Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most
netlink based interfaces (including recently added ones) are still not
setting it in kernel generated messages. Without the flag, message parsers
not aware of attribute semantics (e.g. wireshark dissector or libmnl's
mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display
the structure of their contents.

Unfortunately we cannot just add the flag everywhere as there may be
userspace applications which check nlattr::nla_type directly rather than
through a helper masking out the flags. Therefore the patch renames
nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start()
as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually
are rewritten to use nla_nest_start().

Except for changes in include/net/netlink.h, the patch was generated using
this semantic patch:

@@ expression E1, E2; @@
-nla_nest_start(E1, E2)
+nla_nest_start_noflag(E1, E2)

@@ expression E1, E2; @@
-nla_nest_start_noflag(E1, E2 | NLA_F_NESTED)
+nla_nest_start(E1, E2)
Signed-off-by: NMichal Kubecek <mkubecek@suse.cz>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

I forgot to remove one rcu_read_unlock() before a return statement.

Joy of mixing goto and return styles in a function :)

Fixes: 4109a2c3 ("tipc: tipc_udp_recv() cleanup vs rcu verbs")
Signed-off-by: NEric Dumazet <edumazet@google.com>
Reported-by: Nkbuild test robot <lkp@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

First thing tipc_udp_recv() does is to use rcu_dereference_sk_user_data(),
and this is really hinting we already own rcu_read_lock() from the caller
(UDP stack).

No need to add another rcu_read_lock()/rcu_read_unlock() pair.

Also use rcu_dereference() instead of rcu_dereference_rtnl()
in the data path.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Ying Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When using TIPC_SOCK_RECVQ_DEPTH for getsockopt(), it returns the
number of buffers in receive socket buffer which is not so helpful
for user space applications.

This commit introduces the new option TIPC_SOCK_RECVQ_USED which
returns the current allocated bytes of the receive socket buffer.
This helps user space applications dimension its buffer usage to
avoid buffer overload issue.
Signed-off-by: NTung Nguyen <tung.q.nguyen@dektech.com.au>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We find that sysctl_tipc_rmem and named_timeout do not have the right minimum
setting. sysctl_tipc_rmem should be larger than zero, like sysctl_tcp_rmem.
And named_timeout as a timeout setting should be not less than zero.

Fixes: cc79dd1b ("tipc: change socket buffer overflow control to respect sk_rcvbuf")
Fixes: a5325ae5 ("tipc: add name distributor resiliency queue")
Signed-off-by: NJie Liu <liujie165@huawei.com>
Reported-by: NQiang Ning <ningqiang1@huawei.com>
Reviewed-by: NZhiqiang Liu <liuzhiqiang26@huawei.com>
Reviewed-by: NMiaohe Lin <linmiaohe@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

According to the link FSM, when a link endpoint got RESET_MSG (- a
traditional one without the stopping bit) from its peer, it moves to
PEER_RESET state and raises a LINK_DOWN event which then resets the
link itself. Its state will become ESTABLISHING after the reset event
and the link will be re-established soon after this endpoint starts to
send ACTIVATE_MSG to the peer.

There is no problem with this mechanism, however the link resetting has
cleared the link 'in_session' flag (along with the other important link
data such as: the link 'mtu') that was correctly set up at the 1st step
(i.e. when this endpoint received the peer RESET_MSG). As a result, the
link will become ESTABLISHED, but the 'in_session' flag is not set, and
all STATE_MSG from its peer will be dropped at the link_validate_msg().
It means the link not synced and will sooner or later face a failure.

Since the link reset action is obviously needed for a new link session
(this is also true in the other situations), the problem here is that
the link is re-established a bit too early when the link endpoints are
not really in-sync yet. The commit forces a resync as already done in
the previous commit 91986ee1 ("tipc: fix link session and
re-establish issues") by simply varying the link 'peer_session' value
at the link_reset().
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In the function tipc_node_create() we protect the peer capability field
by using the node rw_lock. However, we access the lock directly instead
of using the dedicated functions for this, as we do everywhere else in
node.c. This cosmetic spot is fixed here.

Fixes: 40999f11 ("tipc: make link capability update thread safe")
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When binding multiple services with specific type 1Ki, 2Ki..,
this leads to some entries in the name table of publications
missing when listed out via 'tipc name show'.

The problem is at identify zero last_type conditional provided
via netlink. The first is initial 'type' when starting name table
dummping. The second is continuously with zero type (node state
service type). Then, lookup function failure to finding node state
service type in next iteration.

To solve this, adding more conditional to marked as dirty type and
lookup correct service type for the next iteration instead of select
the first service as initial 'type' zero.
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>

In commit 0ae955e2656d ("tipc: improve TIPC throughput by Gap ACK
blocks"), we enhance the link transmq by releasing as many packets as
possible with the multi-ACKs from peer node. This also means the queue
is now non-linear and the peer link deferdq becomes vital.

Whereas, in the case of link failover, all messages in the link transmq
need to be transmitted as tunnel messages in such a way that message
sequentiality and cardinality per sender is preserved. This requires us
to maintain the link deferdq somehow, so that when the tunnel messages
arrive, the inner user messages along with the ones in the deferdq will
be delivered to upper layer correctly.

The commit accomplishes this by defining a new queue in the TIPC link
structure to hold the old link deferdq when link failover happens and
process it upon receipt of tunnel messages.

Also, in the case of link syncing, the link deferdq will not be purged
to avoid unnecessary retransmissions that in the worst case will fail
because the packets might have been freed on the sending side.
Acked-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

For unicast transmission, the current NACK sending althorithm is over-
active that forces the sending side to retransmit a packet that is not
really lost but just arrived at the receiving side with some delay, or
even retransmit same packets that have already been retransmitted
before. As a result, many duplicates are observed also under normal
condition, ie. without packet loss.

One example case is: node1 transmits 1 2 3 4 10 5 6 7 8 9, when node2
receives packet #10, it puts into the deferdq. When the packet #5 comes
it sends NACK with gap [6 - 9]. However, shortly after that, when
packet #6 arrives, it pulls out packet #10 from the deferfq, but it is
still out of order, so it makes another NACK with gap [7 - 9] and so on
... Finally, node1 has to retransmit the packets 5 6 7 8 9 a number of
times, but in fact all the packets are not lost at all, so duplicates!

This commit reduces duplicates by changing the condition to send NACK,
also restricting the retransmissions on individual packets via a timer
of about 1ms. However, it also needs to say that too tricky condition
for NACKs or too long timeout value for retransmissions will result in
performance reducing! The criterias in this commit are found to be
effective for both the requirements to reduce duplicates but not affect
performance.

The tipc_link_rcv() is also improved to only dequeue skb from the link
deferdq if it is expected (ie. its seqno <= rcv_nxt).
Acked-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

During unicast link transmission, it's observed very often that because
of one or a few lost/dis-ordered packets, the sending side will fastly
reach the send window limit and must wait for the packets to be arrived
at the receiving side or in the worst case, a retransmission must be
done first. The sending side cannot release a lot of subsequent packets
in its transmq even though all of them might have already been received
by the receiving side.
That is, one or two packets dis-ordered/lost and dozens of packets have
to wait, this obviously reduces the overall throughput!

This commit introduces an algorithm to overcome this by using "Gap ACK
blocks". Basically, a Gap ACK block will consist of <ack, gap> numbers
that describes the link deferdq where packets have been got by the
receiving side but with gaps, for example:

      link deferdq: [1 2 3 4      10 11      13 14 15       20]
--> Gap ACK blocks:       <4, 5>,   <11, 1>,      <15, 4>, <20, 0>

The Gap ACK blocks will be sent to the sending side along with the
traditional ACK or NACK message. Immediately when receiving the message
the sending side will now not only release from its transmq the packets
ack-ed by the ACK but also by the Gap ACK blocks! So, more packets can
be enqueued and transmitted.
In addition, the sending side can now do "multi-retransmissions"
according to the Gaps reported in the Gap ACK blocks.

The new algorithm as verified helps greatly improve the TIPC throughput
especially under packet loss condition.

So far, a maximum of 32 blocks is quite enough without any "Too few Gap
ACK blocks" reports with a 5.0% packet loss rate, however this number
can be increased in the furture if needed.

Also, the patch is backward compatible.
Acked-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

skb somehow dequeued out of inputq before processing, it causes to
NULL pointer and kernel crashed.

Add checking skb valid before using.

Fixes: c55c8eda ("tipc: smooth change between replicast and broadcast")
Reported-by: NTuong Lien Tong <tuong.t.lien@dektech.com.au>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NHoang Le <hoang.h.le@dektech.com.au>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Syzbot found a crash:

  BUG: KMSAN: uninit-value in tipc_nl_compat_name_table_dump+0x54f/0xcd0 net/tipc/netlink_compat.c:872
  Call Trace:
    tipc_nl_compat_name_table_dump+0x54f/0xcd0 net/tipc/netlink_compat.c:872
    __tipc_nl_compat_dumpit+0x59e/0xda0 net/tipc/netlink_compat.c:215
    tipc_nl_compat_dumpit+0x63a/0x820 net/tipc/netlink_compat.c:280
    tipc_nl_compat_handle net/tipc/netlink_compat.c:1226 [inline]
    tipc_nl_compat_recv+0x1b5f/0x2750 net/tipc/netlink_compat.c:1265
    genl_family_rcv_msg net/netlink/genetlink.c:601 [inline]
    genl_rcv_msg+0x185f/0x1a60 net/netlink/genetlink.c:626
    netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2477
    genl_rcv+0x63/0x80 net/netlink/genetlink.c:637
    netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
    netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1336
    netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1917
    sock_sendmsg_nosec net/socket.c:622 [inline]
    sock_sendmsg net/socket.c:632 [inline]

  Uninit was created at:
    __alloc_skb+0x309/0xa20 net/core/skbuff.c:208
    alloc_skb include/linux/skbuff.h:1012 [inline]
    netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline]
    netlink_sendmsg+0xb82/0x1300 net/netlink/af_netlink.c:1892
    sock_sendmsg_nosec net/socket.c:622 [inline]
    sock_sendmsg net/socket.c:632 [inline]

It was supposed to be fixed on commit 974cb0e3 ("tipc: fix uninit-value
in tipc_nl_compat_name_table_dump") by checking TLV_GET_DATA_LEN(msg->req)
in cmd->header()/tipc_nl_compat_name_table_dump_header(), which is called
ahead of tipc_nl_compat_name_table_dump().

However, tipc_nl_compat_dumpit() doesn't handle the error returned from cmd
header function. It means even when the check added in that fix fails, it
won't stop calling tipc_nl_compat_name_table_dump(), and the issue will be
triggered again.

So this patch is to add the process for the err returned from cmd header
function in tipc_nl_compat_dumpit().

Reported-by: syzbot+3ce8520484b0d4e260a5@syzkaller.appspotmail.com
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

A similar issue as fixed by Patch "tipc: check bearer name with right
length in tipc_nl_compat_bearer_enable" was also found by syzbot in
tipc_nl_compat_link_set().

The length to check with should be 'TLV_GET_DATA_LEN(msg->req) -
offsetof(struct tipc_link_config, name)'.

Reported-by: syzbot+de00a87b8644a582ae79@syzkaller.appspotmail.com
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Syzbot reported the following crash:

BUG: KMSAN: uninit-value in memchr+0xce/0x110 lib/string.c:961
  memchr+0xce/0x110 lib/string.c:961
  string_is_valid net/tipc/netlink_compat.c:176 [inline]
  tipc_nl_compat_bearer_enable+0x2c4/0x910 net/tipc/netlink_compat.c:401
  __tipc_nl_compat_doit net/tipc/netlink_compat.c:321 [inline]
  tipc_nl_compat_doit+0x3aa/0xaf0 net/tipc/netlink_compat.c:354
  tipc_nl_compat_handle net/tipc/netlink_compat.c:1162 [inline]
  tipc_nl_compat_recv+0x1ae7/0x2750 net/tipc/netlink_compat.c:1265
  genl_family_rcv_msg net/netlink/genetlink.c:601 [inline]
  genl_rcv_msg+0x185f/0x1a60 net/netlink/genetlink.c:626
  netlink_rcv_skb+0x431/0x620 net/netlink/af_netlink.c:2477
  genl_rcv+0x63/0x80 net/netlink/genetlink.c:637
  netlink_unicast_kernel net/netlink/af_netlink.c:1310 [inline]
  netlink_unicast+0xf3e/0x1020 net/netlink/af_netlink.c:1336
  netlink_sendmsg+0x127f/0x1300 net/netlink/af_netlink.c:1917
  sock_sendmsg_nosec net/socket.c:622 [inline]
  sock_sendmsg net/socket.c:632 [inline]

Uninit was created at:
  __alloc_skb+0x309/0xa20 net/core/skbuff.c:208
  alloc_skb include/linux/skbuff.h:1012 [inline]
  netlink_alloc_large_skb net/netlink/af_netlink.c:1182 [inline]
  netlink_sendmsg+0xb82/0x1300 net/netlink/af_netlink.c:1892
  sock_sendmsg_nosec net/socket.c:622 [inline]
  sock_sendmsg net/socket.c:632 [inline]

It was triggered when the bearer name size < TIPC_MAX_BEARER_NAME,
it would check with a wrong len/TLV_GET_DATA_LEN(msg->req), which
also includes priority and disc_domain length.

This patch is to fix it by checking it with a right length:
'TLV_GET_DATA_LEN(msg->req) - offsetof(struct tipc_bearer_config, name)'.

Reported-by: syzbot+8b707430713eb46e1e45@syzkaller.appspotmail.com
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The number of stubs is growing and has nothing to do with addrconf.
Move the definition of the stubs to a separate header file and update
users. In the move, drop the vxlan specific comment before ipv6_stub.

Code move only; no functional change intended.
Signed-off-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix the return value check which testing the wrong variable
in tipc_mcast_send_sync().

Fixes: c55c8eda ("tipc: smooth change between replicast and broadcast")
Reported-by: NHulk Robot <hulkci@huawei.com>
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>

When running a syz script, a panic occurred:

[  156.088228] BUG: KASAN: use-after-free in tipc_disc_timeout+0x9c9/0xb20 [tipc]
[  156.094315] Call Trace:
[  156.094844]  <IRQ>
[  156.095306]  dump_stack+0x7c/0xc0
[  156.097346]  print_address_description+0x65/0x22e
[  156.100445]  kasan_report.cold.3+0x37/0x7a
[  156.102402]  tipc_disc_timeout+0x9c9/0xb20 [tipc]
[  156.106517]  call_timer_fn+0x19a/0x610
[  156.112749]  run_timer_softirq+0xb51/0x1090

It was caused by the netns freed without deleting the discoverer timer,
while later on the netns would be accessed in the timer handler.

The timer should have been deleted by tipc_net_stop() when cleaning up a
netns. However, tipc has been able to enable a bearer and start d->timer
without the local node_addr set since Commit 52dfae5c ("tipc: obtain
node identity from interface by default"), which caused the timer not to
be deleted in tipc_net_stop() then.

So fix it in tipc_net_stop() by changing to check local node_id instead
of local node_addr, as Jon suggested.

While at it, remove the calling of tipc_nametbl_withdraw() there, since
tipc_nametbl_stop() will take of the nametbl's freeing after.

Fixes: 52dfae5c ("tipc: obtain node identity from interface by default")
Reported-by: syzbot+a25307ad099309f1c2b9@syzkaller.appspotmail.com
Signed-off-by: NXin Long <lucien.xin@gmail.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When checking the code with clang -Wsometimes-uninitialized we get the
following warning:

if (!tipc_link_is_establishing(l)) {
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/tipc/node.c:847:46: note: uninitialized use occurs here
      tipc_bearer_xmit(n->net, bearer_id, &xmitq, maddr);

net/tipc/node.c:831:2: note: remove the 'if' if its condition is always
true
if (!tipc_link_is_establishing(l)) {
    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/tipc/node.c:821:31: note: initialize the variable 'maddr' to silence
this warning
struct tipc_media_addr *maddr;

We fix this by initializing 'maddr' to NULL. For the matter of clarity,
we also test if 'xmitq' is non-empty before we use it and 'maddr'
further down in the  function. It will never happen that 'xmitq' is non-
empty at the same time as 'maddr' is NULL, so this is a sufficient test.

Fixes: 598411d7 ("tipc: make resetting of links non-atomic")
Reported-by: NNathan Chancellor <natechancellor@gmail.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since maxattr is common, the policy can't really differ sanely,
so make it common as well.

The only user that did in fact manage to make a non-common policy
is taskstats, which has to be really careful about it (since it's
still using a common maxattr!). This is no longer supported, but
we can fake it using pre_doit.

This reduces the size of e.g. nl80211.o (which has lots of commands):

   text	   data	    bss	    dec	    hex	filename
 398745	  14323	   2240	 415308	  6564c	net/wireless/nl80211.o (before)
 397913	  14331	   2240	 414484	  65314	net/wireless/nl80211.o (after)
--------------------------------
   -832      +8       0    -824

Which is obviously just 8 bytes for each command, and an added 8
bytes for the new policy pointer. I'm not sure why the ops list is
counted as .text though.

Most of the code transformations were done using the following spatch:
    @ops@
    identifier OPS;
    expression POLICY;
    @@
    struct genl_ops OPS[] = {
    ...,
     {
    -	.policy = POLICY,
     },
    ...
    };

    @@
    identifier ops.OPS;
    expression ops.POLICY;
    identifier fam;
    expression M;
    @@
    struct genl_family fam = {
            .ops = OPS,
            .maxattr = M,
    +       .policy = POLICY,
            ...
    };

This also gets rid of devlink_nl_cmd_region_read_dumpit() accessing
the cb->data as ops, which we want to change in a later genl patch.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In commit c55c8eda ("tipc: smooth change between replicast and
broadcast") we introduced new method to eliminate the risk of message
reordering that happen in between different nodes.
Unfortunately, we forgot checking at receiving side to ignore intra node.

We fix this by checking and returning if arrived message from intra node.

syzbot report:

==================================================================
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 7820 Comm: syz-executor418 Not tainted 5.0.0+ #61
Hardware name: Google Google Compute Engine/Google Compute Engine,
BIOS Google 01/01/2011
RIP: 0010:tipc_mcast_filter_msg+0x21b/0x13d0 net/tipc/bcast.c:782
Code: 45 c0 0f 84 39 06 00 00 48 89 5d 98 e8 ce ab a5 fa 49 8d bc
 24 c8 00 00 00 48 b9 00 00 00 00 00 fc ff df 48 89 f8 48 c1 e8 03
 <80> 3c 08 00 0f 85 9a 0e 00 00 49 8b 9c 24 c8 00 00 00 48 be 00 00
RSP: 0018:ffff8880959defc8 EFLAGS: 00010202
RAX: 0000000000000019 RBX: ffff888081258a48 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: ffffffff86cab862 RDI: 00000000000000c8
RBP: ffff8880959df030 R08: ffff8880813d0200 R09: ffffed1015d05bc8
R10: ffffed1015d05bc7 R11: ffff8880ae82de3b R12: 0000000000000000
R13: 000000000000002c R14: 0000000000000000 R15: ffff888081258a48
FS:  000000000106a880(0000) GS:ffff8880ae800000(0000)
 knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020001cc0 CR3: 0000000094a20000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 tipc_sk_filter_rcv+0x182d/0x34f0 net/tipc/socket.c:2168
 tipc_sk_enqueue net/tipc/socket.c:2254 [inline]
 tipc_sk_rcv+0xc45/0x25a0 net/tipc/socket.c:2305
 tipc_sk_mcast_rcv+0x724/0x1020 net/tipc/socket.c:1209
 tipc_mcast_xmit+0x7fe/0x1200 net/tipc/bcast.c:410
 tipc_sendmcast+0xb36/0xfc0 net/tipc/socket.c:820
 __tipc_sendmsg+0x10df/0x18d0 net/tipc/socket.c:1358
 tipc_sendmsg+0x53/0x80 net/tipc/socket.c:1291
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xdd/0x130 net/socket.c:661
 ___sys_sendmsg+0x806/0x930 net/socket.c:2260
 __sys_sendmsg+0x105/0x1d0 net/socket.c:2298
 __do_sys_sendmsg net/socket.c:2307 [inline]
 __se_sys_sendmsg net/socket.c:2305 [inline]
 __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2305
 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4401c9
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8
 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05
 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffd887fa9d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401c9
RDX: 0000000000000000 RSI: 0000000020002140 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401a50
R13: 0000000000401ae0 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace ba79875754e1708f ]---

Reported-by: syzbot+be4bdf2cc3e85e952c50@syzkaller.appspotmail.com
Fixes: c55c8eda ("tipc: smooth change between replicast and broadcast")
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>

skb free-ed in:
  1/ condition 1: tipc_sk_filter_rcv -> tipc_sk_proto_rcv
  2/ condition 2: tipc_sk_filter_rcv -> tipc_group_filter_msg
This leads to a "use-after-free" access in the next condition.

We fix this by intializing the variable at declaration, then it is safe
to check this variable to continue processing if condition matches.

syzbot report:

==================================================================
BUG: KASAN: use-after-free in tipc_sk_filter_rcv+0x2166/0x34f0
 net/tipc/socket.c:2167
Read of size 4 at addr ffff88808ea58534 by task kworker/u4:0/7

CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.0.0+ #61
Hardware name: Google Google Compute Engine/Google Compute Engine,
 BIOS Google 01/01/2011
Workqueue: tipc_send tipc_conn_send_work
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187
 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131
 tipc_sk_filter_rcv+0x2166/0x34f0 net/tipc/socket.c:2167
 tipc_sk_enqueue net/tipc/socket.c:2254 [inline]
 tipc_sk_rcv+0xc45/0x25a0 net/tipc/socket.c:2305
 tipc_topsrv_kern_evt+0x3b7/0x580 net/tipc/topsrv.c:610
 tipc_conn_send_to_sock+0x43e/0x5f0 net/tipc/topsrv.c:283
 tipc_conn_send_work+0x65/0x80 net/tipc/topsrv.c:303
 process_one_work+0x98e/0x1790 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x357/0x430 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352

Reported-by: syzbot+e863893591cc7a622e40@syzkaller.appspotmail.com
Fixes: c55c8eda ("tipc: smooth change between replicast and broadcast")
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>

When cancelling a subscription, we have to clear the cancel bit in the
request before iterating over any established subscriptions with memcmp.
Otherwise no subscription will ever be found, and it will not be
possible to explicitly unsubscribe individual subscriptions.

Fixes: 8985ecc7 ("tipc: simplify endianness handling in topology subscriber")
Signed-off-by: NErik Hugne <erik.hugne@gmail.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently, a multicast stream may start out using replicast, because
there are few destinations, and then it should ideally switch to
L2/broadcast IGMP/multicast when the number of destinations grows beyond
a certain limit. The opposite should happen when the number decreases
below the limit.

To eliminate the risk of message reordering caused by method change,
a sending socket must stick to a previously selected method until it
enters an idle period of 5 seconds. Means there is a 5 seconds pause
in the traffic from the sender socket.

If the sender never makes such a pause, the method will never change,
and transmission may become very inefficient as the cluster grows.

With this commit, we allow such a switch between replicast and
broadcast without any need for a traffic pause.

Solution is to send a dummy message with only the header, also with
the SYN bit set, via broadcast or replicast. For the data message,
the SYN bit is set and sending via replicast or broadcast (inverse
method with dummy).

Then, at receiving side any messages follow first SYN bit message
(data or dummy message), they will be held in deferred queue until
another pair (dummy or data message) arrived in other link.

v2: reverse christmas tree declaration
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>

As a preparation for introducing a smooth switching between replicast
and broadcast method for multicast message, We have to introduce a new
capability flag TIPC_MCAST_RBCTL to handle this new feature.

During a cluster upgrade a node can come back with this new capabilities
which also must be reflected in the cluster capabilities field.
The new feature is only applicable if all node in the cluster supports
this new capability.
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, a multicast stream uses either broadcast or replicast as
transmission method, based on the ratio between number of actual
destinations nodes and cluster size.

However, when an L2 interface (e.g., VXLAN) provides pseudo
broadcast support, this becomes very inefficient, as it blindly
replicates multicast packets to all cluster/subnet nodes,
irrespective of whether they host actual target sockets or not.

The TIPC multicast algorithm is able to distinguish real destination
nodes from other nodes, and hence provides a smarter and more
efficient method for transferring multicast messages than
pseudo broadcast can do.

Because of this, we now make it possible for users to force
the broadcast link to permanently switch to using replicast,
irrespective of which capabilities the bearer provides,
or pretend to provide.
Conversely, we also make it possible to force the broadcast link
to always use true broadcast. While maybe less useful in
deployed systems, this may at least be useful for testing the
broadcast algorithm in small clusters.

We retain the current AUTOSELECT ability, i.e., to let the broadcast link
automatically select which algorithm to use, and to switch back and forth
between broadcast and replicast as the ratio between destination
node number and cluster size changes. This remains the default method.

Furthermore, we make it possible to configure the threshold ratio for
such switches. The default ratio is now set to 10%, down from 25% in the
earlier implementation.
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>

We move the check that prevents connecting service ranges to after
the RDM/DGRAM check, and move address sanity control to a separate
function that also validates the service range.

Fixes: 23998835 ("tipc: improve address sanity check in tipc_connect()")
Signed-off-by: NErik Hugne <erik.hugne@gmail.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

nla_nest_start may fail. The fix check its status and returns
-EMSGSIZE in case it fails.
Signed-off-by: NKangjie Lu <kjlu@umn.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

nla_nest_start could fail and requires a check. The fix returns
-EMSGSIZE if it fails.
Signed-off-by: NKangjie Lu <kjlu@umn.edu>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix regression bug introduced in
commit 365ad353 ("tipc: reduce risk of user starvation during link
congestion")

Only signal -EDESTADDRREQ for RDM/DGRAM if we don't have a cached
sockaddr.

Fixes: 365ad353 ("tipc: reduce risk of user starvation during link congestion")
Signed-off-by: NErik Hugne <erik.hugne@gmail.com>
Signed-off-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When sending multicast messages via blocking socket,
if sending link is congested (tsk->cong_link_cnt is set to 1),
the sending thread will be put into sleeping state. However,
tipc_sk_filter_rcv() is called under socket spin lock but
tipc_wait_for_cond() is not. So, there is no guarantee that
the setting of tsk->cong_link_cnt to 0 in tipc_sk_proto_rcv() in
CPU-1 will be perceived by CPU-0. If that is the case, the sending
thread in CPU-0 after being waken up, will continue to see
tsk->cong_link_cnt as 1 and put the sending thread into sleeping
state again. The sending thread will sleep forever.

CPU-0                                | CPU-1
tipc_wait_for_cond()                 |
{                                    |
 // condition_ = !tsk->cong_link_cnt |
 while ((rc_ = !(condition_))) {     |
  ...                                |
  release_sock(sk_);                 |
  wait_woken();                      |
                                     | if (!sock_owned_by_user(sk))
                                     |  tipc_sk_filter_rcv()
                                     |  {
                                     |   ...
                                     |   tipc_sk_proto_rcv()
                                     |   {
                                     |    ...
                                     |    tsk->cong_link_cnt--;
                                     |    ...
                                     |    sk->sk_write_space(sk);
                                     |    ...
                                     |   }
                                     |   ...
                                     |  }
  sched_annotate_sleep();            |
  lock_sock(sk_);                    |
  remove_wait_queue();               |
 }                                   |
}                                    |

This commit fixes it by adding memory barrier to tipc_sk_proto_rcv()
and tipc_wait_for_cond().
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTung Nguyen <tung.q.nguyen@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This commit replaces schedule_timeout() with wait_woken()
in function tipc_wait_for_rcvmsg(). wait_woken() uses
memory barriers in its implementation to avoid potential
race condition when putting a process into sleeping state
and then waking it up.
Acked-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTung Nguyen <tung.q.nguyen@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit 844cf763 ("tipc: make macro tipc_wait_for_cond() smp safe")
replaced finish_wait() with remove_wait_queue() but still used
prepare_to_wait(). This causes unnecessary conditional
checking  before adding to wait queue in prepare_to_wait().

This commit replaces prepare_to_wait() with add_wait_queue()
as the pair function with remove_wait_queue().
Acked-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Signed-off-by: NTung Nguyen <tung.q.nguyen@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When a link endpoint is re-created (e.g. after a node reboot or
interface reset), the link session number is varied by random, the peer
endpoint will be synced with this new session number before the link is
re-established.

However, there is a shortcoming in this mechanism that can lead to the
link never re-established or faced with a failure then. It happens when
the peer endpoint is ready in ESTABLISHING state, the 'peer_session' as
well as the 'in_session' flag have been set, but suddenly this link
endpoint leaves. When it comes back with a random session number, there
are two situations possible:

1/ If the random session number is larger than (or equal to) the
previous one, the peer endpoint will be updated with this new session
upon receipt of a RESET_MSG from this endpoint, and the link can be re-
established as normal. Otherwise, all the RESET_MSGs from this endpoint
will be rejected by the peer. In turn, when this link endpoint receives
one ACTIVATE_MSG from the peer, it will move to ESTABLISHED and start
to send STATE_MSGs, but again these messages will be dropped by the
peer due to wrong session.
The peer link endpoint can still become ESTABLISHED after receiving a
traffic message from this endpoint (e.g. a BCAST_PROTOCOL or
NAME_DISTRIBUTOR), but since all the STATE_MSGs are invalid, the link
will be forced down sooner or later!

Even in case the random session number is larger than the previous one,
it can be that the ACTIVATE_MSG from the peer arrives first, and this
link endpoint moves quickly to ESTABLISHED without sending out any
RESET_MSG yet. Consequently, the peer link will not be updated with the
new session number, and the same link failure scenario as above will
happen.

2/ Another situation can be that, the peer link endpoint was reset due
to any reasons in the meantime, its link state was set to RESET from
ESTABLISHING but still in session, i.e. the 'in_session' flag is not
reset...
Now, if the random session number from this endpoint is less than the
previous one, all the RESET_MSGs from this endpoint will be rejected by
the peer. In the other direction, when this link endpoint receives a
RESET_MSG from the peer, it moves to ESTABLISHING and starts to send
ACTIVATE_MSGs, but all these messages will be rejected by the peer too.
As a result, the link cannot be re-established but gets stuck with this
link endpoint in state ESTABLISHING and the peer in RESET!

Solution:

===========

This link endpoint should not go directly to ESTABLISHED when getting
ACTIVATE_MSG from the peer which may belong to the old session if the
link was re-created. To ensure the session to be correct before the
link is re-established, the peer endpoint in ESTABLISHING state will
send back the last session number in ACTIVATE_MSG for a verification at
this endpoint. Then, if needed, a new and more appropriate session
number will be regenerated to force a re-synch first.

In addition, when a link in ESTABLISHING state is reset, its state will
move to RESET according to the link FSM, along with resetting the
'in_session' flag (and the other data) as a normal link reset, it will
also be deleted if requested.

The solution is backward compatible.
Acked-by: NJon Maloy <jon.maloy@ericsson.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NTuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When we free skb at tipc_data_input, we return a 'false' boolean.
Then, skb passed to subcalling tipc_link_input in tipc_link_rcv,

<snip>
1303 int tipc_link_rcv:
...
1354    if (!tipc_data_input(l, skb, l->inputq))
1355        rc |= tipc_link_input(l, skb, l->inputq);
</snip>

Fix it by simple changing to a 'true' boolean when skb is being free-ed.
Then, tipc_link_rcv will bypassed to subcalling tipc_link_input as above
condition.
Acked-by: NYing Xue <ying.xue@windriver.com>
Acked-by: NJon Maloy <maloy@donjonn.com>
Signed-off-by: NHoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

max_rcvbuf_size is no longer used since commit "414574a0".
Signed-off-by: NZhaolong Zhang <zhangzl2013@126.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

In preparation to enabling -Wimplicit-fallthrough, mark switch cases
where we are expecting to fall through.

This patch fixes the following warnings:

net/tipc/link.c:1125:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
net/tipc/socket.c:736:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
net/tipc/socket.c:2418:7: warning: this statement may fall through [-Wimplicit-fallthrough=]

Warning level 3 was used: -Wimplicit-fallthrough=3

This patch is part of the ongoing efforts to enabling
-Wimplicit-fallthrough.
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Remove unneeded semicolon
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

BUG: KMSAN: uninit-value in tipc_nl_compat_doit+0x404/0xa10 net/tipc/netlink_compat.c:335
CPU: 0 PID: 4514 Comm: syz-executor485 Not tainted 4.16.0+ #87
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683
 tipc_nl_compat_doit+0x404/0xa10 net/tipc/netlink_compat.c:335
 tipc_nl_compat_recv+0x164b/0x2700 net/tipc/netlink_compat.c:1153
 genl_family_rcv_msg net/netlink/genetlink.c:599 [inline]
 genl_rcv_msg+0x1686/0x1810 net/netlink/genetlink.c:624
 netlink_rcv_skb+0x378/0x600 net/netlink/af_netlink.c:2447
 genl_rcv+0x63/0x80 net/netlink/genetlink.c:635
 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline]
 netlink_unicast+0x166b/0x1740 net/netlink/af_netlink.c:1337
 netlink_sendmsg+0x1048/0x1310 net/netlink/af_netlink.c:1900
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046
 __sys_sendmsg net/socket.c:2080 [inline]
 SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091
 SyS_sendmsg+0x54/0x80 net/socket.c:2087
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x43fda9
RSP: 002b:00007ffd0c184ba8 EFLAGS: 00000213 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fda9
RDX: 0000000000000000 RSI: 0000000020023000 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8
R10: 00000000004002c8 R11: 0000000000000213 R12: 00000000004016d0
R13: 0000000000401760 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:278 [inline]
 kmsan_internal_poison_shadow+0xb8/0x1b0 mm/kmsan/kmsan.c:188
 kmsan_kmalloc+0x94/0x100 mm/kmsan/kmsan.c:314
 kmsan_slab_alloc+0x11/0x20 mm/kmsan/kmsan.c:321
 slab_post_alloc_hook mm/slab.h:445 [inline]
 slab_alloc_node mm/slub.c:2737 [inline]
 __kmalloc_node_track_caller+0xaed/0x11c0 mm/slub.c:4369
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x2cf/0x9f0 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:984 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1183 [inline]
 netlink_sendmsg+0x9a6/0x1310 net/netlink/af_netlink.c:1875
 sock_sendmsg_nosec net/socket.c:630 [inline]
 sock_sendmsg net/socket.c:640 [inline]
 ___sys_sendmsg+0xec0/0x1310 net/socket.c:2046
 __sys_sendmsg net/socket.c:2080 [inline]
 SYSC_sendmsg+0x2a3/0x3d0 net/socket.c:2091
 SyS_sendmsg+0x54/0x80 net/socket.c:2087
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2

In tipc_nl_compat_recv(), when the len variable returned by
nlmsg_attrlen() is 0, the message is still treated as a valid one,
which is obviously unresonable. When len is zero, it means the
message not only doesn't contain any valid TLV payload, but also
TLV header is not included. Under this stituation, tlv_type field
in TLV header is still accessed in tipc_nl_compat_dumpit() or
tipc_nl_compat_doit(), but the field space is obviously illegal.
Of course, it is not initialized.

Reported-by: syzbot+bca0dc46634781f08b38@syzkaller.appspotmail.com
Reported-by: syzbot+6bdb590321a7ae40c1a6@syzkaller.appspotmail.com
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

syzbot reported:

BUG: KMSAN: uninit-value in __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline]
BUG: KMSAN: uninit-value in __fswab32 include/uapi/linux/swab.h:59 [inline]
BUG: KMSAN: uninit-value in tipc_nl_compat_name_table_dump+0x4a8/0xba0 net/tipc/netlink_compat.c:826
CPU: 0 PID: 6290 Comm: syz-executor848 Not tainted 4.19.0-rc8+ #70
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x306/0x460 lib/dump_stack.c:113
 kmsan_report+0x1a2/0x2e0 mm/kmsan/kmsan.c:917
 __msan_warning+0x7c/0xe0 mm/kmsan/kmsan_instr.c:500
 __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline]
 __fswab32 include/uapi/linux/swab.h:59 [inline]
 tipc_nl_compat_name_table_dump+0x4a8/0xba0 net/tipc/netlink_compat.c:826
 __tipc_nl_compat_dumpit+0x59e/0xdb0 net/tipc/netlink_compat.c:205
 tipc_nl_compat_dumpit+0x63a/0x820 net/tipc/netlink_compat.c:270
 tipc_nl_compat_handle net/tipc/netlink_compat.c:1151 [inline]
 tipc_nl_compat_recv+0x1402/0x2760 net/tipc/netlink_compat.c:1210
 genl_family_rcv_msg net/netlink/genetlink.c:601 [inline]
 genl_rcv_msg+0x185c/0x1a20 net/netlink/genetlink.c:626
 netlink_rcv_skb+0x394/0x640 net/netlink/af_netlink.c:2454
 genl_rcv+0x63/0x80 net/netlink/genetlink.c:637
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x166d/0x1720 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x1391/0x1420 net/netlink/af_netlink.c:1908
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 ___sys_sendmsg+0xe47/0x1200 net/socket.c:2116
 __sys_sendmsg net/socket.c:2154 [inline]
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg+0x307/0x460 net/socket.c:2161
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
 do_syscall_64+0xbe/0x100 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x440179
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffecec49318 EFLAGS: 00000213 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440179
RDX: 0000000000000000 RSI: 0000000020000100 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8
R10: 0000000000000000 R11: 0000000000000213 R12: 0000000000401a00
R13: 0000000000401a90 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:255 [inline]
 kmsan_internal_poison_shadow+0xc8/0x1d0 mm/kmsan/kmsan.c:180
 kmsan_kmalloc+0xa4/0x120 mm/kmsan/kmsan_hooks.c:104
 kmsan_slab_alloc+0x10/0x20 mm/kmsan/kmsan_hooks.c:113
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2727 [inline]
 __kmalloc_node_track_caller+0xb43/0x1400 mm/slub.c:4360
 __kmalloc_reserve net/core/skbuff.c:138 [inline]
 __alloc_skb+0x422/0xe90 net/core/skbuff.c:206
 alloc_skb include/linux/skbuff.h:996 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1189 [inline]
 netlink_sendmsg+0xcaf/0x1420 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 ___sys_sendmsg+0xe47/0x1200 net/socket.c:2116
 __sys_sendmsg net/socket.c:2154 [inline]
 __do_sys_sendmsg net/socket.c:2163 [inline]
 __se_sys_sendmsg+0x307/0x460 net/socket.c:2161
 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2161
 do_syscall_64+0xbe/0x100 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

We cannot take for granted the thing that the length of data contained
in TLV is longer than the size of struct tipc_name_table_query in
tipc_nl_compat_name_table_dump().

Reported-by: syzbot+06e771a754829716a327@syzkaller.appspotmail.com
Signed-off-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>