diff options
| author | David S. Miller <davem@davemloft.net> | 2016-03-13 23:28:00 -0400 |
|---|---|---|
| committer | Moyster <oysterized@gmail.com> | 2016-11-17 12:11:46 +0100 |
| commit | f8838b48efe5a690b68eca4634b01f03e04560b4 (patch) | |
| tree | 17805874bfb646f783f6ee000b2342f9145dc1c3 /net/ipv4 | |
| parent | 8da08bf6c812ac3c0dad28baa43db60952ba1535 (diff) | |
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.
Change-Id: I4b2a3ed665543728451c21465fb90ec89f739135
Reported-by: Solar Designer <solar@openwall.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Cyrill Gorcunov <gorcunov@openvz.org>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/devinet.c | 4 | ||||
| -rw-r--r-- | net/ipv4/fib_frontend.c | 4 | ||||
| -rw-r--r-- | net/ipv4/netfilter/ipt_MASQUERADE.c | 12 |
3 files changed, 18 insertions, 2 deletions
diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index b151e0ac7..802cb6ffe 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -324,6 +324,9 @@ static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, ASSERT_RTNL(); + if (in_dev->dead) + goto no_promotions; + /* 1. Deleting primary ifaddr forces deletion all secondaries * unless alias promotion is set **/ @@ -370,6 +373,7 @@ static void __inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap, fib_del_ifaddr(ifa, ifa1); } +no_promotions: /* 2. Unlink it */ *ifap = ifa1->ifa_next; diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 4fc63bd9a..4f3295ad5 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -841,6 +841,9 @@ void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim) 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 :-) * @@ -916,6 +919,7 @@ void fib_del_ifaddr(struct in_ifaddr *ifa, struct in_ifaddr *iprim) } } +no_promotions: if (!(ok & BRD_OK)) fib_magic(RTM_DELROUTE, RTN_BROADCAST, ifa->ifa_broadcast, 32, prim); if (subnet && ifa->ifa_prefixlen < 31) { diff --git a/net/ipv4/netfilter/ipt_MASQUERADE.c b/net/ipv4/netfilter/ipt_MASQUERADE.c index 5d5d4d1be..c1e4ebdae 100644 --- a/net/ipv4/netfilter/ipt_MASQUERADE.c +++ b/net/ipv4/netfilter/ipt_MASQUERADE.c @@ -128,8 +128,16 @@ static int masq_inet_event(struct notifier_block *this, unsigned long event, void *ptr) { - struct net_device *dev = ((struct in_ifaddr *)ptr)->ifa_dev->dev; - return masq_device_event(this, event, dev); + struct in_device *idev = ((struct in_ifaddr *)ptr)->ifa_dev; + /* The masq_dev_notifier will catch the case of the device going + * down. So if the inetdev is dead and being destroyed we have + * no work to do. Otherwise this is an individual address removal + * and we have to perform the flush. + */ + if (idev->dead) + return NOTIFY_DONE; + + return masq_device_event(this, event, idev->dev); } static struct notifier_block masq_dev_notifier = { |