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authorJian J Wang <jian.j.wang@intel.com>2018-03-15 14:19:00 +0800
committerStar Zeng <star.zeng@intel.com>2018-03-16 15:14:32 +0800
commitdb82ec1d2f3288907c7942614a58bed431f391ce (patch)
tree93b6b995e375dc663a9d2c4b6a04d65641a1dfac
parent6a46ff8910af17226a3d39a186da03d18f813a7e (diff)
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MdeModulePkg/PiSmmCore: fix #PF caused by freeing read-only memory
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 a2f32ef6ff173ef276a661520196fb04bbaec3f9)
-rw-r--r--MdeModulePkg/Core/PiSmmCore/HeapGuard.c22
1 files changed, 22 insertions, 0 deletions
diff --git a/MdeModulePkg/Core/PiSmmCore/HeapGuard.c b/MdeModulePkg/Core/PiSmmCore/HeapGuard.c
index f9657f9baa..d5556eb79c 100644
--- a/MdeModulePkg/Core/PiSmmCore/HeapGuard.c
+++ b/MdeModulePkg/Core/PiSmmCore/HeapGuard.c
@@ -941,6 +941,7 @@ AdjustMemoryF (
EFI_PHYSICAL_ADDRESS MemoryToTest;
UINTN PagesToFree;
UINT64 GuardBitmap;
+ UINT64 Attributes;
if (Memory == NULL || NumberOfPages == NULL || *NumberOfPages == 0) {
return;
@@ -950,6 +951,27 @@ AdjustMemoryF (
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.
//
// MSB-> 1 0 <-LSB