Commit Graph

62 Commits

Author SHA1 Message Date
Tariq Toukan 28581b9c2c bond: Disable TLS features indication
Bond agnostically interacts with TLS device-offload requests via the
.ndo_sk_get_lower_dev operation. Return value is true iff bond
guarantees fixed mapping between the TLS connection and a lower netdev.

Due to this nature, the bond TLS device offload features are not
explicitly controllable in the bond layer. As of today, these are
read-only values based on the evaluation of bond_sk_check().  However,
this indication might be incorrect and misleading, when the feature bits
are "fixed" by some dependency features.  For example,
NETIF_F_HW_TLS_TX/RX are forcefully cleared in case the corresponding
checksum offload is disabled. But in fact the bond ability to still
offload TLS connections to the lower device is not hurt.

This means that these bits can not be trusted, and hence better become
unused.

This patch revives some old discussion [1] and proposes a much simpler
solution: Clear the bond's TLS features bits. Everyone should stop
reading them.

[1] https://lore.kernel.org/netdev/20210526095747.22446-1-tariqt@nvidia.com/

Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20221025105300.4718-1-tariqt@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-10-27 12:45:38 +02:00
Benjamin Poirier 1d9a143ee3 net: bonding: Share lacpdu_mcast_addr definition
There are already a few definitions of arrays containing
MULTICAST_LACPDU_ADDR and the next patch will add one more use. These all
contain the same constant data so define one common instance for all
bonding code.

Signed-off-by: Benjamin Poirier <bpoirier@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-09-16 14:34:01 +01:00
Vladimir Oltean 06799a9085 net: bonding: replace dev_trans_start() with the jiffies of the last ARP/NS
The bonding driver piggybacks on time stamps kept by the network stack
for the purpose of the netdev TX watchdog, and this is problematic
because it does not work with NETIF_F_LLTX devices.

It is hard to say why the driver looks at dev_trans_start() of the
slave->dev, considering that this is updated even by non-ARP/NS probes
sent by us, and even by traffic not sent by us at all (for example PTP
on physical slave devices). ARP monitoring in active-backup mode appears
to still work even if we track only the last TX time of actual ARP
probes.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-03 19:20:12 -07:00
Hangbin Liu 0a2ff7cc8a Bonding: add per-port priority for failover re-selection
Add per port priority support for bonding active slave re-selection during
failover. A higher number means higher priority in selection. The primary
slave still has the highest priority. This option also follows the
primary_reselect rules.

This option could only be configured via netlink.

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Jonathan Toppins <jtoppins@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-24 11:27:59 +01:00
Hangbin Liu c4caa500ff bonding: guard ns_targets by CONFIG_IPV6
Guard ns_targets in struct bond_params by CONFIG_IPV6, which could save
256 bytes if IPv6 not configed. Also add this protection for function
bond_is_ip6_target_ok() and bond_get_targets_ip6().

Remove the IS_ENABLED() check for bond_opts[] as this will make
BOND_OPT_NS_TARGETS uninitialized if CONFIG_IPV6 not enabled. Add
a dummy bond_option_ns_ip6_targets_set() for this situation.

Fixes: 4e24be018e ("bonding: add new parameter ns_targets")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Acked-by: Jonathan Toppins <jtoppins@redhat.com>
Link: https://lore.kernel.org/r/20220531063727.224043-1-liuhangbin@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-06-01 11:18:55 +02:00
Eric Dumazet 625788b584 net: add per-cpu storage and net->core_stats
Before adding yet another possibly contended atomic_long_t,
it is time to add per-cpu storage for existing ones:
 dev->tx_dropped, dev->rx_dropped, and dev->rx_nohandler

Because many devices do not have to increment such counters,
allocate the per-cpu storage on demand, so that dev_get_stats()
does not have to spend considerable time folding zero counters.

Note that some drivers have abused these counters which
were supposed to be only used by core networking stack.

v4: should use per_cpu_ptr() in dev_get_stats() (Jakub)
v3: added a READ_ONCE() in netdev_core_stats_alloc() (Paolo)
v2: add a missing include (reported by kernel test robot <lkp@intel.com>)
    Change in netdev_core_stats_alloc() (Jakub)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: jeffreyji <jeffreyji@google.com>
Reviewed-by: Brian Vazquez <brianvv@google.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20220311051420.2608812-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-11 23:17:24 -08:00
Hangbin Liu 129e3c1bab bonding: add new option ns_ip6_target
This patch add a new bonding option ns_ip6_target, which correspond
to the arp_ip_target. With this we set IPv6 targets and send IPv6 NS
request to determine the health of the link.

For other related options like the validation, we still use
arp_validate, and will change to ns_validate later.

Note: the sysfs configuration support was removed based on
https://lore.kernel.org/netdev/8863.1645071997@famine

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-21 12:13:45 +00:00
Hangbin Liu 4e24be018e bonding: add new parameter ns_targets
Add a new bonding parameter ns_targets to store IPv6 address.
Add required bond_ns_send/rcv functions first before adding
IPv6 address option setting.

Add two functions bond_send/rcv_validate so we can send/recv
ARP and NS at the same time.

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-21 12:13:45 +00:00
Jakub Kicinski 8b0fdcdc3a net: remove bond_slave_has_mac_rcu()
No caller since v3.16.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-27 13:53:26 +00:00
Hangbin Liu aa6034678e bonding: use rcu_dereference_rtnl when get bonding active slave
bond_option_active_slave_get_rcu() should not be used in rtnl_mutex as it
use rcu_dereference(). Replace to rcu_dereference_rtnl() so we also can use
this function in rtnl protected context.

With this update, we can rmeove the rcu_read_lock/unlock in
bonding .ndo_eth_ioctl and .get_ts_info.

Reported-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Fixes: 94dd016ae5 ("bond: pass get_ts_info and SIOC[SG]HWTSTAMP ioctl to active device")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-24 11:57:38 +00:00
Hangbin Liu 5944b5abd8 Bonding: add arp_missed_max option
Currently, we use hard code number to verify if we are in the
arp_interval timeslice. But some user may want to reduce/extend
the verify timeslice. With the similar team option 'missed_max'
the uers could change that number based on their own environment.

Acked-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-30 12:15:58 +00:00
Jonathan Toppins 891a88f4f5 bonding: remove extraneous definitions from bonding.h
All of the symbols either only exist in bond_options.c or nowhere at
all. These symbols were verified to not exist in the code base by
using `git grep` and their removal was verified by compiling bonding.ko.

Signed-off-by: Jonathan Toppins <jtoppins@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-11 14:57:31 -07:00
Jakub Kicinski d1a4e0a957 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
bpf-next 2021-08-10

We've added 31 non-merge commits during the last 8 day(s) which contain
a total of 28 files changed, 3644 insertions(+), 519 deletions(-).

1) Native XDP support for bonding driver & related BPF selftests, from Jussi Maki.

2) Large batch of new BPF JIT tests for test_bpf.ko that came out as a result from
   32-bit MIPS JIT development, from Johan Almbladh.

3) Rewrite of netcnt BPF selftest and merge into test_progs, from Stanislav Fomichev.

4) Fix XDP bpf_prog_test_run infra after net to net-next merge, from Andrii Nakryiko.

5) Follow-up fix in unix_bpf_update_proto() to enforce socket type, from Cong Wang.

6) Fix bpf-iter-tcp4 selftest to print the correct dest IP, from Jose Blanquicet.

7) Various misc BPF XDP sample improvements, from Niklas Söderlund, Matthew Cover,
   and Muhammad Falak R Wani.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (31 commits)
  bpf, tests: Add tail call test suite
  bpf, tests: Add tests for BPF_CMPXCHG
  bpf, tests: Add tests for atomic operations
  bpf, tests: Add test for 32-bit context pointer argument passing
  bpf, tests: Add branch conversion JIT test
  bpf, tests: Add word-order tests for load/store of double words
  bpf, tests: Add tests for ALU operations implemented with function calls
  bpf, tests: Add more ALU64 BPF_MUL tests
  bpf, tests: Add more BPF_LSH/RSH/ARSH tests for ALU64
  bpf, tests: Add more ALU32 tests for BPF_LSH/RSH/ARSH
  bpf, tests: Add more tests of ALU32 and ALU64 bitwise operations
  bpf, tests: Fix typos in test case descriptions
  bpf, tests: Add BPF_MOV tests for zero and sign extension
  bpf, tests: Add BPF_JMP32 test cases
  samples, bpf: Add an explict comment to handle nested vlan tagging.
  selftests/bpf: Add tests for XDP bonding
  selftests/bpf: Fix xdp_tx.c prog section name
  net, core: Allow netdev_lower_get_next_private_rcu in bh context
  bpf, devmap: Exclude XDP broadcast to master device
  net, bonding: Add XDP support to the bonding driver
  ...
====================

Link: https://lore.kernel.org/r/20210810130038.16927-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-10 07:53:22 -07:00
Jussi Maki 9e2ee5c7e7 net, bonding: Add XDP support to the bonding driver
XDP is implemented in the bonding driver by transparently delegating
the XDP program loading, removal and xmit operations to the bonding
slave devices. The overall goal of this work is that XDP programs
can be attached to a bond device *without* any further changes (or
awareness) necessary to the program itself, meaning the same XDP
program can be attached to a native device but also a bonding device.

Semantics of XDP_TX when attached to a bond are equivalent in such
setting to the case when a tc/BPF program would be attached to the
bond, meaning transmitting the packet out of the bond itself using one
of the bond's configured xmit methods to select a slave device (rather
than XDP_TX on the slave itself). Handling of XDP_TX to transmit
using the configured bonding mechanism is therefore implemented by
rewriting the BPF program return value in bpf_prog_run_xdp. To avoid
performance impact this check is guarded by a static key, which is
incremented when a XDP program is loaded onto a bond device. This
approach was chosen to avoid changes to drivers implementing XDP. If
the slave device does not match the receive device, then XDP_REDIRECT
is transparently used to perform the redirection in order to have
the network driver release the packet from its RX ring. The bonding
driver hashing functions have been refactored to allow reuse with
xdp_buff's to avoid code duplication.

The motivation for this change is to enable use of bonding (and
802.3ad) in hairpinning L4 load-balancers such as [1] implemented with
XDP and also to transparently support bond devices for projects that
use XDP given most modern NICs have dual port adapters. An alternative
to this approach would be to implement 802.3ad in user-space and
implement the bonding load-balancing in the XDP program itself, but
is rather a cumbersome endeavor in terms of slave device management
(e.g. by watching netlink) and requires separate programs for native
vs bond cases for the orchestrator. A native in-kernel implementation
overcomes these issues and provides more flexibility.

Below are benchmark results done on two machines with 100Gbit
Intel E810 (ice) NIC and with 32-core 3970X on sending machine, and
16-core 3950X on receiving machine. 64 byte packets were sent with
pktgen-dpdk at full rate. Two issues [2, 3] were identified with the
ice driver, so the tests were performed with iommu=off and patch [2]
applied. Additionally the bonding round robin algorithm was modified
to use per-cpu tx counters as high CPU load (50% vs 10%) and high rate
of cache misses were caused by the shared rr_tx_counter (see patch
2/3). The statistics were collected using "sar -n dev -u 1 10". On top
of that, for ice, further work is in progress on improving the XDP_TX
numbers [4].

 -----------------------|  CPU  |--| rxpck/s |--| txpck/s |----
 without patch (1 dev):
   XDP_DROP:              3.15%      48.6Mpps
   XDP_TX:                3.12%      18.3Mpps     18.3Mpps
   XDP_DROP (RSS):        9.47%      116.5Mpps
   XDP_TX (RSS):          9.67%      25.3Mpps     24.2Mpps
 -----------------------
 with patch, bond (1 dev):
   XDP_DROP:              3.14%      46.7Mpps
   XDP_TX:                3.15%      13.9Mpps     13.9Mpps
   XDP_DROP (RSS):        10.33%     117.2Mpps
   XDP_TX (RSS):          10.64%     25.1Mpps     24.0Mpps
 -----------------------
 with patch, bond (2 devs):
   XDP_DROP:              6.27%      92.7Mpps
   XDP_TX:                6.26%      17.6Mpps     17.5Mpps
   XDP_DROP (RSS):       11.38%      117.2Mpps
   XDP_TX (RSS):         14.30%      28.7Mpps     27.4Mpps
 --------------------------------------------------------------

RSS: Receive Side Scaling, e.g. the packets were sent to a range of
destination IPs.

  [1]: https://cilium.io/blog/2021/05/20/cilium-110#standalonelb
  [2]: https://lore.kernel.org/bpf/20210601113236.42651-1-maciej.fijalkowski@intel.com/T/#t
  [3]: https://lore.kernel.org/bpf/CAHn8xckNXci+X_Eb2WMv4uVYjO2331UWB2JLtXr_58z0Av8+8A@mail.gmail.com/
  [4]: https://lore.kernel.org/bpf/20210805230046.28715-1-maciej.fijalkowski@intel.com/T/#t

Signed-off-by: Jussi Maki <joamaki@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Cc: Magnus Karlsson <magnus.karlsson@intel.com>
Link: https://lore.kernel.org/bpf/20210731055738.16820-4-joamaki@gmail.com
2021-08-09 23:20:14 +02:00
Hangbin Liu 3a755cd8b7 bonding: add new option lacp_active
Add an option lacp_active, which is similar with team's runner.active.
This option specifies whether to send LACPDU frames periodically. If set
on, the LACPDU frames are sent along with the configured lacp_rate
setting. If set off, the LACPDU frames acts as "speak when spoken to".

Note, the LACPDU state frames still will be sent when init or unbind port.

v2: remove module parameter

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-03 11:50:22 +01:00
Taehee Yoo 9a5605505d bonding: Add struct bond_ipesc to manage SA
bonding has been supporting ipsec offload.
When SA is added, bonding just passes SA to its own active real interface.
But it doesn't manage SA.
So, when events(add/del real interface, active real interface change, etc)
occur, bonding can't handle that well because It doesn't manage SA.
So some problems(panic, UAF, refcnt leak)occur.

In order to make it stable, it should manage SA.
That's the reason why struct bond_ipsec is added.
When a new SA is added to bonding interface, it is stored in the
bond_ipsec list. And the SA is passed to a current active real interface.
If events occur, it uses bond_ipsec data to handle these events.
bond->ipsec_list is protected by bond->ipsec_lock.

If a current active real interface is changed, the following logic works.
1. delete all SAs from old active real interface
2. Add all SAs to the new active real interface.
3. If a new active real interface doesn't support ipsec offload or SA's
option, it sets real_dev to NULL.

Fixes: 18cb261afd ("bonding: support hardware encryption offload to slaves")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-06 10:36:59 -07:00
Jussi Maki 848ca9182a net: bonding: Use per-cpu rr_tx_counter
The round-robin rr_tx_counter was shared across CPUs leading to
significant cache thrashing at high packet rates. This patch switches
the round-robin packet counter to use a per-cpu variable to decide
the destination slave.

On a test with 2x100Gbit ICE nic with pktgen_sample_04_many_flows.sh
(-s 64 -t 32) the tx rate was 19.6Mpps before and 22.3Mpps after
this patch.

"perf top -e cache_misses" before:
    12.31%  [bonding]       [k] bond_xmit_roundrobin_slave_get
    10.59%  [sch_fq_codel]  [k] fq_codel_dequeue
     9.34%  [kernel]        [k] skb_release_data
after:
    15.42%  [sch_fq_codel]  [k] fq_codel_dequeue
    10.06%  [kernel]        [k] __memset
     9.12%  [kernel]        [k] skb_release_data

Signed-off-by: Jussi Maki <joamaki@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-15 11:26:15 -07:00
Tariq Toukan dc5809f9e2 net/bonding: Declare TLS RX device offload support
Following the description in previous patch (for TX):
As the bond interface is being bypassed by the TLS module, interacting
directly against the lower devs, there is no way for the bond interface
to disable its device offload capabilities, as long as the mode/policy
config allows it.
Hence, the feature flag is not directly controllable, but just reflects
the offload status based on the logic under bond_sk_check().

Here we just declare RX device offload support, and expose it via the
NETIF_F_HW_TLS_RX flag.

Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Boris Pismenny <borisp@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-18 20:48:40 -08:00
Tariq Toukan 89df6a8104 net/bonding: Implement TLS TX device offload
Implement TLS TX device offload for bonding interfaces.
This allows kTLS sockets running on a bond to benefit from the
device offload on capable lower devices.

To allow a simple and fast maintenance of the TLS context in SW and
lower devices, we bind the TLS socket to a specific lower dev.
To achieve a behavior similar to SW kTLS, we support only balance-xor
and 802.3ad modes, with xmit_hash_policy=layer3+4. This is enforced
in bond_sk_check(), done in a previous patch.

For the above configuration, the SW implementation keeps picking the
same exact lower dev for all the socket's SKBs. The device offload
behaves similarly, making the decision once at the connection creation.

Per socket, the TLS module should work directly with the lowest netdev
in chain, to call the tls_dev_ops operations.

As the bond interface is being bypassed by the TLS module, interacting
directly against the lower devs, there is no way for the bond interface
to disable its device offload capabilities, as long as the mode/policy
config allows it.
Hence, the feature flag is not directly controllable, but just reflects
the current offload status based on the logic under bond_sk_check().

Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Boris Pismenny <borisp@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-18 20:48:40 -08:00
Tariq Toukan 007feb87fb net/bonding: Implement ndo_sk_get_lower_dev
Add ndo_sk_get_lower_dev() implementation for bond interfaces.

Support only for the cases where the socket's and SKBs' hash
yields identical value for the whole connection lifetime.

Here we restrict it to L3+4 sockets only, with
xmit_hash_policy==LAYER34 and bond modes xor/802.3ad.

Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Boris Pismenny <borisp@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-01-18 20:48:40 -08:00
Jarod Wilson 007ab53455 bonding: fix feature flag setting at init time
Don't try to adjust XFRM support flags if the bond device isn't yet
registered. Bad things can currently happen when netdev_change_features()
is called without having wanted_features fully filled in yet. This code
runs both on post-module-load mode changes, as well as at module init
time, and when run at module init time, it is before register_netdevice()
has been called and filled in wanted_features. The empty wanted_features
led to features also getting emptied out, which was definitely not the
intended behavior, so prevent that from happening.

Originally, I'd hoped to stop adjusting wanted_features at all in the
bonding driver, as it's documented as being something only the network
core should touch, but we actually do need to do this to properly update
both the features and wanted_features fields when changing the bond type,
or we get to a situation where ethtool sees:

    esp-hw-offload: off [requested on]

I do think we should be using netdev_update_features instead of
netdev_change_features here though, so we only send notifiers when the
features actually changed.

Fixes: a3b658cfb6 ("bonding: allow xfrm offload setup post-module-load")
Reported-by: Ivan Vecera <ivecera@redhat.com>
Suggested-by: Ivan Vecera <ivecera@redhat.com>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Link: https://lore.kernel.org/r/20201205172229.576587-1-jarod@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-12-08 11:26:08 -08:00
Jamie Iles b9ad3e9f5a bonding: wait for sysfs kobject destruction before freeing struct slave
syzkaller found that with CONFIG_DEBUG_KOBJECT_RELEASE=y, releasing a
struct slave device could result in the following splat:

  kobject: 'bonding_slave' (00000000cecdd4fe): kobject_release, parent 0000000074ceb2b2 (delayed 1000)
  bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
  ------------[ cut here ]------------
  ODEBUG: free active (active state 0) object type: timer_list hint: workqueue_select_cpu_near kernel/workqueue.c:1549 [inline]
  ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x98 kernel/workqueue.c:1600
  WARNING: CPU: 1 PID: 842 at lib/debugobjects.c:485 debug_print_object+0x180/0x240 lib/debugobjects.c:485
  Kernel panic - not syncing: panic_on_warn set ...
  CPU: 1 PID: 842 Comm: kworker/u4:4 Tainted: G S                5.9.0-rc8+ #96
  Hardware name: linux,dummy-virt (DT)
  Workqueue: netns cleanup_net
  Call trace:
   dump_backtrace+0x0/0x4d8 include/linux/bitmap.h:239
   show_stack+0x34/0x48 arch/arm64/kernel/traps.c:142
   __dump_stack lib/dump_stack.c:77 [inline]
   dump_stack+0x174/0x1f8 lib/dump_stack.c:118
   panic+0x360/0x7a0 kernel/panic.c:231
   __warn+0x244/0x2ec kernel/panic.c:600
   report_bug+0x240/0x398 lib/bug.c:198
   bug_handler+0x50/0xc0 arch/arm64/kernel/traps.c:974
   call_break_hook+0x160/0x1d8 arch/arm64/kernel/debug-monitors.c:322
   brk_handler+0x30/0xc0 arch/arm64/kernel/debug-monitors.c:329
   do_debug_exception+0x184/0x340 arch/arm64/mm/fault.c:864
   el1_dbg+0x48/0xb0 arch/arm64/kernel/entry-common.c:65
   el1_sync_handler+0x170/0x1c8 arch/arm64/kernel/entry-common.c:93
   el1_sync+0x80/0x100 arch/arm64/kernel/entry.S:594
   debug_print_object+0x180/0x240 lib/debugobjects.c:485
   __debug_check_no_obj_freed lib/debugobjects.c:967 [inline]
   debug_check_no_obj_freed+0x200/0x430 lib/debugobjects.c:998
   slab_free_hook mm/slub.c:1536 [inline]
   slab_free_freelist_hook+0x190/0x210 mm/slub.c:1577
   slab_free mm/slub.c:3138 [inline]
   kfree+0x13c/0x460 mm/slub.c:4119
   bond_free_slave+0x8c/0xf8 drivers/net/bonding/bond_main.c:1492
   __bond_release_one+0xe0c/0xec8 drivers/net/bonding/bond_main.c:2190
   bond_slave_netdev_event drivers/net/bonding/bond_main.c:3309 [inline]
   bond_netdev_event+0x8f0/0xa70 drivers/net/bonding/bond_main.c:3420
   notifier_call_chain+0xf0/0x200 kernel/notifier.c:83
   __raw_notifier_call_chain kernel/notifier.c:361 [inline]
   raw_notifier_call_chain+0x44/0x58 kernel/notifier.c:368
   call_netdevice_notifiers_info+0xbc/0x150 net/core/dev.c:2033
   call_netdevice_notifiers_extack net/core/dev.c:2045 [inline]
   call_netdevice_notifiers net/core/dev.c:2059 [inline]
   rollback_registered_many+0x6a4/0xec0 net/core/dev.c:9347
   unregister_netdevice_many.part.0+0x2c/0x1c0 net/core/dev.c:10509
   unregister_netdevice_many net/core/dev.c:10508 [inline]
   default_device_exit_batch+0x294/0x338 net/core/dev.c:10992
   ops_exit_list.isra.0+0xec/0x150 net/core/net_namespace.c:189
   cleanup_net+0x44c/0x888 net/core/net_namespace.c:603
   process_one_work+0x96c/0x18c0 kernel/workqueue.c:2269
   worker_thread+0x3f0/0xc30 kernel/workqueue.c:2415
   kthread+0x390/0x498 kernel/kthread.c:292
   ret_from_fork+0x10/0x18 arch/arm64/kernel/entry.S:925

This is a potential use-after-free if the sysfs nodes are being accessed
whilst removing the struct slave, so wait for the object destruction to
complete before freeing the struct slave itself.

Fixes: 07699f9a7c ("bonding: add sysfs /slave dir for bond slave devices.")
Fixes: a068aab422 ("bonding: Fix reference count leak in bond_sysfs_slave_add.")
Cc: Qiushi Wu <wu000273@umn.edu>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Jamie Iles <jamie@nuviainc.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20201120142827.879226-1-jamie@nuviainc.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-21 13:07:00 -08:00
Jarod Wilson a3b658cfb6 bonding: allow xfrm offload setup post-module-load
At the moment, bonding xfrm crypto offload can only be set up if the bonding
module is loaded with active-backup mode already set. We need to be able to
make this work with bonds set to AB after the bonding driver has already
been loaded.

So what's done here is:

1) move #define BOND_XFRM_FEATURES to net/bonding.h so it can be used
by both bond_main.c and bond_options.c
2) set BOND_XFRM_FEATURES in bond_dev->hw_features universally, rather than
only when loading in AB mode
3) wire up xfrmdev_ops universally too
4) disable BOND_XFRM_FEATURES in bond_dev->features if not AB
5) exit early (non-AB case) from bond_ipsec_offload_ok, to prevent a
performance hit from traversing into the underlying drivers
5) toggle BOND_XFRM_FEATURES in bond_dev->wanted_features and call
netdev_change_features() from bond_option_mode_set()

In my local testing, I can change bonding modes back and forth on the fly,
have hardware offload work when I'm in AB, and see no performance penalty
to non-AB software encryption, despite having xfrm bits all wired up for
all modes now.

Fixes: 18cb261afd ("bonding: support hardware encryption offload to slaves")
Reported-by: Huy Nguyen <huyn@mellanox.com>
CC: Saeed Mahameed <saeedm@mellanox.com>
CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: "David S. Miller" <davem@davemloft.net>
CC: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
CC: Jakub Kicinski <kuba@kernel.org>
CC: Steffen Klassert <steffen.klassert@secunet.com>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: netdev@vger.kernel.org
CC: intel-wired-lan@lists.osuosl.org
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-01 15:53:32 -07:00
Jarod Wilson 18cb261afd bonding: support hardware encryption offload to slaves
Currently, this support is limited to active-backup mode, as I'm not sure
about the feasilibity of mapping an xfrm_state's offload handle to
multiple hardware devices simultaneously, and we rely on being able to
pass some hints to both the xfrm and NIC driver about whether or not
they're operating on a slave device.

I've tested this atop an Intel x520 device (ixgbe) using libreswan in
transport mode, succesfully achieving ~4.3Gbps throughput with netperf
(more or less identical to throughput on a bare NIC in this system),
as well as successful failover and recovery mid-netperf.

v2: just use CONFIG_XFRM_OFFLOAD for wrapping, isolate more code with it

CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: "David S. Miller" <davem@davemloft.net>
CC: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
CC: Jakub Kicinski <kuba@kernel.org>
CC: Steffen Klassert <steffen.klassert@secunet.com>
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: netdev@vger.kernel.org
CC: intel-wired-lan@lists.osuosl.org
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-06-22 15:38:57 -07:00
Saeed Mahameed 76cd622fe2 Merge branch 'mlx5-next' of git://git.kernel.org/pub/scm/linux/kernel/git/mellanox/linux
This merge includes updates to bonding driver needed for the rdma stack,
to avoid conflicts with the RDMA branch.

Maor Gottlieb Says:

====================
Bonding: Add support to get xmit slave

The following series adds support to get the LAG master xmit slave by
introducing new .ndo - ndo_get_xmit_slave. Every LAG module can
implement it and it first implemented in the bond driver.
This is follow-up to the RFC discussion [1].

The main motivation for doing this is for drivers that offload part
of the LAG functionality. For example, Mellanox Connect-X hardware
implements RoCE LAG which selects the TX affinity when the resources
are created and port is remapped when it goes down.

The first part of this patchset introduces the new .ndo and add the
support to the bonding module.

The second part adds support to get the RoCE LAG xmit slave by building
skb of the RoCE packet based on the AH attributes and call to the new
.ndo.

The third part change the mlx5 driver driver to set the QP's affinity
port according to the slave which found by the .ndo.
====================

Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
2020-05-09 01:05:30 -07:00
Eric Dumazet ae46f184bc bonding: propagate transmit status
Currently, bonding always returns NETDEV_TX_OK to its caller.

It is worth trying to be more accurate : TCP for instance
can have different recovery strategies if it can have more
precise status, if packet was dropped by slave qdisc.

This is especially important when host is under stress.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-07 18:11:07 -07:00
Eric Dumazet f78ed2204d netpoll: accept NULL np argument in netpoll_send_skb()
netpoll_send_skb() callers seem to leak skb if
the np pointer is NULL. While this should not happen, we
can make the code more robust.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-07 18:11:07 -07:00
Cong Wang e7511f560f bonding: remove useless stats_lock_key
After commit b3e80d44f5
("bonding: fix lockdep warning in bond_get_stats()") the dynamic
key is no longer necessary, as we compute nest level at run-time.
So, we can just remove it to save some lockdep key entries.

Test commands:
 ip link add bond0 type bond
 ip link add bond1 type bond
 ip link set bond0 master bond1
 ip link set bond0 nomaster
 ip link set bond1 master bond0

Reported-and-tested-by: syzbot+aaa6fa4949cc5d9b7b25@syzkaller.appspotmail.com
Cc: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-04 12:05:56 -07:00
Maor Gottlieb 6b447e76ed bonding: Add array of all slaves
Keep all slaves in array so it could be used to get the xmit slave
assume all the slaves are active.
The logic to add slave to the array is like the usable slaves, except
that we also add slaves that currently can't transmit - not up or active.

Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
2020-05-01 12:15:38 -07:00
Maor Gottlieb ed7d4f023b bonding: Rename slave_arr to usable_slaves
Rename slave_arr to usable_slaves, since we will have two arrays,
one for the usable slaves and the other to all slaves.

Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Reviewed-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
2020-05-01 12:15:37 -07:00
Gustavo A. R. Silva 749db09304 bonding: Replace zero-length array with flexible-array member
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2020-02-28 12:08:37 -08:00
Jay Vosburgh 1899bb3251 bonding: fix state transition issue in link monitoring
Since de77ecd4ef ("bonding: improve link-status update in
mii-monitoring"), the bonding driver has utilized two separate variables
to indicate the next link state a particular slave should transition to.
Each is used to communicate to a different portion of the link state
change commit logic; one to the bond_miimon_commit function itself, and
another to the state transition logic.

	Unfortunately, the two variables can become unsynchronized,
resulting in incorrect link state transitions within bonding.  This can
cause slaves to become stuck in an incorrect link state until a
subsequent carrier state transition.

	The issue occurs when a special case in bond_slave_netdev_event
sets slave->link directly to BOND_LINK_FAIL.  On the next pass through
bond_miimon_inspect after the slave goes carrier up, the BOND_LINK_FAIL
case will set the proposed next state (link_new_state) to BOND_LINK_UP,
but the new_link to BOND_LINK_DOWN.  The setting of the final link state
from new_link comes after that from link_new_state, and so the slave
will end up incorrectly in _DOWN state.

	Resolve this by combining the two variables into one.

Reported-by: Aleksei Zakharov <zakharov.a.g@yandex.ru>
Reported-by: Sha Zhang <zhangsha.zhang@huawei.com>
Cc: Mahesh Bandewar <maheshb@google.com>
Fixes: de77ecd4ef ("bonding: improve link-status update in mii-monitoring")
Signed-off-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-05 17:40:16 -08:00
Taehee Yoo f3b0a18bb6 net: remove unnecessary variables and callback
This patch removes variables and callback these are related to the nested
device structure.
devices that can be nested have their own nest_level variable that
represents the depth of nested devices.
In the previous patch, new {lower/upper}_level variables are added and
they replace old private nest_level variable.
So, this patch removes all 'nest_level' variables.

In order to avoid lockdep warning, ->ndo_get_lock_subclass() was added
to get lockdep subclass value, which is actually lower nested depth value.
But now, they use the dynamic lockdep key to avoid lockdep warning instead
of the subclass.
So, this patch removes ->ndo_get_lock_subclass() callback.

Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-24 14:53:49 -07:00
Taehee Yoo 089bca2cae bonding: use dynamic lockdep key instead of subclass
All bonding device has same lockdep key and subclass is initialized with
nest_level.
But actual nest_level value can be changed when a lower device is attached.
And at this moment, the subclass should be updated but it seems to be
unsafe.
So this patch makes bonding use dynamic lockdep key instead of the
subclass.

Test commands:
    ip link add bond0 type bond

    for i in {1..5}
    do
	    let A=$i-1
	    ip link add bond$i type bond
	    ip link set bond$i master bond$A
    done
    ip link set bond5 master bond0

Splat looks like:
[  307.992912] WARNING: possible recursive locking detected
[  307.993656] 5.4.0-rc3+ #96 Tainted: G        W
[  307.994367] --------------------------------------------
[  307.995092] ip/761 is trying to acquire lock:
[  307.995710] ffff8880513aac60 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xb8/0x500 [bonding]
[  307.997045]
	       but task is already holding lock:
[  307.997923] ffff88805fcbac60 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xb8/0x500 [bonding]
[  307.999215]
	       other info that might help us debug this:
[  308.000251]  Possible unsafe locking scenario:

[  308.001137]        CPU0
[  308.001533]        ----
[  308.001915]   lock(&(&bond->stats_lock)->rlock#2/2);
[  308.002609]   lock(&(&bond->stats_lock)->rlock#2/2);
[  308.003302]
		*** DEADLOCK ***

[  308.004310]  May be due to missing lock nesting notation

[  308.005319] 3 locks held by ip/761:
[  308.005830]  #0: ffffffff9fcc42b0 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x466/0x8a0
[  308.006894]  #1: ffff88805fcbac60 (&(&bond->stats_lock)->rlock#2/2){+.+.}, at: bond_get_stats+0xb8/0x500 [bonding]
[  308.008243]  #2: ffffffff9f9219c0 (rcu_read_lock){....}, at: bond_get_stats+0x9f/0x500 [bonding]
[  308.009422]
	       stack backtrace:
[  308.010124] CPU: 0 PID: 761 Comm: ip Tainted: G        W         5.4.0-rc3+ #96
[  308.011097] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  308.012179] Call Trace:
[  308.012601]  dump_stack+0x7c/0xbb
[  308.013089]  __lock_acquire+0x269d/0x3de0
[  308.013669]  ? register_lock_class+0x14d0/0x14d0
[  308.014318]  lock_acquire+0x164/0x3b0
[  308.014858]  ? bond_get_stats+0xb8/0x500 [bonding]
[  308.015520]  _raw_spin_lock_nested+0x2e/0x60
[  308.016129]  ? bond_get_stats+0xb8/0x500 [bonding]
[  308.017215]  bond_get_stats+0xb8/0x500 [bonding]
[  308.018454]  ? bond_arp_rcv+0xf10/0xf10 [bonding]
[  308.019710]  ? rcu_read_lock_held+0x90/0xa0
[  308.020605]  ? rcu_read_lock_sched_held+0xc0/0xc0
[  308.021286]  ? bond_get_stats+0x9f/0x500 [bonding]
[  308.021953]  dev_get_stats+0x1ec/0x270
[  308.022508]  bond_get_stats+0x1d1/0x500 [bonding]

Fixes: d3fff6c443 ("net: add netdev_lockdep_set_classes() helper")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-24 14:53:48 -07:00
Vincent Bernat 07a4ddec3c bonding: add an option to specify a delay between peer notifications
Currently, gratuitous ARP/ND packets are sent every `miimon'
milliseconds. This commit allows a user to specify a custom delay
through a new option, `peer_notif_delay'.

Like for `updelay' and `downdelay', this delay should be a multiple of
`miimon' to avoid managing an additional work queue. The configuration
logic is copied from `updelay' and `downdelay'. However, the default
value cannot be set using a module parameter: Netlink or sysfs should
be used to configure this feature.

When setting `miimon' to 100 and `peer_notif_delay' to 500, we can
observe the 500 ms delay is respected:

    20:30:19.354693 ARP, Request who-has 203.0.113.10 tell 203.0.113.10, length 28
    20:30:19.874892 ARP, Request who-has 203.0.113.10 tell 203.0.113.10, length 28
    20:30:20.394919 ARP, Request who-has 203.0.113.10 tell 203.0.113.10, length 28
    20:30:20.914963 ARP, Request who-has 203.0.113.10 tell 203.0.113.10, length 28

In bond_mii_monitor(), I have tried to keep the lock logic readable.
The change is due to the fact we cannot rely on a notification to
lower the value of `bond->send_peer_notif' as `NETDEV_NOTIFY_PEERS' is
only triggered once every N times, while we need to decrement the
counter each time.

iproute2 also needs to be updated to be able to specify this new
attribute through `ip link'.

Signed-off-by: Vincent Bernat <vincent@bernat.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-04 12:30:48 -07:00
Jarod Wilson 5237ff79b2 bonding: add slave_foo printk macros
Where possible, we generally want both the bond master and the relevant slave
information in message output. Standardize the format using new slave_*
printk macros.

Suggested-by: Joe Perches <joe@perches.com>
CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: netdev@vger.kernel.org
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-09 13:36:01 -07:00
Mahesh Bandewar d4859d749a bonding: avoid possible dead-lock
Syzkaller reported this on a slightly older kernel but it's still
applicable to the current kernel -

======================================================
WARNING: possible circular locking dependency detected
4.18.0-next-20180823+ #46 Not tainted
------------------------------------------------------
syz-executor4/26841 is trying to acquire lock:
00000000dd41ef48 ((wq_completion)bond_dev->name){+.+.}, at: flush_workqueue+0x2db/0x1e10 kernel/workqueue.c:2652

but task is already holding lock:
00000000768ab431 (rtnl_mutex){+.+.}, at: rtnl_lock net/core/rtnetlink.c:77 [inline]
00000000768ab431 (rtnl_mutex){+.+.}, at: rtnetlink_rcv_msg+0x412/0xc30 net/core/rtnetlink.c:4708

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #2 (rtnl_mutex){+.+.}:
       __mutex_lock_common kernel/locking/mutex.c:925 [inline]
       __mutex_lock+0x171/0x1700 kernel/locking/mutex.c:1073
       mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1088
       rtnl_lock+0x17/0x20 net/core/rtnetlink.c:77
       bond_netdev_notify drivers/net/bonding/bond_main.c:1310 [inline]
       bond_netdev_notify_work+0x44/0xd0 drivers/net/bonding/bond_main.c:1320
       process_one_work+0xc73/0x1aa0 kernel/workqueue.c:2153
       worker_thread+0x189/0x13c0 kernel/workqueue.c:2296
       kthread+0x35a/0x420 kernel/kthread.c:246
       ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415

-> #1 ((work_completion)(&(&nnw->work)->work)){+.+.}:
       process_one_work+0xc0b/0x1aa0 kernel/workqueue.c:2129
       worker_thread+0x189/0x13c0 kernel/workqueue.c:2296
       kthread+0x35a/0x420 kernel/kthread.c:246
       ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:415

-> #0 ((wq_completion)bond_dev->name){+.+.}:
       lock_acquire+0x1e4/0x4f0 kernel/locking/lockdep.c:3901
       flush_workqueue+0x30a/0x1e10 kernel/workqueue.c:2655
       drain_workqueue+0x2a9/0x640 kernel/workqueue.c:2820
       destroy_workqueue+0xc6/0x9d0 kernel/workqueue.c:4155
       __alloc_workqueue_key+0xef9/0x1190 kernel/workqueue.c:4138
       bond_init+0x269/0x940 drivers/net/bonding/bond_main.c:4734
       register_netdevice+0x337/0x1100 net/core/dev.c:8410
       bond_newlink+0x49/0xa0 drivers/net/bonding/bond_netlink.c:453
       rtnl_newlink+0xef4/0x1d50 net/core/rtnetlink.c:3099
       rtnetlink_rcv_msg+0x46e/0xc30 net/core/rtnetlink.c:4711
       netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2454
       rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4729
       netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
       netlink_unicast+0x5a0/0x760 net/netlink/af_netlink.c:1343
       netlink_sendmsg+0xa18/0xfc0 net/netlink/af_netlink.c:1908
       sock_sendmsg_nosec net/socket.c:622 [inline]
       sock_sendmsg+0xd5/0x120 net/socket.c:632
       ___sys_sendmsg+0x7fd/0x930 net/socket.c:2115
       __sys_sendmsg+0x11d/0x290 net/socket.c:2153
       __do_sys_sendmsg net/socket.c:2162 [inline]
       __se_sys_sendmsg net/socket.c:2160 [inline]
       __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2160
       do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
       entry_SYSCALL_64_after_hwframe+0x49/0xbe

other info that might help us debug this:

Chain exists of:
  (wq_completion)bond_dev->name --> (work_completion)(&(&nnw->work)->work) --> rtnl_mutex

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(rtnl_mutex);
                               lock((work_completion)(&(&nnw->work)->work));
                               lock(rtnl_mutex);
  lock((wq_completion)bond_dev->name);

 *** DEADLOCK ***

1 lock held by syz-executor4/26841:

stack backtrace:
CPU: 1 PID: 26841 Comm: syz-executor4 Not tainted 4.18.0-next-20180823+ #46
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x2b4 lib/dump_stack.c:113
 print_circular_bug.isra.34.cold.55+0x1bd/0x27d kernel/locking/lockdep.c:1222
 check_prev_add kernel/locking/lockdep.c:1862 [inline]
 check_prevs_add kernel/locking/lockdep.c:1975 [inline]
 validate_chain kernel/locking/lockdep.c:2416 [inline]
 __lock_acquire+0x3449/0x5020 kernel/locking/lockdep.c:3412
 lock_acquire+0x1e4/0x4f0 kernel/locking/lockdep.c:3901
 flush_workqueue+0x30a/0x1e10 kernel/workqueue.c:2655
 drain_workqueue+0x2a9/0x640 kernel/workqueue.c:2820
 destroy_workqueue+0xc6/0x9d0 kernel/workqueue.c:4155
 __alloc_workqueue_key+0xef9/0x1190 kernel/workqueue.c:4138
 bond_init+0x269/0x940 drivers/net/bonding/bond_main.c:4734
 register_netdevice+0x337/0x1100 net/core/dev.c:8410
 bond_newlink+0x49/0xa0 drivers/net/bonding/bond_netlink.c:453
 rtnl_newlink+0xef4/0x1d50 net/core/rtnetlink.c:3099
 rtnetlink_rcv_msg+0x46e/0xc30 net/core/rtnetlink.c:4711
 netlink_rcv_skb+0x172/0x440 net/netlink/af_netlink.c:2454
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:4729
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x5a0/0x760 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0xa18/0xfc0 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:622 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:632
 ___sys_sendmsg+0x7fd/0x930 net/socket.c:2115
 __sys_sendmsg+0x11d/0x290 net/socket.c:2153
 __do_sys_sendmsg net/socket.c:2162 [inline]
 __se_sys_sendmsg net/socket.c:2160 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2160
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x457089
Code: fd b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b4 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f2df20a5c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f2df20a66d4 RCX: 0000000000457089
RDX: 0000000000000000 RSI: 0000000020000180 RDI: 0000000000000003
RBP: 0000000000930140 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004d40b8 R14: 00000000004c8ad8 R15: 0000000000000001

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-26 20:22:19 -07:00
Petr Machata eeed992b77 net: Add lag.h, net_lag_port_dev_txable()
LAG devices (team or bond) recognize for each one of their slave devices
whether LAG traffic is going to be sent through that device. Bond calls
such devices "active", team calls them "txable". When this state
changes, a NETDEV_CHANGELOWERSTATE notification is distributed, together
with a netdev_notifier_changelowerstate_info structure that for LAG
devices includes a tx_enabled flag that refers to the new state. The
notification thus makes it possible to react to the changes in txability
in drivers.

However there's no way to query txability from the outside on demand.
That is problematic namely for mlxsw, which when resolving ERSPAN packet
path, may encounter a LAG device, and needs to determine which of the
slaves it should choose.

To that end, introduce a new function, net_lag_port_dev_txable(), which
determines whether a given slave device is "active" or
"txable" (depending on the flavor of the LAG device). That function then
dispatches to per-LAG-flavor helpers, bond_is_active_slave_dev() resp.
team_port_dev_txable().

Because there currently is no good place where net_lag_port_dev_txable()
should be added, introduce a new header file, lag.h, which should from
now on hold any logic common to both team and bond. (But keep
netif_is_lag_master() together with the rest of netif_is_*_master()
functions).

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-11 23:10:19 -07:00
Debabrata Banerjee e79c105574 bonding: allow use of tx hashing in balance-alb
The rx load balancing provided by balance-alb is not mutually
exclusive with using hashing for tx selection, and should provide a decent
speed increase because this eliminates spinlocks and cache contention.

Signed-off-by: Debabrata Banerjee <dbanerje@akamai.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-16 12:15:11 -04:00
Debabrata Banerjee 21706ee8a4 bonding: send learning packets for vlans on slave
There was a regression at some point from the intended functionality of
commit f60c3704e8 ("bonding: Fix alb mode to only use first level
vlans.")

Given the return value vlan_get_encap_level() we need to store the nest
level of the bond device, and then compare the vlan's encap level to
this. Without this, this check always fails and learning packets are
never sent.

In addition, this same commit caused a regression in the behavior of
balance_alb, which requires learning packets be sent for all interfaces
using the slave's mac in order to load balance properly. For vlan's
that have not set a user mac, we can send after checking one bit.
Otherwise we need send the set mac, albeit defeating rx load balancing
for that vlan.

Signed-off-by: Debabrata Banerjee <dbanerje@akamai.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-11 11:50:41 -04:00
Xin Long ef5201c83d bonding: remove rtmsg_ifinfo called after bond_lower_state_changed
After the patch 'rtnetlink: bring NETDEV_CHANGELOWERSTATE event
process back to rtnetlink_event', bond_lower_state_changed would
generate NETDEV_CHANGEUPPER event which would send a notification
to userspace in rtnetlink_event.

There's no need to call rtmsg_ifinfo to send the notification
any more. So this patch is to remove it from these places after
bond_lower_state_changed.

Besides, after this, rtmsg_ifinfo is not needed to be exported.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-25 10:54:39 +09:00
David Ahern 33eaf2a6eb net: Add extack to ndo_add_slave
Pass extack to do_set_master and down to ndo_add_slave

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-04 21:39:33 -07:00
Andreas Born ad729bc9ac bonding: require speed/duplex only for 802.3ad, alb and tlb
The patch c4adfc822b ("bonding: make speed, duplex setting consistent
with link state") puts the link state to down if
bond_update_speed_duplex() cannot retrieve speed and duplex settings.
Assumably the patch was written with 802.3ad mode in mind which relies
on link speed/duplex settings. For other modes like active-backup these
settings are not required. Thus, only for these other modes, this patch
reintroduces support for slaves that do not support reporting speed or
duplex such as wireless devices. This fixes the regression reported in
bug 196547 (https://bugzilla.kernel.org/show_bug.cgi?id=196547).

Fixes: c4adfc822b ("bonding: make speed, duplex setting consistent
with link state")
Signed-off-by: Andreas Born <futur.andy@googlemail.com>
Acked-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-11 14:21:42 -07:00
Mahesh Bandewar ea8ffc0818 bonding: fix wq initialization for links created via netlink
Earlier patch 4493b81bea ("bonding: initialize work-queues during
creation of bond") moved the work-queue initialization from bond_open()
to bond_create(). However this caused the link those are created using
netlink 'create bond option' (ip link add bondX type bond); create the
new trunk without initializing work-queues. Prior to the above mentioned
change, ndo_open was in both paths and things worked correctly. The
consequence is visible in the report shared by Joe Stringer -

I've noticed that this patch breaks bonding within namespaces if
you're not careful to perform device cleanup correctly.

Here's my repro script, you can run on any net-next with this patch
and you'll start seeing some weird behaviour:

ip netns add foo
ip li add veth0 type veth peer name veth0+ netns foo
ip li add veth1 type veth peer name veth1+ netns foo
ip netns exec foo ip li add bond0 type bond
ip netns exec foo ip li set dev veth0+ master bond0
ip netns exec foo ip li set dev veth1+ master bond0
ip netns exec foo ip addr add dev bond0 192.168.0.1/24
ip netns exec foo ip li set dev bond0 up
ip li del dev veth0
ip li del dev veth1

The second to last command segfaults, last command hangs. rtnl is now
permanently locked. It's not a problem if you take bond0 down before
deleting veths, or delete bond0 before deleting veths. If you delete
either end of the veth pair as per above, either inside or outside the
namespace, it hits this problem.

Here's some kernel logs:
[ 1221.801610] bond0: Enslaving veth0+ as an active interface with an up link
[ 1224.449581] bond0: Enslaving veth1+ as an active interface with an up link
[ 1281.193863] bond0: Releasing backup interface veth0+
[ 1281.193866] bond0: the permanent HWaddr of veth0+ -
16:bf:fb:e0:b8:43 - is still in use by bond0 - set the HWaddr of
veth0+ to a different address to avoid conflicts
[ 1281.193867] ------------[ cut here ]------------
[ 1281.193873] WARNING: CPU: 0 PID: 2024 at kernel/workqueue.c:1511
__queue_delayed_work+0x13f/0x150
[ 1281.193873] Modules linked in: bonding veth openvswitch nf_nat_ipv6
nf_nat_ipv4 nf_nat autofs4 nfsd auth_rpcgss nfs_acl binfmt_misc nfs
lockd grace sunrpc fscache ppdev vmw_balloon coretemp psmouse
serio_raw vmwgfx ttm drm_kms_helper vmw_vmci netconsole parport_pc
configfs drm i2c_piix4 fb_sys_fops syscopyarea sysfillrect sysimgblt
shpchp mac_hid nf_conntrack_ipv6 nf_defrag_ipv6 nf_conntrack_ipv4
nf_defrag_ipv4 nf_conntrack libcrc32c lp parport hid_generic usbhid
hid mptspi mptscsih e1000 mptbase ahci libahci
[ 1281.193905] CPU: 0 PID: 2024 Comm: ip Tainted: G        W
4.10.0-bisect-bond-v0.14 #37
[ 1281.193906] Hardware name: VMware, Inc. VMware Virtual
Platform/440BX Desktop Reference Platform, BIOS 6.00 09/30/2014
[ 1281.193906] Call Trace:
[ 1281.193912]  dump_stack+0x63/0x89
[ 1281.193915]  __warn+0xd1/0xf0
[ 1281.193917]  warn_slowpath_null+0x1d/0x20
[ 1281.193918]  __queue_delayed_work+0x13f/0x150
[ 1281.193920]  queue_delayed_work_on+0x27/0x40
[ 1281.193929]  bond_change_active_slave+0x25b/0x670 [bonding]
[ 1281.193932]  ? synchronize_rcu_expedited+0x27/0x30
[ 1281.193935]  __bond_release_one+0x489/0x510 [bonding]
[ 1281.193939]  ? addrconf_notify+0x1b7/0xab0
[ 1281.193942]  bond_netdev_event+0x2c5/0x2e0 [bonding]
[ 1281.193944]  ? netconsole_netdev_event+0x124/0x190 [netconsole]
[ 1281.193947]  notifier_call_chain+0x49/0x70
[ 1281.193948]  raw_notifier_call_chain+0x16/0x20
[ 1281.193950]  call_netdevice_notifiers_info+0x35/0x60
[ 1281.193951]  rollback_registered_many+0x23b/0x3e0
[ 1281.193953]  unregister_netdevice_many+0x24/0xd0
[ 1281.193955]  rtnl_delete_link+0x3c/0x50
[ 1281.193956]  rtnl_dellink+0x8d/0x1b0
[ 1281.193960]  rtnetlink_rcv_msg+0x95/0x220
[ 1281.193962]  ? __kmalloc_node_track_caller+0x35/0x280
[ 1281.193964]  ? __netlink_lookup+0xf1/0x110
[ 1281.193966]  ? rtnl_newlink+0x830/0x830
[ 1281.193967]  netlink_rcv_skb+0xa7/0xc0
[ 1281.193969]  rtnetlink_rcv+0x28/0x30
[ 1281.193970]  netlink_unicast+0x15b/0x210
[ 1281.193971]  netlink_sendmsg+0x319/0x390
[ 1281.193974]  sock_sendmsg+0x38/0x50
[ 1281.193975]  ___sys_sendmsg+0x25c/0x270
[ 1281.193978]  ? mem_cgroup_commit_charge+0x76/0xf0
[ 1281.193981]  ? page_add_new_anon_rmap+0x89/0xc0
[ 1281.193984]  ? lru_cache_add_active_or_unevictable+0x35/0xb0
[ 1281.193985]  ? __handle_mm_fault+0x4e9/0x1170
[ 1281.193987]  __sys_sendmsg+0x45/0x80
[ 1281.193989]  SyS_sendmsg+0x12/0x20
[ 1281.193991]  do_syscall_64+0x6e/0x180
[ 1281.193993]  entry_SYSCALL64_slow_path+0x25/0x25
[ 1281.193995] RIP: 0033:0x7f6ec122f5a0
[ 1281.193995] RSP: 002b:00007ffe69e89c48 EFLAGS: 00000246 ORIG_RAX:
000000000000002e
[ 1281.193997] RAX: ffffffffffffffda RBX: 00007ffe69e8dd60 RCX: 00007f6ec122f5a0
[ 1281.193997] RDX: 0000000000000000 RSI: 00007ffe69e89c90 RDI: 0000000000000003
[ 1281.193998] RBP: 00007ffe69e89c90 R08: 0000000000000000 R09: 0000000000000003
[ 1281.193999] R10: 00007ffe69e89a10 R11: 0000000000000246 R12: 0000000058f14b9f
[ 1281.193999] R13: 0000000000000000 R14: 00000000006473a0 R15: 00007ffe69e8e450
[ 1281.194001] ---[ end trace 713a77486cbfbfa3 ]---

Fixes: 4493b81bea ("bonding: initialize work-queues during creation of bond")
Reported-by: Joe Stringer <joe@ovn.org>
Tested-by: Joe Stringer <joe@ovn.org>
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Acked-by: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-21 15:28:37 -04:00
Jarod Wilson faeeb317a5 bonding: attempt to better support longer hw addresses
People are using bonding over Infiniband IPoIB connections, and who knows
what else. Infiniband has a hardware address length of 20 octets
(INFINIBAND_ALEN), and the network core defines a MAX_ADDR_LEN of 32.
Various places in the bonding code are currently hard-wired to 6 octets
(ETH_ALEN), such as the 3ad code, which I've left untouched here. Besides,
only alb is currently possible on Infiniband links right now anyway, due
to commit 1533e77315, so the alb code is where most of the changes are.

One major component of this change is the addition of a bond_hw_addr_copy
function that takes a length argument, instead of using ether_addr_copy
everywhere that hardware addresses need to be copied about. The other
major component of this change is converting the bonding code from using
struct sockaddr for address storage to struct sockaddr_storage, as the
former has an address storage space of only 14, while the latter is 128
minus a few, which is necessary to support bonding over device with up to
MAX_ADDR_LEN octet hardware addresses. Additionally, this probably fixes
up some memory corruption issues with the current code, where it's
possible to write an infiniband hardware address into a sockaddr declared
on the stack.

Lightly tested on a dual mlx4 IPoIB setup, which properly shows a 20-octet
hardware address now:

$ cat /proc/net/bonding/bond0
Ethernet Channel Bonding Driver: v3.7.1 (April 27, 2011)

Bonding Mode: fault-tolerance (active-backup) (fail_over_mac active)
Primary Slave: mlx4_ib0 (primary_reselect always)
Currently Active Slave: mlx4_ib0
MII Status: up
MII Polling Interval (ms): 100
Up Delay (ms): 100
Down Delay (ms): 100

Slave Interface: mlx4_ib0
MII Status: up
Speed: Unknown
Duplex: Unknown
Link Failure Count: 0
Permanent HW addr:
80:00:02:08:fe:80:00:00:00:00:00:00:e4:1d:2d:03:00:1d:67:01
Slave queue ID: 0

Slave Interface: mlx4_ib1
MII Status: up
Speed: Unknown
Duplex: Unknown
Link Failure Count: 0
Permanent HW addr:
80:00:02:09:fe:80:00:00:00:00:00:01:e4:1d:2d:03:00:1d:67:02
Slave queue ID: 0

Also tested with a standard 1Gbps NIC bonding setup (with a mix of
e1000 and e1000e cards), running LNST's bonding tests.

CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: netdev@vger.kernel.org
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-04-05 18:44:54 -07:00
Mahesh Bandewar f307668bfc bonding: split bond_set_slave_link_state into two parts
Split the function into two (a) propose (b) commit phase without
changing the semantics for the original API.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-27 21:11:49 -07:00
Alexey Dobriyan c7d03a00b5 netns: make struct pernet_operations::id unsigned int
Make struct pernet_operations::id unsigned.

There are 2 reasons to do so:

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

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

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

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

  roughly translates to

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

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

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

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

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

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

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

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

However, overall balance is in negative direction:

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

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18 10:59:15 -05:00
Al Viro 4ad41c1e26 bonding: quit messing with IOCTL
The only remaining users are issuing SIOCGMIIPHY and SIOCGMIIREG,
neither of which deals with userland pointers.  Simply calling
->ndo_do_ioctl() is fine; no messing with set_fs() is needed.
It used to mess with SIOCETHTOOL, which would've needed set_fs(),
but that has been killed in "[NET] ethtool ops are the only way"
9 years ago...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-09-27 21:15:21 -04:00
Eric Dumazet f87fda00b6 bonding: prevent out of bound accesses
ether_addr_equal_64bits() requires some care about its arguments,
namely that 8 bytes might be read, even if last 2 byte values are not
used.

KASan detected a violation with null_mac_addr and lacpdu_mcast_addr
in bond_3ad.c

Same problem with mac_bcast[] and mac_v6_allmcast[] in bond_alb.c :
Although the 8-byte alignment was there, KASan would detect out
of bound accesses.

Fixes: 815117adaf ("bonding: use ether_addr_equal_unaligned for bond addr compare")
Fixes: bb54e58929 ("bonding: Verify RX LACPDU has proper dest mac-addr")
Fixes: 885a136c52 ("bonding: use compare_ether_addr_64bits() in ALB")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-07-01 06:06:09 -04:00
Eric Dumazet fe30937b65 bonding: fix bond_get_stats()
bond_get_stats() can be called from rtnetlink (with RTNL held)
or from /proc/net/dev seq handler (with RCU held)

The logic added in commit 5f0c5f73e5 ("bonding: make global bonding
stats more reliable") kind of assumed only one cpu could run there.

If multiple threads are reading /proc/net/dev, stats can be really
messed up after a while.

A second problem is that some fields are 32bit, so we need to properly
handle the wrap around problem.

Given that RTNL is not always held, we need to use
bond_for_each_slave_rcu().

Fixes: 5f0c5f73e5 ("bonding: make global bonding stats more reliable")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Andy Gospodarek <gospo@cumulusnetworks.com>
Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-03-18 23:14:15 -04:00