X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=MdeModulePkg%2FCore%2FDxe%2FMem%2FHeapGuard.c;h=9377f620c5a5f39b7298a9754e761a300ba1c326;hb=7ef91af84c04b1e5a17631bd1811c9bc1945dfdc;hp=98d597b180e6ad3b9ea8f0b18e7f15cdbee3e0ea;hpb=235a4490c8ce8b6dbac49e6ae3559cb73d6bf620;p=mirror_edk2.git
diff --git a/MdeModulePkg/Core/Dxe/Mem/HeapGuard.c b/MdeModulePkg/Core/Dxe/Mem/HeapGuard.c
index 98d597b180..9377f620c5 100644
--- a/MdeModulePkg/Core/Dxe/Mem/HeapGuard.c
+++ b/MdeModulePkg/Core/Dxe/Mem/HeapGuard.c
@@ -1,1192 +1,1747 @@
-/** @file
- UEFI Heap Guard functions.
-
-Copyright (c) 2017, Intel Corporation. All rights reserved.
-This program and the accompanying materials
-are licensed and made available under the terms and conditions of the BSD License
-which accompanies this distribution. The full text of the license may be found at
-http://opensource.org/licenses/bsd-license.php
-
-THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
-WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
-
-**/
-
-#include "DxeMain.h"
-#include "Imem.h"
-#include "HeapGuard.h"
-
-//
-// Global to avoid infinite reentrance of memory allocation when updating
-// page table attributes, which may need allocate pages for new PDE/PTE.
-//
-GLOBAL_REMOVE_IF_UNREFERENCED BOOLEAN mOnGuarding = FALSE;
-
-//
-// Pointer to table tracking the Guarded memory with bitmap, in which '1'
-// is used to indicate memory guarded. '0' might be free memory or Guard
-// page itself, depending on status of memory adjacent to it.
-//
-GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap = 0;
-
-//
-// Current depth level of map table pointed by mGuardedMemoryMap.
-// mMapLevel must be initialized at least by 1. It will be automatically
-// updated according to the address of memory just tracked.
-//
-GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel = 1;
-
-//
-// Shift and mask for each level of map table
-//
-GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH]
- = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS;
-GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH]
- = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS;
-
-/**
- Set corresponding bits in bitmap table to 1 according to the address.
-
- @param[in] Address Start address to set for.
- @param[in] BitNumber Number of bits to set.
- @param[in] BitMap Pointer to bitmap which covers the Address.
-
- @return VOID.
-**/
-STATIC
-VOID
-SetBits (
- IN EFI_PHYSICAL_ADDRESS Address,
- IN UINTN BitNumber,
- IN UINT64 *BitMap
- )
-{
- UINTN Lsbs;
- UINTN Qwords;
- UINTN Msbs;
- UINTN StartBit;
- UINTN EndBit;
-
- StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
- EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
-
- if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
- Msbs = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
- GUARDED_HEAP_MAP_ENTRY_BITS;
- Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
- Qwords = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
- } else {
- Msbs = BitNumber;
- Lsbs = 0;
- Qwords = 0;
- }
-
- if (Msbs > 0) {
- *BitMap |= LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
- BitMap += 1;
- }
-
- if (Qwords > 0) {
- SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES,
- (UINT64)-1);
- BitMap += Qwords;
- }
-
- if (Lsbs > 0) {
- *BitMap |= (LShiftU64 (1, Lsbs) - 1);
- }
-}
-
-/**
- Set corresponding bits in bitmap table to 0 according to the address.
-
- @param[in] Address Start address to set for.
- @param[in] BitNumber Number of bits to set.
- @param[in] BitMap Pointer to bitmap which covers the Address.
-
- @return VOID.
-**/
-STATIC
-VOID
-ClearBits (
- IN EFI_PHYSICAL_ADDRESS Address,
- IN UINTN BitNumber,
- IN UINT64 *BitMap
- )
-{
- UINTN Lsbs;
- UINTN Qwords;
- UINTN Msbs;
- UINTN StartBit;
- UINTN EndBit;
-
- StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
- EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
-
- if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
- Msbs = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
- GUARDED_HEAP_MAP_ENTRY_BITS;
- Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
- Qwords = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
- } else {
- Msbs = BitNumber;
- Lsbs = 0;
- Qwords = 0;
- }
-
- if (Msbs > 0) {
- *BitMap &= ~LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
- BitMap += 1;
- }
-
- if (Qwords > 0) {
- SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, 0);
- BitMap += Qwords;
- }
-
- if (Lsbs > 0) {
- *BitMap &= ~(LShiftU64 (1, Lsbs) - 1);
- }
-}
-
-/**
- Get corresponding bits in bitmap table according to the address.
-
- The value of bit 0 corresponds to the status of memory at given Address.
- No more than 64 bits can be retrieved in one call.
-
- @param[in] Address Start address to retrieve bits for.
- @param[in] BitNumber Number of bits to get.
- @param[in] BitMap Pointer to bitmap which covers the Address.
-
- @return An integer containing the bits information.
-**/
-STATIC
-UINT64
-GetBits (
- IN EFI_PHYSICAL_ADDRESS Address,
- IN UINTN BitNumber,
- IN UINT64 *BitMap
- )
-{
- UINTN StartBit;
- UINTN EndBit;
- UINTN Lsbs;
- UINTN Msbs;
- UINT64 Result;
-
- ASSERT (BitNumber <= GUARDED_HEAP_MAP_ENTRY_BITS);
-
- StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
- EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
-
- if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
- Msbs = GUARDED_HEAP_MAP_ENTRY_BITS - StartBit;
- Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
- } else {
- Msbs = BitNumber;
- Lsbs = 0;
- }
-
- Result = RShiftU64 ((*BitMap), StartBit) & (LShiftU64 (1, Msbs) - 1);
- if (Lsbs > 0) {
- BitMap += 1;
- Result |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs);
- }
-
- return Result;
-}
-
-/**
- Locate the pointer of bitmap from the guarded memory bitmap tables, which
- covers the given Address.
-
- @param[in] Address Start address to search the bitmap for.
- @param[in] AllocMapUnit Flag to indicate memory allocation for the table.
- @param[out] BitMap Pointer to bitmap which covers the Address.
-
- @return The bit number from given Address to the end of current map table.
-**/
-UINTN
-FindGuardedMemoryMap (
- IN EFI_PHYSICAL_ADDRESS Address,
- IN BOOLEAN AllocMapUnit,
- OUT UINT64 **BitMap
- )
-{
- UINTN Level;
- UINT64 *GuardMap;
- UINT64 MapMemory;
- UINTN Index;
- UINTN Size;
- UINTN BitsToUnitEnd;
- EFI_STATUS Status;
-
- //
- // Adjust current map table depth according to the address to access
- //
- while (mMapLevel < GUARDED_HEAP_MAP_TABLE_DEPTH
- &&
- RShiftU64 (
- Address,
- mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1]
- ) != 0) {
-
- if (mGuardedMemoryMap != 0) {
- Size = (mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] + 1)
- * GUARDED_HEAP_MAP_ENTRY_BYTES;
- Status = CoreInternalAllocatePages (
- AllocateAnyPages,
- EfiBootServicesData,
- EFI_SIZE_TO_PAGES (Size),
- &MapMemory,
- FALSE
- );
- ASSERT_EFI_ERROR (Status);
- ASSERT (MapMemory != 0);
-
- SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
-
- *(UINT64 *)(UINTN)MapMemory = mGuardedMemoryMap;
- mGuardedMemoryMap = MapMemory;
- }
-
- mMapLevel++;
-
- }
-
- GuardMap = &mGuardedMemoryMap;
- for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
- Level < GUARDED_HEAP_MAP_TABLE_DEPTH;
- ++Level) {
-
- if (*GuardMap == 0) {
- if (!AllocMapUnit) {
- GuardMap = NULL;
- break;
- }
-
- Size = (mLevelMask[Level] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES;
- Status = CoreInternalAllocatePages (
- AllocateAnyPages,
- EfiBootServicesData,
- EFI_SIZE_TO_PAGES (Size),
- &MapMemory,
- FALSE
- );
- ASSERT_EFI_ERROR (Status);
- ASSERT (MapMemory != 0);
-
- SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
- *GuardMap = MapMemory;
- }
-
- Index = (UINTN)RShiftU64 (Address, mLevelShift[Level]);
- Index &= mLevelMask[Level];
- GuardMap = (UINT64 *)(UINTN)((*GuardMap) + Index * sizeof (UINT64));
-
- }
-
- BitsToUnitEnd = GUARDED_HEAP_MAP_BITS - GUARDED_HEAP_MAP_BIT_INDEX (Address);
- *BitMap = GuardMap;
-
- return BitsToUnitEnd;
-}
-
-/**
- Set corresponding bits in bitmap table to 1 according to given memory range.
-
- @param[in] Address Memory address to guard from.
- @param[in] NumberOfPages Number of pages to guard.
-
- @return VOID.
-**/
-VOID
-EFIAPI
-SetGuardedMemoryBits (
- IN EFI_PHYSICAL_ADDRESS Address,
- IN UINTN NumberOfPages
- )
-{
- UINT64 *BitMap;
- UINTN Bits;
- UINTN BitsToUnitEnd;
-
- while (NumberOfPages > 0) {
- BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
- ASSERT (BitMap != NULL);
-
- if (NumberOfPages > BitsToUnitEnd) {
- // Cross map unit
- Bits = BitsToUnitEnd;
- } else {
- Bits = NumberOfPages;
- }
-
- SetBits (Address, Bits, BitMap);
-
- NumberOfPages -= Bits;
- Address += EFI_PAGES_TO_SIZE (Bits);
- }
-}
-
-/**
- Clear corresponding bits in bitmap table according to given memory range.
-
- @param[in] Address Memory address to unset from.
- @param[in] NumberOfPages Number of pages to unset guard.
-
- @return VOID.
-**/
-VOID
-EFIAPI
-ClearGuardedMemoryBits (
- IN EFI_PHYSICAL_ADDRESS Address,
- IN UINTN NumberOfPages
- )
-{
- UINT64 *BitMap;
- UINTN Bits;
- UINTN BitsToUnitEnd;
-
- while (NumberOfPages > 0) {
- BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
- ASSERT (BitMap != NULL);
-
- if (NumberOfPages > BitsToUnitEnd) {
- // Cross map unit
- Bits = BitsToUnitEnd;
- } else {
- Bits = NumberOfPages;
- }
-
- ClearBits (Address, Bits, BitMap);
-
- NumberOfPages -= Bits;
- Address += EFI_PAGES_TO_SIZE (Bits);
- }
-}
-
-/**
- Retrieve corresponding bits in bitmap table according to given memory range.
-
- @param[in] Address Memory address to retrieve from.
- @param[in] NumberOfPages Number of pages to retrieve.
-
- @return VOID.
-**/
-UINTN
-GetGuardedMemoryBits (
- IN EFI_PHYSICAL_ADDRESS Address,
- IN UINTN NumberOfPages
- )
-{
- UINT64 *BitMap;
- UINTN Bits;
- UINTN Result;
- UINTN Shift;
- UINTN BitsToUnitEnd;
-
- ASSERT (NumberOfPages <= GUARDED_HEAP_MAP_ENTRY_BITS);
-
- Result = 0;
- Shift = 0;
- while (NumberOfPages > 0) {
- BitsToUnitEnd = FindGuardedMemoryMap (Address, FALSE, &BitMap);
-
- if (NumberOfPages > BitsToUnitEnd) {
- // Cross map unit
- Bits = BitsToUnitEnd;
- } else {
- Bits = NumberOfPages;
- }
-
- if (BitMap != NULL) {
- Result |= LShiftU64 (GetBits (Address, Bits, BitMap), Shift);
- }
-
- Shift += Bits;
- NumberOfPages -= Bits;
- Address += EFI_PAGES_TO_SIZE (Bits);
- }
-
- return Result;
-}
-
-/**
- Get bit value in bitmap table for the given address.
-
- @param[in] Address The address to retrieve for.
-
- @return 1 or 0.
-**/
-UINTN
-EFIAPI
-GetGuardMapBit (
- IN EFI_PHYSICAL_ADDRESS Address
- )
-{
- UINT64 *GuardMap;
-
- FindGuardedMemoryMap (Address, FALSE, &GuardMap);
- if (GuardMap != NULL) {
- if (RShiftU64 (*GuardMap,
- GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)) & 1) {
- return 1;
- }
- }
-
- return 0;
-}
-
-/**
- Set the bit in bitmap table for the given address.
-
- @param[in] Address The address to set for.
-
- @return VOID.
-**/
-VOID
-EFIAPI
-SetGuardMapBit (
- IN EFI_PHYSICAL_ADDRESS Address
- )
-{
- UINT64 *GuardMap;
- UINT64 BitMask;
-
- FindGuardedMemoryMap (Address, TRUE, &GuardMap);
- if (GuardMap != NULL) {
- BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
- *GuardMap |= BitMask;
- }
-}
-
-/**
- Clear the bit in bitmap table for the given address.
-
- @param[in] Address The address to clear for.
-
- @return VOID.
-**/
-VOID
-EFIAPI
-ClearGuardMapBit (
- IN EFI_PHYSICAL_ADDRESS Address
- )
-{
- UINT64 *GuardMap;
- UINT64 BitMask;
-
- FindGuardedMemoryMap (Address, TRUE, &GuardMap);
- if (GuardMap != NULL) {
- BitMask = LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address));
- *GuardMap &= ~BitMask;
- }
-}
-
-/**
- Check to see if the page at the given address is a Guard page or not.
-
- @param[in] Address The address to check for.
-
- @return TRUE The page at Address is a Guard page.
- @return FALSE The page at Address is not a Guard page.
-**/
-BOOLEAN
-EFIAPI
-IsGuardPage (
- IN EFI_PHYSICAL_ADDRESS Address
- )
-{
- UINTN BitMap;
-
- BitMap = GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 3);
- return ((BitMap == 0b001) || (BitMap == 0b100) || (BitMap == 0b101));
-}
-
-/**
- Check to see if the page at the given address is a head Guard page or not.
-
- @param[in] Address The address to check for
-
- @return TRUE The page at Address is a head Guard page
- @return FALSE The page at Address is not a head Guard page
-**/
-BOOLEAN
-EFIAPI
-IsHeadGuard (
- IN EFI_PHYSICAL_ADDRESS Address
- )
-{
- return (GetGuardedMemoryBits (Address, 2) == 0b10);
-}
-
-/**
- Check to see if the page at the given address is a tail Guard page or not.
-
- @param[in] Address The address to check for.
-
- @return TRUE The page at Address is a tail Guard page.
- @return FALSE The page at Address is not a tail Guard page.
-**/
-BOOLEAN
-EFIAPI
-IsTailGuard (
- IN EFI_PHYSICAL_ADDRESS Address
- )
-{
- return (GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 2) == 0b01);
-}
-
-/**
- Check to see if the page at the given address is guarded or not.
-
- @param[in] Address The address to check for.
-
- @return TRUE The page at Address is guarded.
- @return FALSE The page at Address is not guarded.
-**/
-BOOLEAN
-EFIAPI
-IsMemoryGuarded (
- IN EFI_PHYSICAL_ADDRESS Address
- )
-{
- return (GetGuardMapBit (Address) == 1);
-}
-
-/**
- Set the page at the given address to be a Guard page.
-
- This is done by changing the page table attribute to be NOT PRSENT.
-
- @param[in] BaseAddress Page address to Guard at
-
- @return VOID
-**/
-VOID
-EFIAPI
-SetGuardPage (
- IN EFI_PHYSICAL_ADDRESS BaseAddress
- )
-{
- //
- // Set flag to make sure allocating memory without GUARD for page table
- // operation; otherwise infinite loops could be caused.
- //
- mOnGuarding = TRUE;
- //
- // Note: This might overwrite other attributes needed by other features,
- // such as memory protection (NX). Please make sure they are not enabled
- // at the same time.
- //
- gCpu->SetMemoryAttributes (gCpu, BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
- mOnGuarding = FALSE;
-}
-
-/**
- Unset the Guard page at the given address to the normal memory.
-
- This is done by changing the page table attribute to be PRSENT.
-
- @param[in] BaseAddress Page address to Guard at.
-
- @return VOID.
-**/
-VOID
-EFIAPI
-UnsetGuardPage (
- IN EFI_PHYSICAL_ADDRESS BaseAddress
- )
-{
- //
- // Set flag to make sure allocating memory without GUARD for page table
- // operation; otherwise infinite loops could be caused.
- //
- mOnGuarding = TRUE;
- //
- // Note: This might overwrite other attributes needed by other features,
- // such as memory protection (NX). Please make sure they are not enabled
- // at the same time.
- //
- gCpu->SetMemoryAttributes (gCpu, BaseAddress, EFI_PAGE_SIZE, 0);
- mOnGuarding = FALSE;
-}
-
-/**
- Check to see if the memory at the given address should be guarded or not.
-
- @param[in] MemoryType Memory type to check.
- @param[in] AllocateType Allocation type to check.
- @param[in] PageOrPool Indicate a page allocation or pool allocation.
-
-
- @return TRUE The given type of memory should be guarded.
- @return FALSE The given type of memory should not be guarded.
-**/
-BOOLEAN
-IsMemoryTypeToGuard (
- IN EFI_MEMORY_TYPE MemoryType,
- IN EFI_ALLOCATE_TYPE AllocateType,
- IN UINT8 PageOrPool
- )
-{
- UINT64 TestBit;
- UINT64 ConfigBit;
- BOOLEAN InSmm;
-
- if (gCpu == NULL || AllocateType == AllocateAddress) {
- return FALSE;
- }
-
- InSmm = FALSE;
- if (gSmmBase2 != NULL) {
- gSmmBase2->InSmm (gSmmBase2, &InSmm);
- }
-
- if (InSmm) {
- return FALSE;
- }
-
- if ((PcdGet8 (PcdHeapGuardPropertyMask) & PageOrPool) == 0) {
- return FALSE;
- }
-
- if (PageOrPool == GUARD_HEAP_TYPE_POOL) {
- ConfigBit = PcdGet64 (PcdHeapGuardPoolType);
- } else if (PageOrPool == GUARD_HEAP_TYPE_PAGE) {
- ConfigBit = PcdGet64 (PcdHeapGuardPageType);
- } else {
- ConfigBit = (UINT64)-1;
- }
-
- if ((UINT32)MemoryType >= MEMORY_TYPE_OS_RESERVED_MIN) {
- TestBit = BIT63;
- } else if ((UINT32) MemoryType >= MEMORY_TYPE_OEM_RESERVED_MIN) {
- TestBit = BIT62;
- } else if (MemoryType < EfiMaxMemoryType) {
- TestBit = LShiftU64 (1, MemoryType);
- } else if (MemoryType == EfiMaxMemoryType) {
- TestBit = (UINT64)-1;
- } else {
- TestBit = 0;
- }
-
- return ((ConfigBit & TestBit) != 0);
-}
-
-/**
- Check to see if the pool at the given address should be guarded or not.
-
- @param[in] MemoryType Pool type to check.
-
-
- @return TRUE The given type of pool should be guarded.
- @return FALSE The given type of pool should not be guarded.
-**/
-BOOLEAN
-IsPoolTypeToGuard (
- IN EFI_MEMORY_TYPE MemoryType
- )
-{
- return IsMemoryTypeToGuard (MemoryType, AllocateAnyPages,
- GUARD_HEAP_TYPE_POOL);
-}
-
-/**
- Check to see if the page at the given address should be guarded or not.
-
- @param[in] MemoryType Page type to check.
- @param[in] AllocateType Allocation type to check.
-
- @return TRUE The given type of page should be guarded.
- @return FALSE The given type of page should not be guarded.
-**/
-BOOLEAN
-IsPageTypeToGuard (
- IN EFI_MEMORY_TYPE MemoryType,
- IN EFI_ALLOCATE_TYPE AllocateType
- )
-{
- return IsMemoryTypeToGuard (MemoryType, AllocateType, GUARD_HEAP_TYPE_PAGE);
-}
-
-/**
- Set head Guard and tail Guard for the given memory range.
-
- @param[in] Memory Base address of memory to set guard for.
- @param[in] NumberOfPages Memory size in pages.
-
- @return VOID
-**/
-VOID
-SetGuardForMemory (
- IN EFI_PHYSICAL_ADDRESS Memory,
- IN UINTN NumberOfPages
- )
-{
- EFI_PHYSICAL_ADDRESS GuardPage;
-
- //
- // Set tail Guard
- //
- GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
- if (!IsGuardPage (GuardPage)) {
- SetGuardPage (GuardPage);
- }
-
- // Set head Guard
- GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
- if (!IsGuardPage (GuardPage)) {
- SetGuardPage (GuardPage);
- }
-
- //
- // Mark the memory range as Guarded
- //
- SetGuardedMemoryBits (Memory, NumberOfPages);
-}
-
-/**
- Unset head Guard and tail Guard for the given memory range.
-
- @param[in] Memory Base address of memory to unset guard for.
- @param[in] NumberOfPages Memory size in pages.
-
- @return VOID
-**/
-VOID
-UnsetGuardForMemory (
- IN EFI_PHYSICAL_ADDRESS Memory,
- IN UINTN NumberOfPages
- )
-{
- EFI_PHYSICAL_ADDRESS GuardPage;
-
- if (NumberOfPages == 0) {
- return;
- }
-
- //
- // Head Guard must be one page before, if any.
- //
- GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
- if (IsHeadGuard (GuardPage)) {
- if (!IsMemoryGuarded (GuardPage - EFI_PAGES_TO_SIZE (1))) {
- //
- // If the head Guard is not a tail Guard of adjacent memory block,
- // unset it.
- //
- UnsetGuardPage (GuardPage);
- }
- } else if (IsMemoryGuarded (GuardPage)) {
- //
- // Pages before memory to free are still in Guard. It's a partial free
- // case. Turn first page of memory block to free into a new Guard.
- //
- SetGuardPage (Memory);
- }
-
- //
- // Tail Guard must be the page after this memory block to free, if any.
- //
- GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
- if (IsTailGuard (GuardPage)) {
- if (!IsMemoryGuarded (GuardPage + EFI_PAGES_TO_SIZE (1))) {
- //
- // If the tail Guard is not a head Guard of adjacent memory block,
- // free it; otherwise, keep it.
- //
- UnsetGuardPage (GuardPage);
- }
- } else if (IsMemoryGuarded (GuardPage)) {
- //
- // Pages after memory to free are still in Guard. It's a partial free
- // case. We need to keep one page to be a head Guard.
- //
- SetGuardPage (GuardPage - EFI_PAGES_TO_SIZE (1));
- }
-
- //
- // No matter what, we just clear the mark of the Guarded memory.
- //
- ClearGuardedMemoryBits(Memory, NumberOfPages);
-}
-
-/**
- Adjust address of free memory according to existing and/or required Guard.
-
- This function will check if there're existing Guard pages of adjacent
- memory blocks, and try to use it as the Guard page of the memory to be
- allocated.
-
- @param[in] Start Start address of free memory block.
- @param[in] Size Size of free memory block.
- @param[in] SizeRequested Size of memory to allocate.
-
- @return The end address of memory block found.
- @return 0 if no enough space for the required size of memory and its Guard.
-**/
-UINT64
-AdjustMemoryS (
- IN UINT64 Start,
- IN UINT64 Size,
- IN UINT64 SizeRequested
- )
-{
- UINT64 Target;
-
- Target = Start + Size - SizeRequested;
-
- //
- // At least one more page needed for Guard page.
- //
- if (Size < (SizeRequested + EFI_PAGES_TO_SIZE (1))) {
- return 0;
- }
-
- if (!IsGuardPage (Start + Size)) {
- // No Guard at tail to share. One more page is needed.
- Target -= EFI_PAGES_TO_SIZE (1);
- }
-
- // Out of range?
- if (Target < Start) {
- return 0;
- }
-
- // At the edge?
- if (Target == Start) {
- if (!IsGuardPage (Target - EFI_PAGES_TO_SIZE (1))) {
- // No enough space for a new head Guard if no Guard at head to share.
- return 0;
- }
- }
-
- // OK, we have enough pages for memory and its Guards. Return the End of the
- // free space.
- return Target + SizeRequested - 1;
-}
-
-/**
- Adjust the start address and number of pages to free according to Guard.
-
- The purpose of this function is to keep the shared Guard page with adjacent
- memory block if it's still in guard, or free it if no more sharing. Another
- is to reserve pages as Guard pages in partial page free situation.
-
- @param[in,out] Memory Base address of memory to free.
- @param[in,out] NumberOfPages Size of memory to free.
-
- @return VOID.
-**/
-VOID
-AdjustMemoryF (
- IN OUT EFI_PHYSICAL_ADDRESS *Memory,
- IN OUT UINTN *NumberOfPages
- )
-{
- EFI_PHYSICAL_ADDRESS Start;
- EFI_PHYSICAL_ADDRESS MemoryToTest;
- UINTN PagesToFree;
-
- if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) {
- return;
- }
-
- Start = *Memory;
- PagesToFree = *NumberOfPages;
-
- //
- // Head Guard must be one page before, if any.
- //
- MemoryToTest = Start - EFI_PAGES_TO_SIZE (1);
- if (IsHeadGuard (MemoryToTest)) {
- if (!IsMemoryGuarded (MemoryToTest - EFI_PAGES_TO_SIZE (1))) {
- //
- // If the head Guard is not a tail Guard of adjacent memory block,
- // free it; otherwise, keep it.
- //
- Start -= EFI_PAGES_TO_SIZE (1);
- PagesToFree += 1;
- }
- } else if (IsMemoryGuarded (MemoryToTest)) {
- //
- // Pages before memory to free are still in Guard. It's a partial free
- // case. We need to keep one page to be a tail Guard.
- //
- Start += EFI_PAGES_TO_SIZE (1);
- PagesToFree -= 1;
- }
-
- //
- // Tail Guard must be the page after this memory block to free, if any.
- //
- MemoryToTest = Start + EFI_PAGES_TO_SIZE (PagesToFree);
- if (IsTailGuard (MemoryToTest)) {
- if (!IsMemoryGuarded (MemoryToTest + EFI_PAGES_TO_SIZE (1))) {
- //
- // If the tail Guard is not a head Guard of adjacent memory block,
- // free it; otherwise, keep it.
- //
- PagesToFree += 1;
- }
- } else if (IsMemoryGuarded (MemoryToTest)) {
- //
- // Pages after memory to free are still in Guard. It's a partial free
- // case. We need to keep one page to be a head Guard.
- //
- PagesToFree -= 1;
- }
-
- *Memory = Start;
- *NumberOfPages = PagesToFree;
-}
-
-/**
- Adjust the base and number of pages to really allocate according to Guard.
-
- @param[in,out] Memory Base address of free memory.
- @param[in,out] NumberOfPages Size of memory to allocate.
-
- @return VOID.
-**/
-VOID
-AdjustMemoryA (
- IN OUT EFI_PHYSICAL_ADDRESS *Memory,
- IN OUT UINTN *NumberOfPages
- )
-{
- //
- // FindFreePages() has already taken the Guard into account. It's safe to
- // adjust the start address and/or number of pages here, to make sure that
- // the Guards are also "allocated".
- //
- if (!IsGuardPage (*Memory + EFI_PAGES_TO_SIZE (*NumberOfPages))) {
- // No tail Guard, add one.
- *NumberOfPages += 1;
- }
-
- if (!IsGuardPage (*Memory - EFI_PAGE_SIZE)) {
- // No head Guard, add one.
- *Memory -= EFI_PAGE_SIZE;
- *NumberOfPages += 1;
- }
-}
-
-/**
- Adjust the pool head position to make sure the Guard page is adjavent to
- pool tail or pool head.
-
- @param[in] Memory Base address of memory allocated.
- @param[in] NoPages Number of pages actually allocated.
- @param[in] Size Size of memory requested.
- (plus pool head/tail overhead)
-
- @return Address of pool head.
-**/
-VOID *
-AdjustPoolHeadA (
- IN EFI_PHYSICAL_ADDRESS Memory,
- IN UINTN NoPages,
- IN UINTN Size
- )
-{
- if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
- //
- // Pool head is put near the head Guard
- //
- return (VOID *)(UINTN)Memory;
- }
-
- //
- // Pool head is put near the tail Guard
- //
- return (VOID *)(UINTN)(Memory + EFI_PAGES_TO_SIZE (NoPages) - Size);
-}
-
-/**
- Get the page base address according to pool head address.
-
- @param[in] Memory Head address of pool to free.
-
- @return Address of pool head.
-**/
-VOID *
-AdjustPoolHeadF (
- IN EFI_PHYSICAL_ADDRESS Memory
- )
-{
- if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0) {
- //
- // Pool head is put near the head Guard
- //
- return (VOID *)(UINTN)Memory;
- }
-
- //
- // Pool head is put near the tail Guard
- //
- return (VOID *)(UINTN)(Memory & ~EFI_PAGE_MASK);
-}
-
-/**
- Allocate or free guarded memory.
-
- @param[in] Start Start address of memory to allocate or free.
- @param[in] NumberOfPages Memory size in pages.
- @param[in] NewType Memory type to convert to.
-
- @return VOID.
-**/
-EFI_STATUS
-CoreConvertPagesWithGuard (
- IN UINT64 Start,
- IN UINTN NumberOfPages,
- IN EFI_MEMORY_TYPE NewType
- )
-{
- if (NewType == EfiConventionalMemory) {
- AdjustMemoryF (&Start, &NumberOfPages);
- } else {
- AdjustMemoryA (&Start, &NumberOfPages);
- }
-
- return CoreConvertPages(Start, NumberOfPages, NewType);
-}
-
-/**
- Helper function to convert a UINT64 value in binary to a string.
-
- @param[in] Value Value of a UINT64 integer.
- @param[out] BinString String buffer to contain the conversion result.
-
- @return VOID.
-**/
-VOID
-Uint64ToBinString (
- IN UINT64 Value,
- OUT CHAR8 *BinString
- )
-{
- UINTN Index;
-
- if (BinString == NULL) {
- return;
- }
-
- for (Index = 64; Index > 0; --Index) {
- BinString[Index - 1] = '0' + (Value & 1);
- Value = RShiftU64 (Value, 1);
- }
- BinString[64] = '\0';
-}
-
-/**
- Dump the guarded memory bit map.
-**/
-VOID
-EFIAPI
-DumpGuardedMemoryBitmap (
- VOID
- )
-{
- UINTN Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
- UINTN Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
- UINTN Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
- UINT64 Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
- UINT64 Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
- UINT64 TableEntry;
- UINT64 Address;
- INTN Level;
- UINTN RepeatZero;
- CHAR8 String[GUARDED_HEAP_MAP_ENTRY_BITS + 1];
- CHAR8 *Ruler1;
- CHAR8 *Ruler2;
-
- if (mGuardedMemoryMap == 0) {
- return;
- }
-
- Ruler1 = " 3 2 1 0";
- Ruler2 = "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210";
-
- DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "============================="
- " Guarded Memory Bitmap "
- "==============================\r\n"));
- DEBUG ((HEAP_GUARD_DEBUG_LEVEL, " %a\r\n", Ruler1));
- DEBUG ((HEAP_GUARD_DEBUG_LEVEL, " %a\r\n", Ruler2));
-
- CopyMem (Entries, mLevelMask, sizeof (Entries));
- CopyMem (Shifts, mLevelShift, sizeof (Shifts));
-
- SetMem (Indices, sizeof(Indices), 0);
- SetMem (Tables, sizeof(Tables), 0);
- SetMem (Addresses, sizeof(Addresses), 0);
-
- Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
- Tables[Level] = mGuardedMemoryMap;
- Address = 0;
- RepeatZero = 0;
-
- while (TRUE) {
- if (Indices[Level] > Entries[Level]) {
-
- Tables[Level] = 0;
- Level -= 1;
- RepeatZero = 0;
-
- DEBUG ((
- HEAP_GUARD_DEBUG_LEVEL,
- "========================================="
- "=========================================\r\n"
- ));
-
- } else {
-
- TableEntry = ((UINT64 *)(UINTN)Tables[Level])[Indices[Level]];
- Address = Addresses[Level];
-
- if (TableEntry == 0) {
-
- if (Level == GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
- if (RepeatZero == 0) {
- Uint64ToBinString(TableEntry, String);
- DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
- } else if (RepeatZero == 1) {
- DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "... : ...\r\n"));
- }
- RepeatZero += 1;
- }
-
- } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
-
- Level += 1;
- Tables[Level] = TableEntry;
- Addresses[Level] = Address;
- Indices[Level] = 0;
- RepeatZero = 0;
-
- continue;
-
- } else {
-
- RepeatZero = 0;
- Uint64ToBinString(TableEntry, String);
- DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
-
- }
- }
-
- if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
- break;
- }
-
- Indices[Level] += 1;
- Address = (Level == 0) ? 0 : Addresses[Level - 1];
- Addresses[Level] = Address | LShiftU64(Indices[Level], Shifts[Level]);
-
- }
-}
-
+/** @file
+ UEFI Heap Guard functions.
+
+Copyright (c) 2017-2018, Intel Corporation. All rights reserved.
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include "DxeMain.h"
+#include "Imem.h"
+#include "HeapGuard.h"
+
+//
+// Global to avoid infinite reentrance of memory allocation when updating
+// page table attributes, which may need allocate pages for new PDE/PTE.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED BOOLEAN mOnGuarding = FALSE;
+
+//
+// Pointer to table tracking the Guarded memory with bitmap, in which '1'
+// is used to indicate memory guarded. '0' might be free memory or Guard
+// page itself, depending on status of memory adjacent to it.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap = 0;
+
+//
+// Current depth level of map table pointed by mGuardedMemoryMap.
+// mMapLevel must be initialized at least by 1. It will be automatically
+// updated according to the address of memory just tracked.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel = 1;
+
+//
+// Shift and mask for each level of map table
+//
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH]
+ = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS;
+GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH]
+ = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS;
+
+//
+// Used for promoting freed but not used pages.
+//
+GLOBAL_REMOVE_IF_UNREFERENCED EFI_PHYSICAL_ADDRESS mLastPromotedPage = BASE_4GB;
+
+/**
+ Set corresponding bits in bitmap table to 1 according to the address.
+
+ @param[in] Address Start address to set for.
+ @param[in] BitNumber Number of bits to set.
+ @param[in] BitMap Pointer to bitmap which covers the Address.
+
+ @return VOID.
+**/
+STATIC
+VOID
+SetBits (
+ IN EFI_PHYSICAL_ADDRESS Address,
+ IN UINTN BitNumber,
+ IN UINT64 *BitMap
+ )
+{
+ UINTN Lsbs;
+ UINTN Qwords;
+ UINTN Msbs;
+ UINTN StartBit;
+ UINTN EndBit;
+
+ StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+ EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+ if ((StartBit + BitNumber) >= GUARDED_HEAP_MAP_ENTRY_BITS) {
+ Msbs = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+ GUARDED_HEAP_MAP_ENTRY_BITS;
+ Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+ Qwords = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+ } else {
+ Msbs = BitNumber;
+ Lsbs = 0;
+ Qwords = 0;
+ }
+
+ if (Msbs > 0) {
+ *BitMap |= LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+ BitMap += 1;
+ }
+
+ if (Qwords > 0) {
+ SetMem64 (
+ (VOID *)BitMap,
+ Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES,
+ (UINT64)-1
+ );
+ BitMap += Qwords;
+ }
+
+ if (Lsbs > 0) {
+ *BitMap |= (LShiftU64 (1, Lsbs) - 1);
+ }
+}
+
+/**
+ Set corresponding bits in bitmap table to 0 according to the address.
+
+ @param[in] Address Start address to set for.
+ @param[in] BitNumber Number of bits to set.
+ @param[in] BitMap Pointer to bitmap which covers the Address.
+
+ @return VOID.
+**/
+STATIC
+VOID
+ClearBits (
+ IN EFI_PHYSICAL_ADDRESS Address,
+ IN UINTN BitNumber,
+ IN UINT64 *BitMap
+ )
+{
+ UINTN Lsbs;
+ UINTN Qwords;
+ UINTN Msbs;
+ UINTN StartBit;
+ UINTN EndBit;
+
+ StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+ EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+ if ((StartBit + BitNumber) >= GUARDED_HEAP_MAP_ENTRY_BITS) {
+ Msbs = (GUARDED_HEAP_MAP_ENTRY_BITS - StartBit) %
+ GUARDED_HEAP_MAP_ENTRY_BITS;
+ Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+ Qwords = (BitNumber - Msbs) / GUARDED_HEAP_MAP_ENTRY_BITS;
+ } else {
+ Msbs = BitNumber;
+ Lsbs = 0;
+ Qwords = 0;
+ }
+
+ if (Msbs > 0) {
+ *BitMap &= ~LShiftU64 (LShiftU64 (1, Msbs) - 1, StartBit);
+ BitMap += 1;
+ }
+
+ if (Qwords > 0) {
+ SetMem64 ((VOID *)BitMap, Qwords * GUARDED_HEAP_MAP_ENTRY_BYTES, 0);
+ BitMap += Qwords;
+ }
+
+ if (Lsbs > 0) {
+ *BitMap &= ~(LShiftU64 (1, Lsbs) - 1);
+ }
+}
+
+/**
+ Get corresponding bits in bitmap table according to the address.
+
+ The value of bit 0 corresponds to the status of memory at given Address.
+ No more than 64 bits can be retrieved in one call.
+
+ @param[in] Address Start address to retrieve bits for.
+ @param[in] BitNumber Number of bits to get.
+ @param[in] BitMap Pointer to bitmap which covers the Address.
+
+ @return An integer containing the bits information.
+**/
+STATIC
+UINT64
+GetBits (
+ IN EFI_PHYSICAL_ADDRESS Address,
+ IN UINTN BitNumber,
+ IN UINT64 *BitMap
+ )
+{
+ UINTN StartBit;
+ UINTN EndBit;
+ UINTN Lsbs;
+ UINTN Msbs;
+ UINT64 Result;
+
+ ASSERT (BitNumber <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+ StartBit = (UINTN)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address);
+ EndBit = (StartBit + BitNumber - 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+
+ if ((StartBit + BitNumber) > GUARDED_HEAP_MAP_ENTRY_BITS) {
+ Msbs = GUARDED_HEAP_MAP_ENTRY_BITS - StartBit;
+ Lsbs = (EndBit + 1) % GUARDED_HEAP_MAP_ENTRY_BITS;
+ } else {
+ Msbs = BitNumber;
+ Lsbs = 0;
+ }
+
+ if ((StartBit == 0) && (BitNumber == GUARDED_HEAP_MAP_ENTRY_BITS)) {
+ Result = *BitMap;
+ } else {
+ Result = RShiftU64 ((*BitMap), StartBit) & (LShiftU64 (1, Msbs) - 1);
+ if (Lsbs > 0) {
+ BitMap += 1;
+ Result |= LShiftU64 ((*BitMap) & (LShiftU64 (1, Lsbs) - 1), Msbs);
+ }
+ }
+
+ return Result;
+}
+
+/**
+ Locate the pointer of bitmap from the guarded memory bitmap tables, which
+ covers the given Address.
+
+ @param[in] Address Start address to search the bitmap for.
+ @param[in] AllocMapUnit Flag to indicate memory allocation for the table.
+ @param[out] BitMap Pointer to bitmap which covers the Address.
+
+ @return The bit number from given Address to the end of current map table.
+**/
+UINTN
+FindGuardedMemoryMap (
+ IN EFI_PHYSICAL_ADDRESS Address,
+ IN BOOLEAN AllocMapUnit,
+ OUT UINT64 **BitMap
+ )
+{
+ UINTN Level;
+ UINT64 *GuardMap;
+ UINT64 MapMemory;
+ UINTN Index;
+ UINTN Size;
+ UINTN BitsToUnitEnd;
+ EFI_STATUS Status;
+
+ MapMemory = 0;
+
+ //
+ // Adjust current map table depth according to the address to access
+ //
+ while (AllocMapUnit &&
+ mMapLevel < GUARDED_HEAP_MAP_TABLE_DEPTH &&
+ RShiftU64 (
+ Address,
+ mLevelShift[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1]
+ ) != 0)
+ {
+ if (mGuardedMemoryMap != 0) {
+ Size = (mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel - 1] + 1)
+ * GUARDED_HEAP_MAP_ENTRY_BYTES;
+ Status = CoreInternalAllocatePages (
+ AllocateAnyPages,
+ EfiBootServicesData,
+ EFI_SIZE_TO_PAGES (Size),
+ &MapMemory,
+ FALSE
+ );
+ ASSERT_EFI_ERROR (Status);
+ ASSERT (MapMemory != 0);
+
+ SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+
+ *(UINT64 *)(UINTN)MapMemory = mGuardedMemoryMap;
+ mGuardedMemoryMap = MapMemory;
+ }
+
+ mMapLevel++;
+ }
+
+ GuardMap = &mGuardedMemoryMap;
+ for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+ Level < GUARDED_HEAP_MAP_TABLE_DEPTH;
+ ++Level)
+ {
+ if (*GuardMap == 0) {
+ if (!AllocMapUnit) {
+ GuardMap = NULL;
+ break;
+ }
+
+ Size = (mLevelMask[Level] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES;
+ Status = CoreInternalAllocatePages (
+ AllocateAnyPages,
+ EfiBootServicesData,
+ EFI_SIZE_TO_PAGES (Size),
+ &MapMemory,
+ FALSE
+ );
+ ASSERT_EFI_ERROR (Status);
+ ASSERT (MapMemory != 0);
+
+ SetMem ((VOID *)(UINTN)MapMemory, Size, 0);
+ *GuardMap = MapMemory;
+ }
+
+ Index = (UINTN)RShiftU64 (Address, mLevelShift[Level]);
+ Index &= mLevelMask[Level];
+ GuardMap = (UINT64 *)(UINTN)((*GuardMap) + Index * sizeof (UINT64));
+ }
+
+ BitsToUnitEnd = GUARDED_HEAP_MAP_BITS - GUARDED_HEAP_MAP_BIT_INDEX (Address);
+ *BitMap = GuardMap;
+
+ return BitsToUnitEnd;
+}
+
+/**
+ Set corresponding bits in bitmap table to 1 according to given memory range.
+
+ @param[in] Address Memory address to guard from.
+ @param[in] NumberOfPages Number of pages to guard.
+
+ @return VOID.
+**/
+VOID
+EFIAPI
+SetGuardedMemoryBits (
+ IN EFI_PHYSICAL_ADDRESS Address,
+ IN UINTN NumberOfPages
+ )
+{
+ UINT64 *BitMap;
+ UINTN Bits;
+ UINTN BitsToUnitEnd;
+
+ while (NumberOfPages > 0) {
+ BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+ ASSERT (BitMap != NULL);
+
+ if (NumberOfPages > BitsToUnitEnd) {
+ // Cross map unit
+ Bits = BitsToUnitEnd;
+ } else {
+ Bits = NumberOfPages;
+ }
+
+ SetBits (Address, Bits, BitMap);
+
+ NumberOfPages -= Bits;
+ Address += EFI_PAGES_TO_SIZE (Bits);
+ }
+}
+
+/**
+ Clear corresponding bits in bitmap table according to given memory range.
+
+ @param[in] Address Memory address to unset from.
+ @param[in] NumberOfPages Number of pages to unset guard.
+
+ @return VOID.
+**/
+VOID
+EFIAPI
+ClearGuardedMemoryBits (
+ IN EFI_PHYSICAL_ADDRESS Address,
+ IN UINTN NumberOfPages
+ )
+{
+ UINT64 *BitMap;
+ UINTN Bits;
+ UINTN BitsToUnitEnd;
+
+ while (NumberOfPages > 0) {
+ BitsToUnitEnd = FindGuardedMemoryMap (Address, TRUE, &BitMap);
+ ASSERT (BitMap != NULL);
+
+ if (NumberOfPages > BitsToUnitEnd) {
+ // Cross map unit
+ Bits = BitsToUnitEnd;
+ } else {
+ Bits = NumberOfPages;
+ }
+
+ ClearBits (Address, Bits, BitMap);
+
+ NumberOfPages -= Bits;
+ Address += EFI_PAGES_TO_SIZE (Bits);
+ }
+}
+
+/**
+ Retrieve corresponding bits in bitmap table according to given memory range.
+
+ @param[in] Address Memory address to retrieve from.
+ @param[in] NumberOfPages Number of pages to retrieve.
+
+ @return An integer containing the guarded memory bitmap.
+**/
+UINT64
+GetGuardedMemoryBits (
+ IN EFI_PHYSICAL_ADDRESS Address,
+ IN UINTN NumberOfPages
+ )
+{
+ UINT64 *BitMap;
+ UINTN Bits;
+ UINT64 Result;
+ UINTN Shift;
+ UINTN BitsToUnitEnd;
+
+ ASSERT (NumberOfPages <= GUARDED_HEAP_MAP_ENTRY_BITS);
+
+ Result = 0;
+ Shift = 0;
+ while (NumberOfPages > 0) {
+ BitsToUnitEnd = FindGuardedMemoryMap (Address, FALSE, &BitMap);
+
+ if (NumberOfPages > BitsToUnitEnd) {
+ // Cross map unit
+ Bits = BitsToUnitEnd;
+ } else {
+ Bits = NumberOfPages;
+ }
+
+ if (BitMap != NULL) {
+ Result |= LShiftU64 (GetBits (Address, Bits, BitMap), Shift);
+ }
+
+ Shift += Bits;
+ NumberOfPages -= Bits;
+ Address += EFI_PAGES_TO_SIZE (Bits);
+ }
+
+ return Result;
+}
+
+/**
+ Get bit value in bitmap table for the given address.
+
+ @param[in] Address The address to retrieve for.
+
+ @return 1 or 0.
+**/
+UINTN
+EFIAPI
+GetGuardMapBit (
+ IN EFI_PHYSICAL_ADDRESS Address
+ )
+{
+ UINT64 *GuardMap;
+
+ FindGuardedMemoryMap (Address, FALSE, &GuardMap);
+ if (GuardMap != NULL) {
+ if (RShiftU64 (
+ *GuardMap,
+ GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address)
+ ) & 1)
+ {
+ return 1;
+ }
+ }
+
+ return 0;
+}
+
+/**
+ Check to see if the page at the given address is a Guard page or not.
+
+ @param[in] Address The address to check for.
+
+ @return TRUE The page at Address is a Guard page.
+ @return FALSE The page at Address is not a Guard page.
+**/
+BOOLEAN
+EFIAPI
+IsGuardPage (
+ IN EFI_PHYSICAL_ADDRESS Address
+ )
+{
+ UINT64 BitMap;
+
+ //
+ // There must be at least one guarded page before and/or after given
+ // address if it's a Guard page. The bitmap pattern should be one of
+ // 001, 100 and 101
+ //
+ BitMap = GetGuardedMemoryBits (Address - EFI_PAGE_SIZE, 3);
+ return ((BitMap == BIT0) || (BitMap == BIT2) || (BitMap == (BIT2 | BIT0)));
+}
+
+/**
+ Check to see if the page at the given address is guarded or not.
+
+ @param[in] Address The address to check for.
+
+ @return TRUE The page at Address is guarded.
+ @return FALSE The page at Address is not guarded.
+**/
+BOOLEAN
+EFIAPI
+IsMemoryGuarded (
+ IN EFI_PHYSICAL_ADDRESS Address
+ )
+{
+ return (GetGuardMapBit (Address) == 1);
+}
+
+/**
+ Set the page at the given address to be a Guard page.
+
+ This is done by changing the page table attribute to be NOT PRSENT.
+
+ @param[in] BaseAddress Page address to Guard at
+
+ @return VOID
+**/
+VOID
+EFIAPI
+SetGuardPage (
+ IN EFI_PHYSICAL_ADDRESS BaseAddress
+ )
+{
+ EFI_STATUS Status;
+
+ if (gCpu == NULL) {
+ return;
+ }
+
+ //
+ // Set flag to make sure allocating memory without GUARD for page table
+ // operation; otherwise infinite loops could be caused.
+ //
+ mOnGuarding = TRUE;
+ //
+ // Note: This might overwrite other attributes needed by other features,
+ // such as NX memory protection.
+ //
+ Status = gCpu->SetMemoryAttributes (gCpu, BaseAddress, EFI_PAGE_SIZE, EFI_MEMORY_RP);
+ ASSERT_EFI_ERROR (Status);
+ mOnGuarding = FALSE;
+}
+
+/**
+ Unset the Guard page at the given address to the normal memory.
+
+ This is done by changing the page table attribute to be PRSENT.
+
+ @param[in] BaseAddress Page address to Guard at.
+
+ @return VOID.
+**/
+VOID
+EFIAPI
+UnsetGuardPage (
+ IN EFI_PHYSICAL_ADDRESS BaseAddress
+ )
+{
+ UINT64 Attributes;
+ EFI_STATUS Status;
+
+ if (gCpu == NULL) {
+ return;
+ }
+
+ //
+ // Once the Guard page is unset, it will be freed back to memory pool. NX
+ // memory protection must be restored for this page if NX is enabled for free
+ // memory.
+ //
+ Attributes = 0;
+ if ((PcdGet64 (PcdDxeNxMemoryProtectionPolicy) & (1 << EfiConventionalMemory)) != 0) {
+ Attributes |= EFI_MEMORY_XP;
+ }
+
+ //
+ // Set flag to make sure allocating memory without GUARD for page table
+ // operation; otherwise infinite loops could be caused.
+ //
+ mOnGuarding = TRUE;
+ //
+ // Note: This might overwrite other attributes needed by other features,
+ // such as memory protection (NX). Please make sure they are not enabled
+ // at the same time.
+ //
+ Status = gCpu->SetMemoryAttributes (gCpu, BaseAddress, EFI_PAGE_SIZE, Attributes);
+ ASSERT_EFI_ERROR (Status);
+ mOnGuarding = FALSE;
+}
+
+/**
+ Check to see if the memory at the given address should be guarded or not.
+
+ @param[in] MemoryType Memory type to check.
+ @param[in] AllocateType Allocation type to check.
+ @param[in] PageOrPool Indicate a page allocation or pool allocation.
+
+
+ @return TRUE The given type of memory should be guarded.
+ @return FALSE The given type of memory should not be guarded.
+**/
+BOOLEAN
+IsMemoryTypeToGuard (
+ IN EFI_MEMORY_TYPE MemoryType,
+ IN EFI_ALLOCATE_TYPE AllocateType,
+ IN UINT8 PageOrPool
+ )
+{
+ UINT64 TestBit;
+ UINT64 ConfigBit;
+
+ if (AllocateType == AllocateAddress) {
+ return FALSE;
+ }
+
+ if ((PcdGet8 (PcdHeapGuardPropertyMask) & PageOrPool) == 0) {
+ return FALSE;
+ }
+
+ if (PageOrPool == GUARD_HEAP_TYPE_POOL) {
+ ConfigBit = PcdGet64 (PcdHeapGuardPoolType);
+ } else if (PageOrPool == GUARD_HEAP_TYPE_PAGE) {
+ ConfigBit = PcdGet64 (PcdHeapGuardPageType);
+ } else {
+ ConfigBit = (UINT64)-1;
+ }
+
+ if ((UINT32)MemoryType >= MEMORY_TYPE_OS_RESERVED_MIN) {
+ TestBit = BIT63;
+ } else if ((UINT32)MemoryType >= MEMORY_TYPE_OEM_RESERVED_MIN) {
+ TestBit = BIT62;
+ } else if (MemoryType < EfiMaxMemoryType) {
+ TestBit = LShiftU64 (1, MemoryType);
+ } else if (MemoryType == EfiMaxMemoryType) {
+ TestBit = (UINT64)-1;
+ } else {
+ TestBit = 0;
+ }
+
+ return ((ConfigBit & TestBit) != 0);
+}
+
+/**
+ Check to see if the pool at the given address should be guarded or not.
+
+ @param[in] MemoryType Pool type to check.
+
+
+ @return TRUE The given type of pool should be guarded.
+ @return FALSE The given type of pool should not be guarded.
+**/
+BOOLEAN
+IsPoolTypeToGuard (
+ IN EFI_MEMORY_TYPE MemoryType
+ )
+{
+ return IsMemoryTypeToGuard (
+ MemoryType,
+ AllocateAnyPages,
+ GUARD_HEAP_TYPE_POOL
+ );
+}
+
+/**
+ Check to see if the page at the given address should be guarded or not.
+
+ @param[in] MemoryType Page type to check.
+ @param[in] AllocateType Allocation type to check.
+
+ @return TRUE The given type of page should be guarded.
+ @return FALSE The given type of page should not be guarded.
+**/
+BOOLEAN
+IsPageTypeToGuard (
+ IN EFI_MEMORY_TYPE MemoryType,
+ IN EFI_ALLOCATE_TYPE AllocateType
+ )
+{
+ return IsMemoryTypeToGuard (MemoryType, AllocateType, GUARD_HEAP_TYPE_PAGE);
+}
+
+/**
+ Check to see if the heap guard is enabled for page and/or pool allocation.
+
+ @param[in] GuardType Specify the sub-type(s) of Heap Guard.
+
+ @return TRUE/FALSE.
+**/
+BOOLEAN
+IsHeapGuardEnabled (
+ UINT8 GuardType
+ )
+{
+ return IsMemoryTypeToGuard (EfiMaxMemoryType, AllocateAnyPages, GuardType);
+}
+
+/**
+ Set head Guard and tail Guard for the given memory range.
+
+ @param[in] Memory Base address of memory to set guard for.
+ @param[in] NumberOfPages Memory size in pages.
+
+ @return VOID
+**/
+VOID
+SetGuardForMemory (
+ IN EFI_PHYSICAL_ADDRESS Memory,
+ IN UINTN NumberOfPages
+ )
+{
+ EFI_PHYSICAL_ADDRESS GuardPage;
+
+ //
+ // Set tail Guard
+ //
+ GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+ if (!IsGuardPage (GuardPage)) {
+ SetGuardPage (GuardPage);
+ }
+
+ // Set head Guard
+ GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+ if (!IsGuardPage (GuardPage)) {
+ SetGuardPage (GuardPage);
+ }
+
+ //
+ // Mark the memory range as Guarded
+ //
+ SetGuardedMemoryBits (Memory, NumberOfPages);
+}
+
+/**
+ Unset head Guard and tail Guard for the given memory range.
+
+ @param[in] Memory Base address of memory to unset guard for.
+ @param[in] NumberOfPages Memory size in pages.
+
+ @return VOID
+**/
+VOID
+UnsetGuardForMemory (
+ IN EFI_PHYSICAL_ADDRESS Memory,
+ IN UINTN NumberOfPages
+ )
+{
+ EFI_PHYSICAL_ADDRESS GuardPage;
+ UINT64 GuardBitmap;
+
+ if (NumberOfPages == 0) {
+ return;
+ }
+
+ //
+ // Head Guard must be one page before, if any.
+ //
+ // MSB-> 1 0 <-LSB
+ // -------------------
+ // Head Guard -> 0 1 -> Don't free Head Guard (shared Guard)
+ // Head Guard -> 0 0 -> Free Head Guard either (not shared Guard)
+ // 1 X -> Don't free first page (need a new Guard)
+ // (it'll be turned into a Guard page later)
+ // -------------------
+ // Start -> -1 -2
+ //
+ GuardPage = Memory - EFI_PAGES_TO_SIZE (1);
+ GuardBitmap = GetGuardedMemoryBits (Memory - EFI_PAGES_TO_SIZE (2), 2);
+ if ((GuardBitmap & BIT1) == 0) {
+ //
+ // Head Guard exists.
+ //
+ if ((GuardBitmap & BIT0) == 0) {
+ //
+ // If the head Guard is not a tail Guard of adjacent memory block,
+ // unset it.
+ //
+ UnsetGuardPage (GuardPage);
+ }
+ } else {
+ //
+ // Pages before memory to free are still in Guard. It's a partial free
+ // case. Turn first page of memory block to free into a new Guard.
+ //
+ SetGuardPage (Memory);
+ }
+
+ //
+ // Tail Guard must be the page after this memory block to free, if any.
+ //
+ // MSB-> 1 0 <-LSB
+ // --------------------
+ // 1 0 <- Tail Guard -> Don't free Tail Guard (shared Guard)
+ // 0 0 <- Tail Guard -> Free Tail Guard either (not shared Guard)
+ // X 1 -> Don't free last page (need a new Guard)
+ // (it'll be turned into a Guard page later)
+ // --------------------
+ // +1 +0 <- End
+ //
+ GuardPage = Memory + EFI_PAGES_TO_SIZE (NumberOfPages);
+ GuardBitmap = GetGuardedMemoryBits (GuardPage, 2);
+ if ((GuardBitmap & BIT0) == 0) {
+ //
+ // Tail Guard exists.
+ //
+ if ((GuardBitmap & BIT1) == 0) {
+ //
+ // If the tail Guard is not a head Guard of adjacent memory block,
+ // free it; otherwise, keep it.
+ //
+ UnsetGuardPage (GuardPage);
+ }
+ } else {
+ //
+ // Pages after memory to free are still in Guard. It's a partial free
+ // case. We need to keep one page to be a head Guard.
+ //
+ SetGuardPage (GuardPage - EFI_PAGES_TO_SIZE (1));
+ }
+
+ //
+ // No matter what, we just clear the mark of the Guarded memory.
+ //
+ ClearGuardedMemoryBits (Memory, NumberOfPages);
+}
+
+/**
+ Adjust address of free memory according to existing and/or required Guard.
+
+ This function will check if there're existing Guard pages of adjacent
+ memory blocks, and try to use it as the Guard page of the memory to be
+ allocated.
+
+ @param[in] Start Start address of free memory block.
+ @param[in] Size Size of free memory block.
+ @param[in] SizeRequested Size of memory to allocate.
+
+ @return The end address of memory block found.
+ @return 0 if no enough space for the required size of memory and its Guard.
+**/
+UINT64
+AdjustMemoryS (
+ IN UINT64 Start,
+ IN UINT64 Size,
+ IN UINT64 SizeRequested
+ )
+{
+ UINT64 Target;
+
+ //
+ // UEFI spec requires that allocated pool must be 8-byte aligned. If it's
+ // indicated to put the pool near the Tail Guard, we need extra bytes to
+ // make sure alignment of the returned pool address.
+ //
+ if ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0) {
+ SizeRequested = ALIGN_VALUE (SizeRequested, 8);
+ }
+
+ Target = Start + Size - SizeRequested;
+ ASSERT (Target >= Start);
+ if (Target == 0) {
+ return 0;
+ }
+
+ if (!IsGuardPage (Start + Size)) {
+ // No Guard at tail to share. One more page is needed.
+ Target -= EFI_PAGES_TO_SIZE (1);
+ }
+
+ // Out of range?
+ if (Target < Start) {
+ return 0;
+ }
+
+ // At the edge?
+ if (Target == Start) {
+ if (!IsGuardPage (Target - EFI_PAGES_TO_SIZE (1))) {
+ // No enough space for a new head Guard if no Guard at head to share.
+ return 0;
+ }
+ }
+
+ // OK, we have enough pages for memory and its Guards. Return the End of the
+ // free space.
+ return Target + SizeRequested - 1;
+}
+
+/**
+ Adjust the start address and number of pages to free according to Guard.
+
+ The purpose of this function is to keep the shared Guard page with adjacent
+ memory block if it's still in guard, or free it if no more sharing. Another
+ is to reserve pages as Guard pages in partial page free situation.
+
+ @param[in,out] Memory Base address of memory to free.
+ @param[in,out] NumberOfPages Size of memory to free.
+
+ @return VOID.
+**/
+VOID
+AdjustMemoryF (
+ IN OUT EFI_PHYSICAL_ADDRESS *Memory,
+ IN OUT UINTN *NumberOfPages
+ )
+{
+ EFI_PHYSICAL_ADDRESS Start;
+ EFI_PHYSICAL_ADDRESS MemoryToTest;
+ UINTN PagesToFree;
+ UINT64 GuardBitmap;
+
+ if ((Memory == NULL) || (NumberOfPages == NULL) || (*NumberOfPages == 0)) {
+ return;
+ }
+
+ Start = *Memory;
+ PagesToFree = *NumberOfPages;
+
+ //
+ // Head Guard must be one page before, if any.
+ //
+ // MSB-> 1 0 <-LSB
+ // -------------------
+ // Head Guard -> 0 1 -> Don't free Head Guard (shared Guard)
+ // Head Guard -> 0 0 -> Free Head Guard either (not shared Guard)
+ // 1 X -> Don't free first page (need a new Guard)
+ // (it'll be turned into a Guard page later)
+ // -------------------
+ // Start -> -1 -2
+ //
+ MemoryToTest = Start - EFI_PAGES_TO_SIZE (2);
+ GuardBitmap = GetGuardedMemoryBits (MemoryToTest, 2);
+ if ((GuardBitmap & BIT1) == 0) {
+ //
+ // Head Guard exists.
+ //
+ if ((GuardBitmap & BIT0) == 0) {
+ //
+ // If the head Guard is not a tail Guard of adjacent memory block,
+ // free it; otherwise, keep it.
+ //
+ Start -= EFI_PAGES_TO_SIZE (1);
+ PagesToFree += 1;
+ }
+ } else {
+ //
+ // No Head Guard, and pages before memory to free are still in Guard. It's a
+ // partial free case. We need to keep one page to be a tail Guard.
+ //
+ Start += EFI_PAGES_TO_SIZE (1);
+ PagesToFree -= 1;
+ }
+
+ //
+ // Tail Guard must be the page after this memory block to free, if any.
+ //
+ // MSB-> 1 0 <-LSB
+ // --------------------
+ // 1 0 <- Tail Guard -> Don't free Tail Guard (shared Guard)
+ // 0 0 <- Tail Guard -> Free Tail Guard either (not shared Guard)
+ // X 1 -> Don't free last page (need a new Guard)
+ // (it'll be turned into a Guard page later)
+ // --------------------
+ // +1 +0 <- End
+ //
+ MemoryToTest = Start + EFI_PAGES_TO_SIZE (PagesToFree);
+ GuardBitmap = GetGuardedMemoryBits (MemoryToTest, 2);
+ if ((GuardBitmap & BIT0) == 0) {
+ //
+ // Tail Guard exists.
+ //
+ if ((GuardBitmap & BIT1) == 0) {
+ //
+ // If the tail Guard is not a head Guard of adjacent memory block,
+ // free it; otherwise, keep it.
+ //
+ PagesToFree += 1;
+ }
+ } else if (PagesToFree > 0) {
+ //
+ // No Tail Guard, and pages after memory to free are still in Guard. It's a
+ // partial free case. We need to keep one page to be a head Guard.
+ //
+ PagesToFree -= 1;
+ }
+
+ *Memory = Start;
+ *NumberOfPages = PagesToFree;
+}
+
+/**
+ Adjust the base and number of pages to really allocate according to Guard.
+
+ @param[in,out] Memory Base address of free memory.
+ @param[in,out] NumberOfPages Size of memory to allocate.
+
+ @return VOID.
+**/
+VOID
+AdjustMemoryA (
+ IN OUT EFI_PHYSICAL_ADDRESS *Memory,
+ IN OUT UINTN *NumberOfPages
+ )
+{
+ //
+ // FindFreePages() has already taken the Guard into account. It's safe to
+ // adjust the start address and/or number of pages here, to make sure that
+ // the Guards are also "allocated".
+ //
+ if (!IsGuardPage (*Memory + EFI_PAGES_TO_SIZE (*NumberOfPages))) {
+ // No tail Guard, add one.
+ *NumberOfPages += 1;
+ }
+
+ if (!IsGuardPage (*Memory - EFI_PAGE_SIZE)) {
+ // No head Guard, add one.
+ *Memory -= EFI_PAGE_SIZE;
+ *NumberOfPages += 1;
+ }
+}
+
+/**
+ Adjust the pool head position to make sure the Guard page is adjavent to
+ pool tail or pool head.
+
+ @param[in] Memory Base address of memory allocated.
+ @param[in] NoPages Number of pages actually allocated.
+ @param[in] Size Size of memory requested.
+ (plus pool head/tail overhead)
+
+ @return Address of pool head.
+**/
+VOID *
+AdjustPoolHeadA (
+ IN EFI_PHYSICAL_ADDRESS Memory,
+ IN UINTN NoPages,
+ IN UINTN Size
+ )
+{
+ if ((Memory == 0) || ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0)) {
+ //
+ // Pool head is put near the head Guard
+ //
+ return (VOID *)(UINTN)Memory;
+ }
+
+ //
+ // Pool head is put near the tail Guard
+ //
+ Size = ALIGN_VALUE (Size, 8);
+ return (VOID *)(UINTN)(Memory + EFI_PAGES_TO_SIZE (NoPages) - Size);
+}
+
+/**
+ Get the page base address according to pool head address.
+
+ @param[in] Memory Head address of pool to free.
+
+ @return Address of pool head.
+**/
+VOID *
+AdjustPoolHeadF (
+ IN EFI_PHYSICAL_ADDRESS Memory
+ )
+{
+ if ((Memory == 0) || ((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) != 0)) {
+ //
+ // Pool head is put near the head Guard
+ //
+ return (VOID *)(UINTN)Memory;
+ }
+
+ //
+ // Pool head is put near the tail Guard
+ //
+ return (VOID *)(UINTN)(Memory & ~EFI_PAGE_MASK);
+}
+
+/**
+ Allocate or free guarded memory.
+
+ @param[in] Start Start address of memory to allocate or free.
+ @param[in] NumberOfPages Memory size in pages.
+ @param[in] NewType Memory type to convert to.
+
+ @return VOID.
+**/
+EFI_STATUS
+CoreConvertPagesWithGuard (
+ IN UINT64 Start,
+ IN UINTN NumberOfPages,
+ IN EFI_MEMORY_TYPE NewType
+ )
+{
+ UINT64 OldStart;
+ UINTN OldPages;
+
+ if (NewType == EfiConventionalMemory) {
+ OldStart = Start;
+ OldPages = NumberOfPages;
+
+ AdjustMemoryF (&Start, &NumberOfPages);
+ //
+ // It's safe to unset Guard page inside memory lock because there should
+ // be no memory allocation occurred in updating memory page attribute at
+ // this point. And unsetting Guard page before free will prevent Guard
+ // page just freed back to pool from being allocated right away before
+ // marking it usable (from non-present to present).
+ //
+ UnsetGuardForMemory (OldStart, OldPages);
+ if (NumberOfPages == 0) {
+ return EFI_SUCCESS;
+ }
+ } else {
+ AdjustMemoryA (&Start, &NumberOfPages);
+ }
+
+ return CoreConvertPages (Start, NumberOfPages, NewType);
+}
+
+/**
+ Set all Guard pages which cannot be set before CPU Arch Protocol installed.
+**/
+VOID
+SetAllGuardPages (
+ VOID
+ )
+{
+ UINTN Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINTN Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINTN Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINT64 Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINT64 Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINT64 TableEntry;
+ UINT64 Address;
+ UINT64 GuardPage;
+ INTN Level;
+ UINTN Index;
+ BOOLEAN OnGuarding;
+
+ if ((mGuardedMemoryMap == 0) ||
+ (mMapLevel == 0) ||
+ (mMapLevel > GUARDED_HEAP_MAP_TABLE_DEPTH))
+ {
+ return;
+ }
+
+ CopyMem (Entries, mLevelMask, sizeof (Entries));
+ CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+ SetMem (Tables, sizeof (Tables), 0);
+ SetMem (Addresses, sizeof (Addresses), 0);
+ SetMem (Indices, sizeof (Indices), 0);
+
+ Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+ Tables[Level] = mGuardedMemoryMap;
+ Address = 0;
+ OnGuarding = FALSE;
+
+ DEBUG_CODE (
+ DumpGuardedMemoryBitmap ();
+ );
+
+ while (TRUE) {
+ if (Indices[Level] > Entries[Level]) {
+ Tables[Level] = 0;
+ Level -= 1;
+ } else {
+ TableEntry = ((UINT64 *)(UINTN)(Tables[Level]))[Indices[Level]];
+ Address = Addresses[Level];
+
+ if (TableEntry == 0) {
+ OnGuarding = FALSE;
+ } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+ Level += 1;
+ Tables[Level] = TableEntry;
+ Addresses[Level] = Address;
+ Indices[Level] = 0;
+
+ continue;
+ } else {
+ Index = 0;
+ while (Index < GUARDED_HEAP_MAP_ENTRY_BITS) {
+ if ((TableEntry & 1) == 1) {
+ if (OnGuarding) {
+ GuardPage = 0;
+ } else {
+ GuardPage = Address - EFI_PAGE_SIZE;
+ }
+
+ OnGuarding = TRUE;
+ } else {
+ if (OnGuarding) {
+ GuardPage = Address;
+ } else {
+ GuardPage = 0;
+ }
+
+ OnGuarding = FALSE;
+ }
+
+ if (GuardPage != 0) {
+ SetGuardPage (GuardPage);
+ }
+
+ if (TableEntry == 0) {
+ break;
+ }
+
+ TableEntry = RShiftU64 (TableEntry, 1);
+ Address += EFI_PAGE_SIZE;
+ Index += 1;
+ }
+ }
+ }
+
+ if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+ break;
+ }
+
+ Indices[Level] += 1;
+ Address = (Level == 0) ? 0 : Addresses[Level - 1];
+ Addresses[Level] = Address | LShiftU64 (Indices[Level], Shifts[Level]);
+ }
+}
+
+/**
+ Find the address of top-most guarded free page.
+
+ @param[out] Address Start address of top-most guarded free page.
+
+ @return VOID.
+**/
+VOID
+GetLastGuardedFreePageAddress (
+ OUT EFI_PHYSICAL_ADDRESS *Address
+ )
+{
+ EFI_PHYSICAL_ADDRESS AddressGranularity;
+ EFI_PHYSICAL_ADDRESS BaseAddress;
+ UINTN Level;
+ UINT64 Map;
+ INTN Index;
+
+ ASSERT (mMapLevel >= 1);
+
+ BaseAddress = 0;
+ Map = mGuardedMemoryMap;
+ for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+ Level < GUARDED_HEAP_MAP_TABLE_DEPTH;
+ ++Level)
+ {
+ AddressGranularity = LShiftU64 (1, mLevelShift[Level]);
+
+ //
+ // Find the non-NULL entry at largest index.
+ //
+ for (Index = (INTN)mLevelMask[Level]; Index >= 0; --Index) {
+ if (((UINT64 *)(UINTN)Map)[Index] != 0) {
+ BaseAddress += MultU64x32 (AddressGranularity, (UINT32)Index);
+ Map = ((UINT64 *)(UINTN)Map)[Index];
+ break;
+ }
+ }
+ }
+
+ //
+ // Find the non-zero MSB then get the page address.
+ //
+ while (Map != 0) {
+ Map = RShiftU64 (Map, 1);
+ BaseAddress += EFI_PAGES_TO_SIZE (1);
+ }
+
+ *Address = BaseAddress;
+}
+
+/**
+ Record freed pages.
+
+ @param[in] BaseAddress Base address of just freed pages.
+ @param[in] Pages Number of freed pages.
+
+ @return VOID.
+**/
+VOID
+MarkFreedPages (
+ IN EFI_PHYSICAL_ADDRESS BaseAddress,
+ IN UINTN Pages
+ )
+{
+ SetGuardedMemoryBits (BaseAddress, Pages);
+}
+
+/**
+ Record freed pages as well as mark them as not-present.
+
+ @param[in] BaseAddress Base address of just freed pages.
+ @param[in] Pages Number of freed pages.
+
+ @return VOID.
+**/
+VOID
+EFIAPI
+GuardFreedPages (
+ IN EFI_PHYSICAL_ADDRESS BaseAddress,
+ IN UINTN Pages
+ )
+{
+ EFI_STATUS Status;
+
+ //
+ // Legacy memory lower than 1MB might be accessed with no allocation. Leave
+ // them alone.
+ //
+ if (BaseAddress < BASE_1MB) {
+ return;
+ }
+
+ MarkFreedPages (BaseAddress, Pages);
+ if (gCpu != NULL) {
+ //
+ // Set flag to make sure allocating memory without GUARD for page table
+ // operation; otherwise infinite loops could be caused.
+ //
+ mOnGuarding = TRUE;
+ //
+ // Note: This might overwrite other attributes needed by other features,
+ // such as NX memory protection.
+ //
+ Status = gCpu->SetMemoryAttributes (
+ gCpu,
+ BaseAddress,
+ EFI_PAGES_TO_SIZE (Pages),
+ EFI_MEMORY_RP
+ );
+ //
+ // Normally we should ASSERT the returned Status. But there might be memory
+ // alloc/free involved in SetMemoryAttributes(), which might fail this
+ // calling. It's rare case so it's OK to let a few tiny holes be not-guarded.
+ //
+ if (EFI_ERROR (Status)) {
+ DEBUG ((DEBUG_WARN, "Failed to guard freed pages: %p (%lu)\n", BaseAddress, (UINT64)Pages));
+ }
+
+ mOnGuarding = FALSE;
+ }
+}
+
+/**
+ Record freed pages as well as mark them as not-present, if enabled.
+
+ @param[in] BaseAddress Base address of just freed pages.
+ @param[in] Pages Number of freed pages.
+
+ @return VOID.
+**/
+VOID
+EFIAPI
+GuardFreedPagesChecked (
+ IN EFI_PHYSICAL_ADDRESS BaseAddress,
+ IN UINTN Pages
+ )
+{
+ if (IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED)) {
+ GuardFreedPages (BaseAddress, Pages);
+ }
+}
+
+/**
+ Mark all pages freed before CPU Arch Protocol as not-present.
+
+**/
+VOID
+GuardAllFreedPages (
+ VOID
+ )
+{
+ UINTN Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINTN Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINTN Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINT64 Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINT64 Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINT64 TableEntry;
+ UINT64 Address;
+ UINT64 GuardPage;
+ INTN Level;
+ UINT64 BitIndex;
+ UINTN GuardPageNumber;
+
+ if ((mGuardedMemoryMap == 0) ||
+ (mMapLevel == 0) ||
+ (mMapLevel > GUARDED_HEAP_MAP_TABLE_DEPTH))
+ {
+ return;
+ }
+
+ CopyMem (Entries, mLevelMask, sizeof (Entries));
+ CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+ SetMem (Tables, sizeof (Tables), 0);
+ SetMem (Addresses, sizeof (Addresses), 0);
+ SetMem (Indices, sizeof (Indices), 0);
+
+ Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+ Tables[Level] = mGuardedMemoryMap;
+ Address = 0;
+ GuardPage = (UINT64)-1;
+ GuardPageNumber = 0;
+
+ while (TRUE) {
+ if (Indices[Level] > Entries[Level]) {
+ Tables[Level] = 0;
+ Level -= 1;
+ } else {
+ TableEntry = ((UINT64 *)(UINTN)(Tables[Level]))[Indices[Level]];
+ Address = Addresses[Level];
+
+ if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+ Level += 1;
+ Tables[Level] = TableEntry;
+ Addresses[Level] = Address;
+ Indices[Level] = 0;
+
+ continue;
+ } else {
+ BitIndex = 1;
+ while (BitIndex != 0) {
+ if ((TableEntry & BitIndex) != 0) {
+ if (GuardPage == (UINT64)-1) {
+ GuardPage = Address;
+ }
+
+ ++GuardPageNumber;
+ } else if (GuardPageNumber > 0) {
+ GuardFreedPages (GuardPage, GuardPageNumber);
+ GuardPageNumber = 0;
+ GuardPage = (UINT64)-1;
+ }
+
+ if (TableEntry == 0) {
+ break;
+ }
+
+ Address += EFI_PAGES_TO_SIZE (1);
+ BitIndex = LShiftU64 (BitIndex, 1);
+ }
+ }
+ }
+
+ if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+ break;
+ }
+
+ Indices[Level] += 1;
+ Address = (Level == 0) ? 0 : Addresses[Level - 1];
+ Addresses[Level] = Address | LShiftU64 (Indices[Level], Shifts[Level]);
+ }
+
+ //
+ // Update the maximum address of freed page which can be used for memory
+ // promotion upon out-of-memory-space.
+ //
+ GetLastGuardedFreePageAddress (&Address);
+ if (Address != 0) {
+ mLastPromotedPage = Address;
+ }
+}
+
+/**
+ This function checks to see if the given memory map descriptor in a memory map
+ can be merged with any guarded free pages.
+
+ @param MemoryMapEntry A pointer to a descriptor in MemoryMap.
+ @param MaxAddress Maximum address to stop the merge.
+
+ @return VOID
+
+**/
+VOID
+MergeGuardPages (
+ IN EFI_MEMORY_DESCRIPTOR *MemoryMapEntry,
+ IN EFI_PHYSICAL_ADDRESS MaxAddress
+ )
+{
+ EFI_PHYSICAL_ADDRESS EndAddress;
+ UINT64 Bitmap;
+ INTN Pages;
+
+ if (!IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED) ||
+ (MemoryMapEntry->Type >= EfiMemoryMappedIO))
+ {
+ return;
+ }
+
+ Bitmap = 0;
+ Pages = EFI_SIZE_TO_PAGES ((UINTN)(MaxAddress - MemoryMapEntry->PhysicalStart));
+ Pages -= (INTN)MemoryMapEntry->NumberOfPages;
+ while (Pages > 0) {
+ if (Bitmap == 0) {
+ EndAddress = MemoryMapEntry->PhysicalStart +
+ EFI_PAGES_TO_SIZE ((UINTN)MemoryMapEntry->NumberOfPages);
+ Bitmap = GetGuardedMemoryBits (EndAddress, GUARDED_HEAP_MAP_ENTRY_BITS);
+ }
+
+ if ((Bitmap & 1) == 0) {
+ break;
+ }
+
+ Pages--;
+ MemoryMapEntry->NumberOfPages++;
+ Bitmap = RShiftU64 (Bitmap, 1);
+ }
+}
+
+/**
+ Put part (at most 64 pages a time) guarded free pages back to free page pool.
+
+ Freed memory guard is used to detect Use-After-Free (UAF) memory issue, which
+ makes use of 'Used then throw away' way to detect any illegal access to freed
+ memory. The thrown-away memory will be marked as not-present so that any access
+ to those memory (after free) will be caught by page-fault exception.
+
+ The problem is that this will consume lots of memory space. Once no memory
+ left in pool to allocate, we have to restore part of the freed pages to their
+ normal function. Otherwise the whole system will stop functioning.
+
+ @param StartAddress Start address of promoted memory.
+ @param EndAddress End address of promoted memory.
+
+ @return TRUE Succeeded to promote memory.
+ @return FALSE No free memory found.
+
+**/
+BOOLEAN
+PromoteGuardedFreePages (
+ OUT EFI_PHYSICAL_ADDRESS *StartAddress,
+ OUT EFI_PHYSICAL_ADDRESS *EndAddress
+ )
+{
+ EFI_STATUS Status;
+ UINTN AvailablePages;
+ UINT64 Bitmap;
+ EFI_PHYSICAL_ADDRESS Start;
+
+ if (!IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED)) {
+ return FALSE;
+ }
+
+ //
+ // Similar to memory allocation service, always search the freed pages in
+ // descending direction.
+ //
+ Start = mLastPromotedPage;
+ AvailablePages = 0;
+ while (AvailablePages == 0) {
+ Start -= EFI_PAGES_TO_SIZE (GUARDED_HEAP_MAP_ENTRY_BITS);
+ //
+ // If the address wraps around, try the really freed pages at top.
+ //
+ if (Start > mLastPromotedPage) {
+ GetLastGuardedFreePageAddress (&Start);
+ ASSERT (Start != 0);
+ Start -= EFI_PAGES_TO_SIZE (GUARDED_HEAP_MAP_ENTRY_BITS);
+ }
+
+ Bitmap = GetGuardedMemoryBits (Start, GUARDED_HEAP_MAP_ENTRY_BITS);
+ while (Bitmap > 0) {
+ if ((Bitmap & 1) != 0) {
+ ++AvailablePages;
+ } else if (AvailablePages == 0) {
+ Start += EFI_PAGES_TO_SIZE (1);
+ } else {
+ break;
+ }
+
+ Bitmap = RShiftU64 (Bitmap, 1);
+ }
+ }
+
+ if (AvailablePages != 0) {
+ DEBUG ((DEBUG_INFO, "Promoted pages: %lX (%lx)\r\n", Start, (UINT64)AvailablePages));
+ ClearGuardedMemoryBits (Start, AvailablePages);
+
+ if (gCpu != NULL) {
+ //
+ // Set flag to make sure allocating memory without GUARD for page table
+ // operation; otherwise infinite loops could be caused.
+ //
+ mOnGuarding = TRUE;
+ Status = gCpu->SetMemoryAttributes (gCpu, Start, EFI_PAGES_TO_SIZE (AvailablePages), 0);
+ ASSERT_EFI_ERROR (Status);
+ mOnGuarding = FALSE;
+ }
+
+ mLastPromotedPage = Start;
+ *StartAddress = Start;
+ *EndAddress = Start + EFI_PAGES_TO_SIZE (AvailablePages) - 1;
+ return TRUE;
+ }
+
+ return FALSE;
+}
+
+/**
+ Notify function used to set all Guard pages before CPU Arch Protocol installed.
+**/
+VOID
+HeapGuardCpuArchProtocolNotify (
+ VOID
+ )
+{
+ ASSERT (gCpu != NULL);
+
+ if (IsHeapGuardEnabled (GUARD_HEAP_TYPE_PAGE|GUARD_HEAP_TYPE_POOL) &&
+ IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED))
+ {
+ DEBUG ((DEBUG_ERROR, "Heap guard and freed memory guard cannot be enabled at the same time.\n"));
+ CpuDeadLoop ();
+ }
+
+ if (IsHeapGuardEnabled (GUARD_HEAP_TYPE_PAGE|GUARD_HEAP_TYPE_POOL)) {
+ SetAllGuardPages ();
+ }
+
+ if (IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED)) {
+ GuardAllFreedPages ();
+ }
+}
+
+/**
+ Helper function to convert a UINT64 value in binary to a string.
+
+ @param[in] Value Value of a UINT64 integer.
+ @param[out] BinString String buffer to contain the conversion result.
+
+ @return VOID.
+**/
+VOID
+Uint64ToBinString (
+ IN UINT64 Value,
+ OUT CHAR8 *BinString
+ )
+{
+ UINTN Index;
+
+ if (BinString == NULL) {
+ return;
+ }
+
+ for (Index = 64; Index > 0; --Index) {
+ BinString[Index - 1] = '0' + (Value & 1);
+ Value = RShiftU64 (Value, 1);
+ }
+
+ BinString[64] = '\0';
+}
+
+/**
+ Dump the guarded memory bit map.
+**/
+VOID
+EFIAPI
+DumpGuardedMemoryBitmap (
+ VOID
+ )
+{
+ UINTN Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINTN Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINTN Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINT64 Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINT64 Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];
+ UINT64 TableEntry;
+ UINT64 Address;
+ INTN Level;
+ UINTN RepeatZero;
+ CHAR8 String[GUARDED_HEAP_MAP_ENTRY_BITS + 1];
+ CHAR8 *Ruler1;
+ CHAR8 *Ruler2;
+
+ if (!IsHeapGuardEnabled (GUARD_HEAP_TYPE_ALL)) {
+ return;
+ }
+
+ if ((mGuardedMemoryMap == 0) ||
+ (mMapLevel == 0) ||
+ (mMapLevel > GUARDED_HEAP_MAP_TABLE_DEPTH))
+ {
+ return;
+ }
+
+ Ruler1 = " 3 2 1 0";
+ Ruler2 = "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210";
+
+ DEBUG ((
+ HEAP_GUARD_DEBUG_LEVEL,
+ "============================="
+ " Guarded Memory Bitmap "
+ "==============================\r\n"
+ ));
+ DEBUG ((HEAP_GUARD_DEBUG_LEVEL, " %a\r\n", Ruler1));
+ DEBUG ((HEAP_GUARD_DEBUG_LEVEL, " %a\r\n", Ruler2));
+
+ CopyMem (Entries, mLevelMask, sizeof (Entries));
+ CopyMem (Shifts, mLevelShift, sizeof (Shifts));
+
+ SetMem (Indices, sizeof (Indices), 0);
+ SetMem (Tables, sizeof (Tables), 0);
+ SetMem (Addresses, sizeof (Addresses), 0);
+
+ Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;
+ Tables[Level] = mGuardedMemoryMap;
+ Address = 0;
+ RepeatZero = 0;
+
+ while (TRUE) {
+ if (Indices[Level] > Entries[Level]) {
+ Tables[Level] = 0;
+ Level -= 1;
+ RepeatZero = 0;
+
+ DEBUG ((
+ HEAP_GUARD_DEBUG_LEVEL,
+ "========================================="
+ "=========================================\r\n"
+ ));
+ } else {
+ TableEntry = ((UINT64 *)(UINTN)Tables[Level])[Indices[Level]];
+ Address = Addresses[Level];
+
+ if (TableEntry == 0) {
+ if (Level == GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+ if (RepeatZero == 0) {
+ Uint64ToBinString (TableEntry, String);
+ DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+ } else if (RepeatZero == 1) {
+ DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "... : ...\r\n"));
+ }
+
+ RepeatZero += 1;
+ }
+ } else if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {
+ Level += 1;
+ Tables[Level] = TableEntry;
+ Addresses[Level] = Address;
+ Indices[Level] = 0;
+ RepeatZero = 0;
+
+ continue;
+ } else {
+ RepeatZero = 0;
+ Uint64ToBinString (TableEntry, String);
+ DEBUG ((HEAP_GUARD_DEBUG_LEVEL, "%016lx: %a\r\n", Address, String));
+ }
+ }
+
+ if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {
+ break;
+ }
+
+ Indices[Level] += 1;
+ Address = (Level == 0) ? 0 : Addresses[Level - 1];
+ Addresses[Level] = Address | LShiftU64 (Indices[Level], Shifts[Level]);
+ }
+}