[PATCH v4 1/1] igmp: call ip_mc_clear_src() only when we have no users of ip_mc_list
STALE5610d
REVIEWED: 1 (0M)
From: Veaceslav Falico <hidden>
Date: 2011-05-24 09:16:06
Also in:
lkml
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
1 review trailer.
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 <redacted> Signed-off-by: Veaceslav Falico <redacted> ---
diff --git a/net/ipv4/igmp.c b/net/ipv4/igmp.c
index 1fd3d9c..57ca93a 100644
--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c@@ -1169,20 +1169,18 @@ 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)
@@ -1319,6 +1317,7 @@ 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);
@@ -1428,7 +1427,8 @@ 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); } }