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Windows Driver: correctly save and restore extended processor state when performing AVX operations on Windows 7 and later. Enhance readability of code handling save/restore of floating point state.

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This commit is contained in:
Mounir IDRASSI
2017-07-04 02:05:11 +02:00
parent c2f6190627
commit 89efcdb8cd
8 changed files with 201 additions and 39 deletions
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41
src/Driver/Ntdriver.c
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@@ -73,6 +73,11 @@
#pragma alloc_text(INIT,DriverEntry)
#pragma alloc_text(INIT,TCCreateRootDeviceObject)
/* We need to silence 'type cast' warning in order to use MmGetSystemRoutineAddress.
* MmGetSystemRoutineAddress() should have been declare FARPROC instead of PVOID.
*/
#pragma warning(disable:4055)
PDRIVER_OBJECT TCDriverObject;
PDEVICE_OBJECT RootDeviceObject = NULL;
static KMUTEX RootDeviceControlMutex;
@@ -91,6 +96,8 @@ static size_t EncryptionThreadPoolFreeCpuCountLimit = 0;
static BOOL SystemFavoriteVolumeDirty = FALSE;
static BOOL PagingFileCreationPrevented = FALSE;
static BOOL EnableExtendedIoctlSupport = FALSE;
static KeSaveExtendedProcessorStateFn KeSaveExtendedProcessorStatePtr = NULL;
static KeRestoreExtendedProcessorStateFn KeRestoreExtendedProcessorStatePtr = NULL;
POOL_TYPE ExDefaultNonPagedPoolType = NonPagedPool;
ULONG ExDefaultMdlProtection = 0;
@@ -119,6 +126,15 @@ NTSTATUS DriverEntry (PDRIVER_OBJECT DriverObject, PUNICODE_STRING RegistryPath)
ExDefaultMdlProtection = MdlMappingNoExecute;
}
// KeSaveExtendedProcessorState/KeRestoreExtendedProcessorState are available starting from Windows 7
if ((OsMajorVersion > 6) || (OsMajorVersion == 6 && OsMinorVersion >= 1))
{
UNICODE_STRING funcName;
RtlInitUnicodeString(&funcName, L"KeSaveExtendedProcessorState");
KeSaveExtendedProcessorStatePtr = (KeSaveExtendedProcessorStateFn) MmGetSystemRoutineAddress(&funcName);
KeRestoreExtendedProcessorStatePtr = (KeRestoreExtendedProcessorStateFn) MmGetSystemRoutineAddress(&funcName);
}
// Load dump filter if the main driver is already loaded
if (NT_SUCCESS (TCDeviceIoControl (NT_ROOT_PREFIX, TC_IOCTL_GET_DRIVER_VERSION, NULL, 0, &version, sizeof (version))))
return DumpFilterEntry ((PFILTER_EXTENSION) DriverObject, (PFILTER_INITIALIZATION_DATA) RegistryPath);
@@ -3960,3 +3976,28 @@ BOOL IsOSAtLeast (OSVersionEnum reqMinOS)
return ((OsMajorVersion << 16 | OsMinorVersion << 8)
>= (major << 16 | minor << 8));
}
NTSTATUS NTAPI KeSaveExtendedProcessorState (
__in ULONG64 Mask,
PXSTATE_SAVE XStateSave
)
{
if (KeSaveExtendedProcessorStatePtr)
{
return (KeSaveExtendedProcessorStatePtr) (Mask, XStateSave);
}
else
{
return STATUS_SUCCESS;
}
}
VOID NTAPI KeRestoreExtendedProcessorState (
PXSTATE_SAVE XStateSave
)
{
if (KeRestoreExtendedProcessorStatePtr)
{
(KeRestoreExtendedProcessorStatePtr) (XStateSave);
}
}