sys: IRP_MJ_CREATE

inc/winfsp/fsctl.h

@@ -133,6 +133,7 @@ typedef struct
         {
             UINT64 UserContext;         /* user context attached to an open file (unique file id) */
             UINT64 UserContext2;        /* user context attached to a kernel file object */
+                                        /*     (only low 32 bits valid in 32-bit mode) */
             UINT16 SecurityDescriptor;  /* security descriptor for existing files (offset within Buffer) */
             UINT16 SecurityDescriptorSize;  /* security descriptor size */
         } Create;

src/sys/create.c

@@ -309,11 +309,8 @@ NTSTATUS FspFsvolCreatePrepare(
 
     PDEVICE_OBJECT DeviceObject = IrpSp->DeviceObject;
     FSP_FSVOL_DEVICE_EXTENSION *FsvolDeviceExtension = FspFsvolDeviceExtension(DeviceObject);
-    ASSERT(FspFsvolDeviceExtensionKind == FsvolDeviceExtension->Base.Kind);
+    FSP_FSVRT_DEVICE_EXTENSION *FsvrtDeviceExtension =
-
+        FspFsvrtDeviceExtension(FsvolDeviceExtension->FsvrtDeviceObject);
-    /* it is not necessary to retain the FsvrtDeviceObject; our callers have already done so */
-    PDEVICE_OBJECT FsvrtDeviceObject = FsvolDeviceExtension->FsvrtDeviceObject;
-    FSP_FSVRT_DEVICE_EXTENSION *FsvrtDeviceExtension = FspFsvrtDeviceExtension(FsvrtDeviceObject);
 
     /* if the user-mode file system is not doing access checks, there is nothing else to do */
     if (!FsvrtDeviceExtension->VolumeParams.NoSystemAccessCheck)
@@ -322,14 +319,18 @@ NTSTATUS FspFsvolCreatePrepare(
         FSP_RETURN(Result = STATUS_SUCCESS);
     }
 
+    /* get a user-mode handle to the access token */
     PACCESS_STATE AccessState = IrpSp->Parameters.Create.SecurityContext->AccessState;
     HANDLE UserModeAccessToken;
-
-    /* get a user-mode handle to the access token */
     Result = ObOpenObjectByPointer(SeQuerySubjectContextToken(&AccessState->SubjectSecurityContext),
         0, 0, TOKEN_QUERY, *SeTokenObjectType, UserMode, &UserModeAccessToken);
     if (!NT_SUCCESS(Result))
+    {
+        PFILE_OBJECT FileObject = IrpSp->FileObject;
+        FspFileContextDelete(FileObject->FsContext);
+        FileObject->FsContext = 0;
         FSP_RETURN();
+    }
 
     /* send the user-mode handle to the user-mode file system */
     Irp->Tail.Overlay.DriverContext[1] = UserModeAccessToken;
@@ -343,6 +344,44 @@ VOID FspFsvolCreateComplete(
 {
     FSP_ENTER_IOC(PAGED_CODE());
 
+    PDEVICE_OBJECT DeviceObject = IrpSp->DeviceObject;
+    PFILE_OBJECT FileObject = IrpSp->FileObject;
+
+    /* if the user-mode file system sent us a failure code, fail the request now */
+    if (!NT_SUCCESS(Response->IoStatus.Status))
+    {
+        FspFileContextDelete(FileObject->FsContext);
+        FileObject->FsContext = 0;
+        goto exit;
+    }
+
+    /* record the user-mode file system contexts */
+    FSP_FILE_CONTEXT *FsContext = FileObject->FsContext;
+    BOOLEAN Inserted;
+    FsContext->UserContext = Response->Rsp.Create.UserContext;
+    FileObject->FsContext2 = (PVOID)(UINT_PTR)Response->Rsp.Create.UserContext2;
+
+    /* insert the new FsContext into our generic table */
+    FsContext = FspFsvolDeviceInsertContext(DeviceObject,
+        FsContext->UserContext, FsContext, &Inserted);
+    if (0 == FsContext)
+    {
+        FspFsvolCreateClose(Irp, Response);
+        FSP_RETURN(Result = STATUS_INSUFFICIENT_RESOURCES);
+    }
+
+    /* if it was not inserted, an FsContext with the same UserContext already exists; reuse it */
+    if (!Inserted)
+    {
+        FspFileContextDelete(FileObject->FsContext);
+        FspFileContextOpen(FsContext);
+        FileObject->FsContext = FsContext;
+    }
+
+exit:
+    Irp->IoStatus.Information = Response->IoStatus.Information;
+    Result = Response->IoStatus.Status;
+
     FSP_LEAVE_IOC(
         "FileObject=%p[%p:\"%wZ\"]",
         IrpSp->FileObject, IrpSp->FileObject->RelatedFileObject, IrpSp->FileObject->FileName);

src/sys/driver.h

@@ -262,7 +262,8 @@ PIRP FspIoqEndProcessingIrp(FSP_IOQ *Ioq, UINT_PTR IrpHint);
 NTSTATUS FspIopCreateRequest(
     PIRP Irp, PUNICODE_STRING FileName, ULONG ExtraSize, FSP_FSCTL_TRANSACT_REQ **PRequest);
 VOID FspIopCompleteRequestEx(PIRP Irp, NTSTATUS Result, BOOLEAN DeviceRelease);
-static inline VOID FspIopCompleteRequest(PIRP Irp, NTSTATUS Result)
+static inline
+VOID FspIopCompleteRequest(PIRP Irp, NTSTATUS Result)
 {
     FspIopCompleteRequestEx(Irp, Result, TRUE);
 }
@@ -363,11 +364,25 @@ typedef struct
 {
     FSRTL_ADVANCED_FCB_HEADER Header;
     FSP_FILE_CONTEXT_NONPAGED *NonPaged;
+    LONG OpenCount;
+    UINT64 UserContext;
     UNICODE_STRING FileName;
     WCHAR FileNameBuf[];
 } FSP_FILE_CONTEXT;
 NTSTATUS FspFileContextCreate(ULONG ExtraSize, FSP_FILE_CONTEXT **PContext);
 VOID FspFileContextDelete(FSP_FILE_CONTEXT *Context);
+static inline
+VOID FspFileContextOpen(FSP_FILE_CONTEXT *Context)
+{
+    InterlockedIncrement(&Context->OpenCount);
+}
+static inline
+VOID FspFileContextClose(FSP_FILE_CONTEXT *Context)
+{
+    LONG Result = InterlockedDecrement(&Context->OpenCount);
+    if (0 == Result)
+        FspFileContextDelete(Context);
+}
 
 /* misc */
 NTSTATUS FspCreateGuid(GUID *Guid);

src/sys/fileobj.c

@@ -46,6 +46,7 @@ NTSTATUS FspFileContextCreate(ULONG ExtraSize, FSP_FILE_CONTEXT **PFsContext)
     FsContext->Header.PagingIoResource = &NonPaged->PagingIoResource;
     FsRtlSetupAdvancedHeader(&FsContext->Header, &NonPaged->HeaderFastMutex);
     FsContext->NonPaged = NonPaged;
+    FsContext->OpenCount = 1;
     RtlInitEmptyUnicodeString(&FsContext->FileName, FsContext->FileNameBuf, (USHORT)ExtraSize);
 
     *PFsContext = FsContext;