ShellPkg: Add NULL pointer check.

Add pointer check to avoid NULL pointer dereferenced.

Cc: Jaben Carsey <jaben.carsey@intel.com>
Cc: Tapan Shah <tapandshah@hpe.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Qiu Shumin <shumin.qiu@intel.com>
Reviewed-by: Tapan Shah <tapandshah@hpe.com>

diff --git a/ShellPkg/Library/UefiHandleParsingLib/UefiHandleParsingLib.c b/ShellPkg/Library/UefiHandleParsingLib/UefiHandleParsingLib.c
index 58f1814b8723fa13176dad74784949e7e9a783bf..a81d1f208a2761f4560c35c10feb1352ffa4b4bd 100644 (file)
--- a/ShellPkg/Library/UefiHandleParsingLib/UefiHandleParsingLib.c
+++ b/ShellPkg/Library/UefiHandleParsingLib/UefiHandleParsingLib.c
@@ -301,14 +301,26 @@ GraphicsOutputProtocolDumpInformation(
 \r
   SHELL_FREE_NON_NULL (Temp);
   
-  Temp = HiiGetString (mHandleParsingHiiHandle, STRING_TOKEN (STR_GOP_RES_LIST_MAIN), NULL);
+  Temp = HiiGetString (mHandleParsingHiiHandle, STRING_TOKEN (STR_GOP_RES_LIST_MAIN), NULL);\r
+  if (Temp == NULL) {\r
+    SHELL_FREE_NON_NULL (RetVal);\r
+    goto EXIT;\r
+  }\r
 
   TempRetVal = CatSPrint (RetVal, Temp);
-  SHELL_FREE_NON_NULL (RetVal);
+  SHELL_FREE_NON_NULL (RetVal);\r
+  if (TempRetVal == NULL) {\r
+    goto EXIT;\r
+  }\r
   RetVal = TempRetVal;
   SHELL_FREE_NON_NULL (Temp);
 
-  Temp = HiiGetString (mHandleParsingHiiHandle, STRING_TOKEN (STR_GOP_RES_LIST_ENTRY), NULL);
+  Temp = HiiGetString (mHandleParsingHiiHandle, STRING_TOKEN (STR_GOP_RES_LIST_ENTRY), NULL);\r
+  if (Temp == NULL) {\r
+    SHELL_FREE_NON_NULL (RetVal);\r
+    goto EXIT;\r
+  }\r
+\r
 
   for (Mode = 0; Mode < GraphicsOutput->Mode->MaxMode; Mode++) {
     Status = GraphicsOutput->QueryMode (
@@ -334,6 +346,8 @@ GraphicsOutputProtocolDumpInformation(
     RetVal = TempRetVal;
   }
 
+\r
+EXIT:\r
   SHELL_FREE_NON_NULL(Temp);\r
   SHELL_FREE_NON_NULL(Fmt);\r
 \r