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sys, dll: IRP_MJ_QUERY_INFORMATION

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This commit is contained in:
Bill Zissimopoulos
2016-01-23 23:06:22 -08:00
parent 69fd1ebd6c
commit 7b5262ccef
12 changed files with 447 additions and 11 deletions
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2
src/dll/cleanup.c
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@ -24,7 +24,7 @@ FSP_API NTSTATUS FspFileSystemSendCleanupResponse(FSP_FILE_SYSTEM *FileSystem,
memset(&Response, 0, sizeof Response);
Response.Size = sizeof Response;
Response.Kind = Request->Kind;
Response.Kind = FspFsctlTransactCleanupKind;
Response.Hint = Request->Hint;
Response.IoStatus.Status = STATUS_SUCCESS;
Response.IoStatus.Information = 0;

2
src/dll/close.c
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@ -23,7 +23,7 @@ FSP_API NTSTATUS FspFileSystemSendCloseResponse(FSP_FILE_SYSTEM *FileSystem,
memset(&Response, 0, sizeof Response);
Response.Size = sizeof Response;
Response.Kind = Request->Kind;
Response.Kind = FspFsctlTransactCloseKind;
Response.Hint = Request->Hint;
Response.IoStatus.Status = STATUS_SUCCESS;
Response.IoStatus.Information = 0;

4
src/dll/create.c
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@ -574,7 +574,7 @@ FSP_API NTSTATUS FspFileSystemSendCreateResponse(FSP_FILE_SYSTEM *FileSystem,
memset(&Response, 0, sizeof Response);
Response.Size = sizeof Response;
Response.Kind = Request->Kind;
Response.Kind = FspFsctlTransactCreateKind;
Response.Hint = Request->Hint;
Response.IoStatus.Status = STATUS_SUCCESS;
Response.IoStatus.Information = Information;
@ -592,7 +592,7 @@ FSP_API NTSTATUS FspFileSystemSendOverwriteResponse(FSP_FILE_SYSTEM *FileSystem,
memset(&Response, 0, sizeof Response);
Response.Size = sizeof Response;
Response.Kind = Request->Kind;
Response.Kind = FspFsctlTransactOverwriteKind;
Response.Hint = Request->Hint;
Response.IoStatus.Status = STATUS_SUCCESS;
Response.IoStatus.Information = 0;

39
src/dll/fileinfo.c Normal file
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@ -0,0 +1,39 @@
/**
* @file dll/close.c
*
* @copyright 2015 Bill Zissimopoulos
*/
#include <dll/library.h>
FSP_API NTSTATUS FspFileSystemOpQueryInformation(FSP_FILE_SYSTEM *FileSystem,
FSP_FSCTL_TRANSACT_REQ *Request)
{
NTSTATUS Result;
FSP_FSCTL_FILE_INFO FileInfo;
if (0 == FileSystem->Interface->GetInformation)
return FspFileSystemSendResponseWithStatus(FileSystem, Request, STATUS_INVALID_DEVICE_REQUEST);
Result = FileSystem->Interface->GetInformation(FileSystem, Request,
(PVOID)Request->Req.Close.UserContext, &FileInfo);
if (!NT_SUCCESS(Result))
return FspFileSystemSendResponseWithStatus(FileSystem, Request, Result);
return FspFileSystemSendQueryInformationResponse(FileSystem, Request, &FileInfo);
}
FSP_API NTSTATUS FspFileSystemSendQueryInformationResponse(FSP_FILE_SYSTEM *FileSystem,
FSP_FSCTL_TRANSACT_REQ *Request, const FSP_FSCTL_FILE_INFO *FileInfo)
{
FSP_FSCTL_TRANSACT_RSP Response;
memset(&Response, 0, sizeof Response);
Response.Size = sizeof Response;
Response.Kind = FspFsctlTransactCloseKind;
Response.Hint = Request->Hint;
Response.IoStatus.Status = STATUS_SUCCESS;
Response.IoStatus.Information = 0;
Response.Rsp.QueryInformation.FileInfo = *FileInfo;
return FspFileSystemSendResponse(FileSystem, &Response);
}

2
src/sys/create.c
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@ -551,6 +551,8 @@ VOID FspFsvolCreateComplete(
FileNode->Header.FileSize.QuadPart = Response->Rsp.Create.Opened.FileInfo.FileSize;
FileNode->UserContext = Response->Rsp.Create.Opened.UserContext;
FileNode->IndexNumber = Response->Rsp.Create.Opened.FileInfo.IndexNumber;
FileNode->IsDirectory = BooleanFlagOn(Response->Rsp.Create.Opened.FileInfo.FileAttributes,
FILE_ATTRIBUTE_DIRECTORY);
FileDesc->UserContext2 = Response->Rsp.Create.Opened.UserContext2;
FileDesc->State.FileInfo = Response->Rsp.Create.Opened.FileInfo;

1
src/sys/driver.h
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@ -562,6 +562,7 @@ typedef struct
PDEVICE_OBJECT FsvolDeviceObject;
UINT64 UserContext;
UINT64 IndexNumber;
BOOLEAN IsDirectory;
FSP_DEVICE_GENERIC_TABLE_ELEMENT ElementStorage;
UNICODE_STRING FileName;
WCHAR FileNameBuf[];

385
src/sys/fileinfo.c
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@ -6,16 +6,40 @@
#include <sys/driver.h>
static NTSTATUS FspFsvolQueryAllInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd, const FSP_FSCTL_FILE_INFO *FileInfo);
static NTSTATUS FspFsvolQueryAttributeTagInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd, const FSP_FSCTL_FILE_INFO *FileInfo);
static NTSTATUS FspFsvolQueryBasicInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd, const FSP_FSCTL_FILE_INFO *FileInfo);
static NTSTATUS FspFsvolQueryInternalInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd);
static NTSTATUS FspFsvolQueryNameInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd);
static NTSTATUS FspFsvolQueryNetworkOpenInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd, const FSP_FSCTL_FILE_INFO *FileInfo);
static NTSTATUS FspFsvolQueryPositionInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd);
static NTSTATUS FspFsvolQueryStandardInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd);
static NTSTATUS FspFsvolQueryInformation(
PDEVICE_OBJECT DeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp);
PDEVICE_OBJECT FsvolDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp);
FSP_IOCMPL_DISPATCH FspFsvolQueryInformationComplete;
static NTSTATUS FspFsvolSetInformation(
PDEVICE_OBJECT DeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp);
PDEVICE_OBJECT FsvolDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp);
FSP_IOCMPL_DISPATCH FspFsvolSetInformationComplete;
FSP_DRIVER_DISPATCH FspQueryInformation;
FSP_DRIVER_DISPATCH FspSetInformation;
#ifdef ALLOC_PRAGMA
#pragma alloc_text(PAGE, FspFsvolQueryAllInformation)
#pragma alloc_text(PAGE, FspFsvolQueryAttributeTagInformation)
#pragma alloc_text(PAGE, FspFsvolQueryBasicInformation)
#pragma alloc_text(PAGE, FspFsvolQueryInternalInformation)
#pragma alloc_text(PAGE, FspFsvolQueryNameInformation)
#pragma alloc_text(PAGE, FspFsvolQueryNetworkOpenInformation)
#pragma alloc_text(PAGE, FspFsvolQueryPositionInformation)
#pragma alloc_text(PAGE, FspFsvolQueryStandardInformation)
#pragma alloc_text(PAGE, FspFsvolQueryInformation)
#pragma alloc_text(PAGE, FspFsvolQueryInformationComplete)
#pragma alloc_text(PAGE, FspFsvolSetInformation)
@ -24,12 +48,319 @@ FSP_DRIVER_DISPATCH FspSetInformation;
#pragma alloc_text(PAGE, FspSetInformation)
#endif
static NTSTATUS FspFsvolQueryInformation(
PDEVICE_OBJECT DeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp)
#define GETFILEINFO() \
FSP_FSCTL_FILE_INFO FileInfoBuf; \
if (0 == FileInfo) \
{ \
if (!FspFileNodeTryGetFileInfo((FSP_FILE_NODE *)FileObject->FsContext, &FileInfoBuf))\
return FSP_STATUS_IOQ_POST; \
FileInfo = &FileInfoBuf; \
}
static NTSTATUS FspFsvolQueryAllInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd, const FSP_FSCTL_FILE_INFO *FileInfo)
{
PAGED_CODE();
return STATUS_INVALID_DEVICE_REQUEST;
if (*PBuffer + sizeof(FILE_ALL_INFORMATION) > BufferEnd)
return STATUS_BUFFER_TOO_SMALL;
PFILE_ALL_INFORMATION Info = (PFILE_ALL_INFORMATION)*PBuffer;
if (0 == FileInfo)
{
FSP_FILE_NODE *FileNode = FileObject->FsContext;
FspFileNodeAcquireShared(FileNode, Main);
*PBuffer = (PVOID)&Info->PositionInformation;
FspFsvolQueryPositionInformation(FileObject, PBuffer, BufferEnd);
*PBuffer = (PVOID)&Info->StandardInformation;
FspFsvolQueryStandardInformation(FileObject, PBuffer, BufferEnd);
FspFileNodeRelease(FileNode, Main);
Info->EaInformation.EaSize = 0;
*PBuffer = (PVOID)&Info->InternalInformation;
FspFsvolQueryInternalInformation(FileObject, PBuffer, BufferEnd);
}
GETFILEINFO();
*PBuffer = (PVOID)&Info->BasicInformation;
FspFsvolQueryBasicInformation(FileObject, PBuffer, BufferEnd, FileInfo);
*PBuffer = (PVOID)&Info->NameInformation;
return FspFsvolQueryNameInformation(FileObject, PBuffer, BufferEnd);
}
static NTSTATUS FspFsvolQueryAttributeTagInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd, const FSP_FSCTL_FILE_INFO *FileInfo)
{
PAGED_CODE();
if (*PBuffer + sizeof(FILE_ATTRIBUTE_TAG_INFORMATION) > BufferEnd)
return STATUS_BUFFER_TOO_SMALL;
GETFILEINFO();
PFILE_ATTRIBUTE_TAG_INFORMATION Info = (PFILE_ATTRIBUTE_TAG_INFORMATION)*PBuffer;
Info->FileAttributes = FileInfo->FileAttributes;
Info->ReparseTag = FileInfo->ReparseTag;
*PBuffer += sizeof(FILE_ATTRIBUTE_TAG_INFORMATION);
return STATUS_SUCCESS;
}
static NTSTATUS FspFsvolQueryBasicInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd, const FSP_FSCTL_FILE_INFO *FileInfo)
{
PAGED_CODE();
if (*PBuffer + sizeof(FILE_BASIC_INFORMATION) > BufferEnd)
return STATUS_BUFFER_TOO_SMALL;
GETFILEINFO();
PFILE_BASIC_INFORMATION Info = (PFILE_BASIC_INFORMATION)*PBuffer;
Info->CreationTime.QuadPart = FileInfo->CreationTime;
Info->LastAccessTime.QuadPart = FileInfo->LastAccessTime;
Info->LastWriteTime.QuadPart = FileInfo->LastWriteTime;
Info->ChangeTime.QuadPart = FileInfo->ChangeTime;
Info->FileAttributes = FileInfo->FileAttributes;
*PBuffer += sizeof(FILE_BASIC_INFORMATION);
return STATUS_SUCCESS;
}
static NTSTATUS FspFsvolQueryInternalInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd)
{
PAGED_CODE();
if (*PBuffer + sizeof(FILE_INTERNAL_INFORMATION) > BufferEnd)
return STATUS_BUFFER_TOO_SMALL;
FSP_FILE_NODE *FileNode = FileObject->FsContext;
PFILE_INTERNAL_INFORMATION Info = (PFILE_INTERNAL_INFORMATION)*PBuffer;
Info->IndexNumber.QuadPart = FileNode->IndexNumber;
*PBuffer += sizeof(FILE_INTERNAL_INFORMATION);
return STATUS_SUCCESS;
}
static NTSTATUS FspFsvolQueryNameInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd)
{
PAGED_CODE();
if (*PBuffer + sizeof(FILE_NAME_INFORMATION) > BufferEnd)
return STATUS_BUFFER_TOO_SMALL;
NTSTATUS Result = STATUS_SUCCESS;
FSP_FILE_NODE *FileNode = FileObject->FsContext;
FSP_FSVOL_DEVICE_EXTENSION *FsvolDeviceExtension =
FspFsvolDeviceExtension(FileNode->FsvolDeviceObject);
PFILE_NAME_INFORMATION Info = (PFILE_NAME_INFORMATION)*PBuffer;
PUINT8 Buffer = (PUINT8)Info->FileName;
ULONG CopyLength;
Info->FileNameLength = FsvolDeviceExtension->VolumePrefix.Length + FileNode->FileName.Length;
CopyLength = FsvolDeviceExtension->VolumePrefix.Length;
if (Buffer + CopyLength > BufferEnd)
{
CopyLength = (ULONG)(BufferEnd - Buffer);
Result = STATUS_BUFFER_OVERFLOW;
}
RtlCopyMemory(Buffer, FsvolDeviceExtension->VolumePrefix.Buffer, CopyLength);
Buffer += CopyLength;
CopyLength = FileNode->FileName.Length;
if (Buffer + CopyLength > BufferEnd)
{
CopyLength = (ULONG)(BufferEnd - Buffer);
Result = STATUS_BUFFER_OVERFLOW;
}
RtlCopyMemory(Buffer, FileNode->FileName.Buffer, CopyLength);
Buffer += CopyLength;
*PBuffer = Buffer;
return Result;
}
static NTSTATUS FspFsvolQueryNetworkOpenInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd, const FSP_FSCTL_FILE_INFO *FileInfo)
{
PAGED_CODE();
if (*PBuffer + sizeof(FILE_NETWORK_OPEN_INFORMATION) > BufferEnd)
return STATUS_BUFFER_TOO_SMALL;
PFILE_NETWORK_OPEN_INFORMATION Info = (PFILE_NETWORK_OPEN_INFORMATION)*PBuffer;
if (0 == FileInfo)
{
FSP_FILE_NODE *FileNode = FileObject->FsContext;
FspFileNodeAcquireShared(FileNode, Main);
Info->AllocationSize = FileNode->Header.AllocationSize;
Info->EndOfFile = FileNode->Header.FileSize;
FspFileNodeRelease(FileNode, Main);
}
GETFILEINFO();
Info->CreationTime.QuadPart = FileInfo->CreationTime;
Info->LastAccessTime.QuadPart = FileInfo->LastAccessTime;
Info->LastWriteTime.QuadPart = FileInfo->LastWriteTime;
Info->ChangeTime.QuadPart = FileInfo->ChangeTime;
Info->FileAttributes = FileInfo->FileAttributes;
*PBuffer += sizeof(FILE_BASIC_INFORMATION);
return STATUS_SUCCESS;
}
static NTSTATUS FspFsvolQueryPositionInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd)
{
PAGED_CODE();
if (*PBuffer + sizeof(FILE_POSITION_INFORMATION) > BufferEnd)
return STATUS_BUFFER_TOO_SMALL;
FSP_FILE_NODE *FileNode = FileObject->FsContext;
PFILE_POSITION_INFORMATION Info = (PFILE_POSITION_INFORMATION)*PBuffer;
FspFileNodeAcquireShared(FileNode, Main);
Info->CurrentByteOffset = FileObject->CurrentByteOffset;
FspFileNodeRelease(FileNode, Main);
*PBuffer += sizeof(FILE_POSITION_INFORMATION);
return STATUS_SUCCESS;
}
static NTSTATUS FspFsvolQueryStandardInformation(PFILE_OBJECT FileObject,
PUINT8 *PBuffer, PUINT8 BufferEnd)
{
PAGED_CODE();
if (*PBuffer + sizeof(FILE_STANDARD_INFORMATION) > BufferEnd)
return STATUS_BUFFER_TOO_SMALL;
FSP_FILE_NODE *FileNode = FileObject->FsContext;
PFILE_STANDARD_INFORMATION Info = (PFILE_STANDARD_INFORMATION)*PBuffer;
FspFileNodeAcquireShared(FileNode, Main);
Info->AllocationSize = FileNode->Header.AllocationSize;
Info->EndOfFile = FileNode->Header.FileSize;
Info->NumberOfLinks = 1;
Info->DeletePending = FileObject->DeletePending;
Info->Directory = FileNode->IsDirectory;
FspFileNodeRelease(FileNode, Main);
*PBuffer += sizeof(FILE_STANDARD_INFORMATION);
return STATUS_SUCCESS;
}
static NTSTATUS FspFsvolQueryInformation(
PDEVICE_OBJECT FsvolDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp)
{
PAGED_CODE();
/* is this a valid FileObject? */
if (!FspFileNodeIsValid(IrpSp->FileObject->FsContext))
return STATUS_INVALID_DEVICE_REQUEST;
NTSTATUS Result;
PFILE_OBJECT FileObject = IrpSp->FileObject;
PUINT8 SystemBuffer = Irp->AssociatedIrp.SystemBuffer;
PUINT8 SystemBufferEnd = (PUINT8)SystemBuffer + IrpSp->Parameters.QueryFile.Length;
switch (IrpSp->Parameters.QueryFile.FileInformationClass)
{
case FileAllInformation:
Result = FspFsvolQueryAllInformation(FileObject, &SystemBuffer, SystemBufferEnd, 0);
break;
case FileAttributeTagInformation:
Result = FspFsvolQueryAttributeTagInformation(FileObject, &SystemBuffer, SystemBufferEnd, 0);
break;
case FileBasicInformation:
Result = FspFsvolQueryBasicInformation(FileObject, &SystemBuffer, SystemBufferEnd, 0);
break;
case FileCompressionInformation:
Result = STATUS_INVALID_PARAMETER; /* no compression support */
break;
case FileEaInformation:
Result = STATUS_INVALID_PARAMETER; /* no EA support currently */
break;
case FileHardLinkInformation:
Result = STATUS_INVALID_PARAMETER; /* no hard link support */
break;
case FileInternalInformation:
Result = FspFsvolQueryInternalInformation(FileObject, &SystemBuffer, SystemBufferEnd);
break;
case FileNameInformation:
Result = FspFsvolQueryNameInformation(FileObject, &SystemBuffer, SystemBufferEnd);
break;
case FileNetworkOpenInformation:
Result = FspFsvolQueryNetworkOpenInformation(FileObject, &SystemBuffer, SystemBufferEnd, 0);
break;
case FilePositionInformation:
Result = FspFsvolQueryPositionInformation(FileObject, &SystemBuffer, SystemBufferEnd);
break;
case FileStandardInformation:
Result = FspFsvolQueryStandardInformation(FileObject, &SystemBuffer, SystemBufferEnd);
break;
case FileStreamInformation:
Result = STATUS_INVALID_PARAMETER; /* !!!: no stream support yet! */
break;
default:
Result = STATUS_INVALID_PARAMETER;
break;
}
if (FSP_STATUS_IOQ_POST != Result)
{
Irp->IoStatus.Information = (UINT_PTR)((PUINT8)SystemBufferEnd - (PUINT8)SystemBuffer);
return Result;
}
FSP_FSVOL_DEVICE_EXTENSION *FsvolDeviceExtension = FspFsvolDeviceExtension(FsvolDeviceObject);
BOOLEAN FileNameRequired = 0 != FsvolDeviceExtension->VolumeParams.FileNameRequired;
FSP_FILE_NODE *FileNode = FileObject->FsContext;
FSP_FILE_DESC *FileDesc = FileObject->FsContext2;
FSP_FSCTL_TRANSACT_REQ *Request;
ASSERT(FileNode == FileDesc->FileNode);
Result = FspIopCreateRequest(Irp, FileNameRequired ? &FileNode->FileName : 0, 0, &Request);
if (!NT_SUCCESS(Result))
return Result;
Request->Kind = FspFsctlTransactQueryInformationKind;
Request->Req.QueryInformation.UserContext = FileNode->UserContext;
Request->Req.QueryInformation.UserContext2 = FileDesc->UserContext2;
return FSP_STATUS_IOQ_POST;
}
VOID FspFsvolQueryInformationComplete(
@ -37,13 +368,55 @@ VOID FspFsvolQueryInformationComplete(
{
FSP_ENTER_IOC(PAGED_CODE());
if (!NT_SUCCESS(Response->IoStatus.Status))
{
Irp->IoStatus.Information = Response->IoStatus.Information;
Result = Response->IoStatus.Status;
FSP_RETURN();
}
PFILE_OBJECT FileObject = IrpSp->FileObject;
FSP_FILE_NODE *FileNode = FileObject->FsContext;
PUINT8 SystemBuffer = Irp->AssociatedIrp.SystemBuffer;
PUINT8 SystemBufferEnd = (PUINT8)SystemBuffer + IrpSp->Parameters.QueryFile.Length;
FspFileNodeSetFileInfo(FileNode, &Response->Rsp.QueryInformation.FileInfo);
switch (IrpSp->Parameters.QueryFile.FileInformationClass)
{
case FileAllInformation:
Result = FspFsvolQueryAllInformation(FileObject, &SystemBuffer, SystemBufferEnd,
&Response->Rsp.QueryInformation.FileInfo);
break;
case FileAttributeTagInformation:
Result = FspFsvolQueryAttributeTagInformation(FileObject, &SystemBuffer, SystemBufferEnd,
&Response->Rsp.QueryInformation.FileInfo);
break;
case FileBasicInformation:
Result = FspFsvolQueryBasicInformation(FileObject, &SystemBuffer, SystemBufferEnd,
&Response->Rsp.QueryInformation.FileInfo);
break;
case FileNetworkOpenInformation:
Result = FspFsvolQueryNetworkOpenInformation(FileObject, &SystemBuffer, SystemBufferEnd,
&Response->Rsp.QueryInformation.FileInfo);
break;
default:
ASSERT(0);
Result = STATUS_INVALID_PARAMETER;
break;
}
ASSERT(FSP_STATUS_IOQ_POST != Result);
Irp->IoStatus.Information = (UINT_PTR)((PUINT8)SystemBufferEnd - (PUINT8)SystemBuffer);
FSP_LEAVE_IOC("%s, FileObject=%p",
FileInformationClassSym(IrpSp->Parameters.QueryFile.FileInformationClass),
IrpSp->FileObject);
}
static NTSTATUS FspFsvolSetInformation(
PDEVICE_OBJECT DeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp)
PDEVICE_OBJECT FsvolDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp)
{
PAGED_CODE();

2
src/sys/iop.c
View File

@ -225,7 +225,7 @@ VOID FspIopCompleteIrpEx(PIRP Irp, NTSTATUS Result, BOOLEAN DeviceDereference)
/* get the device object out of the IRP before completion */
PDEVICE_OBJECT DeviceObject = IoGetCurrentIrpStackLocation(Irp)->DeviceObject;
if (!NT_SUCCESS(Result))
if (STATUS_SUCCESS != Result && STATUS_BUFFER_OVERFLOW != Result)
Irp->IoStatus.Information = 0;
Irp->IoStatus.Status = Result;
IoCompleteRequest(Irp, FSP_IO_INCREMENT);