rtnetlink: add RTNL_FLAG_DUMP_UNLOCKED flag

Similarly to RTNL_FLAG_DOIT_UNLOCKED, this new flag
allows dump operations registered via rtnl_register()
or rtnl_register_module() to opt-out from RTNL protection.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Donald Hunter <donald.hunter@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: validate veth and vxcan peer ifindexes

veth and vxcan need to make sure the ifindexes of the peer
are not negative, core does not validate this.

Using iproute2 with user-space-level checking removed:

Before:

# ./ip link add index 10 type veth peer index -1
# ip link show
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enp1s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000
link/ether 52:54:00:74:b2:03 brd ff:ff:ff:ff:ff:ff
10: veth1@veth0: <BROADCAST,MULTICAST,M-DOWN> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether 8a:90:ff:57:6d:5d brd ff:ff:ff:ff:ff:ff
-1: veth0@veth1: <BROADCAST,MULTICAST,M-DOWN> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
link/ether ae:ed:18:e6:fa:7f brd ff:ff:ff:ff:ff:ff

Now:

$ ./ip link add index 10 type veth peer index -1
Error: ifindex can't be negative.

This problem surfaced in net-next because an explicit WARN()
was added, the root cause is older.

Fixes: e6f8f1a739b6 ("veth: Allow to create peer link with given ifindex")
Fixes: a8f820a380a2 ("can: add Virtual CAN Tunnel driver (vxcan)")
Reported-by: syzbot+5ba06978f34abb058571@syzkaller.appspotmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: Honour NLM_F_ECHO flag in rtnl_delete_link

This patch use the new helper unregister_netdevice_many_notify() for
rtnl_delete_link(), so that the kernel could reply unicast when userspace
set NLM_F_ECHO flag to request the new created interface info.

At the same time, the parameters of rtnl_delete_link() need to be updated
since we need nlmsghdr and portid info.

Suggested-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

rtnetlink: pass netlink message header and portid to rtnl_configure_link()

This patch pass netlink message header and portid to rtnl_configure_link()
All the functions in this call chain need to add the parameters so we can
use them in the last call rtnl_notify(), and notify the userspace about
the new link info if NLM_F_ECHO flag is set.

- rtnl_configure_link()
- __dev_notify_flags()
- rtmsg_ifinfo()
- rtmsg_ifinfo_event()
- rtmsg_ifinfo_build_skb()
- rtmsg_ifinfo_send()
- rtnl_notify()

Also move __dev_notify_flags() declaration to net/core/dev.h, as Jakub
suggested.

Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: rtnetlink: add bulk delete support flag

Add a new rtnl flag (RTNL_FLAG_BULK_DEL_SUPPORTED) which is used to
verify that the delete operation allows bulk object deletion. Also emit
a warning if anyone tries to set it for non-delete kind.

Suggested-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rtnetlink: use BIT for flag values

Use BIT to define flag values.

Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rtnetlink: add helper to extract msg type's kind

Add a helper which extracts the msg type's kind using the kind mask (0x3).

Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rtnetlink: add msg kind names

Add rtnl kind names instead of using raw values. We'll need to
check for DEL kind later to validate bulk flag support.

Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: add extack arg for link ops

Pass extack arg to validate_linkmsg and validate_link_af callbacks.
If a netlink attribute has a reject_message, use the extended ack
mechanism to carry the message back to user space.

Signed-off-by: Rocco Yue <rocco.yue@mediatek.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: add alloc() method to rtnl_link_ops

In order to make rtnetlink ops that can create different
kinds of devices, like what we want to add to the WWAN
framework, the priv_size and setup parameters aren't quite
sufficient. Make this easier to manage by allowing ops to
allocate their own netdev via an @alloc method that gets
the tb netlink data.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

ipv6: report errors for iftoken via netlink extack

Setting iftoken can fail for several different reasons but there
and there was no report to user as to the cause. Add netlink
extended errors to the processing of the request.

This requires adding additional argument through rtnl_af_ops
set_link_af callback.

Reported-by: Hongren Zheng <li@zenithal.me>
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

can: dev: Move device back to init netns on owning netns delete

When a non-initial netns is destroyed, the usual policy is to delete
all virtual network interfaces contained, but move physical interfaces
back to the initial netns. This keeps the physical interface visible
on the system.

CAN devices are somewhat special, as they define rtnl_link_ops even
if they are physical devices. If a CAN interface is moved into a
non-initial netns, destroying that netns lets the interface vanish
instead of moving it back to the initial netns. default_device_exit()
skips CAN interfaces due to having rtnl_link_ops set. Reproducer:

ip netns add foo
ip link set can0 netns foo
ip netns delete foo

WARNING: CPU: 1 PID: 84 at net/core/dev.c:11030 ops_exit_list+0x38/0x60
CPU: 1 PID: 84 Comm: kworker/u4:2 Not tainted 5.10.19 #1
Workqueue: netns cleanup_net
[<c010e700>] (unwind_backtrace) from [<c010a1d8>] (show_stack+0x10/0x14)
[<c010a1d8>] (show_stack) from [<c086dc10>] (dump_stack+0x94/0xa8)
[<c086dc10>] (dump_stack) from [<c086b938>] (__warn+0xb8/0x114)
[<c086b938>] (__warn) from [<c086ba10>] (warn_slowpath_fmt+0x7c/0xac)
[<c086ba10>] (warn_slowpath_fmt) from [<c0629f20>] (ops_exit_list+0x38/0x60)
[<c0629f20>] (ops_exit_list) from [<c062a5c4>] (cleanup_net+0x230/0x380)
[<c062a5c4>] (cleanup_net) from [<c0142c20>] (process_one_work+0x1d8/0x438)
[<c0142c20>] (process_one_work) from [<c0142ee4>] (worker_thread+0x64/0x5a8)
[<c0142ee4>] (worker_thread) from [<c0148a98>] (kthread+0x148/0x14c)
[<c0148a98>] (kthread) from [<c0100148>] (ret_from_fork+0x14/0x2c)

To properly restore physical CAN devices to the initial netns on owning
netns exit, introduce a flag on rtnl_link_ops that can be set by drivers.
For CAN devices setting this flag, default_device_exit() considers them
non-virtual, applying the usual namespace move.

The issue was introduced in the commit mentioned below, as at that time
CAN devices did not have a dellink() operation.

Fixes: e008b5fc8dc7 ("net: Simplfy default_device_exit and improve batching.")
Link: https://lore.kernel.org/r/20210302122423.872326-1-martin@strongswan.org
Signed-off-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

net: Add extack argument to rtnl_create_link

Add extack arg to rtnl_create_link and add messages for invalid
number of Tx or Rx queues.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: add rtnl_get_net_ns_capable()

get_target_net() will be used in follow-up patches in ipv{4,6} codepaths to
retrieve network namespaces based on network namespace identifiers. So
remove the static declaration and export in the rtnetlink header. Also,
rename it to rtnl_get_net_ns_capable() to make it obvious what this
function is doing.
Export rtnl_get_net_ns_capable() so it can be used when ipv6 is built as
a module.

Signed-off-by: Christian Brauner <christian@brauner.io>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: Remove VLA usage

In the quest to remove all stack VLA usage from the kernel[1], this
allocates the maximum size expected for all possible types and adds
sanity-checks at both registration and usage to make sure nothing gets
out of sync. This matches the proposed VLA solution for nfnetlink[2]. The
values chosen here were based on finding assignments for .maxtype and
.slave_maxtype and manually counting the enums:

slave_maxtype (max 33):
IFLA_BRPORT_MAX 33
IFLA_BOND_SLAVE_MAX 9

maxtype (max 45):
IFLA_BOND_MAX 28
IFLA_BR_MAX 45
__IFLA_CAIF_HSI_MAX 8
IFLA_CAIF_MAX 4
IFLA_CAN_MAX 16
IFLA_GENEVE_MAX 12
IFLA_GRE_MAX 25
IFLA_GTP_MAX 5
IFLA_HSR_MAX 7
IFLA_IPOIB_MAX 4
IFLA_IPTUN_MAX 21
IFLA_IPVLAN_MAX 3
IFLA_MACSEC_MAX 15
IFLA_MACVLAN_MAX 7
IFLA_PPP_MAX 2
__IFLA_RMNET_MAX 4
IFLA_VLAN_MAX 6
IFLA_VRF_MAX 2
IFLA_VTI_MAX 7
IFLA_VXLAN_MAX 28
VETH_INFO_MAX 2
VXCAN_INFO_MAX 2

This additionally changes maxtype and slave_maxtype fields to unsigned,
since they're only ever using positive values.

[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
[2] https://patchwork.kernel.org/patch/10439647/

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: remove __rtnl_register

This removes __rtnl_register and switches callers to either
rtnl_register or rtnl_register_module.

Also, rtnl_register() will now print an error if memory allocation
failed rather than panic the kernel.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: get reference on module before invoking handlers

Add yet another rtnl_register function. It will be used by modules
that can be removed.

The passed module struct is used to prevent module unload while
a netlink dump is in progress or when a DOIT_UNLOCKED doit callback
is called.

Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

rtnetlink: remove __rtnl_af_unregister

switch the only caller to rtnl_af_unregister.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: remove slave_validate callback

no users in the tree.

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: add RTNL_FLAG_DOIT_UNLOCKED

Allow callers to tell rtnetlink core that its doit callback
should be invoked without holding rtnl mutex.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: make rtnl_register accept a flags parameter

This change allows us to later indicate to rtnetlink core that certain
doit functions should be called without acquiring rtnl_mutex.

This change should have no effect, we simply replace the last (now
unused) calcit argument with the new flag.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: add netlink_ext_ack argument to rtnl_link_ops.slave_validate

Add support for extended error reporting.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: add netlink_ext_ack argument to rtnl_link_ops.slave_changelink

Add support for extended error reporting.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: add netlink_ext_ack argument to rtnl_link_ops.validate

Add support for extended error reporting.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: add netlink_ext_ack argument to rtnl_link_ops.changelink

Add support for extended error reporting.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: add netlink_ext_ack argument to rtnl_link_ops.newlink

Add support for extended error reporting.

Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rtnetlink: plumb extended ack to doit function

Add netlink_ext_ack arg to rtnl_doit_func. Pass extack arg to nlmsg_parse
for doit functions that call it directly.

This is the first step to using extended error reporting in rtnetlink.
>From here individual subsystems can be updated to set netlink_ext_ack as
needed.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netlink: pass extended ACK struct to parsing functions

Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: AF-specific RTM_GETSTATS attributes

Add the functionality for including address-family-specific per-link
stats in RTM_GETSTATS messages. This is done through adding a new
IFLA_STATS_AF_SPEC attribute under which address family attributes are
nested and then the AF-specific attributes can be further nested. This
follows the model of IFLA_AF_SPEC on RTM_*LINK messages and it has the
advantage of presenting an easily extended hierarchy. The rtnl_af_ops
structure is extended to provide AFs with the opportunity to fill and
provide the size of their stats attributes.

One alternative would have been to provide AFs with the ability to add
attributes directly into the RTM_GETSTATS message without a nested
hierarchy. I discounted this approach as it increases the rate at
which the 32 attribute number space is used up and it makes
implementation a little more tricky for stats dump resuming (at the
moment the order in which attributes are added to the message has to
match the numeric order of the attributes).

Another alternative would have been to register per-AF RTM_GETSTATS
handlers. I discounted this approach as I perceived a common use-case
to be getting all the stats for an interface and this approach would
necessitate multiple requests/dumps to retrieve them all.

Signed-off-by: Robert Shearman <rshearma@brocade.com>
Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rtnetlink: add support for the IFLA_STATS_LINK_XSTATS_SLAVE attribute

This patch adds support for the IFLA_STATS_LINK_XSTATS_SLAVE attribute
which allows to export per-slave statistics if the master device supports
the linkxstats callback. The attribute is passed down to the linkxstats
callback and it is up to the callback user to use it (an example has been
added to the only current user - the bridge). This allows us to query only
specific slaves of master devices like bridge ports and export only what
we're interested in instead of having to dump all ports and searching only
for a single one. This will be used to export per-port IGMP/MLD stats and
also per-port vlan stats in the future, possibly other statistics as well.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rtnetlink: add linkxstats callbacks and attribute

Add callbacks to calculate the size and fill link extended statistics
which can be split into multiple messages and are dumped via the new
rtnl stats API (RTM_GETSTATS) with the IFLA_STATS_LINK_XSTATS attribute.
Also add that attribute to the idx mask check since it is expected to
be able to save state and resume dumping (e.g. future bridge per-vlan
stats will be dumped via this attribute and callbacks).
Each link type should nest its private attributes under the per-link type
attribute. This allows to have any number of separated private attributes
and to avoid one call to get the dev link type.

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netlink: Rightsize IFLA_AF_SPEC size calculation

if_nlmsg_size() overestimates the minimum allocation size of netlink
dump request (when called from rtnl_calcit()) or the size of the
message (when called from rtnl_getlink()). This is because
ext_filter_mask is not supported by rtnl_link_get_af_size() and
rtnl_link_get_size().

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

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

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

Signed-off-by: Ronen Arad <ronen.arad@intel.com>
Acked-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: RTEXT_FILTER_SKIP_STATS support to avoid dumping inet/inet6 stats

Many commonly used functions like getifaddrs() invoke RTM_GETLINK
to dump the interface information, and do not need the
the AF_INET6 statististics that are always returned by default
from rtnl_fill_ifinfo().

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

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

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

openvswitch: Use regular VXLAN net_device device

This gets rid of all OVS specific VXLAN code in the receive and
transmit path by using a VXLAN net_device to represent the vport.
Only a small shim layer remains which takes care of handling the
VXLAN specific OVS Netlink configuration.

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

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: Mark name argument of rtnl_create_link() const

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnl: add link netns id to interface messages

This patch adds a new attribute (IFLA_LINK_NETNSID) which contains the 'link'
netns id when this netns is different from the netns where the interface
stands (for example for x-net interfaces like ip tunnels).
With this attribute, it's possible to interpret correctly all advertised
information (like IFLA_LINK, etc.).

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rtnetlink - make create_link take name_assign_type

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: Tom Gundersen <teg@jklm.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnl: make ifla_policy static

The only place this is used outside rtnetlink.c is veth. So provide
wrapper function for this usage.

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

rtnetlink: provide api for getting and setting slave info

Recent patch
bonding: add netlink attributes to slave link dev (1d3ee88ae0d6)

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

netlink: cleanup rntl_af_register

The function __rtnl_af_register is never called outside this
code, and the return value is always 0.

Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink.h: Remove extern from function prototypes

There are a mix of function prototypes with and without extern
in the kernel sources. Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler. Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: Remove passing of attributes into rtnl_doit functions

With decnet converted, we can finally get rid of rta_buf and its
computations around it. It also gets rid of the minimal header
length verification since all message handlers do that explicitly
anyway.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnelink: remove unused parameter from rtnl_create_link().

This patch removes an unused parameter (src_net) from rtnl_create_link()
method and from the method single invocation, in veth.
This parameter was used in the past when calling
ops->get_tx_queues(src_net, tb) in rtnl_create_link().
The get_tx_queues() member of rtnl_link_ops was replaced by two methods,
get_num_tx_queues() and get_num_rx_queues(), which do not get any
parameter. This was done in commit d40156aa5ecbd51fed932ed4813df82b56e5ff4d by
Jiri Pirko ("rtnl: allow to specify different num for rx and tx queue count").

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnl: allow to specify different num for rx and tx queue count

Also cut out unused function parameters and possible err in return
value.

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

rtnetlink: ops->get_tx_queue() cannot take a const 'tb'.

net/core/rtnetlink.c: In function ‘rtnl_create_link’:
net/core/rtnetlink.c:1645:3: warning: passing argument 2 of ‘ops->get_tx_queues’ from incompatible pointer type [enabled by default]
net/core/rtnetlink.c:1645:3: note: expected ‘const struct nlattr **’ but argument is of type ‘struct nlattr **’

Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: fix comments

Fix spelling and references in rtnetlink.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink & bonding: change args got get_tx_queues

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: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: Fix problem with buffer allocation

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: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: Compute and store minimum ifinfo dump size

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: Greg Rose <gregory.v.rose@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

rtnl: make link af-specific updates atomic

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: Thomas Graf <tgraf@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: Link address family API

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: Thomas Graf <tgraf@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: remove rtnl_kill_links

The function rtnl_kill_links is defined but never used.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

rtnetlink: support specifying device flags on device creation

commit e8469ed959c373c2ff9e6f488aa5a14971aebe1f
Author: Patrick McHardy <kaber@trash.net>
Date: Tue Feb 23 20:41:30 2010 +0100

Support specifying the initial device flags when creating a device though
rtnl_link. Devices allocated by rtnl_create_link() are marked as INITIALIZING
in order to surpress netlink registration notifications. To complete setup,
rtnl_configure_link() must be called, which performs the device flag changes
and invokes the deferred notifiers if everything went well.

Two examples:

# add macvlan to eth0
#
$ ip link add link eth0 up allmulticast on type macvlan

[LINK]11: macvlan0@eth0: <BROADCAST,MULTICAST,ALLMULTI,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN
link/ether 26:f8:84:02:f9:2a brd ff:ff:ff:ff:ff:ff
[ROUTE]ff00::/8 dev macvlan0 table local metric 256 mtu 1500 advmss 1440 hoplimit 0
[ROUTE]fe80::/64 dev macvlan0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 0
[LINK]11: macvlan0@eth0: <BROADCAST,MULTICAST,ALLMULTI,UP,LOWER_UP> mtu 1500
link/ether 26:f8:84:02:f9:2a
[ADDR]11: macvlan0 inet6 fe80::24f8:84ff:fe02:f92a/64 scope link
valid_lft forever preferred_lft forever
[ROUTE]local fe80::24f8:84ff:fe02:f92a via :: dev lo table local proto none metric 0 mtu 16436 advmss 16376 hoplimit 0
[ROUTE]default via fe80::215:e9ff:fef0:10f8 dev macvlan0 proto kernel metric 1024 mtu 1500 advmss 1440 hoplimit 0
[NEIGH]fe80::215:e9ff:fef0:10f8 dev macvlan0 lladdr 00:15:e9:f0:10:f8 router STALE
[ROUTE]2001:6f8:974::/64 dev macvlan0 proto kernel metric 256 expires 0sec mtu 1500 advmss 1440 hoplimit 0
[PREFIX]prefix 2001:6f8:974::/64 dev macvlan0 onlink autoconf valid 14400 preferred 131084
[ADDR]11: macvlan0 inet6 2001:6f8:974:0:24f8:84ff:fe02:f92a/64 scope global dynamic
valid_lft 86399sec preferred_lft 14399sec

# add VLAN to eth1, eth1 is down
#
$ ip link add link eth1 up type vlan id 1000
RTNETLINK answers: Network is down

<no events>

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

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: Eric W. Biederman <ebiederm@aristanetworks.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>

net: add a list_head parameter to dellink() method

Adding a list_head parameter to rtnl_link_ops->dellink() methods
allow us to queue devices on a list, in order to dismantle
them all at once.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

vlan: multiqueue vlan device

vlan devices are currently not multi-queue capable.

We can do that with a new rtnl_link_ops method,
get_tx_queues(), called from rtnl_create_link()

This new method gets num_tx_queues/real_num_tx_queues
from real device.

register_vlan_device() is also handled.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netlink: constify nlmsghdr arguments

Consitfy nlmsghdr arguments to a couple of functions as preparation
for the next patch, which will constify the netlink message data in
all nfnetlink users.

Signed-off-by: Patrick McHardy <kaber@trash.net>

[RTNL]: Introduce the rtnl_kill_links helper.

This one is responsible for calling ->dellink on each net
device found in net to help with vlan net_exit hook in the
nearest future.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Make the device list and device lookups per namespace.

This patch makes most of the generic device layer network
namespace safe. This patch makes dev_base_head a
network namespace variable, and then it picks up
a few associated variables. The functions:
dev_getbyhwaddr
dev_getfirsthwbytype
dev_get_by_flags
dev_get_by_name
__dev_get_by_name
dev_get_by_index
__dev_get_by_index
dev_ioctl
dev_ethtool
dev_load
wireless_process_ioctl

were modified to take a network namespace argument, and
deal with it.

vlan_ioctl_set and brioctl_set were modified so their
hooks will receive a network namespace argument.

So basically anthing in the core of the network stack that was
affected to by the change of dev_base was modified to handle
multiple network namespaces. The rest of the network stack was
simply modified to explicitly use &init_net the initial network
namespace. This can be fixed when those components of the network
stack are modified to handle multiple network namespaces.

For now the ifindex generator is left global.

Fundametally ifindex numbers are per namespace, or else
we will have corner case problems with migration when
we get that far.

At the same time there are assumptions in the network stack
that the ifindex of a network device won't change. Making
the ifindex number global seems a good compromise until
the network stack can cope with ifindex changes when
you change namespaces, and the like.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[RTNETLINK]: Introduce generic rtnl_create_link().

This routine gets the parsed rtnl attributes and creates a new
link with generic info (IFLA_LINKINFO policy). Its intention
is to help the drivers, that need to create several links at
once (like VETH).

This is nothing but a copy-paste-ed part of rtnl_newlink() function
that is responsible for creation of new device.

Signed-off-by: Pavel Emelianov <xemul@openvz.org>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[RTNETLINK]: Link creation API

Add rtnetlink API for creating, changing and deleting software devices.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETLINK]: Possible cleanups.

- make the following needlessly global variables static:
- core/rtnetlink.c: struct rtnl_msg_handlers[]
- netfilter/nf_conntrack_proto.c: struct nf_ct_protos[]
- make the following needlessly global functions static:
- core/rtnetlink.c: rtnl_dump_all()
- netlink/af_netlink.c: netlink_queue_skip()

Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET] rules: Unified rules dumping

Implements a unified, protocol independant rules dumping function
which is capable of both, dumping a specific protocol family or
all of them. This speeds up dumping as less lookups are required.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

[RTNL]: Message handler registration interface

This patch adds a new interface to register rtnetlink message
handlers replacing the exported rtnl_links[] array which
required many message handlers to be exported unnecessarly.

Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>