The variable hlen is initialized but never used otherwise.
The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)
// <smpl>
@@
type T;
identifier i;
constant C;
@@
(
extern T i;
|
- T i;
<+... when != i
- i = C;
...+>
)
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based on notice from "Colin" <colins@sjtu.edu.cn>.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now the ESP uses the AEAD interface even for algorithms which are
not combined mode, we need to select CONFIG_CRYPTO_AUTHENC as
otherwise only combined mode algorithms will work.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use proc_create() to make sure that ->proc_fops be setup before gluing
PDE to main tree.
Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Because we use shared tfm objects in order to conserve memory,
(each tfm requires 128K of vmalloc memory), BH needs to be turned
off on output as that can occur in process context.
Previously this was done implicitly by the xfrm output code.
That was lost when it became lockless. So we need to add the
BH disabling to IPComp directly.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
In error path, we do need to free memory just allocated.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Four tunnel drivers (ip_gre, ipip, ip6_tunnel and sit) can receive a
pre-defined name for a device from the userspace. Since these drivers
call the register_netdevice() (rtnl_lock, is held), which does _not_
generate the device's name, this name may contain a '%' character.
Not sure how bad is this to have a device with a '%' in its name, but
all the other places either use the register_netdev(), which call the
dev_alloc_name(), or explicitly call the dev_alloc_name() before
registering, i.e. do not allow for such names.
This had to be prior to the commit 34cc7b, but I forgot to number the
patches and this one got lost, sorry.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add some more missing initializations of the new nl_info.nl_net field
in IPv6 stack. This field will be used when network namespaces are
fully supported.
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use the added dev_alloc_name() call to create tunnel device name,
rather than iterate in a hand-made loop with an artificial limit.
Thanks Patrick for noticing this.
[ The way this works is, when the device is actually registered,
the generic code noticed the '%' in the name and invokes
dev_alloc_name() to fully resolve the name. -DaveM ]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
As reported by Tomas Simonaitis <tomas.simonaitis@gmail.com>,
inserting new data in skbs queued over {ip,ip6,nfnetlink}_queue
triggers a SKB_LINEAR_ASSERT in skb_put().
Going back through the git history, it seems this bug is present since
at least 2.6.12-rc2, probably even since the removal of
skb_linearize() for netfilter.
Linearize non-linear skbs through skb_copy_expand() when enlarging
them. Tested by Thomas, fixes bugzilla #9933.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The result of the ip_route_output is not assigned to skb. This means that
- it is leaked
- possible OOPS below dereferrencing skb->dst
- no ICMP message for this case
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rusty hardcoded the old module code.
We can remove it now.
Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I managed to reverse the local_df test when forward-porting this
patch so it actually makes things worse by never fragmenting at
all.
Thanks to David Stevens for testing and reporting this bug.
Bill Fink pointed out that the local_df setting is also the wrong
way around.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Al Viro spotted a bogus use of u64 on the input sequence number which
is big-endian. This patch fixes it by giving the input sequence number
its own member in the xfrm_skb_cb structure.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is a long-standing bug in the IPsec IPv6 code that breaks
when we emit a IPsec tunnel-mode datagram packet. The problem
is that the code the emits the packet assumes the IPv6 stack
will fragment it later, but the IPv6 stack assumes that whoever
is emitting the packet is going to pre-fragment the packet.
In the long term we need to fix both sides, e.g., to get the
datagram code to pre-fragment as well as to get the IPv6 stack
to fragment locally generated tunnel-mode packet.
For now this patch does the second part which should make it
work for the IPsec host case.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch replaces the explicit usage of the magic constant "1024"
with IP6_RT_PRIO_USER in the IPV6 tree.
Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Somewhere along the development of my ICMP relookup patch the header
length check went AWOL on the non-IPsec path. This patch restores the
check.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The port offset calculations depend on the protocol family, but, as
Adrian noticed, I broke this logic with the commit
5ee31fc1ec
[INET]: Consolidate inet(6)_hash_connect.
Return this logic back, by passing the port offset directly into the
consolidated function.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Noticed-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This way we can remove TCP and DCCP specific versions of
sk->sk_prot->get_port: both v4 and v6 use inet_csk_get_port
sk->sk_prot->hash: inet_hash is directly used, only v6 need
a specific version to deal with mapped sockets
sk->sk_prot->unhash: both v4 and v6 use inet_hash directly
struct inet_connection_sock_af_ops also gets a new member, bind_conflict, so
that inet_csk_get_port can find the per family routine.
Now only the lookup routines receive as a parameter a struct inet_hashtable.
With this we further reuse code, reducing the difference among INET transport
protocols.
Eventually work has to be done on UDP and SCTP to make them share this
infrastructure and get as a bonus inet_diag interfaces so that iproute can be
used with these protocols.
net-2.6/net/ipv4/inet_hashtables.c:
struct proto | +8
struct inet_connection_sock_af_ops | +8
2 structs changed
__inet_hash_nolisten | +18
__inet_hash | -210
inet_put_port | +8
inet_bind_bucket_create | +1
__inet_hash_connect | -8
5 functions changed, 27 bytes added, 218 bytes removed, diff: -191
net-2.6/net/core/sock.c:
proto_seq_show | +3
1 function changed, 3 bytes added, diff: +3
net-2.6/net/ipv4/inet_connection_sock.c:
inet_csk_get_port | +15
1 function changed, 15 bytes added, diff: +15
net-2.6/net/ipv4/tcp.c:
tcp_set_state | -7
1 function changed, 7 bytes removed, diff: -7
net-2.6/net/ipv4/tcp_ipv4.c:
tcp_v4_get_port | -31
tcp_v4_hash | -48
tcp_v4_destroy_sock | -7
tcp_v4_syn_recv_sock | -2
tcp_unhash | -179
5 functions changed, 267 bytes removed, diff: -267
net-2.6/net/ipv6/inet6_hashtables.c:
__inet6_hash | +8
1 function changed, 8 bytes added, diff: +8
net-2.6/net/ipv4/inet_hashtables.c:
inet_unhash | +190
inet_hash | +242
2 functions changed, 432 bytes added, diff: +432
vmlinux:
16 functions changed, 485 bytes added, 492 bytes removed, diff: -7
/home/acme/git/net-2.6/net/ipv6/tcp_ipv6.c:
tcp_v6_get_port | -31
tcp_v6_hash | -7
tcp_v6_syn_recv_sock | -9
3 functions changed, 47 bytes removed, diff: -47
/home/acme/git/net-2.6/net/dccp/proto.c:
dccp_destroy_sock | -7
dccp_unhash | -179
dccp_hash | -49
dccp_set_state | -7
dccp_done | +1
5 functions changed, 1 bytes added, 242 bytes removed, diff: -241
/home/acme/git/net-2.6/net/dccp/ipv4.c:
dccp_v4_get_port | -31
dccp_v4_request_recv_sock | -2
2 functions changed, 33 bytes removed, diff: -33
/home/acme/git/net-2.6/net/dccp/ipv6.c:
dccp_v6_get_port | -31
dccp_v6_hash | -7
dccp_v6_request_recv_sock | +5
3 functions changed, 5 bytes added, 38 bytes removed, diff: -33
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This is needed because in ndisc.c, we have:
static void ndisc_router_discovery(struct sk_buff *skb)
{
// ...
if (ndopts.nd_opts_mtu) {
// ...
if (rt)
rt->u.dst.metrics[RTAX_MTU-1] = mtu;
rt6_mtu_change(skb->dev, mtu);
// ...
}
Since the mtu is set directly here, rt6_mtu_change_route thinks that
it is unchanged, and so it fails to update the MSS accordingly. This
patch lets rt6_mtu_change_route still update MSS if old_mtu == new_mtu.
Signed-off-by: Jim Paris <jim@jtan.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add the net parameter to udp_get_port family of calls and
udp_lookup one and use it to filter sockets.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a net argument to inet6_lookup and propagate it further.
Actually, this is tcp-v6 implementation of what was done for
tcp-v4 sockets in a previous patch.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
These two functions are the same except for what they call
to "check_established" and "hash" for a socket.
This saves half-a-kilo for ipv4 and ipv6.
add/remove: 1/0 grow/shrink: 1/4 up/down: 582/-1128 (-546)
function old new delta
__inet_hash_connect - 577 +577
arp_ignore 108 113 +5
static.hint 8 4 -4
rt_worker_func 376 372 -4
inet6_hash_connect 584 25 -559
inet_hash_connect 586 25 -561
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We have INET_MATCH, INET_TW_MATCH and INET6_MATCH to test sockets and
twbuckets for matching, but ipv6 twbuckets are tested manually.
Here's the INET6_TW_MATCH to help with it.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reported by Ingo Molnar:
net/built-in.o: In function `ip_queue_init':
ip_queue.c:(.init.text+0x322c): undefined reference to `net_ipv4_ctl_path'
Fix the build error and also handle CONFIG_PROC_FS=n properly.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Constify a few data tables use const qualifiers on variables where
possible in the nf_conntrack_icmp* sources.
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rename all "conntrack" variables to "ct" for more consistency and
avoiding some overly long lines.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
CHECK net/ipv6/netfilter/nf_conntrack_reasm.c
net/ipv6/netfilter/nf_conntrack_reasm.c:77:18: warning: symbol 'nf_ct_ipv6_sysctl_table' was not declared. Should it be static?
net/ipv6/netfilter/nf_conntrack_reasm.c:586:16: warning: symbol 'nf_ct_frag6_gather' was not declared. Should it be static?
net/ipv6/netfilter/nf_conntrack_reasm.c:662:6: warning: symbol 'nf_ct_frag6_output' was not declared. Should it be static?
net/ipv6/netfilter/nf_conntrack_reasm.c:683:5: warning: symbol 'nf_ct_frag6_kfree_frags' was not declared. Should it be static?
net/ipv6/netfilter/nf_conntrack_reasm.c:698:5: warning: symbol 'nf_ct_frag6_init' was not declared. Should it be static?
net/ipv6/netfilter/nf_conntrack_reasm.c:717:6: warning: symbol 'nf_ct_frag6_cleanup' was not declared. Should it be static?
Based on patch by Stephen Hemminger with suggestions by Yasuyuki KOZAKAI.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
CHECK net/ipv4/netfilter/ip_tables.c
net/ipv4/netfilter/ip_tables.c:1453:8: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/ip_tables.c:1453:8: expected int *size
net/ipv4/netfilter/ip_tables.c:1453:8: got unsigned int [usertype] *size
net/ipv4/netfilter/ip_tables.c:1458:44: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/ip_tables.c:1458:44: expected int *size
net/ipv4/netfilter/ip_tables.c:1458:44: got unsigned int [usertype] *size
net/ipv4/netfilter/ip_tables.c:1603:2: warning: incorrect type in argument 2 (different signedness)
net/ipv4/netfilter/ip_tables.c:1603:2: expected unsigned int *i
net/ipv4/netfilter/ip_tables.c:1603:2: got int *<noident>
net/ipv4/netfilter/ip_tables.c:1627:8: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/ip_tables.c:1627:8: expected int *size
net/ipv4/netfilter/ip_tables.c:1627:8: got unsigned int *size
net/ipv4/netfilter/ip_tables.c:1634:40: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/ip_tables.c:1634:40: expected int *size
net/ipv4/netfilter/ip_tables.c:1634:40: got unsigned int *size
net/ipv4/netfilter/ip_tables.c:1653:8: warning: incorrect type in argument 5 (different signedness)
net/ipv4/netfilter/ip_tables.c:1653:8: expected unsigned int *i
net/ipv4/netfilter/ip_tables.c:1653:8: got int *<noident>
net/ipv4/netfilter/ip_tables.c:1666:2: warning: incorrect type in argument 2 (different signedness)
net/ipv4/netfilter/ip_tables.c:1666:2: expected unsigned int *i
net/ipv4/netfilter/ip_tables.c:1666:2: got int *<noident>
CHECK net/ipv4/netfilter/arp_tables.c
net/ipv4/netfilter/arp_tables.c:1285:40: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/arp_tables.c:1285:40: expected int *size
net/ipv4/netfilter/arp_tables.c:1285:40: got unsigned int *size
net/ipv4/netfilter/arp_tables.c:1543:44: warning: incorrect type in argument 3 (different signedness)
net/ipv4/netfilter/arp_tables.c:1543:44: expected int *size
net/ipv4/netfilter/arp_tables.c:1543:44: got unsigned int [usertype] *size
CHECK net/ipv6/netfilter/ip6_tables.c
net/ipv6/netfilter/ip6_tables.c:1481:8: warning: incorrect type in argument 3 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1481:8: expected int *size
net/ipv6/netfilter/ip6_tables.c:1481:8: got unsigned int [usertype] *size
net/ipv6/netfilter/ip6_tables.c:1486:44: warning: incorrect type in argument 3 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1486:44: expected int *size
net/ipv6/netfilter/ip6_tables.c:1486:44: got unsigned int [usertype] *size
net/ipv6/netfilter/ip6_tables.c:1631:2: warning: incorrect type in argument 2 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1631:2: expected unsigned int *i
net/ipv6/netfilter/ip6_tables.c:1631:2: got int *<noident>
net/ipv6/netfilter/ip6_tables.c:1655:8: warning: incorrect type in argument 3 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1655:8: expected int *size
net/ipv6/netfilter/ip6_tables.c:1655:8: got unsigned int *size
net/ipv6/netfilter/ip6_tables.c:1662:40: warning: incorrect type in argument 3 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1662:40: expected int *size
net/ipv6/netfilter/ip6_tables.c:1662:40: got unsigned int *size
net/ipv6/netfilter/ip6_tables.c:1680:8: warning: incorrect type in argument 5 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1680:8: expected unsigned int *i
net/ipv6/netfilter/ip6_tables.c:1680:8: got int *<noident>
net/ipv6/netfilter/ip6_tables.c:1693:2: warning: incorrect type in argument 2 (different signedness)
net/ipv6/netfilter/ip6_tables.c:1693:2: expected unsigned int *i
net/ipv6/netfilter/ip6_tables.c:1693:2: got int *<noident>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When number of entries exceeds number of initial entries, foo-tables code
will pin table module. But during table unregister on netns stop,
that additional pin was forgotten.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Now it's possible to list and manipulate per-netns ip6tables rules.
Filtering decisions are based on init_net's table so far.
P.S.: remove init_net check in inet6_create() to see the effect
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
* Propagate netns from userspace down to xt_find_table_lock()
* Register ip6 tables in netns (modules still use init_net)
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Typical table module registers xt_table structure (i.e. packet_filter)
and link it to list during it. We can't use one template for it because
corresponding list_head will become corrupted. We also can't unregister
with template because it wasn't changed at all and thus doesn't know in
which list it is.
So, we duplicate template at the very first step of table registration.
Table modules will save it for use during unregistration time and actual
filtering.
Do it at once to not screw bisection.
P.S.: renaming i.e. packet_filter => __packet_filter is temporary until
full netnsization of table modules is done.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
In fact all we want is per-netns set of rules, however doing that will
unnecessary complicate routines such as ipt_hook()/ipt_do_table, so
make full xt_table array per-netns.
Every user stubbed with init_net for a while.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Switch from 0/-E to ptr/PTR_ERR convention.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
The address of IPv6 raw sockets was shown in the wrong format, from
IPv4 ones. The problem has been introduced by the commit
42a73808ed ("[RAW]: Consolidate proc
interface.")
Thanks to Adrian Bunk who originally noticed the problem.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Different hashtables are used for IPv6 and IPv4 raw sockets, so no
need to check the socket family in the iterator over hashtables. Clean
this out.
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
All but one struct dst_ops static initializations miss explicit
initialization of entries field.
As this field is atomic_t, we should use ATOMIC_INIT(0), and not
rely on atomic_t implementation.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add missing initialization of the new nl_info.nl_net field in
rtm_to_fib6_config(). This will be needed the store network namespace
associated to the fib6_config struct.
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
A userspace program may wish to set the mark for each packets its send
without using the netfilter MARK target. Changing the mark can be used
for mark based routing without netfilter or for packet filtering.
It requires CAP_NET_ADMIN capability.
Signed-off-by: Laszlo Attila Toth <panther@balabit.hu>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When I moved the nexthdr setting out of IPComp I accidently moved
the reading of ipch->nexthdr after the decompression. Unfortunately
this means that we'd be reading from a stale ipch pointer which
doesn't work very well.
This patch moves the reading up so that we get the correct nexthdr
value.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
When ip_fragment has to hit the slow path the value of skb->truesize
may go out of sync because we would have updated it without changing
the packet length. This violates the constraints on truesize.
This patch postpones the update of skb->truesize to prevent this.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds support for combined mode algorithms with GCM being
the first algorithm supported.
Combined mode algorithms can be added through the xfrm_user interface
using the new algorithm payload type XFRMA_ALG_AEAD. Each algorithms
is identified by its name and the ICV length.
For the purposes of matching algorithms in xfrm_tmpl structures,
combined mode algorithms occupy the same name space as encryption
algorithms. This is in line with how they are negotiated using IKE.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch converts ESP to use the crypto_aead interface and in particular
the authenc algorithm. This lays the foundations for future support of
combined mode algorithms.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
We want IPV6HEADER matching for the non-advanced default netfilter
configuration, since it's part of the standard netfilter setup of at
least some distributions (eg Fedora).
Otherwise NETFILTER_ADVANCED loses much of its point, since even
non-advanced users would have to enable all the advanced options just to
get a working IPv6 netfilter setup.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>