[edk2] [PATCH v6 4/7] MdeModulePkg/DxeIpl: Enable paging for heap guard

[Jian J Wang]

Heap guard feature needs paging to work properly. 64-bit BIOS uses
PcdDxeIplBuildPageTables to control the page table setup. 32-bit BIOS
has to check heap guard feature to decide enabling paging or not.

Cc: Star Zeng <star.z...@intel.com>
Cc: Eric Dong <eric.d...@intel.com>
Cc: Jiewen Yao <jiewen....@intel.com>
Suggested-by: Ayellet Wolman <ayellet.wol...@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.w...@intel.com>
Reviewed-by: Jiewen Yao <jiewen....@intel.com>
Regression-tested-by: Laszlo Ersek <ler...@redhat.com>
---
 MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf         |  1 +
 MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c | 36 ++++++++++++++++++++++---
 2 files changed, 33 insertions(+), 4 deletions(-)

diff --git a/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf 
b/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
index 9d0e76a293..a1b8748432 100644
--- a/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
+++ b/MdeModulePkg/Core/DxeIplPeim/DxeIpl.inf
@@ -116,6 +116,7 @@
   gEfiMdeModulePkgTokenSpaceGuid.PcdUse1GPageTable                      ## 
SOMETIMES_CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdPteMemoryEncryptionAddressOrMask    ## 
CONSUMES
   gEfiMdeModulePkgTokenSpaceGuid.PcdNullPointerDetectionPropertyMask    ## 
CONSUMES
+  gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask               ## 
CONSUMES
 
 [Pcd.IA32,Pcd.X64,Pcd.ARM,Pcd.AARCH64]
   gEfiMdeModulePkgTokenSpaceGuid.PcdSetNxForStack               ## 
SOMETIMES_CONSUMES
diff --git a/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c 
b/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
index 96f5718444..5649265367 100644
--- a/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
+++ b/MdeModulePkg/Core/DxeIplPeim/Ia32/DxeLoadFunc.c
@@ -211,6 +211,37 @@ IsExecuteDisableBitAvailable (
   return Available;
 }
 
+/**
+  The function will check if page table should be setup or not.
+
+  @retval TRUE      Page table should be created.
+  @retval FALSE     Page table should not be created.
+
+**/
+BOOLEAN
+ToBuildPageTable (
+  VOID
+  )
+{
+  if (!IsIa32PaeSupport ()) {
+    return FALSE;
+  }
+
+  if (IsNullDetectionEnabled ()) {
+    return TRUE;
+  }
+
+  if (PcdGet8 (PcdHeapGuardPropertyMask) != 0) {
+    return TRUE;
+  }
+
+  if (PcdGetBool (PcdSetNxForStack) && IsExecuteDisableBitAvailable ()) {
+    return TRUE;
+  }
+
+  return FALSE;
+}
+
 /**
    Transfers control to DxeCore.
 
@@ -385,10 +416,7 @@ HandOffToDxeCore (
     TopOfStack = (EFI_PHYSICAL_ADDRESS) (UINTN) ALIGN_POINTER (TopOfStack, 
CPU_STACK_ALIGNMENT);
 
     PageTables = 0;
-    BuildPageTablesIa32Pae = (BOOLEAN) (IsIa32PaeSupport () &&
-                                        (IsNullDetectionEnabled () ||
-                                         (PcdGetBool (PcdSetNxForStack) &&
-                                          IsExecuteDisableBitAvailable ())));
+    BuildPageTablesIa32Pae = ToBuildPageTable ();
     if (BuildPageTablesIa32Pae) {
       PageTables = Create4GPageTablesIa32Pae (BaseOfStack, STACK_SIZE);
       if (IsExecuteDisableBitAvailable ()) {
-- 
2.14.1.windows.1

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