Commit Graph

79 Commits

Author SHA1 Message Date
Liping Zhang d91fc59cd7 netfilter: introduce nf_conntrack_helper_put helper function
And convert module_put invocation to nf_conntrack_helper_put, this is
prepared for the followup patch, which will add a refcnt for cthelper,
so we can reject the deleting request when cthelper is in use.

Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-15 12:42:29 +02:00
David S. Miller 4d89ac2dd5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter/IPVS/OVS fixes for net

The following patchset contains a rather large batch of Netfilter, IPVS
and OVS fixes for your net tree. This includes fixes for ctnetlink, the
userspace conntrack helper infrastructure, conntrack OVS support,
ebtables DNAT target, several leaks in error path among other. More
specifically, they are:

1) Fix reference count leak in the CT target error path, from Gao Feng.

2) Remove conntrack entry clashing with a matching expectation, patch
   from Jarno Rajahalme.

3) Fix bogus EEXIST when registering two different userspace helpers,
   from Liping Zhang.

4) Don't leak dummy elements in the new bitmap set type in nf_tables,
   from Liping Zhang.

5) Get rid of module autoload from conntrack update path in ctnetlink,
   we don't need autoload at this late stage and it is happening with
   rcu read lock held which is not good. From Liping Zhang.

6) Fix deadlock due to double-acquire of the expect_lock from conntrack
   update path, this fixes a bug that was introduced when the central
   spinlock got removed. Again from Liping Zhang.

7) Safe ct->status update from ctnetlink path, from Liping. The expect_lock
   protection that was selected when the central spinlock was removed was
   not really protecting anything at all.

8) Protect sequence adjustment under ct->lock.

9) Missing socket match with IPv6, from Peter Tirsek.

10) Adjust skb->pkt_type of DNAT'ed frames from ebtables, from
    Linus Luessing.

11) Don't give up on evaluating the expression on new entries added via
    dynset expression in nf_tables, from Liping Zhang.

12) Use skb_checksum() when mangling icmpv6 in IPv6 NAT as this deals
    with non-linear skbuffs.

13) Don't allow IPv6 service in IPVS if no IPv6 support is available,
    from Paolo Abeni.

14) Missing mutex release in error path of xt_find_table_lock(), from
    Dan Carpenter.

15) Update maintainers files, Netfilter section. Add Florian to the
    file, refer to nftables.org and change project status from Supported
    to Maintained.

16) Bail out on mismatching extensions in element updates in nf_tables.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-03 10:11:26 -04:00
David S. Miller a01aa920b8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter updates for your net-next
tree. A large bunch of code cleanups, simplify the conntrack extension
codebase, get rid of the fake conntrack object, speed up netns by
selective synchronize_net() calls. More specifically, they are:

1) Check for ct->status bit instead of using nfct_nat() from IPVS and
   Netfilter codebase, patch from Florian Westphal.

2) Use kcalloc() wherever possible in the IPVS code, from Varsha Rao.

3) Simplify FTP IPVS helper module registration path, from Arushi Singhal.

4) Introduce nft_is_base_chain() helper function.

5) Enforce expectation limit from userspace conntrack helper,
   from Gao Feng.

6) Add nf_ct_remove_expect() helper function, from Gao Feng.

7) NAT mangle helper function return boolean, from Gao Feng.

8) ctnetlink_alloc_expect() should only work for conntrack with
   helpers, from Gao Feng.

9) Add nfnl_msg_type() helper function to nfnetlink to build the
   netlink message type.

10) Get rid of unnecessary cast on void, from simran singhal.

11) Use seq_puts()/seq_putc() instead of seq_printf() where possible,
    also from simran singhal.

12) Use list_prev_entry() from nf_tables, from simran signhal.

13) Remove unnecessary & on pointer function in the Netfilter and IPVS
    code.

14) Remove obsolete comment on set of rules per CPU in ip6_tables,
    no longer true. From Arushi Singhal.

15) Remove duplicated nf_conntrack_l4proto_udplite4, from Gao Feng.

16) Remove unnecessary nested rcu_read_lock() in
    __nf_nat_decode_session(). Code running from hooks are already
    guaranteed to run under RCU read side.

17) Remove deadcode in nf_tables_getobj(), from Aaron Conole.

18) Remove double assignment in nf_ct_l4proto_pernet_unregister_one(),
    also from Aaron.

19) Get rid of unsed __ip_set_get_netlink(), from Aaron Conole.

20) Don't propagate NF_DROP error to userspace via ctnetlink in
    __nf_nat_alloc_null_binding() function, from Gao Feng.

21) Revisit nf_ct_deliver_cached_events() to remove unnecessary checks,
    from Gao Feng.

22) Kill the fake untracked conntrack objects, use ctinfo instead to
    annotate a conntrack object is untracked, from Florian Westphal.

23) Remove nf_ct_is_untracked(), now obsolete since we have no
    conntrack template anymore, from Florian.

24) Add event mask support to nft_ct, also from Florian.

25) Move nf_conn_help structure to
    include/net/netfilter/nf_conntrack_helper.h.

26) Add a fixed 32 bytes scratchpad area for conntrack helpers.
    Thus, we don't deal with variable conntrack extensions anymore.
    Make sure userspace conntrack helper doesn't go over that size.
    Remove variable size ct extension infrastructure now this code
    got no more clients. From Florian Westphal.

27) Restore offset and length of nf_ct_ext structure to 8 bytes now
    that wraparound is not possible any longer, also from Florian.

28) Allow to get rid of unassured flows under stress in conntrack,
    this applies to DCCP, SCTP and TCP protocols, from Florian.

29) Shrink size of nf_conntrack_ecache structure, from Florian.

30) Use TCP_MAX_WSCALE instead of hardcoded 14 in TCP tracker,
    from Gao Feng.

31) Register SYNPROXY hooks on demand, from Florian Westphal.

32) Use pernet hook whenever possible, instead of global hook
    registration, from Florian Westphal.

33) Pass hook structure to ebt_register_table() to consolidate some
    infrastructure code, from Florian Westphal.

34) Use consume_skb() and return NF_STOLEN, instead of NF_DROP in the
    SYNPROXY code, to make sure device stats are not fooled, patch
    from Gao Feng.

35) Remove NF_CT_EXT_F_PREALLOC this kills quite some code that we
    don't need anymore if we just select a fixed size instead of
    expensive runtime time calculation of this. From Florian.

36) Constify nf_ct_extend_register() and nf_ct_extend_unregister(),
    from Florian.

37) Simplify nf_ct_ext_add(), this kills nf_ct_ext_create(), from
    Florian.

38) Attach NAT extension on-demand from masquerade and pptp helper
    path, from Florian.

39) Get rid of useless ip_vs_set_state_timeout(), from Aaron Conole.

40) Speed up netns by selective calls of synchronize_net(), from
    Florian Westphal.

41) Silence stack size warning gcc in 32-bit arch in snmp helper,
    from Florian.

42) Inconditionally call nf_ct_ext_destroy(), even if we have no
    extensions, to deal with the NF_NAT_MANIP_SRC case. Patch from
    Liping Zhang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-05-01 10:47:53 -04:00
Jarno Rajahalme cf5d709188 openvswitch: Delete conntrack entry clashing with an expectation.
Conntrack helpers do not check for a potentially clashing conntrack
entry when creating a new expectation.  Also, nf_conntrack_in() will
check expectations (via init_conntrack()) only if a conntrack entry
can not be found.  The expectation for a packet which also matches an
existing conntrack entry will not be removed by conntrack, and is
currently handled inconsistently by OVS, as OVS expects the
expectation to be removed when the connection tracking entry matching
that expectation is confirmed.

It should be noted that normally an IP stack would not allow reuse of
a 5-tuple of an old (possibly lingering) connection for a new data
connection, so this is somewhat unlikely corner case.  However, it is
possible that a misbehaving source could cause conntrack entries be
created that could then interfere with new related connections.

Fix this in the OVS module by deleting the clashing conntrack entry
after an expectation has been matched.  This causes the following
nf_conntrack_in() call also find the expectation and remove it when
creating the new conntrack entry, as well as the forthcoming reply
direction packets to match the new related connection instead of the
old clashing conntrack entry.

Fixes: 7f8a436eaa ("openvswitch: Add conntrack action")
Reported-by: Yang Song <yangsong@vmware.com>
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-24 20:04:41 +02:00
Jarno Rajahalme 120645513f openvswitch: Add eventmask support to CT action.
Add a new optional conntrack action attribute OVS_CT_ATTR_EVENTMASK,
which can be used in conjunction with the commit flag
(OVS_CT_ATTR_COMMIT) to set the mask of bits specifying which
conntrack events (IPCT_*) should be delivered via the Netfilter
netlink multicast groups.  Default behavior depends on the system
configuration, but typically a lot of events are delivered.  This can be
very chatty for the NFNLGRP_CONNTRACK_UPDATE group, even if only some
types of events are of interest.

Netfilter core init_conntrack() adds the event cache extension, so we
only need to set the ctmask value.  However, if the system is
configured without support for events, the setting will be skipped due
to extension not being found.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Reviewed-by: Greg Rose <gvrose8192@gmail.com>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-24 13:53:25 -04:00
Jarno Rajahalme abd0a4f2b4 openvswitch: Typo fix.
Fix typo in a comment.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Greg Rose <gvrose8192@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-24 13:53:24 -04:00
Florian Westphal ab8bc7ed86 netfilter: remove nf_ct_is_untracked
This function is now obsolete and always returns false.
This change has no effect on generated code.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-04-15 11:51:33 +02:00
Jarno Rajahalme b768b16de5 openvswitch: Fix refcount leak on force commit.
The reference count held for skb needs to be released when the skb's
nfct pointer is cleared regardless of if nf_ct_delete() is called or
not.

Failing to release the skb's reference cound led to deferred conntrack
cleanup spinning forever within nf_conntrack_cleanup_net_list() when
cleaning up a network namespace:

   kworker/u16:0-19025 [004] 45981067.173642: sched_switch: kworker/u16:0:19025 [120] R ==> rcu_preempt:7 [120]
   kworker/u16:0-19025 [004] 45981067.173651: kernel_stack: <stack trace>
=> ___preempt_schedule (ffffffffa001ed36)
=> _raw_spin_unlock_bh (ffffffffa0713290)
=> nf_ct_iterate_cleanup (ffffffffc00a4454)
=> nf_conntrack_cleanup_net_list (ffffffffc00a5e1e)
=> nf_conntrack_pernet_exit (ffffffffc00a63dd)
=> ops_exit_list.isra.1 (ffffffffa06075f3)
=> cleanup_net (ffffffffa0607df0)
=> process_one_work (ffffffffa0084c31)
=> worker_thread (ffffffffa008592b)
=> kthread (ffffffffa008bee2)
=> ret_from_fork (ffffffffa071b67c)

Fixes: dd41d33f0b ("openvswitch: Add force commit.")
Reported-by: Yang Song <yangsong@vmware.com>
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-28 21:56:11 -07:00
Eric Dumazet 48cac18ecf ipv6: orphan skbs in reassembly unit
Andrey reported a use-after-free in IPv6 stack.

Issue here is that we free the socket while it still has skb
in TX path and in some queues.

It happens here because IPv6 reassembly unit messes skb->truesize,
breaking skb_set_owner_w() badly.

We fixed a similar issue for IPV4 in commit 8282f27449 ("inet: frag:
Always orphan skbs inside ip_defrag()")
Acked-by: Joe Stringer <joe@ovn.org>

==================================================================
BUG: KASAN: use-after-free in sock_wfree+0x118/0x120
Read of size 8 at addr ffff880062da0060 by task a.out/4140

page:ffffea00018b6800 count:1 mapcount:0 mapping:          (null)
index:0x0 compound_mapcount: 0
flags: 0x100000000008100(slab|head)
raw: 0100000000008100 0000000000000000 0000000000000000 0000000180130013
raw: dead000000000100 dead000000000200 ffff88006741f140 0000000000000000
page dumped because: kasan: bad access detected

CPU: 0 PID: 4140 Comm: a.out Not tainted 4.10.0-rc3+ #59
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:15
 dump_stack+0x292/0x398 lib/dump_stack.c:51
 describe_address mm/kasan/report.c:262
 kasan_report_error+0x121/0x560 mm/kasan/report.c:370
 kasan_report mm/kasan/report.c:392
 __asan_report_load8_noabort+0x3e/0x40 mm/kasan/report.c:413
 sock_flag ./arch/x86/include/asm/bitops.h:324
 sock_wfree+0x118/0x120 net/core/sock.c:1631
 skb_release_head_state+0xfc/0x250 net/core/skbuff.c:655
 skb_release_all+0x15/0x60 net/core/skbuff.c:668
 __kfree_skb+0x15/0x20 net/core/skbuff.c:684
 kfree_skb+0x16e/0x4e0 net/core/skbuff.c:705
 inet_frag_destroy+0x121/0x290 net/ipv4/inet_fragment.c:304
 inet_frag_put ./include/net/inet_frag.h:133
 nf_ct_frag6_gather+0x1125/0x38b0 net/ipv6/netfilter/nf_conntrack_reasm.c:617
 ipv6_defrag+0x21b/0x350 net/ipv6/netfilter/nf_defrag_ipv6_hooks.c:68
 nf_hook_entry_hookfn ./include/linux/netfilter.h:102
 nf_hook_slow+0xc3/0x290 net/netfilter/core.c:310
 nf_hook ./include/linux/netfilter.h:212
 __ip6_local_out+0x52c/0xaf0 net/ipv6/output_core.c:160
 ip6_local_out+0x2d/0x170 net/ipv6/output_core.c:170
 ip6_send_skb+0xa1/0x340 net/ipv6/ip6_output.c:1722
 ip6_push_pending_frames+0xb3/0xe0 net/ipv6/ip6_output.c:1742
 rawv6_push_pending_frames net/ipv6/raw.c:613
 rawv6_sendmsg+0x2cff/0x4130 net/ipv6/raw.c:927
 inet_sendmsg+0x164/0x5b0 net/ipv4/af_inet.c:744
 sock_sendmsg_nosec net/socket.c:635
 sock_sendmsg+0xca/0x110 net/socket.c:645
 sock_write_iter+0x326/0x620 net/socket.c:848
 new_sync_write fs/read_write.c:499
 __vfs_write+0x483/0x760 fs/read_write.c:512
 vfs_write+0x187/0x530 fs/read_write.c:560
 SYSC_write fs/read_write.c:607
 SyS_write+0xfb/0x230 fs/read_write.c:599
 entry_SYSCALL_64_fastpath+0x1f/0xc2 arch/x86/entry/entry_64.S:203
RIP: 0033:0x7ff26e6f5b79
RSP: 002b:00007ff268e0ed98 EFLAGS: 00000206 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007ff268e0f9c0 RCX: 00007ff26e6f5b79
RDX: 0000000000000010 RSI: 0000000020f50fe1 RDI: 0000000000000003
RBP: 00007ff26ebc1220 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007ff268e0f9c0 R14: 00007ff26efec040 R15: 0000000000000003

The buggy address belongs to the object at ffff880062da0000
 which belongs to the cache RAWv6 of size 1504
The buggy address ffff880062da0060 is located 96 bytes inside
 of 1504-byte region [ffff880062da0000, ffff880062da05e0)

Freed by task 4113:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57
 save_stack+0x43/0xd0 mm/kasan/kasan.c:502
 set_track mm/kasan/kasan.c:514
 kasan_slab_free+0x73/0xc0 mm/kasan/kasan.c:578
 slab_free_hook mm/slub.c:1352
 slab_free_freelist_hook mm/slub.c:1374
 slab_free mm/slub.c:2951
 kmem_cache_free+0xb2/0x2c0 mm/slub.c:2973
 sk_prot_free net/core/sock.c:1377
 __sk_destruct+0x49c/0x6e0 net/core/sock.c:1452
 sk_destruct+0x47/0x80 net/core/sock.c:1460
 __sk_free+0x57/0x230 net/core/sock.c:1468
 sk_free+0x23/0x30 net/core/sock.c:1479
 sock_put ./include/net/sock.h:1638
 sk_common_release+0x31e/0x4e0 net/core/sock.c:2782
 rawv6_close+0x54/0x80 net/ipv6/raw.c:1214
 inet_release+0xed/0x1c0 net/ipv4/af_inet.c:425
 inet6_release+0x50/0x70 net/ipv6/af_inet6.c:431
 sock_release+0x8d/0x1e0 net/socket.c:599
 sock_close+0x16/0x20 net/socket.c:1063
 __fput+0x332/0x7f0 fs/file_table.c:208
 ____fput+0x15/0x20 fs/file_table.c:244
 task_work_run+0x19b/0x270 kernel/task_work.c:116
 exit_task_work ./include/linux/task_work.h:21
 do_exit+0x186b/0x2800 kernel/exit.c:839
 do_group_exit+0x149/0x420 kernel/exit.c:943
 SYSC_exit_group kernel/exit.c:954
 SyS_exit_group+0x1d/0x20 kernel/exit.c:952
 entry_SYSCALL_64_fastpath+0x1f/0xc2 arch/x86/entry/entry_64.S:203

Allocated by task 4115:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:57
 save_stack+0x43/0xd0 mm/kasan/kasan.c:502
 set_track mm/kasan/kasan.c:514
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:605
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:544
 slab_post_alloc_hook mm/slab.h:432
 slab_alloc_node mm/slub.c:2708
 slab_alloc mm/slub.c:2716
 kmem_cache_alloc+0x1af/0x250 mm/slub.c:2721
 sk_prot_alloc+0x65/0x2a0 net/core/sock.c:1334
 sk_alloc+0x105/0x1010 net/core/sock.c:1396
 inet6_create+0x44d/0x1150 net/ipv6/af_inet6.c:183
 __sock_create+0x4f6/0x880 net/socket.c:1199
 sock_create net/socket.c:1239
 SYSC_socket net/socket.c:1269
 SyS_socket+0xf9/0x230 net/socket.c:1249
 entry_SYSCALL_64_fastpath+0x1f/0xc2 arch/x86/entry/entry_64.S:203

Memory state around the buggy address:
 ffff880062d9ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff880062d9ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff880062da0000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff880062da0080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff880062da0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-01 20:55:57 -08:00
Jarno Rajahalme 2317c6b51e openvswitch: Set event bit after initializing labels.
Connlabels are included in conntrack netlink event messages only if
the IPCT_LABEL bit is set in the event cache (see
ctnetlink_conntrack_event()).  Set it after initializing labels for a
new connection.

Found upon further system testing, where it was noticed that labels
were missing from the conntrack events.

Fixes: 193e309678 ("openvswitch: Do not trigger events for unconfirmed connections.")
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-20 10:18:43 -05:00
Jarno Rajahalme 316d4d78cf openvswitch: Pack struct sw_flow_key.
struct sw_flow_key has two 16-bit holes. Move the most matched
conntrack match fields there.  In some typical cases this reduces the
size of the key that needs to be hashed into half and into one cache
line.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09 22:59:34 -05:00
Jarno Rajahalme dd41d33f0b openvswitch: Add force commit.
Stateful network admission policy may allow connections to one
direction and reject connections initiated in the other direction.
After policy change it is possible that for a new connection an
overlapping conntrack entry already exists, where the original
direction of the existing connection is opposed to the new
connection's initial packet.

Most importantly, conntrack state relating to the current packet gets
the "reply" designation based on whether the original direction tuple
or the reply direction tuple matched.  If this "directionality" is
wrong w.r.t. to the stateful network admission policy it may happen
that packets in neither direction are correctly admitted.

This patch adds a new "force commit" option to the OVS conntrack
action that checks the original direction of an existing conntrack
entry.  If that direction is opposed to the current packet, the
existing conntrack entry is deleted and a new one is subsequently
created in the correct direction.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09 22:59:34 -05:00
Jarno Rajahalme 9dd7f8907c openvswitch: Add original direction conntrack tuple to sw_flow_key.
Add the fields of the conntrack original direction 5-tuple to struct
sw_flow_key.  The new fields are initially marked as non-existent, and
are populated whenever a conntrack action is executed and either finds
or generates a conntrack entry.  This means that these fields exist
for all packets that were not rejected by conntrack as untrackable.

The original tuple fields in the sw_flow_key are filled from the
original direction tuple of the conntrack entry relating to the
current packet, or from the original direction tuple of the master
conntrack entry, if the current conntrack entry has a master.
Generally, expected connections of connections having an assigned
helper (e.g., FTP), have a master conntrack entry.

The main purpose of the new conntrack original tuple fields is to
allow matching on them for policy decision purposes, with the premise
that the admissibility of tracked connections reply packets (as well
as original direction packets), and both direction packets of any
related connections may be based on ACL rules applying to the master
connection's original direction 5-tuple.  This also makes it easier to
make policy decisions when the actual packet headers might have been
transformed by NAT, as the original direction 5-tuple represents the
packet headers before any such transformation.

When using the original direction 5-tuple the admissibility of return
and/or related packets need not be based on the mere existence of a
conntrack entry, allowing separation of admission policy from the
established conntrack state.  While existence of a conntrack entry is
required for admission of the return or related packets, policy
changes can render connections that were initially admitted to be
rejected or dropped afterwards.  If the admission of the return and
related packets was based on mere conntrack state (e.g., connection
being in an established state), a policy change that would make the
connection rejected or dropped would need to find and delete all
conntrack entries affected by such a change.  When using the original
direction 5-tuple matching the affected conntrack entries can be
allowed to time out instead, as the established state of the
connection would not need to be the basis for packet admission any
more.

It should be noted that the directionality of related connections may
be the same or different than that of the master connection, and
neither the original direction 5-tuple nor the conntrack state bits
carry this information.  If needed, the directionality of the master
connection can be stored in master's conntrack mark or labels, which
are automatically inherited by the expected related connections.

The fact that neither ARP nor ND packets are trackable by conntrack
allows mutual exclusion between ARP/ND and the new conntrack original
tuple fields.  Hence, the IP addresses are overlaid in union with ARP
and ND fields.  This allows the sw_flow_key to not grow much due to
this patch, but it also means that we must be careful to never use the
new key fields with ARP or ND packets.  ARP is easy to distinguish and
keep mutually exclusive based on the ethernet type, but ND being an
ICMPv6 protocol requires a bit more attention.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09 22:59:34 -05:00
Jarno Rajahalme 09aa98ad49 openvswitch: Inherit master's labels.
We avoid calling into nf_conntrack_in() for expected connections, as
that would remove the expectation that we want to stick around until
we are ready to commit the connection.  Instead, we do a lookup in the
expectation table directly.  However, after a successful expectation
lookup we have set the flow key label field from the master
connection, whereas nf_conntrack_in() does not do this.  This leads to
master's labels being inherited after an expectation lookup, but those
labels not being inherited after the corresponding conntrack action
with a commit flag.

This patch resolves the problem by changing the commit code path to
also inherit the master's labels to the expected connection.
Resolving this conflict in favor of inheriting the labels allows more
information be passed from the master connection to related
connections, which would otherwise be much harder if the 32 bits in
the connmark are not enough.  Labels can still be set explicitly, so
this change only affects the default values of the labels in presense
of a master connection.

Fixes: 7f8a436eaa ("openvswitch: Add conntrack action")
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09 22:59:34 -05:00
Jarno Rajahalme 6ffcea7995 openvswitch: Refactor labels initialization.
Refactoring conntrack labels initialization makes changes in later
patches easier to review.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09 22:59:34 -05:00
Jarno Rajahalme b87cec3814 openvswitch: Simplify labels length logic.
Since 23014011ba ("netfilter: conntrack: support a fixed size of 128
distinct labels"), the size of conntrack labels extension has fixed to
128 bits, so we do not need to check for labels sizes shorter than 128
at run-time.  This patch simplifies labels length logic accordingly,
but allows the conntrack labels size to be increased in the future
without breaking the build.  In the event of conntrack labels
increasing in size OVS would still be able to deal with the 128 first
label bits.

Suggested-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09 22:59:34 -05:00
Jarno Rajahalme cb80d58fae openvswitch: Unionize ovs_key_ct_label with a u32 array.
Make the array of labels in struct ovs_key_ct_label an union, adding a
u32 array of the same byte size as the existing u8 array.  It is
faster to loop through the labels 32 bits at the time, which is also
the alignment of netlink attributes.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09 22:59:34 -05:00
Jarno Rajahalme 193e309678 openvswitch: Do not trigger events for unconfirmed connections.
Receiving change events before the 'new' event for the connection has
been received can be confusing.  Avoid triggering change events for
setting conntrack mark or labels before the conntrack entry has been
confirmed.

Fixes: 182e3042e1 ("openvswitch: Allow matching on conntrack mark")
Fixes: c2ac667358 ("openvswitch: Allow matching on conntrack label")
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09 22:59:34 -05:00
Jarno Rajahalme 9ff464db50 openvswitch: Use inverted tuple in ovs_ct_find_existing() if NATted.
The conntrack lookup for existing connections fails to invert the
packet 5-tuple for NATted packets, and therefore fails to find the
existing conntrack entry.  Conntrack only stores 5-tuples for incoming
packets, and there are various situations where a lookup on a packet
that has already been transformed by NAT needs to be made.  Looking up
an existing conntrack entry upon executing packet received from the
userspace is one of them.

This patch fixes ovs_ct_find_existing() to invert the packet 5-tuple
for the conntrack lookup whenever the packet has already been
transformed by conntrack from its input form as evidenced by one of
the NAT flags being set in the conntrack state metadata.

Fixes: 05752523e5 ("openvswitch: Interface with NAT.")
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09 22:59:34 -05:00
Jarno Rajahalme 5e17da634a openvswitch: Fix comments for skb->_nfct
Fix comments referring to skb 'nfct' and 'nfctinfo' fields now that
they are combined into '_nfct'.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-09 22:59:34 -05:00
David S. Miller 52e01b84a2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for your net-next
tree, they are:

1) Stash ctinfo 3-bit field into pointer to nf_conntrack object from
   sk_buff so we only access one single cacheline in the conntrack
   hotpath. Patchset from Florian Westphal.

2) Don't leak pointer to internal structures when exporting x_tables
   ruleset back to userspace, from Willem DeBruijn. This includes new
   helper functions to copy data to userspace such as xt_data_to_user()
   as well as conversions of our ip_tables, ip6_tables and arp_tables
   clients to use it. Not surprinsingly, ebtables requires an ad-hoc
   update. There is also a new field in x_tables extensions to indicate
   the amount of bytes that we copy to userspace.

3) Add nf_log_all_netns sysctl: This new knob allows you to enable
   logging via nf_log infrastructure for all existing netnamespaces.
   Given the effort to provide pernet syslog has been discontinued,
   let's provide a way to restore logging using netfilter kernel logging
   facilities in trusted environments. Patch from Michal Kubecek.

4) Validate SCTP checksum from conntrack helper, from Davide Caratti.

5) Merge UDPlite conntrack and NAT helpers into UDP, this was mostly
   a copy&paste from the original helper, from Florian Westphal.

6) Reset netfilter state when duplicating packets, also from Florian.

7) Remove unnecessary check for broadcast in IPv6 in pkttype match and
   nft_meta, from Liping Zhang.

8) Add missing code to deal with loopback packets from nft_meta when
   used by the netdev family, also from Liping.

9) Several cleanups on nf_tables, one to remove unnecessary check from
   the netlink control plane path to add table, set and stateful objects
   and code consolidation when unregister chain hooks, from Gao Feng.

10) Fix harmless reference counter underflow in IPVS that, however,
    results in problems with the introduction of the new refcount_t
    type, from David Windsor.

11) Enable LIBCRC32C from nf_ct_sctp instead of nf_nat_sctp,
    from Davide Caratti.

12) Missing documentation on nf_tables uapi header, from Liping Zhang.

13) Use rb_entry() helper in xt_connlimit, from Geliang Tang.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-02-03 16:58:20 -05:00
Florian Westphal c74454fadd netfilter: add and use nf_ct_set helper
Add a helper to assign a nf_conn entry and the ctinfo bits to an sk_buff.
This avoids changing code in followup patch that merges skb->nfct and
skb->nfctinfo into skb->_nfct.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-02 14:31:54 +01:00
Florian Westphal cb9c68363e skbuff: add and use skb_nfct helper
Followup patch renames skb->nfct and changes its type so add a helper to
avoid intrusive rename change later.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-02 14:31:53 +01:00
Lance Richardson 75f01a4c9c openvswitch: maintain correct checksum state in conntrack actions
When executing conntrack actions on skbuffs with checksum mode
CHECKSUM_COMPLETE, the checksum must be updated to account for
header pushes and pulls. Otherwise we get "hw csum failure"
logs similar to this (ICMP packet received on geneve tunnel
via ixgbe NIC):

[  405.740065] genev_sys_6081: hw csum failure
[  405.740106] CPU: 3 PID: 0 Comm: swapper/3 Tainted: G          I     4.10.0-rc3+ #1
[  405.740108] Call Trace:
[  405.740110]  <IRQ>
[  405.740113]  dump_stack+0x63/0x87
[  405.740116]  netdev_rx_csum_fault+0x3a/0x40
[  405.740118]  __skb_checksum_complete+0xcf/0xe0
[  405.740120]  nf_ip_checksum+0xc8/0xf0
[  405.740124]  icmp_error+0x1de/0x351 [nf_conntrack_ipv4]
[  405.740132]  nf_conntrack_in+0xe1/0x550 [nf_conntrack]
[  405.740137]  ? find_bucket.isra.2+0x62/0x70 [openvswitch]
[  405.740143]  __ovs_ct_lookup+0x95/0x980 [openvswitch]
[  405.740145]  ? netif_rx_internal+0x44/0x110
[  405.740149]  ovs_ct_execute+0x147/0x4b0 [openvswitch]
[  405.740153]  do_execute_actions+0x22e/0xa70 [openvswitch]
[  405.740157]  ovs_execute_actions+0x40/0x120 [openvswitch]
[  405.740161]  ovs_dp_process_packet+0x84/0x120 [openvswitch]
[  405.740166]  ovs_vport_receive+0x73/0xd0 [openvswitch]
[  405.740168]  ? udp_rcv+0x1a/0x20
[  405.740170]  ? ip_local_deliver_finish+0x93/0x1e0
[  405.740172]  ? ip_local_deliver+0x6f/0xe0
[  405.740174]  ? ip_rcv_finish+0x3a0/0x3a0
[  405.740176]  ? ip_rcv_finish+0xdb/0x3a0
[  405.740177]  ? ip_rcv+0x2a7/0x400
[  405.740180]  ? __netif_receive_skb_core+0x970/0xa00
[  405.740185]  netdev_frame_hook+0xd3/0x160 [openvswitch]
[  405.740187]  __netif_receive_skb_core+0x1dc/0xa00
[  405.740194]  ? ixgbe_clean_rx_irq+0x46d/0xa20 [ixgbe]
[  405.740197]  __netif_receive_skb+0x18/0x60
[  405.740199]  netif_receive_skb_internal+0x40/0xb0
[  405.740201]  napi_gro_receive+0xcd/0x120
[  405.740204]  gro_cell_poll+0x57/0x80 [geneve]
[  405.740206]  net_rx_action+0x260/0x3c0
[  405.740209]  __do_softirq+0xc9/0x28c
[  405.740211]  irq_exit+0xd9/0xf0
[  405.740213]  do_IRQ+0x51/0xd0
[  405.740215]  common_interrupt+0x93/0x93

Fixes: 7f8a436eaa ("openvswitch: Add conntrack action")
Signed-off-by: Lance Richardson <lrichard@redhat.com>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-01-15 22:15:16 -05:00
David S. Miller 2745529ac7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Couple conflicts resolved here:

1) In the MACB driver, a bug fix to properly initialize the
   RX tail pointer properly overlapped with some changes
   to support variable sized rings.

2) In XGBE we had a "CONFIG_PM" --> "CONFIG_PM_SLEEP" fix
   overlapping with a reorganization of the driver to support
   ACPI, OF, as well as PCI variants of the chip.

3) In 'net' we had several probe error path bug fixes to the
   stmmac driver, meanwhile a lot of this code was cleaned up
   and reorganized in 'net-next'.

4) The cls_flower classifier obtained a helper function in
   'net-next' called __fl_delete() and this overlapped with
   Daniel Borkamann's bug fix to use RCU for object destruction
   in 'net'.  It also overlapped with Jiri's change to guard
   the rhashtable_remove_fast() call with a check against
   tc_skip_sw().

5) In mlx4, a revert bug fix in 'net' overlapped with some
   unrelated changes in 'net-next'.

6) In geneve, a stale header pointer after pskb_expand_head()
   bug fix in 'net' overlapped with a large reorganization of
   the same code in 'net-next'.  Since the 'net-next' code no
   longer had the bug in question, there was nothing to do
   other than to simply take the 'net-next' hunks.

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-03 12:29:53 -05:00
Daniele Di Proietto f92a80a997 openvswitch: Fix skb leak in IPv6 reassembly.
If nf_ct_frag6_gather() returns an error other than -EINPROGRESS, it
means that we still have a reference to the skb.  We should free it
before returning from handle_fragments, as stated in the comment above.

Fixes: daaa7d647f ("netfilter: ipv6: avoid nf_iterate recursion")
CC: Florian Westphal <fw@strlen.de>
CC: Pravin B Shelar <pshelar@ovn.org>
CC: Joe Stringer <joe@ovn.org>
Signed-off-by: Daniele Di Proietto <diproiettod@ovn.org>
Acked-by: Pravin B Shelar <pshelar@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-30 11:00:45 -05:00
Pablo Neira Ayuso 08733a0cb7 netfilter: handle NF_REPEAT from nf_conntrack_in()
NF_REPEAT is only needed from nf_conntrack_in() under a very specific
case required by the TCP protocol tracker, we can handle this case
without returning to the core hook path. Handling of NF_REPEAT from the
nf_reinject() is left untouched.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-11-03 11:53:00 +01:00
Joe Stringer 76644232e6 openvswitch: Free tmpl with tmpl_free.
When an error occurs during conntrack template creation as part of
actions validation, we need to free the template. Previously we've been
using nf_ct_put() to do this, but nf_ct_tmpl_free() is more appropriate.

Signed-off-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-04 11:38:10 -07:00
Jarno Rajahalme bce91f8a42 openvswitch: Remove incorrect WARN_ONCE().
ovs_ct_find_existing() issues a warning if an existing conntrack entry
classified as IP_CT_NEW is found, with the premise that this should
not happen.  However, a newly confirmed, non-expected conntrack entry
remains IP_CT_NEW as long as no reply direction traffic is seen.  This
has resulted into somewhat confusing kernel log messages.  This patch
removes this check and warning.

Fixes: 289f2253 ("openvswitch: Find existing conntrack entry after upcall.")
Suggested-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-08-03 11:50:40 -07:00
Florian Westphal 23014011ba netfilter: conntrack: support a fixed size of 128 distinct labels
The conntrack label extension is currently variable-sized, e.g. if
only 2 labels are used by iptables rules then the labels->bits[] array
will only contain one element.

We track size of each label storage area in the 'words' member.

But in nftables and openvswitch we always have to ask for worst-case
since we don't know what bit will be used at configuration time.

As most arches are 64bit we need to allocate 24 bytes in this case:

struct nf_conn_labels {
    u8            words;   /*     0     1 */
    /* XXX 7 bytes hole, try to pack */
    long unsigned bits[2]; /*     8     24 */

Make bits a fixed size and drop the words member, it simplifies
the code and only increases memory requirements on x86 when
less than 64bit labels are required.

We still only allocate the extension if its needed.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-07-22 17:04:55 +02:00
David S. Miller ee58b57100 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Several cases of overlapping changes, except the packet scheduler
conflicts which deal with the addition of the free list parameter
to qdisc_enqueue().

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-30 05:03:36 -04:00
Samuel Gauthier d913d3a763 openvswitch: fix conntrack netlink event delivery
Only the first and last netlink message for a particular conntrack are
actually sent. The first message is sent through nf_conntrack_confirm when
the conntrack is committed. The last one is sent when the conntrack is
destroyed on timeout. The other conntrack state change messages are not
advertised.

When the conntrack subsystem is used from netfilter, nf_conntrack_confirm
is called for each packet, from the postrouting hook, which in turn calls
nf_ct_deliver_cached_events to send the state change netlink messages.

This commit fixes the problem by calling nf_ct_deliver_cached_events in the
non-commit case as well.

Fixes: 7f8a436eaa ("openvswitch: Add conntrack action")
CC: Joe Stringer <joestringer@nicira.com>
CC: Justin Pettit <jpettit@nicira.com>
CC: Andy Zhou <azhou@nicira.com>
CC: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Samuel Gauthier <samuel.gauthier@6wind.com>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-29 08:13:59 -04:00
Jarno Rajahalme 7d904c7bcd openvswitch: Only set mark and labels with a commit flag.
Only set conntrack mark or labels when the commit flag is specified.
This makes sure we can not set them before the connection has been
persisted, as in that case the mark and labels would be lost in an
event of an userspace upcall.

OVS userspace already requires the commit flag to accept setting
ct_mark and/or ct_labels.  Validate for this in the kernel API.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-25 11:55:51 -04:00
Jarno Rajahalme 1c1779fa54 openvswitch: Set mark and labels before confirming.
Set conntrack mark and labels right before committing so that
the initial conntrack NEW event has the mark and labels.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-06-25 11:55:51 -04:00
David S. Miller 909b27f706 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/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>
2016-05-15 13:32:48 -04:00
Joe Stringer 16ec3d4fbb openvswitch: Fix cached ct with helper.
When using conntrack helpers from OVS, a common configuration is to
perform a lookup without specifying a helper, then go through a
firewalling policy, only to decide to attach a helper afterwards.

In this case, the initial lookup will cause a ct entry to be attached to
the skb, then the later commit with helper should attach the helper and
confirm the connection. However, the helper attachment has been missing.
If the user has enabled automatic helper attachment, then this issue
will be masked as it will be applied in init_conntrack(). It is also
masked if the action is executed from ovs_packet_cmd_execute() as that
will construct a fresh skb.

This patch fixes the issue by making an explicit call to try to assign
the helper if there is a discrepancy between the action's helper and the
current skb->nfct.

Fixes: cae3a26275 ("openvswitch: Allow attaching helpers to ct action")
Signed-off-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-05-11 15:14:56 -04:00
Pablo Neira Ayuso 3b78155b1b openvswitch: __nf_ct_l{3,4}proto_find() always return a valid pointer
If the protocol is not natively supported, this assigns generic protocol
tracker so we can always assume a valid pointer after these calls.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Jarno Rajahalme <jrajahalme@nicira.com>
Acked-by: Joe Stringer <joe@ovn.org>
2016-05-05 16:39:50 +02:00
David S. Miller 11afbff861 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for your net-next
tree, mostly from Florian Westphal to sort out the lack of sufficient
validation in x_tables and connlabel preparation patches to add
nf_tables support. They are:

1) Ensure we don't go over the ruleset blob boundaries in
   mark_source_chains().

2) Validate that target jumps land on an existing xt_entry. This extra
   sanitization comes with a performance penalty when loading the ruleset.

3) Introduce xt_check_entry_offsets() and use it from {arp,ip,ip6}tables.

4) Get rid of the smallish check_entry() functions in {arp,ip,ip6}tables.

5) Make sure the minimal possible target size in x_tables.

6) Similar to #3, add xt_compat_check_entry_offsets() for compat code.

7) Check that standard target size is valid.

8) More sanitization to ensure that the target_offset field is correct.

9) Add xt_check_entry_match() to validate that matches are well-formed.

10-12) Three patch to reduce the number of parameters in
    translate_compat_table() for {arp,ip,ip6}tables by using a container
    structure.

13) No need to return value from xt_compat_match_from_user(), so make
    it void.

14) Consolidate translate_table() so it can be used by compat code too.

15) Remove obsolete check for compat code, so we keep consistent with
    what was already removed in the native layout code (back in 2007).

16) Get rid of target jump validation from mark_source_chains(),
    obsoleted by #2.

17) Introduce xt_copy_counters_from_user() to consolidate counter
    copying, and use it from {arp,ip,ip6}tables.

18,22) Get rid of unnecessary explicit inlining in ctnetlink for dump
    functions.

19) Move nf_connlabel_match() to xt_connlabel.

20) Skip event notification if connlabel did not change.

21) Update of nf_connlabels_get() to make the upcoming nft connlabel
    support easier.

23) Remove spinlock to read protocol state field in conntrack.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-24 00:12:08 -04:00
Joe Stringer 49e261a8a2 openvswitch: Orphan skbs before IPv6 defrag
This is the IPv6 counterpart to commit 8282f27449 ("inet: frag: Always
orphan skbs inside ip_defrag()").

Prior to commit 029f7f3b87 ("netfilter: ipv6: nf_defrag: avoid/free
clone operations"), ipv6 fragments sent to nf_ct_frag6_gather() would be
cloned (implicitly orphaning) prior to queueing for reassembly. As such,
when the IPv6 message is eventually reassembled, the skb->sk for all
fragments would be NULL. After that commit was introduced, rather than
cloning, the original skbs were queued directly without orphaning. The
end result is that all frags except for the first and last may have a
socket attached.

This commit explicitly orphans such skbs during nf_ct_frag6_gather() to
prevent BUG_ON(skb->sk) during a later call to ip6_fragment().

kernel BUG at net/ipv6/ip6_output.c:631!
[...]
Call Trace:
 <IRQ>
 [<ffffffff810be8f7>] ? __lock_acquire+0x927/0x20a0
 [<ffffffffa042c7c0>] ? do_output.isra.28+0x1b0/0x1b0 [openvswitch]
 [<ffffffff810bb8a2>] ? __lock_is_held+0x52/0x70
 [<ffffffffa042c587>] ovs_fragment+0x1f7/0x280 [openvswitch]
 [<ffffffff810bdab5>] ? mark_held_locks+0x75/0xa0
 [<ffffffff817be416>] ? _raw_spin_unlock_irqrestore+0x36/0x50
 [<ffffffff81697ea0>] ? dst_discard_out+0x20/0x20
 [<ffffffff81697e80>] ? dst_ifdown+0x80/0x80
 [<ffffffffa042c703>] do_output.isra.28+0xf3/0x1b0 [openvswitch]
 [<ffffffffa042d279>] do_execute_actions+0x709/0x12c0 [openvswitch]
 [<ffffffffa04340a4>] ? ovs_flow_stats_update+0x74/0x1e0 [openvswitch]
 [<ffffffffa04340d1>] ? ovs_flow_stats_update+0xa1/0x1e0 [openvswitch]
 [<ffffffff817be387>] ? _raw_spin_unlock+0x27/0x40
 [<ffffffffa042de75>] ovs_execute_actions+0x45/0x120 [openvswitch]
 [<ffffffffa0432d65>] ovs_dp_process_packet+0x85/0x150 [openvswitch]
 [<ffffffff817be387>] ? _raw_spin_unlock+0x27/0x40
 [<ffffffffa042def4>] ovs_execute_actions+0xc4/0x120 [openvswitch]
 [<ffffffffa0432d65>] ovs_dp_process_packet+0x85/0x150 [openvswitch]
 [<ffffffffa04337f2>] ? key_extract+0x442/0xc10 [openvswitch]
 [<ffffffffa043b26d>] ovs_vport_receive+0x5d/0xb0 [openvswitch]
 [<ffffffff810be8f7>] ? __lock_acquire+0x927/0x20a0
 [<ffffffff810be8f7>] ? __lock_acquire+0x927/0x20a0
 [<ffffffff810be8f7>] ? __lock_acquire+0x927/0x20a0
 [<ffffffff817be416>] ? _raw_spin_unlock_irqrestore+0x36/0x50
 [<ffffffffa043c11d>] internal_dev_xmit+0x6d/0x150 [openvswitch]
 [<ffffffffa043c0b5>] ? internal_dev_xmit+0x5/0x150 [openvswitch]
 [<ffffffff8168fb5f>] dev_hard_start_xmit+0x2df/0x660
 [<ffffffff8168f5ea>] ? validate_xmit_skb.isra.105.part.106+0x1a/0x2b0
 [<ffffffff81690925>] __dev_queue_xmit+0x8f5/0x950
 [<ffffffff81690080>] ? __dev_queue_xmit+0x50/0x950
 [<ffffffff810bdab5>] ? mark_held_locks+0x75/0xa0
 [<ffffffff81690990>] dev_queue_xmit+0x10/0x20
 [<ffffffff8169a418>] neigh_resolve_output+0x178/0x220
 [<ffffffff81752759>] ? ip6_finish_output2+0x219/0x7b0
 [<ffffffff81752759>] ip6_finish_output2+0x219/0x7b0
 [<ffffffff817525a5>] ? ip6_finish_output2+0x65/0x7b0
 [<ffffffff816cde2b>] ? ip_idents_reserve+0x6b/0x80
 [<ffffffff8175488f>] ? ip6_fragment+0x93f/0xc50
 [<ffffffff81754af1>] ip6_fragment+0xba1/0xc50
 [<ffffffff81752540>] ? ip6_flush_pending_frames+0x40/0x40
 [<ffffffff81754c6b>] ip6_finish_output+0xcb/0x1d0
 [<ffffffff81754dcf>] ip6_output+0x5f/0x1a0
 [<ffffffff81754ba0>] ? ip6_fragment+0xc50/0xc50
 [<ffffffff81797fbd>] ip6_local_out+0x3d/0x80
 [<ffffffff817554df>] ip6_send_skb+0x2f/0xc0
 [<ffffffff817555bd>] ip6_push_pending_frames+0x4d/0x50
 [<ffffffff817796cc>] icmpv6_push_pending_frames+0xac/0xe0
 [<ffffffff8177a4be>] icmpv6_echo_reply+0x42e/0x500
 [<ffffffff8177acbf>] icmpv6_rcv+0x4cf/0x580
 [<ffffffff81755ac7>] ip6_input_finish+0x1a7/0x690
 [<ffffffff81755925>] ? ip6_input_finish+0x5/0x690
 [<ffffffff817567a0>] ip6_input+0x30/0xa0
 [<ffffffff81755920>] ? ip6_rcv_finish+0x1a0/0x1a0
 [<ffffffff817557ce>] ip6_rcv_finish+0x4e/0x1a0
 [<ffffffff8175640f>] ipv6_rcv+0x45f/0x7c0
 [<ffffffff81755fe6>] ? ipv6_rcv+0x36/0x7c0
 [<ffffffff81755780>] ? ip6_make_skb+0x1c0/0x1c0
 [<ffffffff8168b649>] __netif_receive_skb_core+0x229/0xb80
 [<ffffffff810bdab5>] ? mark_held_locks+0x75/0xa0
 [<ffffffff8168c07f>] ? process_backlog+0x6f/0x230
 [<ffffffff8168bfb6>] __netif_receive_skb+0x16/0x70
 [<ffffffff8168c088>] process_backlog+0x78/0x230
 [<ffffffff8168c0ed>] ? process_backlog+0xdd/0x230
 [<ffffffff8168db43>] net_rx_action+0x203/0x480
 [<ffffffff810bdab5>] ? mark_held_locks+0x75/0xa0
 [<ffffffff817c156e>] __do_softirq+0xde/0x49f
 [<ffffffff81752768>] ? ip6_finish_output2+0x228/0x7b0
 [<ffffffff817c070c>] do_softirq_own_stack+0x1c/0x30
 <EOI>
 [<ffffffff8106f88b>] do_softirq.part.18+0x3b/0x40
 [<ffffffff8106f946>] __local_bh_enable_ip+0xb6/0xc0
 [<ffffffff81752791>] ip6_finish_output2+0x251/0x7b0
 [<ffffffff81754af1>] ? ip6_fragment+0xba1/0xc50
 [<ffffffff816cde2b>] ? ip_idents_reserve+0x6b/0x80
 [<ffffffff8175488f>] ? ip6_fragment+0x93f/0xc50
 [<ffffffff81754af1>] ip6_fragment+0xba1/0xc50
 [<ffffffff81752540>] ? ip6_flush_pending_frames+0x40/0x40
 [<ffffffff81754c6b>] ip6_finish_output+0xcb/0x1d0
 [<ffffffff81754dcf>] ip6_output+0x5f/0x1a0
 [<ffffffff81754ba0>] ? ip6_fragment+0xc50/0xc50
 [<ffffffff81797fbd>] ip6_local_out+0x3d/0x80
 [<ffffffff817554df>] ip6_send_skb+0x2f/0xc0
 [<ffffffff817555bd>] ip6_push_pending_frames+0x4d/0x50
 [<ffffffff81778558>] rawv6_sendmsg+0xa28/0xe30
 [<ffffffff81719097>] ? inet_sendmsg+0xc7/0x1d0
 [<ffffffff817190d6>] inet_sendmsg+0x106/0x1d0
 [<ffffffff81718fd5>] ? inet_sendmsg+0x5/0x1d0
 [<ffffffff8166d078>] sock_sendmsg+0x38/0x50
 [<ffffffff8166d4d6>] SYSC_sendto+0xf6/0x170
 [<ffffffff8100201b>] ? trace_hardirqs_on_thunk+0x1b/0x1d
 [<ffffffff8166e38e>] SyS_sendto+0xe/0x10
 [<ffffffff817bebe5>] entry_SYSCALL_64_fastpath+0x18/0xa8
Code: 06 48 83 3f 00 75 26 48 8b 87 d8 00 00 00 2b 87 d0 00 00 00 48 39 d0 72 14 8b 87 e4 00 00 00 83 f8 01 75 09 48 83 7f 18 00 74 9a <0f> 0b 41 8b 86 cc 00 00 00 49 8#
RIP  [<ffffffff8175468a>] ip6_fragment+0x73a/0xc50
 RSP <ffff880072803120>

Fixes: 029f7f3b87 ("netfilter: ipv6: nf_defrag: avoid/free clone
operations")
Reported-by: Daniele Di Proietto <diproiettod@vmware.com>
Signed-off-by: Joe Stringer <joe@ovn.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-04-21 13:42:05 -04:00
Florian Westphal adff6c6560 netfilter: connlabels: change nf_connlabels_get bit arg to 'highest used'
nf_connlabel_set() takes the bit number that we would like to set.
nf_connlabels_get() however took the number of bits that we want to
support.

So e.g. nf_connlabels_get(32) support bits 0 to 31, but not 32.
This changes nf_connlabels_get() to take the highest bit that we want
to set.

Callers then don't have to cope with a potential integer wrap
when using nf_connlabels_get(bit + 1) anymore.

Current callers are fine, this change is only to make folloup
nft ct label set support simpler.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-04-18 20:39:48 +02:00
David S. Miller 0c84ea17ff Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for you net tree,
they are:

1) There was a race condition between parallel save/swap and delete,
   which resulted a kernel crash due to the increase ref for save, swap,
   wrong ref decrease operations. Reported and fixed by Vishwanath Pai.

2) OVS should call into CT NAT for packets of new expected connections only
   when the conntrack state is persisted with the 'commit' option to the
   OVS CT action. From Jarno Rajahalme.

3) Resolve kconfig dependencies with new OVS NAT support. From Arnd Bergmann.

4) Early validation of entry->target_offset to make sure it doesn't take us
   out from the blob, from Florian Westphal.

5) Again early validation of entry->next_offset to make sure it doesn't take
   out from the blob, also from Florian.

6) Check that entry->target_offset is always of of sizeof(struct xt_entry)
   for unconditional entries, when checking both from check_underflow()
   and when checking for loops in mark_source_chains(), again from
   Florian.

7) Fix inconsistent behaviour in nfnetlink_queue when
   NFQA_CFG_F_FAIL_OPEN is set and netlink_unicast() fails due to buffer
   overrun, we have to reinject the packet as the user expects.

8) Enforce nul-terminated table names from getsockopt GET_ENTRIES
   requests.

9) Don't assume skb->sk is set from nft_bridge_reject and synproxy,
   this fixes a recent update of the code to namespaceify
   ip_default_ttl, patch from Liping Zhang.

This batch comes with four patches to validate x_tables blobs coming
from userspace. CONFIG_USERNS exposes the x_tables interface to
unpriviledged users and to be honest this interface never received the
attention for this move away from the CAP_NET_ADMIN domain. Florian is
working on another round with more patches with more sanity checks, so
expect a bit more Netfilter fixes in this development cycle than usual.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-28 15:38:59 -04:00
Arnd Bergmann 99b7248e2a openvswitch: call only into reachable nf-nat code
The openvswitch code has gained support for calling into the
nf-nat-ipv4/ipv6 modules, however those can be loadable modules
in a configuration in which openvswitch is built-in, leading
to link errors:

net/built-in.o: In function `__ovs_ct_lookup':
:(.text+0x2cc2c8): undefined reference to `nf_nat_icmp_reply_translation'
:(.text+0x2cc66c): undefined reference to `nf_nat_icmpv6_reply_translation'

The dependency on (!NF_NAT || NF_NAT) prevents similar issues,
but NF_NAT is set to 'y' if any of the symbols selecting
it are built-in, but the link error happens when any of them
are modular.

A second issue is that even if CONFIG_NF_NAT_IPV6 is built-in,
CONFIG_NF_NAT_IPV4 might be completely disabled. This is unlikely
to be useful in practice, but the driver currently only handles
IPv6 being optional.

This patch improves the Kconfig dependency so that openvswitch
cannot be built-in if either of the two other symbols are set
to 'm', and it replaces the incorrect #ifdef in ovs_ct_nat_execute()
with two "if (IS_ENABLED())" checks that should catch all corner
cases also make the code more readable.

The same #ifdef exists ovs_ct_nat_to_attr(), where it does not
cause a link error, but for consistency I'm changing it the same
way.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Fixes: 05752523e5 ("openvswitch: Interface with NAT.")
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-03-28 17:58:59 +02:00
Jarno Rajahalme 5745b0be05 openvswitch: Fix checking for new expected connections.
OVS should call into CT NAT for packets of new expected connections only
when the conntrack state is persisted with the 'commit' option to the
OVS CT action.  The test for this condition is doubly wrong, as the CT
status field is ANDed with the bit number (IPS_EXPECTED_BIT) rather
than the mask (IPS_EXPECTED), and due to the wrong assumption that the
expected bit would apply only for the first (i.e., 'new') packet of a
connection, while in fact the expected bit remains on for the lifetime of
an expected connection.  The 'ctinfo' value IP_CT_RELATED derived from
the ct status can be used instead, as it is only ever applicable to
the 'new' packets of the expected connection.

Fixes: 05752523e5 ('openvswitch: Interface with NAT.')
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-03-28 17:58:51 +02:00
Haishuang Yan ac71b46efd openvswitch: Use proper buffer size in nla_memcpy
For the input parameter count, it's better to use the size
of destination buffer size, as nla_memcpy would take into
account the length of the source netlink attribute when
a data is copied from an attribute.

Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-28 11:37:14 -04:00
Jarno Rajahalme 05752523e5 openvswitch: Interface with NAT.
Extend OVS conntrack interface to cover NAT.  New nested
OVS_CT_ATTR_NAT attribute may be used to include NAT with a CT action.
A bare OVS_CT_ATTR_NAT only mangles existing and expected connections.
If OVS_NAT_ATTR_SRC or OVS_NAT_ATTR_DST is included within the nested
attributes, new (non-committed/non-confirmed) connections are mangled
according to the rest of the nested attributes.

The corresponding OVS userspace patch series includes test cases (in
tests/system-traffic.at) that also serve as example uses.

This work extends on a branch by Thomas Graf at
https://github.com/tgraf/ovs/tree/nat.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-03-14 23:47:29 +01:00
Jarno Rajahalme 28b6e0c1ac openvswitch: Delay conntrack helper call for new connections.
There is no need to help connections that are not confirmed, so we can
delay helping new connections to the time when they are confirmed.
This change is needed for NAT support, and having this as a separate
patch will make the following NAT patch a bit easier to review.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-03-14 23:47:29 +01:00
Jarno Rajahalme 5b6b929376 openvswitch: Handle NF_REPEAT in conntrack action.
Repeat the nf_conntrack_in() call when it returns NF_REPEAT.  This
avoids dropping a SYN packet re-opening an existing TCP connection.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-03-14 23:47:29 +01:00
Jarno Rajahalme 289f225349 openvswitch: Find existing conntrack entry after upcall.
Add a new function ovs_ct_find_existing() to find an existing
conntrack entry for which this packet was already applied to.  This is
only to be called when there is evidence that the packet was already
tracked and committed, but we lost the ct reference due to an
userspace upcall.

ovs_ct_find_existing() is called from skb_nfct_cached(), which can now
hide the fact that the ct reference may have been lost due to an
upcall.  This allows ovs_ct_commit() to be simplified.

This patch is needed by later "openvswitch: Interface with NAT" patch,
as we need to be able to pass the packet through NAT using the
original ct reference also after the reference is lost after an
upcall.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-03-14 23:47:28 +01:00
Jarno Rajahalme 394e910e90 openvswitch: Update the CT state key only after nf_conntrack_in().
Only a successful nf_conntrack_in() call can effect a connection state
change, so it suffices to update the key only after the
nf_conntrack_in() returns.

This change is needed for the later NAT patches.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-03-14 23:47:28 +01:00
Jarno Rajahalme 9f13ded8d3 openvswitch: Add commentary to conntrack.c
This makes the code easier to understand and the following patches
more focused.

Signed-off-by: Jarno Rajahalme <jarno@ovn.org>
Acked-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2016-03-14 23:47:27 +01:00