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270 commits

Author SHA1 Message Date
Eric Dumazet d5d20912d3 netfilter: conntrack: Fix UP builds
ARRAY_SIZE(nf_conntrack_locks) is undefined if spinlock_t is an
empty structure. Replace it by CONNTRACK_LOCKS

Fixes: 93bb0ceb75 ("netfilter: conntrack: remove central spinlock nf_conntrack_lock")
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-17 17:14:45 -04:00
Jesper Dangaard Brouer 93bb0ceb75 netfilter: conntrack: remove central spinlock nf_conntrack_lock
nf_conntrack_lock is a monolithic lock and suffers from huge contention
on current generation servers (8 or more core/threads).

Perf locking congestion is clear on base kernel:

-  72.56%  ksoftirqd/6  [kernel.kallsyms]    [k] _raw_spin_lock_bh
   - _raw_spin_lock_bh
      + 25.33% init_conntrack
      + 24.86% nf_ct_delete_from_lists
      + 24.62% __nf_conntrack_confirm
      + 24.38% destroy_conntrack
      + 0.70% tcp_packet
+   2.21%  ksoftirqd/6  [kernel.kallsyms]    [k] fib_table_lookup
+   1.15%  ksoftirqd/6  [kernel.kallsyms]    [k] __slab_free
+   0.77%  ksoftirqd/6  [kernel.kallsyms]    [k] inet_getpeer
+   0.70%  ksoftirqd/6  [nf_conntrack]       [k] nf_ct_delete
+   0.55%  ksoftirqd/6  [ip_tables]          [k] ipt_do_table

This patch change conntrack locking and provides a huge performance
improvement.  SYN-flood attack tested on a 24-core E5-2695v2(ES) with
10Gbit/s ixgbe (with tool trafgen):

 Base kernel:   810.405 new conntrack/sec
 After patch: 2.233.876 new conntrack/sec

Notice other floods attack (SYN+ACK or ACK) can easily be deflected using:
 # iptables -A INPUT -m state --state INVALID -j DROP
 # sysctl -w net/netfilter/nf_conntrack_tcp_loose=0

Use an array of hashed spinlocks to protect insertions/deletions of
conntracks into the hash table. 1024 spinlocks seem to give good
results, at minimal cost (4KB memory). Due to lockdep max depth,
1024 becomes 8 if CONFIG_LOCKDEP=y

The hash resize is a bit tricky, because we need to take all locks in
the array. A seqcount_t is used to synchronize the hash table users
with the resizing process.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-03-07 11:41:13 +01:00
Jesper Dangaard Brouer ca7433df3a netfilter: conntrack: seperate expect locking from nf_conntrack_lock
Netfilter expectations are protected with the same lock as conntrack
entries (nf_conntrack_lock).  This patch split out expectations locking
to use it's own lock (nf_conntrack_expect_lock).

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-03-07 11:41:01 +01:00
Jesper Dangaard Brouer e1b207dac1 netfilter: avoid race with exp->master ct
Preparation for disconnecting the nf_conntrack_lock from the
expectations code.  Once the nf_conntrack_lock is lifted, a race
condition is exposed.

The expectations master conntrack exp->master, can race with
delete operations, as the refcnt increment happens too late in
init_conntrack().  Race is against other CPUs invoking
->destroy() (destroy_conntrack()), or nf_ct_delete() (via timeout
or early_drop()).

Avoid this race in nf_ct_find_expectation() by using atomic_inc_not_zero(),
and checking if nf_ct_is_dying() (path via nf_ct_delete()).

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-03-07 11:40:47 +01:00
Jesper Dangaard Brouer b7779d06f9 netfilter: conntrack: spinlock per cpu to protect special lists.
One spinlock per cpu to protect dying/unconfirmed/template special lists.
(These lists are now per cpu, a bit like the untracked ct)
Add a @cpu field to nf_conn, to make sure we hold the appropriate
spinlock at removal time.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-03-07 11:40:38 +01:00
Jesper Dangaard Brouer b476b72a0f netfilter: trivial code cleanup and doc changes
Changes while reading through the netfilter code.

Added hint about how conntrack nf_conn refcnt is accessed.
And renamed repl_hash to reply_hash for readability

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-03-07 11:40:04 +01:00
Pablo Neira Ayuso e53376bef2 netfilter: nf_conntrack: don't release a conntrack with non-zero refcnt
With this patch, the conntrack refcount is initially set to zero and
it is bumped once it is added to any of the list, so we fulfill
Eric's golden rule which is that all released objects always have a
refcount that equals zero.

Andrey Vagin reports that nf_conntrack_free can't be called for a
conntrack with non-zero ref-counter, because it can race with
nf_conntrack_find_get().

A conntrack slab is created with SLAB_DESTROY_BY_RCU. Non-zero
ref-counter says that this conntrack is used. So when we release
a conntrack with non-zero counter, we break this assumption.

CPU1                                    CPU2
____nf_conntrack_find()
                                        nf_ct_put()
                                         destroy_conntrack()
                                        ...
                                        init_conntrack
                                         __nf_conntrack_alloc (set use = 1)
atomic_inc_not_zero(&ct->use) (use = 2)
                                         if (!l4proto->new(ct, skb, dataoff, timeouts))
                                          nf_conntrack_free(ct); (use = 2 !!!)
                                        ...
                                        __nf_conntrack_alloc (set use = 1)
 if (!nf_ct_key_equal(h, tuple, zone))
  nf_ct_put(ct); (use = 0)
   destroy_conntrack()
                                        /* continue to work with CT */

After applying the path "[PATCH] netfilter: nf_conntrack: fix RCU
race in nf_conntrack_find_get" another bug was triggered in
destroy_conntrack():

<4>[67096.759334] ------------[ cut here ]------------
<2>[67096.759353] kernel BUG at net/netfilter/nf_conntrack_core.c:211!
...
<4>[67096.759837] Pid: 498649, comm: atdd veid: 666 Tainted: G         C ---------------    2.6.32-042stab084.18 #1 042stab084_18 /DQ45CB
<4>[67096.759932] RIP: 0010:[<ffffffffa03d99ac>]  [<ffffffffa03d99ac>] destroy_conntrack+0x15c/0x190 [nf_conntrack]
<4>[67096.760255] Call Trace:
<4>[67096.760255]  [<ffffffff814844a7>] nf_conntrack_destroy+0x17/0x30
<4>[67096.760255]  [<ffffffffa03d9bb5>] nf_conntrack_find_get+0x85/0x130 [nf_conntrack]
<4>[67096.760255]  [<ffffffffa03d9fb2>] nf_conntrack_in+0x352/0xb60 [nf_conntrack]
<4>[67096.760255]  [<ffffffffa048c771>] ipv4_conntrack_local+0x51/0x60 [nf_conntrack_ipv4]
<4>[67096.760255]  [<ffffffff81484419>] nf_iterate+0x69/0xb0
<4>[67096.760255]  [<ffffffff814b5b00>] ? dst_output+0x0/0x20
<4>[67096.760255]  [<ffffffff814845d4>] nf_hook_slow+0x74/0x110
<4>[67096.760255]  [<ffffffff814b5b00>] ? dst_output+0x0/0x20
<4>[67096.760255]  [<ffffffff814b66d5>] raw_sendmsg+0x775/0x910
<4>[67096.760255]  [<ffffffff8104c5a8>] ? flush_tlb_others_ipi+0x128/0x130
<4>[67096.760255]  [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20
<4>[67096.760255]  [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20
<4>[67096.760255]  [<ffffffff814c136a>] inet_sendmsg+0x4a/0xb0
<4>[67096.760255]  [<ffffffff81444e93>] ? sock_sendmsg+0x13/0x140
<4>[67096.760255]  [<ffffffff81444f97>] sock_sendmsg+0x117/0x140
<4>[67096.760255]  [<ffffffff8102e299>] ? native_smp_send_reschedule+0x49/0x60
<4>[67096.760255]  [<ffffffff81519beb>] ? _spin_unlock_bh+0x1b/0x20
<4>[67096.760255]  [<ffffffff8109d930>] ? autoremove_wake_function+0x0/0x40
<4>[67096.760255]  [<ffffffff814960f0>] ? do_ip_setsockopt+0x90/0xd80
<4>[67096.760255]  [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20
<4>[67096.760255]  [<ffffffff8100bc4e>] ? apic_timer_interrupt+0xe/0x20
<4>[67096.760255]  [<ffffffff814457c9>] sys_sendto+0x139/0x190
<4>[67096.760255]  [<ffffffff810efa77>] ? audit_syscall_entry+0x1d7/0x200
<4>[67096.760255]  [<ffffffff810ef7c5>] ? __audit_syscall_exit+0x265/0x290
<4>[67096.760255]  [<ffffffff81474daf>] compat_sys_socketcall+0x13f/0x210
<4>[67096.760255]  [<ffffffff8104dea3>] ia32_sysret+0x0/0x5

I have reused the original title for the RFC patch that Andrey posted and
most of the original patch description.

Cc: Eric Dumazet <edumazet@google.com>
Cc: Andrew Vagin <avagin@parallels.com>
Cc: Florian Westphal <fw@strlen.de>
Reported-by: Andrew Vagin <avagin@parallels.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Andrew Vagin <avagin@parallels.com>
2014-02-05 17:46:06 +01:00
Andrey Vagin c6825c0976 netfilter: nf_conntrack: fix RCU race in nf_conntrack_find_get
Lets look at destroy_conntrack:

hlist_nulls_del_rcu(&ct->tuplehash[IP_CT_DIR_ORIGINAL].hnnode);
...
nf_conntrack_free(ct)
	kmem_cache_free(net->ct.nf_conntrack_cachep, ct);

net->ct.nf_conntrack_cachep is created with SLAB_DESTROY_BY_RCU.

The hash is protected by rcu, so readers look up conntracks without
locks.
A conntrack is removed from the hash, but in this moment a few readers
still can use the conntrack. Then this conntrack is released and another
thread creates conntrack with the same address and the equal tuple.
After this a reader starts to validate the conntrack:
* It's not dying, because a new conntrack was created
* nf_ct_tuple_equal() returns true.

But this conntrack is not initialized yet, so it can not be used by two
threads concurrently. In this case BUG_ON may be triggered from
nf_nat_setup_info().

Florian Westphal suggested to check the confirm bit too. I think it's
right.

task 1			task 2			task 3
			nf_conntrack_find_get
			 ____nf_conntrack_find
destroy_conntrack
 hlist_nulls_del_rcu
 nf_conntrack_free
 kmem_cache_free
						__nf_conntrack_alloc
						 kmem_cache_alloc
						 memset(&ct->tuplehash[IP_CT_DIR_MAX],
			 if (nf_ct_is_dying(ct))
			 if (!nf_ct_tuple_equal()

I'm not sure, that I have ever seen this race condition in a real life.
Currently we are investigating a bug, which is reproduced on a few nodes.
In our case one conntrack is initialized from a few tasks concurrently,
we don't have any other explanation for this.

<2>[46267.083061] kernel BUG at net/ipv4/netfilter/nf_nat_core.c:322!
...
<4>[46267.083951] RIP: 0010:[<ffffffffa01e00a4>]  [<ffffffffa01e00a4>] nf_nat_setup_info+0x564/0x590 [nf_nat]
...
<4>[46267.085549] Call Trace:
<4>[46267.085622]  [<ffffffffa023421b>] alloc_null_binding+0x5b/0xa0 [iptable_nat]
<4>[46267.085697]  [<ffffffffa02342bc>] nf_nat_rule_find+0x5c/0x80 [iptable_nat]
<4>[46267.085770]  [<ffffffffa0234521>] nf_nat_fn+0x111/0x260 [iptable_nat]
<4>[46267.085843]  [<ffffffffa0234798>] nf_nat_out+0x48/0xd0 [iptable_nat]
<4>[46267.085919]  [<ffffffff814841b9>] nf_iterate+0x69/0xb0
<4>[46267.085991]  [<ffffffff81494e70>] ? ip_finish_output+0x0/0x2f0
<4>[46267.086063]  [<ffffffff81484374>] nf_hook_slow+0x74/0x110
<4>[46267.086133]  [<ffffffff81494e70>] ? ip_finish_output+0x0/0x2f0
<4>[46267.086207]  [<ffffffff814b5890>] ? dst_output+0x0/0x20
<4>[46267.086277]  [<ffffffff81495204>] ip_output+0xa4/0xc0
<4>[46267.086346]  [<ffffffff814b65a4>] raw_sendmsg+0x8b4/0x910
<4>[46267.086419]  [<ffffffff814c10fa>] inet_sendmsg+0x4a/0xb0
<4>[46267.086491]  [<ffffffff814459aa>] ? sock_update_classid+0x3a/0x50
<4>[46267.086562]  [<ffffffff81444d67>] sock_sendmsg+0x117/0x140
<4>[46267.086638]  [<ffffffff8151997b>] ? _spin_unlock_bh+0x1b/0x20
<4>[46267.086712]  [<ffffffff8109d370>] ? autoremove_wake_function+0x0/0x40
<4>[46267.086785]  [<ffffffff81495e80>] ? do_ip_setsockopt+0x90/0xd80
<4>[46267.086858]  [<ffffffff8100be0e>] ? call_function_interrupt+0xe/0x20
<4>[46267.086936]  [<ffffffff8118cb10>] ? ub_slab_ptr+0x20/0x90
<4>[46267.087006]  [<ffffffff8118cb10>] ? ub_slab_ptr+0x20/0x90
<4>[46267.087081]  [<ffffffff8118f2e8>] ? kmem_cache_alloc+0xd8/0x1e0
<4>[46267.087151]  [<ffffffff81445599>] sys_sendto+0x139/0x190
<4>[46267.087229]  [<ffffffff81448c0d>] ? sock_setsockopt+0x16d/0x6f0
<4>[46267.087303]  [<ffffffff810efa47>] ? audit_syscall_entry+0x1d7/0x200
<4>[46267.087378]  [<ffffffff810ef795>] ? __audit_syscall_exit+0x265/0x290
<4>[46267.087454]  [<ffffffff81474885>] ? compat_sys_setsockopt+0x75/0x210
<4>[46267.087531]  [<ffffffff81474b5f>] compat_sys_socketcall+0x13f/0x210
<4>[46267.087607]  [<ffffffff8104dea3>] ia32_sysret+0x0/0x5
<4>[46267.087676] Code: 91 20 e2 01 75 29 48 89 de 4c 89 f7 e8 56 fa ff ff 85 c0 0f 84 68 fc ff ff 0f b6 4d c6 41 8b 45 00 e9 4d fb ff ff e8 7c 19 e9 e0 <0f> 0b eb fe f6 05 17 91 20 e2 80 74 ce 80 3d 5f 2e 00 00 00 74
<1>[46267.088023] RIP  [<ffffffffa01e00a4>] nf_nat_setup_info+0x564/0x590

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Florian Westphal <fw@strlen.de>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-02-05 13:16:18 +01:00
stephen hemminger dcd93ed4cd netfilter: nf_conntrack: remove dead code
The following code is not used in current upstream code.
Some of this seems to be old hooks, other might be used by some
out of tree module (which I don't care about breaking), and
the need_ipv4_conntrack was used by old NAT code but no longer
called.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-01-03 23:41:37 +01:00
Pablo Neira Ayuso 0c3c6c00c6 netfilter: nf_conntrack: decrement global counter after object release
nf_conntrack_free() decrements our counter (net->ct.count)
before releasing the conntrack object. That counter is used in the
nf_conntrack_cleanup_net_list path to check if it's time to
kmem_cache_destroy our cache of conntrack objects. I think we have
a race there that should be easier to trigger (although still hard)
with CONFIG_DEBUG_OBJECTS_FREE as object releases become slowier
according to the following splat:

[ 1136.321305] WARNING: CPU: 2 PID: 2483 at lib/debugobjects.c:260
debug_print_object+0x83/0xa0()
[ 1136.321311] ODEBUG: free active (active state 0) object type:
timer_list hint: delayed_work_timer_fn+0x0/0x20
...
[ 1136.321390] Call Trace:
[ 1136.321398]  [<ffffffff8160d4a2>] dump_stack+0x45/0x56
[ 1136.321405]  [<ffffffff810514e8>] warn_slowpath_common+0x78/0xa0
[ 1136.321410]  [<ffffffff81051557>] warn_slowpath_fmt+0x47/0x50
[ 1136.321414]  [<ffffffff812f8883>] debug_print_object+0x83/0xa0
[ 1136.321420]  [<ffffffff8106aa90>] ? execute_in_process_context+0x90/0x90
[ 1136.321424]  [<ffffffff812f99fb>] debug_check_no_obj_freed+0x20b/0x250
[ 1136.321429]  [<ffffffff8112e7f2>] ? kmem_cache_destroy+0x92/0x100
[ 1136.321433]  [<ffffffff8115d945>] kmem_cache_free+0x125/0x210
[ 1136.321436]  [<ffffffff8112e7f2>] kmem_cache_destroy+0x92/0x100
[ 1136.321443]  [<ffffffffa046b806>] nf_conntrack_cleanup_net_list+0x126/0x160 [nf_conntrack]
[ 1136.321449]  [<ffffffffa046c43d>] nf_conntrack_pernet_exit+0x6d/0x80 [nf_conntrack]
[ 1136.321453]  [<ffffffff81511cc3>] ops_exit_list.isra.3+0x53/0x60
[ 1136.321457]  [<ffffffff815124f0>] cleanup_net+0x100/0x1b0
[ 1136.321460]  [<ffffffff8106b31e>] process_one_work+0x18e/0x430
[ 1136.321463]  [<ffffffff8106bf49>] worker_thread+0x119/0x390
[ 1136.321467]  [<ffffffff8106be30>] ? manage_workers.isra.23+0x2a0/0x2a0
[ 1136.321470]  [<ffffffff8107210b>] kthread+0xbb/0xc0
[ 1136.321472]  [<ffffffff81072050>] ? kthread_create_on_node+0x110/0x110
[ 1136.321477]  [<ffffffff8161b8fc>] ret_from_fork+0x7c/0xb0
[ 1136.321479]  [<ffffffff81072050>] ? kthread_create_on_node+0x110/0x110
[ 1136.321481] ---[ end trace 25f53c192da70825 ]---

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-11-18 14:07:19 +01:00
Holger Eitzenberger f7b13e4330 netfilter: introduce nf_conn_acct structure
Encapsulate counters for both directions into nf_conn_acct. During
that process also consistently name pointers to the extend 'acct',
not 'counters'. This patch is a cleanup.

Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-11-03 21:48:49 +01:00
Patrick McHardy 48b1de4c11 netfilter: add SYNPROXY core/target
Add a SYNPROXY for netfilter. The code is split into two parts, the synproxy
core with common functions and an address family specific target.

The SYNPROXY receives the connection request from the client, responds with
a SYN/ACK containing a SYN cookie and announcing a zero window and checks
whether the final ACK from the client contains a valid cookie.

It then establishes a connection to the original destination and, if
successful, sends a window update to the client with the window size
announced by the server.

Support for timestamps, SACK, window scaling and MSS options can be
statically configured as target parameters if the features of the server
are known. If timestamps are used, the timestamp value sent back to
the client in the SYN/ACK will be different from the real timestamp of
the server. In order to now break PAWS, the timestamps are translated in
the direction server->client.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Tested-by: Martin Topholm <mph@one.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-08-28 00:27:54 +02:00
Patrick McHardy 41d73ec053 netfilter: nf_conntrack: make sequence number adjustments usuable without NAT
Split out sequence number adjustments from NAT and move them to the conntrack
core to make them usable for SYN proxying. The sequence number adjustment
information is moved to a seperate extend. The extend is added to new
conntracks when a NAT mapping is set up for a connection using a helper.

As a side effect, this saves 24 bytes per connection with NAT in the common
case that a connection does not have a helper assigned.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Tested-by: Martin Topholm <mph@one.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-08-28 00:26:48 +02:00
Florian Westphal c655bc6896 netfilter: nf_conntrack: don't send destroy events from iterator
Let nf_ct_delete handle delivery of the DESTROY event.

Based on earlier patch from Pablo Neira.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-08-09 12:03:33 +02:00
Patrick McHardy 2d89c68ac7 netfilter: nf_nat: change sequence number adjustments to 32 bits
Using 16 bits is too small, when many adjustments happen the offsets might
overflow and break the connection.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-07-31 19:54:51 +02:00
Florian Westphal 02982c27ba netfilter: nf_conntrack: remove duplicate code in ctnetlink
ctnetlink contains copy-paste code from death_by_timeout.  In order to
avoid changing both places in upcoming event delivery patch,
export death_by_timeout functionality and use it in the ctnetlink code.

Based on earlier patch from Pablo Neira.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-07-31 18:51:23 +02:00
Patrick McHardy 312a0c16c1 netfilter: nf_conntrack: constify sk_buff argument to nf_ct_attach()
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-07-31 16:37:38 +02:00
Linus Torvalds 73287a43cc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Highlights (1721 non-merge commits, this has to be a record of some
  sort):

   1) Add 'random' mode to team driver, from Jiri Pirko and Eric
      Dumazet.

   2) Make it so that any driver that supports configuration of multiple
      MAC addresses can provide the forwarding database add and del
      calls by providing a default implementation and hooking that up if
      the driver doesn't have an explicit set of handlers.  From Vlad
      Yasevich.

   3) Support GSO segmentation over tunnels and other encapsulating
      devices such as VXLAN, from Pravin B Shelar.

   4) Support L2 GRE tunnels in the flow dissector, from Michael Dalton.

   5) Implement Tail Loss Probe (TLP) detection in TCP, from Nandita
      Dukkipati.

   6) In the PHY layer, allow supporting wake-on-lan in situations where
      the PHY registers have to be written for it to be configured.

      Use it to support wake-on-lan in mv643xx_eth.

      From Michael Stapelberg.

   7) Significantly improve firewire IPV6 support, from YOSHIFUJI
      Hideaki.

   8) Allow multiple packets to be sent in a single transmission using
      network coding in batman-adv, from Martin Hundebøll.

   9) Add support for T5 cxgb4 chips, from Santosh Rastapur.

  10) Generalize the VXLAN forwarding tables so that there is more
      flexibility in configurating various aspects of the endpoints.
      From David Stevens.

  11) Support RSS and TSO in hardware over GRE tunnels in bxn2x driver,
      from Dmitry Kravkov.

  12) Zero copy support in nfnelink_queue, from Eric Dumazet and Pablo
      Neira Ayuso.

  13) Start adding networking selftests.

  14) In situations of overload on the same AF_PACKET fanout socket, or
      per-cpu packet receive queue, minimize drop by distributing the
      load to other cpus/fanouts.  From Willem de Bruijn and Eric
      Dumazet.

  15) Add support for new payload offset BPF instruction, from Daniel
      Borkmann.

  16) Convert several drivers over to mdoule_platform_driver(), from
      Sachin Kamat.

  17) Provide a minimal BPF JIT image disassembler userspace tool, from
      Daniel Borkmann.

  18) Rewrite F-RTO implementation in TCP to match the final
      specification of it in RFC4138 and RFC5682.  From Yuchung Cheng.

  19) Provide netlink socket diag of netlink sockets ("Yo dawg, I hear
      you like netlink, so I implemented netlink dumping of netlink
      sockets.") From Andrey Vagin.

  20) Remove ugly passing of rtnetlink attributes into rtnl_doit
      functions, from Thomas Graf.

  21) Allow userspace to be able to see if a configuration change occurs
      in the middle of an address or device list dump, from Nicolas
      Dichtel.

  22) Support RFC3168 ECN protection for ipv6 fragments, from Hannes
      Frederic Sowa.

  23) Increase accuracy of packet length used by packet scheduler, from
      Jason Wang.

  24) Beginning set of changes to make ipv4/ipv6 fragment handling more
      scalable and less susceptible to overload and locking contention,
      from Jesper Dangaard Brouer.

  25) Get rid of using non-type-safe NLMSG_* macros and use nlmsg_*()
      instead.  From Hong Zhiguo.

  26) Optimize route usage in IPVS by avoiding reference counting where
      possible, from Julian Anastasov.

  27) Convert IPVS schedulers to RCU, also from Julian Anastasov.

  28) Support cpu fanouts in xt_NFQUEUE netfilter target, from Holger
      Eitzenberger.

  29) Network namespace support for nf_log, ebt_log, xt_LOG, ipt_ULOG,
      nfnetlink_log, and nfnetlink_queue.  From Gao feng.

  30) Implement RFC3168 ECN protection, from Hannes Frederic Sowa.

  31) Support several new r8169 chips, from Hayes Wang.

  32) Support tokenized interface identifiers in ipv6, from Daniel
      Borkmann.

  33) Use usbnet_link_change() helper in USB net driver, from Ming Lei.

  34) Add 802.1ad vlan offload support, from Patrick McHardy.

  35) Support mmap() based netlink communication, also from Patrick
      McHardy.

  36) Support HW timestamping in mlx4 driver, from Amir Vadai.

  37) Rationalize AF_PACKET packet timestamping when transmitting, from
      Willem de Bruijn and Daniel Borkmann.

  38) Bring parity to what's provided by /proc/net/packet socket dumping
      and the info provided by netlink socket dumping of AF_PACKET
      sockets.  From Nicolas Dichtel.

  39) Fix peeking beyond zero sized SKBs in AF_UNIX, from Benjamin
      Poirier"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1722 commits)
  filter: fix va_list build error
  af_unix: fix a fatal race with bit fields
  bnx2x: Prevent memory leak when cnic is absent
  bnx2x: correct reading of speed capabilities
  net: sctp: attribute printl with __printf for gcc fmt checks
  netlink: kconfig: move mmap i/o into netlink kconfig
  netpoll: convert mutex into a semaphore
  netlink: Fix skb ref counting.
  net_sched: act_ipt forward compat with xtables
  mlx4_en: fix a build error on 32bit arches
  Revert "bnx2x: allow nvram test to run when device is down"
  bridge: avoid OOPS if root port not found
  drivers: net: cpsw: fix kernel warn on cpsw irq enable
  sh_eth: use random MAC address if no valid one supplied
  3c509.c: call SET_NETDEV_DEV for all device types (ISA/ISAPnP/EISA)
  tg3: fix to append hardware time stamping flags
  unix/stream: fix peeking with an offset larger than data in queue
  unix/dgram: fix peeking with an offset larger than data in queue
  unix/dgram: peek beyond 0-sized skbs
  openvswitch: Remove unneeded ovs_netdev_get_ifindex()
  ...
2013-05-01 14:08:52 -07:00
Akinobu Mita ca3d41a588 net/netfilter: rename random32() to prandom_u32()
Use preferable function name which implies using a pseudo-random
number generator.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-29 18:28:43 -07:00
David S. Miller 95a06161e6 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
The following patchset contains a small batch of Netfilter
updates for your net-next tree, they are:

* Three patches that provide more accurate error reporting to
  user-space, instead of -EPERM, in IPv4/IPv6 netfilter re-routing
  code and NAT, from Patrick McHardy.

* Update copyright statements in Netfilter filters of
  Patrick McHardy, from himself.

* Add Kconfig dependency on the raw/mangle tables to the
  rpfilter, from Florian Westphal.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-19 17:55:29 -04:00
Patrick McHardy ec464e5dc5 netfilter: rename netlink related "pid" variables to "portid"
Get rid of the confusing mix of pid and portid and use portid consistently
for all netlink related socket identities.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-04-19 14:58:36 -04:00
Patrick McHardy f229f6ce48 netfilter: add my copyright statements
Add copyright statements to all netfilter files which have had significant
changes done by myself in the past.

Some notes:

- nf_conntrack_ecache.c was incorrectly attributed to Rusty and Netfilter
  Core Team when it got split out of nf_conntrack_core.c. The copyrights
  even state a date which lies six years before it was written. It was
  written in 2005 by Harald and myself.

- net/ipv{4,6}/netfilter.c, net/netfitler/nf_queue.c were missing copyright
  statements. I've added the copyright statement from net/netfilter/core.c,
  where this code originated

- for nf_conntrack_proto_tcp.c I've also added Jozsef, since I didn't want
  it to give the wrong impression

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-04-18 20:27:55 +02:00
Vladimir Davydov dece40e848 netfilter: nf_conntrack: speed up module removal path if netns in use
The patch introduces nf_conntrack_cleanup_net_list(), which cleanups
nf_conntrack for a list of netns and calls synchronize_net() only once
for them all. This should reduce netns destruction time.

I've measured cleanup time for 1k dummy net ns. Here are the results:

 <without the patch>
 # modprobe nf_conntrack
 # time modprobe -r nf_conntrack

 real	0m10.337s
 user	0m0.000s
 sys	0m0.376s

 <with the patch>
 # modprobe nf_conntrack
 # time modprobe -r nf_conntrack

 real    0m5.661s
 user    0m0.000s
 sys     0m0.216s

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-03-19 17:08:31 +01:00
stephen hemminger 493763684f netfilter: nf_conntrack: add include to fix sparse warning
Include header file to pickup prototype of nf_nat_seq_adjust_hook

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-03-19 17:05:53 +01:00
Gao feng 04d8700179 netfilter: nf_ct_proto: move initialization out of pernet_operations
Move the global initial codes to the module_init/exit context.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-23 12:56:33 +01:00
Gao feng 5f69b8f521 netfilter: nf_ct_labels: move initialization out of pernet_operations
Move the global initial codes to the module_init/exit context.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-23 12:56:23 +01:00
Gao feng 5e615b2200 netfilter: nf_ct_helper: move initialization out of pernet_operations
Move the global initial codes to the module_init/exit context.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-23 12:56:13 +01:00
Gao feng 8684094cf1 netfilter: nf_ct_timeout: move initialization out of pernet_operations
Move the global initial codes to the module_init/exit context.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-23 12:56:02 +01:00
Gao feng 3fe0f943d4 netfilter: nf_ct_ecache: move initialization out of pernet_operations
Move the global initial codes to the module_init/exit context.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-23 12:55:50 +01:00
Gao feng 73f4001a52 netfilter: nf_ct_tstamp: move initialization out of pernet_operations
Move the global initial codes to the module_init/exit context.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-23 12:55:39 +01:00
Gao feng b7ff3a1fae netfilter: nf_ct_acct: move initialization out of pernet_operations
Move the global initial codes to the module_init/exit context.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-23 12:55:29 +01:00
Gao feng 83b4dbe198 netfilter: nf_ct_expect: move initialization out of pernet_operations
Move the global initial codes to the module_init/exit context.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-23 12:55:00 +01:00
Gao feng f94161c1bb netfilter: nf_conntrack: move initialization out of pernet operations
nf_conntrack initialization and cleanup codes happens in pernet
operations function. This task should be done in module_init/exit.
We can't use init_net to identify if it's the right time to initialize
or cleanup since we cannot make assumption on the order netns are
created/destroyed.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-23 12:53:35 +01:00
Florian Westphal c539f01717 netfilter: add connlabel conntrack extension
similar to connmarks, except labels are bit-based; i.e.
all labels may be attached to a flow at the same time.

Up to 128 labels are supported.  Supporting more labels
is possible, but requires increasing the ct offset delta
from u8 to u16 type due to increased extension sizes.

Mapping of bit-identifier to label name is done in userspace.

The extension is enabled at run-time once "-m connlabel" netfilter
rules are added.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-18 00:28:15 +01:00
Pablo Neira Ayuso 1e47ee8367 netfilter: nf_conntrack: fix BUG_ON while removing nf_conntrack with netns
canqun zhang reported that we're hitting BUG_ON in the
nf_conntrack_destroy path when calling kfree_skb while
rmmod'ing the nf_conntrack module.

Currently, the nf_ct_destroy hook is being set to NULL in the
destroy path of conntrack.init_net. However, this is a problem
since init_net may be destroyed before any other existing netns
(we cannot assume any specific ordering while releasing existing
netns according to what I read in recent emails).

Thanks to Gao feng for initial patch to address this issue.

Reported-by: canqun zhang <canqunzhang@gmail.com>
Acked-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2013-01-12 14:12:36 +01:00
Pablo Neira Ayuso 252b3e8c1b netfilter: xt_CT: fix crash while destroy ct templates
In (d871bef netfilter: ctnetlink: dump entries from the dying and
unconfirmed lists), we assume that all conntrack objects are
inserted in any of the existing lists. However, template conntrack
objects were not. This results in hitting BUG_ON in the
destroy_conntrack path while removing a rule that uses the CT target.

This patch fixes the situation by adding the template lists, which
is where template conntrack objects reside now.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-12-16 23:44:12 +01:00
Abhijit Pawar a71258d79e net: remove obsolete simple_strto<foo>
This patch removes the redundant occurences of simple_strto<foo>

Signed-off-by: Abhijit Pawar <abhi.c.pawar@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-11 12:49:53 -05:00
Abhijit Pawar 4b5511ebc7 net: remove obsolete simple_strto<foo>
This patch replace the obsolete simple_strto<foo> with kstrto<foo>

Signed-off-by: Abhijit Pawar <abhi.c.pawar@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-12-10 14:09:00 -05:00
Pablo Neira Ayuso 04dac0111d netfilter: nf_conntrack: improve nf_conn object traceability
This patch modifies the conntrack subsystem so that all existing
allocated conntrack objects can be found in any of the following
places:

* the hash table, this is the typical place for alive conntrack objects.
* the unconfirmed list, this is the place for newly created conntrack objects
  that are still traversing the stack.
* the dying list, this is where you can find conntrack objects that are dying
  or that should die anytime soon (eg. once the destroy event is delivered to
  the conntrackd daemon).

Thus, we make sure that we follow the track for all existing conntrack
objects. This patch, together with some extension of the ctnetlink interface
to dump the content of the dying and unconfirmed lists, will help in case
to debug suspected nf_conn object leaks.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-12-03 15:06:33 +01:00
Patrick McHardy b0cdb1d9a9 netfilter: nf_nat: fix oops when unloading protocol modules
When unloading a protocol module nf_ct_iterate_cleanup() is used to
remove all conntracks using the protocol from the bysource hash and
clean their NAT sections. Since the conntrack isn't actually killed,
the NAT callback is invoked twice, once for each direction, which
causes an oops when trying to delete it from the bysource hash for
the second time.

The same oops can also happen when removing both an L3 and L4 protocol
since the cleanup function doesn't check whether the conntrack has
already been cleaned up.

Pid: 4052, comm: modprobe Not tainted 3.6.0-rc3-test-nat-unload-fix+ #32 Red Hat KVM
RIP: 0010:[<ffffffffa002c303>]  [<ffffffffa002c303>] nf_nat_proto_clean+0x73/0xd0 [nf_nat]
RSP: 0018:ffff88007808fe18  EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8800728550c0 RCX: ffff8800756288b0
RDX: dead000000200200 RSI: ffff88007808fe88 RDI: ffffffffa002f208
RBP: ffff88007808fe28 R08: ffff88007808e000 R09: 0000000000000000
R10: dead000000200200 R11: dead000000100100 R12: ffffffff81c6dc00
R13: ffff8800787582b8 R14: ffff880078758278 R15: ffff88007808fe88
FS:  00007f515985d700(0000) GS:ffff88007cd00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 00007f515986a000 CR3: 000000007867a000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process modprobe (pid: 4052, threadinfo ffff88007808e000, task ffff8800756288b0)
Stack:
 ffff88007808fe68 ffffffffa002c290 ffff88007808fe78 ffffffff815614e3
 ffffffff00000000 00000aeb00000246 ffff88007808fe68 ffffffff81c6dc00
 ffff88007808fe88 ffffffffa00358a0 0000000000000000 000000000040f5b0
Call Trace:
 [<ffffffffa002c290>] ? nf_nat_net_exit+0x50/0x50 [nf_nat]
 [<ffffffff815614e3>] nf_ct_iterate_cleanup+0xc3/0x170
 [<ffffffffa002c55a>] nf_nat_l3proto_unregister+0x8a/0x100 [nf_nat]
 [<ffffffff812a0303>] ? compat_prepare_timeout+0x13/0xb0
 [<ffffffffa0035848>] nf_nat_l3proto_ipv4_exit+0x10/0x23 [nf_nat_ipv4]
 ...

To fix this,

- check whether the conntrack has already been cleaned up in
  nf_nat_proto_clean

- change nf_ct_iterate_cleanup() to only invoke the callback function
  once for each conntrack (IP_CT_DIR_ORIGINAL).

The second change doesn't affect other callers since when conntracks are
actually killed, both directions are removed from the hash immediately
and the callback is already only invoked once. If it is not killed, the
second callback invocation will always return the same decision not to
kill it.

Reported-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-09-21 11:35:18 +02:00
Pablo Neira Ayuso ace1fe1231 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
This merges (3f509c6 netfilter: nf_nat_sip: fix incorrect handling
of EBUSY for RTCP expectation) to Patrick McHardy's IPv6 NAT changes.
2012-09-03 15:34:51 +02:00
Pablo Neira Ayuso 84b5ee939e netfilter: nf_conntrack: add nf_ct_timeout_lookup
This patch adds the new nf_ct_timeout_lookup function to encapsulate
the timeout policy attachment that is called in the nf_conntrack_in
path.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-09-03 13:33:03 +02:00
Pablo Neira Ayuso 5b423f6a40 netfilter: nf_conntrack: fix racy timer handling with reliable events
Existing code assumes that del_timer returns true for alive conntrack
entries. However, this is not true if reliable events are enabled.
In that case, del_timer may return true for entries that were
just inserted in the dying list. Note that packets / ctnetlink may
hold references to conntrack entries that were just inserted to such
list.

This patch fixes the issue by adding an independent timer for
event delivery. This increases the size of the ecache extension.
Still we can revisit this later and use variable size extensions
to allocate this area on demand.

Tested-by: Oliver Smith <olipro@8.c.9.b.0.7.4.0.1.0.0.2.ip6.arpa>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-08-31 15:50:28 +02:00
Patrick McHardy c7232c9979 netfilter: add protocol independent NAT core
Convert the IPv4 NAT implementation to a protocol independent core and
address family specific modules.

Signed-off-by: Patrick McHardy <kaber@trash.net>
2012-08-30 03:00:14 +02:00
Pablo Neira Ayuso 1afc56794e netfilter: nf_ct_helper: implement variable length helper private data
This patch uses the new variable length conntrack extensions.

Instead of using union nf_conntrack_help that contain all the
helper private data information, we allocate variable length
area to store the private helper data.

This patch includes the modification of all existing helpers.
It also includes a couple of include header to avoid compilation
warnings.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-16 15:08:55 +02:00
David S. Miller 67da255210 Merge branch 'master' of git://1984.lsi.us.es/net-next 2012-06-11 12:56:14 -07:00
Gao feng 15f585bd76 netfilter: nf_ct_generic: add namespace support
This patch adds namespace support for the generic layer 4 protocol
tracker.

Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-06-07 14:58:39 +02:00
Joe Perches e3192690a3 net: Remove casts to same type
Adding casts of objects to the same type is unnecessary
and confusing for a human reader.

For example, this cast:

	int y;
	int *p = (int *)&y;

I used the coccinelle script below to find and remove these
unnecessary casts.  I manually removed the conversions this
script produces of casts with __force and __user.

@@
type T;
T *p;
@@

-	(T *)p
+	p

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-04 11:45:11 -04:00
Joe Perches e87cc4728f net: Convert net_ratelimit uses to net_<level>_ratelimited
Standardize the net core ratelimited logging functions.

Coalesce formats, align arguments.
Change a printk then vprintk sequence to use printf extension %pV.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-05-15 13:45:03 -04:00
Eric Leblond a900689264 netfilter: nf_ct_helper: allow to disable automatic helper assignment
This patch allows you to disable automatic conntrack helper
lookup based on TCP/UDP ports, eg.

echo 0 > /proc/sys/net/netfilter/nf_conntrack_helper

[ Note: flows that already got a helper will keep using it even
  if automatic helper assignment has been disabled ]

Once this behaviour has been disabled, you have to explicitly
use the iptables CT target to attach helper to flows.

There are good reasons to stop supporting automatic helper
assignment, for further information, please read:

http://www.netfilter.org/news.html#2012-04-03

This patch also adds one message to inform that automatic helper
assignment is deprecated and it will be removed soon (this is
spotted only once, with the first flow that gets a helper attached
to make it as less annoying as possible).

Signed-off-by: Eric Leblond <eric@regit.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2012-05-08 19:35:18 +02:00