[PATCH 1/1] MdeModulePkg/DxeIplPeim: Relocate the operation of PageMapLevel5Entry++

["Zhang, Shenglei" <shenglei.zhang@intel.com>]

PageMapLevel5Entry may be uninitialized in original code, which means
uninitialized pointer will be modified at some circumstance.
So relocate the operation of PageMapLevel5Entry++ in order to make sure
the pointer could be modified only when it is uninitialized.

Cc: Dandan Bi <dandan.bi@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Eric Dong <eric.dong@intel.com>
Signed-off-by: Shenglei Zhang <shenglei.zhang@intel.com>
---
 MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c b/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c
index b40b7e0c9813..2389f3eb485b 100644
--- a/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c
+++ b/MdeModulePkg/Core/DxeIplPeim/X64/VirtualMemory.c
@@ -764,7 +764,7 @@ CreateIdentityMappingPageTables (
 
   for ( IndexOfPml5Entries = 0
       ; IndexOfPml5Entries < NumberOfPml5EntriesNeeded
-      ; IndexOfPml5Entries++, PageMapLevel5Entry++) {
+      ; IndexOfPml5Entries++) {
     //
     // Each PML5 entry points to a page of PML4 entires.
     // So lets allocate space for them and fill them in in the IndexOfPml4Entries loop.
@@ -780,6 +780,7 @@ CreateIdentityMappingPageTables (
       PageMapLevel5Entry->Uint64 = (UINT64) (UINTN) PageMapLevel4Entry | AddressEncMask;
       PageMapLevel5Entry->Bits.ReadWrite = 1;
       PageMapLevel5Entry->Bits.Present   = 1;
+      PageMapLevel5Entry++;
     }
 
     for ( IndexOfPml4Entries = 0
-- 
2.18.0.windows.1