net: igmp: fix source address check for IGMPv3 reports

[pandora-kernel.git] / net / ipv4 / igmp.c

diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 0a35f08..96ad44a 100644 (file)
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -89,6 +89,7 @@
 #include <linux/if_arp.h>
 #include <linux/rtnetlink.h>
 #include <linux/times.h>
+#include <linux/byteorder/generic.h>
 
 #include <net/net_namespace.h>
 #include <net/arp.h>
@@ -299,6 +300,23 @@ igmp_scount(struct ip_mc_list *pmc, int type, int gdeleted, int sdeleted)
        return scount;
 }
 
+/* source address selection per RFC 3376 section 4.2.13 */
+static __be32 igmpv3_get_srcaddr(struct net_device *dev,
+                                const struct flowi4 *fl4)
+{
+       struct in_device *in_dev = __in_dev_get_rcu(dev);
+
+       if (!in_dev)
+               return htonl(INADDR_ANY);
+
+       for_ifa(in_dev) {
+               if (fl4->saddr == ifa->ifa_local)
+                       return fl4->saddr;
+       } endfor_ifa(in_dev);
+
+       return htonl(INADDR_ANY);
+}
+
 static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
 {
        struct sk_buff *skb;
@@ -345,7 +363,7 @@ static struct sk_buff *igmpv3_newpack(struct net_device *dev, unsigned int mtu)
        pip->frag_off = htons(IP_DF);
        pip->ttl      = 1;
        pip->daddr    = fl4.daddr;
-       pip->saddr    = fl4.saddr;
+       pip->saddr    = igmpv3_get_srcaddr(dev, &fl4);
        pip->protocol = IPPROTO_IGMP;
        pip->tot_len  = 0;      /* filled in later */
        ip_select_ident(skb, NULL);