INADDR_ANY is hard-coded when activating UDP bearer. So, we could not
bind to a specific IP address even with replicast mode using - given
remote ip address instead of using multicast ip address.

In this commit, we fixed it by checking and switch to use appropriate
local ip address.

before:
$netstat -plu
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address
udp        0      0 **0.0.0.0:6118**            0.0.0.0:*

after:
$netstat -plu
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address
udp        0      0 **10.0.0.2:6118**           0.0.0.0:*
Acked-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NHoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, all bearers are configured with MTU value same as the
underlying L2 device. However, in case of bearers with media type
UDP, higher throughput is possible with a fixed and higher emulated
MTU value than adapting to the underlying L2 MTU.

In this commit, we introduce a parameter mtu in struct tipc_media
and a default value is set for UDP. A default value of 14k
was determined by experimentation and found to have a higher throughput
than 16k. MTU for UDP bearers are assigned the above set value of
media MTU.
Acked-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NGhantaKrishnamurthy MohanKrishna <mohan.krishna.ghanta.krishnamurthy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Release alloced resource before return from the error handling
case in tipc_udp_enable(), otherwise will cause memory leak.

Fixes: 52dfae5c ("tipc: obtain node identity from interface by default")
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Selecting and explicitly configuring a TIPC node identity may be
unwanted in some cases.

In this commit we introduce a default setting if the identity has not
been set at the moment the first bearer is enabled. We do this by
using a raw copy of a unique identifier from the used interface: MAC
address in the case of an L2 bearer, IPv4/IPv6 address in the case
of a UDP bearer.
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove the second tipc_rcv() call in tipc_udp_recv(). We have just
checked that the bearer is not up, and calling tipc_rcv() with a bearer
that is not up leads to a TIPC div-by-zero crash in
tipc_node_calculate_timer(). The crash is rare in practice, but can
happen like this:

  We're enabling a bearer, but it's not yet up and fully initialized.
  At the same time we receive a discovery packet, and in tipc_udp_recv()
  we end up calling tipc_rcv() with the not-yet-initialized bearer,
  causing later the div-by-zero crash in tipc_node_calculate_timer().

Jon Maloy explains the impact of removing the second tipc_rcv() call:
  "link setup in the worst case will be delayed until the next arriving
   discovery messages, 1 sec later, and this is an acceptable delay."

As the tipc_rcv() call is removed, just leave the function via the
rcu_out label, so that we will kfree_skb().

[   12.590450] Own node address <1.1.1>, network identity 1
[   12.668088] divide error: 0000 [#1] SMP
[   12.676952] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.14.2-dirty #1
[   12.679225] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014
[   12.682095] task: ffff8c2a761edb80 task.stack: ffffa41cc0cac000
[   12.684087] RIP: 0010:tipc_node_calculate_timer.isra.12+0x45/0x60 [tipc]
[   12.686486] RSP: 0018:ffff8c2a7fc838a0 EFLAGS: 00010246
[   12.688451] RAX: 0000000000000000 RBX: ffff8c2a5b382600 RCX: 0000000000000000
[   12.691197] RDX: 0000000000000000 RSI: ffff8c2a5b382600 RDI: ffff8c2a5b382600
[   12.693945] RBP: ffff8c2a7fc838b0 R08: 0000000000000001 R09: 0000000000000001
[   12.696632] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8c2a5d8949d8
[   12.699491] R13: ffffffff95ede400 R14: 0000000000000000 R15: ffff8c2a5d894800
[   12.702338] FS:  0000000000000000(0000) GS:ffff8c2a7fc80000(0000) knlGS:0000000000000000
[   12.705099] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   12.706776] CR2: 0000000001bb9440 CR3: 00000000bd009001 CR4: 00000000003606e0
[   12.708847] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   12.711016] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   12.712627] Call Trace:
[   12.713390]  <IRQ>
[   12.714011]  tipc_node_check_dest+0x2e8/0x350 [tipc]
[   12.715286]  tipc_disc_rcv+0x14d/0x1d0 [tipc]
[   12.716370]  tipc_rcv+0x8b0/0xd40 [tipc]
[   12.717396]  ? minmax_running_min+0x2f/0x60
[   12.718248]  ? dst_alloc+0x4c/0xa0
[   12.718964]  ? tcp_ack+0xaf1/0x10b0
[   12.719658]  ? tipc_udp_is_known_peer+0xa0/0xa0 [tipc]
[   12.720634]  tipc_udp_recv+0x71/0x1d0 [tipc]
[   12.721459]  ? dst_alloc+0x4c/0xa0
[   12.722130]  udp_queue_rcv_skb+0x264/0x490
[   12.722924]  __udp4_lib_rcv+0x21e/0x990
[   12.723670]  ? ip_route_input_rcu+0x2dd/0xbf0
[   12.724442]  ? tcp_v4_rcv+0x958/0xa40
[   12.725039]  udp_rcv+0x1a/0x20
[   12.725587]  ip_local_deliver_finish+0x97/0x1d0
[   12.726323]  ip_local_deliver+0xaf/0xc0
[   12.726959]  ? ip_route_input_noref+0x19/0x20
[   12.727689]  ip_rcv_finish+0xdd/0x3b0
[   12.728307]  ip_rcv+0x2ac/0x360
[   12.728839]  __netif_receive_skb_core+0x6fb/0xa90
[   12.729580]  ? udp4_gro_receive+0x1a7/0x2c0
[   12.730274]  __netif_receive_skb+0x1d/0x60
[   12.730953]  ? __netif_receive_skb+0x1d/0x60
[   12.731637]  netif_receive_skb_internal+0x37/0xd0
[   12.732371]  napi_gro_receive+0xc7/0xf0
[   12.732920]  receive_buf+0x3c3/0xd40
[   12.733441]  virtnet_poll+0xb1/0x250
[   12.733944]  net_rx_action+0x23e/0x370
[   12.734476]  __do_softirq+0xc5/0x2f8
[   12.734922]  irq_exit+0xfa/0x100
[   12.735315]  do_IRQ+0x4f/0xd0
[   12.735680]  common_interrupt+0xa2/0xa2
[   12.736126]  </IRQ>
[   12.736416] RIP: 0010:native_safe_halt+0x6/0x10
[   12.736925] RSP: 0018:ffffa41cc0cafe90 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff4d
[   12.737756] RAX: 0000000000000000 RBX: ffff8c2a761edb80 RCX: 0000000000000000
[   12.738504] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[   12.739258] RBP: ffffa41cc0cafe90 R08: 0000014b5b9795e5 R09: ffffa41cc12c7e88
[   12.740118] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002
[   12.740964] R13: ffff8c2a761edb80 R14: 0000000000000000 R15: 0000000000000000
[   12.741831]  default_idle+0x2a/0x100
[   12.742323]  arch_cpu_idle+0xf/0x20
[   12.742796]  default_idle_call+0x28/0x40
[   12.743312]  do_idle+0x179/0x1f0
[   12.743761]  cpu_startup_entry+0x1d/0x20
[   12.744291]  start_secondary+0x112/0x120
[   12.744816]  secondary_startup_64+0xa5/0xa5
[   12.745367] Code: b9 f4 01 00 00 48 89 c2 48 c1 ea 02 48 3d d3 07 00
00 48 0f 47 d1 49 8b 0c 24 48 39 d1 76 07 49 89 14 24 48 89 d1 31 d2 48
89 df <48> f7 f1 89 c6 e8 81 6e ff ff 5b 41 5c 5d c3 66 90 66 2e 0f 1f
[   12.747527] RIP: tipc_node_calculate_timer.isra.12+0x45/0x60 [tipc] RSP: ffff8c2a7fc838a0
[   12.748555] ---[ end trace 1399ab83390650fd ]---
[   12.749296] Kernel panic - not syncing: Fatal exception in interrupt
[   12.750123] Kernel Offset: 0x13200000 from 0xffffffff82000000
(relocation range: 0xffffffff80000000-0xffffffffbfffffff)
[   12.751215] Rebooting in 60 seconds..

Fixes: c9b64d49 ("tipc: add replicast peer discovery")
Signed-off-by: NTommi Rantala <tommi.t.rantala@nokia.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Pass the new extended ACK reporting struct to all of the generic
netlink parsing functions. For now, pass NULL in almost all callers
(except for some in the core.)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

As a preparation for the 'replicast' functionality we are going to
introduce in the next commits, we need the broadcast base structure to
store whether bearer broadcast is available at all from the currently
used bearer or bearers.

We do this by adding a new function tipc_bearer_bcast_support() to
the bearer layer, and letting the bearer selection function in
bcast.c use this to give a new boolean field, 'bcast_support' the
appropriate value.
Reviewed-by: NParthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Qian Zhang (张谦) reported a potential socket buffer overflow in
tipc_msg_build() which is also known as CVE-2016-8632: due to
insufficient checks, a buffer overflow can occur if MTU is too short for
even tipc headers. As anyone can set device MTU in a user/net namespace,
this issue can be abused by a regular user.

As agreed in the discussion on Ben Hutchings' original patch, we should
check the MTU at the moment a bearer is attached rather than for each
processed packet. We also need to repeat the check when bearer MTU is
adjusted to new device MTU. UDP case also needs a check to avoid
overflow when calculating bearer MTU.

Fixes: b97bf3fd ("[TIPC] Initial merge")
Signed-off-by: NMichal Kubecek <mkubecek@suse.cz>
Reported-by: NQian Zhang (张谦) <zhangqian-c@360.cn>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We should clear out the padding and unused struct members so that we
don't expose stack information to userspace.

Fixes: fdb3accc ('tipc: add the ability to get UDP options via netlink')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

'ub' is malloced in tipc_udp_enable() and should be freed before
leaving from the error handling cases, otherwise it will cause
memory leak.

Fixes: ba5aa84a ("tipc: split UDP nl address parsing")
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When using replicast a UDP bearer can have an arbitrary amount of
remote ip addresses associated with it. This means we cannot simply
add all remote ip addresses to an existing bearer data message as it
might fill the message, leaving us with a truncated message that we
can't safely resume. To handle this we introduce the new netlink
command TIPC_NL_UDP_GET_REMOTEIP. This command is intended to be
called when the bearer data message has the
TIPC_NLA_UDP_MULTI_REMOTEIP flag set, indicating there are more than
one remote ip (replicast).
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Reviewed-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add UDP bearer options to netlink bearer get message. This is used by
the tipc user space tool to display UDP options.

The UDP bearer information is passed using either a sockaddr_in or
sockaddr_in6 structs. This means the user space receiver should
intermediately store the retrieved data in a large enough struct
(sockaddr_strage) before casting to the proper IP version type.
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Reviewed-by: NJon Maloy <jon.maloy@ericsson.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Automatically learn UDP remote IP addresses of communicating peers by
looking at the source IP address of incoming TIPC link configuration
messages (neighbor discovery).

This makes configuration slightly easier and removes the problematic
scenario where a node receives directly addressed neighbor discovery
messages sent using replicast which the node cannot "reply" to using
mutlicast, leaving the link FSM in a limbo state.
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Reviewed-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch introduces UDP replicast. A concept where we emulate
multicast by sending multiple unicast messages to configured peers.

The purpose of replicast is mainly to be able to use TIPC in cloud
environments where IP multicast is disabled. Using replicas to unicast
multicast messages is costly as we have to copy each skb and send the
copies individually.
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Reviewed-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add a function to check if a tipc UDP media address is a multicast
address or not. This is a purely cosmetic change.
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Reviewed-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Split the UDP send function into two. One callback that prepares the
skb and one transmit function that sends the skb. This will come in
handy in later patches, when we introduce UDP replicast.
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Reviewed-by: NJon Maloy <jon.maloy@ericsson.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Split the UDP netlink parse function so that it only parses one
netlink attribute at the time. This makes the parse function more
generic and allow future UDP API functions to use it for parsing.
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Reviewed-by: NJon Maloy <jon.maloy@ericsson.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix to return a negative error code in enable_mcast() error handling
case, and release udp socket when necessary.

Fixes: d0f91938 ("tipc: add ip/udp media type")
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit 5b7066c3 ("tipc: stricter filtering of packets in bearer
layer") we introduced a method of filtering out messages while a bearer
is being reset, to avoid that links may be re-created and come back in
working state while we are still in the process of shutting them down.

This solution works well, but is limited to only work with L2 media, which
is insufficient with the increasing use of UDP as carrier media.

We now replace this solution with a more generic one, by introducing a
new flag "up" in the generic struct tipc_bearer. This field will be set
and reset at the same locations as with the previous solution, while
the packet filtering is moved to the generic code for the sending side.
On the receiving side, the filtering is still done in media specific
code, but now including the UDP bearer.
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Context implies that port in struct "udp_media_addr" is referring
to a UDP port.
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Expand headroom further in order to be able to fit the larger IPv6
header. Prior to this patch this caused a skb under panic for certain
tipc packets when using IPv6 UDP bearer(s).
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch extends udp_tunnel6_xmit_skb() to pass in the IPv6 flow label
from call sites. Currently, there's no such option and it's always set to
zero when writing ip6_flow_hdr(). Add a label member to ip_tunnel_key, so
that flow-based tunnels via collect metadata frontends can make use of it.
vxlan and geneve will be converted to add flow label support separately.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make the c files less cluttered and enable netlink attributes to be
shared between files.
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Reviewed-by: NJon Maloy <jon.maloy@ericsson.com>
Acked-by: NParthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make sure the user has provided a scope for multicast and link local
addresses used locally by a UDP bearer.
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The netlink policy for TIPC_NLA_UDP_LOCAL and TIPC_NLA_UDP_REMOTE
is of type binary with a defined length. This causes the policy
framework to threat the defined length as maximum length.

There is however no protection against a user sending a smaller
amount of data. Prior to this patch this wasn't handled which could
result in a partially incomplete sockaddr_storage struct containing
uninitialized data.

In this patch we use nla_memcpy() when copying the user data. This
ensures a potential gap at the end is cleared out properly.

This was found by Julia with Coccinelle tool.
Reported-by: NDaniel Borkmann <daniel@iogearbox.net>
Reported-by: NJulia Lawall <julia.lawall@lip6.fr>
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Prior to this patch enabling a IPv4 UDP bearer caused a null pointer
dereference in iptunnel_xmit_stats(), when it tried to dereference the
net device from the skb. To resolve this we now point the skb device
to the net device resolved from the routing table.

Fixes: 039f5062 (ip_tunnel: Move stats update to iptunnel_xmit())
Signed-off-by: NRichard Alpe <richard.alpe@ericsson.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NErik Hugne <erik.hugne@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

By moving stats update into iptunnel_xmit(), we can simplify
iptunnel_xmit() usage. With this change there is no need to
call another function (iptunnel_xmit_stats()) to update stats
in tunnel xmit code path.
Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Coverity says:

*** CID 1338065:  Error handling issues  (CHECKED_RETURN)
/net/tipc/udp_media.c: 162 in tipc_udp_send_msg()
156     	struct udp_media_addr *dst = (struct udp_media_addr *)&dest->value;
157     	struct udp_media_addr *src = (struct udp_media_addr *)&b->addr.value;
158     	struct sk_buff *clone;
159     	struct rtable *rt;
160
161     	if (skb_headroom(skb) < UDP_MIN_HEADROOM)
>>>     CID 1338065:  Error handling issues  (CHECKED_RETURN)
>>>     Calling "pskb_expand_head" without checking return value (as is done elsewhere 51 out of 56 times).
162     		pskb_expand_head(skb, UDP_MIN_HEADROOM, 0, GFP_ATOMIC);
163
164     	clone = skb_clone(skb, GFP_ATOMIC);
165     	skb_set_inner_protocol(clone, htons(ETH_P_TIPC));
166     	ub = rcu_dereference_rtnl(b->media_ptr);
167     	if (!ub) {

When expanding buffer headroom over udp tunnel with pskb_expand_head(),
it's unfortunate that we don't check its return value. As a result, if
the function returns an error code due to the lack of memory, it may
cause unpredictable consequence as we unconditionally consider that
it's always successful.

Fixes: e5356794 ("tipc: conditionally expand buffer headroom over udp tunnel")
Reported-by: <scan-admin@coverity.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit 5cbb28a4 ("tipc: linearize arriving NAME_DISTR
and LINK_PROTO buffers") we added linearization of NAME_DISTRIBUTOR,
LINK_PROTOCOL/RESET and LINK_PROTOCOL/ACTIVATE to the function
tipc_udp_recv(). The location of the change was selected in order
to make the commit easily appliable to 'net' and 'stable'.

We now move this linearization to where it should be done, in the
functions tipc_named_rcv() and tipc_link_proto_rcv() respectively.
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Testing of the new UDP bearer has revealed that reception of
NAME_DISTRIBUTOR, LINK_PROTOCOL/RESET and LINK_PROTOCOL/ACTIVATE
message buffers is not prepared for the case that those may be
non-linear.

We now linearize all such buffers before they are delivered up to the
generic reception layer.

In order for the commit to apply cleanly to 'net' and 'stable', we do
the change in the function tipc_udp_recv() for now. Later, we will post
a commit to 'net-next' moving the linearization to generic code, in
tipc_named_rcv() and tipc_link_proto_rcv().

Fixes: commit d0f91938 ("tipc: add ip/udp media type")
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since all packet transmitters (link, bcast, discovery) are now sending
consumable buffer clones to the bearer layer, we can remove the
redundant buffer cloning that is perfomed in the lower level functions
tipc_l2_send_msg() and tipc_udp_send_msg().
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit d999297c ("tipc: reduce locking scope during packet reception")
we altered the packet retransmission function. Since then, when
restransmitting packets, we create a clone of the original buffer
using __pskb_copy(skb, MIN_H_SIZE), where MIN_H_SIZE is the size of
the area we want to have copied, but also the smallest possible TIPC
packet size. The value of MIN_H_SIZE is 24.

Unfortunately, __pskb_copy() also has the effect that the headroom
of the cloned buffer takes the size MIN_H_SIZE. This is too small
for carrying the packet over the UDP tunnel bearer, which requires
a minimum headroom of 28 bytes. A change to just use pskb_copy()
lets the clone inherit the original headroom of 80 bytes, but also
assumes that the copied data area is of at least that size, something
that is not always the case. So that is not a viable solution.

We now fix this by adding a check for sufficient headroom in the
transmit function of udp_media.c, and expanding it when necessary.

Fixes: commit d999297c ("tipc: reduce locking scope during packet reception")
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a link is taken down because of a node local event, such as
disabling of a bearer or an interface, we currently leave it to the
peer node to discover the broken communication. The default time for
such failure discovery is 1.5-2 seconds.

If we instead allow the terminating link endpoint to send out a RESET
message at the moment it is reset, we can achieve the impression that
both endpoints are going down instantly. Since this is a very common
scenario, we find it worthwhile to make this small modification.

Apart from letting the link produce the said message, we also have to
ensure that the interface is able to transmit it before TIPC is
detached. We do this by performing the disabling of a bearer in three
steps:

1) Disable reception of TIPC packets from the interface in question.
2) Take down the links, while allowing them so send out a RESET message.
3) Disable transmission of TIPC packets on the interface.

Apart from this, we now have to react on the NETDEV_GOING_DOWN event,
instead of as currently the NEDEV_DOWN event, to ensure that such
transmission is possible during the teardown phase.
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch adds net argument to ipv6_stub_impl.ipv6_dst_lookup
for use cases where sk is not available (like mpls).
sk appears to be needed to get the namespace 'net' and is optional
otherwise. This patch series changes ipv6_stub_impl.ipv6_dst_lookup
to take net argument. sk remains optional.

All callers of ipv6_stub_impl.ipv6_dst_lookup have been modified
to pass net. I have modified them to use already available
'net' in the scope of the call. I can change them to
sock_net(sk) to avoid any unintended change in behaviour if sock
namespace is different. They dont seem to be from code inspection.
Signed-off-by: NRoopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

That was we can make sure the output path of ipv4/ipv6 operate on
the UDP socket rather than whatever random thing happens to be in
skb->sk.

Based upon a patch by Jiri Pirko.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>

When IPV6=m and TIPC=y, below error will appear during building kernel
image:

net/tipc/udp_media.c:196:
undefined reference to `ip6_dst_lookup'
make: *** [vmlinux] Error 1

As ip6_dst_lookup() is implemented in IPV6 and IPV6 is compiled as
module, ip6_dst_lookup() is not built-in core kernel image. As a
result, compiler cannot find 'ip6_dst_lookup' reference while
compiling TIPC code into core kernel image.

But with the method introduced by commit 5f81bd2e ("ipv6: export a
stub for IPv6 symbols used by vxlan"), we can avoid the compile error
through "ipv6_stub" pointer to access ip6_dst_lookup().

Fixes: d0f91938 ("tipc: add ip/udp media type")
Suggested-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We can't directly call ipv6_sock_mc_join() but should use the stub
instead and protect it around IS_ENABLED.

Fixes: d0f91938 ("tipc: add ip/udp media type")
Signed-off-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

in favor of their inner __ ones, which doesn't grab rtnl.

As these functions need to operate on a locked socket, we can't be
grabbing rtnl by then. It's too late and doing so causes reversed
locking.

So this patch:
- move rtnl handling to callers instead while already fixing some
  reversed locking situations, like on vxlan and ipvs code.
- renames __ ones to not have the __ mark:
  __ip_mc_{join,leave}_group -> ip_mc_{join,leave}_group
  __ipv6_sock_mc_{join,drop} -> ipv6_sock_mc_{join,drop}
Signed-off-by: NMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit d0f91938 ("tipc: add ip/udp media type") introduced
some new sparse warnings. Clean them up.
Signed-off-by: NErik Hugne <erik.hugne@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The ip/udp bearer can be configured in a point-to-point
mode by specifying both local and remote ip/hostname,
or it can be enabled in multicast mode, where links are
established to all tipc nodes that have joined the same
multicast group. The multicast IP address is generated
based on the TIPC network ID, but can be overridden by
using another multicast address as remote ip.
Signed-off-by: NErik Hugne <erik.hugne@ericsson.com>
Reviewed-by: NJon Maloy <jon.maloy@ericsson.com>
Reviewed-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>