This patch adds the following structure:

struct netlink_kernel_cfg {
        unsigned int    groups;
        void            (*input)(struct sk_buff *skb);
        struct mutex    *cb_mutex;
};

That can be passed to netlink_kernel_create to set optional configurations
for netlink kernel sockets.

I've populated this structure by looking for NULL and zero parameters at the
existing code. The remaining parameters that always need to be set are still
left in the original interface.

That includes optional parameters for the netlink socket creation. This allows
easy extensibility of this interface in the future.

This patch also adapts all callers to use this new interface.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Removes all RTA_GET*() and RTA_PUT*() variations, as well as the
the unused rtattr_strcmp(). Get rid of rtm_get_table() by moving
it to its only user decnet.
Signed-off-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Standardize the net core ratelimited logging functions.

Coalesce formats, align arguments.
Change a printk then vprintk sequence to use printf extension %pV.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is useful to be able to monitor for FDB events in user space.
This patch adds support to generate netlink events when a change
is made to a device supporting the FDB ops.

This brings embedded switches inline with the SW net/bridge which
triggers events on FDB updates as well.
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This adds a generic dump routine drivers can call. It
should be sufficient to handle any bridging model that
uses the unicast address list. This should be most SR-IOV
enabled NICs.

v2: return error on nlmsg_put and use -EMSGSIZE instead
    of -ENOMEM this is inline other usages
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This adds two new flags NTF_MASTER and NTF_SELF that can
now be used to specify where PF_BRIDGE netlink commands should
be sent. NTF_MASTER sends the commands to the 'dev->master'
device for parsing. Typically this will be the linux net/bridge,
or open-vswitch devices. Also without any flags set the command
will be handled by the master device as well so that current user
space tools continue to work as expected.

The NTF_SELF flag will push the PF_BRIDGE commands to the
device. In the basic example below the commands are then parsed
and programmed in the embedded bridge.

Note if both NTF_SELF and NTF_MASTER bits are set then the
command will be sent to both 'dev->master' and 'dev' this allows
user space to easily keep the embedded bridge and software bridge
in sync.

There is a slight complication in the case with both flags set
when an error occurs. To resolve this the rtnl handler clears
the NTF_ flag in the netlink ack to indicate which sets completed
successfully. The add/del handlers will abort as soon as any
error occurs.

To support this new net device ops were added to call into
the device and the existing bridging code was refactored
to use these. There should be no required changes in user space
to support the current bridge behavior.

A basic setup with a SR-IOV enabled NIC looks like this,

          veth0  veth2
            |      |
          ------------
          |  bridge0 |   <---- software bridging
          ------------
               /
               /
  ethx.y      ethx
    VF         PF
     \         \          <---- propagate FDB entries to HW
     \         \
  --------------------
  |  Embedded Bridge |    <---- hardware offloaded switching
  --------------------

In this case the embedded bridge must be managed to allow 'veth0'
to communicate with 'ethx.y' correctly. At present drivers managing
the embedded bridge either send frames onto the network which
then get dropped by the switch OR the embedded bridge will flood
these frames. With this patch we have a mechanism to manage the
embedded bridge correctly from user space. This example is specific
to SR-IOV but replacing the VF with another PF or dropping this
into the DSA framework generates similar management issues.

Examples session using the 'br'[1] tool to add, dump and then
delete a mac address with a new "embedded" option and enabled
ixgbe driver:

# br fdb add 22:35:19:ac:60:59 dev eth3
# br fdb
port    mac addr                flags
veth0   22:35:19:ac:60:58       static
veth0   9a:5f:81:f7:f6:ec       local
eth3    00:1b:21:55:23:59       local
eth3    22:35:19:ac:60:59       static
veth0   22:35:19:ac:60:57       static
#br fdb add 22:35:19:ac:60:59 embedded dev eth3
#br fdb
port    mac addr                flags
veth0   22:35:19:ac:60:58       static
veth0   9a:5f:81:f7:f6:ec       local
eth3    00:1b:21:55:23:59       local
eth3    22:35:19:ac:60:59       static
veth0   22:35:19:ac:60:57       static
eth3    22:35:19:ac:60:59       local embedded
#br fdb del 22:35:19:ac:60:59 embedded dev eth3

I added a couple lines to 'br' to set the flags correctly is all. It
is my opinion that the merit of this patch is now embedded and SW
bridges can both be modeled correctly in user space using very nearly
the same message passing.

[1] 'br' tool was published as an RFC here and will be renamed 'bridge'
    http://patchwork.ozlabs.org/patch/117664/

Thanks to Jamal Hadi Salim, Stephen Hemminger and Ben Hutchings for
valuable feedback, suggestions, and review.

v2: fixed api descriptions and error case with both NTF_SELF and
    NTF_MASTER set plus updated patch description.
Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use of "unsigned int" is preferred to bare "unsigned" in net tree.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Change get_tx_queues, drop unsused arg/return value real_tx_queues,
and use return by value (with error) rather than call by reference.

Probably bonding should just change to LLTX and the whole get_tx_queues
API could disappear!
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The standard ways of probing a device's promiscuity
(ifi_flags, for instance) does not report the actual
state of the device.  This patch adds dev->promiscuity
to the netlink netdevice report so that users can know
for certain if the device is acting PROMISC or not.
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: NDavid Howells <dhowells@redhat.com>

nlmsg_parse() might return an error, so test its return value before
potential random memory accesses.

Errors introduced in commit 115c9b81 (rtnetlink: Fix problem with
buffer allocation)
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add VF spoof check to IFLA policy.  The original patch I submitted to
add the spoof checking feature to rtnl failed to add the proper policy
rule that identifies the data type and len.  This patch corrects that
oversight.  No bugs have been reported against this but it may cause
some problem for the netlink message parsing that uses the policy
table.

CC: stable@vger.kernel.org
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Tested-by: NSibai Li <sibai.li@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Davem considers that the argument list of this interface is getting
out of control. This patch tries to address this issue following
his proposal:

struct netlink_dump_control c = { .dump = dump, .done = done, ... };

netlink_dump_start(..., &c);

Suggested by David S. Miller.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Implement a new netlink attribute type IFLA_EXT_MASK.  The mask
is a 32 bit value that can be used to indicate to the kernel that
certain extended ifinfo values are requested by the user application.
At this time the only mask value defined is RTEXT_FILTER_VF to
indicate that the user wants the ifinfo dump to send information
about the VFs belonging to the interface.

This patch fixes a bug in which certain applications do not have
large enough buffers to accommodate the extra information returned
by the kernel with large numbers of SR-IOV virtual functions.
Those applications will not send the new netlink attribute with
the interface info dump request netlink messages so they will
not get unexpectedly large request buffers returned by the kernel.

Modifies the rtnl_calcit function to traverse the list of net
devices and compute the minimum buffer size that can hold the
info dumps of all matching devices based upon the filter passed
in via the new netlink attribute filter mask.  If no filter
mask is sent then the buffer allocation defaults to NLMSG_GOODSIZE.

With this change it is possible to add yet to be defined netlink
attributes to the dump request which should make it fairly extensible
in the future.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Setting link parameters on a netdevice changes the value
of if_nlmsg_size(), therefore it is necessary to recalculate
min_ifinfo_dump_size.
Signed-off-by: NStefan Gula <steweg@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Once upon a time netlink was not sync and we had to get the effective
capabilities from the skb that was being received.  Today we instead get
the capabilities from the current task.  This has rendered the entire
purpose of the hook moot as it is now functionally equivalent to the
capable() call.
Signed-off-by: NEric Paris <eparis@redhat.com>

Before adding a struct rtnl_link_ops into link_ops list, check it doesnt
clash with a prior one.

Based on a previous patch from Alexander Smirnov
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
CC: Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add configuration setting for drivers to turn spoof checking on or off
for discrete VFs.

v2 - Fix indentation problem, wrap the ifla_vf_info structure in
     #ifdef __KERNEL__ to prevent user space from accessing and
     change function paramater for the spoof check setting netdev
     op from u8 to bool.
v3 - Preset spoof check setting to -1 so that user space tools such
     as ip can detect that the driver didn't report a spoofcheck
     setting.  Prevents incorrect display of spoof check settings
     for drivers that don't report it.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

dev->real_num_tx_queues is correctly set already in alloc_netdev_mqs.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds a change sequence counter to each net namespace
which is bumped whenever a netdevice is added or removed from
the list. If such a change occurred while a link dump took place,
the dump will have the NLM_F_DUMP_INTR flag set in the first
message which has been interrupted and in all subsequent messages
of the same dump.

Note that links may still be modified or renamed while a dump is
taking place but we can guarantee for userspace to receive a
complete list of links and not miss any.

Testing:
I have added 500 VLAN netdevices to make sure the dump is split
over multiple messages. Then while continuously dumping links in
one process I also continuously deleted and re-added a dummy
netdevice in another process. Multiple dumps per seconds have
had the NLM_F_DUMP_INTR flag set.

I guess we can wait for Johannes patch to hit net-next via the
wireless tree.  I just wanted to give this some testing right away.
Signed-off-by: NThomas Graf <tgraf@infradead.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The message size allocated for rtnl ifinfo dumps was limited to
a single page.  This is not enough for additional interface info
available with devices that support SR-IOV and caused a bug in
which VF info would not be displayed if more than approximately
40 VFs were created per interface.

Implement a new function pointer for the rtnl_register service that will
calculate the amount of data required for the ifinfo dump and allocate
enough data to satisfy the request.
Signed-off-by: NGreg Rose <gregory.v.rose@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

Commit e67f88dd (dont hold rtnl mutex during netlink dump callbacks)
missed fact that rtnl_fill_ifinfo() must be called with rtnl held.

Because of possible deadlocks between two mutexes (cb_mutex and rtnl),
its not easy to solve this problem, so revert this part of the patch.

It also forgot one rcu_read_unlock() in FIB dump_rules()

Add one ASSERT_RTNL() in rtnl_fill_ifinfo() to remind us the rule.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
CC: Patrick McHardy <kaber@trash.net>
CC: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These two events are not expected to be caught by userspace.
Signed-off-by: NWANG Cong <amwang@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Take advantage of the new abstraction and allow network devices
to be placed in any network namespace that we have a fd to talk
about.
Acked-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NDaniel Lezcano <daniel.lezcano@free.fr>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

veth devices dont use the batched device unregisters yet.

Since veth are a pair of devices, it makes sense to use a batch of two
unregisters, this roughly divides dismantle time by two.

Fix this by changing dellink() callers to always provide a non NULL
head. (Idea from Michał Mirosław)

This patch also handles macvlan case : We now dismantle all macvlans on
top of a lower dev at once.
Reported-by: NAlex Bligh <alex@alex.org.uk>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Michał Mirosław <mirqus@gmail.com>
Cc: Jesse Gross <jesse@nicira.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ben Greear <greearb@candelatech.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Force dev_alloc_name() to be called from register_netdevice() by
dev_get_valid_name(). That allows to remove multiple explicit
dev_alloc_name() calls.

The possibility to call dev_alloc_name in advance remains.

This also fixes veth creation regresion caused by
84c49d8cSigned-off-by: NJiri Pirko <jpirko@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Four years ago, Patrick made a change to hold rtnl mutex during netlink
dump callbacks.

I believe it was a wrong move. This slows down concurrent dumps, making
good old /proc/net/ files faster than rtnetlink in some situations.

This occurred to me because one "ip link show dev ..." was _very_ slow
on a workload adding/removing network devices in background.

All dump callbacks are able to use RCU locking now, so this patch does
roughly a revert of commits :

1c2d670f : [RTNETLINK]: Hold rtnl_mutex during netlink dump callbacks
6313c1e0 : [RTNETLINK]: Remove unnecessary locking in dump callbacks

This let writers fight for rtnl mutex and readers going full speed.

It also takes care of phonet : phonet_route_get() is now called from rcu
read section. I renamed it to phonet_route_get_rcu()
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
Acked-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

This patch allows userspace to enslave/release slave devices via netlink
interface using IFLA_MASTER. This introduces generic way to add/remove
underling devices.
Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Acked-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ed Swierk <eswierk@bigswitch.com> writes:
> On 2.6.35.7
>  ip link add link eth0 netns 9999 type macvlan
> where 9999 is a nonexistent PID triggers an oops and causes all network functions to hang:
> [10663.821898] BUG: unable to handle kernel NULL pointer dereference at 000000000000006d
>  [10663.821917] IP: [<ffffffff8149c2fa>] __dev_alloc_name+0x9a/0x170
>  [10663.821933] PGD 1d3927067 PUD 22f5c5067 PMD 0
>  [10663.821944] Oops: 0000 [#1] SMP
>  [10663.821953] last sysfs file: /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
>  [10663.821959] CPU 3
>  [10663.821963] Modules linked in: macvlan ip6table_filter ip6_tables rfcomm ipt_MASQUERADE binfmt_misc iptable_nat nf_nat nf_conntrack_ipv4 nf_defrag_ipv4 xt_state nf_conntrack sco ipt_REJECT bnep l2cap xt_tcpudp iptable_filter ip_tables x_tables bridge stp vboxnetadp vboxnetflt vboxdrv kvm_intel kvm parport_pc ppdev snd_hda_codec_intelhdmi snd_hda_codec_conexant arc4 iwlagn iwlcore mac80211 snd_hda_intel snd_hda_codec snd_hwdep snd_pcm snd_seq_midi snd_rawmidi i915 snd_seq_midi_event snd_seq thinkpad_acpi drm_kms_helper btusb tpm_tis nvram uvcvideo snd_timer snd_seq_device bluetooth videodev v4l1_compat v4l2_compat_ioctl32 tpm drm tpm_bios snd cfg80211 psmouse serio_raw intel_ips soundcore snd_page_alloc intel_agp i2c_algo_bit video output netconsole configfs lp parport usbhid hid e1000e sdhci_pci ahci libahci sdhci led_class
>  [10663.822155]
>  [10663.822161] Pid: 6000, comm: ip Not tainted 2.6.35-23-generic #41-Ubuntu 2901CTO/2901CTO
>  [10663.822167] RIP: 0010:[<ffffffff8149c2fa>] [<ffffffff8149c2fa>] __dev_alloc_name+0x9a/0x170
>  [10663.822177] RSP: 0018:ffff88014aebf7b8 EFLAGS: 00010286
>  [10663.822182] RAX: 00000000fffffff4 RBX: ffff8801ad900800 RCX: 0000000000000000
>  [10663.822187] RDX: ffff880000000000 RSI: 0000000000000000 RDI: ffff88014ad63000
>  [10663.822191] RBP: ffff88014aebf808 R08: 0000000000000041 R09: 0000000000000041
>  [10663.822196] R10: 0000000000000000 R11: dead000000200200 R12: ffff88014aebf818
>  [10663.822201] R13: fffffffffffffffd R14: ffff88014aebf918 R15: ffff88014ad62000
>  [10663.822207] FS: 00007f00c487f700(0000) GS:ffff880001f80000(0000) knlGS:0000000000000000
>  [10663.822212] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>  [10663.822216] CR2: 000000000000006d CR3: 0000000231f19000 CR4: 00000000000026e0
>  [10663.822221] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
>  [10663.822226] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
>  [10663.822231] Process ip (pid: 6000, threadinfo ffff88014aebe000, task ffff88014afb16e0)
>  [10663.822236] Stack:
>  [10663.822240] ffff88014aebf808 ffffffff814a2bb5 ffff88014aebf7e8 00000000a00ee8d6
>  [10663.822251] <0> 0000000000000000 ffffffffa00ef940 ffff8801ad900800 ffff88014aebf818
>  [10663.822265] <0> ffff88014aebf918 ffff8801ad900800 ffff88014aebf858 ffffffff8149c413
>  [10663.822281] Call Trace:
>  [10663.822290] [<ffffffff814a2bb5>] ? dev_addr_init+0x75/0xb0
>  [10663.822298] [<ffffffff8149c413>] dev_alloc_name+0x43/0x90
>  [10663.822307] [<ffffffff814a85ee>] rtnl_create_link+0xbe/0x1b0
>  [10663.822314] [<ffffffff814ab2aa>] rtnl_newlink+0x48a/0x570
>  [10663.822321] [<ffffffff814aafcc>] ? rtnl_newlink+0x1ac/0x570
>  [10663.822332] [<ffffffff81030064>] ? native_x2apic_icr_read+0x4/0x20
>  [10663.822339] [<ffffffff814a8c17>] rtnetlink_rcv_msg+0x177/0x290
>  [10663.822346] [<ffffffff814a8aa0>] ? rtnetlink_rcv_msg+0x0/0x290
>  [10663.822354] [<ffffffff814c25d9>] netlink_rcv_skb+0xa9/0xd0
>  [10663.822360] [<ffffffff814a8a85>] rtnetlink_rcv+0x25/0x40
>  [10663.822367] [<ffffffff814c223e>] netlink_unicast+0x2de/0x2f0
>  [10663.822374] [<ffffffff814c303e>] netlink_sendmsg+0x1fe/0x2e0
>  [10663.822383] [<ffffffff81488533>] sock_sendmsg+0xf3/0x120
>  [10663.822391] [<ffffffff815899fe>] ? _raw_spin_lock+0xe/0x20
>  [10663.822400] [<ffffffff81168656>] ? __d_lookup+0x136/0x150
>  [10663.822406] [<ffffffff815899fe>] ? _raw_spin_lock+0xe/0x20
>  [10663.822414] [<ffffffff812b7a0d>] ? _atomic_dec_and_lock+0x4d/0x80
>  [10663.822422] [<ffffffff8116ea90>] ? mntput_no_expire+0x30/0x110
>  [10663.822429] [<ffffffff81486ff5>] ? move_addr_to_kernel+0x65/0x70
>  [10663.822435] [<ffffffff81493308>] ? verify_iovec+0x88/0xe0
>  [10663.822442] [<ffffffff81489020>] sys_sendmsg+0x240/0x3a0
> [10663.822450] [<ffffffff8111e2a9>] ? __do_fault+0x479/0x560
>  [10663.822457] [<ffffffff815899fe>] ? _raw_spin_lock+0xe/0x20
>  [10663.822465] [<ffffffff8116cf4a>] ? alloc_fd+0x10a/0x150
>  [10663.822473] [<ffffffff8158d76e>] ? do_page_fault+0x15e/0x350
>  [10663.822482] [<ffffffff8100a0f2>] system_call_fastpath+0x16/0x1b
>  [10663.822487] Code: 90 48 8d 78 02 be 25 00 00 00 e8 92 1d e2 ff 48 85 c0 75 cf bf 20 00 00 00 e8 c3 b1 c6 ff 49 89 c7 b8 f4 ff ff ff 4d 85 ff 74 bd <4d> 8b 75 70 49 8d 45 70 48 89 45 b8 49 83 ee 58 eb 28 48 8d 55
>  [10663.822618] RIP [<ffffffff8149c2fa>] __dev_alloc_name+0x9a/0x170
>  [10663.822627] RSP <ffff88014aebf7b8>
>  [10663.822631] CR2: 000000000000006d
>  [10663.822636] ---[ end trace 3dfd6c3ad5327ca7 ]---

This bug was introduced in:
commit 81adee47
Author: Eric W. Biederman <ebiederm@aristanetworks.com>
Date:   Sun Nov 8 00:53:51 2009 -0800

    net: Support specifying the network namespace upon device creation.

    There is no good reason to not support userspace specifying the
    network namespace during device creation, and it makes it easier
    to create a network device and pass it to a child network namespace
    with a well known name.

    We have to be careful to ensure that the target network namespace
    for the new device exists through the life of the call.  To keep
    that logic clear I have factored out the network namespace grabbing
    logic into rtnl_link_get_net.

    In addtion we need to continue to pass the source network namespace
    to the rtnl_link_ops.newlink method so that we can find the base
    device source network namespace.
Signed-off-by: NEric W. Biederman <ebiederm@aristanetworks.com>
Acked-by: NEric Dumazet <eric.dumazet@gmail.com>

Where apparently I forgot to add error handling to the path where we create
a new network device in a new network namespace, and pass in an invalid pid.

Cc: stable@kernel.org
Reported-by: NEd Swierk <eswierk@bigswitch.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I'm testing an API that uses IFLA_AF_SPEC attribute.
In the rtnetlink core , the set_link_af() member
of the rtnl_af_ops struct receives the nested attribute
(as I expected), but the validate_link_af() member
receives the parent attribute.
IMO, this patch fixes this.
Signed-off-by: NKurt Van Dijck <kurt.van.dijck@eia.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

rtnl_group_changelink() is invoked by rtnl_newlink() before the link
attributes have been validated. Additionally the group changes are
performed even if NLM_F_CREATE is specified and a new link is
created, while more reasonable semantics would be to set the group
value on the newly created link.

Fix both problems by moving the rtnl_group_changelink() invocation
down to the handling of non-existant links without NLM_F_CREATE()
and add a dev_set_group() call to rtnl_create_link().
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Acked-by: NVlad Dogaru <ddvlad@rosedu.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If a rtnetlink request specifies a negative or zero ifindex and has no
interface name attribute, but has a group attribute, then the chenges
are made to all the interfaces belonging to the specified group.
Signed-off-by: NVlad Dogaru <ddvlad@rosedu.org>
Acked-by: NJamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Net devices can now be grouped, enabling simpler manipulation from
userspace. This patch adds a group field to the net_device structure, as
well as rtnetlink support to query and modify it.
Signed-off-by: NVlad Dogaru <ddvlad@rosedu.org>
Acked-by: NJamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This reverts commit 0ab03c2b.

It breaks several things including the avahi daemon.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Due to NLM_F_DUMP is composed of two bits, NLM_F_ROOT | NLM_F_MATCH,
when doing "if (x & NLM_F_DUMP)", it tests for _either_ of the bits
being set. Because NLM_F_MATCH's value overlaps with NLM_F_EXCL,
non-dump requests with NLM_F_EXCL set are mistaken as dump requests.

Substitute the condition to test for _all_ bits being set.
Signed-off-by: NJan Engelhardt <jengelh@medozas.de>
Acked-by: NPablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As David pointed out correctly, updates to af-specific attributes
are currently not atomic. If multiple changes are requested and
one of them fails, previous updates may have been applied already
leaving the link behind in a undefined state.

This patch splits the function parse_link_af() into two functions
validate_link_af() and set_link_at(). validate_link_af() is placed
to validate_linkmsg() check for errors as early as possible before
any changes to the link have been made. set_link_af() is called to
commit the changes later.

This method is not fail proof, while it is currently sufficient
to make set_link_af() inerrable and thus 100% atomic, the
validation function method will not be able to detect all error
scenarios in the future, there will likely always be errors
depending on states which are f.e. not protected by rtnl_mutex
and thus may change between validation and setting.

Also, instead of silently ignoring unknown address families and
config blocks for address families which did not register a set
function the errors EAFNOSUPPORT respectively EOPNOSUPPORT are
returned to avoid comitting 4 out of 5 update requests without
notifying the user.
Signed-off-by: NThomas Graf <tgraf@infradead.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Each net_device contains address family specific data such as
per device settings and statistics. We already expose this data
via procfs/sysfs and partially netlink.

The netlink method requires the requester to send one RTM_GETLINK
request for each address family it wishes to receive data of
and then merge this data itself.

This patch implements a new API which combines all address family
specific link data in a new netlink attribute IFLA_AF_SPEC.
IFLA_AF_SPEC contains a sequence of nested attributes, one for each
address family which in turn defines the structure of its own
attribute. Example:

   [IFLA_AF_SPEC] = {
       [AF_INET] = {
           [IFLA_INET_CONF] = ...,
       },
       [AF_INET6] = {
           [IFLA_INET6_FLAGS] = ...,
           [IFLA_INET6_CONF] = ...,
       }
   }

The API also allows for address families to implement a function
which parses the IFLA_AF_SPEC attribute sent by userspace to
implement address family specific link options.
Signed-off-by: NThomas Graf <tgraf@infradead.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

nlmsg_total_size() calculates the length of a netlink message
including header and alignment. nla_total_size() calculates the
space an individual attribute consumes which was meant to be used
in this context.

Also, ensure to account for the attribute header for the
IFLA_INFO_XSTATS attribute as implementations of get_xstats_size()
seem to assume that we do so.

The addition of two message headers minus the missing attribute
header resulted in a calculated message size that was larger than
required. Therefore we never risked running out of skb tailroom.
Signed-off-by: NThomas Graf <tgraf@infradead.org>
Acked-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>