2 UEFI Heap Guard functions.
4 Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>
5 This program and the accompanying materials
6 are licensed and made available under the terms and conditions of the BSD License
7 which accompanies this distribution. The full text of the license may be found at
8 http://opensource.org/licenses/bsd-license.php
10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
15 #include "HeapGuard.h"
18 // Global to avoid infinite reentrance of memory allocation when updating
19 // page table attributes, which may need allocating pages for new PDE/PTE.
21 GLOBAL_REMOVE_IF_UNREFERENCED BOOLEAN mOnGuarding
= FALSE
;
24 // Pointer to table tracking the Guarded memory with bitmap, in which '1'
25 // is used to indicate memory guarded. '0' might be free memory or Guard
26 // page itself, depending on status of memory adjacent to it.
28 GLOBAL_REMOVE_IF_UNREFERENCED UINT64 mGuardedMemoryMap
= 0;
31 // Current depth level of map table pointed by mGuardedMemoryMap.
32 // mMapLevel must be initialized at least by 1. It will be automatically
33 // updated according to the address of memory just tracked.
35 GLOBAL_REMOVE_IF_UNREFERENCED UINTN mMapLevel
= 1;
38 // Shift and mask for each level of map table
40 GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelShift
[GUARDED_HEAP_MAP_TABLE_DEPTH
]
41 = GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS
;
42 GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask
[GUARDED_HEAP_MAP_TABLE_DEPTH
]
43 = GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS
;
46 // SMM memory attribute protocol
48 EDKII_SMM_MEMORY_ATTRIBUTE_PROTOCOL
*mSmmMemoryAttribute
= NULL
;
51 Set corresponding bits in bitmap table to 1 according to the address.
53 @param[in] Address Start address to set for.
54 @param[in] BitNumber Number of bits to set.
55 @param[in] BitMap Pointer to bitmap which covers the Address.
62 IN EFI_PHYSICAL_ADDRESS Address
,
73 StartBit
= (UINTN
)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address
);
74 EndBit
= (StartBit
+ BitNumber
- 1) % GUARDED_HEAP_MAP_ENTRY_BITS
;
76 if ((StartBit
+ BitNumber
) > GUARDED_HEAP_MAP_ENTRY_BITS
) {
77 Msbs
= (GUARDED_HEAP_MAP_ENTRY_BITS
- StartBit
) %
78 GUARDED_HEAP_MAP_ENTRY_BITS
;
79 Lsbs
= (EndBit
+ 1) % GUARDED_HEAP_MAP_ENTRY_BITS
;
80 Qwords
= (BitNumber
- Msbs
) / GUARDED_HEAP_MAP_ENTRY_BITS
;
88 *BitMap
|= LShiftU64 (LShiftU64 (1, Msbs
) - 1, StartBit
);
93 SetMem64 ((VOID
*)BitMap
, Qwords
* GUARDED_HEAP_MAP_ENTRY_BYTES
,
99 *BitMap
|= (LShiftU64 (1, Lsbs
) - 1);
104 Set corresponding bits in bitmap table to 0 according to the address.
106 @param[in] Address Start address to set for.
107 @param[in] BitNumber Number of bits to set.
108 @param[in] BitMap Pointer to bitmap which covers the Address.
115 IN EFI_PHYSICAL_ADDRESS Address
,
126 StartBit
= (UINTN
)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address
);
127 EndBit
= (StartBit
+ BitNumber
- 1) % GUARDED_HEAP_MAP_ENTRY_BITS
;
129 if ((StartBit
+ BitNumber
) > GUARDED_HEAP_MAP_ENTRY_BITS
) {
130 Msbs
= (GUARDED_HEAP_MAP_ENTRY_BITS
- StartBit
) %
131 GUARDED_HEAP_MAP_ENTRY_BITS
;
132 Lsbs
= (EndBit
+ 1) % GUARDED_HEAP_MAP_ENTRY_BITS
;
133 Qwords
= (BitNumber
- Msbs
) / GUARDED_HEAP_MAP_ENTRY_BITS
;
141 *BitMap
&= ~LShiftU64 (LShiftU64 (1, Msbs
) - 1, StartBit
);
146 SetMem64 ((VOID
*)BitMap
, Qwords
* GUARDED_HEAP_MAP_ENTRY_BYTES
, 0);
151 *BitMap
&= ~(LShiftU64 (1, Lsbs
) - 1);
156 Get corresponding bits in bitmap table according to the address.
158 The value of bit 0 corresponds to the status of memory at given Address.
159 No more than 64 bits can be retrieved in one call.
161 @param[in] Address Start address to retrieve bits for.
162 @param[in] BitNumber Number of bits to get.
163 @param[in] BitMap Pointer to bitmap which covers the Address.
165 @return An integer containing the bits information.
170 IN EFI_PHYSICAL_ADDRESS Address
,
181 ASSERT (BitNumber
<= GUARDED_HEAP_MAP_ENTRY_BITS
);
183 StartBit
= (UINTN
)GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address
);
184 EndBit
= (StartBit
+ BitNumber
- 1) % GUARDED_HEAP_MAP_ENTRY_BITS
;
186 if ((StartBit
+ BitNumber
) > GUARDED_HEAP_MAP_ENTRY_BITS
) {
187 Msbs
= GUARDED_HEAP_MAP_ENTRY_BITS
- StartBit
;
188 Lsbs
= (EndBit
+ 1) % GUARDED_HEAP_MAP_ENTRY_BITS
;
194 Result
= RShiftU64 ((*BitMap
), StartBit
) & (LShiftU64 (1, Msbs
) - 1);
197 Result
|= LShiftU64 ((*BitMap
) & (LShiftU64 (1, Lsbs
) - 1), Msbs
);
204 Helper function to allocate pages without Guard for internal uses.
206 @param[in] Pages Page number.
208 @return Address of memory allocated.
216 EFI_PHYSICAL_ADDRESS Memory
;
218 Status
= SmmInternalAllocatePages (AllocateAnyPages
, EfiRuntimeServicesData
,
219 Pages
, &Memory
, FALSE
);
220 if (EFI_ERROR (Status
)) {
224 return (VOID
*)(UINTN
)Memory
;
228 Locate the pointer of bitmap from the guarded memory bitmap tables, which
229 covers the given Address.
231 @param[in] Address Start address to search the bitmap for.
232 @param[in] AllocMapUnit Flag to indicate memory allocation for the table.
233 @param[out] BitMap Pointer to bitmap which covers the Address.
235 @return The bit number from given Address to the end of current map table.
238 FindGuardedMemoryMap (
239 IN EFI_PHYSICAL_ADDRESS Address
,
240 IN BOOLEAN AllocMapUnit
,
252 // Adjust current map table depth according to the address to access
254 while (mMapLevel
< GUARDED_HEAP_MAP_TABLE_DEPTH
258 mLevelShift
[GUARDED_HEAP_MAP_TABLE_DEPTH
- mMapLevel
- 1]
261 if (mGuardedMemoryMap
!= 0) {
262 Size
= (mLevelMask
[GUARDED_HEAP_MAP_TABLE_DEPTH
- mMapLevel
- 1] + 1)
263 * GUARDED_HEAP_MAP_ENTRY_BYTES
;
264 MapMemory
= (UINT64
)(UINTN
)PageAlloc (EFI_SIZE_TO_PAGES (Size
));
265 ASSERT (MapMemory
!= 0);
267 SetMem ((VOID
*)(UINTN
)MapMemory
, Size
, 0);
269 *(UINT64
*)(UINTN
)MapMemory
= mGuardedMemoryMap
;
270 mGuardedMemoryMap
= MapMemory
;
277 GuardMap
= &mGuardedMemoryMap
;
278 for (Level
= GUARDED_HEAP_MAP_TABLE_DEPTH
- mMapLevel
;
279 Level
< GUARDED_HEAP_MAP_TABLE_DEPTH
;
282 if (*GuardMap
== 0) {
288 Size
= (mLevelMask
[Level
] + 1) * GUARDED_HEAP_MAP_ENTRY_BYTES
;
289 MapMemory
= (UINT64
)(UINTN
)PageAlloc (EFI_SIZE_TO_PAGES (Size
));
290 ASSERT (MapMemory
!= 0);
292 SetMem ((VOID
*)(UINTN
)MapMemory
, Size
, 0);
293 *GuardMap
= MapMemory
;
296 Index
= (UINTN
)RShiftU64 (Address
, mLevelShift
[Level
]);
297 Index
&= mLevelMask
[Level
];
298 GuardMap
= (UINT64
*)(UINTN
)((*GuardMap
) + Index
* sizeof (UINT64
));
302 BitsToUnitEnd
= GUARDED_HEAP_MAP_BITS
- GUARDED_HEAP_MAP_BIT_INDEX (Address
);
305 return BitsToUnitEnd
;
309 Set corresponding bits in bitmap table to 1 according to given memory range.
311 @param[in] Address Memory address to guard from.
312 @param[in] NumberOfPages Number of pages to guard.
318 SetGuardedMemoryBits (
319 IN EFI_PHYSICAL_ADDRESS Address
,
320 IN UINTN NumberOfPages
327 while (NumberOfPages
> 0) {
328 BitsToUnitEnd
= FindGuardedMemoryMap (Address
, TRUE
, &BitMap
);
329 ASSERT (BitMap
!= NULL
);
331 if (NumberOfPages
> BitsToUnitEnd
) {
333 Bits
= BitsToUnitEnd
;
335 Bits
= NumberOfPages
;
338 SetBits (Address
, Bits
, BitMap
);
340 NumberOfPages
-= Bits
;
341 Address
+= EFI_PAGES_TO_SIZE (Bits
);
346 Clear corresponding bits in bitmap table according to given memory range.
348 @param[in] Address Memory address to unset from.
349 @param[in] NumberOfPages Number of pages to unset guard.
355 ClearGuardedMemoryBits (
356 IN EFI_PHYSICAL_ADDRESS Address
,
357 IN UINTN NumberOfPages
364 while (NumberOfPages
> 0) {
365 BitsToUnitEnd
= FindGuardedMemoryMap (Address
, TRUE
, &BitMap
);
366 ASSERT (BitMap
!= NULL
);
368 if (NumberOfPages
> BitsToUnitEnd
) {
370 Bits
= BitsToUnitEnd
;
372 Bits
= NumberOfPages
;
375 ClearBits (Address
, Bits
, BitMap
);
377 NumberOfPages
-= Bits
;
378 Address
+= EFI_PAGES_TO_SIZE (Bits
);
383 Retrieve corresponding bits in bitmap table according to given memory range.
385 @param[in] Address Memory address to retrieve from.
386 @param[in] NumberOfPages Number of pages to retrieve.
388 @return An integer containing the guarded memory bitmap.
391 GetGuardedMemoryBits (
392 IN EFI_PHYSICAL_ADDRESS Address
,
393 IN UINTN NumberOfPages
402 ASSERT (NumberOfPages
<= GUARDED_HEAP_MAP_ENTRY_BITS
);
406 while (NumberOfPages
> 0) {
407 BitsToUnitEnd
= FindGuardedMemoryMap (Address
, FALSE
, &BitMap
);
409 if (NumberOfPages
> BitsToUnitEnd
) {
411 Bits
= BitsToUnitEnd
;
413 Bits
= NumberOfPages
;
416 if (BitMap
!= NULL
) {
417 Result
|= LShiftU64 (GetBits (Address
, Bits
, BitMap
), Shift
);
421 NumberOfPages
-= Bits
;
422 Address
+= EFI_PAGES_TO_SIZE (Bits
);
429 Get bit value in bitmap table for the given address.
431 @param[in] Address The address to retrieve for.
438 IN EFI_PHYSICAL_ADDRESS Address
443 FindGuardedMemoryMap (Address
, FALSE
, &GuardMap
);
444 if (GuardMap
!= NULL
) {
445 if (RShiftU64 (*GuardMap
,
446 GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address
)) & 1) {
455 Set the bit in bitmap table for the given address.
457 @param[in] Address The address to set for.
464 IN EFI_PHYSICAL_ADDRESS Address
470 FindGuardedMemoryMap (Address
, TRUE
, &GuardMap
);
471 if (GuardMap
!= NULL
) {
472 BitMask
= LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address
));
473 *GuardMap
|= BitMask
;
478 Clear the bit in bitmap table for the given address.
480 @param[in] Address The address to clear for.
487 IN EFI_PHYSICAL_ADDRESS Address
493 FindGuardedMemoryMap (Address
, TRUE
, &GuardMap
);
494 if (GuardMap
!= NULL
) {
495 BitMask
= LShiftU64 (1, GUARDED_HEAP_MAP_ENTRY_BIT_INDEX (Address
));
496 *GuardMap
&= ~BitMask
;
501 Check to see if the page at the given address is a Guard page or not.
503 @param[in] Address The address to check for.
505 @return TRUE The page at Address is a Guard page.
506 @return FALSE The page at Address is not a Guard page.
511 IN EFI_PHYSICAL_ADDRESS Address
517 // There must be at least one guarded page before and/or after given
518 // address if it's a Guard page. The bitmap pattern should be one of
521 BitMap
= GetGuardedMemoryBits (Address
- EFI_PAGE_SIZE
, 3);
522 return ((BitMap
== BIT0
) || (BitMap
== BIT2
) || (BitMap
== (BIT2
| BIT0
)));
526 Check to see if the page at the given address is a head Guard page or not.
528 @param[in] Address The address to check for.
530 @return TRUE The page at Address is a head Guard page.
531 @return FALSE The page at Address is not a head Guard page.
536 IN EFI_PHYSICAL_ADDRESS Address
539 return (GetGuardedMemoryBits (Address
, 2) == BIT1
);
543 Check to see if the page at the given address is a tail Guard page or not.
545 @param[in] Address The address to check for.
547 @return TRUE The page at Address is a tail Guard page.
548 @return FALSE The page at Address is not a tail Guard page.
553 IN EFI_PHYSICAL_ADDRESS Address
556 return (GetGuardedMemoryBits (Address
- EFI_PAGE_SIZE
, 2) == BIT0
);
560 Check to see if the page at the given address is guarded or not.
562 @param[in] Address The address to check for.
564 @return TRUE The page at Address is guarded.
565 @return FALSE The page at Address is not guarded.
570 IN EFI_PHYSICAL_ADDRESS Address
573 return (GetGuardMapBit (Address
) == 1);
577 Set the page at the given address to be a Guard page.
579 This is done by changing the page table attribute to be NOT PRSENT.
581 @param[in] BaseAddress Page address to Guard at.
588 IN EFI_PHYSICAL_ADDRESS BaseAddress
591 if (mSmmMemoryAttribute
!= NULL
) {
593 mSmmMemoryAttribute
->SetMemoryAttributes (
604 Unset the Guard page at the given address to the normal memory.
606 This is done by changing the page table attribute to be PRSENT.
608 @param[in] BaseAddress Page address to Guard at.
615 IN EFI_PHYSICAL_ADDRESS BaseAddress
618 if (mSmmMemoryAttribute
!= NULL
) {
620 mSmmMemoryAttribute
->ClearMemoryAttributes (
631 Check to see if the memory at the given address should be guarded or not.
633 @param[in] MemoryType Memory type to check.
634 @param[in] AllocateType Allocation type to check.
635 @param[in] PageOrPool Indicate a page allocation or pool allocation.
638 @return TRUE The given type of memory should be guarded.
639 @return FALSE The given type of memory should not be guarded.
642 IsMemoryTypeToGuard (
643 IN EFI_MEMORY_TYPE MemoryType
,
644 IN EFI_ALLOCATE_TYPE AllocateType
,
651 if ((PcdGet8 (PcdHeapGuardPropertyMask
) & PageOrPool
) == 0
653 || AllocateType
== AllocateAddress
) {
658 if ((PageOrPool
& GUARD_HEAP_TYPE_POOL
) != 0) {
659 ConfigBit
|= PcdGet64 (PcdHeapGuardPoolType
);
662 if ((PageOrPool
& GUARD_HEAP_TYPE_PAGE
) != 0) {
663 ConfigBit
|= PcdGet64 (PcdHeapGuardPageType
);
666 if (MemoryType
== EfiRuntimeServicesData
||
667 MemoryType
== EfiRuntimeServicesCode
) {
668 TestBit
= LShiftU64 (1, MemoryType
);
669 } else if (MemoryType
== EfiMaxMemoryType
) {
670 TestBit
= (UINT64
)-1;
675 return ((ConfigBit
& TestBit
) != 0);
679 Check to see if the pool at the given address should be guarded or not.
681 @param[in] MemoryType Pool type to check.
684 @return TRUE The given type of pool should be guarded.
685 @return FALSE The given type of pool should not be guarded.
689 IN EFI_MEMORY_TYPE MemoryType
692 return IsMemoryTypeToGuard (MemoryType
, AllocateAnyPages
,
693 GUARD_HEAP_TYPE_POOL
);
697 Check to see if the page at the given address should be guarded or not.
699 @param[in] MemoryType Page type to check.
700 @param[in] AllocateType Allocation type to check.
702 @return TRUE The given type of page should be guarded.
703 @return FALSE The given type of page should not be guarded.
707 IN EFI_MEMORY_TYPE MemoryType
,
708 IN EFI_ALLOCATE_TYPE AllocateType
711 return IsMemoryTypeToGuard (MemoryType
, AllocateType
, GUARD_HEAP_TYPE_PAGE
);
715 Check to see if the heap guard is enabled for page and/or pool allocation.
724 return IsMemoryTypeToGuard (EfiMaxMemoryType
, AllocateAnyPages
,
725 GUARD_HEAP_TYPE_POOL
|GUARD_HEAP_TYPE_PAGE
);
729 Set head Guard and tail Guard for the given memory range.
731 @param[in] Memory Base address of memory to set guard for.
732 @param[in] NumberOfPages Memory size in pages.
738 IN EFI_PHYSICAL_ADDRESS Memory
,
739 IN UINTN NumberOfPages
742 EFI_PHYSICAL_ADDRESS GuardPage
;
747 GuardPage
= Memory
+ EFI_PAGES_TO_SIZE (NumberOfPages
);
748 if (!IsGuardPage (GuardPage
)) {
749 SetGuardPage (GuardPage
);
753 GuardPage
= Memory
- EFI_PAGES_TO_SIZE (1);
754 if (!IsGuardPage (GuardPage
)) {
755 SetGuardPage (GuardPage
);
759 // Mark the memory range as Guarded
761 SetGuardedMemoryBits (Memory
, NumberOfPages
);
765 Unset head Guard and tail Guard for the given memory range.
767 @param[in] Memory Base address of memory to unset guard for.
768 @param[in] NumberOfPages Memory size in pages.
773 UnsetGuardForMemory (
774 IN EFI_PHYSICAL_ADDRESS Memory
,
775 IN UINTN NumberOfPages
778 EFI_PHYSICAL_ADDRESS GuardPage
;
780 if (NumberOfPages
== 0) {
785 // Head Guard must be one page before, if any.
787 GuardPage
= Memory
- EFI_PAGES_TO_SIZE (1);
788 if (IsHeadGuard (GuardPage
)) {
789 if (!IsMemoryGuarded (GuardPage
- EFI_PAGES_TO_SIZE (1))) {
791 // If the head Guard is not a tail Guard of adjacent memory block,
794 UnsetGuardPage (GuardPage
);
796 } else if (IsMemoryGuarded (GuardPage
)) {
798 // Pages before memory to free are still in Guard. It's a partial free
799 // case. Turn first page of memory block to free into a new Guard.
801 SetGuardPage (Memory
);
805 // Tail Guard must be the page after this memory block to free, if any.
807 GuardPage
= Memory
+ EFI_PAGES_TO_SIZE (NumberOfPages
);
808 if (IsTailGuard (GuardPage
)) {
809 if (!IsMemoryGuarded (GuardPage
+ EFI_PAGES_TO_SIZE (1))) {
811 // If the tail Guard is not a head Guard of adjacent memory block,
812 // free it; otherwise, keep it.
814 UnsetGuardPage (GuardPage
);
816 } else if (IsMemoryGuarded (GuardPage
)) {
818 // Pages after memory to free are still in Guard. It's a partial free
819 // case. We need to keep one page to be a head Guard.
821 SetGuardPage (GuardPage
- EFI_PAGES_TO_SIZE (1));
825 // No matter what, we just clear the mark of the Guarded memory.
827 ClearGuardedMemoryBits(Memory
, NumberOfPages
);
831 Adjust address of free memory according to existing and/or required Guard.
833 This function will check if there're existing Guard pages of adjacent
834 memory blocks, and try to use it as the Guard page of the memory to be
837 @param[in] Start Start address of free memory block.
838 @param[in] Size Size of free memory block.
839 @param[in] SizeRequested Size of memory to allocate.
841 @return The end address of memory block found.
842 @return 0 if no enough space for the required size of memory and its Guard.
848 IN UINT64 SizeRequested
853 Target
= Start
+ Size
- SizeRequested
;
856 // At least one more page needed for Guard page.
858 if (Size
< (SizeRequested
+ EFI_PAGES_TO_SIZE (1))) {
862 if (!IsGuardPage (Start
+ Size
)) {
863 // No Guard at tail to share. One more page is needed.
864 Target
-= EFI_PAGES_TO_SIZE (1);
868 if (Target
< Start
) {
873 if (Target
== Start
) {
874 if (!IsGuardPage (Target
- EFI_PAGES_TO_SIZE (1))) {
875 // No enough space for a new head Guard if no Guard at head to share.
880 // OK, we have enough pages for memory and its Guards. Return the End of the
882 return Target
+ SizeRequested
- 1;
886 Adjust the start address and number of pages to free according to Guard.
888 The purpose of this function is to keep the shared Guard page with adjacent
889 memory block if it's still in guard, or free it if no more sharing. Another
890 is to reserve pages as Guard pages in partial page free situation.
892 @param[in,out] Memory Base address of memory to free.
893 @param[in,out] NumberOfPages Size of memory to free.
899 IN OUT EFI_PHYSICAL_ADDRESS
*Memory
,
900 IN OUT UINTN
*NumberOfPages
903 EFI_PHYSICAL_ADDRESS Start
;
904 EFI_PHYSICAL_ADDRESS MemoryToTest
;
907 if (Memory
== NULL
|| NumberOfPages
== NULL
|| *NumberOfPages
== 0) {
912 PagesToFree
= *NumberOfPages
;
915 // Head Guard must be one page before, if any.
917 MemoryToTest
= Start
- EFI_PAGES_TO_SIZE (1);
918 if (IsHeadGuard (MemoryToTest
)) {
919 if (!IsMemoryGuarded (MemoryToTest
- EFI_PAGES_TO_SIZE (1))) {
921 // If the head Guard is not a tail Guard of adjacent memory block,
922 // free it; otherwise, keep it.
924 Start
-= EFI_PAGES_TO_SIZE (1);
927 } else if (IsMemoryGuarded (MemoryToTest
)) {
929 // Pages before memory to free are still in Guard. It's a partial free
930 // case. We need to keep one page to be a tail Guard.
932 Start
+= EFI_PAGES_TO_SIZE (1);
937 // Tail Guard must be the page after this memory block to free, if any.
939 MemoryToTest
= Start
+ EFI_PAGES_TO_SIZE (PagesToFree
);
940 if (IsTailGuard (MemoryToTest
)) {
941 if (!IsMemoryGuarded (MemoryToTest
+ EFI_PAGES_TO_SIZE (1))) {
943 // If the tail Guard is not a head Guard of adjacent memory block,
944 // free it; otherwise, keep it.
948 } else if (IsMemoryGuarded (MemoryToTest
)) {
950 // Pages after memory to free are still in Guard. It's a partial free
951 // case. We need to keep one page to be a head Guard.
957 *NumberOfPages
= PagesToFree
;
961 Adjust the base and number of pages to really allocate according to Guard.
963 @param[in,out] Memory Base address of free memory.
964 @param[in,out] NumberOfPages Size of memory to allocate.
970 IN OUT EFI_PHYSICAL_ADDRESS
*Memory
,
971 IN OUT UINTN
*NumberOfPages
975 // FindFreePages() has already taken the Guard into account. It's safe to
976 // adjust the start address and/or number of pages here, to make sure that
977 // the Guards are also "allocated".
979 if (!IsGuardPage (*Memory
+ EFI_PAGES_TO_SIZE (*NumberOfPages
))) {
980 // No tail Guard, add one.
984 if (!IsGuardPage (*Memory
- EFI_PAGE_SIZE
)) {
985 // No head Guard, add one.
986 *Memory
-= EFI_PAGE_SIZE
;
992 Adjust the pool head position to make sure the Guard page is adjavent to
993 pool tail or pool head.
995 @param[in] Memory Base address of memory allocated.
996 @param[in] NoPages Number of pages actually allocated.
997 @param[in] Size Size of memory requested.
998 (plus pool head/tail overhead)
1000 @return Address of pool head
1004 IN EFI_PHYSICAL_ADDRESS Memory
,
1009 if ((PcdGet8 (PcdHeapGuardPropertyMask
) & BIT7
) != 0) {
1011 // Pool head is put near the head Guard
1013 return (VOID
*)(UINTN
)Memory
;
1017 // Pool head is put near the tail Guard
1019 return (VOID
*)(UINTN
)(Memory
+ EFI_PAGES_TO_SIZE (NoPages
) - Size
);
1023 Get the page base address according to pool head address.
1025 @param[in] Memory Head address of pool to free.
1027 @return Address of pool head.
1031 IN EFI_PHYSICAL_ADDRESS Memory
1034 if ((PcdGet8 (PcdHeapGuardPropertyMask
) & BIT7
) != 0) {
1036 // Pool head is put near the head Guard
1038 return (VOID
*)(UINTN
)Memory
;
1042 // Pool head is put near the tail Guard
1044 return (VOID
*)(UINTN
)(Memory
& ~EFI_PAGE_MASK
);
1048 Helper function of memory allocation with Guard pages.
1050 @param FreePageList The free page node.
1051 @param NumberOfPages Number of pages to be allocated.
1052 @param MaxAddress Request to allocate memory below this address.
1053 @param MemoryType Type of memory requested.
1055 @return Memory address of allocated pages.
1058 InternalAllocMaxAddressWithGuard (
1059 IN OUT LIST_ENTRY
*FreePageList
,
1060 IN UINTN NumberOfPages
,
1061 IN UINTN MaxAddress
,
1062 IN EFI_MEMORY_TYPE MemoryType
1067 FREE_PAGE_LIST
*Pages
;
1073 for (Node
= FreePageList
->BackLink
; Node
!= FreePageList
;
1074 Node
= Node
->BackLink
) {
1075 Pages
= BASE_CR (Node
, FREE_PAGE_LIST
, Link
);
1076 if (Pages
->NumberOfPages
>= NumberOfPages
&&
1077 (UINTN
)Pages
+ EFI_PAGES_TO_SIZE (NumberOfPages
) - 1 <= MaxAddress
) {
1080 // We may need 1 or 2 more pages for Guard. Check it out.
1082 PagesToAlloc
= NumberOfPages
;
1083 TailGuard
= (UINTN
)Pages
+ EFI_PAGES_TO_SIZE (Pages
->NumberOfPages
);
1084 if (!IsGuardPage (TailGuard
)) {
1086 // Add one if no Guard at the end of current free memory block.
1092 HeadGuard
= (UINTN
)Pages
+
1093 EFI_PAGES_TO_SIZE (Pages
->NumberOfPages
- PagesToAlloc
) -
1095 if (!IsGuardPage (HeadGuard
)) {
1097 // Add one if no Guard at the page before the address to allocate
1103 if (Pages
->NumberOfPages
< PagesToAlloc
) {
1104 // Not enough space to allocate memory with Guards? Try next block.
1108 Address
= InternalAllocPagesOnOneNode (Pages
, PagesToAlloc
, MaxAddress
);
1109 ConvertSmmMemoryMapEntry(MemoryType
, Address
, PagesToAlloc
, FALSE
);
1110 CoreFreeMemoryMapStack();
1111 if (HeadGuard
== 0) {
1112 // Don't pass the Guard page to user.
1113 Address
+= EFI_PAGE_SIZE
;
1115 SetGuardForMemory (Address
, NumberOfPages
);
1124 Helper function of memory free with Guard pages.
1126 @param[in] Memory Base address of memory being freed.
1127 @param[in] NumberOfPages The number of pages to free.
1128 @param[in] AddRegion If this memory is new added region.
1130 @retval EFI_NOT_FOUND Could not find the entry that covers the range.
1131 @retval EFI_INVALID_PARAMETER Address not aligned, Address is zero or NumberOfPages is zero.
1132 @return EFI_SUCCESS Pages successfully freed.
1135 SmmInternalFreePagesExWithGuard (
1136 IN EFI_PHYSICAL_ADDRESS Memory
,
1137 IN UINTN NumberOfPages
,
1138 IN BOOLEAN AddRegion
1141 EFI_PHYSICAL_ADDRESS MemoryToFree
;
1144 MemoryToFree
= Memory
;
1145 PagesToFree
= NumberOfPages
;
1147 AdjustMemoryF (&MemoryToFree
, &PagesToFree
);
1148 UnsetGuardForMemory (Memory
, NumberOfPages
);
1150 return SmmInternalFreePagesEx (MemoryToFree
, PagesToFree
, AddRegion
);
1154 Set all Guard pages which cannot be set during the non-SMM mode time.
1161 UINTN Entries
[GUARDED_HEAP_MAP_TABLE_DEPTH
];
1162 UINTN Shifts
[GUARDED_HEAP_MAP_TABLE_DEPTH
];
1163 UINTN Indices
[GUARDED_HEAP_MAP_TABLE_DEPTH
];
1164 UINT64 Tables
[GUARDED_HEAP_MAP_TABLE_DEPTH
];
1165 UINT64 Addresses
[GUARDED_HEAP_MAP_TABLE_DEPTH
];
1173 if (mGuardedMemoryMap
== 0) {
1177 CopyMem (Entries
, mLevelMask
, sizeof (Entries
));
1178 CopyMem (Shifts
, mLevelShift
, sizeof (Shifts
));
1180 SetMem (Tables
, sizeof(Tables
), 0);
1181 SetMem (Addresses
, sizeof(Addresses
), 0);
1182 SetMem (Indices
, sizeof(Indices
), 0);
1184 Level
= GUARDED_HEAP_MAP_TABLE_DEPTH
- mMapLevel
;
1185 Tables
[Level
] = mGuardedMemoryMap
;
1190 DumpGuardedMemoryBitmap ();
1194 if (Indices
[Level
] > Entries
[Level
]) {
1199 TableEntry
= ((UINT64
*)(UINTN
)(Tables
[Level
]))[Indices
[Level
]];
1200 Address
= Addresses
[Level
];
1202 if (TableEntry
== 0) {
1206 } else if (Level
< GUARDED_HEAP_MAP_TABLE_DEPTH
- 1) {
1209 Tables
[Level
] = TableEntry
;
1210 Addresses
[Level
] = Address
;
1218 while (Index
< GUARDED_HEAP_MAP_ENTRY_BITS
) {
1219 if ((TableEntry
& 1) == 1) {
1223 GuardPage
= Address
- EFI_PAGE_SIZE
;
1228 GuardPage
= Address
;
1235 if (GuardPage
!= 0) {
1236 SetGuardPage (GuardPage
);
1239 if (TableEntry
== 0) {
1243 TableEntry
= RShiftU64 (TableEntry
, 1);
1244 Address
+= EFI_PAGE_SIZE
;
1250 if (Level
< (GUARDED_HEAP_MAP_TABLE_DEPTH
- (INTN
)mMapLevel
)) {
1254 Indices
[Level
] += 1;
1255 Address
= (Level
== 0) ? 0 : Addresses
[Level
- 1];
1256 Addresses
[Level
] = Address
| LShiftU64(Indices
[Level
], Shifts
[Level
]);
1262 Hook function used to set all Guard pages after entering SMM mode.
1265 SmmEntryPointMemoryManagementHook (
1271 if (mSmmMemoryAttribute
== NULL
) {
1272 Status
= SmmLocateProtocol (
1273 &gEdkiiSmmMemoryAttributeProtocolGuid
,
1275 (VOID
**)&mSmmMemoryAttribute
1277 if (!EFI_ERROR(Status
)) {
1278 SetAllGuardPages ();
1284 Helper function to convert a UINT64 value in binary to a string.
1286 @param[in] Value Value of a UINT64 integer.
1287 @param[out] BinString String buffer to contain the conversion result.
1294 OUT CHAR8
*BinString
1299 if (BinString
== NULL
) {
1303 for (Index
= 64; Index
> 0; --Index
) {
1304 BinString
[Index
- 1] = '0' + (Value
& 1);
1305 Value
= RShiftU64 (Value
, 1);
1307 BinString
[64] = '\0';
1311 Dump the guarded memory bit map.
1315 DumpGuardedMemoryBitmap (
1319 UINTN Entries
[GUARDED_HEAP_MAP_TABLE_DEPTH
];
1320 UINTN Shifts
[GUARDED_HEAP_MAP_TABLE_DEPTH
];
1321 UINTN Indices
[GUARDED_HEAP_MAP_TABLE_DEPTH
];
1322 UINT64 Tables
[GUARDED_HEAP_MAP_TABLE_DEPTH
];
1323 UINT64 Addresses
[GUARDED_HEAP_MAP_TABLE_DEPTH
];
1328 CHAR8 String
[GUARDED_HEAP_MAP_ENTRY_BITS
+ 1];
1332 if (mGuardedMemoryMap
== 0) {
1336 Ruler1
= " 3 2 1 0";
1337 Ruler2
= "FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210FEDCBA9876543210";
1339 DEBUG ((HEAP_GUARD_DEBUG_LEVEL
, "============================="
1340 " Guarded Memory Bitmap "
1341 "==============================\r\n"));
1342 DEBUG ((HEAP_GUARD_DEBUG_LEVEL
, " %a\r\n", Ruler1
));
1343 DEBUG ((HEAP_GUARD_DEBUG_LEVEL
, " %a\r\n", Ruler2
));
1345 CopyMem (Entries
, mLevelMask
, sizeof (Entries
));
1346 CopyMem (Shifts
, mLevelShift
, sizeof (Shifts
));
1348 SetMem (Indices
, sizeof(Indices
), 0);
1349 SetMem (Tables
, sizeof(Tables
), 0);
1350 SetMem (Addresses
, sizeof(Addresses
), 0);
1352 Level
= GUARDED_HEAP_MAP_TABLE_DEPTH
- mMapLevel
;
1353 Tables
[Level
] = mGuardedMemoryMap
;
1358 if (Indices
[Level
] > Entries
[Level
]) {
1365 HEAP_GUARD_DEBUG_LEVEL
,
1366 "========================================="
1367 "=========================================\r\n"
1372 TableEntry
= ((UINT64
*)(UINTN
)Tables
[Level
])[Indices
[Level
]];
1373 Address
= Addresses
[Level
];
1375 if (TableEntry
== 0) {
1377 if (Level
== GUARDED_HEAP_MAP_TABLE_DEPTH
- 1) {
1378 if (RepeatZero
== 0) {
1379 Uint64ToBinString(TableEntry
, String
);
1380 DEBUG ((HEAP_GUARD_DEBUG_LEVEL
, "%016lx: %a\r\n", Address
, String
));
1381 } else if (RepeatZero
== 1) {
1382 DEBUG ((HEAP_GUARD_DEBUG_LEVEL
, "... : ...\r\n"));
1387 } else if (Level
< GUARDED_HEAP_MAP_TABLE_DEPTH
- 1) {
1390 Tables
[Level
] = TableEntry
;
1391 Addresses
[Level
] = Address
;
1400 Uint64ToBinString(TableEntry
, String
);
1401 DEBUG ((HEAP_GUARD_DEBUG_LEVEL
, "%016lx: %a\r\n", Address
, String
));
1406 if (Level
< (GUARDED_HEAP_MAP_TABLE_DEPTH
- (INTN
)mMapLevel
)) {
1410 Indices
[Level
] += 1;
1411 Address
= (Level
== 0) ? 0 : Addresses
[Level
- 1];
1412 Addresses
[Level
] = Address
| LShiftU64(Indices
[Level
], Shifts
[Level
]);
1418 Debug function used to verify if the Guard page is well set or not.
1420 @param[in] BaseAddress Address of memory to check.
1421 @param[in] NumberOfPages Size of memory in pages.
1423 @return TRUE The head Guard and tail Guard are both well set.
1424 @return FALSE The head Guard and/or tail Guard are not well set.
1428 IN EFI_PHYSICAL_ADDRESS BaseAddress
,
1429 IN UINTN NumberOfPages
1434 EFI_PHYSICAL_ADDRESS Address
;
1436 if (mSmmMemoryAttribute
== NULL
) {
1441 Address
= BaseAddress
- EFI_PAGE_SIZE
;
1442 Status
= mSmmMemoryAttribute
->GetMemoryAttributes (
1443 mSmmMemoryAttribute
,
1448 if (EFI_ERROR (Status
) || (Attribute
& EFI_MEMORY_RP
) == 0) {
1449 DEBUG ((DEBUG_ERROR
, "Head Guard is not set at: %016lx (%016lX)!!!\r\n",
1450 Address
, Attribute
));
1451 DumpGuardedMemoryBitmap ();
1456 Address
= BaseAddress
+ EFI_PAGES_TO_SIZE (NumberOfPages
);
1457 Status
= mSmmMemoryAttribute
->GetMemoryAttributes (
1458 mSmmMemoryAttribute
,
1463 if (EFI_ERROR (Status
) || (Attribute
& EFI_MEMORY_RP
) == 0) {
1464 DEBUG ((DEBUG_ERROR
, "Tail Guard is not set at: %016lx (%016lX)!!!\r\n",
1465 Address
, Attribute
));
1466 DumpGuardedMemoryBitmap ();