[PATCH v2 2/6] MdeModulePkg/UdfDxe: ASSERT for false positives of NULL ptr deref

[Hao Wu <hao.a.wu@intel.com>]

This commit adds ASSERTs to address false positive reports of NULL
pointer dereference issues raised from static analysis with regard to
function ReadDirectoryEntry().

Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
Reviewed-by: Star Zeng <star.zeng@intel.com>
---
 MdeModulePkg/Universal/Disk/UdfDxe/File.c                 | 9 +++++++++
 MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c | 9 +++++++++
 2 files changed, 18 insertions(+)

diff --git a/MdeModulePkg/Universal/Disk/UdfDxe/File.c b/MdeModulePkg/Universal/Disk/UdfDxe/File.c
index 6f07bf2066..2249f4ea0e 100644
--- a/MdeModulePkg/Universal/Disk/UdfDxe/File.c
+++ b/MdeModulePkg/Universal/Disk/UdfDxe/File.c
@@ -408,6 +408,15 @@ UdfRead (
 
         goto Done;
       }
+      //
+      // After calling function ReadDirectoryEntry(), if 'NewFileIdentifierDesc'
+      // is NULL, then the 'Status' must be EFI_OUT_OF_RESOURCES. Hence, if the
+      // code reaches here, 'NewFileIdentifierDesc' must be not NULL.
+      //
+      // The ASSERT here is for addressing a false positive NULL pointer
+      // dereference issue raised from static analysis.
+      //
+      ASSERT (NewFileIdentifierDesc != NULL);
 
       if (!IS_FID_PARENT_FILE (NewFileIdentifierDesc)) {
         break;
diff --git a/MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c b/MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c
index 638f31bd82..8b58cc9eb1 100644
--- a/MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c
+++ b/MdeModulePkg/Universal/Disk/UdfDxe/FileSystemOperations.c
@@ -1404,6 +1404,15 @@ InternalFindFile (
 
       break;
     }
+    //
+    // After calling function ReadDirectoryEntry(), if 'FileIdentifierDesc' is
+    // NULL, then the 'Status' must be EFI_OUT_OF_RESOURCES. Hence, if the code
+    // reaches here, 'FileIdentifierDesc' must be not NULL.
+    //
+    // The ASSERT here is for addressing a false positive NULL pointer
+    // dereference issue raised from static analysis.
+    //
+    ASSERT (FileIdentifierDesc != NULL);
 
     if (FileIdentifierDesc->FileCharacteristics & PARENT_FILE) {
       //
-- 
2.12.0.windows.1