MdeModulePkg/DxeCore: Implement heap guard feature for UEFI

This feature makes use of paging mechanism to add a hidden (not present)
page just before and after the allocated memory block. If the code tries
to access memory outside of the allocated part, page fault exception will
be triggered.

This feature is controlled by three PCDs:

    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPropertyMask
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPoolType
    gEfiMdeModulePkgTokenSpaceGuid.PcdHeapGuardPageType

BIT0 and BIT1 of PcdHeapGuardPropertyMask can be used to enable or disable
memory guard for page and pool respectively. PcdHeapGuardPoolType and/or
PcdHeapGuardPageType are used to enable or disable guard for specific type
of memory. For example, we can turn on guard only for EfiBootServicesData
and EfiRuntimeServicesData by setting the PCD with value 0x50.

Pool memory is not ususally integer multiple of one page, and is more likely
less than a page. There's no way to monitor the overflow at both top and
bottom of pool memory. BIT7 of PcdHeapGuardPropertyMask is used to control
how to position the head of pool memory so that it's easier to catch memory
overflow in memory growing direction or in decreasing direction.

Note1: Turning on heap guard, especially pool guard, will introduce too many
memory fragments. Windows 10 has a limitation in its boot loader, which
accepts at most 512 memory descriptors passed from BIOS. This will prevent
Windows 10 from booting if heap guard is enabled. The latest Linux
distribution with grub boot loader has no such issue. Normally it's not
recommended to enable this feature in production build of BIOS.

Note2: Don't enable this feature for NT32 emulation platform which doesn't
support paging.

Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Suggested-by: Ayellet Wolman <ayellet.wolman@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Jian J Wang <jian.j.wang@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Regression-tested-by: Laszlo Ersek <lersek@redhat.com>

MdeModulePkg/Core/Dxe/Mem/Imem.h

@@ -1,7 +1,7 @@
 /** @file
   Data structure and functions to allocate and free memory space.
 
-Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2017, 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
@@ -61,6 +61,7 @@ typedef struct {
   @param  PoolType               The type of memory for the new pool pages
   @param  NumberOfPages          No of pages to allocate
   @param  Alignment              Bits to align.
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
 
   @return The allocated memory, or NULL
 
@@ -69,7 +70,8 @@ VOID *
 CoreAllocatePoolPages (
   IN EFI_MEMORY_TYPE    PoolType,
   IN UINTN              NumberOfPages,
-  IN UINTN              Alignment
+  IN UINTN              Alignment,
+  IN BOOLEAN            NeedGuard
   );
 
 
@@ -95,6 +97,7 @@ CoreFreePoolPages (
 
   @param  PoolType               Type of pool to allocate
   @param  Size                   The amount of pool to allocate
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
 
   @return The allocate pool, or NULL
 
@@ -102,7 +105,8 @@ CoreFreePoolPages (
 VOID *
 CoreAllocatePoolI (
   IN EFI_MEMORY_TYPE  PoolType,
-  IN UINTN            Size
+  IN UINTN            Size,
+  IN BOOLEAN          NeedGuard
   );
 
 
@@ -145,6 +149,34 @@ CoreReleaseMemoryLock (
   VOID
   );
 
+/**
+  Allocates pages from the memory map.
+
+  @param  Type                   The type of allocation to perform
+  @param  MemoryType             The type of memory to turn the allocated pages
+                                 into
+  @param  NumberOfPages          The number of pages to allocate
+  @param  Memory                 A pointer to receive the base allocated memory
+                                 address
+  @param  NeedGuard              Flag to indicate Guard page is needed or not
+
+  @return Status. On success, Memory is filled in with the base address allocated
+  @retval EFI_INVALID_PARAMETER  Parameters violate checking rules defined in
+                                 spec.
+  @retval EFI_NOT_FOUND          Could not allocate pages match the requirement.
+  @retval EFI_OUT_OF_RESOURCES   No enough pages to allocate.
+  @retval EFI_SUCCESS            Pages successfully allocated.
+
+**/
+EFI_STATUS
+EFIAPI
+CoreInternalAllocatePages (
+  IN EFI_ALLOCATE_TYPE      Type,
+  IN EFI_MEMORY_TYPE        MemoryType,
+  IN UINTN                  NumberOfPages,
+  IN OUT EFI_PHYSICAL_ADDRESS  *Memory,
+  IN BOOLEAN                NeedGuard
+  );
 
 //
 // Internal Global data