Add logic to validate variable before use it.

[mirror_edk2.git] / MdeModulePkg / Core / DxeIplPeim / DxeLoad.c

diff --git a/MdeModulePkg/Core/DxeIplPeim/DxeLoad.c b/MdeModulePkg/Core/DxeIplPeim/DxeLoad.c
index d0baf2eb9120ee6d84680583769af094b0602029..dea627e16282afc88bb9c5bb61c6c3d7468c4346 100644 (file)
--- a/MdeModulePkg/Core/DxeIplPeim/DxeLoad.c
+++ b/MdeModulePkg/Core/DxeIplPeim/DxeLoad.c
@@ -124,6 +124,53 @@ PeimInitializeDxeIpl (
   return Status;\r
 }\r
 \r
+/**\r
+   Validate variable data for the MemoryTypeInformation. \r
+\r
+   @param MemoryData       Variable data.\r
+   @param MemoryDataSize   Variable data length.\r
+\r
+   @return TRUE            The variable data is valid.\r
+   @return FALSE           The variable data is invalid.\r
+\r
+**/\r
+BOOLEAN\r
+ValidateMemoryTypeInfoVariable (\r
+  IN EFI_MEMORY_TYPE_INFORMATION      *MemoryData,\r
+  IN UINTN                            MemoryDataSize\r
+  )\r
+{\r
+  UINTN                       Count;\r
+  UINTN                       Index;\r
+\r
+  // Check the input parameter.\r
+  if (MemoryData == NULL) {\r
+    return FALSE;\r
+  }\r
+\r
+  // Get Count\r
+  Count = MemoryDataSize / sizeof (*MemoryData);\r
+\r
+  // Check Size\r
+  if (Count * sizeof(*MemoryData) != MemoryDataSize) {\r
+    return FALSE;\r
+  }\r
+\r
+  // Check last entry type filed.\r
+  if (MemoryData[Count - 1].Type != EfiMaxMemoryType) {\r
+    return FALSE;\r
+  }\r
+\r
+  // Check the type filed.\r
+  for (Index = 0; Index < Count - 1; Index++) {\r
+    if (MemoryData[Index].Type >= EfiMaxMemoryType) {\r
+      return FALSE;\r
+    }\r
+  }\r
+\r
+  return TRUE;\r
+}\r
+\r
 /**\r
    Main entry point to last PEIM. \r
 \r
@@ -214,7 +261,7 @@ DxeLoadCore (
                          &DataSize,\r
                          &MemoryData\r
                          );\r
-    if (!EFI_ERROR (Status)) {\r
+    if (!EFI_ERROR (Status) && ValidateMemoryTypeInfoVariable(MemoryData, DataSize)) {\r
       //\r
       // Build the GUID'd HOB for DXE\r
       //\r