From: Nikolay Aleksandrov nikolay@nvidia.com
commit f2f3729fb65c5c2e6db234e6316b71a7bdc4b30b upstream.
When a user-space software manages fdb entries externally it should set the ext_learn flag which marks the fdb entry as externally managed and avoids expiring it (they're treated as static fdbs). Unfortunately on events where fdb entries are flushed (STP down, netlink fdb flush etc) these fdbs are also deleted automatically by the bridge. That in turn causes trouble for the managing user-space software (e.g. in MLAG setups we lose remote fdb entries on port flaps). These entries are completely externally managed so we should avoid automatically deleting them, the only exception are offloaded entries (i.e. BR_FDB_ADDED_BY_EXT_LEARN + BR_FDB_OFFLOADED). They are flushed as before.
Fixes: eb100e0e24a2 ("net: bridge: allow to add externally learned entries from user-space") Signed-off-by: Nikolay Aleksandrov nikolay@nvidia.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- net/bridge/br_fdb.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/net/bridge/br_fdb.c +++ b/net/bridge/br_fdb.c @@ -404,6 +404,8 @@ void br_fdb_delete_by_port(struct net_br
if (!do_all) if (test_bit(BR_FDB_STATIC, &f->flags) || + (test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags) && + !test_bit(BR_FDB_OFFLOADED, &f->flags)) || (vid && f->key.vlan_id != vid)) continue;