bridge: Always flood broadcast packets (44661462) · Commits · 戴 / test

As is_multicast_ether_addr returns true on broadcast packets as well, we need to explicitly exclude broadcast packets so that they're always flooded. This wasn't an issue before as broadcast packets were considered to be an unregistered multicast group, which were always flooded. However, as we now only flood such packets to router ports, this is no longer acceptable. Reported-by:

Michael Guntsche <mike@it-loops.com> Signed-off-by:

Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by:

David S. Miller <davem@davemloft.net>

net/bridge/br_device.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -49,7 +49,9 @@ netdev_tx_t br_dev_xmit(struct sk_buff skb, struct net_device dev)
		skb_pull(skb, ETH_HLEN);

		rcu_read_lock();
		if (is_multicast_ether_addr(dest)) {
		if (is_broadcast_ether_addr(dest))
		br_flood_deliver(br, skb);
		else if (is_multicast_ether_addr(dest)) {
		if (unlikely(netpoll_tx_running(dev))) {
		br_flood_deliver(br, skb);
		goto out;

net/bridge/br_input.c

+4 −2

Original line number	Diff line number	Diff line
		@@ -60,7 +60,7 @@ int br_handle_frame_finish(struct sk_buff *skb)
		br = p->br;
		br_fdb_update(br, p, eth_hdr(skb)->h_source);

		if (is_multicast_ether_addr(dest) &&
		if (!is_broadcast_ether_addr(dest) && is_multicast_ether_addr(dest) &&
		br_multicast_rcv(br, p, skb))
		goto drop;

		@@ -77,7 +77,9 @@ int br_handle_frame_finish(struct sk_buff *skb)

		dst = NULL;

		if (is_multicast_ether_addr(dest)) {
		if (is_broadcast_ether_addr(dest))
		skb2 = skb;
		else if (is_multicast_ether_addr(dest)) {
		mdst = br_mdb_get(br, skb);
		if (mdst \|\| BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) {
		if ((mdst && mdst->mglist) \|\|

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