diff options
| author |   daniel <daniel@dd-wrt.com> | 2016-06-24 12:35:18 +0200 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2016-06-28 08:03:04 -0400 |
| commit | 0888d5f3c0f183ea6177355752ada433d370ac89 (patch) | |
| tree | f1f08f5ef45de5caa8c8b7448ccec071540db60e /net/bridge/br_multicast.c | |
| parent | net/mlx5: use mlx5_buf_alloc_node instead of mlx5_buf_alloc in mlx5_wq_ll_create (diff) | |
| download | linux-dev-0888d5f3c0f183ea6177355752ada433d370ac89.tar.xz linux-dev-0888d5f3c0f183ea6177355752ada433d370ac89.zip | |
Bridge: Fix ipv6 mc snooping if bridge has no ipv6 address
The bridge is falsly dropping ipv6 mulitcast packets if there is:
1. No ipv6 address assigned on the brigde.
2. No external mld querier present.
3. The internal querier enabled.
When the bridge fails to build mld queries, because it has no
ipv6 address, it slilently returns, but keeps the local querier enabled.
This specific case causes confusing packet loss.
Ipv6 multicast snooping can only work if:
a) An external querier is present
OR
b) The bridge has an ipv6 address an is capable of sending own queries
Otherwise it has to forward/flood the ipv6 multicast traffic,
because snooping cannot work.
This patch fixes the issue by adding a flag to the bridge struct that
indicates that there is currently no ipv6 address assinged to the bridge
and returns a false state for the local querier in
__br_multicast_querier_exists().
Special thanks to Linus Lüssing.
Fixes: d1d81d4c3dd8 ("bridge: check return value of ipv6_dev_get_saddr()")
Signed-off-by: Daniel Danzberger <daniel@dd-wrt.com>
Acked-by: Linus Lüssing <linus.luessing@c0d3.blue>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/bridge/br_multicast.c')
| -rw-r--r-- | net/bridge/br_multicast.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c index 6852f3c7009c..43844144c9c4 100644 --- a/net/bridge/br_multicast.c +++ b/net/bridge/br_multicast.c @@ -464,8 +464,11 @@ static struct sk_buff *br_ip6_multicast_alloc_query(struct net_bridge *br, if (ipv6_dev_get_saddr(dev_net(br->dev), br->dev, &ip6h->daddr, 0, &ip6h->saddr)) { kfree_skb(skb); + br->has_ipv6_addr = 0; return NULL; } + + br->has_ipv6_addr = 1; ipv6_eth_mc_map(&ip6h->daddr, eth->h_dest); hopopt = (u8 *)(ip6h + 1); @@ -1745,6 +1748,7 @@ void br_multicast_init(struct net_bridge *br) br->ip6_other_query.delay_time = 0; br->ip6_querier.port = NULL; #endif + br->has_ipv6_addr = 1; spin_lock_init(&br->multicast_lock); setup_timer(&br->multicast_router_timer, |