From: Wang Fan <fan.wang@intel.com>
Date: Wed, 3 Jan 2018 02:39:46 +0000 (+0800)
Subject: MdeModulePkg: Add error handling when IP address is Class E
X-Git-Tag: edk2-stable201903~2679
X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=commitdiff_plain;h=0ba795d21ad0df72ee3a12667d30ed7c64125b9c

MdeModulePkg: Add error handling when IP address is Class E

The Dhcp4.TransmitReceive() API should be able to use at any time according
to UEFI spec. While in classless addressing network, the netmask must be
explicitly provided together with the station address.
But if the DHCP instance haven't be configured with a valid netmask, we need
compute it according to the classful addressing rule. In such case, if the
user configures with class E IP address, ASSERT will happen, we need to handle
this case and return error status code.

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>
Reviewed-by: Jiaxin Wu <jiaxin.wu@intel.com>
---

diff --git a/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Impl.c b/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Impl.c
index aad667483a..9e496ef027 100644
--- a/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Impl.c
+++ b/MdeModulePkg/Universal/Network/Dhcp4Dxe/Dhcp4Impl.c
@@ -1,7 +1,7 @@
 /** @file
   This file implement the EFI_DHCP4_PROTOCOL interface.
 
-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
@@ -1186,8 +1186,10 @@ EfiDhcp4Build (
   @param[in] UdpIo      The UdpIo being created.
   @param[in] Context    Dhcp4 instance.
 
-  @retval EFI_SUCCESS   UdpIo is configured successfully.
-  @retval other         Other error occurs.
+  @retval EFI_SUCCESS              UdpIo is configured successfully.
+  @retval EFI_INVALID_PARAMETER    Class E IP address is not supported or other parameters
+                                   are not valid.
+  @retval other                    Other error occurs.
 **/
 EFI_STATUS
 EFIAPI
@@ -1229,7 +1231,14 @@ Dhcp4InstanceConfigUdpIo (
     // compute it according to the classful addressing rule.
     //
     Class = NetGetIpClass (ClientAddr);
+    //
+    //  Class E IP address is not supported here!
+    //
     ASSERT (Class < IP4_ADDR_CLASSE);
+    if (Class >= IP4_ADDR_CLASSE) {
+      return EFI_INVALID_PARAMETER;
+    }
+    
     SubnetMask = gIp4AllMasks[Class << 3];
   } else {
     SubnetMask = DhcpSb->Netmask;