From: David Ahern dsahern@kernel.org
commit 7a6b1ab7475fd6478eeaf5c9d1163e7a18125c8f upstream.
IFF_POINTOPOINT interfaces use NUD_NOARP entries for IPv6. It's possible to fill up the neighbour table with enough entries that it will overflow for valid connections after that.
This behaviour is more prevalent after commit 58956317c8de ("neighbor: Improve garbage collection") is applied, as it prevents removal from entries that are not NUD_FAILED, unless they are more than 5s old.
Fixes: 58956317c8de (neighbor: Improve garbage collection) Reported-by: Kasper Dupont kasperd@gjkwv.06.feb.2021.kasperd.net Signed-off-by: Thadeu Lima de Souza Cascardo cascardo@canonical.com Signed-off-by: David Ahern dsahern@kernel.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/core/neighbour.c | 1 + 1 file changed, 1 insertion(+)
--- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -238,6 +238,7 @@ static int neigh_forced_gc(struct neigh_
write_lock(&n->lock); if ((n->nud_state == NUD_FAILED) || + (n->nud_state == NUD_NOARP) || (tbl->is_multicast && tbl->is_multicast(n->primary_key)) || time_after(tref, n->updated))