THROW_LAST_ERROR_IF(!probe);
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+
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+ sockaddr_in address{};
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+ address.sin_family = AF_INET;
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+ address.sin_port = htons(port);
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+ address.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
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+
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+ THROW_LAST_ERROR_IF(connect(probe.get(), reinterpret_cast<const sockaddr*>(&address), sizeof(address)) == SOCKET_ERROR);
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+ },
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+ std::chrono::milliseconds(500),
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+ std::chrono::seconds(5));
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+
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+ const auto firstPath = wsl::windows::common::wslutil::DownloadFileImpl(url, L"", noProgress);
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+
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+ auto readFile = [](const std::filesystem::path& Path) {
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+ std::ifstream file(Path, std::ios::binary);
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+ VERIFY_IS_TRUE(file.good());
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+ return std::string{std::istreambuf_iterator<char>(file), {}};
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+ };
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+
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+ VERIFY_ARE_EQUAL(std::filesystem::path(firstPath).parent_path(), testTempFolder);
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+ VERIFY_ARE_EQUAL(std::filesystem::path(firstPath).filename().wstring(), std::wstring(fileName));
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+ VERIFY_IS_TRUE(std::filesystem::exists(firstPath));
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+ VERIFY_ARE_EQUAL(readFile(firstPath), wsl::shared::string::WideToMultiByte(fileContent));
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+
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+ const auto secondPath = wsl::windows::common::wslutil::DownloadFileImpl(url, L"", noProgress);
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+
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+ VERIFY_ARE_EQUAL(std::filesystem::path(secondPath).parent_path(), testTempFolder);
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+ VERIFY_ARE_EQUAL(std::filesystem::path(secondPath).filename().wstring(), std::wstring(L"downloaded-file (2).bin"));
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+ VERIFY_IS_TRUE(std::filesystem::exists(firstPath));
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+ VERIFY_IS_TRUE(std::filesystem::exists(secondPath));
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+ VERIFY_ARE_EQUAL(readFile(secondPath), wsl::shared::string::WideToMultiByte(fileContent));
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+ }
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+
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}; // namespace UnitTests
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} // namespace UnitTests