[Patch 1/2] MdeModulePkg: Fixed two issues when error occurs in Mtftp4Start.

[Wang Fan <fan.wang@intel.com>]

* This function sets returned status as token status and signal token
  when error occurs, and it results token status not compliance with
  spec definition. This patch fixed this issue.
* This function restore Tpl twice when Mtftp4WrqStart() returns an
  error, this patch fixed this issue.

Cc: Jiaxin Wu <jiaxin.wu@intel.com>
Cc: Ye Ting <ting.ye@intel.com>
Cc: Fu Siyuan <siyuan.fu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Wang Fan <fan.wang@intel.com>
---
 .../Universal/Network/Mtftp4Dxe/Mtftp4Impl.c         | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/MdeModulePkg/Universal/Network/Mtftp4Dxe/Mtftp4Impl.c b/MdeModulePkg/Universal/Network/Mtftp4Dxe/Mtftp4Impl.c
index 54384e1..f5f9e6d 100644
--- a/MdeModulePkg/Universal/Network/Mtftp4Dxe/Mtftp4Impl.c
+++ b/MdeModulePkg/Universal/Network/Mtftp4Dxe/Mtftp4Impl.c
@@ -1,10 +1,10 @@
 /** @file
   Interface routine for Mtftp4.
   
 (C) Copyright 2014 Hewlett-Packard Development Company, L.P.<BR>
-Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2018, 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
 http://opensource.org/licenses/bsd-license.php<BR>
 
@@ -407,31 +407,33 @@ Mtftp4Start (
   if (EFI_ERROR (Status)) {
     gBS->RestoreTPL (OldTpl);
     return Status;
   }
 
+  if ((Token->OverrideData != NULL) && !Mtftp4OverrideValid (Instance, Token->OverrideData)) {
+    Status = EFI_INVALID_PARAMETER;
+    gBS->RestoreTPL (OldTpl);
+    return Status;
+  }
+
   //
   // Set the Operation now to prevent the application start other
   // operations.
   //
   Instance->Operation = Operation;
   Override            = Token->OverrideData;
 
-  if ((Override != NULL) && !Mtftp4OverrideValid (Instance, Override)) {
-    Status = EFI_INVALID_PARAMETER;
-    goto ON_ERROR;
-  }
-
   if (Token->OptionCount != 0) {
     Status = Mtftp4ParseOption (
                Token->OptionList,
                Token->OptionCount,
                TRUE,
                &Instance->RequestOption
                );
 
     if (EFI_ERROR (Status)) {
+      Status = EFI_DEVICE_ERROR;
       goto ON_ERROR;
     }
   }
 
   //
@@ -482,10 +484,11 @@ Mtftp4Start (
   // Config the unicast UDP child to send initial request
   //
   Status = Mtftp4ConfigUnicastPort (Instance->UnicastPort, Instance);
 
   if (EFI_ERROR (Status)) {
+    Status = EFI_DEVICE_ERROR;
     goto ON_ERROR;
   }
 
   //
   // Set initial status.
@@ -499,17 +502,17 @@ Mtftp4Start (
     Status = Mtftp4WrqStart (Instance, Operation);
   } else {
     Status = Mtftp4RrqStart (Instance, Operation);
   }
 
-  gBS->RestoreTPL (OldTpl);
-
   if (EFI_ERROR (Status)) {
+    Status = EFI_DEVICE_ERROR;
     goto ON_ERROR;
   }
 
   if (Token->Event != NULL) {
+    gBS->RestoreTPL (OldTpl);
     return EFI_SUCCESS;
   }
 
   //
   // Return immediately for asynchronous operation or poll the
@@ -517,10 +520,11 @@ Mtftp4Start (
   //
   while (Token->Status == EFI_NOT_READY) {
     This->Poll (This);
   }
 
+  gBS->RestoreTPL (OldTpl);
   return Token->Status;
 
 ON_ERROR:
   Mtftp4CleanOperation (Instance, Status);
   gBS->RestoreTPL (OldTpl);
-- 
1.9.5.msysgit.1