From b5da069d17ab3fc2fa0382b946406fa63f52b956 Mon Sep 17 00:00:00 2001
From: Bill Zissimopoulos <billziss@navimatics.com>
Date: Wed, 23 Dec 2015 23:51:05 -0800
Subject: [PATCH] Major refactoring: testing

---
 src/sys/cleanup.c |  3 ++-
 src/sys/close.c   |  3 ++-
 src/sys/create.c  |  3 ++-
 src/sys/volume.c  | 37 +++++++++++++++++++++++++++++++++++--
 4 files changed, 41 insertions(+), 5 deletions(-)

diff --git a/src/sys/cleanup.c b/src/sys/cleanup.c
index 5cf75bb5..6e4f15a0 100644
--- a/src/sys/cleanup.c
+++ b/src/sys/cleanup.c
@@ -49,7 +49,8 @@ static NTSTATUS FspFsvolCleanup(
 {
     PAGED_CODE();
 
-    return STATUS_INVALID_DEVICE_REQUEST;
+    Irp->IoStatus.Information = 0;
+    return STATUS_SUCCESS;
 }
 
 VOID FspFsvolCleanupComplete(
diff --git a/src/sys/close.c b/src/sys/close.c
index 384534b2..30f50c58 100644
--- a/src/sys/close.c
+++ b/src/sys/close.c
@@ -46,7 +46,8 @@ static NTSTATUS FspFsvolClose(
 {
     PAGED_CODE();
 
-    return STATUS_INVALID_DEVICE_REQUEST;
+    Irp->IoStatus.Information = 0;
+    return STATUS_SUCCESS;
 }
 
 VOID FspFsvolCloseComplete(
diff --git a/src/sys/create.c b/src/sys/create.c
index 817910f8..6b8250e5 100644
--- a/src/sys/create.c
+++ b/src/sys/create.c
@@ -65,7 +65,8 @@ static NTSTATUS FspFsvolCreate(
 {
     PAGED_CODE();
 
-    return STATUS_INVALID_DEVICE_REQUEST;
+    Irp->IoStatus.Information = FILE_OPENED;
+    return STATUS_SUCCESS;
 }
 
 NTSTATUS FspFsvolCreatePrepare(
diff --git a/src/sys/volume.c b/src/sys/volume.c
index ed748a36..428d2031 100644
--- a/src/sys/volume.c
+++ b/src/sys/volume.c
@@ -8,6 +8,7 @@
 
 NTSTATUS FspVolumeCreate(
     PDEVICE_OBJECT FsctlDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp);
+static WORKER_THREAD_ROUTINE FspVolumeCreateRegisterMup;
 VOID FspVolumeDelete(
     PDEVICE_OBJECT FsctlDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp);
 static WORKER_THREAD_ROUTINE FspVolumeDeleteDelayed;
@@ -24,6 +25,7 @@ NTSTATUS FspVolumeWork(
 
 #ifdef ALLOC_PRAGMA
 #pragma alloc_text(PAGE, FspVolumeCreate)
+#pragma alloc_text(PAGE, FspVolumeCreateRegisterMup)
 #pragma alloc_text(PAGE, FspVolumeDelete)
 #pragma alloc_text(PAGE, FspVolumeDeleteDelayed)
 #pragma alloc_text(PAGE, FspVolumeMount)
@@ -36,6 +38,13 @@ NTSTATUS FspVolumeWork(
 #define PREFIXW                         L"" FSP_FSCTL_VOLUME_PARAMS_PREFIX
 #define PREFIXW_SIZE                    (sizeof PREFIXW - sizeof(WCHAR))
 
+typedef struct
+{
+    PDEVICE_OBJECT FsvolDeviceObject;
+    NTSTATUS Result;
+    FSP_SYNCHRONOUS_WORK_ITEM SynchronousWorkItem;
+} FSP_CREATE_VOLUME_REGISTER_MUP_WORK_ITEM;
+
 NTSTATUS FspVolumeCreate(
     PDEVICE_OBJECT FsctlDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp)
 {
@@ -60,6 +69,7 @@ NTSTATUS FspVolumeCreate(
     PDEVICE_OBJECT FsvolDeviceObject;
     PDEVICE_OBJECT FsvrtDeviceObject;
     FSP_FSVOL_DEVICE_EXTENSION *FsvolDeviceExtension;
+    FSP_CREATE_VOLUME_REGISTER_MUP_WORK_ITEM RegisterMupWorkItem;
 
     /* check parameters */
     if (PREFIXW_SIZE + sizeof(FSP_FSCTL_VOLUME_PARAMS) * sizeof(WCHAR) > FileObject->FileName.Length)
@@ -155,8 +165,19 @@ NTSTATUS FspVolumeCreate(
     /* do we need to register with MUP? */
     if (0 == FsvrtDeviceObject)
     {
-        Result = FsRtlRegisterUncProviderEx(&FsvolDeviceExtension->MupHandle,
-            &FsvolDeviceExtension->VolumeName, FsvolDeviceObject, 0);
+        /*
+         * Turns out we cannot call FsRtlRegisterUncProviderEx when the PreviousMode
+         * is UserMode! So we need to somehow switch to KernelMode prior to issuing
+         * the FsRtlRegisterUncProviderEx call. There seems to be no straightforward
+         * way to switch the PreviousMode (no ExSetPreviousMode). So we do it indirectly
+         * by executing a synchronous work item (FspExecuteSynchronousWorkItem).
+         */
+        RtlZeroMemory(&RegisterMupWorkItem, sizeof RegisterMupWorkItem);
+        RegisterMupWorkItem.FsvolDeviceObject = FsvolDeviceObject;
+        FspInitializeSynchronousWorkItem(&RegisterMupWorkItem.SynchronousWorkItem,
+            FspVolumeCreateRegisterMup, &RegisterMupWorkItem);
+        FspExecuteSynchronousWorkItem(&RegisterMupWorkItem.SynchronousWorkItem);
+        Result = RegisterMupWorkItem.Result;
         if (!NT_SUCCESS(Result))
         {
             FspDeviceRelease(FsvolDeviceObject);
@@ -171,6 +192,18 @@ NTSTATUS FspVolumeCreate(
     return STATUS_SUCCESS;
 }
 
+static VOID FspVolumeCreateRegisterMup(PVOID Context)
+{
+    PAGED_CODE();
+
+    FSP_CREATE_VOLUME_REGISTER_MUP_WORK_ITEM *RegisterMupWorkItem = Context;
+    PDEVICE_OBJECT FsvolDeviceObject = RegisterMupWorkItem->FsvolDeviceObject;
+    FSP_FSVOL_DEVICE_EXTENSION *FsvolDeviceExtension = FspFsvolDeviceExtension(FsvolDeviceObject);
+
+    RegisterMupWorkItem->Result = FsRtlRegisterUncProviderEx(&FsvolDeviceExtension->MupHandle,
+        &FsvolDeviceExtension->VolumeName, FsvolDeviceObject, 0);
+}
+
 VOID FspVolumeDelete(
     PDEVICE_OBJECT FsctlDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp)
 {