Fix minor issues found during code review (#41104)
src/linux/init/DnsServer.h:48 Change the data type from uint16_t to size_t to avoid a potential counter overflow on valid data. As the counter needs to hold at most 2 + 65535. src/linux/init/init.cpp:2575 Drain the pending pids on SIGCHLD. Multiple SIGCHLD will only trigger the signalfd once if not processed fast enough: https://man7.org/linux/man-pages/man7/signal.7.html src/linux/init/util.cpp:3497 Fix a wrong condition. The old logic will mask most of the errors as EINVAL. src/windows/common/WslCoreMessageQueue.h:174 Avoid a tight race condition between submit and cancel on m_tpHandle. src/windows/service/exe/LxssUserSession.cpp:897 Avoid wrong context order. The order is asserted in debug builds. The old wrong MountDisk -> CreateVm context will crash the debug service. src/windows/service/exe/WslCoreVm.cpp:1003 Fix a wrong revert logic. Where the disk will be reverted to offline if it was online. src/windows/service/exe/WslCoreVm.cpp:2755 Block more invalid mount names.
Feng Wang committed
Aug 5, 2026 at 10:42 UTC
c40ea600c4bff850ac0a16be6824f8c3436bfe69
8 files changed
+59
-24
localization/strings/en-US/Resources.resw
+1
-1
@@ -160,7 +160,7 @@ To force WSL2 to stop and detach the disk, run 'wsl.exe {}'.</value>
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<comment>"mount" is a technical term meaning to make a disk/filesystem accessible. Use the standard technical term in your locale, or keep "mount" if commonly used.</comment>
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</data>
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<data name="MessageDiskMountNameInvalid" xml:space="preserve">
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- <value>The specified mount name contains an invalid '/' character. Please retry without the invalid character.</value>
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+ <value>The mount name cannot be empty, '.', '..', or contain '/'. Please retry with a valid mount name.</value>
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<comment>"mount" is a technical term meaning to make a disk/filesystem accessible. Use the standard technical term in your locale, or keep "mount" if commonly used.</comment>
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</data>
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<data name="MessageDiskMounted" xml:space="preserve">
src/linux/init/DnsServer.h
+2
-2
@@ -44,8 +44,8 @@ private:
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wil::unique_fd m_tcpConnection;
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// Offset in m_currentDnsRequest indicating how much of the current DNS request on
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- // the TCP connection has been read. Using 2 bytes to represent the offset as the request length is represented using 2 bytes.
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- uint16_t m_currentRequestOffset = 0;
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+ // the TCP connection has been read.
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+ size_t m_currentRequestOffset = 0;
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// Buffer containing the current DNS request received on the TCP connection.
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std::vector<gsl::byte> m_currentDnsRequest;
src/linux/init/init.cpp
+21
-11
@@ -2595,23 +2595,33 @@ Return Value:
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continue;
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}
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- int Status{};
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- auto Pid = waitpid(-1, &Status, WNOHANG);
2600
- if (Pid == 0)
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- {
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- continue;
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- }
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- else if (Pid > 0)
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+ bool distroInitExited = false;
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+ for (;;)
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{
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- if (Pid == distroInitPid.value())
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+ int Status{};
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+ auto Pid = waitpid(-1, &Status, WNOHANG);
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+ if (Pid == 0)
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+ {
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+ break;
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+ }
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+ else if (Pid > 0)
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+ {
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+ distroInitExited |= (Pid == distroInitPid.value());
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+ }
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+ else if (errno == ECHILD)
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{
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- LOG_ERROR("Init has exited. Terminating distribution");
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break;
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}
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+ else
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+ {
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+ FATAL_ERROR("waitpid failed {}", errno);
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+ }
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}
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- else if (errno != ECHILD)
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+
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+ if (distroInitExited)
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{
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- FATAL_ERROR("waitpid failed {}", errno);
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+ LOG_ERROR("Init has exited. Terminating distribution");
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+ break;
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}
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}
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}
src/linux/init/util.cpp
+1
-1
@@ -3516,7 +3516,7 @@ int ProcessCreateProcessMessage(wsl::shared::Transaction& Transaction, gsl::span
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{
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execResult = 0;
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}
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- else if (execResult == sizeof(execResult))
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+ else if (ReadResult == sizeof(execResult))
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{
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// Otherwise, return the error code to the service
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execResult = abs(execResult);
src/windows/common/WslCoreMessageQueue.h
+6
-4
@@ -171,10 +171,11 @@ public:
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const auto queueLock = m_lock.lock_exclusive();
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THROW_HR_IF(HRESULT_FROM_WIN32(ERROR_CANCELLED), m_isCanceled);
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m_workItems.emplace_back(new_result);
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+
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+ // always maintain a 1:1 ratio for calls to submit_with_results() and ::SubmitThreadpoolWork
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+ SubmitThreadpoolWork(m_tpHandle.get());
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}
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- // always maintain a 1:1 ratio for calls to SubmitWorkWithResults() and ::SubmitThreadpoolWork
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- SubmitThreadpoolWork(m_tpHandle.get());
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return new_result;
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}
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catch (...)
@@ -194,10 +195,11 @@ public:
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const auto queueLock = m_lock.lock_exclusive();
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THROW_HR_IF(HRESULT_FROM_WIN32(ERROR_CANCELLED), m_isCanceled);
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m_workItems.emplace_back(std::forward<SimpleFunction_t>(functor));
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+
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+ // always maintain a 1:1 ratio for calls to submit() and ::SubmitThreadpoolWork
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+ SubmitThreadpoolWork(m_tpHandle.get());
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}
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- // always maintain a 1:1 ratio for calls to SubmitWork() and ::SubmitThreadpoolWork
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- SubmitThreadpoolWork(m_tpHandle.get());
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return true;
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}
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catch (...)
src/windows/service/exe/LxssUserSession.cpp
+1
-2
@@ -892,11 +892,10 @@ HRESULT LxssUserSessionImpl::MountDisk(
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_Out_ int* Step,
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_Out_ LPWSTR* MountName)
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{
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- ExecutionContext context(Context::MountDisk);
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-
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std::lock_guard lock(m_instanceLock);
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return wil::ResultFromException([&]() {
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_CreateVm();
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+ ExecutionContext context(Context::MountDisk);
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const auto MountDiskType = WI_IsFlagSet(Flags, LXSS_ATTACH_MOUNT_FLAGS_VHD) ? WslCoreVm::DiskType::VHD : WslCoreVm::DiskType::PassThrough;
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const auto MountResult = m_utilityVm->MountDisk(Disk, MountDiskType, PartitionIndex, Name, Type, Options);
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const auto MountNameWide = wsl::shared::string::MultiByteToWide(MountResult.MountPointName);
src/windows/service/exe/WslCoreVm.cpp
+4
-3
@@ -1000,7 +1000,7 @@ ULONG WslCoreVm::AttachDiskLockHeld(
1000
if (WI_IsFlagSet(diskFlags, DiskStateFlags::Online))
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{
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const auto diskHandle = wsl::windows::common::disk::OpenDevice(Disk, GENERIC_READ | GENERIC_WRITE, m_vmConfig.MountDeviceTimeout);
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- wsl::windows::common::disk::SetOnline(diskHandle.get(), false, m_vmConfig.MountDeviceTimeout);
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+ wsl::windows::common::disk::SetOnline(diskHandle.get(), true, m_vmConfig.MountDeviceTimeout);
1004
}
1005
});
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@@ -2742,8 +2742,9 @@ std::string WslCoreVm::s_GetMountTargetName(_In_ PCWSTR Disk, _In_opt_ PCWSTR Na
2742
if (ARGUMENT_PRESENT(Name))
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{
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auto mountName = wsl::shared::string::WideToMultiByte(Name);
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- // Throw if the name contains '/' since it is a linux path separator
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- THROW_HR_IF(WSL_E_VM_MODE_INVALID_MOUNT_NAME, mountName.find('/') != std::string::npos);
2745
+ THROW_HR_IF(
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+ WSL_E_VM_MODE_INVALID_MOUNT_NAME,
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+ mountName.empty() || mountName == "." || mountName == ".." || mountName.find('/') != std::string::npos);
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return mountName;
2749
}
2750
test/windows/MountTests.cpp
+23
@@ -341,6 +341,29 @@ class MountTests
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WaitForDiskReady();
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}
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+ WSL2_TEST_METHOD(SpecifyInvalidMountName)
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+ {
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+ SKIP_UNSUPPORTED_ARM64_MOUNT_TEST();
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+
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+ FormatDisk({L"ext4"}, true);
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+
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+ for (const auto* name : {L"\"\"", L".", L"..", L"foo/bar"})
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+ {
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+ const auto mountCommand = std::format(L"--mount {} --vhd --name {} --partition 1", VhdDevice, name);
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+ const auto [output, error] = LxsstuLaunchWslAndCaptureOutput(mountCommand, -1);
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+ VERIFY_ARE_EQUAL(
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+ output,
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+ L"The mount name cannot be empty, '.', '..', or contain '/'. Please retry with a valid mount name.\r\n"
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+ L"Error code: Wsl/Service/MountDisk/WSL_E_VM_MODE_INVALID_MOUNT_NAME\r\n",
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+ name);
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+ VERIFY_ARE_EQUAL(error, L"", name);
360
+ }
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+
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+ const auto disk = GetBlockDeviceInWsl();
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+ VERIFY_IS_TRUE(IsBlockDevicePresent(disk));
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+ VERIFY_IS_FALSE(GetBlockDeviceMount(disk + L"1").has_value());
365
+ }
366
+
367
// Test ensuring that name collision detection works in --mount --name
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WSL2_TEST_METHOD(SpecifyMountNameCollision)
369
{