commit 517d7c79bd ("tipc: fix hanging poll() for stream sockets")
introduced a regression for clients using non-blocking sockets.
After the commit, we send EPOLLOUT event to the client even in
TIPC_CONNECTING state. This causes the subsequent send() to fail
with ENOTCONN, as the socket is still not in TIPC_ESTABLISHED state.
In this commit, we:
- improve the fix for hanging poll() by replacing sk_data_ready()
with sk_state_change() to wake up all clients.
- revert the faulty updates introduced by commit 517d7c79bd
("tipc: fix hanging poll() for stream sockets").
Fixes: 517d7c79bd ("tipc: fix hanging poll() for stream sockets")
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@gmail.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.se>
Signed-off-by: David S. Miller <davem@davemloft.net>
TIPC link can temporarily fall into "half-establish" that only one of
the link endpoints is ESTABLISHED and starts to send traffic, PROTOCOL
messages, whereas the other link endpoint is not up (e.g. immediately
when the endpoint receives ACTIVATE_MSG, the network interface goes
down...).
This is a normal situation and will be settled because the link
endpoint will be eventually brought down after the link tolerance time.
However, the situation will become worse when the second link is
established before the first link endpoint goes down,
For example:
1. Both links <1A-2A>, <1B-2B> down
2. Link endpoint 2A up, but 1A still down (e.g. due to network
disturbance, wrong session, etc.)
3. Link <1B-2B> up
4. Link endpoint 2A down (e.g. due to link tolerance timeout)
5. Node B starts failover onto link <1B-2B>
==> Node A does never start link failover.
When the "half-failover" situation happens, two consequences have been
observed:
a) Peer link/node gets stuck in FAILINGOVER state;
b) Traffic or user messages that peer node is trying to failover onto
the second link can be partially or completely dropped by this node.
The consequence a) was actually solved by commit c140eb166d ("tipc:
fix failover problem"), but that commit didn't cover the b). It's due
to the fact that the tunnel link endpoint has never been prepared for a
failover, so the 'l->drop_point' (and the other data...) is not set
correctly. When a TUNNEL_MSG from peer node arrives on the link,
depending on the inner message's seqno and the current 'l->drop_point'
value, the message can be dropped (- treated as a duplicate message) or
processed.
At this early stage, the traffic messages from peer are likely to be
NAME_DISTRIBUTORs, this means some name table entries will be missed on
the node forever!
The commit resolves the issue by starting the FAILOVER process on this
node as well. Another benefit from this solution is that we ensure the
link will not be re-established until the failover ends.
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add options to strictly validate messages and dump messages,
sometimes perhaps validating dump messages non-strictly may
be required, so add an option for that as well.
Since none of this can really be applied to existing commands,
set the options everwhere using the following spatch:
@@
identifier ops;
expression X;
@@
struct genl_ops ops[] = {
...,
{
.cmd = X,
+ .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
...
},
...
};
For new commands one should just not copy the .validate 'opt-out'
flags and thus get strict validation.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
We currently have two levels of strict validation:
1) liberal (default)
- undefined (type >= max) & NLA_UNSPEC attributes accepted
- attribute length >= expected accepted
- garbage at end of message accepted
2) strict (opt-in)
- NLA_UNSPEC attributes accepted
- attribute length >= expected accepted
Split out parsing strictness into four different options:
* TRAILING - check that there's no trailing data after parsing
attributes (in message or nested)
* MAXTYPE - reject attrs > max known type
* UNSPEC - reject attributes with NLA_UNSPEC policy entries
* STRICT_ATTRS - strictly validate attribute size
The default for future things should be *everything*.
The current *_strict() is a combination of TRAILING and MAXTYPE,
and is renamed to _deprecated_strict().
The current regular parsing has none of this, and is renamed to
*_parse_deprecated().
Additionally it allows us to selectively set one of the new flags
even on old policies. Notably, the UNSPEC flag could be useful in
this case, since it can be arranged (by filling in the policy) to
not be an incompatible userspace ABI change, but would then going
forward prevent forgetting attribute entries. Similar can apply
to the POLICY flag.
We end up with the following renames:
* nla_parse -> nla_parse_deprecated
* nla_parse_strict -> nla_parse_deprecated_strict
* nlmsg_parse -> nlmsg_parse_deprecated
* nlmsg_parse_strict -> nlmsg_parse_deprecated_strict
* nla_parse_nested -> nla_parse_nested_deprecated
* nla_validate_nested -> nla_validate_nested_deprecated
Using spatch, of course:
@@
expression TB, MAX, HEAD, LEN, POL, EXT;
@@
-nla_parse(TB, MAX, HEAD, LEN, POL, EXT)
+nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT)
@@
expression NLH, HDRLEN, TB, MAX, POL, EXT;
@@
-nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT)
+nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT)
@@
expression NLH, HDRLEN, TB, MAX, POL, EXT;
@@
-nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
+nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
@@
expression TB, MAX, NLA, POL, EXT;
@@
-nla_parse_nested(TB, MAX, NLA, POL, EXT)
+nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT)
@@
expression START, MAX, POL, EXT;
@@
-nla_validate_nested(START, MAX, POL, EXT)
+nla_validate_nested_deprecated(START, MAX, POL, EXT)
@@
expression NLH, HDRLEN, MAX, POL, EXT;
@@
-nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT)
+nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT)
For this patch, don't actually add the strict, non-renamed versions
yet so that it breaks compile if I get it wrong.
Also, while at it, make nla_validate and nla_parse go down to a
common __nla_validate_parse() function to avoid code duplication.
Ultimately, this allows us to have very strict validation for every
new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the
next patch, while existing things will continue to work as is.
In effect then, this adds fully strict validation for any new command.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David 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: 4109a2c3b9 ("tipc: tipc_udp_recv() cleanup vs rcu verbs")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: David 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: Eric Dumazet <edumazet@google.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David 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: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David 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: cc79dd1ba9 ("tipc: change socket buffer overflow control to respect sk_rcvbuf")
Fixes: a5325ae5b8 ("tipc: add name distributor resiliency queue")
Signed-off-by: Jie Liu <liujie165@huawei.com>
Reported-by: Qiang Ning <ningqiang1@huawei.com>
Reviewed-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Reviewed-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: David 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 91986ee166 ("tipc: fix link session and
re-establish issues") by simply varying the link 'peer_session' value
at the link_reset().
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David 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: 40999f11ce ("tipc: make link capability update thread safe")
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David 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: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Minor comment merge conflict in mlx5.
Staging driver has a fixup due to the skb->xmit_more changes
in 'net-next', but was removed in 'net'.
Signed-off-by: David 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: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David 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: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David 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: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David 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: c55c8edafa ("tipc: smooth change between replicast and broadcast")
Reported-by: Tuong Lien Tong <tuong.t.lien@dektech.com.au>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David 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 974cb0e3e7 ("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: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David 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: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David 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: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David 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: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix the return value check which testing the wrong variable
in tipc_mcast_send_sync().
Fixes: c55c8edafa ("tipc: smooth change between replicast and broadcast")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David 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 52dfae5c85 ("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: 52dfae5c85 ("tipc: obtain node identity from interface by default")
Reported-by: syzbot+a25307ad099309f1c2b9@syzkaller.appspotmail.com
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David 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: 598411d70f ("tipc: make resetting of links non-atomic")
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David 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: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David 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: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David 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: 8985ecc7c1 ("tipc: simplify endianness handling in topology subscriber")
Signed-off-by: Erik Hugne <erik.hugne@gmail.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David 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: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David 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: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David 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: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David 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: 23998835be ("tipc: improve address sanity check in tipc_connect()")
Signed-off-by: Erik Hugne <erik.hugne@gmail.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David 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: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
nla_nest_start could fail and requires a check. The fix returns
-EMSGSIZE if it fails.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix regression bug introduced in
commit 365ad353c2 ("tipc: reduce risk of user starvation during link
congestion")
Only signal -EDESTADDRREQ for RDM/DGRAM if we don't have a cached
sockaddr.
Fixes: 365ad353c2 ("tipc: reduce risk of user starvation during link congestion")
Signed-off-by: Erik Hugne <erik.hugne@gmail.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David 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: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Three conflicts, one of which, for marvell10g.c is non-trivial and
requires some follow-up from Heiner or someone else.
The issue is that Heiner converted the marvell10g driver over to
use the generic c45 code as much as possible.
However, in 'net' a bug fix appeared which makes sure that a new
local mask (MDIO_AN_10GBT_CTRL_ADV_NBT_MASK) with value 0x01e0
is cleared.
Signed-off-by: David 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: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 844cf763fb ("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: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The netfilter conflicts were rather simple overlapping
changes.
However, the cls_tcindex.c stuff was a bit more complex.
On the 'net' side, Cong is fixing several races and memory
leaks. Whilst on the 'net-next' side we have Vlad adding
the rtnl-ness support.
What I've decided to do, in order to resolve this, is revert the
conversion over to using a workqueue that Cong did, bringing us back
to pure RCU. I did it this way because I believe that either Cong's
races don't apply with have Vlad did things, or Cong will have to
implement the race fix slightly differently.
Signed-off-by: David 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: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: David 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: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <maloy@donjonn.com>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
max_rcvbuf_size is no longer used since commit "414574a0af36".
Signed-off-by: Zhaolong Zhang <zhangzl2013@126.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David 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: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David 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: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Parthasarathy Bhuvaragan
Tuong Lien
Johannes Berg
Michal Kubecek
Eric Dumazet
Tung Nguyen
David S. Miller
Jie Liu
Jon Maloy
Hoang Le
Xin Long
David Ahern
Wei Yongjun
Erik Hugne
Kangjie Lu
Zhaolong Zhang
Gustavo A. R. Silva
YueHaibing
Ying Xue