linux-toradex.git/net/bridge/br_multicast.c, branch v4.9.90

bridge: multicast: restore perm router ports on multicast enable

2016-10-18T17:52:13+00:00

Satish reported a problem with the perm multicast router ports not getting
reenabled after some series of events, in particular if it happens that the
multicast snooping has been disabled and the port goes to disabled state
then it will be deleted from the router port list, but if it moves into
non-disabled state it will not be re-added because the mcast snooping is
still disabled, and enabling snooping later does nothing.

Here are the steps to reproduce, setup br0 with snooping enabled and eth1
added as a perm router (multicast_router = 2):
1. $ echo 0 > /sys/class/net/br0/bridge/multicast_snooping
2. $ ip l set eth1 down
^ This step deletes the interface from the router list
3. $ ip l set eth1 up
^ This step does not add it again because mcast snooping is disabled
4. $ echo 1 > /sys/class/net/br0/bridge/multicast_snooping
5. $ bridge -d -s mdb show


At this point we have mcast enabled and eth1 as a perm router (value = 2)
but it is not in the router list which is incorrect.

After this change:
1. $ echo 0 > /sys/class/net/br0/bridge/multicast_snooping
2. $ ip l set eth1 down
^ This step deletes the interface from the router list
3. $ ip l set eth1 up
^ This step does not add it again because mcast snooping is disabled
4. $ echo 1 > /sys/class/net/br0/bridge/multicast_snooping
5. $ bridge -d -s mdb show
router ports on br0: eth1

Note: we can directly do br_multicast_enable_port for all because the
querier timer already has checks for the port state and will simply
expire if it's in blocking/disabled. See the comment added by
commit 9aa66382163e7 ("bridge: multicast: add a comment to
br_port_state_selection about blocking state")

Fixes: 561f1103a2b7 ("bridge: Add multicast_snooping sysfs toggle")
Reported-by: Satish Ashok 
Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

bridge: re-introduce 'fix parsing of MLDv2 reports'

2016-08-31T16:29:58+00:00

commit bc8c20acaea1 ("bridge: multicast: treat igmpv3 report with
INCLUDE and no sources as a leave") seems to have accidentally reverted
commit 47cc84ce0c2f ("bridge: fix parsing of MLDv2 reports"). This
commit brings back a change to br_ip6_multicast_mld2_report() where
parsing of MLDv2 reports stops when the first group is successfully
added to the MDB cache.

Fixes: bc8c20acaea1 ("bridge: multicast: treat igmpv3 report with INCLUDE and no sources as a leave")
Signed-off-by: Davide Caratti 
Acked-by: Nikolay Aleksandrov 
Acked-by: Thadeu Lima de Souza Cascardo 
Signed-off-by: David S. Miller

net: bridge: extend MLD/IGMP query stats

2016-07-09T21:40:09+00:00

As was suggested this patch adds support for the different versions of MLD
and IGMP query types. Since the user visible structure is still in net-next
we can augment it instead of adding netlink attributes.
The distinction between the different IGMP/MLD query types is done as
suggested in Section 7.1, RFC 3376 [1] and Section 8.1, RFC 3810 [2] based
on query payload size and code for IGMP. Since all IGMP packets go through
multicast_rcv() and it uses ip_mc_check_igmp/ipv6_mc_check_mld we can be
sure that at least the ip/ipv6 header can be directly used.

[1] https://tools.ietf.org/html/rfc3376#section-7
[2] https://tools.ietf.org/html/rfc3810#section-8.1

Suggested-by: Linus Lüssing 
Signed-off-by: Nikolay Aleksandrov 
Acked-by: Stephen Hemminger 
Signed-off-by: David S. Miller

net: bridge: add support for IGMP/MLD stats and export them via netlink

2016-06-30T10:18:24+00:00

This patch adds stats support for the currently used IGMP/MLD types by the
bridge. The stats are per-port (plus one stat per-bridge) and per-direction
(RX/TX). The stats are exported via netlink via the new linkxstats API
(RTM_GETSTATS). In order to minimize the performance impact, a new option
is used to enable/disable the stats - multicast_stats_enabled, similar to
the recent vlan stats. Also in order to avoid multiple IGMP/MLD type
lookups and checks, we make use of the current "igmp" member of the bridge
private skb->cb region to record the type on Rx (both host-generated and
external packets pass by multicast_rcv()). We can do that since the igmp
member was used as a boolean and all the valid IGMP/MLD types are positive
values. The normal bridge fast-path is not affected at all, the only
affected paths are the flooding ones and since we make use of the IGMP/MLD
type, we can quickly determine if the packet should be counted using
cache-hot data (cb's igmp member). We add counters for:
* IGMP Queries
* IGMP Leaves
* IGMP v1/v2/v3 reports

* MLD Queries
* MLD Leaves
* MLD v1/v2 reports

These are invaluable when monitoring or debugging complex multicast setups
with bridges.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

Bridge: Fix ipv6 mc snooping if bridge has no ipv6 address

2016-06-28T12:03:04+00:00

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 
Acked-by: Linus Lüssing 
Signed-off-by: David S. Miller

bridge: fix igmp / mld query parsing

2016-05-06T16:55:13+00:00

With the newly introduced helper functions the skb pulling is hidden
in the checksumming function - and undone before returning to the
caller.

The IGMP and MLD query parsing functions in the bridge still
assumed that the skb is pointing to the beginning of the IGMP/MLD
message while it is now kept at the beginning of the IPv4/6 header.

If there is a querier somewhere else, then this either causes
the multicast snooping to stay disabled even though it could be
enabled. Or, if we have the querier enabled too, then this can
create unnecessary IGMP / MLD query messages on the link.

Fixing this by taking the offset between IP and IGMP/MLD header into
account, too.

Fixes: 9afd85c9e455 ("net: Export IGMP/MLD message validation code")
Reported-by: Simon Wunderlich 
Signed-off-by: Linus Lüssing 
Signed-off-by: David S. Miller

bridge: mdb: Marking port-group as offloaded

2016-04-24T18:23:32+00:00

There is a race-condition when updating the mdb offload flag without using
the mulicast_lock. This reverts commit 9e8430f8d60d98 ("bridge: mdb:
Passing the port-group pointer to br_mdb module").

This patch marks offloaded MDB entry as "offload" by changing the port-
group flags and marks it as MDB_PG_FLAGS_OFFLOAD.

When switchdev PORT_MDB succeeded and adds a multicast group, a completion
callback is been invoked "br_mdb_complete". The completion function
locks the multicast_lock and finds the right net_bridge_port_group and
marks it as offloaded.

Fixes: 9e8430f8d60d98 ("bridge: mdb: Passing the port-group pointer to br_mdb module")
Reported-by: Nikolay Aleksandrov 
Signed-off-by: Elad Raz 
Signed-off-by: Jiri Pirko 
Reviewed-by: Ido Schimmel 
Acked-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

bridge: mcast: add support for temporary port router

2016-03-01T21:55:07+00:00

Add support for a temporary router port which doesn't depend only on the
incoming query. It can be refreshed if set to the same value, which is
a no-op for the rest.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

bridge: mcast: do nothing if port's multicast_router is set to the same val

2016-03-01T21:55:07+00:00

This is needed for the upcoming temporary port router. There's no point
to go through the logic if the value is the same.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller

bridge: mcast: use names for the different multicast_router types

2016-03-01T21:55:07+00:00

Using raw values makes it difficult to extend and also understand the
code, give them names and do explicit per-option manipulation in
br_multicast_set_port_router.

Signed-off-by: Nikolay Aleksandrov 
Signed-off-by: David S. Miller