ShellPkg: Verify memory allocations without ASSERT.

signed-off-by: jcarsey
reviewed-by: geekboy15a

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12522 6f19259b-4bc3-4df7-8a09-765794883524

4 files changed, 160 insertions, 115 deletions

diff --git a/ShellPkg/Library/UefiShellLevel2CommandsLib/Cd.c b/ShellPkg/Library/UefiShellLevel2CommandsLib/Cd.c
index c753702e81..74beb093c4 100644
--- a/ShellPkg/Library/UefiShellLevel2CommandsLib/Cd.c
+++ b/ShellPkg/Library/UefiShellLevel2CommandsLib/Cd.c
@@ -96,78 +96,47 @@ ShellCommandRunCd (
       }

     } else {

       Param1Copy = CatSPrint(NULL, L"%s", Param1, NULL);

-      Param1Copy = PathCleanUpDirectories(Param1Copy);

-      if (StrCmp(Param1Copy, L".") == 0) {

-        //

-        // nothing to do... change to current directory

-        //

-      } else if (StrCmp(Param1Copy, L"..") == 0) {

-        //

-        // Change up one directory...

-        //

-        Directory = ShellGetCurrentDir(NULL);

-        if (Directory == NULL) {

-          ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_NO_CWD), gShellLevel2HiiHandle);

-          ShellStatus = SHELL_NOT_FOUND;

-        } else {

-          Drive = GetFullyQualifiedPath(Directory);

-          PathRemoveLastItem(Drive);

-        }

-        if (ShellStatus == SHELL_SUCCESS && Drive != NULL) {

+      if (Param1Copy != NULL) {

+        Param1Copy = PathCleanUpDirectories(Param1Copy);

+      }

+      if (Param1Copy != NULL) {

+        if (StrCmp(Param1Copy, L".") == 0) {

           //

-          // change directory on current drive letter

+          // nothing to do... change to current directory

           //

-          Status = gEfiShellProtocol->SetCurDir(NULL, Drive);

-          if (Status == EFI_NOT_FOUND) {

-            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_CD_NF), gShellLevel2HiiHandle);

-            ShellStatus = SHELL_NOT_FOUND;

-          }

-        }

-      } else if (StrCmp(Param1Copy, L"\\") == 0) {

-        //

-        // Move to root of current drive

-        //

-        Directory = ShellGetCurrentDir(NULL);

-        if (Directory == NULL) {

-          ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_NO_CWD), gShellLevel2HiiHandle);

-          ShellStatus = SHELL_NOT_FOUND;

-        } else {

-          Drive = GetFullyQualifiedPath(Directory);

-          while (PathRemoveLastItem(Drive)) ;

-        }

-        if (ShellStatus == SHELL_SUCCESS && Drive != NULL) {

+        } else if (StrCmp(Param1Copy, L"..") == 0) {

           //

-          // change directory on current drive letter

+          // Change up one directory...

           //

-          Status = gEfiShellProtocol->SetCurDir(NULL, Drive);

-          if (Status == EFI_NOT_FOUND) {

-            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_CD_NF), gShellLevel2HiiHandle);

+          Directory = ShellGetCurrentDir(NULL);

+          if (Directory == NULL) {

+            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_NO_CWD), gShellLevel2HiiHandle);

             ShellStatus = SHELL_NOT_FOUND;

-          }

-        }

-      } else if (StrStr(Param1Copy, L":") == NULL) {

-        if (ShellGetCurrentDir(NULL) == NULL) {

-          ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_NO_CWD), gShellLevel2HiiHandle);

-          ShellStatus = SHELL_NOT_FOUND;

-        } else {

-          ASSERT((Drive == NULL && DriveSize == 0) || (Drive != NULL));

-          Drive = StrnCatGrow(&Drive, &DriveSize, ShellGetCurrentDir(NULL), 0);

-          if (*Param1Copy == L'\\') {

-            while (PathRemoveLastItem(Drive)) ;

-            Drive = StrnCatGrow(&Drive, &DriveSize, Param1Copy+1, 0);

           } else {

-            Drive = StrnCatGrow(&Drive, &DriveSize, Param1Copy, 0);

+            Drive = GetFullyQualifiedPath(Directory);

+            PathRemoveLastItem(Drive);

           }

+          if (ShellStatus == SHELL_SUCCESS && Drive != NULL) {

+            //

+            // change directory on current drive letter

+            //

+            Status = gEfiShellProtocol->SetCurDir(NULL, Drive);

+            if (Status == EFI_NOT_FOUND) {

+              ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_CD_NF), gShellLevel2HiiHandle);

+              ShellStatus = SHELL_NOT_FOUND;

+            }

+          }

+        } else if (StrCmp(Param1Copy, L"\\") == 0) {

           //

-          // Verify that this is a valid directory

+          // Move to root of current drive

           //

-          Status = gEfiShellProtocol->OpenFileByName(Drive, &Handle, EFI_FILE_MODE_READ);

-          if (EFI_ERROR(Status)) {

-            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_DIR_NF), gShellLevel2HiiHandle, Drive);

-            ShellStatus = SHELL_NOT_FOUND;

-          } else if (EFI_ERROR(FileHandleIsDirectory(Handle))) {

-            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_NOT_DIR), gShellLevel2HiiHandle, Drive);

+          Directory = ShellGetCurrentDir(NULL);

+          if (Directory == NULL) {

+            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_NO_CWD), gShellLevel2HiiHandle);

             ShellStatus = SHELL_NOT_FOUND;

+          } else {

+            Drive = GetFullyQualifiedPath(Directory);

+            while (PathRemoveLastItem(Drive)) ;

           }

           if (ShellStatus == SHELL_SUCCESS && Drive != NULL) {

             //

@@ -179,42 +148,77 @@ ShellCommandRunCd (
               ShellStatus = SHELL_NOT_FOUND;

             }

           }

-          if (Handle != NULL) {

-            gEfiShellProtocol->CloseFile(Handle);

-            DEBUG_CODE(Handle = NULL;);

+        } else if (StrStr(Param1Copy, L":") == NULL) {

+          if (ShellGetCurrentDir(NULL) == NULL) {

+            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_NO_CWD), gShellLevel2HiiHandle);

+            ShellStatus = SHELL_NOT_FOUND;

+          } else {

+            ASSERT((Drive == NULL && DriveSize == 0) || (Drive != NULL));

+            Drive = StrnCatGrow(&Drive, &DriveSize, ShellGetCurrentDir(NULL), 0);

+            if (*Param1Copy == L'\\') {

+              while (PathRemoveLastItem(Drive)) ;

+              Drive = StrnCatGrow(&Drive, &DriveSize, Param1Copy+1, 0);

+            } else {

+              Drive = StrnCatGrow(&Drive, &DriveSize, Param1Copy, 0);

+            }

+            //

+            // Verify that this is a valid directory

+            //

+            Status = gEfiShellProtocol->OpenFileByName(Drive, &Handle, EFI_FILE_MODE_READ);

+            if (EFI_ERROR(Status)) {

+              ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_DIR_NF), gShellLevel2HiiHandle, Drive);

+              ShellStatus = SHELL_NOT_FOUND;

+            } else if (EFI_ERROR(FileHandleIsDirectory(Handle))) {

+              ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_NOT_DIR), gShellLevel2HiiHandle, Drive);

+              ShellStatus = SHELL_NOT_FOUND;

+            }

+            if (ShellStatus == SHELL_SUCCESS && Drive != NULL) {

+              //

+              // change directory on current drive letter

+              //

+              Status = gEfiShellProtocol->SetCurDir(NULL, Drive);

+              if (Status == EFI_NOT_FOUND) {

+                ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_CD_NF), gShellLevel2HiiHandle);

+                ShellStatus = SHELL_NOT_FOUND;

+              }

+            }

+            if (Handle != NULL) {

+              gEfiShellProtocol->CloseFile(Handle);

+              DEBUG_CODE(Handle = NULL;);

+            }

           }

-        }

-      } else {

-        //

-        // change directory on other drive letter

-        //

-        Drive = AllocateZeroPool(StrSize(Param1Copy));

-        if (Drive == NULL) {

-          ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_NO_MEM), gShellLevel2HiiHandle);

-          ShellStatus = SHELL_OUT_OF_RESOURCES;

         } else {

-          Drive = StrCpy(Drive, Param1Copy);

-          Path = StrStr(Drive, L":");

-          ASSERT(Path != NULL);

-          if (*(Path+1) == CHAR_NULL) {

-            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_CD_NF), gShellLevel2HiiHandle);

-            ShellStatus = SHELL_NOT_FOUND;

+          //

+          // change directory on other drive letter

+          //

+          Drive = AllocateZeroPool(StrSize(Param1Copy));

+          if (Drive == NULL) {

+            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_NO_MEM), gShellLevel2HiiHandle);

+            ShellStatus = SHELL_OUT_OF_RESOURCES;

           } else {

-            *(Path+1) = CHAR_NULL;

-            if (Path == Drive + StrLen(Drive)) {

+            Drive = StrCpy(Drive, Param1Copy);

+            Path = StrStr(Drive, L":");

+            ASSERT(Path != NULL);

+            if (*(Path+1) == CHAR_NULL) {

               ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_CD_NF), gShellLevel2HiiHandle);

               ShellStatus = SHELL_NOT_FOUND;

             } else {

-              Status = gEfiShellProtocol->SetCurDir(Drive, Path+2);

-              ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_CD_PRINT), gShellLevel2HiiHandle, ShellGetCurrentDir(Drive));

+              *(Path+1) = CHAR_NULL;

+              if (Path == Drive + StrLen(Drive)) {

+                ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_CD_NF), gShellLevel2HiiHandle);

+                ShellStatus = SHELL_NOT_FOUND;

+              } else {

+                Status = gEfiShellProtocol->SetCurDir(Drive, Path+2);

+                ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_CD_PRINT), gShellLevel2HiiHandle, ShellGetCurrentDir(Drive));

+              }

+            }

+            if (Status == EFI_NOT_FOUND) {

+              ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_CD_NF), gShellLevel2HiiHandle);

+              Status = SHELL_NOT_FOUND;

+            } else if (EFI_ERROR(Status)) {

+              ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_DIR_NF), gShellLevel2HiiHandle, Param1Copy);

+              Status = SHELL_NOT_FOUND;

             }

-          }

-          if (Status == EFI_NOT_FOUND) {

-            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_CD_NF), gShellLevel2HiiHandle);

-            Status = SHELL_NOT_FOUND;

-          } else if (EFI_ERROR(Status)) {

-            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_DIR_NF), gShellLevel2HiiHandle, Param1Copy);

-            Status = SHELL_NOT_FOUND;

           }

         }

       }

diff --git a/ShellPkg/Library/UefiShellLevel2CommandsLib/Mv.c b/ShellPkg/Library/UefiShellLevel2CommandsLib/Mv.c
index b83eede5a9..a93ef33c03 100644
--- a/ShellPkg/Library/UefiShellLevel2CommandsLib/Mv.c
+++ b/ShellPkg/Library/UefiShellLevel2CommandsLib/Mv.c
@@ -120,9 +120,10 @@ IsValidMove(
   @param[in, out] DestPathPointer  A pointer to the callee allocated final path.

   @param[in] Cwd                   A pointer to the current working directory.

 

-  @retval EFI_INVALID_PARAMETR  The DestDir could not be resolved to a location.

-  @retval EFI_INVALID_PARAMETR  The DestDir could be resolved to more than 1 location.

-  @retval EFI_SUCCESS           The operation was sucessful.

+  @retval SHELL_INVALID_PARAMETER  The DestDir could not be resolved to a location.

+  @retval SHELL_INVALID_PARAMETER  The DestDir could be resolved to more than 1 location.

+  @retval SHELL_INVALID_PARAMETER  Cwd is required and is NULL.

+  @retval SHELL_SUCCESS            The operation was sucessful.

 **/

 SHELL_STATUS

 EFIAPI

@@ -143,6 +144,9 @@ GetDestinationLocation(
   DestPath = NULL;

 

   if (StrStr(DestDir, L"\\") == DestDir) {

+    if (Cwd == NULL) {

+      return SHELL_INVALID_PARAMETER;

+    }

     DestPath = AllocateZeroPool(StrSize(Cwd));

     if (DestPath == NULL) {

       return (SHELL_OUT_OF_RESOURCES);

@@ -161,6 +165,10 @@ GetDestinationLocation(
     // Not existing... must be renaming

     //

     if ((TempLocation = StrStr(DestDir, L":")) == NULL) {

+      if (Cwd == NULL) {

+        ShellCloseFileMetaArg(&DestList);

+        return (SHELL_INVALID_PARAMETER);

+      }

       NewSize = StrSize(Cwd);

       NewSize += StrSize(DestDir);

       DestPath = AllocateZeroPool(NewSize);

diff --git a/ShellPkg/Library/UefiShellLevel2CommandsLib/TimeDate.c b/ShellPkg/Library/UefiShellLevel2CommandsLib/TimeDate.c
index 44e83ba254..aa40bbf22f 100644
--- a/ShellPkg/Library/UefiShellLevel2CommandsLib/TimeDate.c
+++ b/ShellPkg/Library/UefiShellLevel2CommandsLib/TimeDate.c
@@ -179,6 +179,7 @@ ShellCommandRunDate (
   EFI_TIME      TheTime;

   CHAR16        *ProblemParam;

   SHELL_STATUS  ShellStatus;

+  CONST CHAR16  *Param1;

 

   ShellStatus  = SHELL_SUCCESS;

   ProblemParam = NULL;

@@ -238,9 +239,14 @@ ShellCommandRunDate (
           //

           // perform level 3 operation here.

           //

-          ShellStatus = CheckAndSetDate(ShellCommandLineGetRawValue(Package, 1));

+          Param1 = ShellCommandLineGetRawValue(Package, 1);

+          if (Param1 == NULL) {

+            ShellStatus = SHELL_INVALID_PARAMETER;

+          } else {

+            ShellStatus = CheckAndSetDate(Param1);

+          }

           if (ShellStatus != SHELL_SUCCESS) {

-            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_PROBLEM), gShellLevel2HiiHandle, ShellCommandLineGetRawValue(Package, 1));

+            ShellPrintHiiEx(-1, -1, NULL, STRING_TOKEN (STR_GEN_PROBLEM), gShellLevel2HiiHandle, Param1);

             ShellStatus = SHELL_INVALID_PARAMETER;

           }

         }

diff --git a/ShellPkg/Library/UefiShellLib/UefiShellLib.c b/ShellPkg/Library/UefiShellLib/UefiShellLib.c
index 06e2386378..474aecb7ae 100644
--- a/ShellPkg/Library/UefiShellLib/UefiShellLib.c
+++ b/ShellPkg/Library/UefiShellLib/UefiShellLib.c
@@ -84,6 +84,8 @@ ShellIsDecimalDigitCharacter (
   Helper function to find ShellEnvironment2 for constructor.

 

   @param[in] ImageHandle    A copy of the calling image's handle.

+

+  @retval EFI_OUT_OF_RESOURCES    Memory allocation failed.

 **/

 EFI_STATUS

 EFIAPI

@@ -123,7 +125,9 @@ ShellFindSE2 (
     //

     if (Status == EFI_BUFFER_TOO_SMALL) {

       Buffer = (EFI_HANDLE*)AllocateZeroPool(BufferSize);

-      ASSERT(Buffer != NULL);

+      if (Buffer == NULL) {

+        return (EFI_OUT_OF_RESOURCES);

+      }

       Status = gBS->LocateHandle (ByProtocol,

                                   &gEfiShellEnvironment2Guid,

                                   NULL, // ignored for ByProtocol

@@ -1360,8 +1364,9 @@ InternalShellConvertFileListType (
     // allocate a new EFI_SHELL_FILE_INFO object

     //

     NewInfo               = AllocateZeroPool(sizeof(EFI_SHELL_FILE_INFO));

-    ASSERT(NewInfo != NULL);

     if (NewInfo == NULL) {

+      ShellCloseFileMetaArg(&(EFI_SHELL_FILE_INFO*)ListHead);

+      ListHead = NULL;

       break;

     }

 

@@ -1384,9 +1389,11 @@ InternalShellConvertFileListType (
     //

     // make sure all the memory allocations were sucessful

     //

-    ASSERT(NewInfo->FullName != NULL);

-    ASSERT(NewInfo->FileName != NULL);

-    ASSERT(NewInfo->Info     != NULL);

+    if (NULL == NewInfo->FullName || NewInfo->FileName == NULL || NewInfo->Info == NULL) {

+      ShellCloseFileMetaArg(&(EFI_SHELL_FILE_INFO*)ListHead);

+      ListHead = NULL;

+      break;

+    }

 

     //

     // Copt the strings and structure

@@ -1612,7 +1619,6 @@ ShellFindFilePath (
     Size = StrSize(Path);

     Size += StrSize(FileName);

     TestPath = AllocateZeroPool(Size);

-    ASSERT(TestPath != NULL);

     if (TestPath == NULL) {

       return (NULL);

     }

@@ -1719,7 +1725,6 @@ ShellFindFilePathEx (
   Size =  StrSize(FileName);

   Size += StrSize(FileExtension);

   TestPath = AllocateZeroPool(Size);

-  ASSERT(TestPath != NULL);

   if (TestPath == NULL) {

     return (NULL);

   }

@@ -1934,8 +1939,9 @@ InternalCommandLineParse (
   //

   *CheckPackage = (LIST_ENTRY*)AllocateZeroPool(sizeof(LIST_ENTRY));

   if (*CheckPackage == NULL) {

-    return EFI_OUT_OF_RESOURCES;

+    return (EFI_OUT_OF_RESOURCES);

   }

+

   InitializeListHead(*CheckPackage);

 

   //

@@ -1958,9 +1964,17 @@ InternalCommandLineParse (
       // this is a flag

       //

       CurrentItemPackage = AllocateZeroPool(sizeof(SHELL_PARAM_PACKAGE));

-      ASSERT(CurrentItemPackage != NULL);

+      if (CurrentItemPackage == NULL) {

+        ShellCommandLineFreeVarList(*CheckPackage);

+        *CheckPackage = NULL;

+        return (EFI_OUT_OF_RESOURCES);

+      }

       CurrentItemPackage->Name  = AllocateZeroPool(StrSize(Argv[LoopCounter]));

-      ASSERT(CurrentItemPackage->Name != NULL);

+      if (CurrentItemPackage->Name == NULL) {

+        ShellCommandLineFreeVarList(*CheckPackage);

+        *CheckPackage = NULL;

+        return (EFI_OUT_OF_RESOURCES);

+      }

       StrCpy(CurrentItemPackage->Name,  Argv[LoopCounter]);

       CurrentItemPackage->Type  = CurrentItemType;

       CurrentItemPackage->OriginalPosition = (UINTN)(-1);

@@ -2024,11 +2038,19 @@ InternalCommandLineParse (
         TempPointer++;

       }

       CurrentItemPackage = AllocateZeroPool(sizeof(SHELL_PARAM_PACKAGE));

-      ASSERT(CurrentItemPackage != NULL);

+      if (CurrentItemPackage == NULL) {

+        ShellCommandLineFreeVarList(*CheckPackage);

+        *CheckPackage = NULL;

+        return (EFI_OUT_OF_RESOURCES);

+      }

       CurrentItemPackage->Name  = NULL;

       CurrentItemPackage->Type  = TypePosition;

       CurrentItemPackage->Value = AllocateZeroPool(StrSize(TempPointer));

-      ASSERT(CurrentItemPackage->Value != NULL);

+      if (CurrentItemPackage->Value == NULL) {

+        ShellCommandLineFreeVarList(*CheckPackage);

+        *CheckPackage = NULL;

+        return (EFI_OUT_OF_RESOURCES);

+      }

       StrCpy(CurrentItemPackage->Value, TempPointer);

       CurrentItemPackage->OriginalPosition = Count++;

       InsertHeadList(*CheckPackage, &CurrentItemPackage->Link);

@@ -2038,8 +2060,9 @@ InternalCommandLineParse (
       //

       if (ProblemParam != NULL) {

         *ProblemParam = AllocateZeroPool(StrSize(Argv[LoopCounter]));

-        ASSERT(*ProblemParam != NULL);

-        StrCpy(*ProblemParam, Argv[LoopCounter]);      

+        if (*ProblemParam != NULL) {

+          StrCpy(*ProblemParam, Argv[LoopCounter]);      

+        }

       }

       ShellCommandLineFreeVarList(*CheckPackage);

       *CheckPackage = NULL;

@@ -2504,7 +2527,9 @@ ShellCopySearchAndReplace(
     Replace = StrnCatGrow(&Replace, NULL, ReplaceWith, 0);

   } else {

     Replace = AllocateZeroPool(StrSize(ReplaceWith) + 2*sizeof(CHAR16));

-    UnicodeSPrint(Replace, StrSize(ReplaceWith) + 2*sizeof(CHAR16), L"\"%s\"", ReplaceWith);

+    if (Replace != NULL) {

+      UnicodeSPrint(Replace, StrSize(ReplaceWith) + 2*sizeof(CHAR16), L"\"%s\"", ReplaceWith);

+    }

   }

   if (Replace == NULL) {

     return (EFI_OUT_OF_RESOURCES);

@@ -3092,11 +3117,9 @@ StrnCatGrow (
       NewSize += 2 * Count * sizeof(CHAR16);

     }

     *Destination = ReallocatePool(*CurrentSize, NewSize, *Destination);

-    ASSERT(*Destination != NULL);

     *CurrentSize = NewSize;

   } else {

     *Destination = AllocateZeroPool((Count+1)*sizeof(CHAR16));

-    ASSERT(*Destination != NULL);

   }

 

   //

@@ -3831,7 +3854,8 @@ ShellIsHexOrDecimalNumber (
   @param[in, out]  Ascii         Boolean value for indicating whether the file is

                                  Ascii (TRUE) or UCS2 (FALSE).

 

-  @return                       The line of text from the file.

+  @return                        The line of text from the file.

+  @retval NULL                   There was not enough memory available.

 

   @sa ShellFileHandleReadLine

 **/

@@ -3852,9 +3876,12 @@ ShellFileHandleReturnLine(
   Status = ShellFileHandleReadLine(Handle, RetVal, &Size, FALSE, Ascii);

   if (Status == EFI_BUFFER_TOO_SMALL) {

     RetVal = AllocateZeroPool(Size);

+    if (RetVal == NULL) {

+      return (NULL);

+    }

     Status = ShellFileHandleReadLine(Handle, RetVal, &Size, FALSE, Ascii);

+    

   }

-  ASSERT_EFI_ERROR(Status);

   if (EFI_ERROR(Status) && (RetVal != NULL)) {

     FreePool(RetVal);

     RetVal = NULL;