ipv4: Don't do expensive useless work during inetdev destroy.
When an inetdev is destroyed, every address assigned to the interface
is removed. And in this scenerio we do two pointless things which can
be very expensive if the number of assigned interfaces is large:
1) Address promotion. We are deleting all addresses, so there is no
point in doing this.
2) A full nf conntrack table purge for every address. We only need to
do this once, as is already caught by the existing
masq_dev_notifier so masq_inet_event() can skip this.
Reported-by: Solar Designer <solar@openwall.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Cyrill Gorcunov <gorcunov@openvz.org>
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
index 4734475..21add55 100644
--- a/net/ipv4/fib_frontend.c
+++ b/net/ipv4/fib_frontend.c
@@ -922,6 +922,9 @@
subnet = 1;
}
+ if (in_dev->dead)
+ goto no_promotions;
+
/* Deletion is more complicated than add.
* We should take care of not to delete too much :-)
*
@@ -997,6 +1000,7 @@
}
}
+no_promotions:
if (!(ok & BRD_OK))
fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim);
if (subnet && ifa->ifa_prefixlen < 31) {