Commit Graph

4216 Commits

Author SHA1 Message Date
Eric Dumazet 93d05d4a32 net: provide generic busy polling to all NAPI drivers
NAPI drivers no longer need to observe a particular protocol
to benefit from busy polling (CONFIG_NET_RX_BUSY_POLL=y)

napi_hash_add() and napi_hash_del() are automatically called
from core networking stack, respectively from
netif_napi_add() and netif_napi_del()

This patch depends on free_netdev() and netif_napi_del() being
called from process context, which seems to be the norm.

Drivers might still prefer to call napi_hash_del() on their
own, since they might combine all the rcu grace periods into
a single one, knowing their NAPI structures lifetime, while
core networking stack has no idea of a possible combining.

Once this patch proves to not bring serious regressions,
we will cleanup drivers to either remove napi_hash_del()
or provide appropriate rcu grace periods combining.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-18 16:17:42 -05:00
Eric Dumazet 34cbe27e81 net: napi_hash_del() returns a boolean status
napi_hash_del() will soon be used from both drivers (if they want)
or core networking stack.

Callers are responsibles to ensure an RCU grace period is respected
before freeing napi structure : napi_hash_del() can signal if
this RCU grace period is needed or not.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-18 16:17:42 -05:00
Eric Dumazet 6180d9de61 net: move napi_hash[] into read mostly section
We do not often add/delete a napi context.
Moving napi_hash[] into read mostly section avoids potential false sharing.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-18 16:17:42 -05:00
Eric Dumazet d64b5e85bf net: add netif_tx_napi_add()
netif_tx_napi_add() is a variant of netif_napi_add()

It should be used by drivers that use a napi structure
to exclusively poll TX.

We do not want to add this kind of napi in napi_hash[] in following
patches, adding generic busy polling to all NAPI drivers.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-18 16:17:41 -05:00
Eric Dumazet 93f93a4404 net: move skb_mark_napi_id() into core networking stack
We would like to automatically provide busy polling support
to all NAPI drivers, without them having to implement anything.

skb_mark_napi_id() can be called from napi_gro_receive() and
napi_get_frags().

Few drivers are still calling skb_mark_napi_id() because
they use netif_receive_skb(). They should eventually call
napi_gro_receive() instead. I will leave this to drivers
maintainers.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-18 16:17:41 -05:00
Eric Dumazet ce6aea93f7 net: network drivers no longer need to implement ndo_busy_poll()
Instead of having to implement complex ndo_busy_poll() method,
drivers can simply rely on NAPI poll logic.

Busy polling gains are mainly coming from polling itself,
not on exact details on how we poll the device.

ndo_busy_poll() if implemented can avoid touching
napi state, but it adds extra synchronization between
normal napi->poll() and busy poll handler, slowing down
the common path (non busy polling) with extra atomic operations.
In practice few drivers ever got busy poll because of the complexity.

We could go one step further, and make busy polling
available for all NAPI drivers, but this would require
that all netif_napi_del() calls are done in process context
so that we can call synchronize_rcu().
Full audit would be required.

Before this is done, a driver still needs to call :

- skb_mark_napi_id() for each skb provided to the stack.
- napi_hash_add() and napi_hash_del() to allocate a napi_id per napi struct.
- Make sure RCU grace period is respected after napi_hash_del() before
  memory containing napi structure is freed.

Followup patch implements busy poll for mlx5 driver as an example.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-18 16:17:39 -05:00
Eric Dumazet 2a028ecb76 net: allow BH servicing in sk_busy_loop()
Instead of blocking BH in whole sk_busy_loop(), block them
only around ->ndo_busy_poll() calls.

This has many benefits.

1) allow tunneled traffic to use busy poll as well as native traffic.
   Tunnels handlers usually call netif_rx() and depend on net_rx_action()
   being run (from sofirq handler)

2) allow RFS/RPS being used (sending IPI to other cpus if needed)

3) use the 'lets burn cpu cycles' budget to do useful work
   (like TX completions, timers, RCU callbacks...)

4) reduce BH latencies, making busy poll a better citizen.

Tested:

Tested with SIT tunnel

lpaa5:~# echo 0 >/proc/sys/net/core/busy_read
lpaa5:~# ./netperf -H 2002:af6:786::1 -t TCP_RR
MIGRATED TCP REQUEST/RESPONSE TEST from ::0 (::) port 0 AF_INET6 to 2002:af6:786::1 () port 0 AF_INET6 : first burst 0
Local /Remote
Socket Size   Request  Resp.   Elapsed  Trans.
Send   Recv   Size     Size    Time     Rate
bytes  Bytes  bytes    bytes   secs.    per sec

16384  87380  1        1       10.00    37373.93
16384  87380

Now enable busy poll on both hosts

lpaa5:~# echo 70 >/proc/sys/net/core/busy_read
lpaa6:~# echo 70 >/proc/sys/net/core/busy_read

lpaa5:~# ./netperf -H 2002:af6:786::1 -t TCP_RR
MIGRATED TCP REQUEST/RESPONSE TEST from ::0 (::) port 0 AF_INET6 to 2002:af6:786::1 () port 0 AF_INET6 : first burst 0
Local /Remote
Socket Size   Request  Resp.   Elapsed  Trans.
Send   Recv   Size     Size    Time     Rate
bytes  Bytes  bytes    bytes   secs.    per sec

16384  87380  1        1       10.00    58314.77
16384  87380

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-18 16:17:38 -05:00
Eric Dumazet 02d62e86fe net: un-inline sk_busy_loop()
There is really little gain from inlining this big function.
We'll soon make it even bigger in following patches.

This means we no longer need to export napi_by_id()

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-18 16:17:38 -05:00
Eric Dumazet 52bd2d62ce net: better skb->sender_cpu and skb->napi_id cohabitation
skb->sender_cpu and skb->napi_id share a common storage,
and we had various bugs about this.

We had to call skb_sender_cpu_clear() in some places to
not leave a prior skb->napi_id and fool netdev_pick_tx()

As suggested by Alexei, we could split the space so that
these errors can not happen.

0 value being reserved as the common (not initialized) value,
let's reserve [1 .. NR_CPUS] range for valid sender_cpu,
and [NR_CPUS+1 .. ~0U] for valid napi_id.

This will allow proper busy polling support over tunnels.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-18 16:17:37 -05:00
Nikolay Aleksandrov 17b85d29e8 net/core: revert "net: fix __netdev_update_features return.." and add comment
This reverts commit 00ee592717 ("net: fix __netdev_update_features return
on ndo_set_features failure")
and adds a comment explaining why it's okay to return a value other than
0 upon error. Some drivers might actually change flags and return an
error so it's better to fire a spurious notification rather than miss
these.

CC: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-17 15:25:45 -05:00
Hannes Frederic Sowa b22b941b2c rtnetlink: fix frame size warning in rtnl_fill_ifinfo
Fix the following warning:

  CC      net/core/rtnetlink.o
net/core/rtnetlink.c: In function ‘rtnl_fill_ifinfo’:
net/core/rtnetlink.c:1308:1: warning: the frame size of 2864 bytes is larger than 2048 bytes [-Wframe-larger-than=]
 }
 ^
by splitting up the huge rtnl_fill_ifinfo into some smaller ones, so we
don't have the huge frame allocations at the same time.

Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-17 15:25:44 -05:00
Martin Zhang 19125c1a4f net: use skb_clone to avoid alloc_pages failure.
1. new skb only need dst and ip address(v4 or v6).
2. skb_copy may need high order pages, which is very rare on long running server.

Signed-off-by: Junwei Zhang <linggao.zjw@alibaba-inc.com>
Signed-off-by: Martin Zhang <martinbj2008@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-17 15:25:44 -05:00
Vlad Yasevich a6e18ff111 vlan: Fix untag operations of stacked vlans with REORDER_HEADER off
When we have multiple stacked vlan devices all of which have
turned off REORDER_HEADER flag, the untag operation does not
locate the ethernet addresses correctly for nested vlans.
The reason is that in case of REORDER_HEADER flag being off,
the outer vlan headers are put back and the mac_len is adjusted
to account for the presense of the header.  Then, the subsequent
untag operation, for the next level vlan, always use VLAN_ETH_HLEN
to locate the begining of the ethernet header and that ends up
being a multiple of 4 bytes short of the actuall beginning
of the mac header (the multiple depending on the how many vlan
encapsulations ethere are).

As a reslult, if there are multiple levles of vlan devices
with REODER_HEADER being off, the recevied packets end up
being dropped.

To solve this, we use skb->mac_len as the offset.  The value
is always set on receive path and starts out as a ETH_HLEN.
The value is also updated when the vlan header manupations occur
so we know it will be correct.

Signed-off-by: Vladislav Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-17 14:38:35 -05:00
Bjørn Mork 88ad4175b2 net/core: use netdev name in warning if no parent
A recent flaw in the netdev feature setting resulted in warnings
like this one from VLAN interfaces:

 WARNING: CPU: 1 PID: 4975 at net/core/dev.c:2419 skb_warn_bad_offload+0xbc/0xcb()
 : caps=(0x00000000001b5820, 0x00000000001b5829) len=2782 data_len=0 gso_size=1348 gso_type=16 ip_summed=3

The ":" is supposed to be preceded by a driver name, but in this
case it is an empty string since the device has no parent.

There are many types of network devices without a parent. The
anonymous warnings for these devices can be hard to debug.  Log
the network device name instead in these cases to assist further
debugging.

This is mostly similar to how __netdev_printk() handles orphan
devices.

Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-16 16:21:48 -05:00
Nikolay Aleksandrov 00ee592717 net: fix __netdev_update_features return on ndo_set_features failure
If ndo_set_features fails __netdev_update_features() will return -1 but
this is wrong because it is expected to return 0 if no features were
changed (see netdev_update_features()), which will cause a netdev
notifier to be called without any actual changes. Fix this by returning
0 if ndo_set_features fails.

Fixes: 6cb6a27c45 ("net: Call netdev_features_change() from netdev_update_features()")
CC: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-16 14:56:03 -05:00
Nikolay Aleksandrov 5f8dc33e8e net: fix feature changes on devices without ndo_set_features
When __netdev_update_features() was updated to ensure some features are
disabled on new lower devices, an error was introduced for devices which
don't have the ndo_set_features() method set. Before we'll just set the
new features, but now we return an error and don't set them. Fix this by
returning the old behaviour and setting err to 0 when ndo_set_features
is not present.

Fixes: e7868a85e1 ("net/core: ensure features get disabled on new lower devs")
CC: Jarod Wilson <jarod@redhat.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Ido Schimmel <idosch@mellanox.com>
CC: Sander Eikelenboom <linux@eikelenboom.it>
CC: Andy Gospodarek <gospo@cumulusnetworks.com>
CC: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Andy Gospodarek <gospo@cumulusnetworks.com>
Reviewed-by: Jarod Wilson <jarod@redhat.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Dave Young <dyoung@redhat.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-16 14:56:03 -05:00
Linus Torvalds 2df4ee78d0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull networking fixes from David Miller:

 1) Fix null deref in xt_TEE netfilter module, from Eric Dumazet.

 2) Several spots need to get to the original listner for SYN-ACK
    packets, most spots got this ok but some were not.  Whilst covering
    the remaining cases, create a helper to do this.  From Eric Dumazet.

 3) Missiing check of return value from alloc_netdev() in CAIF SPI code,
    from Rasmus Villemoes.

 4) Don't sleep while != TASK_RUNNING in macvtap, from Vlad Yasevich.

 5) Use after free in mvneta driver, from Justin Maggard.

 6) Fix race on dst->flags access in dst_release(), from Eric Dumazet.

 7) Add missing ZLIB_INFLATE dependency for new qed driver.  From Arnd
    Bergmann.

 8) Fix multicast getsockopt deadlock, from WANG Cong.

 9) Fix deadlock in btusb, from Kuba Pawlak.

10) Some ipv6_add_dev() failure paths were not cleaning up the SNMP6
    counter state.  From Sabrina Dubroca.

11) Fix packet_bind() race, which can cause lost notifications, from
    Francesco Ruggeri.

12) Fix MAC restoration in qlcnic driver during bonding mode changes,
    from Jarod Wilson.

13) Revert bridging forward delay change which broke libvirt and other
    userspace things, from Vlad Yasevich.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (65 commits)
  Revert "bridge: Allow forward delay to be cfgd when STP enabled"
  bpf_trace: Make dependent on PERF_EVENTS
  qed: select ZLIB_INFLATE
  net: fix a race in dst_release()
  net: mvneta: Fix memory use after free.
  net: Documentation: Fix default value tcp_limit_output_bytes
  macvtap: Resolve possible __might_sleep warning in macvtap_do_read()
  mvneta: add FIXED_PHY dependency
  net: caif: check return value of alloc_netdev
  net: hisilicon: NET_VENDOR_HISILICON should depend on HAS_DMA
  drivers: net: xgene: fix RGMII 10/100Mb mode
  netfilter: nft_meta: use skb_to_full_sk() helper
  net_sched: em_meta: use skb_to_full_sk() helper
  sched: cls_flow: use skb_to_full_sk() helper
  netfilter: xt_owner: use skb_to_full_sk() helper
  smack: use skb_to_full_sk() helper
  net: add skb_to_full_sk() helper and use it in selinux_netlbl_skbuff_setsid()
  bpf: doc: correct arch list for supported eBPF JIT
  dwc_eth_qos: Delete an unnecessary check before the function call "of_node_put"
  bonding: fix panic on non-ARPHRD_ETHER enslave failure
  ...
2015-11-10 18:11:41 -08:00
Eric Dumazet d69bbf88c8 net: fix a race in dst_release()
Only cpu seeing dst refcount going to 0 can safely
dereference dst->flags.

Otherwise an other cpu might already have freed the dst.

Fixes: 27b75c95f1 ("net: avoid RCU for NOCACHE dst")
Reported-by: Greg Thelen <gthelen@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-09 21:55:48 -05:00
Mel Gorman d0164adc89 mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd
__GFP_WAIT has been used to identify atomic context in callers that hold
spinlocks or are in interrupts.  They are expected to be high priority and
have access one of two watermarks lower than "min" which can be referred
to as the "atomic reserve".  __GFP_HIGH users get access to the first
lower watermark and can be called the "high priority reserve".

Over time, callers had a requirement to not block when fallback options
were available.  Some have abused __GFP_WAIT leading to a situation where
an optimisitic allocation with a fallback option can access atomic
reserves.

This patch uses __GFP_ATOMIC to identify callers that are truely atomic,
cannot sleep and have no alternative.  High priority users continue to use
__GFP_HIGH.  __GFP_DIRECT_RECLAIM identifies callers that can sleep and
are willing to enter direct reclaim.  __GFP_KSWAPD_RECLAIM to identify
callers that want to wake kswapd for background reclaim.  __GFP_WAIT is
redefined as a caller that is willing to enter direct reclaim and wake
kswapd for background reclaim.

This patch then converts a number of sites

o __GFP_ATOMIC is used by callers that are high priority and have memory
  pools for those requests. GFP_ATOMIC uses this flag.

o Callers that have a limited mempool to guarantee forward progress clear
  __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall
  into this category where kswapd will still be woken but atomic reserves
  are not used as there is a one-entry mempool to guarantee progress.

o Callers that are checking if they are non-blocking should use the
  helper gfpflags_allow_blocking() where possible. This is because
  checking for __GFP_WAIT as was done historically now can trigger false
  positives. Some exceptions like dm-crypt.c exist where the code intent
  is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to
  flag manipulations.

o Callers that built their own GFP flags instead of starting with GFP_KERNEL
  and friends now also need to specify __GFP_KSWAPD_RECLAIM.

The first key hazard to watch out for is callers that removed __GFP_WAIT
and was depending on access to atomic reserves for inconspicuous reasons.
In some cases it may be appropriate for them to use __GFP_HIGH.

The second key hazard is callers that assembled their own combination of
GFP flags instead of starting with something like GFP_KERNEL.  They may
now wish to specify __GFP_KSWAPD_RECLAIM.  It's almost certainly harmless
if it's missed in most cases as other activity will wake kswapd.

Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Vitaly Wool <vitalywool@gmail.com>
Cc: Rik van Riel <riel@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-11-06 17:50:42 -08:00
Jarod Wilson e7868a85e1 net/core: ensure features get disabled on new lower devs
With moving netdev_sync_lower_features() after the .ndo_set_features
calls, I neglected to verify that devices added *after* a flag had been
disabled on an upper device were properly added with that flag disabled as
well. This currently happens, because we exit __netdev_update_features()
when we see dev->features == features for the upper dev. We can retain the
optimization of leaving without calling .ndo_set_features with a bit of
tweaking and a goto here.

Fixes: fd867d51f8 ("net/core: generic support for disabling netdev features down stack")
CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <gospo@cumulusnetworks.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Nikolay Aleksandrov <razor@blackwall.org>
CC: Michal Kubecek <mkubecek@suse.cz>
CC: Alexander Duyck <alexander.duyck@gmail.com>
CC: netdev@vger.kernel.org
Reported-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-04 21:56:00 -05:00
Jarod Wilson 5ba3f7d61a net/core: fix for_each_netdev_feature
As pointed out by Nikolay and further explained by Geert, the initial
for_each_netdev_feature macro was broken, as feature would get set outside
of the block of code it was intended to run in, thus only ever working for
the first feature bit in the mask. While less pretty this way, this is
tested and confirmed functional with multiple feature bits set in
NETIF_F_UPPER_DISABLES.

[root@dell-per730-01 ~]# ethtool -K bond0 lro off
...
[  242.761394] bond0: Disabling feature 0x0000000000008000 on lower dev p5p2.
[  243.552178] bnx2x 0000:06:00.1 p5p2: using MSI-X  IRQs: sp 74  fp[0] 76 ... fp[7] 83
[  244.353978] bond0: Disabling feature 0x0000000000008000 on lower dev p5p1.
[  245.147420] bnx2x 0000:06:00.0 p5p1: using MSI-X  IRQs: sp 62  fp[0] 64 ... fp[7] 71

[root@dell-per730-01 ~]# ethtool -K bond0 gro off
...
[  251.925645] bond0: Disabling feature 0x0000000000004000 on lower dev p5p2.
[  252.713693] bnx2x 0000:06:00.1 p5p2: using MSI-X  IRQs: sp 74  fp[0] 76 ... fp[7] 83
[  253.499085] bond0: Disabling feature 0x0000000000004000 on lower dev p5p1.
[  254.290922] bnx2x 0000:06:00.0 p5p1: using MSI-X  IRQs: sp 62  fp[0] 64 ... fp[7] 71

Fixes: fd867d51f ("net/core: generic support for disabling netdev features down stack")
CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <gospo@cumulusnetworks.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Nikolay Aleksandrov <razor@blackwall.org>
CC: Michal Kubecek <mkubecek@suse.cz>
CC: Alexander Duyck <alexander.duyck@gmail.com>
CC: Geert Uytterhoeven <geert@linux-m68k.org>
CC: netdev@vger.kernel.org
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-03 11:29:57 -05:00
Stefan Sørensen 5f94c943d5 ptp: Change ptp_class to a proper bitmask
Change the definition of PTP_CLASS_L2 to not have any bits overlapping with
the other defined protocol values, allowing the PTP_CLASS_* definitions to
be for simple filtering on packet type.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-03 11:08:22 -05:00
Jarod Wilson fd867d51f8 net/core: generic support for disabling netdev features down stack
There are some netdev features, which when disabled on an upper device,
such as a bonding master or a bridge, must be disabled and cannot be
re-enabled on underlying devices.

This is a rework of an earlier more heavy-handed appraoch, which simply
disables and prevents re-enabling of netdev features listed in a new
define in include/net/netdev_features.h, NETIF_F_UPPER_DISABLES. Any upper
device that disables a flag in that feature mask, the disabling will
propagate down the stack, and any lower device that has any upper device
with one of those flags disabled should not be able to enable said flag.

Initially, only LRO is included for proof of concept, and because this
code effectively does the same thing as dev_disable_lro(), though it will
also activate from the ethtool path, which was one of the goals here.

[root@dell-per730-01 ~]# ethtool -k bond0 |grep large
large-receive-offload: on
[root@dell-per730-01 ~]# ethtool -k p5p1 |grep large
large-receive-offload: on
[root@dell-per730-01 ~]# ethtool -K bond0 lro off
[root@dell-per730-01 ~]# ethtool -k bond0 |grep large
large-receive-offload: off
[root@dell-per730-01 ~]# ethtool -k p5p1 |grep large
large-receive-offload: off

dmesg dump:

[ 1033.277986] bond0: Disabling feature 0x0000000000008000 on lower dev p5p2.
[ 1034.067949] bnx2x 0000:06:00.1 p5p2: using MSI-X  IRQs: sp 74  fp[0] 76 ... fp[7] 83
[ 1034.753612] bond0: Disabling feature 0x0000000000008000 on lower dev p5p1.
[ 1035.591019] bnx2x 0000:06:00.0 p5p1: using MSI-X  IRQs: sp 62  fp[0] 64 ... fp[7] 71

This has been successfully tested with bnx2x, qlcnic and netxen network
cards as slaves in a bond interface. Turning LRO on or off on the master
also turns it on or off on each of the slaves, new slaves are added with
LRO in the same state as the master, and LRO can't be toggled on the
slaves.

Also, this should largely remove the need for dev_disable_lro(), and most,
if not all, of its call sites can be replaced by simply making sure
NETIF_F_LRO isn't included in the relevant device's feature flags.

Note that this patch is driven by bug reports from users saying it was
confusing that bonds and slaves had different settings for the same
features, and while it won't be 100% in sync if a lower device doesn't
support a feature like LRO, I think this is a good step in the right
direction.

CC: "David S. Miller" <davem@davemloft.net>
CC: Eric Dumazet <edumazet@google.com>
CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <gospo@cumulusnetworks.com>
CC: Jiri Pirko <jiri@resnulli.us>
CC: Nikolay Aleksandrov <razor@blackwall.org>
CC: Michal Kubecek <mkubecek@suse.cz>
CC: Alexander Duyck <alexander.duyck@gmail.com>
CC: netdev@vger.kernel.org
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-02 23:41:31 -05:00
Eric Dumazet 9e17f8a475 net: make skb_set_owner_w() more robust
skb_set_owner_w() is called from various places that assume
skb->sk always point to a full blown socket (as it changes
sk->sk_wmem_alloc)

We'd like to attach skb to request sockets, and in the future
to timewait sockets as well. For these kind of pseudo sockets,
we need to take a traditional refcount and use sock_edemux()
as the destructor.

It is now time to un-inline skb_set_owner_w(), being too big.

Fixes: ca6fb06518 ("tcp: attach SYNACK messages to request sockets instead of listener")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Bisected-by: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-02 16:28:49 -05:00
Hannes Frederic Sowa 080a270f5a sock: don't enable netstamp for af_unix sockets
netstamp_needed is toggled for all socket families if they request
timestamping. But some protocols don't need the lower-layer timestamping
code at all. This patch starts disabling it for af-unix.

E.g. systemd enables timestamping during boot-up on the journald af-unix
sockets, thus causing the system to globally enable timestamping in the
lower networking stack. Still, it is very probable that timestamping
gets activated, by e.g. dhclient or various NTP implementations.

Reported-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-27 19:39:14 -07:00
emmanuel.grumbach@intel.com 8941faa161 net: tso: add support for IPv6
Adding IPv6 for the TSO helper API is trivial:
* Don't play with the id (which doesn't exist in IPv6)
* Correctly update the payload_len (don't include the
  length of the IP header itself)

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-26 22:24:22 -07:00
David S. Miller ba3e2084f2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/ipv6/xfrm6_output.c
	net/openvswitch/flow_netlink.c
	net/openvswitch/vport-gre.c
	net/openvswitch/vport-vxlan.c
	net/openvswitch/vport.c
	net/openvswitch/vport.h

The openvswitch conflicts were overlapping changes.  One was
the egress tunnel info fix in 'net' and the other was the
vport ->send() op simplification in 'net-next'.

The xfrm6_output.c conflicts was also a simplification
overlapping a bug fix.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-24 06:54:12 -07:00
Hiroshi Shimamoto dd461d6aa8 if_link: Add control trust VF
Add netlink directives and ndo entry to trust VF user.

This controls the special permission of VF user.
The administrator will dedicatedly trust VF user to use some features
which impacts security and/or performance.

The administrator never turn it on unless VF user is fully trusted.

CC: Sy Jong Choi <sy.jong.choi@intel.com>
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Acked-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2015-10-23 05:44:28 -07:00
Pravin B Shelar fc4099f172 openvswitch: Fix egress tunnel info.
While transitioning to netdev based vport we broke OVS
feature which allows user to retrieve tunnel packet egress
information for lwtunnel devices.  Following patch fixes it
by introducing ndo operation to get the tunnel egress info.
Same ndo operation can be used for lwtunnel devices and compat
ovs-tnl-vport devices. So after adding such device operation
we can remove similar operation from ovs-vport.

Fixes: 614732eaa1 ("openvswitch: Use regular VXLAN net_device device").
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-22 19:39:25 -07:00
Arad, Ronen b1974ed05e netlink: Rightsize IFLA_AF_SPEC size calculation
if_nlmsg_size() overestimates the minimum allocation size of netlink
dump request (when called from rtnl_calcit()) or the size of the
message (when called from rtnl_getlink()). This is because
ext_filter_mask is not supported by rtnl_link_get_af_size() and
rtnl_link_get_size().

The over-estimation is significant when at least one netdev has many
VLANs configured (8 bytes for each configured VLAN).

This patch-set "rightsizes" the protocol specific attribute size
calculation by propagating ext_filter_mask to rtnl_link_get_af_size()
and adding this a argument to get_link_af_size op in rtnl_af_ops.

Bridge module already used filtering aware sizing for notifications.
br_get_link_af_size_filtered() is consistent with the modified
get_link_af_size op so it replaces br_get_link_af_size() in br_af_ops.
br_get_link_af_size() becomes unused and thus removed.

Signed-off-by: Ronen Arad <ronen.arad@intel.com>
Acked-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-21 19:15:20 -07:00
David S. Miller 26440c835f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/usb/asix_common.c
	net/ipv4/inet_connection_sock.c
	net/switchdev/switchdev.c

In the inet_connection_sock.c case the request socket hashing scheme
is completely different in net-next.

The other two conflicts were overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-20 06:08:27 -07:00
Jiri Pirko 573c7ba006 net: introduce pre-change upper device notifier
This newly introduced netdevice notifier is called before actual change
upper happens. That provides a possibility for notifier handlers to
know upper change will happen and react to it, including possibility to
forbid the change. That is valuable for drivers which can check if the
upper device linkage is supported and forbid that in case it is not.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-16 07:15:05 -07:00
Joe Perches 077cb37fcf ethtool: Use kcalloc instead of kmalloc for ethtool_get_strings
It seems that kernel memory can leak into userspace by a
kmalloc, ethtool_get_strings, then copy_to_user sequence.

Avoid this by using kcalloc to zero fill the copied buffer.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-14 19:00:20 -07:00
Eric Dumazet 70da268b56 net: SO_INCOMING_CPU setsockopt() support
SO_INCOMING_CPU as added in commit 2c8c56e15d was a getsockopt() command
to fetch incoming cpu handling a particular TCP flow after accept()

This commits adds setsockopt() support and extends SO_REUSEPORT selection
logic : If a TCP listener or UDP socket has this option set, a packet is
delivered to this socket only if CPU handling the packet matches the specified
one.

This allows to build very efficient TCP servers, using one listener per
RX queue, as the associated TCP listener should only accept flows handled
in softirq by the same cpu.
This provides optimal NUMA behavior and keep cpu caches hot.

Note that __inet_lookup_listener() still has to iterate over the list of
all listeners. Following patch puts sk_refcnt in a different cache line
to let this iteration hit only shared and read mostly cache lines.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-12 19:28:20 -07:00
Edward Jee f28ea365cd sock: support per-packet fwmark
It's useful to allow users to set fwmark for an individual packet,
without changing the socket state. The function this patch adds in
sock layer can be used by the protocols that need such a feature.

Signed-off-by: Edward Hyunkoo Jee <edjee@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-12 19:25:21 -07:00
Alexei Starovoitov 1be7f75d16 bpf: enable non-root eBPF programs
In order to let unprivileged users load and execute eBPF programs
teach verifier to prevent pointer leaks.
Verifier will prevent
- any arithmetic on pointers
  (except R10+Imm which is used to compute stack addresses)
- comparison of pointers
  (except if (map_value_ptr == 0) ... )
- passing pointers to helper functions
- indirectly passing pointers in stack to helper functions
- returning pointer from bpf program
- storing pointers into ctx or maps

Spill/fill of pointers into stack is allowed, but mangling
of pointers stored in the stack or reading them byte by byte is not.

Within bpf programs the pointers do exist, since programs need to
be able to access maps, pass skb pointer to LD_ABS insns, etc
but programs cannot pass such pointer values to the outside
or obfuscate them.

Only allow BPF_PROG_TYPE_SOCKET_FILTER unprivileged programs,
so that socket filters (tcpdump), af_packet (quic acceleration)
and future kcm can use it.
tracing and tc cls/act program types still require root permissions,
since tracing actually needs to be able to see all kernel pointers
and tc is for root only.

For example, the following unprivileged socket filter program is allowed:
int bpf_prog1(struct __sk_buff *skb)
{
  u32 index = load_byte(skb, ETH_HLEN + offsetof(struct iphdr, protocol));
  u64 *value = bpf_map_lookup_elem(&my_map, &index);

  if (value)
	*value += skb->len;
  return 0;
}

but the following program is not:
int bpf_prog1(struct __sk_buff *skb)
{
  u32 index = load_byte(skb, ETH_HLEN + offsetof(struct iphdr, protocol));
  u64 *value = bpf_map_lookup_elem(&my_map, &index);

  if (value)
	*value += (u64) skb;
  return 0;
}
since it would leak the kernel address into the map.

Unprivileged socket filter bpf programs have access to the
following helper functions:
- map lookup/update/delete (but they cannot store kernel pointers into them)
- get_random (it's already exposed to unprivileged user space)
- get_smp_processor_id
- tail_call into another socket filter program
- ktime_get_ns

The feature is controlled by sysctl kernel.unprivileged_bpf_disabled.
This toggle defaults to off (0), but can be set true (1).  Once true,
bpf programs and maps cannot be accessed from unprivileged process,
and the toggle cannot be set back to false.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-12 19:13:35 -07:00
Alexei Starovoitov ff936a04e5 bpf: fix cb access in socket filter programs
eBPF socket filter programs may see junk in 'u32 cb[5]' area,
since it could have been used by protocol layers earlier.

For socket filter programs used in af_packet we need to clean
20 bytes of skb->cb area if it could be used by the program.
For programs attached to TCP/UDP sockets we need to save/restore
these 20 bytes, since it's used by protocol layers.

Remove SK_RUN_FILTER macro, since it's no longer used.

Long term we may move this bpf cb area to per-cpu scratch, but that
requires addition of new 'per-cpu load/store' instructions,
so not suitable as a short term fix.

Fixes: d691f9e8d4 ("bpf: allow programs to write to certain skb fields")
Reported-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-11 04:40:05 -07:00
Paul Gortmaker b6191aeeec net/core: make sock_diag.c explicitly non-modular
The Makefile currently controlling compilation of this code lists
it under "obj-y" ...meaning that it currently is not being built as
a module by anyone.

Lets remove the modular code that is essentially orphaned, so that
when reading the driver there is no doubt it is builtin-only.

Since module_init translates to device_initcall in the non-modular
case, the init ordering remains unchanged with this commit.  We can
change to one of the other priority initcalls (subsys?) at any later
date, if desired.

We can't remove module.h since the file uses other module related
stuff even though it is not modular itself.

We move the information from the MODULE_LICENSE tag to the top of the
file, since that information is not captured anywhere else.  The
MODULE_ALIAS_NET_PF_PROTO becomes a no-op in the non modular case, so
it is removed.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Craig Gallek <kraig@google.com>
Cc: netdev@vger.kernel.org
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-09 07:52:27 -07:00
Yaowei Bai 0cbf334376 net/core: lockdep_rtnl_is_held can be boolean
This patch makes lockdep_rtnl_is_held return bool due to this
particular function only using either one or zero as its return
value.

In another patch lockdep_is_held is also made return bool.

No functional change.

Signed-off-by: Yaowei Bai <bywxiaobai@163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-09 07:49:06 -07:00
Daniel Borkmann 3ad0040573 bpf: split state from prandom_u32() and consolidate {c, e}BPF prngs
While recently arguing on a seccomp discussion that raw prandom_u32()
access shouldn't be exposed to unpriviledged user space, I forgot the
fact that SKF_AD_RANDOM extension actually already does it for some time
in cBPF via commit 4cd3675ebf ("filter: added BPF random opcode").

Since prandom_u32() is being used in a lot of critical networking code,
lets be more conservative and split their states. Furthermore, consolidate
eBPF and cBPF prandom handlers to use the new internal PRNG. For eBPF,
bpf_get_prandom_u32() was only accessible for priviledged users, but
should that change one day, we also don't want to leak raw sequences
through things like eBPF maps.

One thought was also to have own per bpf_prog states, but due to ABI
reasons this is not easily possible, i.e. the program code currently
cannot access bpf_prog itself, and copying the rnd_state to/from the
stack scratch space whenever a program uses the prng seems not really
worth the trouble and seems too hacky. If needed, taus113 could in such
cases be implemented within eBPF using a map entry to keep the state
space, or get_random_bytes() could become a second helper in cases where
performance would not be critical.

Both sides can trigger a one-time late init via prandom_init_once() on
the shared state. Performance-wise, there should even be a tiny gain
as bpf_user_rnd_u32() saves one function call. The PRNG needs to live
inside the BPF core since kernels could have a NET-less config as well.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Chema Gonzalez <chema@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-08 05:26:39 -07:00
Hannes Frederic Sowa 46234253b9 net: move net_get_random_once to lib
There's no good reason why users outside of networking should not
be using this facility, f.e. for initializing their seeds.

Therefore, make it accessible from there as get_random_once().

Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-08 05:26:35 -07:00
Daniel Borkmann cfc81b5038 bpf, skb_do_redirect: clear sender_cpu before xmit
Similar to commit c29390c6df ("xps: must clear sender_cpu before
forwarding"), we also need to clear the skb->sender_cpu when moving
from RX to TX via skb_do_redirect() due to the shared location of
napi_id (used on RX) and sender_cpu (used on TX).

Fixes: 27b29f6305 ("bpf: add bpf_redirect() helper")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-08 05:03:08 -07:00
Alexei Starovoitov 6bf0577374 bpf: clear sender_cpu before xmit
Similar to commit c29390c6df ("xps: must clear sender_cpu before forwarding")
the skb->sender_cpu needs to be cleared before xmit.

Fixes: 3896d655f4 ("bpf: introduce bpf_clone_redirect() helper")
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-08 05:02:08 -07:00
Eric W. Biederman ede2059dba dst: Pass net into dst->output
The network namespace is already passed into dst_output pass it into
dst->output lwt->output and friends.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-08 04:27:03 -07:00
David Ahern 16660f0bd9 net: Add support for filtering neigh dump by device index
Add support for filtering neighbor dumps by device by adding the
NDA_IFINDEX attribute to the dump request.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-07 04:12:02 -07:00
Daniel Borkmann bab1899187 bpf, seccomp: prepare for upcoming criu support
The current ongoing effort to dump existing cBPF seccomp filters back
to user space requires to hold the pre-transformed instructions like
we do in case of socket filters from sk_attach_filter() side, so they
can be reloaded in original form at a later point in time by utilities
such as criu.

To prepare for this, simply extend the bpf_prog_create_from_user()
API to hold a flag that tells whether we should store the original
or not. Also, fanout filters could make use of that in future for
things like diag. While fanout filters already use bpf_prog_destroy(),
move seccomp over to them as well to handle original programs when
present.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Tycho Andersen <tycho.andersen@canonical.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Tested-by: Tycho Andersen <tycho.andersen@canonical.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-05 06:47:05 -07:00
Daniel Borkmann 93d08b6966 bpf: fix panic in SO_GET_FILTER with native ebpf programs
When sockets have a native eBPF program attached through
setsockopt(sk, SOL_SOCKET, SO_ATTACH_BPF, ...), and then try to
dump these over getsockopt(sk, SOL_SOCKET, SO_GET_FILTER, ...),
the following panic appears:

  [49904.178642] BUG: unable to handle kernel NULL pointer dereference at (null)
  [49904.178762] IP: [<ffffffff81610fd9>] sk_get_filter+0x39/0x90
  [49904.182000] PGD 86fc9067 PUD 531a1067 PMD 0
  [49904.185196] Oops: 0000 [#1] SMP
  [...]
  [49904.224677] Call Trace:
  [49904.226090]  [<ffffffff815e3d49>] sock_getsockopt+0x319/0x740
  [49904.227535]  [<ffffffff812f59e3>] ? sock_has_perm+0x63/0x70
  [49904.228953]  [<ffffffff815e2fc8>] ? release_sock+0x108/0x150
  [49904.230380]  [<ffffffff812f5a43>] ? selinux_socket_getsockopt+0x23/0x30
  [49904.231788]  [<ffffffff815dff36>] SyS_getsockopt+0xa6/0xc0
  [49904.233267]  [<ffffffff8171b9ae>] entry_SYSCALL_64_fastpath+0x12/0x71

The underlying issue is the very same as in commit b382c08656
("sock, diag: fix panic in sock_diag_put_filterinfo"), that is,
native eBPF programs don't store an original program since this
is only needed in cBPF ones.

However, sk_get_filter() wasn't updated to test for this at the
time when eBPF could be attached. Just throw an error to the user
to indicate that eBPF cannot be dumped over this interface.
That way, it can also be known that a program _is_ attached (as
opposed to just return 0), and a different (future) method needs
to be consulted for a dump.

Fixes: 89aa075832 ("net: sock: allow eBPF programs to be attached to sockets")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-05 06:40:16 -07:00
Eric Dumazet ac8cfc7bb8 tcp: restore fastopen operations
I accidentally cleared fastopenq.max_qlen in reqsk_queue_alloc()
while max_qlen can be set before listen() is called,
using TCP_FASTOPEN socket option for example.

Fixes: 0536fcc039 ("tcp: prepare fastopen code for upcoming listener changes")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-05 03:19:06 -07:00
Eric Dumazet 004a5d0140 net: use sk_fullsock() in __netdev_pick_tx()
SYN_RECV & TIMEWAIT sockets are not full blown, they do not have a
sk_dst_cache pointer.

Fixes: ca6fb06518 ("tcp: attach SYNACK messages to request sockets instead of listener")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-05 02:45:25 -07:00
Eric Dumazet e96f78ab27 tcp/dccp: add SLAB_DESTROY_BY_RCU flag for request sockets
Before letting request sockets being put in TCP/DCCP regular
ehash table, we need to add either :

- SLAB_DESTROY_BY_RCU flag to their kmem_cache
- add RCU grace period before freeing them.

Since we carefully respected the SLAB_DESTROY_BY_RCU protocol
like ESTABLISH and TIMEWAIT sockets, use it here.

req_prot_init() being only used by TCP and DCCP, I did not add
a new slab_flags into their rsk_prot, but reuse prot->slab_flags

Since all reqsk_alloc() users are correctly dealing with a failure,
add the __GFP_NOWARN flag to avoid traces under pressure.

Fixes: 079096f103 ("tcp/dccp: install syn_recv requests into ehash table")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 13:25:20 -07:00
Daniel Borkmann 754f1e6a36 sched, bpf: make skb->priority writable
{cls,act}_bpf can now set the skb->priority from an eBPF program based
on various critera, so that for example classful qdiscs like multiq can
update the skb's priority during enqueue time and further push it down
into subsequent qdiscs.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 05:02:41 -07:00
Daniel Borkmann c46646d048 sched, bpf: add helper for retrieving routing realms
Using routing realms as part of the classifier is quite useful, it
can be viewed as a tag for one or multiple routing entries (think of
an analogy to net_cls cgroup for processes), set by user space routing
daemons or via iproute2 as an indicator for traffic classifiers and
later on processed in the eBPF program.

Unlike actions, the classifier can inspect device flags and enable
netif_keep_dst() if necessary. tc actions don't have that possibility,
but in case people know what they are doing, it can be used from there
as well (e.g. via devs that must keep dsts by design anyway).

If a realm is set, the handler returns the non-zero realm. User space
can set the full 32bit realm for the dst.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 05:02:41 -07:00
Daniel Borkmann a91263d520 ebpf: migrate bpf_prog's flags to bitfield
As we need to add further flags to the bpf_prog structure, lets migrate
both bools to a bitfield representation. The size of the base structure
(excluding insns) remains unchanged at 40 bytes.

Add also tags for the kmemchecker, so that it doesn't throw false
positives. Even in case gcc would generate suboptimal code, it's not
being accessed in performance critical paths.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 05:02:39 -07:00
Jiri Pirko 1f86839874 switchdev: rename SWITCHDEV_ATTR_* enum values to SWITCHDEV_ATTR_ID_*
To be aligned with obj.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:49:37 -07:00
Eric Dumazet ef547f2ac1 tcp: remove max_qlen_log
This control variable was set at first listen(fd, backlog)
call, but not updated if application tried to increase or decrease
backlog. It made sense at the time listener had a non resizeable
hash table.

Also rounding to powers of two was not very friendly.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:32:44 -07:00
Eric Dumazet 10cbc8f179 tcp/dccp: remove struct listen_sock
It is enough to check listener sk_state, no need for an extra
condition.

max_qlen_log can be moved into struct request_sock_queue

We can remove syn_wait_lock and the alignment it enforced.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:32:43 -07:00
Eric Dumazet 81b496b31a tcp/dccp: shrink struct listen_sock
We no longer use hash_rnd, nr_table_entries and syn_table[]

For a listener with a backlog of 10 millions sockets, this
saves 80 MBytes of vmalloced memory.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:32:42 -07:00
Eric Dumazet 079096f103 tcp/dccp: install syn_recv requests into ehash table
In this patch, we insert request sockets into TCP/DCCP
regular ehash table (where ESTABLISHED and TIMEWAIT sockets
are) instead of using the per listener hash table.

ACK packets find SYN_RECV pseudo sockets without having
to find and lock the listener.

In nominal conditions, this halves pressure on listener lock.

Note that this will allow for SO_REUSEPORT refinements,
so that we can select a listener using cpu/numa affinities instead
of the prior 'consistent hash', since only SYN packets will
apply this selection logic.

We will shrink listen_sock in the following patch to ease
code review.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Ying Cai <ycai@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:32:41 -07:00
Eric Dumazet aac065c50a tcp: move qlen/young out of struct listen_sock
qlen_inc & young_inc were protected by listener lock,
while qlen_dec & young_dec were atomic fields.

Everything needs to be atomic for upcoming lockless listener.

Also move qlen/young in request_sock_queue as we'll get rid
of struct listen_sock eventually.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:32:36 -07:00
Eric Dumazet fff1f3001c tcp: add a spinlock to protect struct request_sock_queue
struct request_sock_queue fields are currently protected
by the listener 'lock' (not a real spinlock)

We need to add a private spinlock instead, so that softirq handlers
creating children do not have to worry with backlog notion
that the listener 'lock' carries.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-03 04:32:36 -07:00
David S. Miller f6d3125fa3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/dsa/slave.c

net/dsa/slave.c simply had overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-02 07:21:25 -07:00
David Ahern 21fdd092ac net: Add support for filtering neigh dump by master device
Add support for filtering neighbor dumps by master device by adding
the NDA_MASTER attribute to the dump request. A new netlink flag,
NLM_F_DUMP_FILTERED, is added to indicate the kernel supports the
request and output is filtered as requested.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29 21:33:54 -07:00
Eric Dumazet 0536fcc039 tcp: prepare fastopen code for upcoming listener changes
While auditing TCP stack for upcoming 'lockless' listener changes,
I found I had to change fastopen_init_queue() to properly init the object
before publishing it.

Otherwise an other cpu could try to lock the spinlock before it gets
properly initialized.

Instead of adding appropriate barriers, just remove dynamic memory
allocations :
- Structure is 28 bytes on 64bit arches. Using additional 8 bytes
  for holding a pointer seems overkill.
- Two listeners can share same cache line and performance would suffer.

If we really want to save few bytes, we would instead dynamically allocate
whole struct request_sock_queue in the future.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29 16:53:10 -07:00
Pravin B Shelar 31b33dfb0a skbuff: Fix skb checksum partial check.
Earlier patch 6ae459bda tried to detect void ckecksum partial
skb by comparing pull length to checksum offset. But it does
not work for all cases since checksum-offset depends on
updates to skb->data.

Following patch fixes it by validating checksum start offset
after skb-data pointer is updated. Negative value of checksum
offset start means there is no need to checksum.

Fixes: 6ae459bda ("skbuff: Fix skb checksum flag on skb pull")
Reported-by: Andrew Vagin <avagin@odin.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29 16:48:46 -07:00
Alexander Duyck 822d54b9c2 netpoll: Drop budget parameter from NAPI polling call hierarchy
For some reason we were carrying the budget value around between the
various calls to napi->poll.  If for example one of the drivers called had
a bug in which it returned a non-zero value for work this could result in
the budget value becoming negative.

Rather than carry around a value of budget that is 0 or less we can instead
just loop through and pass 0 to each napi->poll call.  If any driver
returns a value for work done that is non-zero then we can report that
driver and continue rather than allowing a bad actor to make the budget
value negative and pass that negative value to napi->poll.

Note, the only actual change here is that instead of letting budget become
negative we are keeping it at 0 regardless of the value returned for work
since it should not be possible for the polling routine to do any actual
work with a budget of 0.  So if the polling routine returns a non-0 value
we are just reporting it and continuing with a budget of 0 rather than
letting that work value be subtracted from the budget of 0.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29 14:57:16 -07:00
Alexander Stein 75c261b51b net sysfs: Print link speed as signed integer
Otherwise 4294967295 (MBit/s) (-1) will be printed when there is no link.
Documentation/ABI/testing/sysfs-class-net does not state if this shall be
signed or unsigned.
Also remove the now unused variable fmt_udec.

Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-29 14:56:20 -07:00
David S. Miller 4963ed48f2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/ipv4/arp.c

The net/ipv4/arp.c conflict was one commit adding a new
local variable while another commit was deleting one.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-26 16:08:27 -07:00
Michal Kubeček 6ea29da1d0 net: remove unused argument of __netdev_find_adj()
The __netdev_find_adj() helper does not use its first argument, only the
device to find and list to walk through.

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-25 12:35:15 -07:00
Russell King 9861f72074 net: fix net_device refcounting
of_find_net_device_by_node() uses class_find_device() internally to
lookup the corresponding network device.  class_find_device() returns
a reference to the embedded struct device, with its refcount
incremented.

Add a comment to the definition in net/core/net-sysfs.c indicating the
need to drop this refcount, and fix the DSA code to drop this refcount
when the OF-generated platform data is cleaned up and freed.  Also
arrange for the ref to be dropped when handling errors.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-24 23:04:53 -07:00
Wilson Kok 41fc014332 fib_rules: fix fib rule dumps across multiple skbs
dump_rules returns skb length and not error.
But when family == AF_UNSPEC, the caller of dump_rules
assumes that it returns an error. Hence, when family == AF_UNSPEC,
we continue trying to dump on -EMSGSIZE errors resulting in
incorrect dump idx carried between skbs belonging to the same dump.
This results in fib rule dump always only dumping rules that fit
into the first skb.

This patch fixes dump_rules to return error so that we exit correctly
and idx is correctly maintained between skbs that are part of the
same dump.

Signed-off-by: Wilson Kok <wkok@cumulusnetworks.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-24 15:21:54 -07:00
Neil Horman 2d8bff1269 netpoll: Close race condition between poll_one_napi and napi_disable
Drivers might call napi_disable while not holding the napi instance poll_lock.
In those instances, its possible for a race condition to exist between
poll_one_napi and napi_disable.  That is to say, poll_one_napi only tests the
NAPI_STATE_SCHED bit to see if there is work to do during a poll, and as such
the following may happen:

CPU0				CPU1
ndo_tx_timeout			napi_poll_dev
 napi_disable			 poll_one_napi
  test_and_set_bit (ret 0)
				  test_bit (ret 1)
   reset adapter		   napi_poll_routine

If the adapter gets a tx timeout without a napi instance scheduled, its possible
for the adapter to think it has exclusive access to the hardware  (as the napi
instance is now scheduled via the napi_disable call), while the netpoll code
thinks there is simply work to do.  The result is parallel hardware access
leading to corrupt data structures in the driver, and a crash.

Additionaly, there is another, more critical race between netpoll and
napi_disable.  The disabled napi state is actually identical to the scheduled
state for a given napi instance.  The implication being that, if a napi instance
is disabled, a netconsole instance would see the napi state of the device as
having been scheduled, and poll it, likely while the driver was dong something
requiring exclusive access.  In the case above, its fairly clear that not having
the rings in a state ready to be polled will cause any number of crashes.

The fix should be pretty easy.  netpoll uses its own bit to indicate that that
the napi instance is in a state of being serviced by netpoll (NAPI_STATE_NPSVC).
We can just gate disabling on that bit as well as the sched bit.  That should
prevent netpoll from conducting a napi poll if we convert its set bit to a
test_and_set_bit operation to provide mutual exclusion

Change notes:
V2)
	Remove a trailing whtiespace
	Resubmit with proper subject prefix

V3)
	Clean up spacing nits

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: jmaxwell@redhat.com
Tested-by: jmaxwell@redhat.com
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-23 14:32:50 -07:00
Daniel Borkmann 927ab1d764 sched, bpf: let stack handle !IFF_UP devs on bpf_clone_redirect
Similarly as already the case in bpf_redirect()/skb_do_redirect()
pair, let the stack deal with devs that are !IFF_UP.

dev_forward_skb() as well as dev_queue_xmit() will free the skb
and increment drop counter internally in such cases, so we can
spare the condition in bpf_clone_redirect().

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-23 14:25:51 -07:00
Alexei Starovoitov 27b29f6305 bpf: add bpf_redirect() helper
Existing bpf_clone_redirect() helper clones skb before redirecting
it to RX or TX of destination netdev.
Introduce bpf_redirect() helper that does that without cloning.

Benchmarked with two hosts using 10G ixgbe NICs.
One host is doing line rate pktgen.
Another host is configured as:
$ tc qdisc add dev $dev ingress
$ tc filter add dev $dev root pref 10 u32 match u32 0 0 flowid 1:2 \
   action bpf run object-file tcbpf1_kern.o section clone_redirect_xmit drop
so it receives the packet on $dev and immediately xmits it on $dev + 1
The section 'clone_redirect_xmit' in tcbpf1_kern.o file has the program
that does bpf_clone_redirect() and performance is 2.0 Mpps

$ tc filter add dev $dev root pref 10 u32 match u32 0 0 flowid 1:2 \
   action bpf run object-file tcbpf1_kern.o section redirect_xmit drop
which is using bpf_redirect() - 2.4 Mpps

and using cls_bpf with integrated actions as:
$ tc filter add dev $dev root pref 10 \
  bpf run object-file tcbpf1_kern.o section redirect_xmit integ_act classid 1
performance is 2.5 Mpps

To summarize:
u32+act_bpf using clone_redirect - 2.0 Mpps
u32+act_bpf using redirect - 2.4 Mpps
cls_bpf using redirect - 2.5 Mpps

For comparison linux bridge in this setup is doing 2.1 Mpps
and ixgbe rx + drop in ip_rcv - 7.8 Mpps

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 21:09:07 -07:00
Daniel Borkmann 045efa82ff cls_bpf: introduce integrated actions
Often cls_bpf classifier is used with single action drop attached.
Optimize this use case and let cls_bpf return both classid and action.
For backwards compatibility reasons enable this feature under
TCA_BPF_FLAG_ACT_DIRECT flag.

Then more interesting programs like the following are easier to write:
int cls_bpf_prog(struct __sk_buff *skb)
{
  /* classify arp, ip, ipv6 into different traffic classes
   * and drop all other packets
   */
  switch (skb->protocol) {
  case htons(ETH_P_ARP):
    skb->tc_classid = 1;
    break;
  case htons(ETH_P_IP):
    skb->tc_classid = 2;
    break;
  case htons(ETH_P_IPV6):
    skb->tc_classid = 3;
    break;
  default:
    return TC_ACT_SHOT;
  }

  return TC_ACT_OK;
}

Joint work with Daniel Borkmann.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 21:09:06 -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 04eb44890e bridge: Add br_netif_receive_skb remove netif_receive_skb_sk
netif_receive_skb_sk is only called once in the bridge code, replace
it with a bridge specific function that calls netif_receive_skb.

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 2b4aa3cec4 net: Remove dev_queue_xmit_sk
A function with weird arguments that it will never use to accomdate a
netfilter callback prototype is absolutely in the core of the
networking stack.  Frankly it does not make sense and it causes a lot
of confusion as to why arguments that are never used are being passed
to the function.

As I am preparing to make a second change to arguments to the okfn even
the names stops making sense.

As I have removed the two callers of this function remove this confusion
from the networking stack.

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
Thadeu Lima de Souza Cascardo c4047f533f net-sysfs: get_netdev_queue_index() cleanup
Redo commit ed1acc8cd8.

Commit 822b3b2ebf ("net: Add max rate tx queue
attribute") moved get_netdev_queue_index around, but kept the old version.
Probably because of a reuse of the original patch from before Eric's change to
that function.

Remove one inline keyword, and no need for a loop to find
an index into a table.

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@redhat.com>
Fixes: 822b3b2ebf ("net: Add max rate tx queue attribute")
Acked-by:  Or Gerlitz <ogerlitz@mellanox.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-17 16:35:15 -07:00
Julia Lawall adf78edac0 net: core: drop null test before destroy functions
Remove unneeded NULL test.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@ expression x; @@
-if (x != NULL) {
  \(kmem_cache_destroy\|mempool_destroy\|dma_pool_destroy\)(x);
  x = NULL;
-}
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-15 16:49:43 -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
Roopa Prabhu d64f69b037 rtnetlink: catch -EOPNOTSUPP errors from ndo_bridge_getlink
problem reported:
	kernel 4.1.3
	------------
	# bridge vlan
	port	vlan ids
	eth0	 1 PVID Egress Untagged
	 	90
	 	91
	 	92
	 	93
	 	94
	 	95
	 	96
	 	97
	 	98
	 	99
	 	100

	vmbr0	 1 PVID Egress Untagged
	 	94

	kernel 4.2
	-----------
	# bridge vlan
	port	vlan ids

ndo_bridge_getlink can return -EOPNOTSUPP when an interfaces
ndo_bridge_getlink op is set to switchdev_port_bridge_getlink
and CONFIG_SWITCHDEV is not defined. This today can happen to
bond, rocker and team devices. This patch adds -EOPNOTSUPP
checks after calls to ndo_bridge_getlink.

Fixes: 85fdb95672 ("switchdev: cut over to new switchdev_port_bridge_getlink")
Reported-by: Alexandre DERUMIER <aderumier@odiso.com>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-15 15:03:57 -07:00
Tycho Andersen 19539ce783 ebpf: emit correct src_reg for conditional jumps
Instead of always emitting BPF_REG_X, let's emit BPF_REG_X only when the
source actually is BPF_X. This causes programs generated by the classic
converter to not be importable via bpf(), as the eBPF verifier checks that
the src_reg is correct or 0. While not a problem yet, this will be a
problem when BPF_PROG_DUMP lands, and we can potentially dump and re-import
programs generated by the converter.

Signed-off-by: Tycho Andersen <tycho.andersen@canonical.com>
CC: Alexei Starovoitov <ast@kernel.org>
CC: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-11 14:52:41 -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 b382c08656 sock, diag: fix panic in sock_diag_put_filterinfo
diag socket's sock_diag_put_filterinfo() dumps classic BPF programs
upon request to user space (ss -0 -b). However, native eBPF programs
attached to sockets (SO_ATTACH_BPF) cannot be dumped with this method:

Their orig_prog is always NULL. However, sock_diag_put_filterinfo()
unconditionally tries to access its filter length resp. wants to copy
the filter insns from there. Internal cBPF to eBPF transformations
attached to sockets don't have this issue, as orig_prog state is kept.

It's currently only used by packet sockets. If we would want to add
native eBPF support in the future, this needs to be done through
a different attribute than PACKET_DIAG_FILTER to not confuse possible
user space disassemblers that work on diag data.

Fixes: 89aa075832 ("net: sock: allow eBPF programs to be attached to sockets")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-02 11:29:29 -07:00
David S. Miller 20a17bf6c0 flow_dissector: Use 'const' where possible.
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 21:19:17 -07:00
David S. Miller a17ace95b0 flow: Move __get_hash_from_flowi{4,6} into flow_dissector.c
These cannot live in net/core/flow.c which only builds when XFRM is
enabled.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 17:00:24 -07:00
David S. Miller 4b36993d3d flow_dissector: Don't use bit fields.
Just have a flags member instead.

   In file included from include/linux/linkage.h:4:0,
                    from include/linux/kernel.h:6,
                    from net/core/flow_dissector.c:1:
   In function 'flow_keys_hash_start',
       inlined from 'flow_hash_from_keys' at net/core/flow_dissector.c:553:34:
>> include/linux/compiler.h:447:38: error: call to '__compiletime_assert_459' declared with attribute error: BUILD_BUG_ON failed: FLOW_KEYS_HASH_OFFSET % sizeof(u32)

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 16:46:08 -07:00
Tom Herbert 6db61d79c1 flow_dissector: Ignore flow dissector return value from ___skb_get_hash
In ___skb_get_hash ignore return value from skb_flow_dissect_flow_keys.
A failure in that function likely means that there was a parse error,
so we may as well use whatever fields were found before the error was
hit.  This is also good because it means we won't keep trying to derive
the hash on subsequent calls to skb_get_hash for the same packet.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:23 -07:00
Tom Herbert 823b969395 flow_dissector: Add control/reporting of encapsulation
Add an input flag to flow dissector on rather dissection should stop
when encapsulation is detected (IP/IP or GRE). Also, add a key_control
flag that indicates encapsulation was encountered during the
dissection.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:23 -07:00
Tom Herbert 872b1abb1e flow_dissector: Add flag to stop parsing when an IPv6 flow label is seen
Add an input flag to flow dissector on rather dissection should be
stopped when a flow label is encountered. Presumably, the flow label
is derived from a sufficient hash of an inner transport packet so
further dissection is not needed (that is ports are not included in
the flow hash). Using the flow label instead of ports has the additional
benefit that packet fragments should hash to same value as non-fragments
for a flow (assuming that the same flow label is used).

We set this flag by default in for skb_get_hash.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:23 -07:00
Tom Herbert 8306b688f1 flow_dissector: Add flag to stop parsing at L3
Add an input flag to flow dissector on rather dissection should be
stopped when an L3 packet is encountered. This would be useful if a
caller just wanted to get IP addresses of the outermost header (e.g.
to do an L3 hash).

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:23 -07:00
Tom Herbert b840f28b90 flow_dissector: Support IPv6 fragment header
Parse NEXTHDR_FRAGMENT. When seen account for it in the fragment bits of
key_control. Also, check if first fragment should be parsed.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:22 -07:00
Tom Herbert 807e165dc4 flow_dissector: Add control/reporting of fragmentation
Add an input flag to flow dissector on rather dissection should be
attempted on a first fragment. Also add key_control flags to indicate
that a packet is a fragment or first fragment.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:22 -07:00
Tom Herbert cd79a2382a flow_dissector: Add flags argument to skb_flow_dissector functions
The flags argument will allow control of the dissection process (for
instance whether to parse beyond L3).

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:22 -07:00
Tom Herbert a6e544b0a8 flow_dissector: Jump to exit code in __skb_flow_dissect
Instead of returning immediately (on a parsing failure for instance) we
jump to cleanup code. This always sets protocol values in key_control
(even on a failure there is still valid information in the key_tags that
was set before the problem was hit).

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:22 -07:00
Tom Herbert c6cc1ca7f4 flowi: Abstract out functions to get flow hash based on flowi
Create __get_hash_from_flowi6 and __get_hash_from_flowi4 to get the
flow keys and hash based on flowi structures. These are called by
__skb_get_hash_flowi6 and __skb_get_hash_flowi4. Also, created
get_hash_from_flowi6 and get_hash_from_flowi4 which can be called
when just the hash value for a flowi is needed.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:22 -07:00
Tom Herbert bcc83839ff skbuff: Make __skb_set_sw_hash a general function
Move __skb_set_sw_hash to skbuff.h and add __skb_set_hash which is
a common method (between __skb_set_sw_hash and skb_set_hash) to set
the hash in an skbuff.

Also, move skb_clear_hash to be closer to __skb_set_hash.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-09-01 15:06:22 -07:00
Pravin B Shelar 63b6c13dbb tun_dst: Remove opts_size
opts_size is only written and never read. Following patch
removes this unused variable.

Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-31 21:23:42 -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
Jiri Benc 7f9562a1f4 ip_tunnels: record IP version in tunnel info
There's currently nothing preventing directing packets with IPv6
encapsulation data to IPv4 tunnels (and vice versa). If this happens,
IPv6 addresses are incorrectly interpreted as IPv4 ones.

Track whether the given ip_tunnel_key contains IPv4 or IPv6 data. Store this
in ip_tunnel_info. Reject packets at appropriate places if they are supposed
to be encapsulated into an incompatible protocol.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-29 13:07:54 -07:00
David Ahern f6d3c19274 net: FIB tracepoints
A few useful tracepoints developing VRF driver.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-29 13:05:16 -07:00
Nikolay Aleksandrov c9fd56b34e netpoll: warn on netpoll_send_udp users who haven't disabled irqs
Make sure we catch future netpoll_send_udp users who use it without
disabling irqs and also as a hint for poll_controller users.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-28 16:24:54 -07:00
David S. Miller 0d36938bb8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-08-27 21:45:31 -07:00
Phil Sutter f84bb1eac0 net: fix IFF_NO_QUEUE for drivers using alloc_netdev
Printing a warning in alloc_netdev_mqs() if tx_queue_len is zero and
IFF_NO_QUEUE not set is not appropriate since drivers may use one of the
alloc_netdev* macros instead of alloc_etherdev*, thereby not
intentionally leaving tx_queue_len uninitialized. Instead check here if
tx_queue_len is zero and set IFF_NO_QUEUE, so the value of tx_queue_len
can be ignored in net/sched_generic.c.

Fixes: 906470c ("net: warn if drivers set tx_queue_len = 0")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-27 17:14:29 -07:00
Jean Sacren 69dba9bbc5 sock: fix kernel doc error
The symbol '__sk_reclaim' is not present in the current tree. Apparently
'__sk_reclaim' was meant to be '__sk_mem_reclaim', so fix it with the
right symbol name for the kernel doc.

Signed-off-by: Jean Sacren <sakiwit@gmail.com>
Cc: Hideo Aoki <haoki@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-27 17:12:41 -07:00
Jiri Pirko 0e4ead9d7b net: introduce change upper device notifier change info
Add info that is passed along with NETDEV_CHANGEUPPER event.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-27 16:28:34 -07:00
Daniel Borkmann 3b3ae88026 net: sched: consolidate tc_classify{,_compat}
For classifiers getting invoked via tc_classify(), we always need an
extra function call into tc_classify_compat(), as both are being
exported as symbols and tc_classify() itself doesn't do much except
handling of reclassifications when tp->classify() returned with
TC_ACT_RECLASSIFY.

CBQ and ATM are the only qdiscs that directly call into tc_classify_compat(),
all others use tc_classify(). When tc actions are being configured
out in the kernel, tc_classify() effectively does nothing besides
delegating.

We could spare this layer and consolidate both functions. pktgen on
single CPU constantly pushing skbs directly into the netif_receive_skb()
path with a dummy classifier on ingress qdisc attached, improves
slightly from 22.3Mpps to 23.1Mpps.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-27 14:18:48 -07:00
Alexei Starovoitov 1dd34b5ad8 bpf: fix bpf_skb_set_tunnel_key() helper
Make sure to indicate to tunnel driver that key.tun_id is set,
otherwise gre won't recognize the metadata.

Fixes: d3aa45ce6b ("bpf: add helpers to access tunnel metadata")
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-26 17:38:13 -07:00
WANG Cong e252b3d1a1 route: fix a use-after-free
This patch fixes the following crash:

 general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC
 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.2.0-rc7+ #166
 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
 task: ffff88010656d280 ti: ffff880106570000 task.ti: ffff880106570000
 RIP: 0010:[<ffffffff8182f91b>]  [<ffffffff8182f91b>] dst_destroy+0xa6/0xef
 RSP: 0018:ffff880107603e38  EFLAGS: 00010202
 RAX: 0000000000000001 RBX: ffff8800d225a000 RCX: ffffffff82250fd0
 RDX: 0000000000000001 RSI: ffffffff82250fd0 RDI: 6b6b6b6b6b6b6b6b
 RBP: ffff880107603e58 R08: 0000000000000001 R09: 0000000000000001
 R10: 000000000000b530 R11: ffff880107609000 R12: 0000000000000000
 R13: ffffffff82343c40 R14: 0000000000000000 R15: ffffffff8182fb4f
 FS:  0000000000000000(0000) GS:ffff880107600000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
 CR2: 00007fcabd9d3000 CR3: 00000000d7279000 CR4: 00000000000006e0
 Stack:
  ffffffff82250fd0 ffff8801077d6f00 ffffffff82253c40 ffff8800d225a000
  ffff880107603e68 ffffffff8182fb5d ffff880107603f08 ffffffff810d795e
  ffffffff810d7648 ffff880106574000 ffff88010656d280 ffff88010656d280
 Call Trace:
  <IRQ>
  [<ffffffff8182fb5d>] dst_destroy_rcu+0xe/0x1d
  [<ffffffff810d795e>] rcu_process_callbacks+0x618/0x7eb
  [<ffffffff810d7648>] ? rcu_process_callbacks+0x302/0x7eb
  [<ffffffff8182fb4f>] ? dst_gc_task+0x1eb/0x1eb
  [<ffffffff8107e11b>] __do_softirq+0x178/0x39f
  [<ffffffff8107e52e>] irq_exit+0x41/0x95
  [<ffffffff81a4f215>] smp_apic_timer_interrupt+0x34/0x40
  [<ffffffff81a4d5cd>] apic_timer_interrupt+0x6d/0x80
  <EOI>
  [<ffffffff8100b968>] ? default_idle+0x21/0x32
  [<ffffffff8100b966>] ? default_idle+0x1f/0x32
  [<ffffffff8100bf19>] arch_cpu_idle+0xf/0x11
  [<ffffffff810b0bc7>] default_idle_call+0x1f/0x21
  [<ffffffff810b0dce>] cpu_startup_entry+0x1ad/0x273
  [<ffffffff8102fe67>] start_secondary+0x135/0x156

dst is freed right before lwtstate_put(), this is not correct...

Fixes: 61adedf3e3 ("route: move lwtunnel state to dst_entry")
Acked-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-25 14:29:19 -07:00
Masanari Iida d749916010 net-next: Fix warning while make xmldocs caused by skbuff.c
This patch fix following warnings.

.//net/core/skbuff.c:407: warning: No description found
for parameter 'len'
.//net/core/skbuff.c:407: warning: Excess function parameter
 'length' description in '__netdev_alloc_skb'
.//net/core/skbuff.c:476: warning: No description found
 for parameter 'len'
.//net/core/skbuff.c:476: warning: Excess function parameter
'length' description in '__napi_alloc_skb'

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-25 14:20:48 -07:00
Tom Herbert 127eb7cd3c lwt: Add cfg argument to build_state
Add cfg and family arguments to lwt build state functions. cfg is a void
pointer and will either be a pointer to a fib_config or fib6_config
structure. The family parameter indicates which one (either AF_INET
or AF_INET6).

LWT encpasulation implementation may use the fib configuration to build
the LWT state.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-24 10:34:40 -07:00
Michal Hocko 2f064f3485 mm: make page pfmemalloc check more robust
Commit c48a11c7ad ("netvm: propagate page->pfmemalloc to skb") added
checks for page->pfmemalloc to __skb_fill_page_desc():

        if (page->pfmemalloc && !page->mapping)
                skb->pfmemalloc = true;

It assumes page->mapping == NULL implies that page->pfmemalloc can be
trusted.  However, __delete_from_page_cache() can set set page->mapping
to NULL and leave page->index value alone.  Due to being in union, a
non-zero page->index will be interpreted as true page->pfmemalloc.

So the assumption is invalid if the networking code can see such a page.
And it seems it can.  We have encountered this with a NFS over loopback
setup when such a page is attached to a new skbuf.  There is no copying
going on in this case so the page confuses __skb_fill_page_desc which
interprets the index as pfmemalloc flag and the network stack drops
packets that have been allocated using the reserves unless they are to
be queued on sockets handling the swapping which is the case here and
that leads to hangs when the nfs client waits for a response from the
server which has been dropped and thus never arrive.

The struct page is already heavily packed so rather than finding another
hole to put it in, let's do a trick instead.  We can reuse the index
again but define it to an impossible value (-1UL).  This is the page
index so it should never see the value that large.  Replace all direct
users of page->pfmemalloc by page_is_pfmemalloc which will hide this
nastiness from unspoiled eyes.

The information will get lost if somebody wants to use page->index
obviously but that was the case before and the original code expected
that the information should be persisted somewhere else if that is
really needed (e.g.  what SLAB and SLUB do).

[akpm@linux-foundation.org: fix blooper in slub]
Fixes: c48a11c7ad ("netvm: propagate page->pfmemalloc to skb")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Debugged-by: Vlastimil Babka <vbabka@suse.com>
Debugged-by: Jiri Bohac <jbohac@suse.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David Miller <davem@davemloft.net>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: <stable@vger.kernel.org>	[3.6+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-21 14:30:10 -07:00
David S. Miller dc25b25897 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/usb/qmi_wwan.c

Overlapping additions of new device IDs to qmi_wwan.c

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-21 11:44:04 -07:00
Jiri Benc 61adedf3e3 route: move lwtunnel state to dst_entry
Currently, the lwtunnel state resides in per-protocol data. This is
a problem if we encapsulate ipv6 traffic in an ipv4 tunnel (or vice versa).
The xmit function of the tunnel does not know whether the packet has been
routed to it by ipv4 or ipv6, yet it needs the lwtstate data. Moving the
lwtstate data to dst_entry makes such inter-protocol tunneling possible.

As a bonus, this brings a nice diffstat.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-20 15:42:36 -07:00
Jiri Benc c1ea5d672a ip_tunnels: add IPv6 addresses to ip_tunnel_key
Add the IPv6 addresses as an union with IPv4 ones. When using IPv4, the
newly introduced padding after the IPv4 addresses needs to be zeroed out.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-20 15:42:36 -07:00
Phil Sutter 906470c19d net: warn if drivers set tx_queue_len = 0
Due to the introduction of IFF_NO_QUEUE, there is a better way for
drivers to indicate that no qdisc should be attached by default. Though,
the old convention can't be dropped since ignoring that setting would
break drivers still using it. Instead, add a warning so out-of-tree
driver maintainers get a chance to adjust their code before we finally
get rid of any special handling of tx_queue_len == 0.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-18 11:55:08 -07:00
Tom Herbert abc5d1ff3e net: Add inet_proto_csum_replace_by_diff utility function
This function updates a checksum field value and skb->csum based on
a value which is the difference between the old and new checksum.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-17 21:33:06 -07:00
Tom Herbert 4b048d6d9d net: Change pseudohdr argument of inet_proto_csum_replace* to be a bool
inet_proto_csum_replace4,2,16 take a pseudohdr argument which indicates
the checksum field carries a pseudo header. This argument should be a
boolean instead of an int.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-17 21:33:06 -07:00
Tom Herbert 2536862311 lwt: Add support to redirect dst.input
This patch adds the capability to redirect dst input in the same way
that dst output is redirected by LWT.

Also, save the original dst.input and and dst.out when setting up
lwtunnel redirection. These can be called by the client as a pass-
through.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-17 21:33:05 -07:00
David S. Miller 2ea273d76a net: Export bpf_prog_create_from_user().
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-17 14:37:06 -07:00
Sasha Levin da65ad1fe3 net: allow sleeping when modifying store_rps_map
Commit 10e4ea751 ("net: Fix race condition in store_rps_map") has moved the
manipulation of the rps_needed jump label under a spinlock. Since changing
the state of a jump label may sleep this is incorrect and causes warnings
during runtime.

Make rps_map_lock a mutex to allow sleeping under it.

Fixes: 10e4ea751 ("net: Fix race condition in store_rps_map")
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-13 21:40:57 -07:00
Linus Lüssing a516993f0a net: fix wrong skb_get() usage / crash in IGMP/MLD parsing code
The recent refactoring of the IGMP and MLD parsing code into
ipv6_mc_check_mld() / ip_mc_check_igmp() introduced a potential crash /
BUG() invocation for bridges:

I wrongly assumed that skb_get() could be used as a simple reference
counter for an skb which is not the case. skb_get() bears additional
semantics, a user count. This leads to a BUG() invocation in
pskb_expand_head() / kernel panic if pskb_may_pull() is called on an skb
with a user count greater than one - unfortunately the refactoring did
just that.

Fixing this by removing the skb_get() call and changing the API: The
caller of ipv6_mc_check_mld() / ip_mc_check_igmp() now needs to
additionally check whether the returned skb_trimmed is a clone.

Fixes: 9afd85c9e4 ("net: Export IGMP/MLD message validation code")
Reported-by: Brenden Blanco <bblanco@plumgrid.com>
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-13 17:08:39 -07:00
David S. Miller 182ad468e7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/cavium/Kconfig

The cavium conflict was overlapping dependency
changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-13 16:23:11 -07:00
Eric Dumazet 2235f2ac75 inet: fix races with reqsk timers
reqsk_queue_destroy() and reqsk_queue_unlink() should use
del_timer_sync() instead of del_timer() before calling reqsk_put(),
otherwise we could free a req still used by another cpu.

But before doing so, reqsk_queue_destroy() must release syn_wait_lock
spinlock or risk a dead lock, as reqsk_timer_handler() might
need to take this same spinlock from reqsk_queue_unlink() (called from
inet_csk_reqsk_queue_drop())

Fixes: fa76ce7328 ("inet: get rid of central tcp/dccp listener timer")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-10 21:17:29 -07:00
Rick Jones fb811395cd net: add explicit logging and stat for neighbour table overflow
Add an explicit neighbour table overflow message (ratelimited) and
statistic to make diagnosing neighbour table overflows tractable in
the wild.

Diagnosing a neighbour table overflow can be quite difficult in the wild
because there is no explicit dmesg logged.  Callers to neighbour code
seem to use net_dbg_ratelimit when the neighbour call fails which means
the "base message" is not emitted and the callback suppressed messages
from the ratelimiting can end-up juxtaposed with unrelated messages.
Further, a forced garbage collection will increment a stat on each call
whether it was successful in freeing-up a table entry or not, so that
statistic is only a hint.  So, add a net_info_ratelimited message and
explicit statistic to the neighbour code.

Signed-off-by: Rick Jones <rick.jones2@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-10 13:46:21 -07:00
Tom Herbert 10e4ea7514 net: Fix race condition in store_rps_map
There is a race condition in store_rps_map that allows jump label
count in rps_needed to go below zero. This can happen when
concurrently attempting to set and a clear map.

Scenario:

1. rps_needed count is zero
2. New map is assigned by setting thread, but rps_needed count _not_ yet
   incremented (rps_needed count still zero)
2. Map is cleared by second thread, old_map set to that just assigned
3. Second thread performs static_key_slow_dec, rps_needed count now goes
   negative

Fix is to increment or decrement rps_needed under the spinlock.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-07 15:56:56 -07:00
Oleg Nesterov 7ba8bd75dd net: pktgen: don't abuse current->state in pktgen_thread_worker()
Commit 1fbe4b46ca "net: pktgen: kill the Wait for kthread_stop
code in pktgen_thread_worker()" removed (in particular) the final
__set_current_state(TASK_RUNNING) and I didn't notice the previous
set_current_state(TASK_INTERRUPTIBLE). This triggers the warning
in __might_sleep() after return.

Afaics, we can simply remove both set_current_state()'s, and we
could do this a long ago right after ef87979c27 "pktgen: better
scheduler friendliness" which changed pktgen_thread_worker() to
use wait_event_interruptible_timeout().

Reported-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-06 23:52:44 -07:00
Herbert Xu a0a2a66024 net: Fix skb_set_peeked use-after-free bug
The commit 738ac1ebb9 ("net: Clone
skb before setting peeked flag") introduced a use-after-free bug
in skb_recv_datagram.  This is because skb_set_peeked may create
a new skb and free the existing one.  As it stands the caller will
continue to use the old freed skb.

This patch fixes it by making skb_set_peeked return the new skb
(or the old one if unchanged).

Fixes: 738ac1ebb9 ("net: Clone skb before setting peeked flag")
Reported-by: Brenden Blanco <bblanco@plumgrid.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Brenden Blanco <bblanco@plumgrid.com>
Reviewed-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-06 21:55:47 -07:00
Robert Shearman abf7c1c540 lwtunnel: set skb protocol and dev
In the locally-generated packet path skb->protocol may not be set and
this is required for the lwtunnel encap in order to get the lwtstate.

This would otherwise have been set by ip_output or ip6_output so set
skb->protocol prior to calling the lwtunnel encap
function. Additionally set skb->dev in case it is needed further down
the transmit path.

Signed-off-by: Robert Shearman <rshearma@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-03 22:26:13 -07:00
Daniel Borkmann ba7591d8b2 ebpf: add skb->hash to offset map for usage in {cls, act}_bpf or filters
Add skb->hash to the __sk_buff offset map, so it can be accessed from
an eBPF program. We currently already do this for classic BPF filters,
but not yet on eBPF, it might be useful as a demuxer in combination with
helpers like bpf_clone_redirect(), toy example:

  __section("cls-lb") int ingress_main(struct __sk_buff *skb)
  {
    unsigned int which = 3 + (skb->hash & 7);
    /* bpf_skb_store_bytes(skb, ...); */
    /* bpf_l{3,4}_csum_replace(skb, ...); */
    bpf_clone_redirect(skb, which, 0);
    return -1;
  }

I was thinking whether to add skb_get_hash(), but then concluded the
raw skb->hash seems fine in this case: we can directly access the hash
w/o extra eBPF helper function call, it's filled out by many NICs on
ingress, and in case the entropy level would not be sufficient, people
can still implement their own specific sw fallback hash mix anyway.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-08-02 17:20:47 -07:00
David S. Miller 5510b3c2a1 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	arch/s390/net/bpf_jit_comp.c
	drivers/net/ethernet/ti/netcp_ethss.c
	net/bridge/br_multicast.c
	net/ipv4/ip_fragment.c

All four conflicts were cases of simple overlapping
changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31 23:52:20 -07:00
Tom Herbert f70ea018da net: Add functions to get skb->hash based on flow structures
Add skb_get_hash_flowi6 and skb_get_hash_flowi4 which derive an sk_buff
hash from flowi6 and flowi4 structures respectively. These functions
can be called when creating a packet in the output path where the new
sk_buff does not yet contain a fully formed packet that is parsable by
flow dissector.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31 17:07:11 -07:00
Alexei Starovoitov d3aa45ce6b bpf: add helpers to access tunnel metadata
Introduce helpers to let eBPF programs attached to TC manipulate tunnel metadata:
bpf_skb_[gs]et_tunnel_key(skb, key, size, flags)
skb: pointer to skb
key: pointer to 'struct bpf_tunnel_key'
size: size of 'struct bpf_tunnel_key'
flags: room for future extensions

First eBPF program that uses these helpers will allocate per_cpu
metadata_dst structures that will be used on TX.
On RX metadata_dst is allocated by tunnel driver.

Typical usage for TX:
struct bpf_tunnel_key tkey;
... populate tkey ...
bpf_skb_set_tunnel_key(skb, &tkey, sizeof(tkey), 0);
bpf_clone_redirect(skb, vxlan_dev_ifindex, 0);

RX:
struct bpf_tunnel_key tkey = {};
bpf_skb_get_tunnel_key(skb, &tkey, sizeof(tkey), 0);
... lookup or redirect based on tkey ...

'struct bpf_tunnel_key' will be extended in the future by adding
elements to the end and the 'size' argument will indicate which fields
are populated, thereby keeping backwards compatibility.
The 'flags' argument may be used as well when the 'size' is not enough or
to indicate completely different layout of bpf_tunnel_key.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-31 15:20:22 -07:00
Sowmini Varadhan 8a68173691 net: sk_clone_lock() should only do get_net() if the parent is not a kernel socket
The newsk returned by sk_clone_lock should hold a get_net()
reference if, and only if, the parent is not a kernel socket
(making this similar to sk_alloc()).

E.g,. for the SYN_RECV path, tcp_v4_syn_recv_sock->..inet_csk_clone_lock
sets up the syn_recv newsk from sk_clone_lock. When the parent (listen)
socket is a kernel socket (defined in sk_alloc() as having
sk_net_refcnt == 0), then the newsk should also have a 0 sk_net_refcnt
and should not hold a get_net() reference.

Fixes: 26abe14379 ("net: Modify sk_alloc to not reference count the
      netns of kernel sockets.")
Acked-by: Eric Dumazet <edumazet@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-30 15:59:12 -07:00
Bogdan Hamciuc 1ce4b2f44d net: pktgen: Remove unused 'allocated_skbs' field
Field pktgen_dev.allocated_skbs had been written to, but never read
from. The number of allocated skbs can be deduced anyway, from the total
number of sent packets and the 'clone_skb' param.

Signed-off-by: Bogdan Hamciuc <bogdan.hamciuc@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 23:00:39 -07:00
Bogdan Hamciuc 879c7220e8 net: pktgen: Observe needed_headroom of the device
Allocate enough space so as not to force the outgoing net device to do
skb_realloc_headroom().

Signed-off-by: Bogdan Hamciuc <bogdan.hamciuc@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 23:00:39 -07:00
Thomas Graf 92a99bf3ba lwtunnel: Make lwtun_encaps[] static
Any external user should use the registration API instead of
accessing this directly.

Cc: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 22:59:39 -07:00
Dan Carpenter e11f40b935 lwtunnel: use kfree_skb() instead of vanilla kfree()
kfree_skb() is correct here.

Fixes: ffce41962e ('lwtunnel: support dst output redirect function')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27 01:24:59 -07:00
Sabrina Dubroca dfbafc9953 tcp: fix recv with flags MSG_WAITALL | MSG_PEEK
Currently, tcp_recvmsg enters a busy loop in sk_wait_data if called
with flags = MSG_WAITALL | MSG_PEEK.

sk_wait_data waits for sk_receive_queue not empty, but in this case,
the receive queue is not empty, but does not contain any skb that we
can use.

Add a "last skb seen on receive queue" argument to sk_wait_data, so
that it sleeps until the receive queue has new skbs.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=99461
Link: https://sourceware.org/bugzilla/show_bug.cgi?id=18493
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1205258
Reported-by: Enrico Scholz <rh-bugzilla@ensc.de>
Reported-by: Dan Searle <dan@censornet.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27 01:06:53 -07:00
subashab@codeaurora.org b469139e81 dev: Spelling fix in comments
Fix the following typo
- unchainged -> unchanged

Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27 00:54:57 -07:00
Konstantin Khlebnikov cc9f4daa63 cgroup: net_cls: fix false-positive "suspicious RCU usage"
In dev_queue_xmit() net_cls protected with rcu-bh.

[  270.730026] ===============================
[  270.730029] [ INFO: suspicious RCU usage. ]
[  270.730033] 4.2.0-rc3+ #2 Not tainted
[  270.730036] -------------------------------
[  270.730040] include/linux/cgroup.h:353 suspicious rcu_dereference_check() usage!
[  270.730041] other info that might help us debug this:
[  270.730043] rcu_scheduler_active = 1, debug_locks = 1
[  270.730045] 2 locks held by dhclient/748:
[  270.730046]  #0:  (rcu_read_lock_bh){......}, at: [<ffffffff81682b70>] __dev_queue_xmit+0x50/0x960
[  270.730085]  #1:  (&qdisc_tx_lock){+.....}, at: [<ffffffff81682d60>] __dev_queue_xmit+0x240/0x960
[  270.730090] stack backtrace:
[  270.730096] CPU: 0 PID: 748 Comm: dhclient Not tainted 4.2.0-rc3+ #2
[  270.730098] Hardware name: OpenStack Foundation OpenStack Nova, BIOS Bochs 01/01/2011
[  270.730100]  0000000000000001 ffff8800bafeba58 ffffffff817ad487 0000000000000007
[  270.730103]  ffff880232a0a780 ffff8800bafeba88 ffffffff810ca4f2 ffff88022fb23e00
[  270.730105]  ffff880232a0a780 ffff8800bafebb68 ffff8800bafebb68 ffff8800bafebaa8
[  270.730108] Call Trace:
[  270.730121]  [<ffffffff817ad487>] dump_stack+0x4c/0x65
[  270.730148]  [<ffffffff810ca4f2>] lockdep_rcu_suspicious+0xe2/0x120
[  270.730153]  [<ffffffff816a62d2>] task_cls_state+0x92/0xa0
[  270.730158]  [<ffffffffa00b534f>] cls_cgroup_classify+0x4f/0x120 [cls_cgroup]
[  270.730164]  [<ffffffff816aac74>] tc_classify_compat+0x74/0xc0
[  270.730166]  [<ffffffff816ab573>] tc_classify+0x33/0x90
[  270.730170]  [<ffffffffa00bcb0a>] htb_enqueue+0xaa/0x4a0 [sch_htb]
[  270.730172]  [<ffffffff81682e26>] __dev_queue_xmit+0x306/0x960
[  270.730174]  [<ffffffff81682b70>] ? __dev_queue_xmit+0x50/0x960
[  270.730176]  [<ffffffff816834a3>] dev_queue_xmit_sk+0x13/0x20
[  270.730185]  [<ffffffff81787770>] dev_queue_xmit+0x10/0x20
[  270.730187]  [<ffffffff8178b91c>] packet_snd.isra.62+0x54c/0x760
[  270.730190]  [<ffffffff8178be25>] packet_sendmsg+0x2f5/0x3f0
[  270.730203]  [<ffffffff81665245>] ? sock_def_readable+0x5/0x190
[  270.730210]  [<ffffffff817b64bb>] ? _raw_spin_unlock+0x2b/0x40
[  270.730216]  [<ffffffff8173bcbc>] ? unix_dgram_sendmsg+0x5cc/0x640
[  270.730219]  [<ffffffff8165f367>] sock_sendmsg+0x47/0x50
[  270.730221]  [<ffffffff8165f42f>] sock_write_iter+0x7f/0xd0
[  270.730232]  [<ffffffff811fd4c7>] __vfs_write+0xa7/0xf0
[  270.730234]  [<ffffffff811fe5b8>] vfs_write+0xb8/0x190
[  270.730236]  [<ffffffff811fe8c2>] SyS_write+0x52/0xb0
[  270.730239]  [<ffffffff817b6bae>] entry_SYSCALL_64_fastpath+0x12/0x76

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-25 00:13:18 -07:00
David S. Miller c5e40ee287 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	net/bridge/br_mdb.c

br_mdb.c conflict was a function call being removed to fix a bug in
'net' but whose signature was changed in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-23 00:41:16 -07:00
Thomas Graf 614732eaa1 openvswitch: Use regular VXLAN net_device device
This gets rid of all OVS specific VXLAN code in the receive and
transmit path by using a VXLAN net_device to represent the vport.
Only a small shim layer remains which takes care of handling the
VXLAN specific OVS Netlink configuration.

Unexports vxlan_sock_add(), vxlan_sock_release(), vxlan_xmit_skb()
since they are no longer needed.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:07 -07:00
Thomas Graf e7030878fc fib: Add fib rule match on tunnel id
This add the ability to select a routing table based on the tunnel
id which allows to maintain separate routing tables for each virtual
tunnel network.

ip rule add from all tunnel-id 100 lookup 100
ip rule add from all tunnel-id 200 lookup 200

A new static key controls the collection of metadata at tunnel level
upon demand.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:06 -07:00
Thomas Graf f38a9eb1f7 dst: Metadata destinations
Introduces a new dst_metadata which enables to carry per packet metadata
between forwarding and processing elements via the skb->dst pointer.

The structure is set up to be a union. Thus, each separate type of
metadata requires its own dst instance. If demand arises to carry
multiple types of metadata concurrently, metadata dst entries can be
made stackable.

The metadata dst entry is refcnt'ed as expected for now but a non
reference counted use is possible if the reference is forced before
queueing the skb.

In order to allow allocating dsts with variable length, the existing
dst_alloc() is split into a dst_alloc() and dst_init() function. The
existing dst_init() function to initialize the subsystem is being
renamed to dst_subsys_init() to make it clear what is what.

The check before ip_route_input() is changed to ignore metadata dsts
and drop the dst inside the routing function thus allowing to interpret
metadata in a later commit.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:05 -07:00
Roopa Prabhu ffce41962e lwtunnel: support dst output redirect function
This patch introduces lwtunnel_output function to call corresponding
lwtunnels output function to xmit the packet.

It adds two variants lwtunnel_output and lwtunnel_output6 for ipv4 and
ipv6 respectively today. But this is subject to change when lwtstate will
reside in dst or dst_metadata (as per upstream discussions).

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:04 -07:00
Roopa Prabhu 499a242568 lwtunnel: infrastructure for handling light weight tunnels like mpls
Provides infrastructure to parse/dump/store encap information for
light weight tunnels like mpls. Encap information for such tunnels
is associated with fib routes.

This infrastructure is based on previous suggestions from
Eric Biederman to follow the xfrm infrastructure.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 10:39:03 -07:00
Konstantin Khlebnikov 8bf4ada2e2 net: ratelimit warnings about dst entry refcount underflow or overflow
Kernel generates a lot of warnings when dst entry reference counter
overflows and becomes negative. That bug was seen several times at
machines with outdated 3.10.y kernels. Most like it's already fixed
in upstream. Anyway that flood completely kills machine and makes
further debugging impossible.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-21 00:11:19 -07:00
Alexei Starovoitov 4d9c5c53ac test_bpf: add bpf_skb_vlan_push/pop() tests
improve accuracy of timing in test_bpf and add two stress tests:
- {skb->data[0], get_smp_processor_id} repeated 2k times
- {skb->data[0], vlan_push} x 68 followed by {skb->data[0], vlan_pop} x 68

1st test is useful to test performance of JIT implementation of BPF_LD_ABS
together with BPF_CALL instructions.
2nd test is stressing skb_vlan_push/pop logic together with skb->data access
via BPF_LD_ABS insn which checks that re-caching of skb->data is done correctly.

In order to call bpf_skb_vlan_push() from test_bpf.ko have to add
three export_symbol_gpl.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-20 20:52:32 -07:00
Alexei Starovoitov 4e10df9a60 bpf: introduce bpf_skb_vlan_push/pop() helpers
Allow eBPF programs attached to TC qdiscs call skb_vlan_push/pop via
helper functions. These functions may change skb->data/hlen which are
cached by some JITs to improve performance of ld_abs/ld_ind instructions.
Therefore JITs need to recognize bpf_skb_vlan_push/pop() calls,
re-compute header len and re-cache skb->data/hlen back into cpu registers.
Note, skb->data/hlen are not directly accessible from the programs,
so any changes to skb->data done either by these helpers or by other
TC actions are safe.

eBPF JIT supported by three architectures:
- arm64 JIT is using bpf_load_pointer() without caching, so it's ok as-is.
- x64 JIT re-caches skb->data/hlen unconditionally after vlan_push/pop calls
  (experiments showed that conditional re-caching is slower).
- s390 JIT falls back to interpreter for now when bpf_skb_vlan_push() is present
  in the program (re-caching is tbd).

These helpers allow more scalable handling of vlan from the programs.
Instead of creating thousands of vlan netdevs on top of eth0 and attaching
TC+ingress+bpf to all of them, the program can be attached to eth0 directly
and manipulate vlans as necessary.

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-20 20:52:31 -07:00