From 7f92083eb58f85ea114d97f65fcbe22be5b0468d Mon Sep 17 00:00:00 2001 From: Nicolas Dichtel Date: Fri, 30 Sep 2016 11:11:07 +0200 Subject: vti6: flush x-netns xfrm cache when vti interface is removed This is the same fix than commit a5d0dc810abf ("vti: flush x-netns xfrm cache when vti interface is removed") This patch fixes a refcnt problem when a x-netns vti6 interface is removed: unregister_netdevice: waiting for vti6_test to become free. Usage count = 1 Here is a script to reproduce the problem: ip link set dev ntfp2 up ip addr add dev ntfp2 2001::1/64 ip link add vti6_test type vti6 local 2001::1 remote 2001::2 key 1 ip netns add secure ip link set vti6_test netns secure ip netns exec secure ip link set vti6_test up ip netns exec secure ip link s lo up ip netns exec secure ip addr add dev vti6_test 2003::1/64 ip -6 xfrm policy add dir out tmpl src 2001::1 dst 2001::2 proto esp \ mode tunnel mark 1 ip -6 xfrm policy add dir in tmpl src 2001::2 dst 2001::1 proto esp \ mode tunnel mark 1 ip xfrm state add src 2001::1 dst 2001::2 proto esp spi 1 mode tunnel \ enc des3_ede 0x112233445566778811223344556677881122334455667788 mark 1 ip xfrm state add src 2001::2 dst 2001::1 proto esp spi 1 mode tunnel \ enc des3_ede 0x112233445566778811223344556677881122334455667788 mark 1 ip netns exec secure ping6 -c 4 2003::2 ip netns del secure CC: Lance Richardson Signed-off-by: Nicolas Dichtel Acked-by: Lance Richardson Signed-off-by: Steffen Klassert --- net/ipv6/ip6_vti.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/net/ipv6/ip6_vti.c b/net/ipv6/ip6_vti.c index 8a02ca8a11af..c299c1e2bbf0 100644 --- a/net/ipv6/ip6_vti.c +++ b/net/ipv6/ip6_vti.c @@ -1138,6 +1138,33 @@ static struct xfrm6_protocol vti_ipcomp6_protocol __read_mostly = { .priority = 100, }; +static bool is_vti6_tunnel(const struct net_device *dev) +{ + return dev->netdev_ops == &vti6_netdev_ops; +} + +static int vti6_device_event(struct notifier_block *unused, + unsigned long event, void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + struct ip6_tnl *t = netdev_priv(dev); + + if (!is_vti6_tunnel(dev)) + return NOTIFY_DONE; + + switch (event) { + case NETDEV_DOWN: + if (!net_eq(t->net, dev_net(dev))) + xfrm_garbage_collect(t->net); + break; + } + return NOTIFY_DONE; +} + +static struct notifier_block vti6_notifier_block __read_mostly = { + .notifier_call = vti6_device_event, +}; + /** * vti6_tunnel_init - register protocol and reserve needed resources * @@ -1148,6 +1175,8 @@ static int __init vti6_tunnel_init(void) const char *msg; int err; + register_netdevice_notifier(&vti6_notifier_block); + msg = "tunnel device"; err = register_pernet_device(&vti6_net_ops); if (err < 0) @@ -1180,6 +1209,7 @@ xfrm_proto_ah_failed: xfrm_proto_esp_failed: unregister_pernet_device(&vti6_net_ops); pernet_dev_failed: + unregister_netdevice_notifier(&vti6_notifier_block); pr_err("vti6 init: failed to register %s\n", msg); return err; } @@ -1194,6 +1224,7 @@ static void __exit vti6_tunnel_cleanup(void) xfrm6_protocol_deregister(&vti_ah6_protocol, IPPROTO_AH); xfrm6_protocol_deregister(&vti_esp6_protocol, IPPROTO_ESP); unregister_pernet_device(&vti6_net_ops); + unregister_netdevice_notifier(&vti6_notifier_block); } module_init(vti6_tunnel_init); -- cgit v1.2.3 From 330e832abda923df06a4ca6d3faac6e9c1b42548 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Thu, 17 Nov 2016 13:21:46 +0100 Subject: xfrm: unbreak xfrm_sk_policy_lookup if we succeed grabbing the refcount, then if (err && !xfrm_pol_hold_rcu) will evaluate to false so this hits last else branch which then sets policy to ERR_PTR(0). Fixes: ae33786f73a7ce ("xfrm: policy: only use rcu in xfrm_sk_policy_lookup") Reported-by: Nicolas Dichtel Tested-by: Nicolas Dichtel Signed-off-by: Florian Westphal Signed-off-by: Steffen Klassert --- net/xfrm/xfrm_policy.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/net/xfrm/xfrm_policy.c b/net/xfrm/xfrm_policy.c index fd6986634e6f..5bf7e1bfeac7 100644 --- a/net/xfrm/xfrm_policy.c +++ b/net/xfrm/xfrm_policy.c @@ -1268,12 +1268,14 @@ static struct xfrm_policy *xfrm_sk_policy_lookup(const struct sock *sk, int dir, err = security_xfrm_policy_lookup(pol->security, fl->flowi_secid, policy_to_flow_dir(dir)); - if (!err && !xfrm_pol_hold_rcu(pol)) - goto again; - else if (err == -ESRCH) + if (!err) { + if (!xfrm_pol_hold_rcu(pol)) + goto again; + } else if (err == -ESRCH) { pol = NULL; - else + } else { pol = ERR_PTR(err); + } } else pol = NULL; } -- cgit v1.2.3 From 6b226487815574193c1da864f2eac274781a2b0c Mon Sep 17 00:00:00 2001 From: Miroslav Urbanek Date: Mon, 21 Nov 2016 15:48:21 +0100 Subject: flowcache: Increase threshold for refusing new allocations MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The threshold for OOM protection is too small for systems with large number of CPUs. Applications report ENOBUFs on connect() every 10 minutes. The problem is that the variable net->xfrm.flow_cache_gc_count is a global counter while the variable fc->high_watermark is a per-CPU constant. Take the number of CPUs into account as well. Fixes: 6ad3122a08e3 ("flowcache: Avoid OOM condition under preasure") Reported-by: Lukáš Koldrt Tested-by: Jan Hejl Signed-off-by: Miroslav Urbanek Signed-off-by: Steffen Klassert --- net/core/flow.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/net/core/flow.c b/net/core/flow.c index 3937b1b68d5b..18e8893d4be5 100644 --- a/net/core/flow.c +++ b/net/core/flow.c @@ -95,7 +95,6 @@ static void flow_cache_gc_task(struct work_struct *work) list_for_each_entry_safe(fce, n, &gc_list, u.gc_list) { flow_entry_kill(fce, xfrm); atomic_dec(&xfrm->flow_cache_gc_count); - WARN_ON(atomic_read(&xfrm->flow_cache_gc_count) < 0); } } @@ -236,9 +235,8 @@ flow_cache_lookup(struct net *net, const struct flowi *key, u16 family, u8 dir, if (fcp->hash_count > fc->high_watermark) flow_cache_shrink(fc, fcp); - if (fcp->hash_count > 2 * fc->high_watermark || - atomic_read(&net->xfrm.flow_cache_gc_count) > fc->high_watermark) { - atomic_inc(&net->xfrm.flow_cache_genid); + if (atomic_read(&net->xfrm.flow_cache_gc_count) > + 2 * num_online_cpus() * fc->high_watermark) { flo = ERR_PTR(-ENOBUFS); goto ret_object; } -- cgit v1.2.3