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mirror of https://github.com/veracrypt/VeraCrypt.git synced 2025-11-11 02:58:02 -06:00

Fix problems inside crash dump filter path (#1590)

* Prefer allocations to be non-executable
* Remove and reimplement DDIs inappropriately called inside HIGH_LEVEL IRQL routines
* Refactor hibernate context to be passed around in the passed FILTER_EXTENSION pointer rather than global
This commit is contained in:
Charlie
2025-09-06 03:22:50 +01:00
committed by GitHub
parent e86d83e63c
commit c1ae011ba1

View File

@@ -16,16 +16,41 @@
#include "Tests.h"
#include "cpu.h"
static DriveFilterExtension *BootDriveFilterExtension = NULL;
static LARGE_INTEGER DumpPartitionOffset;
static uint8 *WriteFilterBuffer = NULL;
static SIZE_T WriteFilterBufferSize;
typedef struct _DumpFilterContext
{
DriveFilterExtension* BootDriveFilterExtension;
LARGE_INTEGER DumpPartitionOffset;
uint8* WriteFilterBuffer;
SIZE_T WriteFilterBufferSize;
PMDL WriteFilterBufferMdl;
} DumpFilterContext;
static void Cleanup(DumpFilterContext* dumpContext)
{
if (!dumpContext)
return;
if (dumpContext->WriteFilterBufferMdl)
{
IoFreeMdl(dumpContext->WriteFilterBufferMdl);
}
if (dumpContext->WriteFilterBuffer)
{
RtlSecureZeroMemory(dumpContext->WriteFilterBuffer, dumpContext->WriteFilterBufferSize);
MmFreeContiguousMemory(dumpContext->WriteFilterBuffer);
}
RtlSecureZeroMemory(dumpContext, sizeof(DumpFilterContext));
TCfree(dumpContext);
}
NTSTATUS DumpFilterEntry (PFILTER_EXTENSION filterExtension, PFILTER_INITIALIZATION_DATA filterInitData)
{
GetSystemDriveDumpConfigRequest dumpConfig;
PHYSICAL_ADDRESS lowestAcceptableWriteBufferAddr;
PHYSICAL_ADDRESS highestAcceptableWriteBufferAddr;
PHYSICAL_ADDRESS highestAcceptableBoundaryWriteBufferAddr;
STORAGE_DEVICE_NUMBER storageDeviceNumber;
PARTITION_INFORMATION partitionInfo;
LONG version;
@@ -37,6 +62,16 @@ NTSTATUS DumpFilterEntry (PFILTER_EXTENSION filterExtension, PFILTER_INITIALIZAT
filterInitData->MinorVersion = DUMP_FILTER_MINOR_VERSION;
filterInitData->Flags |= DUMP_FILTER_CRITICAL;
DumpFilterContext* dumpContext = TCalloc ( sizeof (DumpFilterContext));
if (!dumpContext)
{
status = STATUS_INSUFFICIENT_RESOURCES;
goto err;
}
memset (dumpContext, 0, sizeof (DumpFilterContext));
// Check driver version of the main device
status = TCDeviceIoControl (NT_ROOT_PREFIX, TC_IOCTL_GET_DRIVER_VERSION, NULL, 0, &version, sizeof (version));
if (!NT_SUCCESS (status))
@@ -53,9 +88,9 @@ NTSTATUS DumpFilterEntry (PFILTER_EXTENSION filterExtension, PFILTER_INITIALIZAT
if (!NT_SUCCESS (status))
goto err;
BootDriveFilterExtension = dumpConfig.BootDriveFilterExtension;
dumpContext->BootDriveFilterExtension = dumpConfig.BootDriveFilterExtension;
if (BootDriveFilterExtension->MagicNumber != TC_BOOT_DRIVE_FILTER_EXTENSION_MAGIC_NUMBER)
if (dumpContext->BootDriveFilterExtension->MagicNumber != TC_BOOT_DRIVE_FILTER_EXTENSION_MAGIC_NUMBER)
{
status = STATUS_CRC_ERROR;
goto err;
@@ -75,13 +110,13 @@ NTSTATUS DumpFilterEntry (PFILTER_EXTENSION filterExtension, PFILTER_INITIALIZAT
if (!NT_SUCCESS (status))
goto err;
if (!BootDriveFilterExtension->SystemStorageDeviceNumberValid)
if (!dumpContext->BootDriveFilterExtension->SystemStorageDeviceNumberValid)
{
status = STATUS_INVALID_PARAMETER;
goto err;
}
if (storageDeviceNumber.DeviceNumber != BootDriveFilterExtension->SystemStorageDeviceNumber)
if (storageDeviceNumber.DeviceNumber != dumpContext->BootDriveFilterExtension->SystemStorageDeviceNumber)
{
status = STATUS_ACCESS_DENIED;
goto err;
@@ -102,10 +137,10 @@ NTSTATUS DumpFilterEntry (PFILTER_EXTENSION filterExtension, PFILTER_INITIALIZAT
partitionInfo.StartingOffset = partitionInfoEx.StartingOffset;
}
DumpPartitionOffset = partitionInfo.StartingOffset;
dumpContext->DumpPartitionOffset = partitionInfo.StartingOffset;
if (DumpPartitionOffset.QuadPart < BootDriveFilterExtension->ConfiguredEncryptedAreaStart
|| DumpPartitionOffset.QuadPart > BootDriveFilterExtension->ConfiguredEncryptedAreaEnd)
if (dumpContext->DumpPartitionOffset.QuadPart < dumpContext->BootDriveFilterExtension->ConfiguredEncryptedAreaStart
|| dumpContext->DumpPartitionOffset.QuadPart > dumpContext->BootDriveFilterExtension->ConfiguredEncryptedAreaEnd)
{
status = STATUS_ACCESS_DENIED;
goto err;
@@ -118,63 +153,78 @@ NTSTATUS DumpFilterEntry (PFILTER_EXTENSION filterExtension, PFILTER_INITIALIZAT
goto err;
}
WriteFilterBufferSize = ((SIZE_T)filterInitData->MaxPagesPerWrite) * PAGE_SIZE;
dumpContext->WriteFilterBufferSize = ((SIZE_T)filterInitData->MaxPagesPerWrite) * PAGE_SIZE;
highestAcceptableWriteBufferAddr.QuadPart = 0x7FFffffFFFFLL;
lowestAcceptableWriteBufferAddr.QuadPart = 0;
highestAcceptableWriteBufferAddr.QuadPart = -1; // QWORD_MAX
highestAcceptableBoundaryWriteBufferAddr.QuadPart = 0;
WriteFilterBuffer = MmAllocateContiguousMemory (WriteFilterBufferSize, highestAcceptableWriteBufferAddr);
if (!WriteFilterBuffer)
// Allocate resident scratch buffer as READ/WRITE only and contiguous
dumpContext->WriteFilterBuffer = MmAllocateContiguousNodeMemory (dumpContext->WriteFilterBufferSize, lowestAcceptableWriteBufferAddr, highestAcceptableWriteBufferAddr, highestAcceptableBoundaryWriteBufferAddr, PAGE_READWRITE, MM_ANY_NODE_OK);
if (!dumpContext->WriteFilterBuffer)
{
status = STATUS_INSUFFICIENT_RESOURCES;
goto err;
}
dumpContext->WriteFilterBufferMdl = IoAllocateMdl (dumpContext->WriteFilterBuffer, (ULONG)dumpContext->WriteFilterBufferSize, FALSE, FALSE, NULL);
if (!dumpContext->WriteFilterBufferMdl)
{
status = STATUS_INSUFFICIENT_RESOURCES;
goto err;
}
MmBuildMdlForNonPagedPool (dumpContext->WriteFilterBufferMdl);
filterInitData->DumpStart = DumpFilterStart;
filterInitData->DumpWrite = DumpFilterWrite;
filterInitData->DumpFinish = DumpFilterFinish;
filterInitData->DumpUnload = DumpFilterUnload;
filterInitData->DumpData = dumpContext;
Dump ("Dump filter loaded type=%d\n", filterExtension->DumpType);
return STATUS_SUCCESS;
err:
Dump ("DumpFilterEntry error %x\n", status);
Cleanup (dumpContext);
return status;
}
static NTSTATUS DumpFilterStart (PFILTER_EXTENSION filterExtension)
{
UNREFERENCED_PARAMETER(filterExtension);
Dump ("DumpFilterStart type=%d\n", filterExtension->DumpType);
if (BootDriveFilterExtension->MagicNumber != TC_BOOT_DRIVE_FILTER_EXTENSION_MAGIC_NUMBER)
DumpFilterContext* dumpContext = filterExtension->DumpData;
if (dumpContext->BootDriveFilterExtension->MagicNumber != TC_BOOT_DRIVE_FILTER_EXTENSION_MAGIC_NUMBER)
TC_BUG_CHECK (STATUS_CRC_ERROR);
return BootDriveFilterExtension->DriveMounted ? STATUS_SUCCESS : STATUS_UNSUCCESSFUL;
return dumpContext->BootDriveFilterExtension->DriveMounted ? STATUS_SUCCESS : STATUS_UNSUCCESSFUL;
}
static NTSTATUS DumpFilterWrite (PFILTER_EXTENSION filterExtension, PLARGE_INTEGER diskWriteOffset, PMDL writeMdl)
{
DumpFilterContext* dumpContext = filterExtension->DumpData;
ULONG dataLength = MmGetMdlByteCount (writeMdl);
uint64 offset = DumpPartitionOffset.QuadPart + diskWriteOffset->QuadPart;
uint64 offset = dumpContext->DumpPartitionOffset.QuadPart + diskWriteOffset->QuadPart;
uint64 intersectStart;
uint32 intersectLength;
PVOID writeBuffer;
CSHORT origMdlFlags;
UNREFERENCED_PARAMETER(filterExtension);
if (BootDriveFilterExtension->MagicNumber != TC_BOOT_DRIVE_FILTER_EXTENSION_MAGIC_NUMBER)
if (dumpContext->BootDriveFilterExtension->MagicNumber != TC_BOOT_DRIVE_FILTER_EXTENSION_MAGIC_NUMBER)
TC_BUG_CHECK (STATUS_CRC_ERROR);
if (BootDriveFilterExtension->Queue.EncryptedAreaEndUpdatePending) // Hibernation should always abort the setup thread
if (dumpContext->BootDriveFilterExtension->Queue.EncryptedAreaEndUpdatePending) // Hibernation should always abort the setup thread
TC_BUG_CHECK (STATUS_INVALID_PARAMETER);
if (BootDriveFilterExtension->Queue.EncryptedAreaStart == -1 || BootDriveFilterExtension->Queue.EncryptedAreaEnd == -1)
if (dumpContext->BootDriveFilterExtension->Queue.EncryptedAreaStart == -1 || dumpContext->BootDriveFilterExtension->Queue.EncryptedAreaEnd == -1)
return STATUS_SUCCESS;
if (dataLength > WriteFilterBufferSize)
if (dataLength > dumpContext->WriteFilterBufferSize)
TC_BUG_CHECK (STATUS_BUFFER_OVERFLOW); // Bug check is required as returning an error does not prevent data from being written to disk
if ((dataLength & (ENCRYPTION_DATA_UNIT_SIZE - 1)) != 0)
@@ -183,16 +233,19 @@ static NTSTATUS DumpFilterWrite (PFILTER_EXTENSION filterExtension, PLARGE_INTEG
if ((offset & (ENCRYPTION_DATA_UNIT_SIZE - 1)) != 0)
TC_BUG_CHECK (STATUS_INVALID_PARAMETER);
writeBuffer = MmGetSystemAddressForMdlSafe (writeMdl, (HighPagePriority | MdlMappingNoExecute));
if (!writeBuffer)
TC_BUG_CHECK (STATUS_INSUFFICIENT_RESOURCES);
// We're in trouble if the given MDL is not mapped to system address space as we're not allowed to call MmGetSystemAddressForMdlSafe() at HIGH_LEVEL IRQL.
ASSERT (writeMdl->MdlFlags & (MDL_MAPPED_TO_SYSTEM_VA | MDL_SOURCE_IS_NONPAGED_POOL));
memcpy (WriteFilterBuffer, writeBuffer, dataLength);
writeBuffer = MmGetMdlVirtualAddress (writeMdl);
if (!writeBuffer)
TC_BUG_CHECK (STATUS_INVALID_PARAMETER);
memcpy (dumpContext->WriteFilterBuffer, writeBuffer, dataLength);
GetIntersection (offset,
dataLength,
BootDriveFilterExtension->Queue.EncryptedAreaStart,
BootDriveFilterExtension->Queue.EncryptedAreaEnd,
dumpContext->BootDriveFilterExtension->Queue.EncryptedAreaStart,
dumpContext->BootDriveFilterExtension->Queue.EncryptedAreaEnd,
&intersectStart,
&intersectLength);
@@ -201,29 +254,30 @@ static NTSTATUS DumpFilterWrite (PFILTER_EXTENSION filterExtension, PLARGE_INTEG
UINT64_STRUCT dataUnit;
dataUnit.Value = intersectStart / ENCRYPTION_DATA_UNIT_SIZE;
if (BootDriveFilterExtension->Queue.RemapEncryptedArea)
if (dumpContext->BootDriveFilterExtension->Queue.RemapEncryptedArea)
{
diskWriteOffset->QuadPart += BootDriveFilterExtension->Queue.RemappedAreaOffset;
dataUnit.Value += BootDriveFilterExtension->Queue.RemappedAreaDataUnitOffset;
diskWriteOffset->QuadPart += dumpContext->BootDriveFilterExtension->Queue.RemappedAreaOffset;
dataUnit.Value += dumpContext->BootDriveFilterExtension->Queue.RemappedAreaDataUnitOffset;
}
EncryptDataUnitsCurrentThreadEx (WriteFilterBuffer + (intersectStart - offset),
EncryptDataUnitsCurrentThreadEx (dumpContext->WriteFilterBuffer + (intersectStart - offset),
&dataUnit,
intersectLength / ENCRYPTION_DATA_UNIT_SIZE,
BootDriveFilterExtension->Queue.CryptoInfo);
dumpContext->BootDriveFilterExtension->Queue.CryptoInfo);
}
origMdlFlags = writeMdl->MdlFlags;
// Replace the underlying PFN array of the write MDL to represent our encrypted buffer
PPFN_NUMBER dstPfnArray = MmGetMdlPfnArray (writeMdl);
ULONG dstPfnCount = ADDRESS_AND_SIZE_TO_SPAN_PAGES (MmGetMdlVirtualAddress (writeMdl), MmGetMdlByteCount (writeMdl));
PPFN_NUMBER srcPfnArray = MmGetMdlPfnArray (dumpContext->WriteFilterBufferMdl);
MmInitializeMdl (writeMdl, WriteFilterBuffer, dataLength);
MmBuildMdlForNonPagedPool (writeMdl);
// dstPfnCount should always be >= srcPfnCount
memcpy(dstPfnArray, srcPfnArray, dstPfnCount * sizeof(PFN_NUMBER));
// Instead of using MmGetSystemAddressForMdlSafe(), some buggy custom storage drivers may directly test MDL_MAPPED_TO_SYSTEM_VA flag,
// disregarding the fact that other MDL flags may be set by the system or a dump filter (e.g. MDL_SOURCE_IS_NONPAGED_POOL flag only).
// Therefore, to work around this issue, the original flags will be restored even if they do not match the new MDL.
// MS BitLocker also uses this hack/workaround (it should be safe to use until the MDL structure is changed).
writeMdl->MdlFlags = origMdlFlags;
writeMdl->StartVa = dumpContext->WriteFilterBufferMdl->StartVa;
writeMdl->ByteOffset = dumpContext->WriteFilterBufferMdl->ByteOffset;
writeMdl->MappedSystemVa = dumpContext->WriteFilterBufferMdl->MappedSystemVa;
return STATUS_SUCCESS;
}
@@ -240,15 +294,12 @@ static NTSTATUS DumpFilterFinish (PFILTER_EXTENSION filterExtension)
static NTSTATUS DumpFilterUnload (PFILTER_EXTENSION filterExtension)
{
UNREFERENCED_PARAMETER(filterExtension);
Dump ("DumpFilterUnload type=%d\n", filterExtension->DumpType);
if (WriteFilterBuffer)
{
memset (WriteFilterBuffer, 0, WriteFilterBufferSize);
MmFreeContiguousMemory (WriteFilterBuffer);
WriteFilterBuffer = NULL;
}
DumpFilterContext* dumpContext = filterExtension->DumpData;
Cleanup (dumpContext);
filterExtension->DumpData = NULL;
return STATUS_SUCCESS;
}
}