7107 Commits

Author SHA1 Message Date
Jiri Benc
b194f30c61 lwtunnel: remove source and destination UDP port config option
The UDP tunnel config is asymmetric wrt. to the ports used. The source and
destination ports from one direction of the tunnel are not related to the
ports of the other direction. We need to be able to respond to ARP requests
using the correct ports without involving routing.

As the consequence, UDP ports need to be fixed property of the tunnel
interface and cannot be set per route. Remove the ability to set ports per
route. This is still okay to do, as no kernel has been released with these
attributes yet.

Note that the ability to specify source and destination ports is preserved
for other users of the lwtunnel API which don't use routes for tunnel key
specification (like openvswitch).

If in the future we rework ARP handling to allow port specification, the
attributes can be added back.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-24 14:31:37 -07:00
Jiri Benc
63d008a4e9 ipv4: send arp replies to the correct tunnel
When using ip lwtunnels, the additional data for xmit (basically, the actual
tunnel to use) are carried in ip_tunnel_info either in dst->lwtstate or in
metadata dst. When replying to ARP requests, we need to send the reply to
the same tunnel the request came from. This means we need to construct
proper metadata dst for ARP replies.

We could perform another route lookup to get a dst entry with the correct
lwtstate. However, this won't always ensure that the outgoing tunnel is the
same as the incoming one, and it won't work anyway for IPv4 duplicate
address detection.

The only thing to do is to "reverse" the ip_tunnel_info.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-24 14:31:36 -07:00
Eric Dumazet
675ee231d9 tcp: add proper TS val into RST packets
RST packets sent on behalf of TCP connections with TS option (RFC 7323
TCP timestamps) have incorrect TS val (set to 0), but correct TS ecr.

A > B: Flags [S], seq 0, win 65535, options [mss 1000,nop,nop,TS val 100
ecr 0], length 0
B > A: Flags [S.], seq 2444755794, ack 1, win 28960, options [mss
1460,nop,nop,TS val 7264344 ecr 100], length 0
A > B: Flags [.], ack 1, win 65535, options [nop,nop,TS val 110 ecr
7264344], length 0

B > A: Flags [R.], seq 1, ack 1, win 28960, options [nop,nop,TS val 0
ecr 110], length 0

We need to call skb_mstamp_get() to get proper TS val,
derived from skb->skb_mstamp

Note that RFC 1323 was advocating to not send TS option in RST segment,
but RFC 7323 recommends the opposite :

  Once TSopt has been successfully negotiated, that is both <SYN> and
  <SYN,ACK> contain TSopt, the TSopt MUST be sent in every non-<RST>
  segment for the duration of the connection, and SHOULD be sent in an
  <RST> segment (see Section 5.2 for details)

Note this RFC recommends to send TS val = 0, but we believe it is
premature : We do not know if all TCP stacks are properly
handling the receive side :

   When an <RST> segment is
   received, it MUST NOT be subjected to the PAWS check by verifying an
   acceptable value in SEG.TSval, and information from the Timestamps
   option MUST NOT be used to update connection state information.
   SEG.TSecr MAY be used to provide stricter <RST> acceptance checks.

In 5 years, if/when all TCP stack are RFC 7323 ready, we might consider
to decide to send TS val = 0, if it buys something.

Fixes: 7faee5c0d514 ("tcp: remove TCP_SKB_CB(skb)->when")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-23 14:24:07 -07:00
David S. Miller
99cb99aa05 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/IPVS updates for your net-next tree
in this 4.4 development cycle, they are:

1) Schedule ICMP traffic to IPVS instances, this introduces a new schedule_icmp
   proc knob to enable/disable it. By default is off to retain the old
   behaviour. Patchset from Alex Gartrell.

I'm also including what Alex originally said for the record:

"The configuration of ipvs at Facebook is relatively straightforward.  All
ipvs instances bgp advertise a set of VIPs and the network prefers the
nearest one or uses ECMP in the event of a tie.  For the uninitiated, ECMP
deterministically and statelessly load balances by hashing the packet
(usually a 5-tuple of protocol, saddr, daddr, sport, and dport) and using
that number as an index (basic hash table type logic).

The problem is that ICMP packets (which contain really important
information like whether or not an MTU has been exceeded) will get a
different hash value and may end up at a different ipvs instance.  With no
information about where to route these packets, they are dropped, creating
ICMP black holes and breaking Path MTU discovery.  Suddenly, my mom's
pictures can't load and I'm fielding midday calls that I want nothing to do
with.

To address this, this patch set introduces the ability to schedule icmp
packets which is gated by a sysctl net.ipv4.vs.schedule_icmp.  If set to 0,
the old behavior is maintained -- otherwise ICMP packets are scheduled."

2) Add another proc entry to ignore tunneled packets to avoid routing loops
   from IPVS, also from Alex.

3) Fifteen patches from Eric Biederman to:

* Stop passing nf_hook_ops as parameter to the hook and use the state hook
  object instead all around the netfilter code, so only the private data
  pointer is passed to the registered hook function.

* Now that we've got state->net, propagate the netns pointer to netfilter hook
  clients to avoid its computation over and over again. A good example of how
  this has been simplified is the former TEE target (now nf_dup infrastructure)
  since it has killed the ugly pick_net() function.

There's another round of netns updates from Eric Biederman making the line. To
avoid the patchbomb again to almost all the networking mailing list (that is 84
patches) I'd suggest we send you a pull request with no patches or let me know
if you prefer a better way.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-22 13:11:43 -07:00
Eric Dumazet
29c6852602 inet: fix races in reqsk_queue_hash_req()
Before allowing lockless LISTEN processing, we need to make
sure to arm the SYN_RECV timer before the req socket is visible
in hash tables.

Also, req->rsk_hash should be written before we set rsk_refcnt
to a non zero value.

Fixes: fa76ce7328b2 ("inet: get rid of central tcp/dccp listener timer")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ying Cai <ycai@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-21 16:32:29 -07:00
Eric Dumazet
ed2e923945 tcp/dccp: fix timewait races in timer handling
When creating a timewait socket, we need to arm the timer before
allowing other cpus to find it. The signal allowing cpus to find
the socket is setting tw_refcnt to non zero value.

As we set tw_refcnt in __inet_twsk_hashdance(), we therefore need to
call inet_twsk_schedule() first.

This also means we need to remove tw_refcnt changes from
inet_twsk_schedule() and let the caller handle it.

Note that because we use mod_timer_pinned(), we have the guarantee
the timer wont expire before we set tw_refcnt as we run in BH context.

To make things more readable I introduced inet_twsk_reschedule() helper.

When rearming the timer, we can use mod_timer_pending() to make sure
we do not rearm a canceled timer.

Note: This bug can possibly trigger if packets of a flow can hit
multiple cpus. This does not normally happen, unless flow steering
is broken somehow. This explains this bug was spotted ~5 months after
its introduction.

A similar fix is needed for SYN_RECV sockets in reqsk_queue_hash_req(),
but will be provided in a separate patch for proper tracking.

Fixes: 789f558cfb36 ("tcp/dccp: get rid of central timewait timer")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Ying Cai <ycai@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-21 16:32:29 -07:00
Yuchung Cheng
f9b9958229 tcp: send loss probe after 1s if no RTT available
This patch makes TLP to use 1 sec timer by default when RTT is
not available due to SYN/ACK retransmission or SYN cookies.

Prior to this change, the lack of RTT prevents TLP so the first
data packets sent can only be recovered by fast recovery or RTO.
If the fast recovery fails to trigger the RTO is 3 second when
SYN/ACK is retransmitted. With this patch we can trigger fast
recovery in 1sec instead.

Note that we need to check Fast Open more properly. A Fast Open
connection could be (accepted then) closed before it receives
the final ACK of 3WHS so the state is FIN_WAIT_1. Without the
new check, TLP will retransmit FIN instead of SYN/ACK.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Nandita Dukkipati <nanditad@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-21 16:19:01 -07:00
Yuchung Cheng
0f1c28ae74 tcp: usec resolution SYN/ACK RTT
Currently SYN/ACK RTT is measured in jiffies. For LAN the SYN/ACK
RTT is often measured as 0ms or sometimes 1ms, which would affect
RTT estimation and min RTT samping used by some congestion control.

This patch improves SYN/ACK RTT to be usec resolution if platform
supports it. While the timestamping of SYN/ACK is done in request
sock, the RTT measurement is carefully arranged to avoid storing
another u64 timestamp in tcp_sock.

For regular handshake w/o SYNACK retransmission, the RTT is sampled
right after the child socket is created and right before the request
sock is released (tcp_check_req() in tcp_minisocks.c)

For Fast Open the child socket is already created when SYN/ACK was
sent, the RTT is sampled in tcp_rcv_state_process() after processing
the final ACK an right before the request socket is released.

If the SYN/ACK was retransmistted or SYN-cookie was used, we rely
on TCP timestamps to measure the RTT. The sample is taken at the
same place in tcp_rcv_state_process() after the timestamp values
are validated in tcp_validate_incoming(). Note that we do not store
TS echo value in request_sock for SYN-cookies, because the value
is already stored in tp->rx_opt used by tcp_ack_update_rtt().

One side benefit is that the RTT measurement now happens before
initializing congestion control (of the passive side). Therefore
the congestion control can use the SYN/ACK RTT.

Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-21 16:19:01 -07:00
Nicolas Dichtel
bc22a0e2ea iptunnel: make rx/tx bytes counters consistent
This was already done a long time ago in
commit 64194c31a0b6 ("inet: Make tunnel RX/TX byte counters more consistent")
but tx path was broken (at least since 3.10).

Before the patch the gre header was included on tx.

After the patch:
$ ping -c1 192.168.0.121 ; ip -s l ls dev gre1
PING 192.168.0.121 (192.168.0.121) 56(84) bytes of data.
64 bytes from 192.168.0.121: icmp_req=1 ttl=64 time=2.95 ms

--- 192.168.0.121 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 2.955/2.955/2.955/0.000 ms
7: gre1@NONE: <POINTOPOINT,NOARP,UP,LOWER_UP> mtu 1468 qdisc noqueue state UNKNOWN mode DEFAULT group default
    link/gre 10.16.0.249 peer 10.16.0.121
    RX: bytes  packets  errors  dropped overrun mcast
    84         1        0       0       0       0
    TX: bytes  packets  errors  dropped carrier collsns
    84         1        0       0       0       0

Reported-by: Julien Meunier <julien.meunier@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-20 22:36:22 -07:00
Nikola Forró
0315e38270 net: Fix behaviour of unreachable, blackhole and prohibit routes
Man page of ip-route(8) says following about route types:

  unreachable - these destinations are unreachable.  Packets are dis‐
  carded and the ICMP message host unreachable is generated.  The local
  senders get an EHOSTUNREACH error.

  blackhole - these destinations are unreachable.  Packets are dis‐
  carded silently.  The local senders get an EINVAL error.

  prohibit - these destinations are unreachable.  Packets are discarded
  and the ICMP message communication administratively prohibited is
  generated.  The local senders get an EACCES error.

In the inet6 address family, this was correct, except the local senders
got ENETUNREACH error instead of EHOSTUNREACH in case of unreachable route.
In the inet address family, all three route types generated ICMP message
net unreachable, and the local senders got ENETUNREACH error.

In both address families all three route types now behave consistently
with documentation.

Signed-off-by: Nikola Forró <nforro@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-20 21:45:08 -07:00
Eric W. Biederman
c7af6483b9 netfilter: Pass net into nf_xfrm_me_harder
Instead of calling dev_net on a likley looking network device
pass state->net into nf_xfrm_me_harder.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 22:00:22 +02:00
Eric W. Biederman
06198b34a3 netfilter: Pass priv instead of nf_hook_ops to netfilter hooks
Only pass the void *priv parameter out of the nf_hook_ops.  That is
all any of the functions are interested now, and by limiting what is
passed it becomes simpler to change implementation details.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 22:00:16 +02:00
Eric W. Biederman
a31f1adc09 netfilter: nf_conntrack: Add a struct net parameter to l4_pkt_to_tuple
As gre does not have the srckey in the packet gre_pkt_to_tuple
needs to perform a lookup in it's per network namespace tables.

Pass in the proper network namespace to all pkt_to_tuple
implementations to ensure gre (and any similar protocols) can get this
right.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 22:00:04 +02:00
Eric W. Biederman
206e8c0075 netfilter: Pass net to nf_dup_ipv4 and nf_dup_ipv6
This allows them to stop guessing the network namespace with pick_net.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 21:59:11 +02:00
Eric W. Biederman
686c9b5080 netfilter: x_tables: Use par->net instead of computing from the passed net devices
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 21:58:25 +02:00
Eric W. Biederman
156c196f60 netfilter: x_tables: Pass struct net in xt_action_param
As xt_action_param lives on the stack this does not bloat any
persistent data structures.

This is a first step in making netfilter code that needs to know
which network namespace it is executing in simpler.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 21:58:14 +02:00
Eric W. Biederman
6aa187f21c netfilter: nf_tables: kill nft_pktinfo.ops
- Add nft_pktinfo.pf to replace ops->pf
- Add nft_pktinfo.hook to replace ops->hooknum

This simplifies the code, makes it more readable, and likely reduces
cache line misses.  Maintainability is enhanced as the details of
nft_hook_ops are of no concern to the recpients of nft_pktinfo.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 21:58:01 +02:00
Eric W. Biederman
082a758f04 inet netfilter: Prefer state->hook to ops->hooknum
The values of nf_hook_state.hook and nf_hook_ops.hooknum must be the
same by definition.

We are more likely to access the fields in nf_hook_state over the
fields in nf_hook_ops so with a little luck this results in
fewer cache line misses, and slightly more consistent code.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 21:57:51 +02:00
Eric W. Biederman
6cb8ff3f1a inet netfilter: Remove hook from ip6t_do_table, arp_do_table, ipt_do_table
The values of ops->hooknum and state->hook are guaraneted to be equal
making the hook argument to ip6t_do_table, arp_do_table, and
ipt_do_table is unnecessary. Remove the unnecessary hook argument.

In the callers use state->hook instead of ops->hooknum for clarity and
to reduce the number of cachelines the callers touch.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2015-09-18 21:57:43 +02:00
Eric Dumazet
c2e7204d18 tcp_cubic: do not set epoch_start in the future
Tracking idle time in bictcp_cwnd_event() is imprecise, as epoch_start
is normally set at ACK processing time, not at send time.

Doing a proper fix would need to add an additional state variable,
and does not seem worth the trouble, given CUBIC bug has been there
forever before Jana noticed it.

Let's simply not set epoch_start in the future, otherwise
bictcp_update() could overflow and CUBIC would again
grow cwnd too fast.

This was detected thanks to a packetdrill test Neal wrote that was flaky
before applying this fix.

Fixes: 30927520dbae ("tcp_cubic: better follow cubic curve after idle period")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Cc: Jana Iyengar <jri@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 22:35:07 -07:00
David Ahern
bde6f9ded1 net: Initialize table in fib result
Sergey, Richard and Fabio reported an oops in ip_route_input_noref. e.g., from Richard:

[    0.877040] BUG: unable to handle kernel NULL pointer dereference at 0000000000000056
[    0.877597] IP: [<ffffffff8155b5e2>] ip_route_input_noref+0x1a2/0xb00
[    0.877597] PGD 3fa14067 PUD 3fa6e067 PMD 0
[    0.877597] Oops: 0000 [#1] SMP
[    0.877597] Modules linked in: virtio_net virtio_pci virtio_ring virtio
[    0.877597] CPU: 1 PID: 119 Comm: ifconfig Not tainted 4.2.0+ #1
[    0.877597] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[    0.877597] task: ffff88003fab0bc0 ti: ffff88003faa8000 task.ti: ffff88003faa8000
[    0.877597] RIP: 0010:[<ffffffff8155b5e2>]  [<ffffffff8155b5e2>] ip_route_input_noref+0x1a2/0xb00
[    0.877597] RSP: 0018:ffff88003ed03ba0  EFLAGS: 00010202
[    0.877597] RAX: 0000000000000046 RBX: 00000000ffffff8f RCX: 0000000000000020
[    0.877597] RDX: ffff88003fab50b8 RSI: 0000000000000200 RDI: ffffffff8152b4b8
[    0.877597] RBP: ffff88003ed03c50 R08: 0000000000000000 R09: 0000000000000000
[    0.877597] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88003fab6f00
[    0.877597] R13: ffff88003fab5000 R14: 0000000000000000 R15: ffffffff81cb5600
[    0.877597] FS:  00007f6de5751700(0000) GS:ffff88003ed00000(0000) knlGS:0000000000000000
[    0.877597] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    0.877597] CR2: 0000000000000056 CR3: 000000003fa6d000 CR4: 00000000000006e0
[    0.877597] Stack:
[    0.877597]  0000000000000000 0000000000000046 ffff88003fffa600 ffff88003ed03be0
[    0.877597]  ffff88003f9e2c00 697da8c0017da8c0 ffff880000000000 000000000007fd00
[    0.877597]  0000000000000000 0000000000000046 0000000000000000 0000000400000000
[    0.877597] Call Trace:
[    0.877597]  <IRQ>
[    0.877597]  [<ffffffff812bfa1f>] ? cpumask_next_and+0x2f/0x40
[    0.877597]  [<ffffffff8158e13c>] arp_process+0x39c/0x690
[    0.877597]  [<ffffffff8158e57e>] arp_rcv+0x13e/0x170
[    0.877597]  [<ffffffff8151feec>] __netif_receive_skb_core+0x60c/0xa00
[    0.877597]  [<ffffffff81515795>] ? __build_skb+0x25/0x100
[    0.877597]  [<ffffffff81515795>] ? __build_skb+0x25/0x100
[    0.877597]  [<ffffffff81521ff6>] __netif_receive_skb+0x16/0x70
[    0.877597]  [<ffffffff81522078>] netif_receive_skb_internal+0x28/0x90
[    0.877597]  [<ffffffff8152288f>] napi_gro_receive+0x7f/0xd0
[    0.877597]  [<ffffffffa0017906>] virtnet_receive+0x256/0x910 [virtio_net]
[    0.877597]  [<ffffffffa0017fd8>] virtnet_poll+0x18/0x80 [virtio_net]
[    0.877597]  [<ffffffff815234cd>] net_rx_action+0x1dd/0x2f0
[    0.877597]  [<ffffffff81053228>] __do_softirq+0x98/0x260
[    0.877597]  [<ffffffff8164969c>] do_softirq_own_stack+0x1c/0x30

The root cause is use of res.table uninitialized.

Thanks to Nikolay for noticing the uninitialized use amongst the maze of
gotos.

As Nikolay pointed out the second initialization is not required to fix
the oops, but rather to fix a related problem where a valid lookup should
be invalidated before creating the rth entry.

Fixes: b7503e0cdb5d ("net: Add FIB table id to rtable")
Reported-by: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Reported-by: Richard Alpe <richard.alpe@ericsson.com>
Reported-by: Fabio Estevam <festevam@gmail.com>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Tested-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 21:34:08 -07:00
Junwei Zhang
f6c53334d6 net: only check perm protocol when register proto
The permanent protocol nodes are at the head of the list,
So only need check all these nodes.

No matter the new node is permanent or not,
insert the new node after the last permanent protocol node,

If the new node conflicts with existing permanent node,
return error.

Signed-off-by: Martin Zhang <martinbj2008@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 21:02:59 -07:00
Eric Dumazet
58d607d3e5 tcp: provide skb->hash to synack packets
In commit b73c3d0e4f0e ("net: Save TX flow hash in sock and set in skbuf
on xmit"), Tom provided a l4 hash to most outgoing TCP packets.

We'd like to provide one as well for SYNACK packets, so that all packets
of a given flow share same txhash, to later enable bonding driver to
also use skb->hash to perform slave selection.

Note that a SYNACK retransmit shuffles the tx hash, as Tom did
in commit 265f94ff54d62 ("net: Recompute sk_txhash on negative routing
advice") for established sockets.

This has nice effect making TCP flows resilient to some kind of black
holes, even at connection establish phase.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Cc: Mahesh Bandewar <maheshb@google.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 21:01:04 -07:00
Eric W. Biederman
be10de0a32 netfilter: Add blank lines in callers of netfilter hooks
In code review it was noticed that I had failed to add some blank lines
in places where they are customarily used.  Taking a second look at the
code I have to agree blank lines would be nice so I have added them
here.

Reported-by:  Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:37 -07:00
Eric W. Biederman
0c4b51f005 netfilter: Pass net into okfn
This is immediately motivated by the bridge code that chains functions that
call into netfilter.  Without passing net into the okfns the bridge code would
need to guess about the best expression for the network namespace to process
packets in.

As net is frequently one of the first things computed in continuation functions
after netfilter has done it's job passing in the desired network namespace is in
many cases a code simplification.

To support this change the function dst_output_okfn is introduced to
simplify passing dst_output as an okfn.  For the moment dst_output_okfn
just silently drops the struct net.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:37 -07:00
Eric W. Biederman
9dff2c966a netfilter: Use nf_hook_state.net
Instead of saying "net = dev_net(state->in?state->in:state->out)"
just say "state->net".  As that information is now availabe,
much less confusing and much less error prone.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:37 -07:00
Eric W. Biederman
29a26a5680 netfilter: Pass struct net into the netfilter hooks
Pass a network namespace parameter into the netfilter hooks.  At the
call site of the netfilter hooks the path a packet is taking through
the network stack is well known which allows the network namespace to
be easily and reliabily.

This allows the replacement of magic code like
"dev_net(state->in?:state->out)" that appears at the start of most
netfilter hooks with "state->net".

In almost all cases the network namespace passed in is derived
from the first network device passed in, guaranteeing those
paths will not see any changes in practice.

The exceptions are:
xfrm/xfrm_output.c:xfrm_output_resume()         xs_net(skb_dst(skb)->xfrm)
ipvs/ip_vs_xmit.c:ip_vs_nat_send_or_cont()      ip_vs_conn_net(cp)
ipvs/ip_vs_xmit.c:ip_vs_send_or_cont()          ip_vs_conn_net(cp)
ipv4/raw.c:raw_send_hdrinc()                    sock_net(sk)
ipv6/ip6_output.c:ip6_xmit()			sock_net(sk)
ipv6/ndisc.c:ndisc_send_skb()                   dev_net(skb->dev) not dev_net(dst->dev)
ipv6/raw.c:raw6_send_hdrinc()                   sock_net(sk)
br_netfilter_hooks.c:br_nf_pre_routing_finish() dev_net(skb->dev) before skb->dev is set to nf_bridge->physindev

In all cases these exceptions seem to be a better expression for the
network namespace the packet is being processed in then the historic
"dev_net(in?in:out)".  I am documenting them in case something odd
pops up and someone starts trying to track down what happened.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:37 -07:00
Eric W. Biederman
f9e4306fd8 arp: Introduce arp_xmit_finish
The function dev_queue_xmit_skb_sk is unncessary and very confusing.
Introduce arp_xmit_finish to remove the need for dev_queue_xmit_skb_sk,
and have arp_xmit_finish call dev_queue_xmit.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:35 -07:00
Eric W. Biederman
758ccac8e7 ipv4: Only compute net once in ipmr_forward_finish
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:34 -07:00
Eric W. Biederman
38184b3b07 ipv4: Only compute net once in ip_rcv_finish
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:34 -07:00
Eric W. Biederman
4ba1bf4292 ipv4: Only compute net once in ip_finish_output2
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:34 -07:00
Eric W. Biederman
9479b0af48 ipv4: Explicitly compute net in ip_fragment
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:34 -07:00
Eric W. Biederman
26a949dbd5 ipv4: Only compute net once in ip_do_fragment
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:34 -07:00
Eric W. Biederman
cc4c851e4b ipv4: Don't recompute net in ipmr_queue_xmit
Calling dev_net(dev) for is just silly.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:33 -07:00
Eric W. Biederman
88f5cc2458 ipv4: Remember the net in ip_output and ip_mc_output
This is a prepatory patch to passing net int the netfilter hooks,
where net will be used again.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:33 -07:00
Eric W. Biederman
e707766ce0 ipv4: Compute net once in ip_rcv
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:33 -07:00
Eric W. Biederman
f8e1ac7912 ipv4: Compute net once in ip_forward_finish
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:33 -07:00
Eric W. Biederman
fcad0ac2da ipv4: Compute net once in ip_forward
Compute struct net from the input device in ip_forward before it is
used.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:33 -07:00
Eric W. Biederman
5a70649e0d net: Merge dst_output and dst_output_sk
Add a sock paramter to dst_output making dst_output_sk superfluous.
Add a skb->sk parameter to all of the callers of dst_output
Have the callers of dst_output_sk call dst_output.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 17:18:32 -07:00
David Ahern
58189ca7b2 net: Fix vti use case with oif in dst lookups
Steffen reported that the recent change to add oif to dst lookups breaks
the VTI use case. The problem is that with the oif set in the flow struct
the comparison to the nh_oif is triggered. Fix by splitting the
FLOWI_FLAG_VRFSRC into 2 flags -- one that triggers the vrf device cache
bypass (FLOWI_FLAG_VRFSRC) and another telling the lookup to not compare
nh oif (FLOWI_FLAG_SKIP_NH_OIF).

Fixes: 42a7b32b73d6 ("xfrm: Add oif to dst lookups")

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 16:36:34 -07:00
Sowmini Varadhan
d5566fd72e rtnetlink: RTEXT_FILTER_SKIP_STATS support to avoid dumping inet/inet6 stats
Many commonly used functions like getifaddrs() invoke RTM_GETLINK
to dump the interface information, and do not need the
the AF_INET6 statististics that are always returned by default
from rtnl_fill_ifinfo().

Computing the statistics can be an expensive operation that impacts
scaling, so it is desirable to avoid this if the information is
not needed.

This patch adds a the RTEXT_FILTER_SKIP_STATS extended info flag that
can be passed with netlink_request() to avoid statistics computation
for the ifinfo path.

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-15 15:25:02 -07:00
David Ahern
c36ba6603a net: Allow user to get table id from route lookup
rt_fill_info which is called for 'route get' requests hardcodes the
table id as RT_TABLE_MAIN which is not correct when multiple tables
are used. Use the newly added table id in the rtable to send back
the correct table similar to what is done for IPv6.

To maintain current ABI a new request flag, RTM_F_LOOKUP_TABLE, is
added to indicate the actual table is wanted versus the hardcoded
response.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-15 12:01:41 -07:00
David Ahern
b7503e0cdb net: Add FIB table id to rtable
Add the FIB table id to rtable to make the information available for
IPv4 as it is for IPv6.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-15 12:01:41 -07:00
David Ahern
d08c4f3554 net: Refactor rtable initialization
All callers to rt_dst_alloc have nearly the same initialization following
a successful allocation. Consolidate it into rt_dst_alloc.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-15 12:01:40 -07:00
Eric Dumazet
30927520db tcp_cubic: better follow cubic curve after idle period
Jana Iyengar found an interesting issue on CUBIC :

The epoch is only updated/reset initially and when experiencing losses.
The delta "t" of now - epoch_start can be arbitrary large after app idle
as well as the bic_target. Consequentially the slope (inverse of
ca->cnt) would be really large, and eventually ca->cnt would be
lower-bounded in the end to 2 to have delayed-ACK slow-start behavior.

This particularly shows up when slow_start_after_idle is disabled
as a dangerous cwnd inflation (1.5 x RTT) after few seconds of idle
time.

Jana initial fix was to reset epoch_start if app limited,
but Neal pointed out it would ask the CUBIC algorithm to recalculate the
curve so that we again start growing steeply upward from where cwnd is
now (as CUBIC does just after a loss). Ideally we'd want the cwnd growth
curve to be the same shape, just shifted later in time by the amount of
the idle period.

Reported-by: Jana Iyengar <jri@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Sangtae Ha <sangtae.ha@gmail.com>
Cc: Lawrence Brakmo <lawrence@brakmo.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-10 10:58:33 -07:00
Neal Cardwell
05c5a46d71 tcp: generate CA_EVENT_TX_START on data frames
Issuing a CC TX_START event on control frames like pure ACK
is a waste of time, as a CC should not care.

Following patch needs this change, as we want CUBIC to properly track
idle time at a low cost, with a single TX_START being generated.

Yuchung might slightly refine the condition triggering TX_START
on a followup patch.

Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Cc: Jana Iyengar <jri@google.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Sangtae Ha <sangtae.ha@gmail.com>
Cc: Lawrence Brakmo <lawrence@brakmo.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-10 10:58:33 -07:00
Phil Sutter
f53de1e9a4 net: ipv6: use common fib_default_rule_pref
This switches IPv6 policy routing to use the shared
fib_default_rule_pref() function of IPv4 and DECnet. It is also used in
multicast routing for IPv4 as well as IPv6.

The motivation for this patch is a complaint about iproute2 behaving
inconsistent between IPv4 and IPv6 when adding policy rules: Formerly,
IPv6 rules were assigned a fixed priority of 0x3FFF whereas for IPv4 the
assigned priority value was decreased with each rule added.

Since then all users of the default_pref field have been converted to
assign the generic function fib_default_rule_pref(), fib_nl_newrule()
may just use it directly instead. Therefore get rid of the function
pointer altogether and make fib_default_rule_pref() static, as it's not
used outside fib_rules.c anymore.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-09 14:19:50 -07:00
Daniel Borkmann
a82b0e6391 netfilter: nf_dup{4, 6}: fix build error when nf_conntrack disabled
While testing various Kconfig options on another issue, I found that
the following one triggers as well on allmodconfig and nf_conntrack
disabled:

  net/ipv4/netfilter/nf_dup_ipv4.c: In function ‘nf_dup_ipv4’:
  net/ipv4/netfilter/nf_dup_ipv4.c:72:20: error: ‘nf_skb_duplicated’ undeclared (first use in this function)
    if (this_cpu_read(nf_skb_duplicated))
  [...]
  net/ipv6/netfilter/nf_dup_ipv6.c: In function ‘nf_dup_ipv6’:
  net/ipv6/netfilter/nf_dup_ipv6.c:66:20: error: ‘nf_skb_duplicated’ undeclared (first use in this function)
    if (this_cpu_read(nf_skb_duplicated))

Fix it by including directly the header where it is defined.

Fixes: bbde9fc1824a ("netfilter: factor out packet duplication for IPv4/IPv6")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-02 16:28:06 -07:00
David Ahern
9b8ff51822 net: Make table id type u32
A number of VRF patches used 'int' for table id. It should be u32 to be
consistent with the rest of the stack.

Fixes:
4e3c89920cd3a ("net: Introduce VRF related flags and helpers")
15be405eb2ea9 ("net: Add inet_addr lookup by table")
30bbaa1950055 ("net: Fix up inet_addr_type checks")
021dd3b8a142d ("net: Add routes to the table associated with the device")
dc028da54ed35 ("inet: Move VRF table lookup to inlined function")
f6d3c19274c74 ("net: FIB tracepoints")

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 14:32:44 -07:00
Daniel Borkmann
c3a8d94746 tcp: use dctcp if enabled on the route to the initiator
Currently, the following case doesn't use DCTCP, even if it should:
A responder has f.e. Cubic as system wide default, but for a specific
route to the initiating host, DCTCP is being set in RTAX_CC_ALGO. The
initiating host then uses DCTCP as congestion control, but since the
initiator sets ECT(0), tcp_ecn_create_request() doesn't set ecn_ok,
and we have to fall back to Reno after 3WHS completes.

We were thinking on how to solve this in a minimal, non-intrusive
way without bloating tcp_ecn_create_request() needlessly: lets cache
the CA ecn option flag in RTAX_FEATURES. In other words, when ECT(0)
is set on the SYN packet, set ecn_ok=1 iff route RTAX_FEATURES
contains the unexposed (internal-only) DST_FEATURE_ECN_CA. This allows
to only do a single metric feature lookup inside tcp_ecn_create_request().

Joint work with Florian Westphal.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-31 12:34:00 -07:00