diff options
Diffstat (limited to 'src/VBox/Devices/EFI/Firmware/MdeModulePkg/Core/Dxe/Mem/HeapGuard.h')
-rw-r--r-- | src/VBox/Devices/EFI/Firmware/MdeModulePkg/Core/Dxe/Mem/HeapGuard.h | 467 |
1 files changed, 467 insertions, 0 deletions
diff --git a/src/VBox/Devices/EFI/Firmware/MdeModulePkg/Core/Dxe/Mem/HeapGuard.h b/src/VBox/Devices/EFI/Firmware/MdeModulePkg/Core/Dxe/Mem/HeapGuard.h new file mode 100644 index 00000000..7ac000dc --- /dev/null +++ b/src/VBox/Devices/EFI/Firmware/MdeModulePkg/Core/Dxe/Mem/HeapGuard.h @@ -0,0 +1,467 @@ +/** @file + Data type, macros and function prototypes of heap guard feature. + +Copyright (c) 2017-2018, Intel Corporation. All rights reserved.<BR> +SPDX-License-Identifier: BSD-2-Clause-Patent + +**/ + +#ifndef _HEAPGUARD_H_ +#define _HEAPGUARD_H_ + +// +// Following macros are used to define and access the guarded memory bitmap +// table. +// +// To simplify the access and reduce the memory used for this table, the +// table is constructed in the similar way as page table structure but in +// reverse direction, i.e. from bottom growing up to top. +// +// - 1-bit tracks 1 page (4KB) +// - 1-UINT64 map entry tracks 256KB memory +// - 1K-UINT64 map table tracks 256MB memory +// - Five levels of tables can track any address of memory of 64-bit +// system, like below. +// +// 512 * 512 * 512 * 512 * 1K * 64b * 4K +// 111111111 111111111 111111111 111111111 1111111111 111111 111111111111 +// 63 54 45 36 27 17 11 0 +// 9b 9b 9b 9b 10b 6b 12b +// L0 -> L1 -> L2 -> L3 -> L4 -> bits -> page +// 1FF 1FF 1FF 1FF 3FF 3F FFF +// +// L4 table has 1K * sizeof(UINT64) = 8K (2-page), which can track 256MB +// memory. Each table of L0-L3 will be allocated when its memory address +// range is to be tracked. Only 1-page will be allocated each time. This +// can save memories used to establish this map table. +// +// For a normal configuration of system with 4G memory, two levels of tables +// can track the whole memory, because two levels (L3+L4) of map tables have +// already coverred 37-bit of memory address. And for a normal UEFI BIOS, +// less than 128M memory would be consumed during boot. That means we just +// need +// +// 1-page (L3) + 2-page (L4) +// +// memory (3 pages) to track the memory allocation works. In this case, +// there's no need to setup L0-L2 tables. +// + +// +// Each entry occupies 8B/64b. 1-page can hold 512 entries, which spans 9 +// bits in address. (512 = 1 << 9) +// +#define BYTE_LENGTH_SHIFT 3 // (8 = 1 << 3) + +#define GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT \ + (EFI_PAGE_SHIFT - BYTE_LENGTH_SHIFT) + +#define GUARDED_HEAP_MAP_TABLE_DEPTH 5 + +// Use UINT64_index + bit_index_of_UINT64 to locate the bit in may +#define GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT 6 // (64 = 1 << 6) + +#define GUARDED_HEAP_MAP_ENTRY_BITS \ + (1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT) + +#define GUARDED_HEAP_MAP_ENTRY_BYTES \ + (GUARDED_HEAP_MAP_ENTRY_BITS / 8) + +// L4 table address width: 64 - 9 * 4 - 6 - 12 = 10b +#define GUARDED_HEAP_MAP_ENTRY_SHIFT \ + (GUARDED_HEAP_MAP_ENTRY_BITS \ + - GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 4 \ + - GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT \ + - EFI_PAGE_SHIFT) + +// L4 table address mask: (1 << 10 - 1) = 0x3FF +#define GUARDED_HEAP_MAP_ENTRY_MASK \ + ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1) + +// Size of each L4 table: (1 << 10) * 8 = 8KB = 2-page +#define GUARDED_HEAP_MAP_SIZE \ + ((1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) * GUARDED_HEAP_MAP_ENTRY_BYTES) + +// Memory size tracked by one L4 table: 8KB * 8 * 4KB = 256MB +#define GUARDED_HEAP_MAP_UNIT_SIZE \ + (GUARDED_HEAP_MAP_SIZE * 8 * EFI_PAGE_SIZE) + +// L4 table entry number: 8KB / 8 = 1024 +#define GUARDED_HEAP_MAP_ENTRIES_PER_UNIT \ + (GUARDED_HEAP_MAP_SIZE / GUARDED_HEAP_MAP_ENTRY_BYTES) + +// L4 table entry indexing +#define GUARDED_HEAP_MAP_ENTRY_INDEX(Address) \ + (RShiftU64 (Address, EFI_PAGE_SHIFT \ + + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT) \ + & GUARDED_HEAP_MAP_ENTRY_MASK) + +// L4 table entry bit indexing +#define GUARDED_HEAP_MAP_ENTRY_BIT_INDEX(Address) \ + (RShiftU64 (Address, EFI_PAGE_SHIFT) \ + & ((1 << GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT) - 1)) + +// +// Total bits (pages) tracked by one L4 table (65536-bit) +// +#define GUARDED_HEAP_MAP_BITS \ + (1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT \ + + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)) + +// +// Bit indexing inside the whole L4 table (0 - 65535) +// +#define GUARDED_HEAP_MAP_BIT_INDEX(Address) \ + (RShiftU64 (Address, EFI_PAGE_SHIFT) \ + & ((1 << (GUARDED_HEAP_MAP_ENTRY_SHIFT \ + + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT)) - 1)) + +// +// Memory address bit width tracked by L4 table: 10 + 6 + 12 = 28 +// +#define GUARDED_HEAP_MAP_TABLE_SHIFT \ + (GUARDED_HEAP_MAP_ENTRY_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT \ + + EFI_PAGE_SHIFT) + +// +// Macro used to initialize the local array variable for map table traversing +// {55, 46, 37, 28, 18} +// +#define GUARDED_HEAP_MAP_TABLE_DEPTH_SHIFTS \ + { \ + GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 3, \ + GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT * 2, \ + GUARDED_HEAP_MAP_TABLE_SHIFT + GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT, \ + GUARDED_HEAP_MAP_TABLE_SHIFT, \ + EFI_PAGE_SHIFT + GUARDED_HEAP_MAP_ENTRY_BIT_SHIFT \ + } + +// +// Masks used to extract address range of each level of table +// {0x1FF, 0x1FF, 0x1FF, 0x1FF, 0x3FF} +// +#define GUARDED_HEAP_MAP_TABLE_DEPTH_MASKS \ + { \ + (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1, \ + (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1, \ + (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1, \ + (1 << GUARDED_HEAP_MAP_TABLE_ENTRY_SHIFT) - 1, \ + (1 << GUARDED_HEAP_MAP_ENTRY_SHIFT) - 1 \ + } + +// +// Memory type to guard (matching the related PCD definition) +// +#define GUARD_HEAP_TYPE_PAGE BIT0 +#define GUARD_HEAP_TYPE_POOL BIT1 +#define GUARD_HEAP_TYPE_FREED BIT4 +#define GUARD_HEAP_TYPE_ALL \ + (GUARD_HEAP_TYPE_PAGE|GUARD_HEAP_TYPE_POOL|GUARD_HEAP_TYPE_FREED) + +// +// Debug message level +// +#define HEAP_GUARD_DEBUG_LEVEL (DEBUG_POOL|DEBUG_PAGE) + +typedef struct { + UINT32 TailMark; + UINT32 HeadMark; + EFI_PHYSICAL_ADDRESS Address; + LIST_ENTRY Link; +} HEAP_GUARD_NODE; + +/** + Internal function. Converts a memory range to the specified type. + The range must exist in the memory map. + + @param Start The first address of the range Must be page + aligned. + @param NumberOfPages The number of pages to convert. + @param NewType The new type for the memory range. + + @retval EFI_INVALID_PARAMETER Invalid parameter. + @retval EFI_NOT_FOUND Could not find a descriptor cover the specified + range or convertion not allowed. + @retval EFI_SUCCESS Successfully converts the memory range to the + specified type. + +**/ +EFI_STATUS +CoreConvertPages ( + IN UINT64 Start, + IN UINT64 NumberOfPages, + IN EFI_MEMORY_TYPE NewType + ); + +/** + 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 + ); + +/** + 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 + ); + +/** + 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 + ); + +/** + 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 + ); + +/** + 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 + ); + +/** + 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 + ); + +/** + 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 + ); + +/** + 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 + ); + +/** + 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 + ); + +/** + 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 + ); + +/** + Dump the guarded memory bit map. +**/ +VOID +EFIAPI +DumpGuardedMemoryBitmap ( + VOID + ); + +/** + 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 + ); + +/** + 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 + ); + +/** + 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 + ); + +/** + Notify function used to set all Guard pages after CPU Arch Protocol installed. +**/ +VOID +HeapGuardCpuArchProtocolNotify ( + VOID + ); + +/** + 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 + ); + +/** + 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 + ); + +/** + 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 + ); + +extern BOOLEAN mOnGuarding; + +#endif |