We saw the following extra refcount release on veth device:
kernel: [7957821.463992] unregister_netdevice: waiting for mesos50284 to become free. Usage count = -1
Since we heavily use mirred action to redirect packets to veth, I think
this is caused by the following race condition:
CPU0:
tcf_mirred_release(): (in RCU callback)
struct net_device *dev = rcu_dereference_protected(m->tcfm_dev, 1);
CPU1:
mirred_device_event():
spin_lock_bh(&mirred_list_lock);
list_for_each_entry(m, &mirred_list, tcfm_list) {
if (rcu_access_pointer(m->tcfm_dev) == dev) {
dev_put(dev);
/* Note : no rcu grace period necessary, as
* net_device are already rcu protected.
*/
RCU_INIT_POINTER(m->tcfm_dev, NULL);
}
}
spin_unlock_bh(&mirred_list_lock);
CPU0:
tcf_mirred_release():
spin_lock_bh(&mirred_list_lock);
list_del(&m->tcfm_list);
spin_unlock_bh(&mirred_list_lock);
if (dev) // <======== Stil refers to the old m->tcfm_dev
dev_put(dev); // <======== dev_put() is called on it again
The action init code path is good because it is impossible to modify
an action that is being removed.
So, fix this by moving everything under the spinlock.
Fixes: 2ee22a90c7 ("net_sched: act_mirred: remove spinlock in fast path")
Fixes: 6bd00b8506 ("act_mirred: fix a race condition on mirred_list")
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The nf_conntrack_core.c fix in 'net' is not relevant in 'net-next'
because we no longer have a per-netns conntrack hash.
The ip_gre.c conflict as well as the iwlwifi ones were cases of
overlapping changes.
Conflicts:
drivers/net/wireless/intel/iwlwifi/mvm/tx.c
net/ipv4/ip_gre.c
net/netfilter/nf_conntrack_core.c
Signed-off-by: David S. Miller <davem@davemloft.net>
The process below was broken and is fixed with this patch.
//add an mirred action and give it an instance id of 1
sudo tc actions add action mirred egress mirror dev $MDEV index 1
//create a filter which binds to mirred action id 1
sudo tc filter add dev $DEV parent ffff: protocol ip prio 1 u32\
match ip dst 17.0.0.1/32 flowid 1:10 action mirred index 1
Message before bug fix was:
RTNETLINK answers: Invalid argument
We have an error talking to the kernel
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Reviewed-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently tc actions are stored in a per-module hashtable,
therefore are visible to all network namespaces. This is
probably the last part of the tc subsystem which is not
aware of netns now. This patch makes them per-netns,
several tc action API's need to be adjusted for this.
The tc action API code is ugly due to historical reasons,
we need to refactor that code in the future.
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit 1ce87720d4 ("net: sched: make cls_u32 lockless")
we began to release tc actions in a RCU callback. However,
mirred action relies on RTNL lock to protect the global
mirred_list, therefore we could have a race condition
between RCU callback and netdevice event, which caused
a list corruption as reported by Vinson.
Instead of relying on RTNL lock, introduce a spinlock to
protect this list.
Note, in non-bind case, it is still called with RTNL lock,
therefore should disable BH too.
Reported-by: Vinson Lee <vlee@twopensource.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/net/ethernet/cavium/Kconfig
The cavium conflict was overlapping dependency
changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
Like act_gact, act_mirred can be lockless in packet processing
1) Use percpu stats
2) update lastuse only every clock tick to avoid false sharing
3) use rcu to protect tcfm_dev
4) Remove spinlock usage, as it is no longer needed.
Next step : add multi queue capability to ifb device
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reuse existing percpu infrastructure John Fastabend added for qdisc.
This patch adds a new cpustats parameter to tcf_hash_create() and all
actions pass false, meaning this patch should have no effect yet.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Seems all we want here is to avoid endless 'goto reclassify' loop.
tc_classify_compat even resets this counter when something other
than TC_ACT_RECLASSIFY is returned, so this skb-counter doesn't
break hypothetical loops induced by something other than perpetual
TC_ACT_RECLASSIFY return values.
skb_act_clone is now identical to skb_clone, so just use that.
Tested with following (bogus) filter:
tc filter add dev eth0 parent ffff: \
protocol ip u32 match u32 0 0 police rate 10Kbit burst \
64000 mtu 1500 action reclassify
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When you redirect a VLAN device to any device, you end up with
crap in af_packet on the xmit path because hard_header_len is
not equal to skb->mac_len. So the redirected packet contains
four extra bytes at the start which then gets interpreted as
part of the MAC address.
This patch fixes this by only pushing skb->mac_len. We also
need to fix ifb because it tries to undo the pushing done by
act_mirred.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We modify mirred action (m->tcfm_dev) in netdev event, we need to
prevent on-going mirred actions from reading freed m->tcfm_dev.
So we need to acquire this spin lock.
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For bindcnt and refcnt etc., they are common for all actions,
not need to repeat such operations for their own, they can be unified
now. Actions just need to do its specific cleanup if needed.
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now we can totally hide it from modules. tcf_hash_*() API's
will operate on struct tc_action, modules don't need to care about
the details.
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
WANG Cong
David S. Miller
Jamal Hadi Salim
Nicolas Dichtel
Eric Dumazet
Florian Westphal
Herbert Xu
Jiri Pirko
Cong Wang