This way ip_output.c no longer needs rt->rt_{src,dst}.

We already have these keys sitting, ready and waiting, on the stack or
in a socket structure.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We have two cases.

Either the socket is in TCP_ESTABLISHED state and connect() filled
in the inet socket cork flow, or we looked up the route here and
used an on-stack flow.

Track which one it was, and use it to obtain src/dst addrs.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

Now we can pick it out of the provided flow key.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This allows us to acquire the exact route keying information from the
protocol, however that might be managed.

It handles all of the possibilities, from the simplest case of storing
the key in inet->cork.fl to the more complex setup SCTP has where
individual transports determine the flow.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Operation order is now transposed, we first create the child
socket then we try to hook up the route.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is just like inet_csk_route_req() except that it operates after
we've created the new child socket.

In this way we can use the new socket's cork flow for proper route
key storage.

This will be used by DCCP and TCP child socket creation handling.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

All invokers of ip_queue_xmit() must make certain that the
socket is locked.  All of SCTP, TCP, DCCP, and L2TP now make
sure this is the case.

Therefore we can use the cork flow during output route lookup in
ip_queue_xmit() when the socket route check fails.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These two functions must be invoked only when the socket is locked
(because socket identity modifications are made non-atomically).

Therefore we can use the cork flow for output route lookups.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is to make sure that an l2tp socket's inet cork flow is
fully filled in, when it's encapsulated in UDP.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since this is invoked from inet_stream_connect() the socket is locked
and therefore this usage is safe.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Noticed by Joe Perches.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ip_setup_cork() explicitly initializes every member of
inet_cork except flags, addr, and opt.  So we can simply
set those three members to zero instead of using a
memset() via an empty struct assignment.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NEric Dumazet <eric.dumazet@gmail.com>

When we fast path datagram sends to avoid locking by putting
the inet_cork on the stack we use up lots of space that isn't
necessary.

This is because inet_cork contains a "struct flowi" which isn't
used in these code paths.

Split inet_cork to two parts, "inet_cork" and "inet_cork_full".
Only the latter of which has the "struct flowi" and is what is
stored in inet_sock.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NEric Dumazet <eric.dumazet@gmail.com>

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

The possibility to call dev_alloc_name in advance remains.

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

Commit 4a94445c (net: Use ip_route_input_noref() in input path)
added a bug in IP defragmentation handling, in case timeout is fired.

When a frame is defragmented, we use last skb dst field when building
final skb. Its dst is valid, since we are in rcu read section.

But if a timeout occurs, we take first queued fragment to build one ICMP
TIME EXCEEDED message. Problem is all queued skb have weak dst pointers,
since we escaped RCU critical section after their queueing. icmp_send()
might dereference a now freed (and possibly reused) part of memory.

Calling skb_dst_drop() and ip_route_input_noref() to revalidate route is
the only possible choice.
Reported-by: NDenys Fedoryshchenko <denys@visp.net.lb>
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

First, make callers pass on-stack flowi4 to ip_route_output_gre()
so they can get at the fully resolved flow key.

Next, use that in ipgre_tunnel_xmit() to avoid the need to use
rt->rt_{dst,src}.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This eliminates the need to use rt->rt_{src,dst}.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of rt->rt_{dst,src}

The only tricky part is source route option handling.

If the source route option is enabled we can't just use plain 'daddr',
we have to use opt->opt.faddr.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of rt->rt_{dst,src}
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of rt->rt_{src,dst}
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

To more accurately reflect that it is purely a routing
cache lookup key and is used in no other context.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use information from the skb as much as possible, currently
this means daddr, saddr, and TOS.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ctl_table_headers registered with register_net_sysctl_table should
have been unregistered with the equivalent unregister_net_sysctl_table
Signed-off-by: NLucian Adrian Grijincu <lucian.grijincu@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Slow path output route resolution always makes sure that
->{saddr,daddr} are set, and also if we trigger into IPSEC resolution
we initialize them as well, because xfrm_lookup() expects them to be
fully resolved.

But if we hit the fast path and flowi4->flowi4_proto is zero, we won't
do this initialization.

Therefore, move the IPSEC path initialization to the route cache
lookup fast path to make sure these are always set.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

fib_trie_table() is called during netns creation and
Chromium uses clone(CLONE_NEWNET) to sandbox renderer process.

Don't print anything.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For backward compatibility, we should retain the module parameters and
sysfs attributes to control the number of peer notifications
(gratuitous ARPs and unsolicited NAs) sent after bonding failover.
Also, it is possible for failover to take place even though the new
active slave does not have link up, and in that case the peer
notification should be deferred until it does.

Change ipv4 and ipv6 so they do not automatically send peer
notifications on bonding failover.

Change the bonding driver to send separate NETDEV_NOTIFY_PEERS
notifications when the link is up, as many times as requested.  Since
it does not directly control which protocols send notifications, make
num_grat_arp and num_unsol_na aliases for a single parameter.  Bump
the bonding version number and update its documentation.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Signed-off-by: NJay Vosburgh <fubar@us.ibm.com>
Acked-by: NBrian Haley <brian.haley@hp.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that output route lookups update the flow with
destination address selection, we can fetch it from
fl4->daddr instead of rt->rt_dst
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that output route lookups update the flow with
destination address selection, we can fetch it from
fl4->daddr instead of rt->rt_dst
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that output route lookups update the flow with
destination address selection, we can fetch it from
fl4->daddr instead of rt->rt_dst
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that output route lookups update the flow with
source address selection, we can fetch it from
fl4->saddr instead of rt->rt_src
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that output route lookups update the flow with
source address selection, we can fetch it from
fl4->saddr instead of rt->rt_src
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that output route lookups update the flow with
source address selection, we can fetch it from
fl4->saddr instead of rt->rt_src
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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

Make dst_alloc() and it's users explicitly initialize the entire
entry.

The zero'ing done by kmem_cache_zalloc() was almost entirely
redundant.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now the dst->dev, dev->obsolete, and dst->flags values can
be specified as well.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We lack proper synchronization to manipulate inet->opt ip_options

Problem is ip_make_skb() calls ip_setup_cork() and
ip_setup_cork() possibly makes a copy of ipc->opt (struct ip_options),
without any protection against another thread manipulating inet->opt.

Another thread can change inet->opt pointer and free old one under us.

Use RCU to protect inet->opt (changed to inet->inet_opt).

Instead of handling atomic refcounts, just copy ip_options when
necessary, to avoid cache line dirtying.

We cant insert an rcu_head in struct ip_options since its included in
skb->cb[], so this patch is large because I had to introduce a new
ip_options_rcu structure.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Output route resolution never returns a route with rt_src set to zero
(which is INADDR_ANY).

Even if the flow key for the output route lookup specifies INADDR_ANY
for the source address, the output route resolution chooses a real
source address to use in the final route.

This test has existed forever in igmp_send_report() and David Stevens
simply copied over the erroneous test when implementing support for
IGMPv3.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Reviewed-by: NEric Dumazet <eric.dumazet@gmail.com>

These functions are used together as a unit for route resolution
during connect().  They address the chicken-and-egg problem that
exists when ports need to be allocated during connect() processing,
yet such port allocations require addressing information from the
routing code.

It's currently more heavy handed than it needs to be, and in
particular we allocate and initialize a flow object twice.

Let the callers provide the on-stack flow object.  That way we only
need to initialize it once in the ip_route_connect() call.

Later, if ip_route_newports() needs to do anything, it re-uses that
flow object as-is except for the ports which it updates before the
route re-lookup.

Also, describe why this set of facilities are needed and how it works
in a big comment.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Reviewed-by: NEric Dumazet <eric.dumazet@gmail.com>