From 1c8ad5bfa2be5025b0c81e3c2decd0574d453ab1 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Tue, 21 May 2013 21:52:54 +0000 Subject: bridge: use the bridge IP addr as source addr for querier Quote from Adam: "If it is believed that the use of 0.0.0.0 as the IP address is what is causing strange behaviour on other devices then is there a good reason that a bridge rather than a router shouldn't be the active querier? If not then using the bridge IP address and having the querier enabled by default may be a reasonable solution (provided that our querier obeys the election rules and shuts up if it sees a query from a lower IP address that isn't 0.0.0.0). Just because a device is the elected querier for IGMP doesn't appear to mean it is required to perform any other routing functions." And introduce a new troggle for it, as suggested by Herbert. Suggested-by: Adam Baker Cc: Herbert Xu Cc: Stephen Hemminger Cc: "David S. Miller" Cc: Adam Baker Signed-off-by: Cong Wang Acked-by: Herbert Xu Signed-off-by: David S. Miller --- net/bridge/br_multicast.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'net/bridge/br_multicast.c') diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 81f2389f78eb..247514793101 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -23,6 +23,7 @@ #include #include #include +#include #include #if IS_ENABLED(CONFIG_IPV6) #include @@ -381,7 +382,8 @@ static struct sk_buff *br_ip4_multicast_alloc_query(struct net_bridge *br, iph->frag_off = htons(IP_DF); iph->ttl = 1; iph->protocol = IPPROTO_IGMP; - iph->saddr = 0; + iph->saddr = br->multicast_query_use_ifaddr ? + inet_select_addr(br->dev, 0, RT_SCOPE_LINK) : 0; iph->daddr = htonl(INADDR_ALLHOSTS_GROUP); ((u8 *)&iph[1])[0] = IPOPT_RA; ((u8 *)&iph[1])[1] = 4; @@ -1618,6 +1620,7 @@ void br_multicast_init(struct net_bridge *br) br->multicast_router = 1; br->multicast_querier = 0; + br->multicast_query_use_ifaddr = 0; br->multicast_last_member_count = 2; br->multicast_startup_query_count = 2; -- cgit v1.2.3 From 9f00b2e7cf241fa389733d41b615efdaa2cb0f5b Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Tue, 21 May 2013 21:52:55 +0000 Subject: bridge: only expire the mdb entry when query is received Currently we arm the expire timer when the mdb entry is added, however, this causes problem when there is no querier sent out after that. So we should only arm the timer when a corresponding query is received, as suggested by Herbert. And he also mentioned "if there is no querier then group subscriptions shouldn't expire. There has to be at least one querier in the network for this thing to work. Otherwise it just degenerates into a non-snooping switch, which is OK." Cc: Herbert Xu Cc: Stephen Hemminger Cc: "David S. Miller" Cc: Adam Baker Signed-off-by: Cong Wang Acked-by: Herbert Xu Signed-off-by: David S. Miller --- net/bridge/br_multicast.c | 39 ++++++++++++--------------------------- 1 file changed, 12 insertions(+), 27 deletions(-) (limited to 'net/bridge/br_multicast.c') diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 247514793101..40bda804fbd9 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -617,8 +617,6 @@ rehash: mp->br = br; mp->addr = *group; - setup_timer(&mp->timer, br_multicast_group_expired, - (unsigned long)mp); hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]); mdb->size++; @@ -656,7 +654,6 @@ static int br_multicast_add_group(struct net_bridge *br, struct net_bridge_mdb_entry *mp; struct net_bridge_port_group *p; struct net_bridge_port_group __rcu **pp; - unsigned long now = jiffies; int err; spin_lock(&br->multicast_lock); @@ -671,7 +668,6 @@ static int br_multicast_add_group(struct net_bridge *br, if (!port) { mp->mglist = true; - mod_timer(&mp->timer, now + br->multicast_membership_interval); goto out; } @@ -679,7 +675,7 @@ static int br_multicast_add_group(struct net_bridge *br, (p = mlock_dereference(*pp, br)) != NULL; pp = &p->next) { if (p->port == port) - goto found; + goto out; if ((unsigned long)p->port < (unsigned long)port) break; } @@ -690,8 +686,6 @@ static int br_multicast_add_group(struct net_bridge *br, rcu_assign_pointer(*pp, p); br_mdb_notify(br->dev, port, group, RTM_NEWMDB); -found: - mod_timer(&p->timer, now + br->multicast_membership_interval); out: err = 0; @@ -1131,6 +1125,10 @@ static int br_ip4_multicast_query(struct net_bridge *br, if (!mp) goto out; + setup_timer(&mp->timer, br_multicast_group_expired, (unsigned long)mp); + mod_timer(&mp->timer, now + br->multicast_membership_interval); + mp->timer_armed = true; + max_delay *= br->multicast_last_member_count; if (mp->mglist && @@ -1205,6 +1203,10 @@ static int br_ip6_multicast_query(struct net_bridge *br, if (!mp) goto out; + setup_timer(&mp->timer, br_multicast_group_expired, (unsigned long)mp); + mod_timer(&mp->timer, now + br->multicast_membership_interval); + mp->timer_armed = true; + max_delay *= br->multicast_last_member_count; if (mp->mglist && (timer_pending(&mp->timer) ? @@ -1263,7 +1265,7 @@ static void br_multicast_leave_group(struct net_bridge *br, call_rcu_bh(&p->rcu, br_multicast_free_pg); br_mdb_notify(br->dev, port, group, RTM_DELMDB); - if (!mp->ports && !mp->mglist && + if (!mp->ports && !mp->mglist && mp->timer_armed && netif_running(br->dev)) mod_timer(&mp->timer, jiffies); } @@ -1275,30 +1277,12 @@ static void br_multicast_leave_group(struct net_bridge *br, br->multicast_last_member_interval; if (!port) { - if (mp->mglist && + if (mp->mglist && mp->timer_armed && (timer_pending(&mp->timer) ? time_after(mp->timer.expires, time) : try_to_del_timer_sync(&mp->timer) >= 0)) { mod_timer(&mp->timer, time); } - - goto out; - } - - for (p = mlock_dereference(mp->ports, br); - p != NULL; - p = mlock_dereference(p->next, br)) { - if (p->port != port) - continue; - - if (!hlist_unhashed(&p->mglist) && - (timer_pending(&p->timer) ? - time_after(p->timer.expires, time) : - try_to_del_timer_sync(&p->timer) >= 0)) { - mod_timer(&p->timer, time); - } - - break; } out: @@ -1674,6 +1658,7 @@ void br_multicast_stop(struct net_bridge *br) hlist_for_each_entry_safe(mp, n, &mdb->mhash[i], hlist[ver]) { del_timer(&mp->timer); + mp->timer_armed = false; call_rcu_bh(&mp->rcu, br_multicast_free_group); } } -- cgit v1.2.3 From 6b7df111ece130fa979a0c4f58e53674c1e47d3e Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Tue, 21 May 2013 21:52:56 +0000 Subject: bridge: send query as soon as leave is received Continue sending queries when leave is received if the user marks it as a querier. Cc: Herbert Xu Cc: Stephen Hemminger Cc: "David S. Miller" Cc: Adam Baker Signed-off-by: Cong Wang Acked-by: Herbert Xu Signed-off-by: David S. Miller --- net/bridge/br_multicast.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'net/bridge/br_multicast.c') diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 40bda804fbd9..37a467697967 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -1250,6 +1250,32 @@ static void br_multicast_leave_group(struct net_bridge *br, if (!mp) goto out; + if (br->multicast_querier && + !timer_pending(&br->multicast_querier_timer)) { + __br_multicast_send_query(br, port, &mp->addr); + + time = jiffies + br->multicast_last_member_count * + br->multicast_last_member_interval; + mod_timer(port ? &port->multicast_query_timer : + &br->multicast_query_timer, time); + + for (p = mlock_dereference(mp->ports, br); + p != NULL; + p = mlock_dereference(p->next, br)) { + if (p->port != port) + continue; + + if (!hlist_unhashed(&p->mglist) && + (timer_pending(&p->timer) ? + time_after(p->timer.expires, time) : + try_to_del_timer_sync(&p->timer) >= 0)) { + mod_timer(&p->timer, time); + } + + break; + } + } + if (port && (port->flags & BR_MULTICAST_FAST_LEAVE)) { struct net_bridge_port_group __rcu **pp; -- cgit v1.2.3 From 7c77602f57da3f526fa7cf7bb02c49d3397c0729 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Fri, 21 Jun 2013 15:37:25 +0800 Subject: bridge: fix a typo in comments Cc: Stephen Hemminger Cc: "David S. Miller" Signed-off-by: Cong Wang Signed-off-by: David S. Miller --- net/bridge/br_multicast.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/bridge/br_multicast.c') diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 31952a103949..81befac015e1 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -1012,7 +1012,7 @@ static int br_ip6_multicast_mld2_report(struct net_bridge *br, #endif /* - * Add port to rotuer_list + * Add port to router_list * list is maintained ordered by pointer value * and locked by br->multicast_lock and RCU */ -- cgit v1.2.3 From c7e8e8a8f7a70b343ca1e0f90a31e35ab2d16de1 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Fri, 5 Jul 2013 19:36:17 +0800 Subject: bridge: fix some kernel warning in multicast timer Several people reported the warning: "kernel BUG at kernel/timer.c:729!" and the stack trace is: #7 [ffff880214d25c10] mod_timer+501 at ffffffff8106d905 #8 [ffff880214d25c50] br_multicast_del_pg.isra.20+261 at ffffffffa0731d25 [bridge] #9 [ffff880214d25c80] br_multicast_disable_port+88 at ffffffffa0732948 [bridge] #10 [ffff880214d25cb0] br_stp_disable_port+154 at ffffffffa072bcca [bridge] #11 [ffff880214d25ce8] br_device_event+520 at ffffffffa072a4e8 [bridge] #12 [ffff880214d25d18] notifier_call_chain+76 at ffffffff8164aafc #13 [ffff880214d25d50] raw_notifier_call_chain+22 at ffffffff810858f6 #14 [ffff880214d25d60] call_netdevice_notifiers+45 at ffffffff81536aad #15 [ffff880214d25d80] dev_close_many+183 at ffffffff81536d17 #16 [ffff880214d25dc0] rollback_registered_many+168 at ffffffff81537f68 #17 [ffff880214d25de8] rollback_registered+49 at ffffffff81538101 #18 [ffff880214d25e10] unregister_netdevice_queue+72 at ffffffff815390d8 #19 [ffff880214d25e30] __tun_detach+272 at ffffffffa074c2f0 [tun] #20 [ffff880214d25e88] tun_chr_close+45 at ffffffffa074c4bd [tun] #21 [ffff880214d25ea8] __fput+225 at ffffffff8119b1f1 #22 [ffff880214d25ef0] ____fput+14 at ffffffff8119b3fe #23 [ffff880214d25f00] task_work_run+159 at ffffffff8107cf7f #24 [ffff880214d25f30] do_notify_resume+97 at ffffffff810139e1 #25 [ffff880214d25f50] int_signal+18 at ffffffff8164f292 this is due to I forgot to check if mp->timer is armed in br_multicast_del_pg(). This bug is introduced by commit 9f00b2e7cf241fa389733d41b6 (bridge: only expire the mdb entry when query is received). Same for __br_mdb_del(). Tested-by: poma Reported-by: LiYonghua <809674045@qq.com> Reported-by: Robert Hancock Cc: Herbert Xu Cc: Stephen Hemminger Cc: "David S. Miller" Signed-off-by: Cong Wang Signed-off-by: David S. Miller --- net/bridge/br_multicast.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/bridge/br_multicast.c') diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 81befac015e1..69af490cce44 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -270,7 +270,7 @@ static void br_multicast_del_pg(struct net_bridge *br, del_timer(&p->timer); call_rcu_bh(&p->rcu, br_multicast_free_pg); - if (!mp->ports && !mp->mglist && + if (!mp->ports && !mp->mglist && mp->timer_armed && netif_running(br->dev)) mod_timer(&mp->timer, jiffies); -- cgit v1.2.3 From 1faabf2aab1fdaa1ace4e8c829d1b9cf7bfec2f1 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Fri, 19 Jul 2013 20:07:16 -0700 Subject: bridge: do not call setup_timer() multiple times commit 9f00b2e7cf24 ("bridge: only expire the mdb entry when query is received") added a nasty bug as an active timer can be reinitialized. setup_timer() must be done once, no matter how many time mod_timer() is called. br_multicast_new_group() is the right place to do this. Reported-by: Srivatsa S. Bhat Diagnosed-by: Thomas Gleixner Signed-off-by: Eric Dumazet Tested-by: Srivatsa S. Bhat Cc: Cong Wang Signed-off-by: David S. Miller --- net/bridge/br_multicast.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'net/bridge/br_multicast.c') diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 69af490cce44..4b99c9a27044 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -619,6 +619,9 @@ rehash: mp->br = br; mp->addr = *group; + setup_timer(&mp->timer, br_multicast_group_expired, + (unsigned long)mp); + hlist_add_head_rcu(&mp->hlist[mdb->ver], &mdb->mhash[hash]); mdb->size++; @@ -1126,7 +1129,6 @@ static int br_ip4_multicast_query(struct net_bridge *br, if (!mp) goto out; - setup_timer(&mp->timer, br_multicast_group_expired, (unsigned long)mp); mod_timer(&mp->timer, now + br->multicast_membership_interval); mp->timer_armed = true; @@ -1204,7 +1206,6 @@ static int br_ip6_multicast_query(struct net_bridge *br, if (!mp) goto out; - setup_timer(&mp->timer, br_multicast_group_expired, (unsigned long)mp); mod_timer(&mp->timer, now + br->multicast_membership_interval); mp->timer_armed = true; -- cgit v1.2.3 From b00589af3b04736376f24625ab0b394642e89e29 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Linus=20L=C3=BCssing?= Date: Thu, 1 Aug 2013 01:06:20 +0200 Subject: bridge: disable snooping if there is no querier MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If there is no querier on a link then we won't get periodic reports and therefore won't be able to learn about multicast listeners behind ports, potentially leading to lost multicast packets, especially for multicast listeners that joined before the creation of the bridge. These lost multicast packets can appear since c5c23260594 ("bridge: Add multicast_querier toggle and disable queries by default") in particular. With this patch we are flooding multicast packets if our querier is disabled and if we didn't detect any other querier. A grace period of the Maximum Response Delay of the querier is added to give multicast responses enough time to arrive and to be learned from before disabling the flooding behaviour again. Signed-off-by: Linus Lüssing Signed-off-by: David S. Miller --- net/bridge/br_multicast.c | 39 ++++++++++++++++++++++++++++++--------- 1 file changed, 30 insertions(+), 9 deletions(-) (limited to 'net/bridge/br_multicast.c') diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 4b99c9a27044..61c5e819380e 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -1014,6 +1014,16 @@ static int br_ip6_multicast_mld2_report(struct net_bridge *br, } #endif +static void br_multicast_update_querier_timer(struct net_bridge *br, + unsigned long max_delay) +{ + if (!timer_pending(&br->multicast_querier_timer)) + br->multicast_querier_delay_time = jiffies + max_delay; + + mod_timer(&br->multicast_querier_timer, + jiffies + br->multicast_querier_interval); +} + /* * Add port to router_list * list is maintained ordered by pointer value @@ -1064,11 +1074,11 @@ timer: static void br_multicast_query_received(struct net_bridge *br, struct net_bridge_port *port, - int saddr) + int saddr, + unsigned long max_delay) { if (saddr) - mod_timer(&br->multicast_querier_timer, - jiffies + br->multicast_querier_interval); + br_multicast_update_querier_timer(br, max_delay); else if (timer_pending(&br->multicast_querier_timer)) return; @@ -1096,8 +1106,6 @@ static int br_ip4_multicast_query(struct net_bridge *br, (port && port->state == BR_STATE_DISABLED)) goto out; - br_multicast_query_received(br, port, !!iph->saddr); - group = ih->group; if (skb->len == sizeof(*ih)) { @@ -1121,6 +1129,8 @@ static int br_ip4_multicast_query(struct net_bridge *br, IGMPV3_MRC(ih3->code) * (HZ / IGMP_TIMER_SCALE) : 1; } + br_multicast_query_received(br, port, !!iph->saddr, max_delay); + if (!group) goto out; @@ -1176,8 +1186,6 @@ static int br_ip6_multicast_query(struct net_bridge *br, (port && port->state == BR_STATE_DISABLED)) goto out; - br_multicast_query_received(br, port, !ipv6_addr_any(&ip6h->saddr)); - if (skb->len == sizeof(*mld)) { if (!pskb_may_pull(skb, sizeof(*mld))) { err = -EINVAL; @@ -1198,6 +1206,9 @@ static int br_ip6_multicast_query(struct net_bridge *br, max_delay = mld2q->mld2q_mrc ? MLDV2_MRC(ntohs(mld2q->mld2q_mrc)) : 1; } + br_multicast_query_received(br, port, !ipv6_addr_any(&ip6h->saddr), + max_delay); + if (!group) goto out; @@ -1643,6 +1654,8 @@ void br_multicast_init(struct net_bridge *br) br->multicast_querier_interval = 255 * HZ; br->multicast_membership_interval = 260 * HZ; + br->multicast_querier_delay_time = 0; + spin_lock_init(&br->multicast_lock); setup_timer(&br->multicast_router_timer, br_multicast_local_router_expired, 0); @@ -1831,6 +1844,8 @@ unlock: int br_multicast_set_querier(struct net_bridge *br, unsigned long val) { + unsigned long max_delay; + val = !!val; spin_lock_bh(&br->multicast_lock); @@ -1838,8 +1853,14 @@ int br_multicast_set_querier(struct net_bridge *br, unsigned long val) goto unlock; br->multicast_querier = val; - if (val) - br_multicast_start_querier(br); + if (!val) + goto unlock; + + max_delay = br->multicast_query_response_interval; + if (!timer_pending(&br->multicast_querier_timer)) + br->multicast_querier_delay_time = jiffies + max_delay; + + br_multicast_start_querier(br); unlock: spin_unlock_bh(&br->multicast_lock); -- cgit v1.2.3