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MdeModulePkg/PiSmmCore: fix #PF caused by freeing read-only memory

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SMM core will add a HEADER before each allocated pool memory and clean
up this header once it's freed. If a block of allocated pool is marked
as read-only after allocation (EfiRuntimeServicesCode type of pool in
SMM will always be marked as read-only), #PF exception will be triggered
during memory pool freeing.

Normally EfiRuntimeServicesCode type of pool should not be freed in the
real world. But some test suites will actually do memory free for all
types of memory for the purpose of functionality and conformance test.
So this issue should be fixed anyway.

Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
(cherry picked from commit a2f32ef6ff)
This commit is contained in:
Jian J Wang
2018-03-15 14:19:00 +08:00
committed by Star Zeng
parent 6a46ff8910
commit db82ec1d2f
1 changed files with 22 additions and 0 deletions
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22
MdeModulePkg/Core/PiSmmCore/HeapGuard.c
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@ -941,6 +941,7 @@ AdjustMemoryF (
EFI_PHYSICAL_ADDRESS MemoryToTest;
UINTN PagesToFree;
UINT64 GuardBitmap;
UINT64 Attributes;
if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) {
return;
@ -949,6 +950,27 @@ AdjustMemoryF (
Start = *Memory;
PagesToFree = *NumberOfPages;
//
// In case the memory to free is marked as read-only (e.g. EfiRuntimeServicesCode).
//
if (mSmmMemoryAttribute != NULL) {
Attributes = 0;
mSmmMemoryAttribute->GetMemoryAttributes (
mSmmMemoryAttribute,
Start,
EFI_PAGES_TO_SIZE (PagesToFree),
&Attributes
);
if ((Attributes & EFI_MEMORY_RO) != 0) {
mSmmMemoryAttribute->ClearMemoryAttributes (
mSmmMemoryAttribute,
Start,
EFI_PAGES_TO_SIZE (PagesToFree),
EFI_MEMORY_RO
);
}
}
//
// Head Guard must be one page before, if any.
//