[Patch] SecurityPkg/Pkcs7VerifyDxe: Add format check in DB list contents

[Qin Long <qin.long@intel.com>]

Add the size check for invalid format detection in AllowedDb,
RevokedDb and TimeStampDb list contents.

Cc: Chao Zhang <chao.b.zhang@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Qin Long <qin.long@intel.com>
---
 .../Pkcs7Verify/Pkcs7VerifyDxe/Pkcs7VerifyDxe.c    | 66 ++++++++++++++++++++--
 1 file changed, 60 insertions(+), 6 deletions(-)

diff --git a/SecurityPkg/Pkcs7Verify/Pkcs7VerifyDxe/Pkcs7VerifyDxe.c b/SecurityPkg/Pkcs7Verify/Pkcs7VerifyDxe/Pkcs7VerifyDxe.c
index 07fdf552be..3776f903d4 100644
--- a/SecurityPkg/Pkcs7Verify/Pkcs7VerifyDxe/Pkcs7VerifyDxe.c
+++ b/SecurityPkg/Pkcs7Verify/Pkcs7VerifyDxe/Pkcs7VerifyDxe.c
@@ -5,7 +5,7 @@
   verify data signed using PKCS7 structure. The PKCS7 data to be verified must
   be ASN.1 (DER) encoded.
 
-Copyright (c) 2015, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2015 - 2017, 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
@@ -801,11 +801,13 @@ VerifyBuffer (
   IN OUT UINTN                    *ContentSize
   )
 {
-  EFI_STATUS  Status;
-  UINT8       *AttachedData;
-  UINTN       AttachedDataSize;
-  UINT8       *DataPtr;
-  UINTN       DataSize;
+  EFI_STATUS          Status;
+  EFI_SIGNATURE_LIST  *SigList;
+  UINTN               Index;
+  UINT8               *AttachedData;
+  UINTN               AttachedDataSize;
+  UINT8               *DataPtr;
+  UINTN               DataSize;
 
   //
   // Parameters Checking
@@ -818,6 +820,58 @@ VerifyBuffer (
   }
 
   //
+  // Check if any invalid entry format in AllowedDb list contents
+  //
+  for (Index = 0; ; Index++) {
+    SigList = (EFI_SIGNATURE_LIST *)(AllowedDb[Index]);
+
+    if (SigList == NULL) {
+      break;
+    }
+    if (SigList->SignatureListSize < sizeof (EFI_SIGNATURE_LIST) +
+                                     SigList->SignatureHeaderSize +
+                                     SigList->SignatureSize) {
+      return EFI_ABORTED;
+    }
+  }
+
+  //
+  // Check if any invalid entry format in RevokedDb list contents
+  //
+  if (RevokedDb != NULL) {
+    for (Index = 0; ; Index++) {
+      SigList = (EFI_SIGNATURE_LIST *)(RevokedDb[Index]);
+
+      if (SigList == NULL) {
+        break;
+      }
+      if (SigList->SignatureListSize < sizeof (EFI_SIGNATURE_LIST) +
+                                       SigList->SignatureHeaderSize +
+                                       SigList->SignatureSize) {
+        return EFI_ABORTED;
+      }
+    }
+  }
+
+  //
+  // Check if any invalid entry format in TimeStampDb list contents
+  //
+  if (TimeStampDb != NULL) {
+    for (Index = 0; ; Index++) {
+      SigList = (EFI_SIGNATURE_LIST *)(TimeStampDb[Index]);
+
+      if (SigList == NULL) {
+        break;
+      }
+      if (SigList->SignatureListSize < sizeof (EFI_SIGNATURE_LIST) +
+                                       SigList->SignatureHeaderSize +
+                                       SigList->SignatureSize) {
+        return EFI_ABORTED;
+      }
+    }
+  }
+
+  //
   // Try to retrieve the attached content from PKCS7 signedData
   //
   AttachedData     = NULL;
-- 
2.12.2.windows.1