[IPV4]: multicast API "join" issues
1) Changes IP_ADD_SOURCE_MEMBERSHIP and MCAST_JOIN_SOURCE_GROUP to ignore
EADDRINUSE errors on a "courtesy join" -- prior membership or not
is ok for these.
2) Adds "leave group" equivalence of (INCLUDE, empty) filters in the
delta-based API. Without this, mixing delta-based API calls that
end in an (INCLUDE, empty) filter would not allow a subsequent
regular IP_ADD_MEMBERSHIP. It also frees socket buffer memory that
isn't needed for both the multicast group record and source filter.
Signed-off-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c
index f8b172f..fc7c481 100644
--- a/net/ipv4/ip_sockglue.c
+++ b/net/ipv4/ip_sockglue.c
@@ -677,11 +677,11 @@
mreq.imr_address.s_addr = mreqs.imr_interface;
mreq.imr_ifindex = 0;
err = ip_mc_join_group(sk, &mreq);
- if (err)
+ if (err && err != -EADDRINUSE)
break;
omode = MCAST_INCLUDE;
add = 1;
- } else /*IP_DROP_SOURCE_MEMBERSHIP */ {
+ } else /* IP_DROP_SOURCE_MEMBERSHIP */ {
omode = MCAST_INCLUDE;
add = 0;
}
@@ -754,7 +754,7 @@
mreq.imr_address.s_addr = 0;
mreq.imr_ifindex = greqs.gsr_interface;
err = ip_mc_join_group(sk, &mreq);
- if (err)
+ if (err && err != -EADDRINUSE)
break;
greqs.gsr_interface = mreq.imr_ifindex;
omode = MCAST_INCLUDE;