https://git.reactos.org/?p=reactos.git;a=commitdiff;h=d4765fe3666e32cbf25363520e010421bd2ef307
commit d4765fe3666e32cbf25363520e010421bd2ef307
Author: Timo Kreuzer <timo.kreu...@reactos.org>
AuthorDate: Wed Dec 27 17:18:00 2017 +0100
[NTOS:MM] Implement resolving PXE/PPE page table demand zero faults
---
ntoskrnl/mm/ARM3/pagfault.c | 67 ++++++++++++++++++++++++++++++++-------------
1 file changed, 48 insertions(+), 19 deletions(-)
diff --git a/ntoskrnl/mm/ARM3/pagfault.c b/ntoskrnl/mm/ARM3/pagfault.c
index f37fa458d2..69d70cc80b 100644
--- a/ntoskrnl/mm/ARM3/pagfault.c
+++ b/ntoskrnl/mm/ARM3/pagfault.c
@@ -2025,43 +2025,67 @@ UserFault:
/* Lock the working set */
MiLockProcessWorkingSet(CurrentProcess, CurrentThread);
+ ProtectionCode = MM_INVALID_PROTECTION;
+
#if (_MI_PAGING_LEVELS == 4)
-// Note to Timo: You should call MiCheckVirtualAddress and also check if it's
zero pte
-// also this is missing the page count increment
/* Check if the PXE is valid */
if (PointerPxe->u.Hard.Valid == 0)
{
/* Right now, we only handle scenarios where the PXE is totally empty
*/
ASSERT(PointerPxe->u.Long == 0);
-#if 0
+
+ /* This is only possible for user mode addresses! */
+ ASSERT(PointerPte <= MiHighestUserPte);
+
+ /* Check if we have a VAD */
+ MiCheckVirtualAddress(Address, &ProtectionCode, &Vad);
+ if (ProtectionCode == MM_NOACCESS)
+ {
+ MiUnlockProcessWorkingSet(CurrentProcess, CurrentThread);
+ return STATUS_ACCESS_VIOLATION;
+ }
+
/* Resolve a demand zero fault */
- Status = MiResolveDemandZeroFault(PointerPpe,
- PointerPxe,
- MM_READWRITE,
- CurrentProcess,
- MM_NOIRQL);
-#endif
+ MiResolveDemandZeroFault(PointerPpe,
+ PointerPxe,
+ MM_READWRITE,
+ CurrentProcess,
+ MM_NOIRQL);
+
/* We should come back with a valid PXE */
ASSERT(PointerPxe->u.Hard.Valid == 1);
}
#endif
#if (_MI_PAGING_LEVELS >= 3)
-// Note to Timo: You should call MiCheckVirtualAddress and also check if it's
zero pte
-// also this is missing the page count increment
/* Check if the PPE is valid */
if (PointerPpe->u.Hard.Valid == 0)
{
/* Right now, we only handle scenarios where the PPE is totally empty
*/
ASSERT(PointerPpe->u.Long == 0);
-#if 0
+
+ /* This is only possible for user mode addresses! */
+ ASSERT(PointerPte <= MiHighestUserPte);
+
+ /* Check if we have a VAD, unless we did this already */
+ if (ProtectionCode == MM_INVALID_PROTECTION)
+ {
+ MiCheckVirtualAddress(Address, &ProtectionCode, &Vad);
+ }
+
+ if (ProtectionCode == MM_NOACCESS)
+ {
+ MiUnlockProcessWorkingSet(CurrentProcess, CurrentThread);
+ return STATUS_ACCESS_VIOLATION;
+ }
+
/* Resolve a demand zero fault */
- Status = MiResolveDemandZeroFault(PointerPde,
- PointerPpe,
- MM_READWRITE,
- CurrentProcess,
- MM_NOIRQL);
-#endif
+ MiResolveDemandZeroFault(PointerPde,
+ PointerPpe,
+ MM_READWRITE,
+ CurrentProcess,
+ MM_NOIRQL);
+
/* We should come back with a valid PPE */
ASSERT(PointerPpe->u.Hard.Valid == 1);
}
@@ -2077,7 +2101,12 @@ UserFault:
#if MI_TRACE_PFNS
UserPdeFault = TRUE;
#endif
- MiCheckVirtualAddress(Address, &ProtectionCode, &Vad);
+ /* Check if we have a VAD, unless we did this already */
+ if (ProtectionCode == MM_INVALID_PROTECTION)
+ {
+ MiCheckVirtualAddress(Address, &ProtectionCode, &Vad);
+ }
+
if (ProtectionCode == MM_NOACCESS)
{
#if (_MI_PAGING_LEVELS == 2)
