MdeModulePkg/Dhcp4Dxe: Remove unnecessary NULL pointer check.

v3: Add the instance token check.

v2: The DHCP Instance might be destroyed in PxeDhcpDone. So,
we need safe-delete.

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1469

Since the value of Instance is retrieved from the list Entry,
it can't be the NULL pointer, so just remove the unnecessary
check.

Cc: Ye Ting <ting.ye@intel.com>
Cc: Fu Siyuan <siyuan.fu@intel.com>
Cc: Wu Hao A <hao.a.wu@intel.com>
Cc: Gao Liming <liming.gao@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Wu Jiaxin <jiaxin.wu@intel.com>
Reviewed-by: Wu Hao A <hao.a.wu@intel.com>

diff --git a/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Io.c b/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Io.c
index 98a22a77b4473992c8993653a55c433c9a96727e..360365ecc3ad51a5b7339611e5f1b8f8b3327b3d 100644 (file)
--- a/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Io.c
+++ b/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Io.c
@@ -1,7 +1,7 @@
 /** @file\r
   EFI DHCP protocol implementation.\r
 \r
-Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.<BR>\r
+Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>\r
 This program and the accompanying materials\r
 are licensed and made available under the terms and conditions of the BSD License\r
 which accompanies this distribution.  The full text of the license may be found at\r
@@ -1648,12 +1648,9 @@ ON_EXIT:
   //\r
   NET_LIST_FOR_EACH_SAFE (Entry, Next, &DhcpSb->Children) {\r
     Instance = NET_LIST_USER_STRUCT (Entry, DHCP_PROTOCOL, Link);\r
-\r
-    if ((Instance != NULL) && (Instance->Token != NULL)) {\r
-      Instance->Timeout--;\r
-      if (Instance->Timeout == 0) {\r
-        PxeDhcpDone (Instance);\r
-      }\r
+    Instance->Timeout--;\r
+    if (Instance->Timeout == 0 && Instance->Token != NULL) {\r
+      PxeDhcpDone (Instance);\r
     }\r
   }\r
 \r