MdeModulePkg/IntelFrameworkModulePkg FwVol:

Move the check of FV Header signature and file system to
  GetFwVolHeader() to avoid reading the whole unexpected FvHeader.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16255 6f19259b-4bc3-4df7-8a09-765794883524

IntelFrameworkModulePkg/Universal/FirmwareVolume/FwVolDxe/FwVol.c

@@ -4,7 +4,7 @@
   Layers on top of Firmware Block protocol to produce a file abstraction
   of FV based files.
 
-  Copyright (c) 2006 - 2012, 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
@@ -34,6 +34,8 @@
   @retval EFI_SUCCESS           Successfully read volume header to the allocated
                                 buffer.
   @retval EFI_ACCESS_DENIED     Read status of FV is not enabled.
+  @retval EFI_INVALID_PARAMETER The FV Header signature is not as expected or
+                                the file system could not be understood.
 **/
 EFI_STATUS
 GetFwVolHeader (
@@ -90,6 +92,22 @@ GetFwVolHeader (
                     );
   }
 
+  //
+  // Validate FV Header signature, if not as expected, continue.
+  //
+  if (TempFvh.Signature != EFI_FVH_SIGNATURE) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // Check to see that the file system is indeed formatted in a way we can
+  // understand it...
+  //
+  if ((!CompareGuid (&TempFvh.FileSystemGuid, &gEfiFirmwareFileSystem2Guid)) &&
+      (!CompareGuid (&TempFvh.FileSystemGuid, &gEfiFirmwareFileSystem3Guid))) {
+    return EFI_INVALID_PARAMETER;
+  }
+
   *FwVolHeader = AllocatePool (TempFvh.HeaderLength);
   if (*FwVolHeader == NULL) {
     return EFI_OUT_OF_RESOURCES;
@@ -669,15 +687,6 @@ FwVolDriverInit (
       continue;
     }
     ASSERT (FwVolHeader != NULL);
-    //
-    // Check to see that the file system is indeed formatted in a way we can
-    // understand it...
-    //
-    if ((!CompareGuid (&FwVolHeader->FileSystemGuid, &gEfiFirmwareFileSystem2Guid)) &&
-        (!CompareGuid (&FwVolHeader->FileSystemGuid, &gEfiFirmwareFileSystem3Guid))) {
-      FreePool (FwVolHeader);
-      continue;
-    }
     FreePool (FwVolHeader);
 
     Reinstall = FALSE;

IntelFrameworkModulePkg/Universal/FirmwareVolume/FwVolDxe/FwVolDriver.h

@@ -1,7 +1,7 @@
 /** @file
   Common defines and definitions for a FwVolDxe driver.
 
-  Copyright (c) 2006 - 2012, 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
@@ -484,6 +484,8 @@ IsValidFFSFile (
   @retval EFI_SUCCESS           Successfully read volume header to the allocated
                                 buffer.
   @retval EFI_ACCESS_DENIED     Read status of FV is not enabled.
+  @retval EFI_INVALID_PARAMETER The FV Header signature is not as expected or
+                                the file system could not be understood.
 **/
 EFI_STATUS
 GetFwVolHeader (

MdeModulePkg/Core/Dxe/DxeMain.h

@@ -2595,6 +2595,8 @@ ReadFvbData (
   @retval EFI_OUT_OF_RESOURCES  No enough buffer could be allocated.
   @retval EFI_SUCCESS           Successfully read volume header to the allocated
                                 buffer.
+  @retval EFI_INVALID_PARAMETER The FV Header signature is not as expected or
+                                the file system could not be understood.
 
 **/
 EFI_STATUS

MdeModulePkg/Core/Dxe/FwVol/FwVol.c

@@ -173,6 +173,8 @@ ReadFvbData (
   @retval EFI_OUT_OF_RESOURCES  No enough buffer could be allocated.
   @retval EFI_SUCCESS           Successfully read volume header to the allocated
                                 buffer.
+  @retval EFI_INVALID_PARAMETER The FV Header signature is not as expected or
+                                the file system could not be understood.
 
 **/
 EFI_STATUS
@@ -199,6 +201,22 @@ GetFwVolHeader (
     return Status;
   }
 
+  //
+  // Validate FV Header signature, if not as expected, continue.
+  //
+  if (TempFvh.Signature != EFI_FVH_SIGNATURE) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  //
+  // Check to see that the file system is indeed formatted in a way we can
+  // understand it...
+  //
+  if ((!CompareGuid (&TempFvh.FileSystemGuid, &gEfiFirmwareFileSystem2Guid)) &&
+      (!CompareGuid (&TempFvh.FileSystemGuid, &gEfiFirmwareFileSystem3Guid))) {
+    return EFI_INVALID_PARAMETER;
+  }
+
   //
   // Allocate a buffer for the caller
   //
@@ -658,29 +676,11 @@ NotifyFwVolBlock (
     }
     ASSERT (FwVolHeader != NULL);
 
-    //
-    // Validate FV Header signature, if not as expected, continue.
-    //
-    if (FwVolHeader->Signature != EFI_FVH_SIGNATURE) {
-      CoreFreePool (FwVolHeader);
-      continue;
-    }
-
     if (!VerifyFvHeaderChecksum (FwVolHeader)) {
       CoreFreePool (FwVolHeader);
       continue;
     }
 
-
-    //
-    // Check to see that the file system is indeed formatted in a way we can
-    // understand it...
-    //
-    if ((!CompareGuid (&FwVolHeader->FileSystemGuid, &gEfiFirmwareFileSystem2Guid)) &&
-        (!CompareGuid (&FwVolHeader->FileSystemGuid, &gEfiFirmwareFileSystem3Guid))) {
-      continue;
-    }
-
     //
     // Check if there is an FV protocol already installed in that handle
     //

MdeModulePkg/Core/Dxe/FwVol/FwVolDriver.h

@@ -405,25 +405,4 @@ IsValidFfsFile (
   IN EFI_FFS_FILE_HEADER  *FfsHeader
   );
 
-
-/**
-  given the supplied FW_VOL_BLOCK_PROTOCOL, allocate a buffer for output and
-  copy the volume header into it.
-
-  @param  Fvb                   The FW_VOL_BLOCK_PROTOCOL instance from which to
-                                read the volume header
-  @param  FwVolHeader           Pointer to pointer to allocated buffer in which
-                                the volume header is returned.
-
-  @retval EFI_OUT_OF_RESOURCES  No enough buffer could be allocated.
-  @retval EFI_SUCCESS           Successfully read volume header to the allocated
-                                buffer.
-
-**/
-EFI_STATUS
-GetFwVolHeader (
-  IN     EFI_FIRMWARE_VOLUME_BLOCK_PROTOCOL     *Fvb,
-  OUT    EFI_FIRMWARE_VOLUME_HEADER             **FwVolHeader
-  );
-
 #endif