From f62d7e0c24d6420604cd6d367567fa272311ce7a Mon Sep 17 00:00:00 2001
From: Pierre Schweitzer <pierre@reactos.org>
Date: Fri, 15 Sep 2017 11:49:55 +0000
Subject: [PATCH] [NTOSKRNL] Fix the way the paging IO MDLs are issued by Cc on
 read. Similar to r75834. Fixes tests from r75842.

svn path=/trunk/; revision=75844
---
 reactos/ntoskrnl/cc/copy.c | 29 ++++++++++++++++++++++-------
 1 file changed, 22 insertions(+), 7 deletions(-)

diff --git a/reactos/ntoskrnl/cc/copy.c b/reactos/ntoskrnl/cc/copy.c
index 2e2f9624464..3b0e34d7801 100644
--- a/reactos/ntoskrnl/cc/copy.c
+++ b/reactos/ntoskrnl/cc/copy.c
@@ -86,14 +86,29 @@ CcReadVirtualAddress (
         return STATUS_INSUFFICIENT_RESOURCES;
     }
 
-    MmBuildMdlForNonPagedPool(Mdl);
-    Mdl->MdlFlags |= MDL_IO_PAGE_READ;
-    KeInitializeEvent(&Event, NotificationEvent, FALSE);
-    Status = IoPageRead(Vacb->SharedCacheMap->FileObject, Mdl, &Vacb->FileOffset, &Event, &IoStatus);
-    if (Status == STATUS_PENDING)
+    Status = STATUS_SUCCESS;
+    _SEH2_TRY
     {
-        KeWaitForSingleObject(&Event, Executive, KernelMode, FALSE, NULL);
-        Status = IoStatus.Status;
+        MmProbeAndLockPages(Mdl, KernelMode, IoWriteAccess);
+    }
+    _SEH2_EXCEPT (EXCEPTION_EXECUTE_HANDLER)
+    {
+        Status = _SEH2_GetExceptionCode();
+        KeBugCheck(CACHE_MANAGER);
+    } _SEH2_END;
+
+    if (NT_SUCCESS(Status))
+    {
+        Mdl->MdlFlags |= MDL_IO_PAGE_READ;
+        KeInitializeEvent(&Event, NotificationEvent, FALSE);
+        Status = IoPageRead(Vacb->SharedCacheMap->FileObject, Mdl, &Vacb->FileOffset, &Event, &IoStatus);
+        if (Status == STATUS_PENDING)
+        {
+            KeWaitForSingleObject(&Event, Executive, KernelMode, FALSE, NULL);
+            Status = IoStatus.Status;
+        }
+
+        MmUnlockPages(Mdl);
     }
 
     IoFreeMdl(Mdl);