Improve robustness when scanning PCI Option ROM.

Signed-off-by: rsun3
Reviewed-by: geekboy15a


git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13095 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 11 insertions, 3 deletions

diff --git a/DuetPkg/PciRootBridgeNoEnumerationDxe/X64/PcatIo.c b/DuetPkg/PciRootBridgeNoEnumerationDxe/X64/PcatIo.c
index 5320f560d9..1e4c218032 100644
--- a/DuetPkg/PciRootBridgeNoEnumerationDxe/X64/PcatIo.c
+++ b/DuetPkg/PciRootBridgeNoEnumerationDxe/X64/PcatIo.c
@@ -1,6 +1,6 @@
 /*++

 

-Copyright (c) 2005 - 2006, Intel Corporation. All rights reserved.<BR>

+Copyright (c) 2005 - 2012, 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        

@@ -436,8 +436,10 @@ CheckForRom (
 

           Pcir.ImageLength = 0;

 

-          if (EfiRomHeader.Signature == 0xaa55) {

-

+          if (EfiRomHeader.Signature == PCI_EXPANSION_ROM_HEADER_SIGNATURE &&

+              EfiRomHeader.PcirOffset != 0 &&

+              (EfiRomHeader.PcirOffset & 3) == 0 &&

+              RomBarSize + EfiRomHeader.PcirOffset + sizeof (PCI_DATA_STRUCTURE) <= MaxRomSize) {

             ZeroMem (&Pcir, sizeof(Pcir));

             IoDev->Mem.Read (

               IoDev, 

@@ -447,6 +449,12 @@ CheckForRom (
               &Pcir

               );

 

+            if (Pcir.Signature != PCI_DATA_STRUCTURE_SIGNATURE) {

+              break;

+            }

+            if (RomBarSize + Pcir.ImageLength * 512 > MaxRomSize) {

+              break;

+            }

             if ((Pcir.Indicator & 0x80) == 0x00) {

               LastImage = FALSE;

             }