diff options
| author | Ido Schimmel <idosch@nvidia.com> | 2023-03-15 16:11:48 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2023-03-17 11:05:49 +0300 |
| commit | da654c80a0ebba2e2a0614e017c9bbe57f643fe2 (patch) | |
| tree | b01f6fee03e7c4cb828016a7f8115cb2244836e1 /net/core | |
| parent | cc7f5022f810cf7bf4f1826dd620656c35942a13 (diff) | |
| download | linux-da654c80a0ebba2e2a0614e017c9bbe57f643fe2.tar.xz | |
rtnetlink: bridge: mcast: Relax group address validation in common code
In the upcoming VXLAN MDB implementation, the 0.0.0.0 and :: MDB entries
will act as catchall entries for unregistered IP multicast traffic in a
similar fashion to the 00:00:00:00:00:00 VXLAN FDB entry that is used to
transmit BUM traffic.
In deployments where inter-subnet multicast forwarding is used, not all
the VTEPs in a tenant domain are members in all the broadcast domains.
It is therefore advantageous to transmit BULL (broadcast, unknown
unicast and link-local multicast) and unregistered IP multicast traffic
on different tunnels. If the same tunnel was used, a VTEP only
interested in IP multicast traffic would also pull all the BULL traffic
and drop it as it is not a member in the originating broadcast domain
[1].
Prepare for this change by allowing the 0.0.0.0 group address in the
common rtnetlink MDB code and forbid it in the bridge driver. A similar
change is not needed for IPv6 because the common code only validates
that the group address is not the all-nodes address.
[1] https://datatracker.ietf.org/doc/html/draft-ietf-bess-evpn-irb-mcast#section-2.6
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/rtnetlink.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index f347d9fa78c7..b7b1661d0d56 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -6152,8 +6152,9 @@ static int rtnl_validate_mdb_entry(const struct nlattr *attr, } if (entry->addr.proto == htons(ETH_P_IP)) { - if (!ipv4_is_multicast(entry->addr.u.ip4)) { - NL_SET_ERR_MSG(extack, "IPv4 entry group address is not multicast"); + if (!ipv4_is_multicast(entry->addr.u.ip4) && + !ipv4_is_zeronet(entry->addr.u.ip4)) { + NL_SET_ERR_MSG(extack, "IPv4 entry group address is not multicast or 0.0.0.0"); return -EINVAL; } if (ipv4_is_local_multicast(entry->addr.u.ip4)) { |