igmp: call ip_mc_clear_src() only when we have no users of ip_mc_list

In igmp_group_dropped() we call ip_mc_clear_src(), which resets the number
of source filters per mulitcast. However, igmp_group_dropped() is also
called on NETDEV_DOWN, NETDEV_PRE_TYPE_CHANGE and NETDEV_UNREGISTER, which
means that the group might get added back on NETDEV_UP, NETDEV_REGISTER and
NETDEV_POST_TYPE_CHANGE respectively, leaving us with broken source
filters.

To fix that, we must clear the source filters only when there are no users
in the ip_mc_list, i.e. in ip_mc_dec_group() and on device destroy.

Acked-by: David L Stevens <dlstevens@us.ibm.com>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Veaceslav Falico 2011-05-23 23:15:05 +00:00 committed by David S. Miller
parent be3fc413da
commit 24cf3af3fe
1 changed files with 5 additions and 5 deletions

View File

@ -1155,20 +1155,18 @@ static void igmp_group_dropped(struct ip_mc_list *im)
if (!in_dev->dead) {
if (IGMP_V1_SEEN(in_dev))
goto done;
return;
if (IGMP_V2_SEEN(in_dev)) {
if (reporter)
igmp_send_report(in_dev, im, IGMP_HOST_LEAVE_MESSAGE);
goto done;
return;
}
/* IGMPv3 */
igmpv3_add_delrec(in_dev, im);
igmp_ifc_event(in_dev);
}
done:
#endif
ip_mc_clear_src(im);
}
static void igmp_group_added(struct ip_mc_list *im)
@ -1305,6 +1303,7 @@ void ip_mc_dec_group(struct in_device *in_dev, __be32 addr)
*ip = i->next_rcu;
in_dev->mc_count--;
igmp_group_dropped(i);
ip_mc_clear_src(i);
if (!in_dev->dead)
ip_rt_multicast_event(in_dev);
@ -1414,7 +1413,8 @@ void ip_mc_destroy_dev(struct in_device *in_dev)
in_dev->mc_list = i->next_rcu;
in_dev->mc_count--;
igmp_group_dropped(i);
/* We've dropped the groups in ip_mc_down already */
ip_mc_clear_src(i);
ip_ma_put(i);
}
}