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UefiCpuPkg/PiSmmCpuDxeSmm: Add paging protection.

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PiSmmCpuDxeSmm consumes SmmAttributesTable and setup page table:
1) Code region is marked as read-only and Data region is non-executable,
if the PE image is 4K aligned.
2) Important data structure is set to RO, such as GDT/IDT.
3) SmmSaveState is set to non-executable,
and SmmEntrypoint is set to read-only.
4) If static page is supported, page table is read-only.

We use page table to protect other components, and itself.

If we use dynamic paging, we can still provide *partial* protection.
And hope page table is not modified by other components.

The XD enabling code is moved to SmiEntry to let NX take effect.

Cc: Jeff Fan <jeff.fan@intel.com>
Cc: Feng Tian <feng.tian@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jiewen Yao <jiewen.yao@intel.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jeff Fan <jeff.fan@intel.com>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>
This commit is contained in:
Jiewen Yao
2016-10-23 23:19:52 +08:00
parent 28b020b5de
commit 717fb60443
25 changed files with 2042 additions and 775 deletions
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28
UefiCpuPkg/PiSmmCpuDxeSmm/X64/SmmFuncsArch.c
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@@ -14,6 +14,30 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#include "PiSmmCpuDxeSmm.h"
EFI_PHYSICAL_ADDRESS mGdtBuffer;
UINTN mGdtBufferSize;
/**
Initialize IDT for SMM Stack Guard.
**/
VOID
EFIAPI
InitializeIDTSmmStackGuard (
VOID
)
{
IA32_IDT_GATE_DESCRIPTOR *IdtGate;
//
// If SMM Stack Guard feature is enabled, set the IST field of
// the interrupt gate for Page Fault Exception to be 1
//
IdtGate = (IA32_IDT_GATE_DESCRIPTOR *)gcSmiIdtr.Base;
IdtGate += EXCEPT_IA32_PAGE_FAULT;
IdtGate->Bits.Reserved_0 = 1;
}
/**
Initialize Gdt for all processors.
@@ -41,8 +65,10 @@ InitGdt (
// on each SMI entry.
//
GdtTssTableSize = (gcSmiGdtr.Limit + 1 + TSS_SIZE + 7) & ~7; // 8 bytes aligned
GdtTssTables = (UINT8*)AllocatePages (EFI_SIZE_TO_PAGES (GdtTssTableSize * gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus));
mGdtBufferSize = GdtTssTableSize * gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus;
GdtTssTables = (UINT8*)AllocateCodePages (EFI_SIZE_TO_PAGES (mGdtBufferSize));
ASSERT (GdtTssTables != NULL);
mGdtBuffer = (UINTN)GdtTssTables;
GdtTableStepSize = GdtTssTableSize;
for (Index = 0; Index < gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus; Index++) {