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Since the introduction of mcast_max_groups, a host behind a port that reached its maximum can use this to exhaust the MDB and disable multicast snooping. Patch #1 fixes the problem by deleting the entry upon failure. Patch #2 adds a selftest. Ido Schimmel (2): bridge: mcast: Delete empty MDB entry when port group creation fails selftests: forwarding: bridge_mdb_max: Add a test for rejected MDB entries net/bridge/br_mdb.c | 16 +- net/bridge/br_multicast.c | 9 ++ net/bridge/br_private.h | 1 + .../net/forwarding/bridge_mdb_max.sh | 138 ++++++++++++++++++ 4 files changed, 161 insertions(+), 3 deletions(-) -- 2.56.0