The commit 56bfa7ee ("unregister_netdevice : move RTM_DELLINK to
until after ndo_uninit") tried to do this ealier but while doing so
it created a problem. Unfortunately the delayed rtmsg_ifinfo() also
delayed call to fill_info(). So this translated into asking driver
to remove private state and then query it's private state. This
could have catastropic consequences.

This change breaks the rtmsg_ifinfo() into two parts - one takes the
precise snapshot of the device by called fill_info() before calling
the ndo_uninit() and the second part sends the notification using
collected snapshot.

It was brought to notice when last link is deleted from an ipvlan device
when it has free-ed the port and the subsequent .fill_info() call is
trying to get the info from the port.

kernel: [  255.139429] ------------[ cut here ]------------
kernel: [  255.139439] WARNING: CPU: 12 PID: 11173 at net/core/rtnetlink.c:2238 rtmsg_ifinfo+0x100/0x110()
kernel: [  255.139493] Modules linked in: ipvlan bonding w1_therm ds2482 wire cdc_acm ehci_pci ehci_hcd i2c_dev i2c_i801 i2c_core msr cpuid bnx2x ptp pps_core mdio libcrc32c
kernel: [  255.139513] CPU: 12 PID: 11173 Comm: ip Not tainted 3.18.0-smp-DEV #167
kernel: [  255.139514] Hardware name: Intel RML,PCH/Ibis_QC_18, BIOS 1.0.10 05/15/2012
kernel: [  255.139515]  0000000000000009 ffff880851b6b828 ffffffff815d87f4 00000000000000e0
kernel: [  255.139516]  0000000000000000 ffff880851b6b868 ffffffff8109c29c 0000000000000000
kernel: [  255.139518]  00000000ffffffa6 00000000000000d0 ffffffff81aaf580 0000000000000011
kernel: [  255.139520] Call Trace:
kernel: [  255.139527]  [<ffffffff815d87f4>] dump_stack+0x46/0x58
kernel: [  255.139531]  [<ffffffff8109c29c>] warn_slowpath_common+0x8c/0xc0
kernel: [  255.139540]  [<ffffffff8109c2ea>] warn_slowpath_null+0x1a/0x20
kernel: [  255.139544]  [<ffffffff8150d570>] rtmsg_ifinfo+0x100/0x110
kernel: [  255.139547]  [<ffffffff814f78b5>] rollback_registered_many+0x1d5/0x2d0
kernel: [  255.139549]  [<ffffffff814f79cf>] unregister_netdevice_many+0x1f/0xb0
kernel: [  255.139551]  [<ffffffff8150acab>] rtnl_dellink+0xbb/0x110
kernel: [  255.139553]  [<ffffffff8150da90>] rtnetlink_rcv_msg+0xa0/0x240
kernel: [  255.139557]  [<ffffffff81329283>] ? rhashtable_lookup_compare+0x43/0x80
kernel: [  255.139558]  [<ffffffff8150d9f0>] ? __rtnl_unlock+0x20/0x20
kernel: [  255.139562]  [<ffffffff8152cb11>] netlink_rcv_skb+0xb1/0xc0
kernel: [  255.139563]  [<ffffffff8150a495>] rtnetlink_rcv+0x25/0x40
kernel: [  255.139565]  [<ffffffff8152c398>] netlink_unicast+0x178/0x230
kernel: [  255.139567]  [<ffffffff8152c75f>] netlink_sendmsg+0x30f/0x420
kernel: [  255.139571]  [<ffffffff814e0b0c>] sock_sendmsg+0x9c/0xd0
kernel: [  255.139575]  [<ffffffff811d1d7f>] ? rw_copy_check_uvector+0x6f/0x130
kernel: [  255.139577]  [<ffffffff814e11c9>] ? copy_msghdr_from_user+0x139/0x1b0
kernel: [  255.139578]  [<ffffffff814e1774>] ___sys_sendmsg+0x304/0x310
kernel: [  255.139581]  [<ffffffff81198723>] ? handle_mm_fault+0xca3/0xde0
kernel: [  255.139585]  [<ffffffff811ebc4c>] ? destroy_inode+0x3c/0x70
kernel: [  255.139589]  [<ffffffff8108e6ec>] ? __do_page_fault+0x20c/0x500
kernel: [  255.139597]  [<ffffffff811e8336>] ? dput+0xb6/0x190
kernel: [  255.139606]  [<ffffffff811f05f6>] ? mntput+0x26/0x40
kernel: [  255.139611]  [<ffffffff811d2b94>] ? __fput+0x174/0x1e0
kernel: [  255.139613]  [<ffffffff814e2129>] __sys_sendmsg+0x49/0x90
kernel: [  255.139615]  [<ffffffff814e2182>] SyS_sendmsg+0x12/0x20
kernel: [  255.139617]  [<ffffffff815df092>] system_call_fastpath+0x12/0x17
kernel: [  255.139619] ---[ end trace 5e6703e87d984f6b ]---
Signed-off-by: NMahesh Bandewar <maheshb@google.com>
Reported-by: NToshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Roopa Prabhu <roopa@cumulusnetworks.com>
Cc: David S. Miller <davem@davemloft.net>
Acked-by: NEric Dumazet <edumazet@google.com>
Acked-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

To allow brport device to return current brport flags set on port.  Add
returned flags to nested IFLA_PROTINFO netlink msg built in dflt getlink.
With this change, netlink msg returned for bridge_getlink contains the port's
offloaded flag settings (the port's SELF settings).
Signed-off-by: NScott Feldman <sfeldma@gmail.com>
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Acked-by: NAndy Gospodarek <gospo@cumulusnetworks.com>
Acked-by: NThomas Graf <tgraf@suug.ch>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The netdevice represents a port in a switch, it will expose
IFLA_PHYS_SWITCH_ID value via rtnl. Two netdevices with the same value
belong to one physical switch.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Reviewed-by: NThomas Graf <tgraf@suug.ch>
Acked-by: NJohn Fastabend <john.r.fastabend@intel.com>
Acked-by: NAndy Gospodarek <gospo@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

So this can be reused for identification of other "items" as well.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Reviewed-by: NThomas Graf <tgraf@suug.ch>
Acked-by: NJohn Fastabend <john.r.fastabend@intel.com>
Acked-by: NAndy Gospodarek <gospo@cumulusnetworks.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Do the work of parsing NDA_VLAN directly in rtnetlink code, pass simple
u16 vid to drivers from there.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Acked-by: NAndy Gospodarek <gospo@cumulusnetworks.com>
Acked-by: NJamal Hadi Salim <jhs@mojatatu.com>
Acked-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Only search for IFLA_EXT_MASK if the message actually carries a
ifinfomsg header and validate minimal length requirements for
IFLA_EXT_MASK.

Fixes: 6cbdceeb ("bridge: Dump vlan information from a bridge port")
Cc: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Payload is currently accessed blindly and may exceed valid message
boundaries.

Fixes: 407af329 ("bridge: Add netlink interface to configure vlans on bridge ports")
Cc: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Depending on which parameters were updated, the changes were not propagated via
the notifier chain and netlink.

The new flag has been set only when the change did not cause a call to the
notifier chain and/or to the netlink notification functions.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is no functional changes with this commit, it only prepares the next one.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The only effect of this patch is to print a warning if IFLA_LINKMODE is updated
and a following change fails.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The only effect of this patch is to print a warning if IFLA_TXQLEN is updated
and a following change fails.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 1d8faf48 ("net/core: Add VF link state control") added new
attribute to IFLA_VF_INFO group in rtnl_fill_ifinfo but did not adjust size
of the allocated memory in if_nlmsg_size/rtnl_vfinfo_size. As the result, we
may trigger warnings in rtnl_getlink and similar functions when many VF
links are enabled, as the information does not fit into the allocated skb.

Fixes: 1d8faf48 ("net/core: Add VF link state control")
Reported-by: NYulong Pei <ypei@redhat.com>
Signed-off-by: NJiri Benc <jbenc@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change cleans up ndo_dflt_fdb_del to drop the ENOTSUPP return value since
that isn't actually returned anywhere in the code.  As a result we are able to
drop a few lines by just defaulting this to -EINVAL.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This passes down NET_NAME_USER (or NET_NAME_ENUM) to alloc_netdev(),
for any device created over rtnetlink.

v9: restore reverse-christmas-tree order of local variables
Signed-off-by: NTom Gundersen <teg@jklm.no>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Extend alloc_netdev{,_mq{,s}}() to take name_assign_type as argument, and convert
all users to pass NET_NAME_UNKNOWN.

Coccinelle patch:

@@
expression sizeof_priv, name, setup, txqs, rxqs, count;
@@

(
-alloc_netdev_mqs(sizeof_priv, name, setup, txqs, rxqs)
+alloc_netdev_mqs(sizeof_priv, name, NET_NAME_UNKNOWN, setup, txqs, rxqs)
|
-alloc_netdev_mq(sizeof_priv, name, setup, count)
+alloc_netdev_mq(sizeof_priv, name, NET_NAME_UNKNOWN, setup, count)
|
-alloc_netdev(sizeof_priv, name, setup)
+alloc_netdev(sizeof_priv, name, NET_NAME_UNKNOWN, setup)
)

v9: move comments here from the wrong commit
Signed-off-by: NTom Gundersen <teg@jklm.no>
Reviewed-by: NDavid Herrmann <dh.herrmann@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Actually better than brctl showmacs because we can filter by bridge
port in the kernel.
The current bridge netlink interface doesnt scale when you have many
bridges each with large fdbs or even bridges with many bridge ports

And now for the science non-fiction novel you have all been
waiting for..

//lets see what bridge ports we have
root@moja-1:/configs/may30-iprt/bridge# ./bridge link show
8: eth1 state DOWN : <BROADCAST,MULTICAST> mtu 1500 master br0 state
disabled priority 32 cost 19
17: sw1-p1 state DOWN : <BROADCAST,NOARP> mtu 1500 master br0 state
disabled priority 32 cost 100

// show all..
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show
33:33:00:00:00:01 dev bond0 self permanent
33:33:00:00:00:01 dev dummy0 self permanent
33:33:00:00:00:01 dev ifb0 self permanent
33:33:00:00:00:01 dev ifb1 self permanent
33:33:00:00:00:01 dev eth0 self permanent
01:00:5e:00:00:01 dev eth0 self permanent
33:33:ff:22:01:01 dev eth0 self permanent
02:00:00:12:01:02 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:05 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:07 dev eth1 self permanent
33:33:00:00:00:01 dev eth1 self permanent
33:33:00:00:00:01 dev gretap0 self permanent
da:ac:46:27:d9:53 dev sw1-p1 vlan 0 master br0 permanent
33:33:00:00:00:01 dev sw1-p1 self permanent

//filter by bridge
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show br br0
02:00:00:12:01:02 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:05 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:07 dev eth1 self permanent
33:33:00:00:00:01 dev eth1 self permanent
da:ac:46:27:d9:53 dev sw1-p1 vlan 0 master br0 permanent
33:33:00:00:00:01 dev sw1-p1 self permanent

// bridge sw1 has no ports attached..
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show br sw1

//filter by port
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show brport eth1
02:00:00:12:01:02 vlan 0 master br0 permanent
00:17:42:8a:b4:05 vlan 0 master br0 permanent
00:17:42:8a:b4:07 self permanent
33:33:00:00:00:01 self permanent

// filter by port + bridge
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show br br0 brport
sw1-p1
da:ac:46:27:d9:53 vlan 0 master br0 permanent
33:33:00:00:00:01 self permanent

// for shits and giggles (as they say in New Brunswick), lets
// change the mac that br0 uses
// Note: a magical fdb entry with no brport is added ...
root@moja-1:/configs/may30-iprt/bridge# ip link set dev br0 address
02:00:00:12:01:04

// lets see if we can see the unicorn ..
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show
33:33:00:00:00:01 dev bond0 self permanent
33:33:00:00:00:01 dev dummy0 self permanent
33:33:00:00:00:01 dev ifb0 self permanent
33:33:00:00:00:01 dev ifb1 self permanent
33:33:00:00:00:01 dev eth0 self permanent
01:00:5e:00:00:01 dev eth0 self permanent
33:33:ff:22:01:01 dev eth0 self permanent
02:00:00:12:01:02 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:05 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:07 dev eth1 self permanent
33:33:00:00:00:01 dev eth1 self permanent
33:33:00:00:00:01 dev gretap0 self permanent
02:00:00:12:01:04 dev br0 vlan 0 master br0 permanent <=== there it is
da:ac:46:27:d9:53 dev sw1-p1 vlan 0 master br0 permanent
33:33:00:00:00:01 dev sw1-p1 self permanent

//can we see it if we filter by bridge?
root@moja-1:/configs/may30-iprt/bridge# ./bridge fdb show br br0
02:00:00:12:01:02 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:05 dev eth1 vlan 0 master br0 permanent
00:17:42:8a:b4:07 dev eth1 self permanent
33:33:00:00:00:01 dev eth1 self permanent
02:00:00:12:01:04 dev br0 vlan 0 master br0 permanent <=== there it is
da:ac:46:27:d9:53 dev sw1-p1 vlan 0 master br0 permanent
33:33:00:00:00:01 dev sw1-p1 self permanent
Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Dumping a bridge fdb dumps every fdb entry
held. With this change we are going to filter
on selected bridge port.
Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

So far, it is assumed that ops->setup is filled up. But there might be
case that ops might make sense even without ->setup. In that case,
forbid to newlink and dellink.

This allows to register simple rtnl link ops containing only ->kind.
That allows consistent way of passing device kind (either device-kind or
slave-kind) to userspace.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When running RHEL6 userspace on a current upstream kernel, "ip link"
fails to show VF information.

The reason is a kernel<->userspace API change introduced by commit
88c5b5ce ("rtnetlink: Call nlmsg_parse() with correct header length"),
after which the kernel does not see iproute2's IFLA_EXT_MASK attribute
in the netlink request.

iproute2 adjusted for the API change in its commit 63338dca4513
("libnetlink: Use ifinfomsg instead of rtgenmsg in rtnl_wilddump_req_filter").

The problem has been noticed before:
http://marc.info/?l=linux-netdev&m=136692296022182&w=2
(Subject: Re: getting VF link info seems to be broken in 3.9-rc8)

We can do better than tell those with old userspace to upgrade. We can
recognize the old iproute2 in the kernel by checking the netlink message
length. Even when including the IFLA_EXT_MASK attribute, its netlink
message is shorter than struct ifinfomsg.

With this patch "ip link" shows VF information in both old and new
iproute2 versions.
Signed-off-by: NMichal Schmidt <mschmidt@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 1d8faf48 (net/core: Add VF link state control) added VF link state
control to the netlink VF nested structure, but failed to add a proper entry
for the new structure into the VF policy table.  Add the missing entry so
the table and the actual data copied into the netlink nested struct are in
sync.
Signed-off-by: NDoug Ledford <dledford@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

unregister_netdevice_many() API is error prone and we had too
many bugs because of dangling LIST_HEAD on stacks.

See commit f87e6f47 ("net: dont leave active on stack LIST_HEAD")

In fact, instead of making sure no caller leaves an active list_head,
just force a list_del() in the callee. No one seems to need to access
the list after unregister_netdevice_many()
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is possible that ->newlink() fails before registering
the device, in this case we should just free it, it's
safe to call free_netdev().

Fixes: commit 0e0eee24 (net: correct error path in rtnl_newlink())
Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NCong Wang <cwang@twopensource.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

o min_tx_rate puts lower limit on the VF bandwidth. VF is guaranteed
  to have a bandwidth of at least this value.
  max_tx_rate puts cap on the VF bandwidth. VF can have a bandwidth
  of up to this value.

o A new handler set_vf_rate for attr IFLA_VF_RATE has been introduced
  which takes 4 arguments:
  netdev, VF number, min_tx_rate, max_tx_rate

o ndo_set_vf_rate replaces ndo_set_vf_tx_rate handler.

o Drivers that currently implement ndo_set_vf_tx_rate should now call
  ndo_set_vf_rate instead and reject attempt to set a minimum bandwidth
  greater than 0 for IFLA_VF_TX_RATE when IFLA_VF_RATE is not yet
  implemented by driver.

o If user enters only one of either min_tx_rate or max_tx_rate, then,
  userland should read back the other value from driver and set both
  for IFLA_VF_RATE.
  Drivers that have not yet implemented IFLA_VF_RATE should always
  return min_tx_rate as 0 when read from ip tool.

o If both IFLA_VF_TX_RATE and IFLA_VF_RATE options are specified, then
  IFLA_VF_RATE should override.

o Idea is to have consistent display of rate values to user.

o Usage example: -

  ./ip link set p4p1 vf 0 rate 900

  ./ip link show p4p1
  32: p4p1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode
  DEFAULT qlen 1000
    link/ether 00:0e:1e:08:b0:f0 brd ff:ff:ff:ff:ff:ff
    vf 0 MAC 3e:a0:ca:bd:ae:5a, tx rate 900 (Mbps), max_tx_rate 900Mbps
    vf 1 MAC f6:c6:7c:3f:3d:6c
    vf 2 MAC 56:32:43:98:d7:71
    vf 3 MAC d6:be:c3:b5:85:ff
    vf 4 MAC ee:a9:9a:1e:19:14
    vf 5 MAC 4a:d0:4c:07:52:18
    vf 6 MAC 3a:76:44:93:62:f9
    vf 7 MAC 82:e9:e7:e3:15:1a

  ./ip link set p4p1 vf 0 max_tx_rate 300 min_tx_rate 200

  ./ip link show p4p1
  32: p4p1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode
  DEFAULT qlen 1000
    link/ether 00:0e:1e:08:b0:f0 brd ff:ff:ff:ff:ff:ff
    vf 0 MAC 3e:a0:ca:bd:ae:5a, tx rate 300 (Mbps), max_tx_rate 300Mbps,
    min_tx_rate 200Mbps
    vf 1 MAC f6:c6:7c:3f:3d:6c
    vf 2 MAC 56:32:43:98:d7:71
    vf 3 MAC d6:be:c3:b5:85:ff
    vf 4 MAC ee:a9:9a:1e:19:14
    vf 5 MAC 4a:d0:4c:07:52:18
    vf 6 MAC 3a:76:44:93:62:f9
    vf 7 MAC 82:e9:e7:e3:15:1a

  ./ip link set p4p1 vf 0 max_tx_rate 600 rate 300

  ./ip link show p4p1
  32: p4p1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode
  DEFAULT qlen 1000
    link/ether 00:0e:1e:08:b0:f brd ff:ff:ff:ff:ff:ff
    vf 0 MAC 3e:a0:ca:bd:ae:5, tx rate 600 (Mbps), max_tx_rate 600Mbps,
    min_tx_rate 200Mbps
    vf 1 MAC f6:c6:7c:3f:3d:6c
    vf 2 MAC 56:32:43:98:d7:71
    vf 3 MAC d6:be:c3:b5:85:ff
    vf 4 MAC ee:a9:9a:1e:19:14
    vf 5 MAC 4a:d0:4c:07:52:18
    vf 6 MAC 3a:76:44:93:62:f9
    vf 7 MAC 82:e9:e7:e3:15:1a
Signed-off-by: NSucheta Chakraborty <sucheta.chakraborty@qlogic.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

From: Cong Wang <cwang@twopensource.com>

commit 50624c93 (net: Delay default_device_exit_batch until no
devices are unregistering) introduced rtnl_lock_unregistering() for
default_device_exit_batch(). Same race could happen we when rmmod a driver
which calls rtnl_link_unregister() as we call dev->destructor without rtnl
lock.

For long term, I think we should clean up the mess of netdev_run_todo()
and net namespce exit code.

Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NCong Wang <cwang@twopensource.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since 115c9b81 (rtnetlink: Fix problem with
buffer allocation), RTM_NEWLINK messages only contain the IFLA_VFINFO_LIST
attribute if they were solicited by a GETLINK message containing an
IFLA_EXT_MASK attribute with the RTEXT_FILTER_VF flag.

That was done because some user programs broke when they received more data
than expected - because IFLA_VFINFO_LIST contains information for each VF
it can become large if there are many VFs.

However, the IFLA_VF_PORTS attribute, supplied for devices which implement
ndo_get_vf_port (currently the 'enic' driver only), has the same problem.
It supplies per-VF information and can therefore become large, but it is
not currently conditional on the IFLA_EXT_MASK value.

Worse, it interacts badly with the existing EXT_MASK handling.  When
IFLA_EXT_MASK is not supplied, the buffer for netlink replies is fixed at
NLMSG_GOODSIZE.  If the information for IFLA_VF_PORTS exceeds this, then
rtnl_fill_ifinfo() returns -EMSGSIZE on the first message in a packet.
netlink_dump() will misinterpret this as having finished the listing and
omit data for this interface and all subsequent ones.  That can cause
getifaddrs(3) to enter an infinite loop.

This patch addresses the problem by only supplying IFLA_VF_PORTS when
IFLA_EXT_MASK is supplied with the RTEXT_FILTER_VF flag set.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Without IFLA_EXT_MASK specified, the information reported for a single
interface in response to RTM_GETLINK is expected to fit within a netlink
packet of NLMSG_GOODSIZE.

If it doesn't, however, things will go badly wrong,  When listing all
interfaces, netlink_dump() will incorrectly treat -EMSGSIZE on the first
message in a packet as the end of the listing and omit information for
that interface and all subsequent ones.  This can cause getifaddrs(3) to
enter an infinite loop.

This patch won't fix the problem, but it will WARN_ON() making it easier to
track down what's going wrong.
Signed-off-by: NDavid Gibson <david@gibson.dropbear.id.au>
Reviewed-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is possible by passing a netlink socket to a more privileged
executable and then to fool that executable into writing to the socket
data that happens to be valid netlink message to do something that
privileged executable did not intend to do.

To keep this from happening replace bare capable and ns_capable calls
with netlink_capable, netlink_net_calls and netlink_ns_capable calls.
Which act the same as the previous calls except they verify that the
opener of the socket had the desired permissions as well.
Reported-by: NAndy Lutomirski <luto@amacapital.net>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This allows to monitor carrier on/off transitions and detect link
flapping issues:
 - new /sys/class/net/X/carrier_changes
 - new rtnetlink IFLA_CARRIER_CHANGES (getlink)

Tested:
  - grep . /sys/class/net/*/carrier_changes
    + ip link set dev X down/up
    + plug/unplug cable
  - updated iproute2: prints IFLA_CARRIER_CHANGES
  - iproute2 20121211-2 (debian): unchanged behavior
Signed-off-by: NDavid Decotigny <decot@googlers.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 3ff661c3 ("net: rtnetlink notify events for FDB NTF_SELF adds and
deletes") reuses the function nlmsg_populate_fdb_fill() to notify fdb events.
But this function was used only for dump and thus was always setting the
flag NLM_F_MULTI, which is wrong in case of a single notification.

Libraries like libnl will wait forever for NLMSG_DONE.

CC: Thomas Graf <tgraf@suug.ch>
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The only place this is used outside rtnetlink.c is veth. So provide
wrapper function for this usage.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I saw the following BUG when ->newlink() fails in rtnl_newlink():

[   40.240058] kernel BUG at net/core/dev.c:6438!

this is due to free_netdev() is not supposed to be called before
netdev is completely unregistered, therefore it is not correct
to call free_netdev() here, at least for ops->newlink!=NULL case,
many drivers call it in ->destructor so that rtnl_unlock() will
take care of it, we probably don't need to do anything here.

Cc: David S. Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: NCong Wang <cwang@twopensource.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We should check whether rtnetlink link operations
are defined before calling get_slave_size().

Without this, the following oops can occur when
adding a tap device to OVS.

[   87.839553] BUG: unable to handle kernel NULL pointer dereference at 00000000000000a8
[   87.839595] IP: [<ffffffff813d47c0>] if_nlmsg_size+0xf0/0x220
[...]
[   87.840651] Call Trace:
[   87.840664]  [<ffffffff813d694b>] ? rtmsg_ifinfo+0x2b/0x100
[   87.840688]  [<ffffffff813c8340>] ? __netdev_adjacent_dev_insert+0x150/0x1a0
[   87.840718]  [<ffffffff813d6a50>] ? rtnetlink_event+0x30/0x40
[   87.840742]  [<ffffffff814b4144>] ? notifier_call_chain+0x44/0x70
[   87.840768]  [<ffffffff813c8946>] ? __netdev_upper_dev_link+0x3c6/0x3f0
[   87.840798]  [<ffffffffa0678d6c>] ? netdev_create+0xcc/0x160 [openvswitch]
[   87.840828]  [<ffffffffa06781ea>] ? ovs_vport_add+0x4a/0xd0 [openvswitch]
[   87.840857]  [<ffffffffa0670139>] ? new_vport+0x9/0x50 [openvswitch]
[   87.840884]  [<ffffffffa067279e>] ? ovs_vport_cmd_new+0x11e/0x210 [openvswitch]
[   87.840915]  [<ffffffff813f3efa>] ? genl_family_rcv_msg+0x19a/0x360
[   87.840941]  [<ffffffff813f40c0>] ? genl_family_rcv_msg+0x360/0x360
[   87.840967]  [<ffffffff813f4139>] ? genl_rcv_msg+0x79/0xc0
[   87.840991]  [<ffffffff813b6cf9>] ? __kmalloc_reserve.isra.25+0x29/0x80
[   87.841018]  [<ffffffff813f2389>] ? netlink_rcv_skb+0xa9/0xc0
[   87.841042]  [<ffffffff813f27cf>] ? genl_rcv+0x1f/0x30
[   87.841064]  [<ffffffff813f1988>] ? netlink_unicast+0xe8/0x1e0
[   87.841088]  [<ffffffff813f1d9a>] ? netlink_sendmsg+0x31a/0x750
[   87.841113]  [<ffffffff813aee96>] ? sock_sendmsg+0x86/0xc0
[   87.841136]  [<ffffffff813c960d>] ? __netdev_update_features+0x4d/0x200
[   87.841163]  [<ffffffff813ca94e>] ? ethtool_get_value+0x2e/0x50
[   87.841188]  [<ffffffff813af269>] ? ___sys_sendmsg+0x359/0x370
[   87.841212]  [<ffffffff813da686>] ? dev_ioctl+0x1a6/0x5c0
[   87.841236]  [<ffffffff8109c210>] ? autoremove_wake_function+0x30/0x30
[   87.841264]  [<ffffffff813ac59d>] ? sock_do_ioctl+0x3d/0x50
[   87.841288]  [<ffffffff813aca68>] ? sock_ioctl+0x1e8/0x2c0
[   87.841312]  [<ffffffff811934bf>] ? do_vfs_ioctl+0x2cf/0x4b0
[   87.841335]  [<ffffffff813afeb9>] ? __sys_sendmsg+0x39/0x70
[   87.841362]  [<ffffffff814b86f9>] ? system_call_fastpath+0x16/0x1b
[   87.841386] Code: c0 74 10 48 89 ef ff d0 83 c0 07 83 e0 fc 48 98 49 01 c7 48 89 ef e8 d0 d6 fe ff 48 85 c0 0f 84 df 00 00 00 48 8b 90 08 07 00 00 <48> 8b 8a a8 00 00 00 31 d2 48 85 c9 74 0c 48 89 ee 48 89 c7 ff
[   87.841529] RIP  [<ffffffff813d47c0>] if_nlmsg_size+0xf0/0x220
[   87.841555]  RSP <ffff880221aa5950>
[   87.841569] CR2: 00000000000000a8
[   87.851442] ---[ end trace e42ab217691b4fc2 ]---
Signed-off-by: NFernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
Acked-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This check is not needed because the same check is done before
fill_slave_info is used in rtnl_link_slave_info_fill.
Also, by removing this check, kernel will fillup IFLA_INFO_SLAVE_KIND
even for slaves of masters which does not implement fill_slave_info.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Recent patch
bonding: add netlink attributes to slave link dev (1d3ee88a)

Introduced yet another device specific way to access slave information
over rtnetlink. There is one already there for bridge.

This patch introduces generic way to do this, for getting and setting
info as well by extending link_ops. Later on, this new interface will
be used for bridge ports as well.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Acked-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If link is IFF_SLAVE, extend link dev netlink attributes to include
slave attributes with new IFLA_SLAVE nest.  Add netlink notification
(RTM_NEWLINK) when slave status changes from backup to active, or
visa-versa.

Adds new ndo_get_slave op to net_device_ops to fill skb with IFLA_SLAVE
attributes.  Currently only used by bonding driver, but could be
used by other aggregating devices with slaves.
Signed-off-by: NScott Feldman <sfeldma@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The function __rtnl_af_register is never called outside this
code, and the return value is always 0.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 991fb3f7 "dev: always advertise rx_flags changes via netlink"
introduced rtnl notification from __dev_set_promiscuity(),
which can be called in atomic context.

Steps to reproduce:
ip tuntap add dev tap1 mode tap
ifconfig tap1 up
tcpdump -nei tap1 &
ip tuntap del dev tap1 mode tap

[  271.627994] device tap1 left promiscuous mode
[  271.639897] BUG: sleeping function called from invalid context at mm/slub.c:940
[  271.664491] in_atomic(): 1, irqs_disabled(): 0, pid: 3394, name: ip
[  271.677525] INFO: lockdep is turned off.
[  271.690503] CPU: 0 PID: 3394 Comm: ip Tainted: G        W    3.12.0-rc3+ #73
[  271.703996] Hardware name: System manufacturer System Product Name/P8Z77 WS, BIOS 3007 07/26/2012
[  271.731254]  ffffffff81a58506 ffff8807f0d57a58 ffffffff817544e5 ffff88082fa0f428
[  271.760261]  ffff8808071f5f40 ffff8807f0d57a88 ffffffff8108bad1 ffffffff81110ff8
[  271.790683]  0000000000000010 00000000000000d0 00000000000000d0 ffff8807f0d57af8
[  271.822332] Call Trace:
[  271.838234]  [<ffffffff817544e5>] dump_stack+0x55/0x76
[  271.854446]  [<ffffffff8108bad1>] __might_sleep+0x181/0x240
[  271.870836]  [<ffffffff81110ff8>] ? rcu_irq_exit+0x68/0xb0
[  271.887076]  [<ffffffff811a80be>] kmem_cache_alloc_node+0x4e/0x2a0
[  271.903368]  [<ffffffff810b4ddc>] ? vprintk_emit+0x1dc/0x5a0
[  271.919716]  [<ffffffff81614d67>] ? __alloc_skb+0x57/0x2a0
[  271.936088]  [<ffffffff810b4de0>] ? vprintk_emit+0x1e0/0x5a0
[  271.952504]  [<ffffffff81614d67>] __alloc_skb+0x57/0x2a0
[  271.968902]  [<ffffffff8163a0b2>] rtmsg_ifinfo+0x52/0x100
[  271.985302]  [<ffffffff8162ac6d>] __dev_notify_flags+0xad/0xc0
[  272.001642]  [<ffffffff8162ad0c>] __dev_set_promiscuity+0x8c/0x1c0
[  272.017917]  [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380
[  272.033961]  [<ffffffff8162b109>] dev_set_promiscuity+0x29/0x50
[  272.049855]  [<ffffffff8172e937>] packet_dev_mc+0x87/0xc0
[  272.065494]  [<ffffffff81732052>] packet_notifier+0x1b2/0x380
[  272.080915]  [<ffffffff81731ea5>] ? packet_notifier+0x5/0x380
[  272.096009]  [<ffffffff81761c66>] notifier_call_chain+0x66/0x150
[  272.110803]  [<ffffffff8108503e>] __raw_notifier_call_chain+0xe/0x10
[  272.125468]  [<ffffffff81085056>] raw_notifier_call_chain+0x16/0x20
[  272.139984]  [<ffffffff81620190>] call_netdevice_notifiers_info+0x40/0x70
[  272.154523]  [<ffffffff816201d6>] call_netdevice_notifiers+0x16/0x20
[  272.168552]  [<ffffffff816224c5>] rollback_registered_many+0x145/0x240
[  272.182263]  [<ffffffff81622641>] rollback_registered+0x31/0x40
[  272.195369]  [<ffffffff816229c8>] unregister_netdevice_queue+0x58/0x90
[  272.208230]  [<ffffffff81547ca0>] __tun_detach+0x140/0x340
[  272.220686]  [<ffffffff81547ed6>] tun_chr_close+0x36/0x60
Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com>
Acked-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch only prepares the next one, there is no functional change.
Now, __dev_notify_flags() can also be used to notify flags changes via
rtnetlink.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>