[PATCH v2 2/2] NetworkPkg/HttpUtilitiesDxe: fix read memory access overflow.

[Songpeng Li <songpeng.li@intel.com>]

The input param String of AsciiStrStr() requires a pointer to
 Null-terminated string, however in HttpUtilitiesParse(),
 the Buffersize before AllocateZeroPool() is equal to the size
 of TCP header, after the CopyMem(), it might not end with
 Null-terminator. It might cause memory access overflow.

Cc: Fu Siyuan <siyuan.fu@intel.com>
Cc: Wu Jiaxin <jiaxin.wu@intel.com>
Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1204
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Songpeng Li <songpeng.li@intel.com>
---
 NetworkPkg/HttpUtilitiesDxe/HttpUtilitiesProtocol.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/NetworkPkg/HttpUtilitiesDxe/HttpUtilitiesProtocol.c b/NetworkPkg/HttpUtilitiesDxe/HttpUtilitiesProtocol.c
index a9a1c7c586..b0e3e7f081 100644
--- a/NetworkPkg/HttpUtilitiesDxe/HttpUtilitiesProtocol.c
+++ b/NetworkPkg/HttpUtilitiesDxe/HttpUtilitiesProtocol.c
@@ -298,6 +298,7 @@ HttpUtilitiesParse (
   CHAR8                     *FieldName;
   CHAR8                     *FieldValue;
   UINTN                     Index;
+  UINTN                     HttpBufferSize;
 
   Status          = EFI_SUCCESS;
   TempHttpMessage = NULL;
@@ -311,12 +312,17 @@ HttpUtilitiesParse (
     return EFI_INVALID_PARAMETER;
   }
 
-  TempHttpMessage = AllocateZeroPool (HttpMessageSize);
+  //
+  // Append the http response string along with a Null-terminator.
+  //
+  HttpBufferSize = HttpMessageSize + 1;
+  TempHttpMessage = AllocatePool (HttpBufferSize);
   if (TempHttpMessage == NULL) {
     return EFI_OUT_OF_RESOURCES;
   }
 
   CopyMem (TempHttpMessage, HttpMessage, HttpMessageSize);
+  *(TempHttpMessage + HttpMessageSize) = '\0';
 
   //
   // Get header number
-- 
2.18.0.windows.1