[reactos] 03/09: [NTOS:MM:X64] On x64 allocate a VAD for the shared user page

[Timo Kreuzer]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=48d1bd2c883fc3ebf143a…

commit 48d1bd2c883fc3ebf143ae905eeab07c259889b5
Author:     Timo Kreuzer <timo.kreuzer(a)reactos.org>
AuthorDate: Sat Mar 7 19:35:15 2020 +0100
Commit:     Timo Kreuzer <timo.kreuzer(a)reactos.org>
CommitDate: Sun Nov 1 09:32:27 2020 +0100

    [NTOS:MM:X64] On x64 allocate a VAD for the shared user page
---
 ntoskrnl/mm/ARM3/procsup.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)

diff --git a/ntoskrnl/mm/ARM3/procsup.c b/ntoskrnl/mm/ARM3/procsup.c
index 6407b7896d0..809f36e824d 100644
--- a/ntoskrnl/mm/ARM3/procsup.c
+++ b/ntoskrnl/mm/ARM3/procsup.c
@@ -840,6 +840,62 @@ MmCreateTeb(IN PEPROCESS Process,
     return Status;
 }
 
+#ifdef _M_AMD64
+static
+NTSTATUS
+MiInsertSharedUserPageVad(VOID)
+{
+    PMMVAD_LONG Vad;
+    ULONG_PTR BaseAddress;
+    NTSTATUS Status;
+
+    /* Allocate a VAD */
+    Vad = ExAllocatePoolWithTag(NonPagedPool, sizeof(MMVAD_LONG), 'ldaV');
+    if (Vad == NULL)
+    {
+        DPRINT1("Failed to allocate VAD for shared user page\n");
+        return STATUS_INSUFFICIENT_RESOURCES;
+    }
+
+    /* Setup the primary flags with the size, and make it private, RO */
+    Vad->u.LongFlags = 0;
+    Vad->u.VadFlags.CommitCharge = 0;
+    Vad->u.VadFlags.NoChange = TRUE;
+    Vad->u.VadFlags.VadType = VadNone;
+    Vad->u.VadFlags.MemCommit = FALSE;
+    Vad->u.VadFlags.Protection = MM_READONLY;
+    Vad->u.VadFlags.PrivateMemory = TRUE;
+    Vad->u1.Parent = NULL;
+
+    /* Setup the secondary flags to make it a secured, readonly, long VAD */
+    Vad->u2.LongFlags2 = 0;
+    Vad->u2.VadFlags2.OneSecured = TRUE;
+    Vad->u2.VadFlags2.LongVad = TRUE;
+    Vad->u2.VadFlags2.ReadOnly = FALSE;
+
+    Vad->ControlArea = NULL; // For Memory-Area hack
+    Vad->FirstPrototypePte = NULL;
+
+    /* Insert it into the process VAD table */
+    BaseAddress = MM_SHARED_USER_DATA_VA;
+    Status = MiInsertVadEx((PMMVAD)Vad,
+                            &BaseAddress,
+                            PAGE_SIZE,
+                            (ULONG_PTR)MM_HIGHEST_VAD_ADDRESS,
+                            PAGE_SIZE,
+                            MEM_TOP_DOWN);
+    if (!NT_SUCCESS(Status))
+    {
+        DPRINT1("Failed to insert shared user VAD\n");
+        ExFreePoolWithTag(Vad, 'ldaV');
+        return Status;
+    }
+
+    /* Success */
+    return STATUS_SUCCESS;
+}
+#endif
+
 VOID
 NTAPI
 MiInitializeWorkingSetList(IN PEPROCESS CurrentProcess)
@@ -957,6 +1013,16 @@ MmInitializeProcessAddressSpace(IN PEPROCESS Process,
     /* Release PFN lock */
     MiReleasePfnLock(OldIrql);
 
+#ifdef _M_AMD64
+    /* On x64 we need a VAD for the shared user page */
+    Status = MiInsertSharedUserPageVad();
+    if (!NT_SUCCESS(Status))
+    {
+        DPRINT1("MiCreateSharedUserPageVad() failed: 0x%lx\n", Status);
+        return Status;
+    }
+#endif
+
     /* Check if there's a Section Object */
     if (SectionObject)
     {