The NAT helpr hooks are protected by RCU, but all of the
conntrack helpers test and use the global pointers instead
of copying them first using rcu_dereference()

Also replace synchronize_net() by synchronize_rcu() for clarity
since sychronizing only with packet receive processing is
insufficient to prevent races.
Signed-off-by: NPatrick McHardy <kaber@trash.net>

We usually uses 'xxx_find_get' for function which increments
reference count.
Signed-off-by: NYasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

This patch adds /proc/net/ip_conntrack, /proc/net/ip_conntrack_expect and
/proc/net/stat/ip_conntrack files to keep old programs using them working.

The /proc/net/ip_conntrack and /proc/net/ip_conntrack_expect files show only
IPv4 entries, the /proc/net/stat/ip_conntrack shows global statistics.
Signed-off-by: NPatrick McHardy <kaber@trash.net>

This patch adds an option to keep the connection tracking sysctls visible
under their old names.
Signed-off-by: NPatrick McHardy <kaber@trash.net>

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

Add helper functions for sysctl registration with optional instantiating
of common path elements (like net/netfilter) and use it for support for
automatic registation of conntrack protocol sysctls.
Signed-off-by: NPatrick McHardy <kaber@trash.net>

Using extern in a C file is a bad idea because the compiler can't
catch type errors.
Signed-off-by: NPatrick McHardy <kaber@trash.net>

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

Only update the conntrack timer if there's been at least HZ jiffies since
the last update. Reduces the number of del_timer/add_timer cycles from one
per packet to one per connection per second (plus once for each state change
of a connection)

Should handle timer wraparounds and connection timeout changes.
Signed-off-by: NMartin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

Remove unused struct list_head from struct nf_conntrack_l3proto and
nf_conntrack_l4proto as all protocols are kept in arrays, not linked
lists.
Signed-off-by: NMartin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

Minor whitespace cleanup.
Signed-off-by: NMartin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

Remove the usage of ASSERT_READ_LOCK/ASSERT_WRITE_LOCK in nf_conntrack,
it didn't do anything, it was just an empty define and it uglified the code.
Signed-off-by: NMartin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

Add some more sanity checks when registering/unregistering l3/l4 protocols.
Signed-off-by: NMartin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

Rename 'struct nf_conntrack_protocol' to 'struct nf_conntrack_l4proto' in
order to help distinguish it from 'struct nf_conntrack_l3proto'. It gets
rather confusing with 'nf_conntrack_protocol'.
Signed-off-by: NMartin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

Place rarely written variables in the read-mostly section by using
__read_mostly
Signed-off-by: NMartin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

This patch splits out L3/L4 protocol handling into its own file
nf_conntrack_proto.c
Signed-off-by: NMartin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

This patch splits out the event cache into its own file
nf_conntrack_ecache.c
Signed-off-by: NMartin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

This patch splits out handling of helpers into its own file
nf_conntrack_helper.c
Signed-off-by: NMartin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

This patch splits out expectation handling into its own file
nf_conntrack_expect.c
Signed-off-by: NMartin Josefsson <gandalf@wlug.westbo.se>
Signed-off-by: NPatrick McHardy <kaber@trash.net>

This helps Vegas cope better with delayed ACKs, see
analysis at:

http://www.cs.caltech.edu/%7Eweixl/technical/ns2linux/known_linux/index.html#vegasSigned-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements a suggestion by Ian McDonald and

 1) Avoids tests against negative packet lengths by using unsigned int
    for packet payload lengths in the CCID send_packet()/packet_sent() routines

 2) As a consequence, it removes an now unnecessary test with regard to `len > 0'
    in ccid3_hc_tx_packet_sent: that condition is always true, since
      * negative packet lengths are avoided
      * ccid3_hc_tx_send_packet flags an error whenever the payload length is 0.
        As a consequence, ccid3_hc_tx_packet_sent is never called as all errors
        returned by ccid_hc_tx_send_packet are caught in dccp_write_xmit

 3) Removes the third argument of ccid_hc_tx_send_packet (the `len' parameter),
    since it is currently always set to skb->len. The code is updated with regard
    to this parameter change.
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: NIan McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

This implements the larger-initial-windows feature for CCID 3, as described in
section 5 of RFC 4342. When the first feedback packet arrives, the sender can
send up to 2..4 packets per RTT, instead of just one.

The patch further
 * reduces the number of timestamping calls by passing the timestamp value
   (which is computed in one of the calling functions anyway) as argument

 * renames one constant with a very long name into one which is shorter and
   resembles the one in RFC 3448 (t_mbi)

 * simplifies some of the min_t/max_t cases where both `x', `y' have the same
   type

Commiter note: renamed TFRC_t_mbi to TFRC_T_MBI, to follow Linux coding style.
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: NIan McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

To reflect the fact that this now is of no effect, not making apps
stop working, just be warned in the system log.
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

This removes and cleans up unused variables and structures which have become
unnecessary following the introduction of the EWMA patch to automatically track
the CCID 3 receiver/sender packet sizes `s'.

It deprecates the PACKET_SIZE socket option by returning an error code and
printing a deprecation warning if an application tries to read or write this
socket option.
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

Problem:

This corrects the setting of the nofeedback timer with regard to RFC
3448 - previously it was not set to max(4*R, 2*s/X) as specified. Using
the maximum of 1 second as upper bound (as it was done before) can have
detrimental effects, especially if R is small.
Signed-off-by: NIan McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

This is in response to a request sent earlier by Eric W. Biederman
and replaces all sysctl numbers for net.dccp.default with CTL_UNNUMBERED.

It has been tested to compile and to work.

Commiter note: I've removed the use of CTL_UNNUMBERED, not setting .ctl_name
               sets it to 0, that is the what CTL_UNNUMBERED is, reason is
               to avoid unneeded source code cluttering.
Signed-off-by: NGerrit Renker  <gerrit@erg.abdn.ac.uk>
Signed-off-by: NIan McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

[acme@newtoy net-2.6.20]$ pahole /tmp/tcp_ipv6.o inet_protosw
/* /pub/scm/linux/kernel/git/acme/net-2.6.20/include/net/protocol.h:69 */
struct inet_protosw {
        struct list_head           list;                 /*     0     8 */
        short unsigned int         type;                 /*     8     2 */

        /* XXX 2 bytes hole, try to pack */

        int                        protocol;             /*    12     4 */
        struct proto *             prot;                 /*    16     4 */
        const struct proto_ops  *  ops;                  /*    20     4 */
        int                        capability;           /*    24     4 */
        char                       no_check;             /*    28     1 */
        unsigned char              flags;                /*    29     1 */
}; /* size: 32, sum members: 28, holes: 1, sum holes: 2, padding: 2 */

So that we can kill that hole, protocol can only go all the way to 255 (RAW).
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

As this struct is not userland visible at all.
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

With this we eliminate the last hole in struct tcp_sock.

End result:

[acme@newtoy net-2.6.20]$ codiff -sV /tmp/tcp.o.before net/ipv4/tcp.o
/pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv4/tcp.c:
  struct tcp_sock |   -4
    tcp_header_len;
     from: int                   /*  1000(0)     4(0) */
     to:   u16                   /*  1000(0)     2(0) */
 1 struct changed
[acme@newtoy net-2.6.20]$

Now sizeof(tcp_sock) is just...

[acme@newtoy net-2.6.20]$ pahole --sizes ../OUTPUT/qemu/net-2.6.20/net/ipv4/tcp.o | grep -w tcp_sock
struct tcp_sock: 1500 0

1500 bytes ;-)
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

This patch
 * removes setting t_RTO in ccid3_hc_tx_init (per [RFC 3448, 4.2], t_RTO is
   undefined until feedback has been received);

 * makes some trivial changes (updates of comments);

 * performs a small optimisation by exploiting that the feedback timeout
   uses the value of t_ipi. The way it is done is safe, because the timeouts
   appear after the changes to t_ipi, ensuring that up-to-date values are used;

 * in ccid3_hc_tx_packet_recv, moves the t_rto statement closer to the calculation
   of the next_tmout. This makes the code clearer to read and is also safe, since
   t_rto is not updated until the next call of ccid3_hc_tx_packet_recv, and is not
   read by the functions called via ccid_wait_for_ccid();

 * removes a `max' statement in sk_reset_timer, this is not needed since the timeout
   value is always greater than 1E6 microseconds.

 * adds `XXX'es to highlight that currently the nofeedback timer is set
   in a non-standard way
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: NIan McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

This patch:

 * consolidates updating of parameters (t_nom, t_ipi, t_delta) which
   need to be updated at the same time, since they are inter-dependent

 * removes two inline functions which are no longer needed as a result of
   the above consolidation

 * resolves a FIXME regarding the re-calculation of t_ipi within the nofeedback
   timer, in the state where no feedback has previously been received

 * ties updating these parameters to updating the sending rate X, exploiting
   that all three parameters in turn depend on X; and using a small optimisation
   which can reduce the number of required instructions: only update the three
   parameters when X really changes
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: NIan McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

This patch concerns updating the value of the nofeedback timer when no feedback
has been received so far.

Since in this case the value of R is still undefined according to [RFC 3448,
4.2], we can not perform step (3) of [RFC 3448, 4.3].  A clarification is
provided in [RFC 4342, sec. 5], which states that in these cases the nofeedback
timer (still) expires "after two seconds".

Many thanks to Ian McDonald for pointing this out and providing the
clarification.

The patch
  * implements [RFC 4342, sec. 5] with regard to the above case
  * consolidates handling timer restart by
	- adding an appropriate jump label and
	- initialising the timeout value
Acked-by: NIan McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: NGerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

Caught by the EyeBalls(tm) of Thomas Graf
Signed-off-by: NJamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Might as well make flush notifier prettier when subpolicy used
Signed-off-by: NJamal Hadi Salim <hadi@cyberus.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

[acme@newtoy net-2.6.20]$ pahole net/ipv4/tcp.o xfrm_policy
/* /pub/scm/linux/kernel/git/acme/net-2.6.20/include/linux/security.h:67 */
struct xfrm_policy {
        struct xfrm_policy *       next;                 /*     0     4 */
        struct hlist_node          bydst;                /*     4     8 */
        struct hlist_node          byidx;                /*    12     8 */
        rwlock_t                   lock;                 /*    20    36 */
        atomic_t                   refcnt;               /*    56     4 */
        struct timer_list          timer;                /*    60    24 */
        u8                         type;                 /*    84     1 */

        /* XXX 3 bytes hole, try to pack */

        u32                        priority;             /*    88     4 */
        u32                        index;                /*    92     4 */
        struct xfrm_selector       selector;             /*    96    56 */
        struct xfrm_lifetime_cfg   lft;                  /*   152    64 */
        struct xfrm_lifetime_cur   curlft;               /*   216    32 */
        struct dst_entry *         bundles;              /*   248     4 */
        __u16                      family;               /*   252     2 */
        __u8                       action;               /*   254     1 */
        __u8                       flags;                /*   255     1 */
        __u8                       dead;                 /*   256     1 */
        __u8                       xfrm_nr;              /*   257     1 */

        /* XXX 2 bytes hole, try to pack */

        struct xfrm_sec_ctx *      security;             /*   260     4 */
        struct xfrm_tmpl           xfrm_vec[6];          /*   264   360 */
}; /* size: 624, sum members: 619, holes: 2, sum holes: 5 */

So lets have just one hole instead of two, by moving 'type' to just before 'action',
end result:

[acme@newtoy net-2.6.20]$ codiff -s /tmp/tcp.o.before net/ipv4/tcp.o
/pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv4/tcp.c:
  struct xfrm_policy |   -4
 1 struct changed
[acme@newtoy net-2.6.20]$

[acme@newtoy net-2.6.20]$ pahole -c 64 net/ipv4/tcp.o xfrm_policy
/* /pub/scm/linux/kernel/git/acme/net-2.6.20/include/linux/security.h:67 */
struct xfrm_policy {
        struct xfrm_policy *       next;                 /*     0     4 */
        struct hlist_node          bydst;                /*     4     8 */
        struct hlist_node          byidx;                /*    12     8 */
        rwlock_t                   lock;                 /*    20    36 */
        atomic_t                   refcnt;               /*    56     4 */
        struct timer_list          timer;                /*    60    24 */
        u32                        priority;             /*    84     4 */
        u32                        index;                /*    88     4 */
        struct xfrm_selector       selector;             /*    92    56 */
        struct xfrm_lifetime_cfg   lft;                  /*   148    64 */
        struct xfrm_lifetime_cur   curlft;               /*   212    32 */
        struct dst_entry *         bundles;              /*   244     4 */
        u16                        family;               /*   248     2 */
        u8                         type;                 /*   250     1 */
        u8                         action;               /*   251     1 */
        u8                         flags;                /*   252     1 */
        u8                         dead;                 /*   253     1 */
        u8                         xfrm_nr;              /*   254     1 */

        /* XXX 1 byte hole, try to pack */

        struct xfrm_sec_ctx *      security;             /*   256     4 */
        struct xfrm_tmpl           xfrm_vec[6];          /*   260   360 */
}; /* size: 620, sum members: 619, holes: 1, sum holes: 1 */

Are there any fugly data dependencies here? None that I know.

In the process changed the removed the __ prefixed types, that are just for
userspace visible headers.
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

[acme@newtoy net-2.6.20]$ pahole net/ipv4/tcp.o hh_cache
/* /pub/scm/linux/kernel/git/acme/net-2.6.20/include/linux/netdevice.h:190 */
struct hh_cache {
        struct hh_cache *          hh_next;              /*     0     4 */
        atomic_t                   hh_refcnt;            /*     4     4 */
        __be16                     hh_type;              /*     8     2 */

        /* XXX 2 bytes hole, try to pack */

        int                        hh_len;               /*    12     4 */
        int                        (*hh_output)();       /*    16     4 */
        rwlock_t                   hh_lock;              /*    20    36 */
        long unsigned int          hh_data[24];          /*    56    96 */
}; /* size: 152, sum members: 150, holes: 1, sum holes: 2 */

[acme@newtoy net-2.6.20]$ find net -name "*.[ch]" | xargs grep 'hh_len.\+=' | sort -u
net/atm/br2684.c:               hh->hh_len = PADLEN + ETH_HLEN;
net/ethernet/eth.c:     hh->hh_len = ETH_HLEN;
net/ipv4/ipconfig.c:    int hh_len = LL_RESERVED_SPACE(dev);
net/ipv4/ip_output.c:   hh_len = LL_RESERVED_SPACE(rt->u.dst.dev);
net/ipv4/ip_output.c:   int hh_len = LL_RESERVED_SPACE(dev);
net/ipv4/netfilter.c:   hh_len = (*pskb)->dst->dev->hard_header_len;
net/ipv4/raw.c: hh_len = LL_RESERVED_SPACE(rt->u.dst.dev);
net/ipv6/ip6_output.c:  hh_len = LL_RESERVED_SPACE(rt->u.dst.dev);
net/ipv6/netfilter/ip6t_REJECT.c:       hh_len = (dst->dev->hard_header_len + 15)&~15;
net/ipv6/raw.c: hh_len = LL_RESERVED_SPACE(rt->u.dst.dev);
[acme@newtoy net-2.6.20]$

[acme@newtoy net-2.6.20]$ find include -name "*.h" | xargs grep 'define ETH_HLEN'
include/linux/if_ether.h:#define ETH_HLEN       14              /* Total octets in header.       */

        (((dev)->hard_header_len&~(HH_DATA_MOD - 1)) + HH_DATA_MOD)

[acme@newtoy net-2.6.20]$ pahole net/ipv4/tcp.o net_device | grep hard_header_len
        short unsigned int         hard_header_len;      /*   106     2 */
[acme@newtoy net-2.6.20]$

So I think we're safe in turning hh_len an u16, end result:

[acme@newtoy net-2.6.20]$ codiff -sV /tmp/tcp.o.before net/ipv4/tcp.o
/pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv4/tcp.c:
  struct hh_cache |   -4
    hh_len;
     from: int                   /*    12(0)     4(0) */
     to:   u16                   /*    10(0)     2(0) */
 1 struct changed
[acme@newtoy net-2.6.20]$
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

We have a hole in:

[acme@newtoy net-2.6.20]$ pahole net/ipv6/tcp_ipv6.o inet_connection_sock_af_ops
/* /pub/scm/linux/kernel/git/acme/net-2.6.20/include/net/inet_connection_sock.h:38 */
struct inet_connection_sock_af_ops {
        int                        (*queue_xmit)();      /*     0     4 */
        void                       (*send_check)();      /*     4     4 */
        int                        (*rebuild_header)();  /*     8     4 */
        int                        (*conn_request)();    /*    12     4 */
        struct sock *              (*syn_recv_sock)();   /*    16     4 */
        int                        (*remember_stamp)();  /*    20     4 */
        __u16                      net_header_len;       /*    24     2 */

        /* XXX 2 bytes hole, try to pack */

        int                        (*setsockopt)();      /*    28     4 */
        int                        (*getsockopt)();      /*    32     4 */
        int                        (*compat_setsockopt)(); /*    36     4 */
        int                        (*compat_getsockopt)(); /*    40     4 */
        void                       (*addr2sockaddr)();   /*    44     4 */
        int                        sockaddr_len;         /*    48     4 */
}; /* size: 52, sum members: 50, holes: 1, sum holes: 2 */

But we don't need sockaddr_len to be an int:

[acme@newtoy net-2.6.20]$ find net -name "*.[ch]" | xargs grep '\.sockaddr_len.\+=' | sort -u
net/dccp/ipv4.c:        .sockaddr_len      = sizeof(struct sockaddr_in),
net/dccp/ipv6.c:        .sockaddr_len      = sizeof(struct sockaddr_in6),
net/ipv4/tcp_ipv4.c:    .sockaddr_len      = sizeof(struct sockaddr_in),
net/ipv6/tcp_ipv6.c:    .sockaddr_len      = sizeof(struct sockaddr_in6),
net/sctp/ipv6.c:        .sockaddr_len      = sizeof(struct sockaddr_in6),
net/sctp/protocol.c:    .sockaddr_len      = sizeof(struct sockaddr_in),

[acme@newtoy net-2.6.20]$ pahole --sizes net/ipv6/tcp_ipv6.o | grep sockaddr_in
struct sockaddr_in: 16 0
struct sockaddr_in6: 28 0
[acme@newtoy net-2.6.20]$

So I turned sockaddr_len a 'u16', and now:

[acme@newtoy net-2.6.20]$ pahole net/ipv6/tcp_ipv6.o inet_connection_sock_af_ops
/* /pub/scm/linux/kernel/git/acme/net-2.6.20/include/net/inet_connection_sock.h:38 */
struct inet_connection_sock_af_ops {
        int            (*queue_xmit)();        /*     0   4 */
        void           (*send_check)();        /*     4   4 */
        int            (*rebuild_header)();    /*     8   4 */
        int            (*conn_request)();      /*    12   4 */
        struct sock *  (*syn_recv_sock)();     /*    16   4 */
        int            (*remember_stamp)();    /*    20   4 */
        u16            net_header_len;         /*    24   2 */
        u16            sockaddr_len;           /*    26   2 */
        int            (*setsockopt)();        /*    28   4 */
        int            (*getsockopt)();        /*    32   4 */
        int            (*compat_setsockopt)(); /*    36   4 */
        int            (*compat_getsockopt)(); /*    40   4 */
        void           (*addr2sockaddr)();     /*    44   4 */
}; /* size: 48 */

So we've saved 4 bytes:

[acme@newtoy net-2.6.20]$ codiff -sV /tmp/tcp_ipv6.o.before net/ipv6/tcp_ipv6.o
/pub/scm/linux/kernel/git/acme/net-2.6.20/net/ipv6/tcp_ipv6.c:
  struct inet_connection_sock_af_ops |   -4
    net_header_len;
     from: __u16                 /*    24(0)     2(0) */
     to:   u16                   /*    24(0)     2(0) */
    sockaddr_len;
     from: int                   /*    48(0)     4(0) */
     to:   u16                   /*    26(0)     2(0) */
 1 struct changed
[acme@newtoy net-2.6.20]$
Signed-off-by: NArnaldo Carvalho de Melo <acme@mandriva.com>

This patch consolidates set/getsockopt code between UDP(-Lite) v4 and 6. The
justification is that UDP(-Lite) is a transport-layer protocol and therefore
the socket option code (at least in theory) should be AF-independent.

Furthermore, there is the following code reduplication:
 * do_udp{,v6}_getsockopt is 100% identical between v4 and v6
 * do_udp{,v6}_setsockopt is identical up to the following differerence
	--v4 in contrast to v4 additionally allows the experimental encapsulation
          types  UDP_ENCAP_ESPINUDP and UDP_ENCAP_ESPINUDP_NON_IKE
	--the remainder is identical between v4 and v6
   I believe that this difference is of little relevance.

The advantages in not duplicating twice almost completely identical code.

The patch further simplifies the interface of udp{,v6}_push_pending_frames,
since for the second argument (struct udp_sock *up) it always holds that
up = udp_sk(sk); where sk is the first function argument.
Signed-off-by: NGerrit Renker  <gerrit@erg.abdn.ac.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

IPv4, IPv6, and DECNet all use struct rta_cacheinfo in a similiar
way, therefore rtnl_put_cacheinfo() is added to reuse code.
Signed-off-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>