RFC 8200 (IPv6) defines Hop-by-Hop options and Destination options
extension headers. Both of these carry a list of TLVs which is
only limited by the maximum length of the extension header (2048
bytes). By the spec a host must process all the TLVs in these
options, however these could be used as a fairly obvious
denial of service attack. I think this could in fact be
a significant DOS vector on the Internet, one mitigating
factor might be that many FWs drop all packets with EH (and
obviously this is only IPv6) so an Internet wide attack might not
be so effective (yet!).

By my calculation, the worse case packet with TLVs in a standard
1500 byte MTU packet that would be processed by the stack contains
1282 invidual TLVs (including pad TLVS) or 724 two byte TLVs. I
wrote a quick test program that floods a whole bunch of these
packets to a host and sure enough there is substantial time spent
in ip6_parse_tlv. These packets contain nothing but unknown TLVS
(that are ignored), TLV padding, and bogus UDP header with zero
payload length.

  25.38%  [kernel]                    [k] __fib6_clean_all
  21.63%  [kernel]                    [k] ip6_parse_tlv
   4.21%  [kernel]                    [k] __local_bh_enable_ip
   2.18%  [kernel]                    [k] ip6_pol_route.isra.39
   1.98%  [kernel]                    [k] fib6_walk_continue
   1.88%  [kernel]                    [k] _raw_write_lock_bh
   1.65%  [kernel]                    [k] dst_release

This patch adds configurable limits to Destination and Hop-by-Hop
options. There are three limits that may be set:
  - Limit the number of options in a Hop-by-Hop or Destination options
    extension header.
  - Limit the byte length of a Hop-by-Hop or Destination options
    extension header.
  - Disallow unrecognized options in a Hop-by-Hop or Destination
    options extension header.

The limits are set in corresponding sysctls:

  ipv6.sysctl.max_dst_opts_cnt
  ipv6.sysctl.max_hbh_opts_cnt
  ipv6.sysctl.max_dst_opts_len
  ipv6.sysctl.max_hbh_opts_len

If a max_*_opts_cnt is less than zero then unknown TLVs are disallowed.
The number of known TLVs that are allowed is the absolute value of
this number.

If a limit is exceeded when processing an extension header the packet is
dropped.

Default values are set to 8 for options counts, and set to INT_MAX
for maximum length. Note the choice to limit options to 8 is an
arbitrary guess (roughly based on the fact that the stack supports
three HBH options and just one destination option).

These limits have being proposed in draft-ietf-6man-rfc6434-bis.

Tested (by Martin Lau)

I tested out 1 thread (i.e. one raw_udp process).

I changed the net.ipv6.max_dst_(opts|hbh)_number between 8 to 2048.
With sysctls setting to 2048, the softirq% is packed to 100%.
With 8, the softirq% is almost unnoticable from mpstat.

v2;
  - Code and documention cleanup.
  - Change references of RFC2460 to be RFC8200.
  - Add reference to RFC6434-bis where the limits will be in standard.
Signed-off-by: NTom Herbert <tom@quantonium.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Reflecting IPv6 Flow Label at server nodes is useful in environments
that employ multipath routing to load balance the requests. As "IPv6
Flow Label Reflection" standard draft [1] points out - ICMPv6 PTB error
messages generated in response to a downstream packets from the server
can be routed by a load balancer back to the original server without
looking at transport headers, if the server applies the flow label
reflection. This enables the Path MTU Discovery past the ECMP router in
load-balance or anycast environments where each server node is reachable
by only one path.

Introduce a sysctl to enable flow label reflection per net namespace for
all newly created sockets. Same could be earlier achieved only per
socket by setting the IPV6_FL_F_REFLECT flag for the IPV6_FLOWLABEL_MGR
socket option.

[1] https://tools.ietf.org/html/draft-wang-6man-flow-label-reflection-01Signed-off-by: NJakub Sitnicki <jkbs@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This works in exactly the same way as the CIPSO label cache.
The idea is to allow the lsm to cache the result of a secattr
lookup so that it doesn't need to perform the lookup for
every skbuff.

It introduces two sysctl controls:
 calipso_cache_enable - enables/disables the cache.
 calipso_cache_bucket_size - sets the size of a cache bucket.
Signed-off-by: NHuw Davies <huw@codeweavers.com>
Signed-off-by: NPaul Moore <paul@paul-moore.com>

Change the meaning of net.ipv6.auto_flowlabels to provide a mode for
automatic flow labels generation. There are four modes:

0: flow labels are disabled
1: flow labels are enabled, sockets can opt-out
2: flow labels are allowed, sockets can opt-in
3: flow labels are enabled and enforced, no opt-out for sockets

np->autoflowlabel is initialized according to the sysctl value.
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support to allow non-local binds similar to how this was done for IPv4.
Non-local binds are very useful in emulating the Internet in a box, etc.

This add the ip_nonlocal_bind sysctl under ipv6.

Testing:

Set up nonlocal binding and receive routing on a host, e.g.:

ip -6 rule add from ::/0 iif eth0 lookup 200
ip -6 route add local 2001:0:0:1::/64 dev lo proto kernel scope host table 200
sysctl -w net.ipv6.ip_nonlocal_bind=1

Set up routing to 2001:0:0:1::/64 on peer to go to first host

ping6 -I 2001:0:0:1::1 peer-address -- to verify
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch divides the IPv6 flow label space into two ranges:
0-7ffff is reserved for flow label manager, 80000-fffff will be
used for creating auto flow labels (per RFC6438). This only affects how
labels are set on transmit, it does not affect receive. This range split
can be disbaled by systcl.

Background:

IPv6 flow labels have been an unmitigated disappointment thus far
in the lifetime of IPv6. Support in HW devices to use them for ECMP
is lacking, and OSes don't turn them on by default. If we had these
we could get much better hashing in IPv6 networks without resorting
to DPI, possibly eliminating some of the motivations to to define new
encaps in UDP just for getting ECMP.

Unfortunately, the initial specfications of IPv6 did not clarify
how they are to be used. There has always been a vague concept that
these can be used for ECMP, flow hashing, etc. and we do now have a
good standard how to this in RFC6438. The problem is that flow labels
can be either stateful or stateless (as in RFC6438), and we are
presented with the possibility that a stateless label may collide
with a stateful one.  Attempts to split the flow label space were
rejected in IETF. When we added support in Linux for RFC6438, we
could not turn on flow labels by default due to this conflict.

This patch splits the flow label space and should give us
a path to enabling auto flow labels by default for all IPv6 packets.
This is an API change so we need to consider compatibility with
existing deployment. The stateful range is chosen to be the lower
values in hopes that most uses would have chosen small numbers.

Once we resolve the stateless/stateful issue, we can proceed to
look at enabling RFC6438 flow labels by default (starting with
scaled testing).
Signed-off-by: NTom Herbert <tom@herbertland.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The ipv6 code uses a mixture of coding styles. In some instances check for NULL
pointer is done as x == NULL and sometimes as !x. !x is preferred according to
checkpatch and this patch makes the code consistent by adopting the latter
form.

No changes detected by objdiff.
Signed-off-by: NIan Morris <ipm@chirality.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is specified by RFC 7217.

Cc: Erik Kline <ek@google.com>
Cc: Fernando Gont <fgont@si6networks.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Cc: YOSHIFUJI Hideaki/吉藤英明 <hideaki.yoshifuji@miraclelinux.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds a new sysctl_mld_qrv knob to configure the mldv1/v2 query
robustness variable. It specifies how many retransmit of unsolicited mld
retransmit should happen. Admins might want to tune this on lossy links.

Also reset mld state on interface down/up, so we pick up new sysctl
settings during interface up event.

IPv6 certification requests this knob to be available.

I didn't make this knob netns specific, as it is mostly a setting in a
physical environment and should be per host.

Cc: Flavio Leitner <fbl@redhat.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: NFlavio Leitner <fbl@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fixes: e110861f ("net: add a sysctl to reflect the fwmark on replies")
Cc: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Automatically generate flow labels for IPv6 packets on transmit.
The flow label is computed based on skb_get_hash. The flow label will
only automatically be set when it is zero otherwise (i.e. flow label
manager hasn't set one). This supports the transmit side functionality
of RFC 6438.

Added an IPv6 sysctl auto_flowlabels to enable/disable this behavior
system wide, and added IPV6_AUTOFLOWLABEL socket option to enable this
functionality per socket.

By default, auto flowlabels are disabled to avoid possible conflicts
with flow label manager, however if this feature proves useful we
may want to enable it by default.

It should also be noted that FreeBSD has already implemented automatic
flow labels (including the sysctl and socket option). In FreeBSD,
automatic flow labels default to enabled.

Performance impact:

Running super_netperf with 200 flows for TCP_RR and UDP_RR for
IPv6. Note that in UDP case, __skb_get_hash will be called for
every packet with explains slight regression. In the TCP case
the hash is saved in the socket so there is no regression.

Automatic flow labels disabled:

  TCP_RR:
    86.53% CPU utilization
    127/195/322 90/95/99% latencies
    1.40498e+06 tps

  UDP_RR:
    90.70% CPU utilization
    118/168/243 90/95/99% latencies
    1.50309e+06 tps

Automatic flow labels enabled:

  TCP_RR:
    85.90% CPU utilization
    128/199/337 90/95/99% latencies
    1.40051e+06

  UDP_RR
    92.61% CPU utilization
    115/164/236 90/95/99% latencies
    1.4687e+06
Signed-off-by: NTom Herbert <therbert@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Kernel-originated IP packets that have no user socket associated
with them (e.g., ICMP errors and echo replies, TCP RSTs, etc.)
are emitted with a mark of zero. Add a sysctl to make them have
the same mark as the packet they are replying to.

This allows an administrator that wishes to do so to use
mark-based routing, firewalling, etc. for these replies by
marking the original packets inbound.

Tested using user-mode linux:
 - ICMP/ICMPv6 echo replies and errors.
 - TCP RST packets (IPv4 and IPv6).
Signed-off-by: NLorenzo Colitti <lorenzo@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

With the introduction of IPV6_FL_F_REFLECT, there is no guarantee of
flow label unicity. This patch introduces a new sysctl to protect the old
behaviour, enable by default.

Changelog of V3:
 * rename ip6_flowlabel_consistency to flowlabel_consistency
 * use net_info_ratelimited()
 * checkpatch cleanups
Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change move anycast_src_echo_reply sysctl with other ipv6 sysctls.
Suggested-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NFrancois-Xavier Le Bail <fx.lebail@yahoo.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change allows to follow a recommandation of RFC4942.

- Add "anycast_src_echo_reply" sysctl to control the use of anycast addresses
  as source addresses for ICMPv6 echo reply. This sysctl is false by default
  to preserve existing behavior.
- Add inline check ipv6_anycast_destination().
- Use them in icmpv6_echo_reply().

Reference:
RFC4942 - IPv6 Transition/Coexistence Security Considerations
   (http://tools.ietf.org/html/rfc4942#section-2.1.6)

2.1.6. Anycast Traffic Identification and Security

   [...]
   To avoid exposing knowledge about the internal structure of the
   network, it is recommended that anycast servers now take advantage of
   the ability to return responses with the anycast address as the
   source address if possible.
Signed-off-by: NFrancois-Xavier Le Bail <fx.lebail@yahoo.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Reduce the uses of this unnecessary typedef.

Done via perl script:

$ git grep --name-only -w ctl_table net | \
  xargs perl -p -i -e '\
	sub trim { my ($local) = @_; $local =~ s/(^\s+|\s+$)//g; return $local; } \
        s/\b(?<!struct\s)ctl_table\b(\s*\*\s*|\s+\w+)/"struct ctl_table " . trim($1)/ge'

Reflow the modified lines that now exceed 80 columns.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

- Enable the per device ipv4 sysctls:
   net/ipv4/conf/<if>/forwarding
   net/ipv4/conf/<if>/mc_forwarding
   net/ipv4/conf/<if>/accept_redirects
   net/ipv4/conf/<if>/secure_redirects
   net/ipv4/conf/<if>/shared_media
   net/ipv4/conf/<if>/rp_filter
   net/ipv4/conf/<if>/send_redirects
   net/ipv4/conf/<if>/accept_source_route
   net/ipv4/conf/<if>/accept_local
   net/ipv4/conf/<if>/src_valid_mark
   net/ipv4/conf/<if>/proxy_arp
   net/ipv4/conf/<if>/medium_id
   net/ipv4/conf/<if>/bootp_relay
   net/ipv4/conf/<if>/log_martians
   net/ipv4/conf/<if>/tag
   net/ipv4/conf/<if>/arp_filter
   net/ipv4/conf/<if>/arp_announce
   net/ipv4/conf/<if>/arp_ignore
   net/ipv4/conf/<if>/arp_accept
   net/ipv4/conf/<if>/arp_notify
   net/ipv4/conf/<if>/proxy_arp_pvlan
   net/ipv4/conf/<if>/disable_xfrm
   net/ipv4/conf/<if>/disable_policy
   net/ipv4/conf/<if>/force_igmp_version
   net/ipv4/conf/<if>/promote_secondaries
   net/ipv4/conf/<if>/route_localnet

- Enable the global ipv4 sysctl:
   net/ipv4/ip_forward

- Enable the per device ipv6 sysctls:
   net/ipv6/conf/<if>/forwarding
   net/ipv6/conf/<if>/hop_limit
   net/ipv6/conf/<if>/mtu
   net/ipv6/conf/<if>/accept_ra
   net/ipv6/conf/<if>/accept_redirects
   net/ipv6/conf/<if>/autoconf
   net/ipv6/conf/<if>/dad_transmits
   net/ipv6/conf/<if>/router_solicitations
   net/ipv6/conf/<if>/router_solicitation_interval
   net/ipv6/conf/<if>/router_solicitation_delay
   net/ipv6/conf/<if>/force_mld_version
   net/ipv6/conf/<if>/use_tempaddr
   net/ipv6/conf/<if>/temp_valid_lft
   net/ipv6/conf/<if>/temp_prefered_lft
   net/ipv6/conf/<if>/regen_max_retry
   net/ipv6/conf/<if>/max_desync_factor
   net/ipv6/conf/<if>/max_addresses
   net/ipv6/conf/<if>/accept_ra_defrtr
   net/ipv6/conf/<if>/accept_ra_pinfo
   net/ipv6/conf/<if>/accept_ra_rtr_pref
   net/ipv6/conf/<if>/router_probe_interval
   net/ipv6/conf/<if>/accept_ra_rt_info_max_plen
   net/ipv6/conf/<if>/proxy_ndp
   net/ipv6/conf/<if>/accept_source_route
   net/ipv6/conf/<if>/optimistic_dad
   net/ipv6/conf/<if>/mc_forwarding
   net/ipv6/conf/<if>/disable_ipv6
   net/ipv6/conf/<if>/accept_dad
   net/ipv6/conf/<if>/force_tllao

- Enable the global ipv6 sysctls:
   net/ipv6/bindv6only
   net/ipv6/icmp/ratelimit
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In preparation for supporting the creation of network namespaces
by unprivileged users, modify all of the per net sysctl exports
and refuse to allow them to unprivileged users.

This makes it safe for unprivileged users in general to access
per net sysctls, and allows sysctls to be exported to unprivileged
users on an individual basis as they are deemed safe.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We don't use struct ctl_path anymore so delete the exported constants.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The sysctl core no longer natively understands sysctl tables
with .child entries.

Split the ipv6_table to remove the .child entries.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

sysctl no longer requires explicit creation of directories.  The neigh
directory is always populated with at least a default entry so this
should cause no user visible changes.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This makes it clearer which sysctls are relative to your current network
namespace.

This makes it a little less error prone by not exposing sysctls for the
initial network namespace in other namespaces.

This is the same way we handle all of our other network interfaces to
userspace and I can't honestly remember why we didn't do this for
sysctls right from the start.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

register_sysctl_rotable never caught on as an interesting way to
register sysctls.  My take on the situation is that what we want are
sysctls that we can only see in the initial network namespace.  What we
have implemented with register_sysctl_rotable are sysctls that we can
see in all of the network namespaces and can only change in the initial
network namespace.

That is a very silly way to go.  Just register the network sysctls
in the initial network namespace and we don't have any weird special
cases to deal with.

The sysctls affected are:
/proc/sys/net/ipv4/ipfrag_secret_interval
/proc/sys/net/ipv4/ipfrag_max_dist
/proc/sys/net/ipv6/ip6frag_secret_interval
/proc/sys/net/ipv6/mld_max_msf

I really don't expect anyone will miss them if they can't read them in a
child user namespace.

CC: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NPavel Emelyanov <xemul@parallels.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

When I was fixing issues with unregisgtering tables under /proc/sys/net/ipv6/neigh
by adding a mount point it appears I missed a critical ordering issue, in the
ipv6 initialization.  I had not realized that ipv6_sysctl_register is called
at the very end of the ipv6 initialization and in particular after we call
neigh_sysctl_register from ndisc_init.

"neigh" needs to be initialized in ipv6_static_sysctl_register which is
the first ipv6 table to initialized, and definitely before ndisc_init.
This removes the weirdness of duplicate tables while still providing a
"neigh" mount point which prevents races in sysctl unregistering.

This was initially reported at https://bugzilla.kernel.org/show_bug.cgi?id=31232
Reported-by: sunkan@zappa.cx
Signed-off-by: NEric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In my testing of 2.6.37 I was occassionally getting a warning about
sysctl table entries being unregistered in the wrong order.  Digging
in it turns out this dates back to the last great sysctl reorg done
where Al Viro introduced the requirement that sysctl directories
needed to be created before and destroyed after the files in them.

It turns out that in that great reorg /proc/sys/net/ipv6/neigh was
overlooked.  So this patch fixes that oversight and makes an annoying
warning message go away.

>------------[ cut here ]------------
>WARNING: at kernel/sysctl.c:1992 unregister_sysctl_table+0x134/0x164()
>Pid: 23951, comm: kworker/u:3 Not tainted 2.6.37-350888.2010AroraKernelBeta.fc14.x86_64 #1
>Call Trace:
> [<ffffffff8103e034>] warn_slowpath_common+0x80/0x98
> [<ffffffff8103e061>] warn_slowpath_null+0x15/0x17
> [<ffffffff810452f8>] unregister_sysctl_table+0x134/0x164
> [<ffffffff810e7834>] ? kfree+0xc4/0xd1
> [<ffffffff813439b2>] neigh_sysctl_unregister+0x22/0x3a
> [<ffffffffa02cd14e>] addrconf_ifdown+0x33f/0x37b [ipv6]
> [<ffffffff81331ec2>] ? skb_dequeue+0x5f/0x6b
> [<ffffffffa02ce4a5>] addrconf_notify+0x69b/0x75c [ipv6]
> [<ffffffffa02eb953>] ? ip6mr_device_event+0x98/0xa9 [ipv6]
> [<ffffffff813d2413>] notifier_call_chain+0x32/0x5e
> [<ffffffff8105bdea>] raw_notifier_call_chain+0xf/0x11
> [<ffffffff8133cdac>] call_netdevice_notifiers+0x45/0x4a
> [<ffffffff8133d2b0>] rollback_registered_many+0x118/0x201
> [<ffffffff8133d3af>] unregister_netdevice_many+0x16/0x6d
> [<ffffffff8133d571>] default_device_exit_batch+0xa4/0xb8
> [<ffffffff81337c42>] ? cleanup_net+0x0/0x194
> [<ffffffff81337a2a>] ops_exit_list+0x4e/0x56
> [<ffffffff81337d36>] cleanup_net+0xf4/0x194
> [<ffffffff81053318>] process_one_work+0x187/0x280
> [<ffffffff8105441b>] worker_thread+0xff/0x19f
> [<ffffffff8105431c>] ? worker_thread+0x0/0x19f
> [<ffffffff8105776d>] kthread+0x7d/0x85
> [<ffffffff81003824>] kernel_thread_helper+0x4/0x10
> [<ffffffff810576f0>] ? kthread+0x0/0x85
> [<ffffffff81003820>] ? kernel_thread_helper+0x0/0x10
>---[ end trace 8a7e9310b35e9486 ]---
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.
Signed-off-by: NTejun Heo <tj@kernel.org>
Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

__net_init/__net_exit are apparently not going away, so use them
to full extent.

In some cases __net_init was removed, because it was called from
__net_exit code.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that sys_sysctl is a compatiblity wrapper around /proc/sys
all sysctl strategy routines, and all ctl_name and strategy
entries in the sysctl tables are unused, and can be
revmoed.

In addition neigh_sysctl_register has been modified to no longer
take a strategy argument and it's callers have been modified not
to pass one.

Cc: "David Miller" <davem@davemloft.net>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: netdev@vger.kernel.org
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>

This renames away a variable clash:
 * ipv6_table[] is declared as a static global table;
 * ipv6_sysctl_net_init() uses ipv6_table to refer/destroy dynamic memory;
 * ipv6_sysctl_net_exit() also uses ipv6_table for the same purpose;
 * both the two last functions call kfree() on ipv6_table.
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Acked-by: NTheodore Ts'o <tytso@mit.edu>
Acked-by: NMark Fasheh <mfasheh@suse.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Cc: James Morris <jmorris@namei.org>
Acked-by: NCasey Schaufler <casey@schaufler-ca.com>
Acked-by: NTakashi Iwai <tiwai@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I want to compile out proc_* and sysctl_* handlers totally and
stub them to NULL depending on config options, however usage of &
will prevent this, since taking adress of NULL pointer will break
compilation.

So, drop & in front of every ->proc_handler and every ->strategy
handler, it was never needed in fact.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Braino: net.ipv6 in ipv6 skeleton has no business in rotable
class
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Piss-poor sysctl registration API strikes again, film at 11...

What we really need is _pathname_ required to be present in already
registered table, so that kernel could warn about bad order.  That's the
next target for sysctl stuff (and generally saner and more explicit
order of initialization of ipv[46] internals wouldn't hurt either).

For the time being, here are full fixups required by ..._rotable()
stuff; we make per-net sysctl sets descendents of "ro" one and make sure
that sufficient skeleton is there before we start registering per-net
sysctls.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Piss-poor sysctl registration API strikes again, film at 11...
What we really need is _pathname_ required to be present in
already registered table, so that kernel could warn about bad
order.  That's the next target for sysctl stuff (and generally
saner and more explicit order of initialization of ipv[46]
internals wouldn't hurt either).

For the time being, here are full fixups required by ..._rotable()
stuff; we make per-net sysctl sets descendents of "ro" one and
make sure that sufficient skeleton is there before we start registering
per-net sysctls.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There are some sysctls left to be switched to read-only,
but they are all in ipv6, so complete with them.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Move initialization bits for subsystem sysctl tables to
appropriate functions.
 - route
 - icmp
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>

In error path, we do need to free memory just allocated.
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is a preparation for sysctl netns-ization.
Move the ctl tables to the files, where the tuning
variables reside. Plus make the helpers to register
the tables.

This will simplify the later patches and will keep
similar things closer to each other.

ipv4, ipv6 and conntrack_reasm are patched differently,
but the result is all the tables are in appropriate files.
Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix the following sparse warnings:
| net/ipv6/route.c:2491:18: warning: symbol 'ipv6_route_sysctl_init' was not declared. Should it be static?
| net/ipv6/icmp.c:922:18: warning: symbol 'ipv6_icmp_sysctl_init' was not declared. Should it be static?
| net/ipv6/reassembly.c:628:6: warning: symbol 'ipv6_frag_sysctl_init' was not declared. Should it be static?
Signed-off-by: NYOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>