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MdeModulePkg PiSmmCore: Enhance SMM FreePool to catch buffer overflow

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This solution is equivalent to DXE core.

AllocatePool() allocates POOL_TAIL after the buffer.
This POOL_TAIL is checked at FreePool().
If the there is buffer overflow, the issue can be caught at FreePool().

This patch could also handle the eight-byte aligned allocation
requirement. The discussion related to the eight-byte aligned
allocation requirement is at
https://lists.01.org/pipermail/edk2-devel/2017-April/009995.html.

According to the PI spec (Vol 4, Section 3.2 SmmAllocatePool()):
The SmmAllocatePool() function ... All allocations are eight-byte aligned.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Hao Wu <hao.a.wu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Hao Wu <hao.a.wu@intel.com>
This commit is contained in:
Star Zeng
2017-04-19 11:12:18 +08:00
parent 95ad8f7f6a
commit 861c8dff2f
2 changed files with 61 additions and 5 deletions
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22
MdeModulePkg/Core/PiSmmCore/PiSmmCore.h
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@@ -1196,12 +1196,28 @@ extern LIST_ENTRY mSmmMemoryMap;
//
#define MAX_POOL_INDEX (MAX_POOL_SHIFT - MIN_POOL_SHIFT + 1)
#define POOL_HEAD_SIGNATURE SIGNATURE_32('p','h','d','0')
typedef struct {
UINTN Size;
BOOLEAN Available;
EFI_MEMORY_TYPE Type;
UINT32 Signature;
BOOLEAN Available;
EFI_MEMORY_TYPE Type;
UINTN Size;
} POOL_HEADER;
#define POOL_TAIL_SIGNATURE SIGNATURE_32('p','t','a','l')
typedef struct {
UINT32 Signature;
UINT32 Reserved;
UINTN Size;
} POOL_TAIL;
#define POOL_OVERHEAD (sizeof(POOL_HEADER) + sizeof(POOL_TAIL))
#define HEAD_TO_TAIL(a) \
((POOL_TAIL *) (((CHAR8 *) (a)) + (a)->Size - sizeof(POOL_TAIL)));
typedef struct {
POOL_HEADER Header;
LIST_ENTRY Link;