GLOBAL_REMOVE_IF_UNREFERENCED UINTN mLevelMask[GUARDED_HEAP_MAP_TABLE_DEPTH]\r
= GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS;\r
\r
+//\r
+// Used for promoting freed but not used pages.\r
+//\r
+GLOBAL_REMOVE_IF_UNREFERENCED EFI_PHYSICAL_ADDRESS mLastPromotedPage = BASE_4GB;\r
+\r
/**\r
Set corresponding bits in bitmap table to 1 according to the address.\r
\r
\r
@return An integer containing the guarded memory bitmap.\r
**/\r
-UINTN\r
+UINT64\r
GetGuardedMemoryBits (\r
IN EFI_PHYSICAL_ADDRESS Address,\r
IN UINTN NumberOfPages\r
{\r
UINT64 *BitMap;\r
UINTN Bits;\r
- UINTN Result;\r
+ UINT64 Result;\r
UINTN Shift;\r
UINTN BitsToUnitEnd;\r
\r
/**\r
Check to see if the heap guard is enabled for page and/or pool allocation.\r
\r
+ @param[in] GuardType Specify the sub-type(s) of Heap Guard.\r
+\r
@return TRUE/FALSE.\r
**/\r
BOOLEAN\r
IsHeapGuardEnabled (\r
- VOID\r
+ UINT8 GuardType\r
)\r
{\r
- return IsMemoryTypeToGuard (EfiMaxMemoryType, AllocateAnyPages,\r
- GUARD_HEAP_TYPE_POOL|GUARD_HEAP_TYPE_PAGE);\r
+ return IsMemoryTypeToGuard (EfiMaxMemoryType, AllocateAnyPages, GuardType);\r
}\r
\r
/**\r
}\r
}\r
\r
+/**\r
+ Find the address of top-most guarded free page.\r
+\r
+ @param[out] Address Start address of top-most guarded free page.\r
+\r
+ @return VOID.\r
+**/\r
+VOID\r
+GetLastGuardedFreePageAddress (\r
+ OUT EFI_PHYSICAL_ADDRESS *Address\r
+ )\r
+{\r
+ EFI_PHYSICAL_ADDRESS AddressGranularity;\r
+ EFI_PHYSICAL_ADDRESS BaseAddress;\r
+ UINTN Level;\r
+ UINT64 Map;\r
+ INTN Index;\r
+\r
+ ASSERT (mMapLevel >= 1);\r
+\r
+ BaseAddress = 0;\r
+ Map = mGuardedMemoryMap;\r
+ for (Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;\r
+ Level < GUARDED_HEAP_MAP_TABLE_DEPTH;\r
+ ++Level) {\r
+ AddressGranularity = LShiftU64 (1, mLevelShift[Level]);\r
+\r
+ //\r
+ // Find the non-NULL entry at largest index.\r
+ //\r
+ for (Index = (INTN)mLevelMask[Level]; Index >= 0 ; --Index) {\r
+ if (((UINT64 *)(UINTN)Map)[Index] != 0) {\r
+ BaseAddress += MultU64x32 (AddressGranularity, (UINT32)Index);\r
+ Map = ((UINT64 *)(UINTN)Map)[Index];\r
+ break;\r
+ }\r
+ }\r
+ }\r
+\r
+ //\r
+ // Find the non-zero MSB then get the page address.\r
+ //\r
+ while (Map != 0) {\r
+ Map = RShiftU64 (Map, 1);\r
+ BaseAddress += EFI_PAGES_TO_SIZE (1);\r
+ }\r
+\r
+ *Address = BaseAddress;\r
+}\r
+\r
+/**\r
+ Record freed pages.\r
+\r
+ @param[in] BaseAddress Base address of just freed pages.\r
+ @param[in] Pages Number of freed pages.\r
+\r
+ @return VOID.\r
+**/\r
+VOID\r
+MarkFreedPages (\r
+ IN EFI_PHYSICAL_ADDRESS BaseAddress,\r
+ IN UINTN Pages\r
+ )\r
+{\r
+ SetGuardedMemoryBits (BaseAddress, Pages);\r
+}\r
+\r
+/**\r
+ Record freed pages as well as mark them as not-present.\r
+\r
+ @param[in] BaseAddress Base address of just freed pages.\r
+ @param[in] Pages Number of freed pages.\r
+\r
+ @return VOID.\r
+**/\r
+VOID\r
+EFIAPI\r
+GuardFreedPages (\r
+ IN EFI_PHYSICAL_ADDRESS BaseAddress,\r
+ IN UINTN Pages\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+\r
+ //\r
+ // Legacy memory lower than 1MB might be accessed with no allocation. Leave\r
+ // them alone.\r
+ //\r
+ if (BaseAddress < BASE_1MB) {\r
+ return;\r
+ }\r
+\r
+ MarkFreedPages (BaseAddress, Pages);\r
+ if (gCpu != NULL) {\r
+ //\r
+ // Set flag to make sure allocating memory without GUARD for page table\r
+ // operation; otherwise infinite loops could be caused.\r
+ //\r
+ mOnGuarding = TRUE;\r
+ //\r
+ // Note: This might overwrite other attributes needed by other features,\r
+ // such as NX memory protection.\r
+ //\r
+ Status = gCpu->SetMemoryAttributes (\r
+ gCpu,\r
+ BaseAddress,\r
+ EFI_PAGES_TO_SIZE (Pages),\r
+ EFI_MEMORY_RP\r
+ );\r
+ //\r
+ // Normally we should ASSERT the returned Status. But there might be memory\r
+ // alloc/free involved in SetMemoryAttributes(), which might fail this\r
+ // calling. It's rare case so it's OK to let a few tiny holes be not-guarded.\r
+ //\r
+ if (EFI_ERROR (Status)) {\r
+ DEBUG ((DEBUG_WARN, "Failed to guard freed pages: %p (%lu)\n", BaseAddress, (UINT64)Pages));\r
+ }\r
+ mOnGuarding = FALSE;\r
+ }\r
+}\r
+\r
+/**\r
+ Record freed pages as well as mark them as not-present, if enabled.\r
+\r
+ @param[in] BaseAddress Base address of just freed pages.\r
+ @param[in] Pages Number of freed pages.\r
+\r
+ @return VOID.\r
+**/\r
+VOID\r
+EFIAPI\r
+GuardFreedPagesChecked (\r
+ IN EFI_PHYSICAL_ADDRESS BaseAddress,\r
+ IN UINTN Pages\r
+ )\r
+{\r
+ if (IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED)) {\r
+ GuardFreedPages (BaseAddress, Pages);\r
+ }\r
+}\r
+\r
+/**\r
+ Mark all pages freed before CPU Arch Protocol as not-present.\r
+\r
+**/\r
+VOID\r
+GuardAllFreedPages (\r
+ VOID\r
+ )\r
+{\r
+ UINTN Entries[GUARDED_HEAP_MAP_TABLE_DEPTH];\r
+ UINTN Shifts[GUARDED_HEAP_MAP_TABLE_DEPTH];\r
+ UINTN Indices[GUARDED_HEAP_MAP_TABLE_DEPTH];\r
+ UINT64 Tables[GUARDED_HEAP_MAP_TABLE_DEPTH];\r
+ UINT64 Addresses[GUARDED_HEAP_MAP_TABLE_DEPTH];\r
+ UINT64 TableEntry;\r
+ UINT64 Address;\r
+ UINT64 GuardPage;\r
+ INTN Level;\r
+ UINTN BitIndex;\r
+ UINTN GuardPageNumber;\r
+\r
+ if (mGuardedMemoryMap == 0 ||\r
+ mMapLevel == 0 ||\r
+ mMapLevel > GUARDED_HEAP_MAP_TABLE_DEPTH) {\r
+ return;\r
+ }\r
+\r
+ CopyMem (Entries, mLevelMask, sizeof (Entries));\r
+ CopyMem (Shifts, mLevelShift, sizeof (Shifts));\r
+\r
+ SetMem (Tables, sizeof(Tables), 0);\r
+ SetMem (Addresses, sizeof(Addresses), 0);\r
+ SetMem (Indices, sizeof(Indices), 0);\r
+\r
+ Level = GUARDED_HEAP_MAP_TABLE_DEPTH - mMapLevel;\r
+ Tables[Level] = mGuardedMemoryMap;\r
+ Address = 0;\r
+ GuardPage = (UINT64)-1;\r
+ GuardPageNumber = 0;\r
+\r
+ while (TRUE) {\r
+ if (Indices[Level] > Entries[Level]) {\r
+ Tables[Level] = 0;\r
+ Level -= 1;\r
+ } else {\r
+ TableEntry = ((UINT64 *)(UINTN)(Tables[Level]))[Indices[Level]];\r
+ Address = Addresses[Level];\r
+\r
+ if (Level < GUARDED_HEAP_MAP_TABLE_DEPTH - 1) {\r
+ Level += 1;\r
+ Tables[Level] = TableEntry;\r
+ Addresses[Level] = Address;\r
+ Indices[Level] = 0;\r
+\r
+ continue;\r
+ } else {\r
+ BitIndex = 1;\r
+ while (BitIndex != 0) {\r
+ if ((TableEntry & BitIndex) != 0) {\r
+ if (GuardPage == (UINT64)-1) {\r
+ GuardPage = Address;\r
+ }\r
+ ++GuardPageNumber;\r
+ } else if (GuardPageNumber > 0) {\r
+ GuardFreedPages (GuardPage, GuardPageNumber);\r
+ GuardPageNumber = 0;\r
+ GuardPage = (UINT64)-1;\r
+ }\r
+\r
+ if (TableEntry == 0) {\r
+ break;\r
+ }\r
+\r
+ Address += EFI_PAGES_TO_SIZE (1);\r
+ BitIndex = LShiftU64 (BitIndex, 1);\r
+ }\r
+ }\r
+ }\r
+\r
+ if (Level < (GUARDED_HEAP_MAP_TABLE_DEPTH - (INTN)mMapLevel)) {\r
+ break;\r
+ }\r
+\r
+ Indices[Level] += 1;\r
+ Address = (Level == 0) ? 0 : Addresses[Level - 1];\r
+ Addresses[Level] = Address | LShiftU64 (Indices[Level], Shifts[Level]);\r
+\r
+ }\r
+\r
+ //\r
+ // Update the maximum address of freed page which can be used for memory\r
+ // promotion upon out-of-memory-space.\r
+ //\r
+ GetLastGuardedFreePageAddress (&Address);\r
+ if (Address != 0) {\r
+ mLastPromotedPage = Address;\r
+ }\r
+}\r
+\r
+/**\r
+ This function checks to see if the given memory map descriptor in a memory map\r
+ can be merged with any guarded free pages.\r
+\r
+ @param MemoryMapEntry A pointer to a descriptor in MemoryMap.\r
+ @param MaxAddress Maximum address to stop the merge.\r
+\r
+ @return VOID\r
+\r
+**/\r
+VOID\r
+MergeGuardPages (\r
+ IN EFI_MEMORY_DESCRIPTOR *MemoryMapEntry,\r
+ IN EFI_PHYSICAL_ADDRESS MaxAddress\r
+ )\r
+{\r
+ EFI_PHYSICAL_ADDRESS EndAddress;\r
+ UINT64 Bitmap;\r
+ INTN Pages;\r
+\r
+ if (!IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED) ||\r
+ MemoryMapEntry->Type >= EfiMemoryMappedIO) {\r
+ return;\r
+ }\r
+\r
+ Bitmap = 0;\r
+ Pages = EFI_SIZE_TO_PAGES (MaxAddress - MemoryMapEntry->PhysicalStart);\r
+ Pages -= MemoryMapEntry->NumberOfPages;\r
+ while (Pages > 0) {\r
+ if (Bitmap == 0) {\r
+ EndAddress = MemoryMapEntry->PhysicalStart +\r
+ EFI_PAGES_TO_SIZE (MemoryMapEntry->NumberOfPages);\r
+ Bitmap = GetGuardedMemoryBits (EndAddress, GUARDED_HEAP_MAP_ENTRY_BITS);\r
+ }\r
+\r
+ if ((Bitmap & 1) == 0) {\r
+ break;\r
+ }\r
+\r
+ Pages--;\r
+ MemoryMapEntry->NumberOfPages++;\r
+ Bitmap = RShiftU64 (Bitmap, 1);\r
+ }\r
+}\r
+\r
+/**\r
+ Put part (at most 64 pages a time) guarded free pages back to free page pool.\r
+\r
+ Freed memory guard is used to detect Use-After-Free (UAF) memory issue, which\r
+ makes use of 'Used then throw away' way to detect any illegal access to freed\r
+ memory. The thrown-away memory will be marked as not-present so that any access\r
+ to those memory (after free) will be caught by page-fault exception.\r
+\r
+ The problem is that this will consume lots of memory space. Once no memory\r
+ left in pool to allocate, we have to restore part of the freed pages to their\r
+ normal function. Otherwise the whole system will stop functioning.\r
+\r
+ @param StartAddress Start address of promoted memory.\r
+ @param EndAddress End address of promoted memory.\r
+\r
+ @return TRUE Succeeded to promote memory.\r
+ @return FALSE No free memory found.\r
+\r
+**/\r
+BOOLEAN\r
+PromoteGuardedFreePages (\r
+ OUT EFI_PHYSICAL_ADDRESS *StartAddress,\r
+ OUT EFI_PHYSICAL_ADDRESS *EndAddress\r
+ )\r
+{\r
+ EFI_STATUS Status;\r
+ UINTN AvailablePages;\r
+ UINT64 Bitmap;\r
+ EFI_PHYSICAL_ADDRESS Start;\r
+\r
+ if (!IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED)) {\r
+ return FALSE;\r
+ }\r
+\r
+ //\r
+ // Similar to memory allocation service, always search the freed pages in\r
+ // descending direction.\r
+ //\r
+ Start = mLastPromotedPage;\r
+ AvailablePages = 0;\r
+ while (AvailablePages == 0) {\r
+ Start -= EFI_PAGES_TO_SIZE (GUARDED_HEAP_MAP_ENTRY_BITS);\r
+ //\r
+ // If the address wraps around, try the really freed pages at top.\r
+ //\r
+ if (Start > mLastPromotedPage) {\r
+ GetLastGuardedFreePageAddress (&Start);\r
+ ASSERT (Start != 0);\r
+ Start -= EFI_PAGES_TO_SIZE (GUARDED_HEAP_MAP_ENTRY_BITS);\r
+ }\r
+\r
+ Bitmap = GetGuardedMemoryBits (Start, GUARDED_HEAP_MAP_ENTRY_BITS);\r
+ while (Bitmap > 0) {\r
+ if ((Bitmap & 1) != 0) {\r
+ ++AvailablePages;\r
+ } else if (AvailablePages == 0) {\r
+ Start += EFI_PAGES_TO_SIZE (1);\r
+ } else {\r
+ break;\r
+ }\r
+\r
+ Bitmap = RShiftU64 (Bitmap, 1);\r
+ }\r
+ }\r
+\r
+ if (AvailablePages) {\r
+ DEBUG ((DEBUG_INFO, "Promoted pages: %lX (%lx)\r\n", Start, (UINT64)AvailablePages));\r
+ ClearGuardedMemoryBits (Start, AvailablePages);\r
+\r
+ if (gCpu != NULL) {\r
+ //\r
+ // Set flag to make sure allocating memory without GUARD for page table\r
+ // operation; otherwise infinite loops could be caused.\r
+ //\r
+ mOnGuarding = TRUE;\r
+ Status = gCpu->SetMemoryAttributes (gCpu, Start, EFI_PAGES_TO_SIZE(AvailablePages), 0);\r
+ ASSERT_EFI_ERROR (Status);\r
+ mOnGuarding = FALSE;\r
+ }\r
+\r
+ mLastPromotedPage = Start;\r
+ *StartAddress = Start;\r
+ *EndAddress = Start + EFI_PAGES_TO_SIZE (AvailablePages) - 1;\r
+ return TRUE;\r
+ }\r
+\r
+ return FALSE;\r
+}\r
+\r
/**\r
Notify function used to set all Guard pages before CPU Arch Protocol installed.\r
**/\r
)\r
{\r
ASSERT (gCpu != NULL);\r
- SetAllGuardPages ();\r
+\r
+ if (IsHeapGuardEnabled (GUARD_HEAP_TYPE_PAGE|GUARD_HEAP_TYPE_POOL) &&\r
+ IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED)) {\r
+ DEBUG ((DEBUG_ERROR, "Heap guard and freed memory guard cannot be enabled at the same time.\n"));\r
+ CpuDeadLoop ();\r
+ }\r
+\r
+ if (IsHeapGuardEnabled (GUARD_HEAP_TYPE_PAGE|GUARD_HEAP_TYPE_POOL)) {\r
+ SetAllGuardPages ();\r
+ }\r
+\r
+ if (IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED)) {\r
+ GuardAllFreedPages ();\r
+ }\r
}\r
\r
/**\r
CHAR8 *Ruler1;\r
CHAR8 *Ruler2;\r
\r
+ if (!IsHeapGuardEnabled (GUARD_HEAP_TYPE_ALL)) {\r
+ return;\r
+ }\r
+\r
if (mGuardedMemoryMap == 0 ||\r
mMapLevel == 0 ||\r
mMapLevel > GUARDED_HEAP_MAP_TABLE_DEPTH) {\r
/** @file\r
Data type, macros and function prototypes of heap guard feature.\r
\r
-Copyright (c) 2017, Intel Corporation. All rights reserved.<BR>\r
+Copyright (c) 2017-2018, Intel Corporation. All rights reserved.<BR>\r
This program and the accompanying materials\r
are licensed and made available under the terms and conditions of the BSD License\r
which accompanies this distribution. The full text of the license may be found at\r
//\r
#define GUARD_HEAP_TYPE_PAGE BIT0\r
#define GUARD_HEAP_TYPE_POOL BIT1\r
+#define GUARD_HEAP_TYPE_FREED BIT4\r
+#define GUARD_HEAP_TYPE_ALL \\r
+ (GUARD_HEAP_TYPE_PAGE|GUARD_HEAP_TYPE_POOL|GUARD_HEAP_TYPE_FREED)\r
\r
//\r
// Debug message level\r
/**\r
Check to see if the heap guard is enabled for page and/or pool allocation.\r
\r
+ @param[in] GuardType Specify the sub-type(s) of Heap Guard.\r
+\r
@return TRUE/FALSE.\r
**/\r
BOOLEAN\r
IsHeapGuardEnabled (\r
- VOID\r
+ UINT8 GuardType\r
);\r
\r
/**\r
VOID\r
);\r
\r
+/**\r
+ This function checks to see if the given memory map descriptor in a memory map\r
+ can be merged with any guarded free pages.\r
+\r
+ @param MemoryMapEntry A pointer to a descriptor in MemoryMap.\r
+ @param MaxAddress Maximum address to stop the merge.\r
+\r
+ @return VOID\r
+\r
+**/\r
+VOID\r
+MergeGuardPages (\r
+ IN EFI_MEMORY_DESCRIPTOR *MemoryMapEntry,\r
+ IN EFI_PHYSICAL_ADDRESS MaxAddress\r
+ );\r
+\r
+/**\r
+ Record freed pages as well as mark them as not-present, if enabled.\r
+\r
+ @param[in] BaseAddress Base address of just freed pages.\r
+ @param[in] Pages Number of freed pages.\r
+\r
+ @return VOID.\r
+**/\r
+VOID\r
+EFIAPI\r
+GuardFreedPagesChecked (\r
+ IN EFI_PHYSICAL_ADDRESS BaseAddress,\r
+ IN UINTN Pages\r
+ );\r
+\r
+/**\r
+ Put part (at most 64 pages a time) guarded free pages back to free page pool.\r
+\r
+ Freed memory guard is used to detect Use-After-Free (UAF) memory issue, which\r
+ makes use of 'Used then throw away' way to detect any illegal access to freed\r
+ memory. The thrown-away memory will be marked as not-present so that any access\r
+ to those memory (after free) will be caught by page-fault exception.\r
+\r
+ The problem is that this will consume lots of memory space. Once no memory\r
+ left in pool to allocate, we have to restore part of the freed pages to their\r
+ normal function. Otherwise the whole system will stop functioning.\r
+\r
+ @param StartAddress Start address of promoted memory.\r
+ @param EndAddress End address of promoted memory.\r
+\r
+ @return TRUE Succeeded to promote memory.\r
+ @return FALSE No free memory found.\r
+\r
+**/\r
+BOOLEAN\r
+PromoteGuardedFreePages (\r
+ OUT EFI_PHYSICAL_ADDRESS *StartAddress,\r
+ OUT EFI_PHYSICAL_ADDRESS *EndAddress\r
+ );\r
+\r
extern BOOLEAN mOnGuarding;\r
\r
#endif\r
/** @file\r
UEFI Memory pool management functions.\r
\r
-Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>\r
+Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>\r
This program and the accompanying materials\r
are licensed and made available under the terms and conditions of the BSD License\r
which accompanies this distribution. The full text of the license may be found at\r
} POOL_FREE;\r
\r
\r
-#define POOL_HEAD_SIGNATURE SIGNATURE_32('p','h','d','0')\r
+#define POOL_HEAD_SIGNATURE SIGNATURE_32('p','h','d','0')\r
+#define POOLPAGE_HEAD_SIGNATURE SIGNATURE_32('p','h','d','1')\r
typedef struct {\r
UINT32 Signature;\r
UINT32 Reserved;\r
UINTN NoPages;\r
UINTN Granularity;\r
BOOLEAN HasPoolTail;\r
+ BOOLEAN PageAsPool;\r
\r
ASSERT_LOCKED (&mPoolMemoryLock);\r
\r
\r
HasPoolTail = !(NeedGuard &&\r
((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));\r
+ PageAsPool = (IsHeapGuardEnabled (GUARD_HEAP_TYPE_FREED) && !mOnGuarding);\r
\r
//\r
// Adjusting the Size to be of proper alignment so that\r
// If allocation is over max size, just allocate pages for the request\r
// (slow)\r
//\r
- if (Index >= SIZE_TO_LIST (Granularity) || NeedGuard) {\r
+ if (Index >= SIZE_TO_LIST (Granularity) || NeedGuard || PageAsPool) {\r
if (!HasPoolTail) {\r
Size -= sizeof (POOL_TAIL);\r
}\r
//\r
// If we have a pool buffer, fill in the header & tail info\r
//\r
- Head->Signature = POOL_HEAD_SIGNATURE;\r
+ Head->Signature = (PageAsPool) ? POOLPAGE_HEAD_SIGNATURE : POOL_HEAD_SIGNATURE;\r
Head->Size = Size;\r
Head->Type = (EFI_MEMORY_TYPE) PoolType;\r
Buffer = Head->Data;\r
CoreFreePoolPages (Memory, NoPages);\r
CoreReleaseMemoryLock ();\r
\r
+ GuardFreedPagesChecked (Memory, NoPages);\r
ApplyMemoryProtectionPolicy (PoolType, EfiConventionalMemory,\r
(EFI_PHYSICAL_ADDRESS)(UINTN)Memory, EFI_PAGES_TO_SIZE (NoPages));\r
}\r
UINTN Granularity;\r
BOOLEAN IsGuarded;\r
BOOLEAN HasPoolTail;\r
+ BOOLEAN PageAsPool;\r
\r
ASSERT(Buffer != NULL);\r
//\r
// Get the head & tail of the pool entry\r
//\r
- Head = CR (Buffer, POOL_HEAD, Data, POOL_HEAD_SIGNATURE);\r
+ Head = BASE_CR (Buffer, POOL_HEAD, Data);\r
ASSERT(Head != NULL);\r
\r
- if (Head->Signature != POOL_HEAD_SIGNATURE) {\r
+ if (Head->Signature != POOL_HEAD_SIGNATURE &&\r
+ Head->Signature != POOLPAGE_HEAD_SIGNATURE) {\r
+ ASSERT (Head->Signature == POOL_HEAD_SIGNATURE ||\r
+ Head->Signature == POOLPAGE_HEAD_SIGNATURE);\r
return EFI_INVALID_PARAMETER;\r
}\r
\r
IsMemoryGuarded ((EFI_PHYSICAL_ADDRESS)(UINTN)Head);\r
HasPoolTail = !(IsGuarded &&\r
((PcdGet8 (PcdHeapGuardPropertyMask) & BIT7) == 0));\r
+ PageAsPool = (Head->Signature == POOLPAGE_HEAD_SIGNATURE);\r
\r
if (HasPoolTail) {\r
Tail = HEAD_TO_TAIL (Head);\r
//\r
// If it's not on the list, it must be pool pages\r
//\r
- if (Index >= SIZE_TO_LIST (Granularity) || IsGuarded) {\r
+ if (Index >= SIZE_TO_LIST (Granularity) || IsGuarded || PageAsPool) {\r
\r
//\r
// Return the memory pages back to free memory\r
projects / mirror_edk2.git / commitdiff