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MdeModulePkg/BootScriptExecutorDxe: remove NX attr for FfsBuffer

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If PcdDxeNxMemoryProtectionPolicy is set to enable protection for memory
of EfiReservedMemoryType, the BIOS will hang at a page fault exception
triggered by BootScriptExecutorDxe.

The root cause is that this driver will allocate memory of
EfiReservedMemoryType and relocate itself into this new memory. Since
EfiReservedMemoryType of memory is marked non-executable, re-start this
driver after relocation will cause exception. The fix is removing the NX
attribute after memory allocation.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
(cherry picked from commit 6a3094c996)
This commit is contained in:
Jian J Wang
2018-01-15 10:25:40 +08:00
committed by Star Zeng
parent 4fd863634a
commit a46544a8b0
3 changed files with 16 additions and 0 deletions
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14
MdeModulePkg/Universal/Acpi/BootScriptExecutorDxe/ScriptExecute.c
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@ -273,6 +273,7 @@ ReadyToLockEventNotify (
UINTN Pages;
EFI_PHYSICAL_ADDRESS FfsBuffer;
PE_COFF_LOADER_IMAGE_CONTEXT ImageContext;
EFI_GCD_MEMORY_SPACE_DESCRIPTOR MemDesc;
Status = gBS->LocateProtocol (&gEfiDxeSmmReadyToLockProtocolGuid, NULL, &Interface);
if (EFI_ERROR (Status)) {
@ -322,6 +323,19 @@ ReadyToLockEventNotify (
&FfsBuffer
);
ASSERT_EFI_ERROR (Status);
//
// Make sure that the buffer can be used to store code.
//
Status = gDS->GetMemorySpaceDescriptor (FfsBuffer, &MemDesc);
if (!EFI_ERROR (Status) && (MemDesc.Attributes & EFI_MEMORY_XP) != 0) {
gDS->SetMemorySpaceAttributes (
FfsBuffer,
EFI_PAGES_TO_SIZE (Pages),
MemDesc.Attributes & (~EFI_MEMORY_XP)
);
}
ImageContext.ImageAddress = (PHYSICAL_ADDRESS)(UINTN)FfsBuffer;
//
// Align buffer on section boundary