From e04e0cb98e2fc119918ee4dc8039dbc6df33b881 Mon Sep 17 00:00:00 2001
From: goldsimon <goldsimon>
Date: Sun, 14 Feb 2010 20:20:28 +0000
Subject: [PATCH] Fixed bug #28877 (Duplicate ARP gratuitous packet with
 LWIP_NETIF_LINK_CALLBACK set on) by only sending if both link- and
 admin-status of a netif are up

---
 CHANGELOG        |  5 +++++
 src/core/netif.c | 18 ++++++++++--------
 2 files changed, 15 insertions(+), 8 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG
index 0ea3660b..27f86da1 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -131,6 +131,11 @@ HISTORY
 
   ++ Bugfixes:
 
+  2010-02-14: Simon Goldschmidt
+  * netif.c: Fixed bug #28877 (Duplicate ARP gratuitous packet with
+    LWIP_NETIF_LINK_CALLBACK set on) by only sending if both link- and
+    admin-status of a netif are up
+
   2010-02-14: Simon Goldschmidt
   * opt.h: Disable ETHARP_TRUST_IP_MAC by default since it slows down packet
     reception and is not really necessary
diff --git a/src/core/netif.c b/src/core/netif.c
index a7359bb4..de1959e0 100644
--- a/src/core/netif.c
+++ b/src/core/netif.c
@@ -452,19 +452,21 @@ void netif_set_up(struct netif *netif)
 
     NETIF_STATUS_CALLBACK(netif);
 
+    if (netif->flags & NETIF_FLAG_LINK_UP) {
 #if LWIP_ARP
-    /* For Ethernet network interfaces, we would like to send a "gratuitous ARP" */ 
-    if (netif->flags & NETIF_FLAG_ETHARP) {
-      etharp_gratuitous(netif);
-    }
+      /* For Ethernet network interfaces, we would like to send a "gratuitous ARP" */ 
+      if (netif->flags & (NETIF_FLAG_ETHARP)) {
+        etharp_gratuitous(netif);
+      }
 #endif /* LWIP_ARP */
 
 #if LWIP_IGMP
-    /* resend IGMP memberships */
-    if (netif->flags & NETIF_FLAG_IGMP) {
-      igmp_report_groups( netif);
-    }
+      /* resend IGMP memberships */
+      if (netif->flags & NETIF_FLAG_IGMP) {
+        igmp_report_groups( netif);
+      }
 #endif /* LWIP_IGMP */
+    }
   }
 }