In order to enable lockdep on seqcount/seqlock structures, we
must explicitly initialize any locks.

The u64_stats_sync structure, uses a seqcount, and thus we need
to introduce a u64_stats_init() function and use it to initialize
the structure.

This unfortunately adds a lot of fairly trivial initialization code
to a number of drivers. But the benefit of ensuring correctness makes
this worth while.

Because these changes are required for lockdep to be enabled, and the
changes are quite trivial, I've not yet split this patch out into 30-some
separate patches, as I figured it would be better to get the various
maintainers thoughts on how to best merge this change along with
the seqcount lockdep enablement.

Feedback would be appreciated!
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
Acked-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NPeter Zijlstra <peterz@infradead.org>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: James Morris <jmorris@namei.org>
Cc: Jesse Gross <jesse@nicira.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Mirko Lindner <mlindner@marvell.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Roger Luethi <rl@hellgate.ch>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Simon Horman <horms@verge.net.au>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Wensong Zhang <wensong@linux-vs.org>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/1381186321-4906-2-git-send-email-john.stultz@linaro.orgSigned-off-by: NIngo Molnar <mingo@kernel.org>

When queueing the netdevices for removal, we queue the
fallback device twice in ip_tunnel_destroy(). The first
time when we queue all netdevices in the namespace and
then again explicitly. Fix this by removing the explicit
queueing of the fallback device.

Bug was introduced when network namespace support was added
with commit 6c742e71 ("ipip: add x-netns support").

Cc: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Acked-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently we can not update the tunnel parameters of
the fallback tunnels because we don't find them in the
hash lists. Fix this by adding them on initialization.

Bug was introduced with commit c5441932
("GRE: Refactor GRE tunneling code.")

Cc: Pravin Shelar <pshelar@nicira.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We might extend the used aera of a skb beyond the total
headroom when we install the ipip header. Fix this by
calling skb_cow_head() unconditionally.

Bug was introduced with commit c5441932
("GRE: Refactor GRE tunneling code.")

Cc: Pravin Shelar <pshelar@nicira.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

While sending packet skb_cow_head() can change skb header which
invalidates inner_iph pointer to skb header. Following patch
avoid using it. Found by code inspection.

This bug was introduced by commit 0e6fbc5b (ip_tunnels: extend
iptunnel_xmit()).
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The goal of this patch is to harmonize cleanup done on a skbuff on rx path.
Before this patch, behaviors were different depending of the tunnel type.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The goal of this patch is to harmonize cleanup done on a skbuff on xmit path.
Before this patch, behaviors were different depending of the tunnel type.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This function was only used when a packet was sent to another netns. Now, it can
also be used after tunnel encapsulation or decapsulation.

Only skb_orphan() should not be done when a packet is not crossing netns.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This argument is not used, let's remove it.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Eric Dumazet says that my previous fix for an ERR_PTR dereference
(ea857f28 'ipip: dereferencing an ERR_PTR in ip_tunnel_init_net()')
could be racy and suggests the following fix instead.
Reported-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to move the derefernce after the IS_ERR() check.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch allows to switch the netns when packet is encapsulated or
decapsulated. In other word, the encapsulated packet is received in a netns,
where the lookup is done to find the tunnel. Once the tunnel is found, the
packet is decapsulated and injecting into the corresponding interface which
stands to another netns.

When one of the two netns is removed, the tunnel is destroyed.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It's better to use available helpers for these tests.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

skb_scrub_packet() was called before eth_type_trans() to let eth_type_trans()
set pkt_type.

In fact, we should force pkt_type to PACKET_HOST, so move the call after
eth_type_trans().
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The IP tunnel hash heads can be embedded in the per-net structure
since it is a fixed size. Reduce the size so that the total structure
fits in a page size. The original size was overly large, even NETDEV_HASHBITS
is only 8 bits!

Also, add some white space for readability.
Signed-off-by: NStephen Hemminger <stephen@networkplumber.org>
Acked-by: Pravin B Shelar <pshelar@nicira.com>.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change fixes an MTU sizing issue seen with gretap tunnels when non-gso
packets are sent from the interface.

In my case I was able to reproduce the issue by simply sending a ping of
1421 bytes with the gretap interface created on a device with a standard
1500 mtu.

This fix is based on the fact that the tunnel mtu is already adjusted by
dev->hard_header_len so it would make sense that any packets being compared
against that mtu should also be adjusted by hard_header_len and the tunnel
header instead of just the tunnel header.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Reported-by: NCong Wang <amwang@redhat.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In path mtu check, ip header total length works for gre device
but not for gre-tap device.  Use skb len which is consistent
for all tunneling types.  This is old bug in gre.
This also fixes mtu calculation bug introduced by
commit c5441932 (GRE: Refactor GRE tunneling code).
Reported-by: NTimo Teras <timo.teras@iki.fi>
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch allows to switch the netns when packet is encapsulated or
decapsulated. In other word, the encapsulated packet is received in a netns,
where the lookup is done to find the tunnel. Once the tunnel is found, the
packet is decapsulated and injecting into the corresponding interface which
stands to another netns.

When one of the two netns is removed, the tunnel is destroyed.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since commit 32b8a8e5 "sit: add IPv4 over IPv4 support",
tunnel->parms.iph.protocol is 0 when both 4in4 and 6in4 are setup, but
xfrm_lookup() is called only when proto is != 0, thus we need to pass the real
value.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Process skb tunnel header before sending packet to protocol handler.
this allows code sharing between gre and ovs gre modules.
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Refactor various ip tunnels xmit functions and extend iptunnel_xmit()
so that there is more code sharing.
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If CONFIG_NET_NS is not set then __net_init is the same as __init and
__net_exit is the same as __exit. These functions will be removed from
memory after the module loads or is removed. Functions that are exported
for use by other functions should never be labeled for removal.

Bug introduced by commit c5441932
("GRE: Refactor GRE tunneling code.")
Reported-by: NSteinar H. Gunderson <sgunderson@bigfoot.com>
Signed-off-by: NSteven Rostedt <rostedt@goodmis.org>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Before this patch, ip_tunnel_xmit() was using the field protocol from the IP
header passed into argument.
There is no functional change, this patch prepares the support of IPv4 over
IPv4 for module sit.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Daniel Petre reported crashes in icmp_dst_unreach() with following call
graph:

#3 [ffff88003fc03938] __stack_chk_fail at ffffffff81037f77
#4 [ffff88003fc03948] icmp_send at ffffffff814d5fec
#5 [ffff88003fc03ae8] ipv4_link_failure at ffffffff814a1795
#6 [ffff88003fc03af8] ipgre_tunnel_xmit at ffffffff814e7965
#7 [ffff88003fc03b78] dev_hard_start_xmit at ffffffff8146e032
#8 [ffff88003fc03bc8] sch_direct_xmit at ffffffff81487d66
#9 [ffff88003fc03c08] __qdisc_run at ffffffff81487efd
#10 [ffff88003fc03c48] dev_queue_xmit at ffffffff8146e5a7
#11 [ffff88003fc03c88] ip_finish_output at ffffffff814ab596

Daniel found a similar problem mentioned in
 http://lkml.indiana.edu/hypermail/linux/kernel/1007.0/00961.html

And indeed this is the root cause : skb->cb[] contains data fooling IP
stack.

We must clear IPCB in ip_tunnel_xmit() sooner in case dst_link_failure()
is called. Or else skb->cb[] might contain garbage from GSO segmentation
layer.

A similar fix was tested on linux-3.9, but gre code was refactored in
linux-3.10. I'll send patches for stable kernels as well.

Many thanks to Daniel for providing reports, patches and testing !
Reported-by: NDaniel Petre <daniel.petre@rcs-rds.ro>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As Ben pointed out following patch fixes bug in checking device
name length limits while forming tunnel device name.

CC: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Following patch refactors GRE code into ip tunneling code and GRE
specific code. Common tunneling code is moved to ip_tunnel module.
ip_tunnel module is written as generic library which can be used
by different tunneling implementations.

ip_tunnel module contains following components:
 - packet xmit and rcv generic code. xmit flow looks like
   (gre_xmit/ipip_xmit)->ip_tunnel_xmit->ip_local_out.
 - hash table of all devices.
 - lookup for tunnel devices.
 - control plane operations like device create, destroy, ioctl, netlink
   operations code.
 - registration for tunneling modules, like gre, ipip etc.
 - define single pcpu_tstats dev->tstats.
 - struct tnl_ptk_info added to pass parsed tunnel packet parameters.

ipip.h header is renamed to ip_tunnel.h
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>