MdeModulePkg/SecurityPkg Variable: Add boundary check for while (IsValidVariableHeader (Variable)).

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16280 6f19259b-4bc3-4df7-8a09-765794883524

2 files changed, 42 insertions, 26 deletions

diff --git a/MdeModulePkg/Universal/Variable/Pei/Variable.c b/MdeModulePkg/Universal/Variable/Pei/Variable.c
index df0304748c..4716cc5124 100644
--- a/MdeModulePkg/Universal/Variable/Pei/Variable.c
+++ b/MdeModulePkg/Universal/Variable/Pei/Variable.c
@@ -3,7 +3,7 @@
   Implement ReadOnly Variable Services required by PEIM and install

   PEI ReadOnly Varaiable2 PPI. These services operates the non volatile storage space.

 

-Copyright (c) 2006 - 2013, Intel Corporation. All rights reserved.<BR>

+Copyright (c) 2006 - 2014, Intel Corporation. All rights reserved.<BR>

 This program and the accompanying materials

 are licensed and made available under the terms and conditions of the BSD License

 which accompanies this distribution.  The full text of the license may be found at

@@ -547,14 +547,25 @@ GetVariableHeader (
   EFI_HOB_GUID_TYPE     *GuidHob;

   UINTN                 PartialHeaderSize;

 

+  if (Variable == NULL) {

+    return FALSE;

+  }

+

    //

    // First assume variable header pointed by Variable is consecutive.

    //

   *VariableHeader = Variable;

 

-  if ((Variable != NULL) && (StoreInfo->FtwLastWriteData != NULL)) {

+  if (StoreInfo->FtwLastWriteData != NULL) {

     TargetAddress = StoreInfo->FtwLastWriteData->TargetAddress;

     SpareAddress = StoreInfo->FtwLastWriteData->SpareAddress;

+    if (((UINTN) Variable > (UINTN) SpareAddress) &&

+        (((UINTN) Variable - (UINTN) SpareAddress + (UINTN) TargetAddress) >= (UINTN) GetEndPointer (StoreInfo->VariableStoreHeader))) {

+      //

+      // Reach the end of variable store.

+      //

+      return FALSE;

+    }

     if (((UINTN) Variable < (UINTN) TargetAddress) && (((UINTN) Variable + sizeof (VARIABLE_HEADER)) > (UINTN) TargetAddress)) {

       //

       // Variable header pointed by Variable is inconsecutive,

@@ -576,6 +587,13 @@ GetVariableHeader (
         CopyMem ((UINT8 *) *VariableHeader + PartialHeaderSize, (UINT8 *) (UINTN) SpareAddress, sizeof (VARIABLE_HEADER) - PartialHeaderSize);

       }

     }

+  } else {

+    if (Variable >= GetEndPointer (StoreInfo->VariableStoreHeader)) {

+      //

+      // Reach the end of variable store.

+      //

+      return FALSE;

+    }

   }

 

   return IsValidVariableHeader (*VariableHeader);

diff --git a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
index fc7fbab5d6..c66bdbf9fd 100644
--- a/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
+++ b/MdeModulePkg/Universal/Variable/RuntimeDxe/Variable.c
@@ -190,18 +190,24 @@ UpdateVariableInfo (
 

   This code checks if variable header is valid or not.

 

-  @param Variable        Pointer to the Variable Header.

+  @param Variable           Pointer to the Variable Header.

+  @param VariableStoreEnd   Pointer to the Variable Store End.

 

-  @retval TRUE           Variable header is valid.

-  @retval FALSE          Variable header is not valid.

+  @retval TRUE              Variable header is valid.

+  @retval FALSE             Variable header is not valid.

 

 **/

 BOOLEAN

 IsValidVariableHeader (

-  IN  VARIABLE_HEADER   *Variable

+  IN  VARIABLE_HEADER       *Variable,

+  IN  VARIABLE_HEADER       *VariableStoreEnd

   )

 {

-  if (Variable == NULL || Variable->StartId != VARIABLE_DATA) {

+  if ((Variable == NULL) || (Variable >= VariableStoreEnd) || (Variable->StartId != VARIABLE_DATA)) {

+    //

+    // Variable is NULL or has reached the end of variable store,

+    // or the StartId is not correct.

+    //

     return FALSE;

   }

 

@@ -499,10 +505,6 @@ GetNextVariablePtr (
 {

   UINTN Value;

 

-  if (!IsValidVariableHeader (Variable)) {

-    return NULL;

-  }

-

   Value =  (UINTN) GetVariableDataPtr (Variable);

   Value += DataSizeOfVariable (Variable);

   Value += GET_PAD_SIZE (DataSizeOfVariable (Variable));

@@ -622,7 +624,7 @@ Reclaim (
     Variable          = GetStartPointer (VariableStoreHeader);

     MaximumBufferSize = sizeof (VARIABLE_STORE_HEADER);

 

-    while (IsValidVariableHeader (Variable)) {

+    while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader))) {

       NextVariable = GetNextVariablePtr (Variable);

       if ((Variable->State == VAR_ADDED || Variable->State == (VAR_IN_DELETED_TRANSITION & VAR_ADDED)) &&

           Variable != UpdatingVariable &&

@@ -672,7 +674,7 @@ Reclaim (
   // Reinstall all ADDED variables as long as they are not identical to Updating Variable.

   // 

   Variable = GetStartPointer (VariableStoreHeader);

-  while (IsValidVariableHeader (Variable)) {

+  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader))) {

     NextVariable = GetNextVariablePtr (Variable);

     if (Variable != UpdatingVariable && Variable->State == VAR_ADDED) {

       VariableSize = (UINTN) NextVariable - (UINTN) Variable;

@@ -691,7 +693,7 @@ Reclaim (
   // Reinstall all in delete transition variables.

   // 

   Variable = GetStartPointer (VariableStoreHeader);

-  while (IsValidVariableHeader (Variable)) {

+  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader))) {

     NextVariable = GetNextVariablePtr (Variable);

     if (Variable != UpdatingVariable && Variable != UpdatingInDeletedTransition && Variable->State == (VAR_IN_DELETED_TRANSITION & VAR_ADDED)) {

 

@@ -703,7 +705,7 @@ Reclaim (
      

       FoundAdded = FALSE;

       AddedVariable = GetStartPointer ((VARIABLE_STORE_HEADER *) ValidBuffer);

-      while (IsValidVariableHeader (AddedVariable)) {

+      while (IsValidVariableHeader (AddedVariable, GetEndPointer ((VARIABLE_STORE_HEADER *) ValidBuffer))) {

         NextAddedVariable = GetNextVariablePtr (AddedVariable);

         NameSize = NameSizeOfVariable (AddedVariable);

         if (CompareGuid (&AddedVariable->VendorGuid, &Variable->VendorGuid) &&

@@ -795,7 +797,7 @@ Reclaim (
       mVariableModuleGlobal->CommonVariableTotalSize = CommonVariableTotalSize;

     } else {

       NextVariable  = GetStartPointer ((VARIABLE_STORE_HEADER *)(UINTN)VariableBase);

-      while (IsValidVariableHeader (NextVariable)) {

+      while (IsValidVariableHeader (NextVariable, GetEndPointer ((VARIABLE_STORE_HEADER *)(UINTN)VariableBase))) {

         VariableSize = NextVariable->NameSize + NextVariable->DataSize + sizeof (VARIABLE_HEADER);

         if ((Variable->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD) == EFI_VARIABLE_HARDWARE_ERROR_RECORD) {

           mVariableModuleGlobal->HwErrVariableTotalSize += HEADER_ALIGN (VariableSize);

@@ -853,7 +855,7 @@ FindVariableEx (
   InDeletedVariable  = NULL;

 

   for ( PtrTrack->CurrPtr = PtrTrack->StartPtr

-      ; (PtrTrack->CurrPtr < PtrTrack->EndPtr) && IsValidVariableHeader (PtrTrack->CurrPtr)

+      ; IsValidVariableHeader (PtrTrack->CurrPtr, PtrTrack->EndPtr)

       ; PtrTrack->CurrPtr = GetNextVariablePtr (PtrTrack->CurrPtr)

       ) {

     if (PtrTrack->CurrPtr->State == VAR_ADDED || 

@@ -2408,10 +2410,7 @@ VariableServiceGetNextVariableName (
     //

     // Switch from Volatile to HOB, to Non-Volatile.

     //

-    while ((Variable.CurrPtr >= Variable.EndPtr) ||

-           (Variable.CurrPtr == NULL)            ||

-           !IsValidVariableHeader (Variable.CurrPtr)

-          ) {

+    while (!IsValidVariableHeader (Variable.CurrPtr, Variable.EndPtr)) {

       //

       // Find current storage index

       //

@@ -2617,8 +2616,7 @@ VariableServiceSetVariable (
     // Parse non-volatile variable data and get last variable offset.

     //

     NextVariable  = GetStartPointer ((VARIABLE_STORE_HEADER *) (UINTN) Point);

-    while ((NextVariable < GetEndPointer ((VARIABLE_STORE_HEADER *) (UINTN) Point)) 

-        && IsValidVariableHeader (NextVariable)) {

+    while (IsValidVariableHeader (NextVariable, GetEndPointer ((VARIABLE_STORE_HEADER *) (UINTN) Point))) {

       NextVariable = GetNextVariablePtr (NextVariable);

     }

     mVariableModuleGlobal->NonVolatileLastVariableOffset = (UINTN) NextVariable - (UINTN) Point;

@@ -2765,7 +2763,7 @@ VariableServiceQueryVariableInfoInternal (
   //

   // Now walk through the related variable store.

   //

-  while ((Variable < GetEndPointer (VariableStoreHeader)) && IsValidVariableHeader (Variable)) {

+  while (IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader))) {

     NextVariable = GetNextVariablePtr (Variable);

     VariableSize = (UINT64) (UINTN) NextVariable - (UINT64) (UINTN) Variable;

 

@@ -3063,7 +3061,7 @@ InitNonVolatileVariableStore (
   // Parse non-volatile variable data and get last variable offset.

   //

   NextVariable  = GetStartPointer ((VARIABLE_STORE_HEADER *)(UINTN)VariableStoreBase);

-  while (IsValidVariableHeader (NextVariable)) {

+  while (IsValidVariableHeader (NextVariable, GetEndPointer ((VARIABLE_STORE_HEADER *)(UINTN)VariableStoreBase))) {

     VariableSize = NextVariable->NameSize + NextVariable->DataSize + sizeof (VARIABLE_HEADER);

     if ((NextVariable->Attributes & (EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_HARDWARE_ERROR_RECORD)) == (EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_HARDWARE_ERROR_RECORD)) {

       mVariableModuleGlobal->HwErrVariableTotalSize += HEADER_ALIGN (VariableSize);

@@ -3109,7 +3107,7 @@ FlushHobVariableToFlash (
     //

     mVariableModuleGlobal->VariableGlobal.HobVariableBase = 0;

     for ( Variable = GetStartPointer (VariableStoreHeader)

-        ; (Variable < GetEndPointer (VariableStoreHeader) && IsValidVariableHeader (Variable))

+        ; IsValidVariableHeader (Variable, GetEndPointer (VariableStoreHeader))

         ; Variable = GetNextVariablePtr (Variable)

         ) {

       if (Variable->State != VAR_ADDED) {