[PATCH] MdeModulePkg/DxeCore: ignore PdbPointer if ImageAddress == 0

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

The memory protection code may be invoked to unprotect a driver when
DxeCore has not completed loading yet, in which case ImageAddress may
still be zero. So ignore the PdbPointer in this case, to prevent
PeCoffLoaderGetPdbPointer() from ASSERT()ing on a NULL value.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 MdeModulePkg/Core/Dxe/Misc/MemoryProtection.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/MdeModulePkg/Core/Dxe/Misc/MemoryProtection.c b/MdeModulePkg/Core/Dxe/Misc/MemoryProtection.c
index 7689c794a8ad..6ecbb311a8c3 100644
--- a/MdeModulePkg/Core/Dxe/Misc/MemoryProtection.c
+++ b/MdeModulePkg/Core/Dxe/Misc/MemoryProtection.c
@@ -462,9 +462,12 @@ ProtectUefiImageCommon (
 
   ImageAddress = LoadedImage->ImageBase;
 
-  PdbPointer = PeCoffLoaderGetPdbPointer ((VOID*) (UINTN) ImageAddress);
-  if (PdbPointer != NULL) {
-    DEBUG ((DEBUG_VERBOSE, "  Image - %a\n", PdbPointer));
+  PdbPointer = NULL;
+  if (ImageAddress != 0) {
+    PdbPointer = PeCoffLoaderGetPdbPointer ((VOID*) (UINTN) ImageAddress);
+    if (PdbPointer != NULL) {
+      DEBUG ((DEBUG_VERBOSE, "  Image - %a\n", PdbPointer));
+    }
   }
 
   //
-- 
2.7.4