From: qianouyang <qianouyang@6f19259b-4bc3-4df7-8a09-765794883524>
Date: Fri, 21 May 2010 09:39:26 +0000 (+0000)
Subject: Fixed the issue of that IP4driver can’t correctly reassemble the Out of Sequence... 
X-Git-Tag: edk2-stable201903~15807
X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=commitdiff_plain;h=a167ecb13fc20bf4a2a45ef9aeda976e0498bf61

Fixed the issue of that IP4driver can’t correctly reassemble the Out of Sequence Fragments.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@10537 6f19259b-4bc3-4df7-8a09-765794883524
---

diff --git a/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Input.c b/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Input.c
index 66c8f4ad6a..d888e18e4c 100644
--- a/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Input.c
+++ b/MdeModulePkg/Universal/Network/Ip4Dxe/Ip4Input.c
@@ -292,7 +292,7 @@ Ip4Reassemble (
   // check whether THIS.Start < PREV.End for overlap. If two fragments
   // overlaps, trim the overlapped part off THIS fragment.
   //
-  if ((Prev = Cur->ForwardLink) != Head) {
+  if ((Cur != Head) && ((Prev = Cur->BackLink) != Head)) {
     Fragment  = NET_LIST_USER_STRUCT (Prev, NET_BUF, List);
     Node      = IP4_GET_CLIP_INFO (Fragment);