@samitouri / QOSAMI-WSL-2 / commits / 5106ffee

Make sure that message structures are correctly zero-initialized (#41373)

* Make sure that message structures are correctly zero-initialized Several message structures were declared without value-initialization before their fields were assigned. Use {} consistently at the declaration so the structures start out zeroed. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Drop redundant initializers from WSLC message declarations The WSLC_* message types declare a default constructor via DECLARE_MESSAGE_CTOR, so adding {} at the declaration has no effect for them. Limit the change to the aggregate message types, where {} actually initializes the structure. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> --------- Co-authored-by: Ben Hillis <benhill@ntdev.microsoft.com> Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Ben Hillis committed Aug 18, 2026 at 15:47 UTC 5106ffee8ee6015b57b9eb8f2cbdfbcbd50e2caa

7 files changed +14 -14

src/linux/init/binfmt.cpp

+2 -2

@@ -544,7 +544,7 @@ Return Value:

544 MESSAGE_HEADER Header;

545 LX_INIT_PROCESS_EXIT_STATUS ExitStatus;

546 LX_INIT_CREATE_PROCESS_RESPONSE Response;

547 - } Reply;

547 + } Reply{};

548

549 Bytes = TEMP_FAILURE_RETRY(read(PollDescriptors[0].fd, &Reply, sizeof(Reply)));

550 if (Bytes < 0)

@@ -1054,7 +1054,7 @@ Return Value:

1054 return;

1055 }

1056

1057 - LX_INIT_WINDOW_SIZE_CHANGED ResizeMessage;

1057 + LX_INIT_WINDOW_SIZE_CHANGED ResizeMessage{};

1058 ResizeMessage.Header.MessageType = LxInitMessageWindowSizeChanged;

1059 ResizeMessage.Header.MessageSize = sizeof(ResizeMessage);

1060 ResizeMessage.Columns = WindowSize.ws_col;

src/linux/init/drvfs.cpp

+1 -1

@@ -346,7 +346,7 @@ Return Value:

346 // Query the interop server for which port to use.

347 //

348

349 - MESSAGE_HEADER QueryPortMessage;

349 + MESSAGE_HEADER QueryPortMessage{};

350 QueryPortMessage.MessageType = LxInitMessageQueryDrvfsElevated;

351 QueryPortMessage.MessageSize = sizeof(QueryPortMessage);

352

src/linux/init/init.cpp

+2 -2

@@ -1238,7 +1238,7 @@ try

1238 SocketAddress.svm_port = -1;

1239 }

1240

1241 - LX_INIT_CREATE_SESSION_RESPONSE Response;

1241 + LX_INIT_CREATE_SESSION_RESPONSE Response{};

1242 Response.Header.MessageType = LxInitMessageCreateSessionResponse;

1243 Response.Header.MessageSize = sizeof(Response);

1244 Response.Port = SocketAddress.svm_port;

@@ -1378,7 +1378,7 @@ Return Value:

1378 pid_t ChildPid;

1379 wsl::shared::SocketChannel ControlChannel;

1380

1381 - LX_INIT_PROCESS_EXIT_STATUS ExitStatus;

1381 + LX_INIT_PROCESS_EXIT_STATUS ExitStatus{};

1382 unsigned int Index;

1383 bool InteropEnabled;

1384 InteropServer InteropServer;

src/linux/init/main.cpp

+1 -1

@@ -2821,7 +2821,7 @@ Return Value:

2821 --*/

2822 try

2823 {

2824 - LX_MINI_INIT_MOUNT_RESULT_MESSAGE Message;

2824 + LX_MINI_INIT_MOUNT_RESULT_MESSAGE Message{};

2825 Message.Header.MessageSize = sizeof(Message);

2826 Message.Header.MessageType = LxMiniInitMessageMountStatus;

2827 Message.Result = Result;

src/linux/init/util.cpp

+2 -2

@@ -1218,7 +1218,7 @@ Return Value:

1218 return FeatureFlags;

1219 }

1220

1221 - MESSAGE_HEADER Message;

1221 + MESSAGE_HEADER Message{};

1222 Message.MessageType = LxInitMessageQueryFeatureFlags;

1223 Message.MessageSize = sizeof(Message);

1224

@@ -1288,7 +1288,7 @@ try

1288 wsl::shared::SocketChannel channel{UtilConnectUnix(WSL_INIT_INTEROP_SOCKET), "wslinfo"};

1289 THROW_LAST_ERROR_IF(channel.Socket() < 0);

1290

1291 - MESSAGE_HEADER Message;

1291 + MESSAGE_HEADER Message{};

1292 Message.MessageType = LxInitMessageQueryNetworkingMode;

1293 Message.MessageSize = sizeof(Message);

1294

src/windows/common/interop.cpp

+2 -2

@@ -330,7 +330,7 @@ void CreateProcessVmMode(_In_ const GUID& VmId, _In_ const gsl::span<gsl::byte>&

330 if (Result.Status == 0)

331 {

332 // Process messages from the binfmt interpreter and wait for the process to exit.

333 - LX_INIT_PROCESS_EXIT_STATUS ExitStatus;

333 + LX_INIT_PROCESS_EXIT_STATUS ExitStatus{};

334 ExitStatus.Header.MessageType = LxInitMessageExitStatus;

335 ExitStatus.Header.MessageSize = sizeof(ExitStatus);

336 ExitStatus.ExitCode = ProcessInteropMessages(reinterpret_cast<HANDLE>(Sockets[3].get()), &Result);

@@ -551,7 +551,7 @@ void wsl::windows::common::interop::WorkerThread(_In_ wil::unique_handle&& Serve

551

552 // Process messages from the binfmt interpreter and wait for the

553 // process to exit.

554 - LX_INIT_PROCESS_EXIT_STATUS ExitStatus;

554 + LX_INIT_PROCESS_EXIT_STATUS ExitStatus{};

555 ExitStatus.Header.MessageType = LxInitMessageExitStatus;

556 ExitStatus.Header.MessageSize = sizeof(ExitStatus);

557 ExitStatus.ExitCode = ProcessInteropMessages(SignalPipe.first.get(), &Result);

src/windows/service/exe/WslCoreVm.cpp

+4 -4

@@ -2133,7 +2133,7 @@ WslCoreVm::MountFileAsPersistentMemory(_In_ PCWSTR FilePath, _In_ bool ReadOnly)

2133 void WslCoreVm::WaitForPmemDeviceInVm(_In_ ULONG PmemId)

2134 {

2135 // Construct the mini_init message.

2136 - LX_MINI_INIT_WAIT_FOR_PMEM_DEVICE_MESSAGE message;

2136 + LX_MINI_INIT_WAIT_FOR_PMEM_DEVICE_MESSAGE message{};

2137 message.Header.MessageType = LxMiniInitMessageWaitForPmemDevice;

2138 message.Header.MessageSize = sizeof(message);

2139 message.PmemId = PmemId;

@@ -2469,7 +2469,7 @@ void WslCoreVm::ResizeDistribution(_In_ ULONG Lun, _In_ HANDLE OutputHandle, _In

2469 {

2470 auto lock = m_lock.lock_exclusive();

2471

2472 - LX_MINI_INIT_RESIZE_DISTRIBUTION_MESSAGE message;

2472 + LX_MINI_INIT_RESIZE_DISTRIBUTION_MESSAGE message{};

2473 message.Header.MessageSize = sizeof(message);

2474 message.Header.MessageType = LxMiniInitMessageResizeDistribution;

2475 message.ScsiLun = Lun;

@@ -2494,7 +2494,7 @@ void WslCoreVm::TrimDistribution(_In_ ULONG Lun)

2494 {

2495 auto lock = m_lock.lock_exclusive();

2496

2497 - LX_MINI_INIT_TRIM_DISTRIBUTION_MESSAGE message;

2497 + LX_MINI_INIT_TRIM_DISTRIBUTION_MESSAGE message{};

2498 message.Header.MessageSize = sizeof(message);

2499 message.Header.MessageType = LxMiniInitMessageTrimDistribution;

2500 message.ScsiLun = Lun;

@@ -2566,7 +2566,7 @@ std::pair<int, LX_MINI_MOUNT_STEP> WslCoreVm::UnmountDisk(_In_ const AttachedDis

2566 }

2567

2568 // Tell the guest to flush its IO caches and stop using the disk.

2569 - LX_MINI_INIT_DETACH_MESSAGE message;

2569 + LX_MINI_INIT_DETACH_MESSAGE message{};

2570 message.Header.MessageType = LxMiniInitMessageDetach;

2571 message.Header.MessageSize = sizeof(message);

2572 message.ScsiLun = State.Lun;