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') 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: Linus Lüssing 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_device.c | 3 ++- net/bridge/br_input.c | 3 ++- net/bridge/br_multicast.c | 39 ++++++++++++++++++++++++++++++--------- net/bridge/br_private.h | 12 ++++++++++++ 4 files changed, 46 insertions(+), 11 deletions(-) (limited to 'net/bridge') diff --git a/net/bridge/br_device.c b/net/bridge/br_device.c index 2ef66781fedb..69363bd37f64 100644 --- a/net/bridge/br_device.c +++ b/net/bridge/br_device.c @@ -70,7 +70,8 @@ netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev) } mdst = br_mdb_get(br, skb, vid); - if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) + if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) && + br_multicast_querier_exists(br)) br_multicast_deliver(mdst, skb); else br_flood_deliver(br, skb, false); diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c index 1b8b8b824cd7..8c561c0aa636 100644 --- a/net/bridge/br_input.c +++ b/net/bridge/br_input.c @@ -101,7 +101,8 @@ int br_handle_frame_finish(struct sk_buff *skb) unicast = false; } else if (is_multicast_ether_addr(dest)) { mdst = br_mdb_get(br, skb, vid); - if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) { + if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) && + br_multicast_querier_exists(br)) { if ((mdst && mdst->mglist) || br_multicast_is_router(br)) skb2 = skb; 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); diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 3be89b3ce17b..2f7da41851bf 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -267,6 +267,7 @@ struct net_bridge unsigned long multicast_query_interval; unsigned long multicast_query_response_interval; unsigned long multicast_startup_query_interval; + unsigned long multicast_querier_delay_time; spinlock_t multicast_lock; struct net_bridge_mdb_htable __rcu *mdb; @@ -501,6 +502,13 @@ static inline bool br_multicast_is_router(struct net_bridge *br) (br->multicast_router == 1 && timer_pending(&br->multicast_router_timer)); } + +static inline bool br_multicast_querier_exists(struct net_bridge *br) +{ + return time_is_before_jiffies(br->multicast_querier_delay_time) && + (br->multicast_querier || + timer_pending(&br->multicast_querier_timer)); +} #else static inline int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port, @@ -557,6 +565,10 @@ static inline bool br_multicast_is_router(struct net_bridge *br) { return 0; } +static inline bool br_multicast_querier_exists(struct net_bridge *br) +{ + return false; +} static inline void br_mdb_init(void) { } -- cgit v1.2.3 From 248ba8ec05a2c3b118c2224e57eb10c128176ab1 Mon Sep 17 00:00:00 2001 From: Linus Lüssing Date: Tue, 6 Aug 2013 00:32:05 +0200 Subject: bridge: don't try to update timers in case of broken MLD queries MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Currently we are reading an uninitialized value for the max_delay variable when snooping an MLD query message of invalid length and would update our timers with that. Fixing this by simply ignoring such broken MLD queries (just like we do for IGMP already). This is a regression introduced by: "bridge: disable snooping if there is no querier" (b00589af3b04) Reported-by: Paul Bolle Signed-off-by: Linus Lüssing Signed-off-by: David S. Miller --- net/bridge/br_multicast.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/bridge') diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 61c5e819380e..08e576ada0b2 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -1195,7 +1195,7 @@ static int br_ip6_multicast_query(struct net_bridge *br, max_delay = msecs_to_jiffies(ntohs(mld->mld_maxdelay)); if (max_delay) group = &mld->mld_mca; - } else if (skb->len >= sizeof(*mld2q)) { + } else { if (!pskb_may_pull(skb, sizeof(*mld2q))) { err = -EINVAL; goto out; -- cgit v1.2.3 From 15401946f9b720efdd20bda3ae79725e9c586897 Mon Sep 17 00:00:00 2001 From: Wang Sheng-Hui Date: Tue, 6 Aug 2013 08:44:46 +0800 Subject: bridge: correct the comment for file br_sysfs_br.c br_sysfs_if.c is for sysfs attributes of bridge ports, while br_sysfs_br.c is for sysfs attributes of bridge itself. Correct the comment here. Signed-off-by: Wang Sheng-Hui Signed-off-by: David S. Miller --- net/bridge/br_sysfs_br.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'net/bridge') diff --git a/net/bridge/br_sysfs_br.c b/net/bridge/br_sysfs_br.c index 394bb96b6087..3b9637fb7939 100644 --- a/net/bridge/br_sysfs_br.c +++ b/net/bridge/br_sysfs_br.c @@ -1,5 +1,5 @@ /* - * Sysfs attributes of bridge ports + * Sysfs attributes of bridge * Linux ethernet bridge * * Authors: -- cgit v1.2.3