The inner headers are invalid after a xfrm transformation.
So reset the skb encapsulation field to ensure nobody tries
to access the inner headers.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Skb_gso_segment() uses skb control block during segmentation.
This patch adds 32-bytes room for previous control block which
will be copied into all resulting segments.

This patch fixes kernel crash during fragmenting forwarded packets.
Fragmentation requires valid IP CB in skb for clearing ip options.
Also patch removes custom save/restore in ovs code, now it's redundant.
Signed-off-by: NKonstantin Khlebnikov <koct9i@gmail.com>
Link: http://lkml.kernel.org/r/CALYGNiP-0MZ-FExV2HutTvE9U-QQtkKSoE--KN=JQE5STYsjAA@mail.gmail.comSigned-off-by: NDavid S. Miller <davem@davemloft.net>

XFRM can deal with SYNACK messages, sent while listener socket
is not locked. We add proper rcu protection to __xfrm_sk_clone_policy()
and xfrm_sk_policy_lookup()

This might serve as the first step to remove xfrm.xfrm_policy_lock
use in fast path.

Fixes: fa76ce73 ("inet: get rid of central tcp/dccp listener timer")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We will soon switch sk->sk_policy[] to RCU protection,
as SYNACK packets are sent while listener socket is not locked.

This patch simply adds RCU grace period before struct xfrm_policy
freeing, and the corresponding rcu_head in struct xfrm_policy.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

TCP SYNACK messages might now be attached to request sockets.

XFRM needs to get back to a listener socket.

Adds new helpers that might be used elsewhere :
sk_to_full_sk() and sk_const_to_full_sk()

Note: We also need to add RCU protection for xfrm lookups,
now TCP/DCCP have lockless listener processing. This will
be addressed in separate patches.

Fixes: ca6fb065 ("tcp: attach SYNACK messages to request sockets instead of listener")
Reported-by: NDave Jones <davej@codemonkey.org.uk>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove the dst_entries_init/destroy calls for xfrm4 and xfrm6 dst_ops
templates; their dst_entries counters will never be used.  Move the
xfrm dst_ops initialization from the common xfrm/xfrm_policy.c to
xfrm4/xfrm4_policy.c and xfrm6/xfrm6_policy.c, and call dst_entries_init
and dst_entries_destroy for each net namespace.

The ipv4 and ipv6 xfrms each create dst_ops template, and perform
dst_entries_init on the templates.  The template values are copied to each
net namespace's xfrm.xfrm*_dst_ops.  The problem there is the dst_ops
pcpuc_entries field is a percpu counter and cannot be used correctly by
simply copying it to another object.

The result of this is a very subtle bug; changes to the dst entries
counter from one net namespace may sometimes get applied to a different
net namespace dst entries counter.  This is because of how the percpu
counter works; it has a main count field as well as a pointer to the
percpu variables.  Each net namespace maintains its own main count
variable, but all point to one set of percpu variables.  When any net
namespace happens to change one of the percpu variables to outside its
small batch range, its count is moved to the net namespace's main count
variable.  So with multiple net namespaces operating concurrently, the
dst_ops entries counter can stray from the actual value that it should
be; if counts are consistently moved from one net namespace to another
(which my testing showed is likely), then one net namespace winds up
with a negative dst_ops count while another winds up with a continually
increasing count, eventually reaching its gc_thresh limit, which causes
all new traffic on the net namespace to fail with -ENOBUFS.
Signed-off-by: NDan Streetman <dan.streetman@canonical.com>
Signed-off-by: NDan Streetman <ddstreet@ieee.org>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Increment the LINUX_MIB_XFRMINSTATEMODEERROR statistic counter
to notify about dropped packets if we fail to fetch a inner mode.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

On sparc, deleting established SAs (e.g., by restarting ipsec)
results in unaligned access messages via xfrm_del_sa ->
km_state_notify -> xfrm_send_state_notify().

Even though struct xfrm_usersa_info is aligned on 8-byte boundaries,
netlink attributes are fundamentally only 4 byte aligned, and this
cannot be changed for nla_data() that is passed up to userspace.
As a result, the put_unaligned() macro needs to be used to
set up potentially unaligned fields such as the xfrm_stats in
copy_to_user_state()
Signed-off-by: NSowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

The network namespace is already passed into dst_output pass it into
dst->output lwt->output and friends.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For consistency with the other similar methods in the kernel pass a
struct sock into the dst_ops .local_out method.

Simplifying the socket passing case is needed a prequel to passing a
struct net reference into .local_out.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Replace dst_output_okfn with dst_output
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allow to change the replay threshold (XFRMA_REPLAY_THRESH) and expiry
timer (XFRMA_ETIMER_THRESH) of a state without having to set other
attributes like replay counter and byte lifetime. Changing these other
values while traffic flows will break the state.
Signed-off-by: NMichael Rossberg <michael.rossberg@tu-ilmenau.de>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Very soon, TCP stack might call inet_csk_route_req(), which
calls inet_csk_route_req() with an unlocked listener socket,
so we need to make sure ip_route_output_flow() is not trying to
change any field from its socket argument.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In code review it was noticed that I had failed to add some blank lines
in places where they are customarily used.  Taking a second look at the
code I have to agree blank lines would be nice so I have added them
here.
Reported-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is immediately motivated by the bridge code that chains functions that
call into netfilter.  Without passing net into the okfns the bridge code would
need to guess about the best expression for the network namespace to process
packets in.

As net is frequently one of the first things computed in continuation functions
after netfilter has done it's job passing in the desired network namespace is in
many cases a code simplification.

To support this change the function dst_output_okfn is introduced to
simplify passing dst_output as an okfn.  For the moment dst_output_okfn
just silently drops the struct net.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass a network namespace parameter into the netfilter hooks.  At the
call site of the netfilter hooks the path a packet is taking through
the network stack is well known which allows the network namespace to
be easily and reliabily.

This allows the replacement of magic code like
"dev_net(state->in?:state->out)" that appears at the start of most
netfilter hooks with "state->net".

In almost all cases the network namespace passed in is derived
from the first network device passed in, guaranteeing those
paths will not see any changes in practice.

The exceptions are:
xfrm/xfrm_output.c:xfrm_output_resume()         xs_net(skb_dst(skb)->xfrm)
ipvs/ip_vs_xmit.c:ip_vs_nat_send_or_cont()      ip_vs_conn_net(cp)
ipvs/ip_vs_xmit.c:ip_vs_send_or_cont()          ip_vs_conn_net(cp)
ipv4/raw.c:raw_send_hdrinc()                    sock_net(sk)
ipv6/ip6_output.c:ip6_xmit()			sock_net(sk)
ipv6/ndisc.c:ndisc_send_skb()                   dev_net(skb->dev) not dev_net(dst->dev)
ipv6/raw.c:raw6_send_hdrinc()                   sock_net(sk)
br_netfilter_hooks.c:br_nf_pre_routing_finish() dev_net(skb->dev) before skb->dev is set to nf_bridge->physindev

In all cases these exceptions seem to be a better expression for the
network namespace the packet is being processed in then the historic
"dev_net(in?in:out)".  I am documenting them in case something odd
pops up and someone starts trying to track down what happened.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a sock paramter to dst_output making dst_output_sk superfluous.
Add a skb->sk parameter to all of the callers of dst_output
Have the callers of dst_output_sk call dst_output.
Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Now that seqniv is identical with seqiv we no longer need it.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>

Rules can be installed that direct route lookups to specific tables based
on oif. Plumb the oif through the xfrm lookups so it gets set in the flow
struct and passed to the resolver routines.
Signed-off-by: NDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

The patch was generated using fixed coccinelle semantic patch
scripts/coccinelle/api/memdup.cocci [1].

[1]: http://permalink.gmane.org/gmane.linux.kernel/2014320Signed-off-by: NAndrzej Hajda <a.hajda@samsung.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

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

Signed-off-by: NMartin Willi <martin@strongswan.org>
Acked-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This change makes it so that if a tunnel is defined we just use the mark
from the tunnel instead of the mark from the skb header.  By doing this we
can avoid the need to set skb->mark inside of the tunnel receive functions.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

This patch adds IV generator information to xfrm_state.  This
is currently obtained from our own list of algorithm descriptions.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

This patch adds IV generator information for each AEAD and block
cipher to xfrm_algo_desc.  This will be used to access the new
AEAD interface.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>

As we're now always including the high bits of the sequence number
in the IV generation process we need to ensure that they don't
contain crap.

This patch ensures that the high sequence bits are always zeroed
so that we don't leak random data into the IV.
Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

The policies are organized into list by priority ascent of policy,
so it is unnecessary to continue to loop the policy if the priority
of current looped police is larger than or equal priority which is
from the policy_bydst list.

This allows to match policy with ~0U priority in inexact list too.
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

As xfrm_output_one() is the only caller of skb_dst_pop(), we should
make skb_dst_pop() localized.
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

if hold_queue of old xfrm_policy is NULL, return directly, then not need to
run other codes, especially take the spin lock
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

xfrm_pol_hold will check its input with NULL
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

The returned xfrm_state should be hold before unlock xfrm_state_lock,
otherwise the returned xfrm_state maybe be released.

Fixes: c454997e[{pktgen, xfrm} Introduce xfrm_state_lookup_byspi..]
Cc: Fan Du <fan.du@intel.com>
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Acked-by: NFan Du <fan.du@intel.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

Check x->km.state with XFRM_STATE_ACQ only when state is not
XFRM_STAT_VALID, not everytime
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

If xfrm_*_register_afinfo failed since xfrm_*_afinfo[afinfo->family] had the
value, return the -EEXIST, not -ENOBUFS
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

The walk from input is the list header, and marked as dead, and will
be skipped in loop.

list_first_entry() can be used to return the true usable value from
walk if walk is not empty
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Acked-by: NHerbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

The task of xfrm_queue_purge is same as skb_queue_purge, so remove it
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

On the output paths in particular, we have to sometimes deal with two
socket contexts.  First, and usually skb->sk, is the local socket that
generated the frame.

And second, is potentially the socket used to control a tunneling
socket, such as one the encapsulates using UDP.

We do not want to disassociate skb->sk when encapsulating in order
to fix this, because that would break socket memory accounting.

The most extreme case where this can cause huge problems is an
AF_PACKET socket transmitting over a vxlan device.  We hit code
paths doing checks that assume they are dealing with an ipv4
socket, but are actually operating upon the AF_PACKET one.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

https://bugzilla.kernel.org/show_bug.cgi?id=95211

Commit 70be6c91
("xfrm: Add xfrm_tunnel_skb_cb to the skb common buffer") added check
which dereferences ->outer_mode too early but larval SAs don't have
this pointer set (yet). So check for tunnel stuff later.

Mike Noordermeer reported this bug and patiently applied all the debugging.

Technically this is remote-oops-in-interrupt-context type of thing.

BUG: unable to handle kernel NULL pointer dereference at 0000000000000034
IP: [<ffffffff8150dca2>] xfrm_input+0x3c2/0x5a0
	...
[<ffffffff81500fc6>] ? xfrm4_esp_rcv+0x36/0x70
[<ffffffff814acc9a>] ? ip_local_deliver_finish+0x9a/0x200
[<ffffffff81471b83>] ? __netif_receive_skb_core+0x6f3/0x8f0
	...

RIP  [<ffffffff8150dca2>] xfrm_input+0x3c2/0x5a0
Kernel panic - not syncing: Fatal exception in interrupt
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>