From 59e0b6d40cbb321a1ea39f8b48733e1b5e961df8 Mon Sep 17 00:00:00 2001
From: Thiago Macieira <thiago.macieira@intel.com>
Date: Tue, 8 Aug 2017 15:28:12 -0700
Subject: [PATCH] QNetworkInterface: complete removing pre-Vista support

Commit 2589111dc039b30350714f632222bcc565aa34b5 removed the dynamic
function search, but did not remove the offsetof checks.

Change-Id: Ibd2b5263f7de551f47fe137dbe1a1b7b7cd71934
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Kai Koehne <kai.koehne@qt.io>
Reviewed-by: Timur Pocheptsov <timur.pocheptsov@qt.io>
---
 src/network/kernel/qnetworkinterface_win.cpp | 28 +++++++++++---------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/src/network/kernel/qnetworkinterface_win.cpp b/src/network/kernel/qnetworkinterface_win.cpp
index c2efcea625..7b6bb0c27a 100644
--- a/src/network/kernel/qnetworkinterface_win.cpp
+++ b/src/network/kernel/qnetworkinterface_win.cpp
@@ -142,7 +142,7 @@ static QHash<QHostAddress, QHostAddress> ipv4Netmasks()
 
 }
 
-static QList<QNetworkInterfacePrivate *> interfaceListingWinXP()
+static QList<QNetworkInterfacePrivate *> interfaceListing()
 {
     QList<QNetworkInterfacePrivate *> interfaces;
     IP_ADAPTER_ADDRESSES staticBuf[2]; // 2 is arbitrary
@@ -171,11 +171,18 @@ static QList<QNetworkInterfacePrivate *> interfaceListingWinXP()
 
     // iterate over the list and add the entries to our listing
     for (PIP_ADAPTER_ADDRESSES ptr = pAdapter; ptr; ptr = ptr->Next) {
+        // the structure grows over time, so let's make sure the fields
+        // introduced in Windows Vista are present (Luid is the furthest
+        // field we access from IP_ADAPTER_ADDRESSES_LH)
+        Q_ASSERT(ptr->Length >= offsetof(IP_ADAPTER_ADDRESSES, Luid));
+        Q_ASSERT(ptr->Length >= offsetof(IP_ADAPTER_ADDRESSES, Ipv6IfIndex));
+        Q_ASSERT(ptr->Length >= offsetof(IP_ADAPTER_ADDRESSES, FirstPrefix));
+
         QNetworkInterfacePrivate *iface = new QNetworkInterfacePrivate;
         interfaces << iface;
 
         iface->index = 0;
-        if (ptr->Length >= offsetof(IP_ADAPTER_ADDRESSES, Ipv6IfIndex) && ptr->Ipv6IfIndex != 0)
+        if (ptr->Ipv6IfIndex != 0)
             iface->index = ptr->Ipv6IfIndex;
         else if (ptr->IfIndex != 0)
             iface->index = ptr->IfIndex;
@@ -188,13 +195,11 @@ static QList<QNetworkInterfacePrivate *> interfaceListingWinXP()
         if (ptr->IfType == IF_TYPE_PPP)
             iface->flags |= QNetworkInterface::IsPointToPoint;
 
-        if (ptr->Length >= offsetof(IP_ADAPTER_ADDRESSES, Luid)) {
-            // use ConvertInterfaceLuidToNameW because that returns a friendlier name, though not
-            // as friendly as FriendlyName below
-            WCHAR buf[IF_MAX_STRING_SIZE + 1];
-            if (ConvertInterfaceLuidToNameW(&ptr->Luid, buf, sizeof(buf)/sizeof(buf[0])) == NO_ERROR)
-                iface->name = QString::fromWCharArray(buf);
-        }
+        // use ConvertInterfaceLuidToNameW because that returns a friendlier name, though not
+        // as "friendly" as FriendlyName below
+        WCHAR buf[IF_MAX_STRING_SIZE + 1];
+        if (ConvertInterfaceLuidToNameW(&ptr->Luid, buf, sizeof(buf)/sizeof(buf[0])) == NO_ERROR)
+            iface->name = QString::fromWCharArray(buf);
         if (iface->name.isEmpty())
             iface->name = QString::fromLocal8Bit(ptr->AdapterName);
 
@@ -213,8 +218,7 @@ static QList<QNetworkInterfacePrivate *> interfaceListingWinXP()
         // the iteration at the last Prefix entry and assume that it applies to all addresses
         // from that point on.
         PIP_ADAPTER_PREFIX pprefix = 0;
-        if (ptr->Length >= offsetof(IP_ADAPTER_ADDRESSES, FirstPrefix))
-            pprefix = ptr->FirstPrefix;
+        pprefix = ptr->FirstPrefix;
         for (PIP_ADAPTER_UNICAST_ADDRESS addr = ptr->FirstUnicastAddress; addr; addr = addr->Next) {
             QNetworkAddressEntry entry;
             entry.setIp(addressFromSockaddr(addr->Address.lpSockaddr));
@@ -240,7 +244,7 @@ static QList<QNetworkInterfacePrivate *> interfaceListingWinXP()
 
 QList<QNetworkInterfacePrivate *> QNetworkInterfaceManager::scan()
 {
-    return interfaceListingWinXP();
+    return interfaceListing();
 }
 
 QString QHostInfo::localDomainName()