We drop a connection request if the accept backlog is full and there are
sufficient packets in the syn queue to warrant starting drops. Increment the
appropriate counters so this isn't silent, for accurate stats and help in
debugging.

This patch assumes LINUX_MIB_LISTENDROPS is a superset of/includes the
counter LINUX_MIB_LISTENOVERFLOWS.
Signed-off-by: NNivedita Singhvi <niv@us.ibm.com>
Acked-by: NVijay Subramanian <subramanian.vijay@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Due to IP_GRE GSO support, GRE can recieve non linear skb which
results in panic in case of GRE_CSUM.  Following patch fixes it by
using correct csum API.

Bug introduced in commit 6b78f16e (gre: add GSO support)
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>

git commit 9cb3a50c (ipv4: Invalidate the socket cached route on
pmtu events if possible) introduced a refcount problem. We don't
get a refcount on the route if we get it from__sk_dst_get(), but
we need one if we want to reuse this route because __sk_dst_set()
releases the refcount of the old route. This patch adds proper
refcount handling for that case. We introduce a 'new' flag to
indicate that we are going to use a new route and we release the
old route only if we replace it by a new one.
Reported-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This implements a socket release callback function to check
if the socket cached route got invalid during the time
we owned the socket. The function is used from udp, raw
and ping sockets.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The route lookup in ipv4_sk_update_pmtu() might return a route
different from the route we cached at the socket. This is because
standart routes are per cpu, so each cpu has it's own struct rtable.
This means that we do not invalidate the socket cached route if the
NET_RX_SOFTIRQ is not served by the same cpu that the sending socket
uses. As a result, the cached route reused until we disconnect.

With this patch we invalidate the socket cached route if possible.
If the socket is owened by the user, we can't update the cached
route directly. A followup patch will implement socket release
callback functions for datagram sockets to handle this case.
Reported-by: NYurij M. Plotnikov <Yurij.Plotnikov@oktetlabs.ru>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On IPsec pmtu events we can't access the transport headers of
the original packet, so we can't find the socket that sent
the packet. The only chance to notify the socket about the
pmtu change is to force a relookup for all routes. This
patch implenents this for the IPsec protocols.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

commit 563d34d0 (tcp: dont drop MTU reduction indications)
added an error leading to incorrect accounting of
LINUX_MIB_LOCKDROPPEDICMPS

If socket is owned by the user, we want to increment
this SNMP counter, unless the message is a
(ICMP_DEST_UNREACH,ICMP_FRAG_NEEDED) one.
Reported-by: NMaciej Żenczykowski <maze@google.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: NMaciej Żenczykowski <maze@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Routes with locked mtu should not use learned pmtu informations,
so do not update the pmtu on these routes.
Reported-by: NJulian Anastasov <ja@ssi.bg>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The output route check was introduced with git commit 261663b0
(ipv4: Don't use the cached pmtu informations for input routes)
during times when we cached the pmtu informations on the
inetpeer. Now the pmtu informations are back in the routes,
so this check is obsolete. It also had some unwanted side effects,
as reported by Timo Teras and Lukas Tribus.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Acked-by: NTimo Teräs <timo.teras@iki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit c3ae62af (tcp: should drop incoming frames without ACK flag
set) added a regression on the handling of RST messages.

RST should be allowed to come even without ACK bit set. We validate
the RST by checking the exact sequence, as requested by RFC 793 and
5961 3.2, in tcp_validate_incoming()
Reported-by: NEric Wong <normalperson@yhbt.net>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Tested-by: NEric Wong <normalperson@yhbt.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Under unusual circumstances, TCP collapse can split a big GRO TCP packet
while its being used in a splice(socket->pipe) operation.

skb_splice_bits() releases the socket lock before calling
splice_to_pipe().

[ 1081.353685] WARNING: at net/ipv4/tcp.c:1330 tcp_cleanup_rbuf+0x4d/0xfc()
[ 1081.371956] Hardware name: System x3690 X5 -[7148Z68]-
[ 1081.391820] cleanup rbuf bug: copied AD3BCF1 seq AD370AF rcvnxt AD3CF13

To fix this problem, we must eat skbs in tcp_recv_skb().

Remove the inline keyword from tcp_recv_skb() definition since
it has three call sites.
Reported-by: NChristian Becker <c.becker@traviangames.com>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Tested-by: NWilly Tarreau <w@1wt.eu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 02275a2e (tcp: don't abort splice() after small transfers)
added a regression.

[   83.843570] INFO: rcu_sched self-detected stall on CPU
[   83.844575] INFO: rcu_sched detected stalls on CPUs/tasks: { 6} (detected by 0, t=21002 jiffies, g=4457, c=4456, q=13132)
[   83.844582] Task dump for CPU 6:
[   83.844584] netperf         R  running task        0  8966   8952 0x0000000c
[   83.844587]  0000000000000000 0000000000000006 0000000000006c6c 0000000000000000
[   83.844589]  000000000000006c 0000000000000096 ffffffff819ce2bc ffffffffffffff10
[   83.844592]  ffffffff81088679 0000000000000010 0000000000000246 ffff880c4b9ddcd8
[   83.844594] Call Trace:
[   83.844596]  [<ffffffff81088679>] ? vprintk_emit+0x1c9/0x4c0
[   83.844601]  [<ffffffff815ad449>] ? schedule+0x29/0x70
[   83.844606]  [<ffffffff81537bd2>] ? tcp_splice_data_recv+0x42/0x50
[   83.844610]  [<ffffffff8153beaa>] ? tcp_read_sock+0xda/0x260
[   83.844613]  [<ffffffff81537b90>] ? tcp_prequeue_process+0xb0/0xb0
[   83.844615]  [<ffffffff8153c0f0>] ? tcp_splice_read+0xc0/0x250
[   83.844618]  [<ffffffff814dc0c2>] ? sock_splice_read+0x22/0x30
[   83.844622]  [<ffffffff811b820b>] ? do_splice_to+0x7b/0xa0
[   83.844627]  [<ffffffff811ba4bc>] ? sys_splice+0x59c/0x5d0
[   83.844630]  [<ffffffff8119745b>] ? putname+0x2b/0x40
[   83.844633]  [<ffffffff8118bcb4>] ? do_sys_open+0x174/0x1e0
[   83.844636]  [<ffffffff815b6202>] ? system_call_fastpath+0x16/0x1b

if recv_actor() returns 0, we should stop immediately,
because looping wont give a chance to drain the pipe.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Willy Tarreau <w@1wt.eu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A regression is introduced by the following commit:

	commit 4d52cfbe
	Author: Eric Dumazet <eric.dumazet@gmail.com>
	Date:   Tue Jun 2 00:42:16 2009 -0700

	    net: ipv4/ip_sockglue.c cleanups

	    Pure cleanups

but it is not a pure cleanup...

	-               if (val != -1 && (val < 1 || val>255))
	+               if (val != -1 && (val < 0 || val > 255))

Since there is no reason provided to allow ttl=0, change it back.
Reported-by: Nnitin padalia <padalia.nitin@gmail.com>
Cc: nitin padalia <padalia.nitin@gmail.com>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

IPsec tunnel does not set ECN field to CE in inner header when
the ECN field in the outer header is CE, and the ECN field in
the inner header is ECT(0) or ECT(1).

The cause is ipip_hdr() does not return the correct address of
inner header since skb->transport-header is not the inner header
after esp_input_done2(), or ah_input().
Signed-off-by: NLi RongQing <roy.qing.li@gmail.com>
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>

The NULL pointer check `!ifa' should come before its first use.

[ Bug origin : commit fd23c3b3
  (ipv4: Add hash table of interface addresses) in linux-2.6.39 ]
Signed-off-by: NXi Wang <xi.wang@gmail.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Up to now, the debug and info messages from the ipconfig subsytem
claim to display the IP address of the DHCP/BOOTP server but
display instead the IP address of the bootserver.  Fix that.
Signed-off-by: NPhilippe De Muyter <phdm@macqel.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ipgre_tunnel_xmit() incorrectly sets transport header to inner payload
instead of GRE header. It seems copy-and-pasted from ipip.c.
So set transport header to gre header.
(In ipip case the transport header is the inner ip header, so that's
correct.)

Found by inspection. In practice the incorrect transport header
doesn't matter because the skb usually is sent to another net_device
or socket, so the transport header isn't referenced.
Signed-off-by: NIsaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit 96e0bf4b (tcp: Discard segments that ack data not yet
sent) John Dykstra enforced a check against ack sequences.

In commit 354e4aa3 (tcp: RFC 5961 5.2 Blind Data Injection Attack
Mitigation) I added more safety tests.

But we missed fact that these tests are not performed if ACK bit is
not set.

RFC 793 3.9 mandates TCP should drop a frame without ACK flag set.

" fifth check the ACK field,
      if the ACK bit is off drop the segment and return"

Not doing so permits an attacker to only guess an acceptable sequence
number, evading stronger checks.

Many thanks to Zhiyun Qian for bringing this issue to our attention.

See :
http://web.eecs.umich.edu/~zhiyunq/pub/ccs12_TCP_sequence_number_inference.pdfReported-by: NZhiyun Qian <zhiyunq@umich.edu>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Nandita Dukkipati <nanditad@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: John Dykstra <john.dykstra1@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Sedat reported the following commit caused a regression:

commit 9650388b
Author: Eric Dumazet <edumazet@google.com>
Date:   Fri Dec 21 07:32:10 2012 +0000

    ipv4: arp: fix a lockdep splat in arp_solicit

This is due to the 6th parameter of arp_send() needs to be NULL
for the broadcast case, the above commit changed it to an all-zero
array by mistake.
Reported-by: NSedat Dilek <sedat.dilek@gmail.com>
Tested-by: NSedat Dilek <sedat.dilek@gmail.com>
Cc: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Julian Anastasov <ja@ssi.bg>
Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Yan Burman reported following lockdep warning :

=============================================
[ INFO: possible recursive locking detected ]
3.7.0+ #24 Not tainted
---------------------------------------------
swapper/1/0 is trying to acquire lock:
  (&n->lock){++--..}, at: [<ffffffff8139f56e>] __neigh_event_send
+0x2e/0x2f0

but task is already holding lock:
  (&n->lock){++--..}, at: [<ffffffff813f63f4>] arp_solicit+0x1d4/0x280

other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&n->lock);
   lock(&n->lock);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

4 locks held by swapper/1/0:
  #0:  (((&n->timer))){+.-...}, at: [<ffffffff8104b350>]
call_timer_fn+0x0/0x1c0
  #1:  (&n->lock){++--..}, at: [<ffffffff813f63f4>] arp_solicit
+0x1d4/0x280
  #2:  (rcu_read_lock_bh){.+....}, at: [<ffffffff81395400>]
dev_queue_xmit+0x0/0x5d0
  #3:  (rcu_read_lock_bh){.+....}, at: [<ffffffff813cb41e>]
ip_finish_output+0x13e/0x640

stack backtrace:
Pid: 0, comm: swapper/1 Not tainted 3.7.0+ #24
Call Trace:
  <IRQ>  [<ffffffff8108c7ac>] validate_chain+0xdcc/0x11f0
  [<ffffffff8108d570>] ? __lock_acquire+0x440/0xc30
  [<ffffffff81120565>] ? kmem_cache_free+0xe5/0x1c0
  [<ffffffff8108d570>] __lock_acquire+0x440/0xc30
  [<ffffffff813c3570>] ? inet_getpeer+0x40/0x600
  [<ffffffff8108d570>] ? __lock_acquire+0x440/0xc30
  [<ffffffff8139f56e>] ? __neigh_event_send+0x2e/0x2f0
  [<ffffffff8108ddf5>] lock_acquire+0x95/0x140
  [<ffffffff8139f56e>] ? __neigh_event_send+0x2e/0x2f0
  [<ffffffff8108d570>] ? __lock_acquire+0x440/0xc30
  [<ffffffff81448d4b>] _raw_write_lock_bh+0x3b/0x50
  [<ffffffff8139f56e>] ? __neigh_event_send+0x2e/0x2f0
  [<ffffffff8139f56e>] __neigh_event_send+0x2e/0x2f0
  [<ffffffff8139f99b>] neigh_resolve_output+0x16b/0x270
  [<ffffffff813cb62d>] ip_finish_output+0x34d/0x640
  [<ffffffff813cb41e>] ? ip_finish_output+0x13e/0x640
  [<ffffffffa046f146>] ? vxlan_xmit+0x556/0xbec [vxlan]
  [<ffffffff813cb9a0>] ip_output+0x80/0xf0
  [<ffffffff813ca368>] ip_local_out+0x28/0x80
  [<ffffffffa046f25a>] vxlan_xmit+0x66a/0xbec [vxlan]
  [<ffffffffa046f146>] ? vxlan_xmit+0x556/0xbec [vxlan]
  [<ffffffff81394a50>] ? skb_gso_segment+0x2b0/0x2b0
  [<ffffffff81449355>] ? _raw_spin_unlock_irqrestore+0x65/0x80
  [<ffffffff81394c57>] ? dev_queue_xmit_nit+0x207/0x270
  [<ffffffff813950c8>] dev_hard_start_xmit+0x298/0x5d0
  [<ffffffff813956f3>] dev_queue_xmit+0x2f3/0x5d0
  [<ffffffff81395400>] ? dev_hard_start_xmit+0x5d0/0x5d0
  [<ffffffff813f5788>] arp_xmit+0x58/0x60
  [<ffffffff813f59db>] arp_send+0x3b/0x40
  [<ffffffff813f6424>] arp_solicit+0x204/0x280
  [<ffffffff813a1a70>] ? neigh_add+0x310/0x310
  [<ffffffff8139f515>] neigh_probe+0x45/0x70
  [<ffffffff813a1c10>] neigh_timer_handler+0x1a0/0x2a0
  [<ffffffff8104b3cf>] call_timer_fn+0x7f/0x1c0
  [<ffffffff8104b350>] ? detach_if_pending+0x120/0x120
  [<ffffffff8104b748>] run_timer_softirq+0x238/0x2b0
  [<ffffffff813a1a70>] ? neigh_add+0x310/0x310
  [<ffffffff81043e51>] __do_softirq+0x101/0x280
  [<ffffffff814518cc>] call_softirq+0x1c/0x30
  [<ffffffff81003b65>] do_softirq+0x85/0xc0
  [<ffffffff81043a7e>] irq_exit+0x9e/0xc0
  [<ffffffff810264f8>] smp_apic_timer_interrupt+0x68/0xa0
  [<ffffffff8145122f>] apic_timer_interrupt+0x6f/0x80
  <EOI>  [<ffffffff8100a054>] ? mwait_idle+0xa4/0x1c0
  [<ffffffff8100a04b>] ? mwait_idle+0x9b/0x1c0
  [<ffffffff8100a6a9>] cpu_idle+0x89/0xe0
  [<ffffffff81441127>] start_secondary+0x1b2/0x1b6

Bug is from arp_solicit(), releasing the neigh lock after arp_send()
In case of vxlan, we eventually need to write lock a neigh lock later.

Its a false positive, but we can get rid of it without lockdep
annotations.

We can instead use neigh_ha_snapshot() helper.
Reported-by: NYan Burman <yanb@mellanox.com>
Signed-off-by: NEric Dumazet <edumazet@google.com>
Acked-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Once skb_realloc_headroom() is called, tiph might point to freed memory.

Cache tiph->ttl value before the reallocation, to avoid unexpected
behavior.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Isaku Yamahata <yamahata@valinux.co.jp>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ipgre_tunnel_xmit() parses network header as IP unconditionally.
But transmitting packets are not always IP packet. For example such packet
can be sent by packet socket with sockaddr_ll.sll_protocol set.
So make the function check if skb->protocol is IP.
Signed-off-by: NIsaku Yamahata <yamahata@valinux.co.jp>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since (a0ecb85a netfilter: nf_nat: Handle routing changes in MASQUERADE
target), the MASQUERADE target handles routing changes which affect
the output interface of a connection, but only for ESTABLISHED
connections.  It is also possible for NEW connections which
already have a conntrack entry to be affected by routing changes.

This adds a check to drop entries in the NEW+conntrack state
when the oif has changed.
Signed-off-by: NAndrew Collins <bsderandrew@gmail.com>
Acked-by: NJozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

The problem occurs when iptables constructs the tcp reset packet.
It doesn't initialize the pointer to the tcp header within the skb.
When the skb is passed to the ixgbe driver for transmit, the ixgbe
driver attempts to access the tcp header and crashes.
Currently, other drivers (such as our 1G e1000e or igb drivers) don't
access the tcp header on transmit unless the TSO option is turned on.

<1>BUG: unable to handle kernel NULL pointer dereference at 0000000d
<1>IP: [<d081621c>] ixgbe_xmit_frame_ring+0x8cc/0x2260 [ixgbe]
<4>*pdpt = 0000000085e5d001 *pde = 0000000000000000
<0>Oops: 0000 [#1] SMP
[...]
<4>Pid: 0, comm: swapper Tainted: P            2.6.35.12 #1 Greencity/Thurley
<4>EIP: 0060:[<d081621c>] EFLAGS: 00010246 CPU: 16
<4>EIP is at ixgbe_xmit_frame_ring+0x8cc/0x2260 [ixgbe]
<4>EAX: c7628820 EBX: 00000007 ECX: 00000000 EDX: 00000000
<4>ESI: 00000008 EDI: c6882180 EBP: dfc6b000 ESP: ced95c48
<4> DS: 007b ES: 007b FS: 00d8 GS: 0000 SS: 0068
<0>Process swapper (pid: 0, ti=ced94000 task=ced73bd0 task.ti=ced94000)
<0>Stack:
<4> cbec7418 c779e0d8 c77cc888 c77cc8a8 0903010a 00000000 c77c0008 00000002
<4><0> cd4997c0 00000010 dfc6b000 00000000 d0d176c9 c77cc8d8 c6882180 cbec7318
<4><0> 00000004 00000004 cbec7230 cbec7110 00000000 cbec70c0 c779e000 00000002
<0>Call Trace:
<4> [<d0d176c9>] ? 0xd0d176c9
<4> [<d0d18a4d>] ? 0xd0d18a4d
<4> [<411e243e>] ? dev_hard_start_xmit+0x218/0x2d7
<4> [<411f03d7>] ? sch_direct_xmit+0x4b/0x114
<4> [<411f056a>] ? __qdisc_run+0xca/0xe0
<4> [<411e28b0>] ? dev_queue_xmit+0x2d1/0x3d0
<4> [<411e8120>] ? neigh_resolve_output+0x1c5/0x20f
<4> [<411e94a1>] ? neigh_update+0x29c/0x330
<4> [<4121cf29>] ? arp_process+0x49c/0x4cd
<4> [<411f80c9>] ? nf_hook_slow+0x3f/0xac
<4> [<4121ca8d>] ? arp_process+0x0/0x4cd
<4> [<4121ca8d>] ? arp_process+0x0/0x4cd
<4> [<4121c6d5>] ? T.901+0x38/0x3b
<4> [<4121c918>] ? arp_rcv+0xa3/0xb4
<4> [<4121ca8d>] ? arp_process+0x0/0x4cd
<4> [<411e1173>] ? __netif_receive_skb+0x32b/0x346
<4> [<411e19e1>] ? netif_receive_skb+0x5a/0x5f
<4> [<411e1ea9>] ? napi_skb_finish+0x1b/0x30
<4> [<d0816eb4>] ? ixgbe_xmit_frame_ring+0x1564/0x2260 [ixgbe]
<4> [<41013468>] ? lapic_next_event+0x13/0x16
<4> [<410429b2>] ? clockevents_program_event+0xd2/0xe4
<4> [<411e1b03>] ? net_rx_action+0x55/0x127
<4> [<4102da1a>] ? __do_softirq+0x77/0xeb
<4> [<4102dab1>] ? do_softirq+0x23/0x27
<4> [<41003a67>] ? do_IRQ+0x7d/0x8e
<4> [<41002a69>] ? common_interrupt+0x29/0x30
<4> [<41007bcf>] ? mwait_idle+0x48/0x4d
<4> [<4100193b>] ? cpu_idle+0x37/0x4c
<0>Code: df 09 d7 0f 94 c2 0f b6 d2 e9 e7 fb ff ff 31 db 31 c0 e9 38
ff ff ff 80 78 06 06 0f 85 3e fb ff ff 8b 7c 24 38 8b 8f b8 00 00 00
<0f> b6 51 0d f6 c2 01 0f 85 27 fb ff ff 80 e2 02 75 0d 8b 6c 24
<0>EIP: [<d081621c>] ixgbe_xmit_frame_ring+0x8cc/0x2260 [ixgbe] SS:ESP
Signed-off-by: NMukund Jampala <jbmukund@gmail.com>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>

If in either of the above functions inet_csk_route_child_sock() or
__inet_inherit_port() fails, the newsk will not be freed:

unreferenced object 0xffff88022e8a92c0 (size 1592):
  comm "softirq", pid 0, jiffies 4294946244 (age 726.160s)
  hex dump (first 32 bytes):
    0a 01 01 01 0a 01 01 02 00 00 00 00 a7 cc 16 00  ................
    02 00 03 01 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff8153d190>] kmemleak_alloc+0x21/0x3e
    [<ffffffff810ab3e7>] kmem_cache_alloc+0xb5/0xc5
    [<ffffffff8149b65b>] sk_prot_alloc.isra.53+0x2b/0xcd
    [<ffffffff8149b784>] sk_clone_lock+0x16/0x21e
    [<ffffffff814d711a>] inet_csk_clone_lock+0x10/0x7b
    [<ffffffff814ebbc3>] tcp_create_openreq_child+0x21/0x481
    [<ffffffff814e8fa5>] tcp_v4_syn_recv_sock+0x3a/0x23b
    [<ffffffff814ec5ba>] tcp_check_req+0x29f/0x416
    [<ffffffff814e8e10>] tcp_v4_do_rcv+0x161/0x2bc
    [<ffffffff814eb917>] tcp_v4_rcv+0x6c9/0x701
    [<ffffffff814cea9f>] ip_local_deliver_finish+0x70/0xc4
    [<ffffffff814cec20>] ip_local_deliver+0x4e/0x7f
    [<ffffffff814ce9f8>] ip_rcv_finish+0x1fc/0x233
    [<ffffffff814cee68>] ip_rcv+0x217/0x267
    [<ffffffff814a7bbe>] __netif_receive_skb+0x49e/0x553
    [<ffffffff814a7cc3>] netif_receive_skb+0x50/0x82

This happens, because sk_clone_lock initializes sk_refcnt to 2, and thus
a single sock_put() is not enough to free the memory. Additionally, things
like xfrm, memcg, cookie_values,... may have been initialized.
We have to free them properly.

This is fixed by forcing a call to tcp_done(), ending up in
inet_csk_destroy_sock, doing the final sock_put(). tcp_done() is necessary,
because it ends up doing all the cleanup on xfrm, memcg, cookie_values,
xfrm,...

Before calling tcp_done, we have to set the socket to SOCK_DEAD, to
force it entering inet_csk_destroy_sock. To avoid the warning in
inet_csk_destroy_sock, inet_num has to be set to 0.
As inet_csk_destroy_sock does a dec on orphan_count, we first have to
increase it.

Calling tcp_done() allows us to remove the calls to
tcp_clear_xmit_timer() and tcp_cleanup_congestion_control().

A similar approach is taken for dccp by calling dccp_done().

This is in the kernel since 093d2823 (tproxy: fix hash locking issue
when using port redirection in __inet_inherit_port()), thus since
version >= 2.6.37.
Signed-off-by: NChristoph Paasch <christoph.paasch@uclouvain.be>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch replace the obsolete simple_strto<foo> with kstrto<foo>
Signed-off-by: NAbhijit Pawar <abhi.c.pawar@gmail.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ip_check_defrag() might be called from af_packet within the
RX path where shared SKBs are used, so it must not modify
the input SKB before it has unshared it for defragmentation.
Use skb_copy_bits() to get the IP header and only pull in
everything later.

The same is true for the other caller in macvlan as it is
called from dev->rx_handler which can also get a shared SKB.
Reported-by: NEric Leblond <eric@regit.org>
Cc: stable@vger.kernel.org
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add logic to verify that a port comparison byte code operation
actually has the second inet_diag_bc_op from which we read the port
for such operations.

Previously the code blindly referenced op[1] without first checking
whether a second inet_diag_bc_op struct could fit there. So a
malicious user could make the kernel read 4 bytes beyond the end of
the bytecode array by claiming to have a whole port comparison byte
code (2 inet_diag_bc_op structs) when in fact the bytecode was not
long enough to hold both.
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add logic to check the address family of the user-supplied conditional
and the address family of the connection entry. We now do not do
prefix matching of addresses from different address families (AF_INET
vs AF_INET6), except for the previously existing support for having an
IPv4 prefix match an IPv4-mapped IPv6 address (which this commit
maintains as-is).

This change is needed for two reasons:

(1) The addresses are different lengths, so comparing a 128-bit IPv6
prefix match condition to a 32-bit IPv4 connection address can cause
us to unwittingly walk off the end of the IPv4 address and read
garbage or oops.

(2) The IPv4 and IPv6 address spaces are semantically distinct, so a
simple bit-wise comparison of the prefixes is not meaningful, and
would lead to bogus results (except for the IPv4-mapped IPv6 case,
which this commit maintains).
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add logic to validate INET_DIAG_BC_S_COND and INET_DIAG_BC_D_COND
operations.

Previously we did not validate the inet_diag_hostcond, address family,
address length, and prefix length. So a malicious user could make the
kernel read beyond the end of the bytecode array by claiming to have a
whole inet_diag_hostcond when the bytecode was not long enough to
contain a whole inet_diag_hostcond of the given address family. Or
they could make the kernel read up to about 27 bytes beyond the end of
a connection address by passing a prefix length that exceeded the
length of addresses of the given family.
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix inet_diag to be aware of the fact that AF_INET6 TCP connections
instantiated for IPv4 traffic and in the SYN-RECV state were actually
created with inet_reqsk_alloc(), instead of inet6_reqsk_alloc(). This
means that for such connections inet6_rsk(req) returns a pointer to a
random spot in memory up to roughly 64KB beyond the end of the
request_sock.

With this bug, for a server using AF_INET6 TCP sockets and serving
IPv4 traffic, an inet_diag user like `ss state SYN-RECV` would lead to
inet_diag_fill_req() causing an oops or the export to user space of 16
bytes of kernel memory as a garbage IPv6 address, depending on where
the garbage inet6_rsk(req) pointed.
Signed-off-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This change allows the VXLAN to enable Tx checksum offloading even on
devices that do not support encapsulated checksum offloads. The
advantage to this is that it allows for the lower device to change due
to routing table changes without impacting features on the VXLAN itself.
Signed-off-by: NAlexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If SYN-ACK partially acks SYN-data, the client retransmits the
remaining data by tcp_retransmit_skb(). This increments lost recovery
state variables like tp->retrans_out in Open state. If loss recovery
happens before the retransmission is acked, it triggers the WARN_ON
check in tcp_fastretrans_alert(). For example: the client sends
SYN-data, gets SYN-ACK acking only ISN, retransmits data, sends
another 4 data packets and get 3 dupacks.

Since the retransmission is not caused by network drop it should not
update the recovery state variables. Further the server may return a
smaller MSS than the cached MSS used for SYN-data, so the retranmission
needs a loop. Otherwise some data will not be retransmitted until timeout
or other loss recovery events.
Signed-off-by: NYuchung Cheng <ycheng@google.com>
Acked-by: NNeal Cardwell <ncardwell@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit f1ce3062 (ipv4: Remove 'rt_dst' from 'struct rtable') removes the
call to ipmr_get_route(), which will get multicast parameters of the route.

I revert the part of the patch that remove this call. I think the goal was only
to get rid of rt_dst field.

The patch is only compiled-tested. My first idea was to remove ipmr_get_route()
because rt_fill_info() was the only user, but it seems the previous patch cleans
the code a bit too much ;-)
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch allows to monitor mfc activities via rtnetlink.
To avoid parsing two times the mfc oifs, we use maxvif to allocate the rtnl
msg, thus we may allocate some superfluous space.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

/proc/net/ip[6]_mr_cache allows to get all mfc entries, even if they are put in
the unresolved list (mfc[6]_unres_queue). But only the table RT_TABLE_DEFAULT is
displayed.
This patch adds the parsing of the unresolved list when the dump is made via
rtnetlink, hence each table can be checked.

In IPv6, we set rtm_type in ip6mr_fill_mroute(), because in case of unresolved
mfc __ip6mr_fill_mroute() will not set it. In IPv4, it is already done.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A mfc entry can be static or not (added via the mroute_sk socket). The patch
reports MFC_STATIC flag into rtm_protocol by setting rtm_protocol to
RTPROT_STATIC or RTPROT_MROUTED.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These statistics can be checked only via /proc/net/ip_mr_cache or
SIOCGETSGCNT[_IN6] and thus only for the table RT_TABLE_DEFAULT.
Advertising them via rtnetlink allows to get statistics for all cache entries,
whatever the table is.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch advertise the MC_FORWARDING status for IPv4 and IPv6.
This field is readonly, only multicast engine in the kernel updates it.
Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the route changes (backup default route, VPNs) which affect a
masqueraded target, the packets were sent out with the outdated source
address. The patch addresses the issue by comparing the outgoing interface
directly with the masqueraded interface in the nat table.

Events are inefficient in this case, because it'd require adding route
events to the network core and then scanning the whole conntrack table
and re-checking the route for all entry.
Signed-off-by: NJozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>