Modify the kernel users of the TCA_ACT_* macros to use TCA_ID_*. For
example, use TCA_ID_GACT instead of TCA_ACT_GACT. This will align with
TCA_ID_POLICE and also differentiates these identifier, used in struct
tc_action_ops type field, from other macros starting with TCA_ACT_.

To make things clearer, we name the enum defining the TCA_ID_*
identifiers and also change the "type" field of struct tc_action to
id.
Signed-off-by: NEli Cohen <eli@mellanox.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

when users set an invalid control action, kmemleak complains as follows:

 # echo clear >/sys/kernel/debug/kmemleak
 # ./tdc.py -e b48b
 Test b48b: Add police action with exceed goto chain control action
 All test results:

 1..1
 ok 1 - b48b # Add police action with exceed goto chain control action
 about to flush the tap output if tests need to be skipped
 done flushing skipped test tap output
 # echo scan >/sys/kernel/debug/kmemleak
 # cat /sys/kernel/debug/kmemleak
 unreferenced object 0xffffa0fafbc3dde0 (size 96):
  comm "tc", pid 2358, jiffies 4294922738 (age 17.022s)
  hex dump (first 32 bytes):
    2a 00 00 20 00 00 00 00 00 00 7d 00 00 00 00 00  *.. ......}.....
    f8 07 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<00000000648803d2>] tcf_action_init_1+0x384/0x4c0
    [<00000000cb69382e>] tcf_action_init+0x12b/0x1a0
    [<00000000847ef0d4>] tcf_action_add+0x73/0x170
    [<0000000093656e14>] tc_ctl_action+0x122/0x160
    [<0000000023c98e32>] rtnetlink_rcv_msg+0x263/0x2d0
    [<000000003493ae9c>] netlink_rcv_skb+0x4d/0x130
    [<00000000de63f8ba>] netlink_unicast+0x209/0x2d0
    [<00000000c3da0ebe>] netlink_sendmsg+0x2c1/0x3c0
    [<000000007a9e0753>] sock_sendmsg+0x33/0x40
    [<00000000457c6d2e>] ___sys_sendmsg+0x2a0/0x2f0
    [<00000000c5c6a086>] __sys_sendmsg+0x5e/0xa0
    [<00000000446eafce>] do_syscall_64+0x5b/0x180
    [<000000004aa871f2>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
    [<00000000450c38ef>] 0xffffffffffffffff

change tcf_police_init() to avoid leaking 'new' in case TCA_POLICE_RESULT
contains TC_ACT_GOTO_CHAIN extended action.

Fixes: c08f5ed5 ("net/sched: act_police: disallow 'goto chain' on fallback control action")
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavide Caratti <dcaratti@redhat.com>
Acked-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit f2cbd485 ("net/sched: act_police: fix race condition on state
variables") introduces a new spinlock, but forgets its initialization.
Ensure that tcf_police_init() initializes 'tcfp_lock' every time a 'police'
action is newly created, to avoid the following lockdep splat:

 INFO: trying to register non-static key.
 the code is fine but needs lockdep annotation.
 turning off the locking correctness validator.
 <...>
 Call Trace:
  dump_stack+0x85/0xcb
  register_lock_class+0x581/0x590
  __lock_acquire+0xd4/0x1330
  ? tcf_police_init+0x2fa/0x650 [act_police]
  ? lock_acquire+0x9e/0x1a0
  lock_acquire+0x9e/0x1a0
  ? tcf_police_init+0x2fa/0x650 [act_police]
  ? tcf_police_init+0x55a/0x650 [act_police]
  _raw_spin_lock_bh+0x34/0x40
  ? tcf_police_init+0x2fa/0x650 [act_police]
  tcf_police_init+0x2fa/0x650 [act_police]
  tcf_action_init_1+0x384/0x4c0
  tcf_action_init+0xf6/0x160
  tcf_action_add+0x73/0x170
  tc_ctl_action+0x122/0x160
  rtnetlink_rcv_msg+0x2a4/0x490
  ? netlink_deliver_tap+0x99/0x400
  ? validate_linkmsg+0x370/0x370
  netlink_rcv_skb+0x4d/0x130
  netlink_unicast+0x196/0x230
  netlink_sendmsg+0x2e5/0x3e0
  sock_sendmsg+0x36/0x40
  ___sys_sendmsg+0x280/0x2f0
  ? _raw_spin_unlock+0x24/0x30
  ? handle_pte_fault+0xafe/0xf30
  ? find_held_lock+0x2d/0x90
  ? syscall_trace_enter+0x1df/0x360
  ? __sys_sendmsg+0x5e/0xa0
  __sys_sendmsg+0x5e/0xa0
  do_syscall_64+0x60/0x210
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
 RIP: 0033:0x7f1841c7cf10
 Code: c3 48 8b 05 82 6f 2c 00 f7 db 64 89 18 48 83 cb ff eb dd 0f 1f 80 00 00 00 00 83 3d 8d d0 2c 00 00 75 10 b8 2e 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 ae cc 00 00 48 89 04 24
 RSP: 002b:00007ffcf9df4d68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 RAX: ffffffffffffffda RBX: 0000000000000001 RCX: 00007f1841c7cf10
 RDX: 0000000000000000 RSI: 00007ffcf9df4dc0 RDI: 0000000000000003
 RBP: 000000005bf56105 R08: 0000000000000002 R09: 00007ffcf9df8edc
 R10: 00007ffcf9df47e0 R11: 0000000000000246 R12: 0000000000671be0
 R13: 00007ffcf9df4e84 R14: 0000000000000008 R15: 0000000000000000

Fixes: f2cbd485 ("net/sched: act_police: fix race condition on state variables")
Reported-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavide Caratti <dcaratti@redhat.com>
Acked-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

after 'police' configuration parameters were converted to use RCU instead
of spinlock, the state variables used to compute the traffic rate (namely
'tcfp_toks', 'tcfp_ptoks' and 'tcfp_t_c') are erroneously read/updated in
the traffic path without any protection.

Use a dedicated spinlock to avoid race conditions on these variables, and
ensure proper cache-line alignment. In this way, 'police' is still faster
than what we observed when 'tcf_lock' was used in the traffic path _ i.e.
reverting commit 2d550dba ("net/sched: act_police: don't use spinlock
in the data path"). Moreover, we preserve the throughput improvement that
was obtained after 'police' started using per-cpu counters, when 'avrate'
is used instead of 'rate'.

Changes since v1 (thanks to Eric Dumazet):
- call ktime_get_ns() before acquiring the lock in the traffic path
- use a dedicated spinlock instead of tcf_lock
- improve cache-line usage

Fixes: 2d550dba ("net/sched: act_police: don't use spinlock in the data path")
Reported-and-suggested-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavide Caratti <dcaratti@redhat.com>
Reviewed-by: NEric Dumazet <edumazet@google.com>

in the following command:

 # tc action add action police rate <r> burst <b> conform-exceed <c1>/<c2>

'goto chain x' is allowed only for c1: setting it for c2 makes the kernel
crash with NULL pointer dereference, since TC core doesn't initialize the
chain handle.
Signed-off-by: NDavide Caratti <dcaratti@redhat.com>
Acked-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

use RCU instead of spinlocks, to protect concurrent read/write on
act_police configuration. This reduces the effects of contention in the
data path, in case multiple readers are present.
Signed-off-by: NDavide Caratti <dcaratti@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

use per-CPU counters, instead of sharing a single set of stats with all
cores. This removes the need of using spinlock when statistics are read
or updated.
Signed-off-by: NDavide Caratti <dcaratti@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit 331a9295 ("net: sched: act: add extack for lookup callback").

This extack is never used after 6 months... In fact, it can be just
set in the caller, right after ->lookup().

Cc: Alexander Aring <aring@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

All ops->delete() wants is getting the tn->idrinfo, but we already
have tc_action before calling ops->delete(), and tc_action has
a pointer ->idrinfo.

More importantly, each type of action does the same thing, that is,
just calling tcf_idr_delete_index().

So it can be just removed.

Fixes: b409074e ("net: sched: add 'delete' function to action ops")
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Vlad Buslov <vladbu@mellanox.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use tcf spinlock to protect police action private data from concurrent
modification during dump. (init already uses tcf spinlock when changing
police action state)

Pass tcf spinlock as estimator lock argument to gen_replace_estimator()
during action init.
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Implement function that atomically checks if action exists and either takes
reference to it, or allocates idr slot for action index to prevent
concurrent allocations of actions with same index. Use EBUSY error pointer
to indicate that idr slot is reserved.

Implement cleanup helper function that removes temporary error pointer from
idr. (in case of error between idr allocation and insertion of newly
created action to specified index)

Refactor all action init functions to insert new action to idr using this
API.
Reviewed-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Return from action init function with reference to action taken,
even when overwriting existing action.

Action init API initializes its fourth argument (pointer to pointer to tc
action) to either existing action with same index or newly created action.
In case of existing index(and bind argument is zero), init function returns
without incrementing action reference counter. Caller of action init then
proceeds working with action, without actually holding reference to it.
This means that action could be deleted concurrently.

Change action init behavior to always take reference to action before
returning successfully, in order to protect from concurrent deletion.
Reviewed-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Extend action ops with 'delete' function. Each action type to implements
its own delete function that doesn't depend on rtnl lock.

Implement delete function that is required to delete actions without
holding rtnl lock. Use action API function that atomically deletes action
only if it is still in action idr. This implementation prevents concurrent
threads from deleting same action twice.
Reviewed-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add additional 'rtnl_held' argument to act API init functions. It is
required to implement actions that need to release rtnl lock before loading
kernel module and reacquire if afterwards.
Reviewed-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Change type of action reference counter to refcount_t.

Change type of action bind counter to atomic_t.
This type is used to allow decrementing bind counter without testing
for 0 result.
Reviewed-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NVlad Buslov <vladbu@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

tcf_act_police_init() can fail after the idr has been successfully
reserved (e.g., qdisc_get_rtab() may return NULL). When this happens,
subsequent attempts to configure a police rule using the same idr value
systematiclly fail with -ENOSPC:

 # tc action add action police rate 1000 burst 1000 drop index 100
 RTNETLINK answers: Cannot allocate memory
 We have an error talking to the kernel
 # tc action add action police rate 1000 burst 1000 drop index 100
 RTNETLINK answers: No space left on device
 We have an error talking to the kernel
 # tc action add action police rate 1000 burst 1000 drop index 100
 RTNETLINK answers: No space left on device
 ...

Fix this in the error path of tcf_act_police_init(), calling
tcf_idr_release() in place of tcf_idr_cleanup().

Fixes: 65a206c0 ("net/sched: Change act_api and act_xxx modules to use IDR")
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavide Caratti <dcaratti@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These pernet_operations are from net/sched directory, and they call only
tc_action_net_init() and tc_action_net_exit():

bpf_net_ops
connmark_net_ops
csum_net_ops
gact_net_ops
ife_net_ops
ipt_net_ops
xt_net_ops
mirred_net_ops
nat_net_ops
pedit_net_ops
police_net_ops
sample_net_ops
simp_net_ops
skbedit_net_ops
skbmod_net_ops
tunnel_key_net_ops
vlan_net_ops

1)tc_action_net_init() just allocates and initializes per-net memory.
2)There should not be in-flight packets at the time of tc_action_net_exit()
call, or another pernet_operations send packets to dying net (except
netlink). So, it seems they can be marked as async.
Signed-off-by: NKirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds extack handling for a common used TC act function
"tcf_generic_walker()" to add an extack message on failures.
The tcf_generic_walker() function can fail if get a invalid command
different than DEL and GET. The naming "action" here is wrong, the
correct naming would be command.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds extack support for act walker callback api. This
prepares to handle extack support inside each specific act
implementation.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds extack support for act lookup callback api. This
prepares to handle extack support inside each specific act
implementation.

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds extack support for act init callback api. This
prepares to handle extack support inside each specific act
implementation.

Based on work by David Ahern <dsahern@gmail.com>

Cc: David Ahern <dsahern@gmail.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds extack support for the function qdisc_get_rtab which is
a common used function in the tc subsystem. Callers which are interested
in the receiving error can assign extack to get a more detailed
information why qdisc_get_rtab failed.

Cc: David Ahern <dsahern@gmail.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NAlexander Aring <aring@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since we now hold RTNL lock in tc_action_net_exit(), it is good to
batch them to speedup tc action dismantle.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit ceffcc5e.
If we hold that refcnt, the netns can never be destroyed until
all actions are destroyed by user, this breaks our netns design
which we expect all actions are destroyed when we destroy the
whole netns.

Cc: Lucas Bates <lucasb@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

TC actions have been destroyed asynchronously for a long time,
previously in a RCU callback and now in a workqueue. If we
don't hold a refcnt for its netns, we could use the per netns
data structure, struct tcf_idrinfo, after it has been freed by
netns workqueue.

Hold refcnt to ensure netns destroy happens after all actions
are gone.

Fixes: ddf97ccd ("net_sched: add network namespace support for tc actions")
Reported-by: NLucas Bates <lucasb@mojatatu.com>
Tested-by: NLucas Bates <lucasb@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Typically, each TC filter has its own action. All the actions of the
same type are saved in its hash table. But the hash buckets are too
small that it degrades to a list. And the performance is greatly
affected. For example, it takes about 0m11.914s to insert 64K rules.
If we convert the hash table to IDR, it only takes about 0m1.500s.
The improvement is huge.

But please note that the test result is based on previous patch that
cls_flower uses IDR.
Signed-off-by: NChris Mi <chrism@mellanox.com>
Signed-off-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Laura reported a sleep-in-atomic kernel warning inside
tcf_act_police_init() which calls gen_replace_estimator() with
spinlock protection.

It is not necessary in this case, we already have RTNL lock here
so it is enough to protect concurrent writers. For the reader,
i.e. tcf_act_police(), it needs to make decision based on this
rate estimator, in the worst case we drop more/less packets than
necessary while changing the rate in parallel, it is still acceptable.
Reported-by: NLaura Abbott <labbott@redhat.com>
Reported-by: NNick Huber <nicholashuber@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

1) Old code was hard to maintain, due to complex lock chains.
   (We probably will be able to remove some kfree_rcu() in callers)

2) Using a single timer to update all estimators does not scale.

3) Code was buggy on 32bit kernel (WRITE_ONCE() on 64bit quantity
   is not supposed to work well)

In this rewrite :

- I removed the RB tree that had to be scanned in
  gen_estimator_active(). qdisc dumps should be much faster.

- Each estimator has its own timer.

- Estimations are maintained in net_rate_estimator structure,
  instead of dirtying the qdisc. Minor, but part of the simplification.

- Reading the estimator uses RCU and a seqcount to provide proper
  support for 32bit kernels.

- We reduce memory need when estimators are not used, since
  we store a pointer, instead of the bytes/packets counters.

- xt_rateest_mt() no longer has to grab a spinlock.
  (In the future, xt_rateest_tg() could be switched to per cpu counters)
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make struct pernet_operations::id unsigned.

There are 2 reasons to do so:

1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.

2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.

"int" being used as an array index needs to be sign-extended
to 64-bit before being used.

	void f(long *p, int i)
	{
		g(p[i]);
	}

  roughly translates to

	movsx	rsi, esi
	mov	rdi, [rsi+...]
	call 	g

MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.

Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:

	static inline void *net_generic(const struct net *net, int id)
	{
		...
		ptr = ng->ptr[id - 1];
		...
	}

And this function is used a lot, so those sign extensions add up.

Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)

Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]

However, overall balance is in negative direction:

	add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
	function                                     old     new   delta
	nfsd4_lock                                  3886    3959     +73
	tipc_link_build_proto_msg                   1096    1140     +44
	mac80211_hwsim_new_radio                    2776    2808     +32
	tipc_mon_rcv                                1032    1058     +26
	svcauth_gss_legacy_init                     1413    1429     +16
	tipc_bcbase_select_primary                   379     392     +13
	nfsd4_exchange_id                           1247    1260     +13
	nfsd4_setclientid_confirm                    782     793     +11
		...
	put_client_renew_locked                      494     480     -14
	ip_set_sockfn_get                            730     716     -14
	geneve_sock_add                              829     813     -16
	nfsd4_sequence_done                          721     703     -18
	nlmclnt_lookup_host                          708     686     -22
	nfsd4_lockt                                 1085    1063     -22
	nfs_get_client                              1077    1050     -27
	tcf_bpf_init                                1106    1076     -30
	nfsd4_encode_fattr                          5997    5930     -67
	Total: Before=154856051, After=154854321, chg -0.00%
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

setting conforming action to drop is a valid policy.
When it is set we need to at least see the stats indicating it
for debugging.
Signed-off-by: NRoman Mashak <mrv@mojatatu.com>
Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The act_police uses its own code to walk the
action hashtable, which leads to that we could
not flush standalone tc police actions, so just
switch to tcf_generic_walker() like other actions.

(Joint work from Roman and Cong.)
Signed-off-by: NRoman Mashak <mrv@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Jamal reported a crash when we create a police action
with a specific index, this is because the init logic
is not correct, we should always create one for this
case. Just unify the logic with other tc actions.

Fixes: a03e6fe5 ("act_police: fix a crash during removal")
Reported-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After the previous patch, struct tc_action should be enough
to represent the generic tc action, tcf_common is not necessary
any more. This patch gets rid of it to make tc action code
more readable.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

struct tc_action is confusing, currently we use it for two purposes:
1) Pass in arguments and carry out results from helper functions
2) A generic representation for tc actions

The first one is error-prone, since we need to make sure we don't
miss anything. This patch aims to get rid of this use, by moving
tc_action into tcf_common, so that they are allocated together
in hashtable and can be cast'ed easily.

And together with the following patch, we could really make
tc_action a generic representation for all tc actions and each
type of action can inherit from it.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This function is just ->init(), rename it to make it obvious.

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The police action is using its own code to initialize tcf hash
info, which makes us to forgot to initialize a->hinfo correctly.
Fix this by calling the helper function tcf_hash_create() directly.

This patch fixed the following crash:

 BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
 IP: [<ffffffff810c099f>] __lock_acquire+0xd3/0xf91
 PGD d3c34067 PUD d3e18067 PMD 0
 Oops: 0000 [#1] SMP
 CPU: 2 PID: 853 Comm: tc Not tainted 4.6.0+ #87
 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
 task: ffff8800d3e28040 ti: ffff8800d3f6c000 task.ti: ffff8800d3f6c000
 RIP: 0010:[<ffffffff810c099f>]  [<ffffffff810c099f>] __lock_acquire+0xd3/0xf91
 RSP: 0000:ffff88011b203c80  EFLAGS: 00010002
 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000028
 RBP: ffff88011b203d40 R08: 0000000000000001 R09: 0000000000000000
 R10: ffff88011b203d58 R11: ffff88011b208000 R12: 0000000000000001
 R13: ffff8800d3e28040 R14: 0000000000000028 R15: 0000000000000000
 FS:  0000000000000000(0000) GS:ffff88011b200000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000000000000028 CR3: 00000000d4be1000 CR4: 00000000000006e0
 Stack:
  ffff8800d3e289c0 0000000000000046 000000001b203d60 ffffffff00000000
  0000000000000000 ffff880000000000 0000000000000000 ffffffff00000000
  ffffffff8187142c ffff88011b203ce8 ffff88011b203ce8 ffffffff8101dbfc
 Call Trace:
  <IRQ>
  [<ffffffff8187142c>] ? __tcf_hash_release+0x77/0xd1
  [<ffffffff8101dbfc>] ? native_sched_clock+0x1a/0x35
  [<ffffffff8101dbfc>] ? native_sched_clock+0x1a/0x35
  [<ffffffff810a9604>] ? sched_clock_local+0x11/0x78
  [<ffffffff810bf6a1>] ? mark_lock+0x24/0x201
  [<ffffffff810c1dbd>] lock_acquire+0x120/0x1b4
  [<ffffffff810c1dbd>] ? lock_acquire+0x120/0x1b4
  [<ffffffff8187142c>] ? __tcf_hash_release+0x77/0xd1
  [<ffffffff81aad89f>] _raw_spin_lock_bh+0x3c/0x72
  [<ffffffff8187142c>] ? __tcf_hash_release+0x77/0xd1
  [<ffffffff8187142c>] __tcf_hash_release+0x77/0xd1
  [<ffffffff81871a27>] tcf_action_destroy+0x49/0x7c
  [<ffffffff81870b1c>] tcf_exts_destroy+0x20/0x2d
  [<ffffffff8189273b>] u32_destroy_key+0x1b/0x4d
  [<ffffffff81892788>] u32_delete_key_freepf_rcu+0x1b/0x1d
  [<ffffffff810de3b8>] rcu_process_callbacks+0x610/0x82e
  [<ffffffff8189276d>] ? u32_destroy_key+0x4d/0x4d
  [<ffffffff81ab0bc1>] __do_softirq+0x191/0x3f4

Fixes: ddf97ccd ("net_sched: add network namespace support for tc actions")
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>