[PATCH] 2.5.64 multicast: find interface correctly

[Ted Phelps]

Joining a multicast group (IP_ADD_MEMBERSHIP) with the imr_interface
set to INADDR_ANY binds to the loopback interface.  This differs from
the 2.4 behavior and appears to be because ip_mc_find_dev() calls
ip_route_output_key() with the interface address (0.0.0.0) rather than
the multicast address (which 2.4 kernels use).  The following patch
reverts to the linux-2.4 behavior.

Thanks,
-Ted

---8<---

--- linux-2.5.63/net/ipv4/igmp.c	2003-02-26 22:28:36.000000000 +0000
+++ linux-2.5.64/net/ipv4/igmp.c	2003-03-08 22:52:38.000000000 +0000
@@ -618,6 +618,7 @@
 		__dev_put(dev);
 	}
 
+	fl.nl_u.ip4_u.daddr = imr->imr_multiaddr.s_addr;
 	if (!dev && !ip_route_output_key(&rt, &fl)) {
 		dev = rt->u.dst.dev;
 		ip_rt_put(rt);