diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 853b947edf87..701cf46b89de 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -1659,11 +1659,38 @@ again_under_lmqt: } } +static void br_multicast_read_querier(const struct bridge_mcast_querier *querier, + struct bridge_mcast_querier *dest) +{ + unsigned int seq; + + memset(dest, 0, sizeof(*dest)); + do { + seq = read_seqcount_begin(&querier->seq); + dest->port_ifidx = querier->port_ifidx; + memcpy(&dest->addr, &querier->addr, sizeof(struct br_ip)); + } while (read_seqcount_retry(&querier->seq, seq)); +} + +static void br_multicast_update_querier(struct net_bridge_mcast *brmctx, + struct bridge_mcast_querier *querier, + int ifindex, + struct br_ip *saddr) +{ + lockdep_assert_held_once(&brmctx->br->multicast_lock); + + write_seqcount_begin(&querier->seq); + querier->port_ifidx = ifindex; + memcpy(&querier->addr, saddr, sizeof(*saddr)); + write_seqcount_end(&querier->seq); +} + static void br_multicast_send_query(struct net_bridge_mcast *brmctx, struct net_bridge_mcast_port *pmctx, struct bridge_mcast_own_query *own_query) { struct bridge_mcast_other_query *other_query = NULL; + struct bridge_mcast_querier *querier; struct br_ip br_group; unsigned long time; @@ -1676,10 +1703,12 @@ static void br_multicast_send_query(struct net_bridge_mcast *brmctx, if (pmctx ? (own_query == &pmctx->ip4_own_query) : (own_query == &brmctx->ip4_own_query)) { + querier = &brmctx->ip4_querier; other_query = &brmctx->ip4_other_query; br_group.proto = htons(ETH_P_IP); #if IS_ENABLED(CONFIG_IPV6) } else { + querier = &brmctx->ip6_querier; other_query = &brmctx->ip6_other_query; br_group.proto = htons(ETH_P_IPV6); #endif @@ -1688,6 +1717,13 @@ static void br_multicast_send_query(struct net_bridge_mcast *brmctx, if (!other_query || timer_pending(&other_query->timer)) return; + /* we're about to select ourselves as querier */ + if (!pmctx && querier->port_ifidx) { + struct br_ip zeroip = {}; + + br_multicast_update_querier(brmctx, querier, 0, &zeroip); + } + __br_multicast_send_query(brmctx, pmctx, NULL, NULL, &br_group, false, 0, NULL); @@ -2830,9 +2866,9 @@ unlock_continue: static bool br_ip4_multicast_select_querier(struct net_bridge_mcast *brmctx, struct net_bridge_mcast_port *pmctx, - __be32 saddr) + struct br_ip *saddr) { - struct net_bridge_port *port = pmctx ? pmctx->port : NULL; + int port_ifidx = pmctx ? pmctx->port->dev->ifindex : 0; if (!timer_pending(&brmctx->ip4_own_query.timer) && !timer_pending(&brmctx->ip4_other_query.timer)) @@ -2841,17 +2877,14 @@ static bool br_ip4_multicast_select_querier(struct net_bridge_mcast *brmctx, if (!brmctx->ip4_querier.addr.src.ip4) goto update; - if (ntohl(saddr) <= ntohl(brmctx->ip4_querier.addr.src.ip4)) + if (ntohl(saddr->src.ip4) <= ntohl(brmctx->ip4_querier.addr.src.ip4)) goto update; return false; update: - brmctx->ip4_querier.addr.src.ip4 = saddr; - - /* update protected by general multicast_lock by caller */ - if (port) - brmctx->ip4_querier.port_ifidx = port->dev->ifindex; + br_multicast_update_querier(brmctx, &brmctx->ip4_querier, port_ifidx, + saddr); return true; } @@ -2859,25 +2892,23 @@ update: #if IS_ENABLED(CONFIG_IPV6) static bool br_ip6_multicast_select_querier(struct net_bridge_mcast *brmctx, struct net_bridge_mcast_port *pmctx, - struct in6_addr *saddr) + struct br_ip *saddr) { - struct net_bridge_port *port = pmctx ? pmctx->port : NULL; + int port_ifidx = pmctx ? pmctx->port->dev->ifindex : 0; if (!timer_pending(&brmctx->ip6_own_query.timer) && !timer_pending(&brmctx->ip6_other_query.timer)) goto update; - if (ipv6_addr_cmp(saddr, &brmctx->ip6_querier.addr.src.ip6) <= 0) + if (ipv6_addr_cmp(&saddr->src.ip6, + &brmctx->ip6_querier.addr.src.ip6) <= 0) goto update; return false; update: - brmctx->ip6_querier.addr.src.ip6 = *saddr; - - /* update protected by general multicast_lock by caller */ - if (port) - brmctx->ip6_querier.port_ifidx = port->dev->ifindex; + br_multicast_update_querier(brmctx, &brmctx->ip6_querier, port_ifidx, + saddr); return true; } @@ -3084,7 +3115,7 @@ br_ip4_multicast_query_received(struct net_bridge_mcast *brmctx, struct br_ip *saddr, unsigned long max_delay) { - if (!br_ip4_multicast_select_querier(brmctx, pmctx, saddr->src.ip4)) + if (!br_ip4_multicast_select_querier(brmctx, pmctx, saddr)) return; br_multicast_update_query_timer(brmctx, query, max_delay); @@ -3099,7 +3130,7 @@ br_ip6_multicast_query_received(struct net_bridge_mcast *brmctx, struct br_ip *saddr, unsigned long max_delay) { - if (!br_ip6_multicast_select_querier(brmctx, pmctx, &saddr->src.ip6)) + if (!br_ip6_multicast_select_querier(brmctx, pmctx, saddr)) return; br_multicast_update_query_timer(brmctx, query, max_delay); @@ -3119,7 +3150,7 @@ static void br_ip4_multicast_query(struct net_bridge_mcast *brmctx, struct igmpv3_query *ih3; struct net_bridge_port_group *p; struct net_bridge_port_group __rcu **pp; - struct br_ip saddr; + struct br_ip saddr = {}; unsigned long max_delay; unsigned long now = jiffies; __be32 group; @@ -3199,7 +3230,7 @@ static int br_ip6_multicast_query(struct net_bridge_mcast *brmctx, struct mld2_query *mld2q; struct net_bridge_port_group *p; struct net_bridge_port_group __rcu **pp; - struct br_ip saddr; + struct br_ip saddr = {}; unsigned long max_delay; unsigned long now = jiffies; unsigned int offset = skb_transport_offset(skb); @@ -3677,7 +3708,6 @@ static void br_multicast_query_expired(struct net_bridge_mcast *brmctx, if (query->startup_sent < brmctx->multicast_startup_query_count) query->startup_sent++; - querier->port_ifidx = 0; br_multicast_send_query(brmctx, NULL, query); out: spin_unlock(&brmctx->br->multicast_lock); @@ -3735,11 +3765,13 @@ void br_multicast_ctx_init(struct net_bridge *br, brmctx->ip4_other_query.delay_time = 0; brmctx->ip4_querier.port_ifidx = 0; + seqcount_init(&brmctx->ip4_querier.seq); brmctx->multicast_igmp_version = 2; #if IS_ENABLED(CONFIG_IPV6) brmctx->multicast_mld_version = 1; brmctx->ip6_other_query.delay_time = 0; brmctx->ip6_querier.port_ifidx = 0; + seqcount_init(&brmctx->ip6_querier.seq); #endif timer_setup(&brmctx->ip4_mc_router_timer, diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 30ca978676f3..70e2d9a7f105 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -82,6 +82,7 @@ struct bridge_mcast_other_query { struct bridge_mcast_querier { struct br_ip addr; int port_ifidx; + seqcount_t seq; }; /* IGMP/MLD statistics */