UefiCpuPkg PiSmmCpuDxeSmm: Fixed #double fault on #page fault for IA32

When StackGuard is enabled on IA32, the #double fault exception
is reported instead of #page fault.

This issue does not exist on X64, or IA32 without StackGuard.

The fix at e4435f710cea2d2f10cd7343d545920867780086 was incomplete.

It is because AllocateCodePages() is used to allocate buffer for
GDT and TSS, the code pages will be set to RO in SetMemMapAttributes().
But IA32 Stack Guard need use task switch to switch stack that need
write GDT and TSS, so AllocateCodePages() could not be used.

This patch uses AllocatePages() instead of AllocateCodePages() to
allocate buffer for GDT and TSS if StackGuard is enabled on IA32.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>

1 files changed, 7 insertions, 57 deletions

diff --git a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c
index 3c68c97024..4c1499939b 100644
--- a/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c
+++ b/UefiCpuPkg/PiSmmCpuDxeSmm/Ia32/SmmFuncsArch.c
@@ -1,7 +1,7 @@
 /** @file

   SMM CPU misc functions for Ia32 arch specific.

   

-Copyright (c) 2015 - 2016, Intel Corporation. All rights reserved.<BR>

+Copyright (c) 2015 - 2018, Intel Corporation. All rights reserved.<BR>

 This program and the accompanying materials

 are licensed and made available under the terms and conditions of the BSD License

 which accompanies this distribution.  The full text of the license may be found at

@@ -77,7 +77,12 @@ InitGdt (
 

     GdtTssTableSize = (gcSmiGdtr.Limit + 1 + TSS_SIZE * 2 + 7) & ~7; // 8 bytes aligned

     mGdtBufferSize = GdtTssTableSize * gSmmCpuPrivate->SmmCoreEntryContext.NumberOfCpus;

-    GdtTssTables = (UINT8*)AllocateCodePages (EFI_SIZE_TO_PAGES (mGdtBufferSize));

+    //

+    // IA32 Stack Guard need use task switch to switch stack that need

+    // write GDT and TSS, so AllocateCodePages() could not be used here

+    // as code pages will be set to RO. 

+    //

+    GdtTssTables = (UINT8*)AllocatePages (EFI_SIZE_TO_PAGES (mGdtBufferSize));

     ASSERT (GdtTssTables != NULL);

     mGdtBuffer = (UINTN)GdtTssTables;

     GdtTableStepSize = GdtTssTableSize;

@@ -127,61 +132,6 @@ InitGdt (
 }

 

 /**

-  This function sets GDT/IDT buffer to be RO and XP.

-**/

-VOID

-PatchGdtIdtMap (

-  VOID

-  )

-{

-  EFI_PHYSICAL_ADDRESS       BaseAddress;

-  UINTN                      Size;

-

-  //

-  // GDT

-  //

-  DEBUG ((DEBUG_INFO, "PatchGdtIdtMap - GDT:\n"));

-

-  BaseAddress = mGdtBuffer;

-  Size = ALIGN_VALUE(mGdtBufferSize, SIZE_4KB);

-  if (!FeaturePcdGet (PcdCpuSmmStackGuard)) {

-    //

-    // Do not set RO for IA32 when stack guard feature is enabled.

-    // Stack Guard need use task switch to switch stack.

-    // It need write GDT and TSS.

-    //

-    SmmSetMemoryAttributes (

-      BaseAddress,

-      Size,

-      EFI_MEMORY_RO

-      );

-  }

-  SmmSetMemoryAttributes (

-    BaseAddress,

-    Size,

-    EFI_MEMORY_XP

-    );

-

-  //

-  // IDT

-  //

-  DEBUG ((DEBUG_INFO, "PatchGdtIdtMap - IDT:\n"));

-

-  BaseAddress = gcSmiIdtr.Base;

-  Size = ALIGN_VALUE(gcSmiIdtr.Limit + 1, SIZE_4KB);

-  SmmSetMemoryAttributes (

-    BaseAddress,

-    Size,

-    EFI_MEMORY_RO

-    );

-  SmmSetMemoryAttributes (

-    BaseAddress,

-    Size,

-    EFI_MEMORY_XP

-    );

-}

-

-/**

   Transfer AP to safe hlt-loop after it finished restore CPU features on S3 patch.

 

   @param[in] ApHltLoopCode          The address of the safe hlt-loop function.