@@ -1249,6 +1249,12 @@ static int br_mdb_config_init(struct br_mdb_config *cfg, struct net_device *dev,
}
}
+ if (cfg->entry->addr.proto == htons(ETH_P_IP) &&
+ ipv4_is_zeronet(cfg->entry->addr.u.ip4)) {
+ NL_SET_ERR_MSG_MOD(extack, "IPv4 entry group address 0.0.0.0 is not allowed");
+ return -EINVAL;
+ }
+
if (tb[MDBA_SET_ENTRY_ATTRS])
return br_mdb_config_attrs_init(tb[MDBA_SET_ENTRY_ATTRS], cfg,
extack);
@@ -6149,8 +6149,9 @@ 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)) {
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> --- net/bridge/br_mdb.c | 6 ++++++ net/core/rtnetlink.c | 5 +++-- 2 files changed, 9 insertions(+), 2 deletions(-)