Commit Graph

1505 Commits

Author SHA1 Message Date
YueHaibing d4fb30f6f1 tipc: remove unneeded semicolon in trace.c
Remove unneeded semicolon

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17 22:04:43 -08:00
Gustavo A. R. Silva f87d8ad923 tipc: fix memory leak in tipc_nl_compat_publ_dump
There is a memory leak in case genlmsg_put fails.

Fix this by freeing *args* before return.

Addresses-Coverity-ID: 1476406 ("Resource leak")
Fixes: 46273cf7e0 ("tipc: fix a missing check of genlmsg_put")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-07 11:42:08 -05:00
Kangjie Lu 46273cf7e0 tipc: fix a missing check of genlmsg_put
genlmsg_put could fail. The fix inserts a check of its return value, and
if it fails, returns -EMSGSIZE.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-27 16:26:09 -08:00
Cong Wang dc4501ff28 tipc: fix a double free in tipc_enable_bearer()
bearer_disable() already calls kfree_rcu() to free struct tipc_bearer,
we don't need to call kfree() again.

Fixes: cb30a63384 ("tipc: refactor function tipc_enable_bearer()")
Reported-by: syzbot+b981acf1fb240c0c128b@syzkaller.appspotmail.com
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-27 16:16:17 -08:00
David S. Miller 90cadbbf34 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Pull in bug fixes before respinning my net-next pull
request.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-24 16:19:56 -08:00
Aditya Pakki 89dfd00837 net/netlink_compat: Fix a missing check of nla_parse_nested
In tipc_nl_compat_sk_dump(), if nla_parse_nested() fails, it could return
an error. To be consistent with other invocations of the function call,
on error, the fix passes the return value upstream.

Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-24 14:42:11 -08:00
David S. Miller 2be09de7d6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Lots of conflicts, by happily all cases of overlapping
changes, parallel adds, things of that nature.

Thanks to Stephen Rothwell, Saeed Mahameed, and others
for their guidance in these resolutions.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-20 11:53:36 -08:00
Hoang Le 055722716c tipc: fix uninitialized value for broadcast retransmission
When sending broadcast message on high load system, there are a lot of
unnecessary packets restranmission. That issue was caused by missing in
initial criteria for retransmission.

To prevent this happen, just initialize this criteria for retransmission
in next 10 milliseconds.

Fixes: 31c4f4cc32 ("tipc: improve broadcast retransmission algorithm")
Acked-by: Ying Xue <ying.xue@windriver.com>
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>
2018-12-19 11:53:10 -08:00
Tuong Lien cf5f55f7f0 tipc: add trace_events for tipc bearer
The commit adds the new trace_event for TIPC bearer, L2 device event:

trace_tipc_l2_device_event()

Also, it puts the trace at the tipc_l2_device_event() function, then
the device/bearer events and related info can be traced out during
runtime when needed.

Acked-by: Ying Xue <ying.xue@windriver.com>
Tested-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>
2018-12-19 11:49:25 -08:00
Tuong Lien eb18a510b5 tipc: add trace_events for tipc node
The commit adds the new trace_events for TIPC node object:

trace_tipc_node_create()
trace_tipc_node_delete()
trace_tipc_node_lost_contact()
trace_tipc_node_timeout()
trace_tipc_node_link_up()
trace_tipc_node_link_down()
trace_tipc_node_reset_links()
trace_tipc_node_fsm_evt()
trace_tipc_node_check_state()

Also, enables the traces for the following cases:
- When a node is created/deleted;
- When a node contact is lost;
- When a node timer is timed out;
- When a node link is up/down;
- When all node links are reset;
- When node state is changed;
- When a skb comes and node state needs to be checked/updated.

Acked-by: Ying Xue <ying.xue@windriver.com>
Tested-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>
2018-12-19 11:49:24 -08:00
Tuong Lien 01e661ebfb tipc: add trace_events for tipc socket
The commit adds the new trace_events for TIPC socket object:

trace_tipc_sk_create()
trace_tipc_sk_poll()
trace_tipc_sk_sendmsg()
trace_tipc_sk_sendmcast()
trace_tipc_sk_sendstream()
trace_tipc_sk_filter_rcv()
trace_tipc_sk_advance_rx()
trace_tipc_sk_rej_msg()
trace_tipc_sk_drop_msg()
trace_tipc_sk_release()
trace_tipc_sk_shutdown()
trace_tipc_sk_overlimit1()
trace_tipc_sk_overlimit2()

Also, enables the traces for the following cases:
- When user creates a TIPC socket;
- When user calls poll() on TIPC socket;
- When user sends a dgram/mcast/stream message.
- When a message is put into the socket 'sk_receive_queue';
- When a message is released from the socket 'sk_receive_queue';
- When a message is rejected (e.g. due to no port, invalid, etc.);
- When a message is dropped (e.g. due to wrong message type);
- When socket is released;
- When socket is shutdown;
- When socket rcvq's allocation is overlimit (> 90%);
- When socket rcvq + bklq's allocation is overlimit (> 90%);
- When the 'TIPC_ERR_OVERLOAD/2' issue happens;

Note:
a) All the socket traces are designed to be able to trace on a specific
socket by either using the 'event filtering' feature on a known socket
'portid' value or the sysctl file:

/proc/sys/net/tipc/sk_filter

The file determines a 'tuple' for what socket should be traced:

(portid, sock type, name type, name lower, name upper)

where:
+ 'portid' is the socket portid generated at socket creating, can be
found in the trace outputs or the 'tipc socket list' command printouts;
+ 'sock type' is the socket type (1 = SOCK_TREAM, ...);
+ 'name type', 'name lower' and 'name upper' are the service name being
connected to or published by the socket.

Value '0' means 'ANY', the default tuple value is (0, 0, 0, 0, 0) i.e.
the traces happen for every sockets with no filter.

b) The 'tipc_sk_overlimit1/2' event is also a conditional trace_event
which happens when the socket receive queue (and backlog queue) is
about to be overloaded, when the queue allocation is > 90%. Then, when
the trace is enabled, the last skbs leading to the TIPC_ERR_OVERLOAD/2
issue can be traced.

The trace event is designed as an 'upper watermark' notification that
the other traces (e.g. 'tipc_sk_advance_rx' vs 'tipc_sk_filter_rcv') or
actions can be triggerred in the meanwhile to see what is going on with
the socket queue.

In addition, the 'trace_tipc_sk_dump()' is also placed at the
'TIPC_ERR_OVERLOAD/2' case, so the socket and last skb can be dumped
for post-analysis.

Acked-by: Ying Xue <ying.xue@windriver.com>
Tested-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>
2018-12-19 11:49:24 -08:00
Tuong Lien 26574db0c1 tipc: add trace_events for tipc link
The commit adds the new trace_events for TIPC link object:

trace_tipc_link_timeout()
trace_tipc_link_fsm()
trace_tipc_link_reset()
trace_tipc_link_too_silent()
trace_tipc_link_retrans()
trace_tipc_link_bc_ack()
trace_tipc_link_conges()

And the traces for PROTOCOL messages at building and receiving:

trace_tipc_proto_build()
trace_tipc_proto_rcv()

Note:
a) The 'tipc_link_too_silent' event will only happen when the
'silent_intv_cnt' is about to reach the 'abort_limit' value (and the
event is enabled). The benefit for this kind of event is that we can
get an early indication about TIPC link loss issue due to timeout, then
can do some necessary actions for troubleshooting.

For example: To trigger the 'tipc_proto_rcv' when the 'too_silent'
event occurs:

echo 'enable_event:tipc:tipc_proto_rcv' > \
      events/tipc/tipc_link_too_silent/trigger

And disable it when TIPC link is reset:

echo 'disable_event:tipc:tipc_proto_rcv' > \
      events/tipc/tipc_link_reset/trigger

b) The 'tipc_link_retrans' or 'tipc_link_bc_ack' event is useful to
trace TIPC retransmission issues.

In addition, the commit adds the 'trace_tipc_list/link_dump()' at the
'retransmission failure' case. Then, if the issue occurs, the link
'transmq' along with the link data can be dumped for post-analysis.
These dump events should be enabled by default since it will only take
effect when the failure happens.

The same approach is also applied for the faulty case that the
validation of protocol message is failed.

Acked-by: Ying Xue <ying.xue@windriver.com>
Tested-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>
2018-12-19 11:49:24 -08:00
Tuong Lien b4b9771bcb tipc: enable tracepoints in tipc
As for the sake of debugging/tracing, the commit enables tracepoints in
TIPC along with some general trace_events as shown below. It also
defines some 'tipc_*_dump()' functions that allow to dump TIPC object
data whenever needed, that is, for general debug purposes, ie. not just
for the trace_events.

The following trace_events are now available:

- trace_tipc_skb_dump(): allows to trace and dump TIPC msg & skb data,
  e.g. message type, user, droppable, skb truesize, cloned skb, etc.

- trace_tipc_list_dump(): allows to trace and dump any TIPC buffers or
  queues, e.g. TIPC link transmq, socket receive queue, etc.

- trace_tipc_sk_dump(): allows to trace and dump TIPC socket data, e.g.
  sk state, sk type, connection type, rmem_alloc, socket queues, etc.

- trace_tipc_link_dump(): allows to trace and dump TIPC link data, e.g.
  link state, silent_intv_cnt, gap, bc_gap, link queues, etc.

- trace_tipc_node_dump(): allows to trace and dump TIPC node data, e.g.
  node state, active links, capabilities, link entries, etc.

How to use:
Put the trace functions at any places where we want to dump TIPC data
or events.

Note:
a) The dump functions will generate raw data only, that is, to offload
the trace event's processing, it can require a tool or script to parse
the data but this should be simple.

b) The trace_tipc_*_dump() should be reserved for a failure cases only
(e.g. the retransmission failure case) or where we do not expect to
happen too often, then we can consider enabling these events by default
since they will almost not take any effects under normal conditions,
but once the rare condition or failure occurs, we get the dumped data
fully for post-analysis.

For other trace purposes, we can reuse these trace classes as template
but different events.

c) A trace_event is only effective when we enable it. To enable the
TIPC trace_events, echo 1 to 'enable' files in the events/tipc/
directory in the 'debugfs' file system. Normally, they are located at:

/sys/kernel/debug/tracing/events/tipc/

For example:

To enable the tipc_link_dump event:

echo 1 > /sys/kernel/debug/tracing/events/tipc/tipc_link_dump/enable

To enable all the TIPC trace_events:

echo 1 > /sys/kernel/debug/tracing/events/tipc/enable

To collect the trace data:

cat trace

or

cat trace_pipe > /trace.out &

To disable all the TIPC trace_events:

echo 0 > /sys/kernel/debug/tracing/events/tipc/enable

To clear the trace buffer:

echo > trace

d) Like the other trace_events, the feature like 'filter' or 'trigger'
is also usable for the tipc trace_events.
For more details, have a look at:

Documentation/trace/ftrace.txt

MAINTAINERS | add two new files 'trace.h' & 'trace.c' in tipc

Acked-by: Ying Xue <ying.xue@windriver.com>
Tested-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>
2018-12-19 11:49:24 -08:00
Zhenbo Gao 5679ee784c tipc: handle broadcast NAME_DISTRIBUTOR packet when receiving it
NAME_DISTRIBUTOR messages are transmitted through unicast link on TIPC
2.0, by contrast, the messages are delivered through broadcast link on
TIPC 1.7. But at present, NAME_DISTRIBUTOR messages received by
broadcast link cannot be handled in tipc_rcv() until an unicast message
arrives, which may lead to a significant delay to update name table.

To avoid this delay, we will also deal with broadcast NAME_DISTRIBUTOR
message on broadcast receive path.

Signed-off-by: Zhenbo Gao <zhenbo.gao@windriver.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-18 21:50:48 -08:00
Cong Wang 3c6306d440 tipc: check group dests after tipc_wait_for_cond()
Similar to commit 143ece654f ("tipc: check tsk->group in tipc_wait_for_cond()")
we have to reload grp->dests too after we re-take the sock lock.
This means we need to move the dsts check after tipc_wait_for_cond()
too.

Fixes: 75da2163db ("tipc: introduce communication groups")
Reported-and-tested-by: syzbot+99f20222fc5018d2b97a@syzkaller.appspotmail.com
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-18 15:44:23 -08:00
Cong Wang 143ece654f tipc: check tsk->group in tipc_wait_for_cond()
tipc_wait_for_cond() drops socket lock before going to sleep,
but tsk->group could be freed right after that release_sock().
So we have to re-check and reload tsk->group after it wakes up.

After this patch, tipc_wait_for_cond() returns -ERESTARTSYS when
tsk->group is NULL, instead of continuing with the assumption of
a non-NULL tsk->group.

(It looks like 'dsts' should be re-checked and reloaded too, but
it is a different bug.)

Similar for tipc_send_group_unicast() and tipc_send_group_anycast().

Reported-by: syzbot+10a9db47c3a0e13eb31c@syzkaller.appspotmail.com
Fixes: b7d4263551 ("tipc: introduce flow control for group broadcast messages")
Fixes: ee106d7f94 ("tipc: introduce group anycast messaging")
Fixes: 27bd9ec027 ("tipc: introduce group unicast messaging")
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-14 15:48:49 -08:00
Cong Wang fb83ed496b tipc: compare remote and local protocols in tipc_udp_enable()
When TIPC_NLA_UDP_REMOTE is an IPv6 mcast address but
TIPC_NLA_UDP_LOCAL is an IPv4 address, a NULL-ptr deref is triggered
as the UDP tunnel sock is initialized to IPv4 or IPv6 sock merely
based on the protocol in local address.

We should just error out when the remote address and local address
have different protocols.

Reported-by: syzbot+eb4da3a20fad2e52555d@syzkaller.appspotmail.com
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-14 13:28:03 -08:00
Cong Wang acb4a33e98 tipc: fix a double kfree_skb()
tipc_udp_xmit() drops the packet on error, there is no
need to drop it again.

Fixes: ef20cd4dd1 ("tipc: introduce UDP replicast")
Reported-and-tested-by: syzbot+eae585ba2cc2752d3704@syzkaller.appspotmail.com
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-14 13:23:44 -08:00
Cong Wang 15ef70e286 tipc: use lock_sock() in tipc_sk_reinit()
lock_sock() must be used in process context to be race-free with
other lock_sock() callers, for example, tipc_release(). Otherwise
using the spinlock directly can't serialize a parallel tipc_release().

As it is blocking, we have to hold the sock refcnt before
rhashtable_walk_stop() and release it after rhashtable_walk_start().

Fixes: 07f6c4bc04 ("tipc: convert tipc reference table to use generic rhashtable")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Ying Xue <ying.xue@windriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-14 13:16:33 -08:00
Hoang Le f5d6c3e5a3 tipc: fix node keep alive interval calculation
When setting LINK tolerance, node timer interval will be calculated
base on the LINK with lowest tolerance.

But when calculated, the old node timer interval only updated if current
setting value (tolerance/4) less than old ones regardless of number of
links as well as links' lowest tolerance value.

This caused to two cases missing if tolerance changed as following:
Case 1:
1.1/ There is one link (L1) available in the system
1.2/ Set L1's tolerance from 1500ms => lower (i.e 500ms)
1.3/ Then, fallback to default (1500ms) or higher (i.e 2000ms)

Expected:
    node timer interval is 1500/4=375ms after 1.3

Result:
node timer interval will not being updated after changing tolerance at 1.3
since its value 1500/4=375ms is not less than 500/4=125ms at 1.2.

Case 2:
2.1/ There are two links (L1, L2) available in the system
2.2/ L1 and L2 tolerance value are 2000ms as initial
2.3/ Set L2's tolerance from 2000ms => lower 1500ms
2.4/ Disable link L2 (bring down its bearer)

Expected:
    node timer interval is 2000ms/4=500ms after 2.4

Result:
node timer interval will not being updated after disabling L2 since
its value 2000ms/4=500ms is still not less than 1500/4=375ms at 2.3
although L2 is already not available in the system.

To fix this, we start the node interval calculation by initializing it to
a value larger than any conceivable calculated value. This way, the link
with the lowest tolerance will always determine the calculated value.

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>
2018-12-05 20:52:31 -08:00
David S. Miller e561bb29b6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Trivial conflict in net/core/filter.c, a locally computed
'sdif' is now an argument to the function.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-28 22:10:54 -08:00
Jon Maloy ec835f8912 tipc: fix lockdep warning during node delete
We see the following lockdep warning:

[ 2284.078521] ======================================================
[ 2284.078604] WARNING: possible circular locking dependency detected
[ 2284.078604] 4.19.0+ #42 Tainted: G            E
[ 2284.078604] ------------------------------------------------------
[ 2284.078604] rmmod/254 is trying to acquire lock:
[ 2284.078604] 00000000acd94e28 ((&n->timer)#2){+.-.}, at: del_timer_sync+0x5/0xa0
[ 2284.078604]
[ 2284.078604] but task is already holding lock:
[ 2284.078604] 00000000f997afc0 (&(&tn->node_list_lock)->rlock){+.-.}, at: tipc_node_stop+0xac/0x190 [tipc]
[ 2284.078604]
[ 2284.078604] which lock already depends on the new lock.
[ 2284.078604]
[ 2284.078604]
[ 2284.078604] the existing dependency chain (in reverse order) is:
[ 2284.078604]
[ 2284.078604] -> #1 (&(&tn->node_list_lock)->rlock){+.-.}:
[ 2284.078604]        tipc_node_timeout+0x20a/0x330 [tipc]
[ 2284.078604]        call_timer_fn+0xa1/0x280
[ 2284.078604]        run_timer_softirq+0x1f2/0x4d0
[ 2284.078604]        __do_softirq+0xfc/0x413
[ 2284.078604]        irq_exit+0xb5/0xc0
[ 2284.078604]        smp_apic_timer_interrupt+0xac/0x210
[ 2284.078604]        apic_timer_interrupt+0xf/0x20
[ 2284.078604]        default_idle+0x1c/0x140
[ 2284.078604]        do_idle+0x1bc/0x280
[ 2284.078604]        cpu_startup_entry+0x19/0x20
[ 2284.078604]        start_secondary+0x187/0x1c0
[ 2284.078604]        secondary_startup_64+0xa4/0xb0
[ 2284.078604]
[ 2284.078604] -> #0 ((&n->timer)#2){+.-.}:
[ 2284.078604]        del_timer_sync+0x34/0xa0
[ 2284.078604]        tipc_node_delete+0x1a/0x40 [tipc]
[ 2284.078604]        tipc_node_stop+0xcb/0x190 [tipc]
[ 2284.078604]        tipc_net_stop+0x154/0x170 [tipc]
[ 2284.078604]        tipc_exit_net+0x16/0x30 [tipc]
[ 2284.078604]        ops_exit_list.isra.8+0x36/0x70
[ 2284.078604]        unregister_pernet_operations+0x87/0xd0
[ 2284.078604]        unregister_pernet_subsys+0x1d/0x30
[ 2284.078604]        tipc_exit+0x11/0x6f2 [tipc]
[ 2284.078604]        __x64_sys_delete_module+0x1df/0x240
[ 2284.078604]        do_syscall_64+0x66/0x460
[ 2284.078604]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[ 2284.078604]
[ 2284.078604] other info that might help us debug this:
[ 2284.078604]
[ 2284.078604]  Possible unsafe locking scenario:
[ 2284.078604]
[ 2284.078604]        CPU0                    CPU1
[ 2284.078604]        ----                    ----
[ 2284.078604]   lock(&(&tn->node_list_lock)->rlock);
[ 2284.078604]                                lock((&n->timer)#2);
[ 2284.078604]                                lock(&(&tn->node_list_lock)->rlock);
[ 2284.078604]   lock((&n->timer)#2);
[ 2284.078604]
[ 2284.078604]  *** DEADLOCK ***
[ 2284.078604]
[ 2284.078604] 3 locks held by rmmod/254:
[ 2284.078604]  #0: 000000003368be9b (pernet_ops_rwsem){+.+.}, at: unregister_pernet_subsys+0x15/0x30
[ 2284.078604]  #1: 0000000046ed9c86 (rtnl_mutex){+.+.}, at: tipc_net_stop+0x144/0x170 [tipc]
[ 2284.078604]  #2: 00000000f997afc0 (&(&tn->node_list_lock)->rlock){+.-.}, at: tipc_node_stop+0xac/0x19
[...}

The reason is that the node timer handler sometimes needs to delete a
node which has been disconnected for too long. To do this, it grabs
the lock 'node_list_lock', which may at the same time be held by the
generic node cleanup function, tipc_node_stop(), during module removal.
Since the latter is calling del_timer_sync() inside the same lock, we
have a potential deadlock.

We fix this letting the timer cleanup function use spin_trylock()
instead of just spin_lock(), and when it fails to grab the lock it
just returns so that the timer handler can terminate its execution.
This is safe to do, since tipc_node_stop() anyway is about to
delete both the timer and the node instance.

Fixes: 6a939f365b ("tipc: Auto removal of peer down node instance")
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-27 16:30:39 -08:00
David S. Miller f2be6d710d Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-11-19 10:55:00 -08:00
Jon Maloy 1c1274a569 tipc: don't assume linear buffer when reading ancillary data
The code for reading ancillary data from a received buffer is assuming
the buffer is linear. To make this assumption true we have to linearize
the buffer before message data is read.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-17 22:08:02 -08:00
Jon Maloy adba75be0d tipc: fix lockdep warning when reinitilaizing sockets
We get the following warning:

[   47.926140] 32-bit node address hash set to 2010a0a
[   47.927202]
[   47.927433] ================================
[   47.928050] WARNING: inconsistent lock state
[   47.928661] 4.19.0+ #37 Tainted: G            E
[   47.929346] --------------------------------
[   47.929954] inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
[   47.930116] swapper/3/0 [HC0[0]:SC1[3]:HE1:SE0] takes:
[   47.930116] 00000000af8bc31e (&(&ht->lock)->rlock){+.?.}, at: rhashtable_walk_enter+0x36/0xb0
[   47.930116] {SOFTIRQ-ON-W} state was registered at:
[   47.930116]   _raw_spin_lock+0x29/0x60
[   47.930116]   rht_deferred_worker+0x556/0x810
[   47.930116]   process_one_work+0x1f5/0x540
[   47.930116]   worker_thread+0x64/0x3e0
[   47.930116]   kthread+0x112/0x150
[   47.930116]   ret_from_fork+0x3a/0x50
[   47.930116] irq event stamp: 14044
[   47.930116] hardirqs last  enabled at (14044): [<ffffffff9a07fbba>] __local_bh_enable_ip+0x7a/0xf0
[   47.938117] hardirqs last disabled at (14043): [<ffffffff9a07fb81>] __local_bh_enable_ip+0x41/0xf0
[   47.938117] softirqs last  enabled at (14028): [<ffffffff9a0803ee>] irq_enter+0x5e/0x60
[   47.938117] softirqs last disabled at (14029): [<ffffffff9a0804a5>] irq_exit+0xb5/0xc0
[   47.938117]
[   47.938117] other info that might help us debug this:
[   47.938117]  Possible unsafe locking scenario:
[   47.938117]
[   47.938117]        CPU0
[   47.938117]        ----
[   47.938117]   lock(&(&ht->lock)->rlock);
[   47.938117]   <Interrupt>
[   47.938117]     lock(&(&ht->lock)->rlock);
[   47.938117]
[   47.938117]  *** DEADLOCK ***
[   47.938117]
[   47.938117] 2 locks held by swapper/3/0:
[   47.938117]  #0: 0000000062c64f90 ((&d->timer)){+.-.}, at: call_timer_fn+0x5/0x280
[   47.938117]  #1: 00000000ee39619c (&(&d->lock)->rlock){+.-.}, at: tipc_disc_timeout+0xc8/0x540 [tipc]
[   47.938117]
[   47.938117] stack backtrace:
[   47.938117] CPU: 3 PID: 0 Comm: swapper/3 Tainted: G            E     4.19.0+ #37
[   47.938117] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   47.938117] Call Trace:
[   47.938117]  <IRQ>
[   47.938117]  dump_stack+0x5e/0x8b
[   47.938117]  print_usage_bug+0x1ed/0x1ff
[   47.938117]  mark_lock+0x5b5/0x630
[   47.938117]  __lock_acquire+0x4c0/0x18f0
[   47.938117]  ? lock_acquire+0xa6/0x180
[   47.938117]  lock_acquire+0xa6/0x180
[   47.938117]  ? rhashtable_walk_enter+0x36/0xb0
[   47.938117]  _raw_spin_lock+0x29/0x60
[   47.938117]  ? rhashtable_walk_enter+0x36/0xb0
[   47.938117]  rhashtable_walk_enter+0x36/0xb0
[   47.938117]  tipc_sk_reinit+0xb0/0x410 [tipc]
[   47.938117]  ? mark_held_locks+0x6f/0x90
[   47.938117]  ? __local_bh_enable_ip+0x7a/0xf0
[   47.938117]  ? lockdep_hardirqs_on+0x20/0x1a0
[   47.938117]  tipc_net_finalize+0xbf/0x180 [tipc]
[   47.938117]  tipc_disc_timeout+0x509/0x540 [tipc]
[   47.938117]  ? call_timer_fn+0x5/0x280
[   47.938117]  ? tipc_disc_msg_xmit.isra.19+0xa0/0xa0 [tipc]
[   47.938117]  ? tipc_disc_msg_xmit.isra.19+0xa0/0xa0 [tipc]
[   47.938117]  call_timer_fn+0xa1/0x280
[   47.938117]  ? tipc_disc_msg_xmit.isra.19+0xa0/0xa0 [tipc]
[   47.938117]  run_timer_softirq+0x1f2/0x4d0
[   47.938117]  __do_softirq+0xfc/0x413
[   47.938117]  irq_exit+0xb5/0xc0
[   47.938117]  smp_apic_timer_interrupt+0xac/0x210
[   47.938117]  apic_timer_interrupt+0xf/0x20
[   47.938117]  </IRQ>
[   47.938117] RIP: 0010:default_idle+0x1c/0x140
[   47.938117] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 41 54 55 53 65 8b 2d d8 2b 74 65 0f 1f 44 00 00 e8 c6 2c 8b ff fb f4 <65> 8b 2d c5 2b 74 65 0f 1f 44 00 00 5b 5d 41 5c c3 65 8b 05 b4 2b
[   47.938117] RSP: 0018:ffffaf6ac0207ec8 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
[   47.938117] RAX: ffff8f5b3735e200 RBX: 0000000000000003 RCX: 0000000000000001
[   47.938117] RDX: 0000000000000001 RSI: 0000000000000001 RDI: ffff8f5b3735e200
[   47.938117] RBP: 0000000000000003 R08: 0000000000000001 R09: 0000000000000000
[   47.938117] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
[   47.938117] R13: 0000000000000000 R14: ffff8f5b3735e200 R15: ffff8f5b3735e200
[   47.938117]  ? default_idle+0x1a/0x140
[   47.938117]  do_idle+0x1bc/0x280
[   47.938117]  cpu_startup_entry+0x19/0x20
[   47.938117]  start_secondary+0x187/0x1c0
[   47.938117]  secondary_startup_64+0xa4/0xb0

The reason seems to be that tipc_net_finalize()->tipc_sk_reinit() is
calling the function rhashtable_walk_enter() within a timer interrupt.
We fix this by executing tipc_net_finalize() in work queue context.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-17 22:01:31 -08:00
David S. Miller 2b9b7502df Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-11-11 17:57:54 -08:00
Jon Maloy 7ab412d33b tipc: fix link re-establish failure
When a link failure is detected locally, the link is reset, the flag
link->in_session is set to false, and a RESET_MSG with the 'stopping'
bit set is sent to the peer.

The purpose of this bit is to inform the peer that this endpoint just
is going down, and that the peer should handle the reception of this
particular RESET message as a local failure. This forces the peer to
accept another RESET or ACTIVATE message from this endpoint before it
can re-establish the link. This again is necessary to ensure that
link session numbers are properly exchanged before the link comes up
again.

If a failure is detected locally at the same time at the peer endpoint
this will do the same, which is also a correct behavior.

However, when receiving such messages, the endpoints will not
distinguish between 'stopping' RESETs and ordinary ones when it comes
to updating session numbers. Both endpoints will copy the received
session number and set their 'in_session' flags to true at the
reception, while they are still expecting another RESET from the
peer before they can go ahead and re-establish. This is contradictory,
since, after applying the validation check referred to below, the
'in_session' flag will cause rejection of all such messages, and the
link will never come up again.

We now fix this by not only handling received RESET/STOPPING messages
as a local failure, but also by omitting to set a new session number
and the 'in_session' flag in such cases.

Fixes: 7ea817f4e8 ("tipc: check session number before accepting link protocol messages")
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-11 10:03:38 -08:00
LUU Duc Canh 31c4f4cc32 tipc: improve broadcast retransmission algorithm
Currently, the broadcast retransmission algorithm is using the
'prev_retr' field in struct tipc_link to time stamp the latest broadcast
retransmission occasion. This helps to restrict retransmission of
individual broadcast packets to max once per 10 milliseconds, even
though all other criteria for retransmission are met.

We now move this time stamp to the control block of each individual
packet, and remove other limiting criteria. This simplifies the
retransmission algorithm, and eliminates any risk of logical errors
in selecting which packets can be retransmitted.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: LUU Duc Canh <canh.d.luu@dektech.com.au>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-11 09:57:46 -08:00
Linus Torvalds 9931a07d51 Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull AFS updates from Al Viro:
 "AFS series, with some iov_iter bits included"

* 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
  missing bits of "iov_iter: Separate type from direction and use accessor functions"
  afs: Probe multiple fileservers simultaneously
  afs: Fix callback handling
  afs: Eliminate the address pointer from the address list cursor
  afs: Allow dumping of server cursor on operation failure
  afs: Implement YFS support in the fs client
  afs: Expand data structure fields to support YFS
  afs: Get the target vnode in afs_rmdir() and get a callback on it
  afs: Calc callback expiry in op reply delivery
  afs: Fix FS.FetchStatus delivery from updating wrong vnode
  afs: Implement the YFS cache manager service
  afs: Remove callback details from afs_callback_break struct
  afs: Commit the status on a new file/dir/symlink
  afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS
  afs: Don't invoke the server to read data beyond EOF
  afs: Add a couple of tracepoints to log I/O errors
  afs: Handle EIO from delivery function
  afs: Fix TTL on VL server and address lists
  afs: Implement VL server rotation
  afs: Improve FS server rotation error handling
  ...
2018-11-01 19:58:52 -07:00
David Howells aa563d7bca iov_iter: Separate type from direction and use accessor functions
In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.

Signed-off-by: David Howells <dhowells@redhat.com>
2018-10-24 00:41:07 +01:00
Karsten Graul 89ab066d42 Revert "net: simplify sock_poll_wait"
This reverts commit dd979b4df8.

This broke tcp_poll for SMC fallback: An AF_SMC socket establishes an
internal TCP socket for the initial handshake with the remote peer.
Whenever the SMC connection can not be established this TCP socket is
used as a fallback. All socket operations on the SMC socket are then
forwarded to the TCP socket. In case of poll, the file->private_data
pointer references the SMC socket because the TCP socket has no file
assigned. This causes tcp_poll to wait on the wrong socket.

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-23 10:57:06 -07:00
Jon Maloy 988f3f1603 tipc: eliminate message disordering during binding table update
We have seen the following race scenario:
1) named_distribute() builds a "bulk" message, containing a PUBLISH
   item for a certain publication. This is based on the contents of
   the binding tables's 'cluster_scope' list.
2) tipc_named_withdraw() removes the same publication from the list,
   bulds a WITHDRAW message and distributes it to all cluster nodes.
3) tipc_named_node_up(), which was calling named_distribute(), sends
   out the bulk message built under 1)
4) The WITHDRAW message arrives at the just detected node, finds
   no corresponding publication, and is dropped.
5) The PUBLISH item arrives at the same node, is added to its binding
   table, and remains there forever.

This arrival disordering was earlier taken care of by the backlog queue,
originally added for a different purpose, which was removed in the
commit referred to below, but we now need a different solution.
In this commit, we replace the rcu lock protecting the 'cluster_scope'
list with a regular RW lock which comprises even the sending of the
bulk message. This both guarantees both the list integrity and the
message sending order. We will later add a commit which cleans up
this code further.

Note that this commit needs recently added commit d3092b2efc ("tipc:
fix unsafe rcu locking when accessing publication list") to apply
cleanly.

Fixes: 37922ea4a3 ("tipc: permit overlapping service ranges in name table")
Reported-by: Tuong Lien Tong <tuong.t.lien@dektech.com.au>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-22 19:29:12 -07:00
Guoqing Jiang 29e270fc32 tipc: use destination length for copy string
Got below warning with gcc 8.2 compiler.

net/tipc/topsrv.c: In function ‘tipc_topsrv_start’:
net/tipc/topsrv.c:660:2: warning: ‘strncpy’ specified bound depends on the length of the source argument [-Wstringop-overflow=]
  strncpy(srv->name, name, strlen(name) + 1);
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
net/tipc/topsrv.c:660:27: note: length computed here
  strncpy(srv->name, name, strlen(name) + 1);
                           ^~~~~~~~~~~~
So change it to correct length and use strscpy.

Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-22 19:25:32 -07:00
David S. Miller 2e2d6f0342 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
net/sched/cls_api.c has overlapping changes to a call to
nlmsg_parse(), one (from 'net') added rtm_tca_policy instead of NULL
to the 5th argument, and another (from 'net-next') added cb->extack
instead of NULL to the 6th argument.

net/ipv4/ipmr_base.c is a case of a bug fix in 'net' being done to
code which moved (to mr_table_dump)) in 'net-next'.  Thanks to David
Ahern for the heads up.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-19 11:03:06 -07:00
Jon Maloy b06f9d9f1a tipc: fix info leak from kernel tipc_event
We initialize a struct tipc_event allocated on the kernel stack to
zero to avert info leak to user space.

Reported-by: syzbot+057458894bc8cada4dee@syzkaller.appspotmail.com
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-18 16:49:53 -07:00
Tung Nguyen d3092b2efc tipc: fix unsafe rcu locking when accessing publication list
The binding table's 'cluster_scope' list is rcu protected to handle
races between threads changing the list and those traversing the list at
the same moment. We have now found that the function named_distribute()
uses the regular list_for_each() macro to traverse the said list.
Likewise, the function tipc_named_withdraw() is removing items from the
same list using the regular list_del() call. When these two functions
execute in parallel we see occasional crashes.

This commit fixes this by adding the missing _rcu() suffixes.

Signed-off-by: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-15 22:33:27 -07:00
Jon Maloy 4af00f4cc1 tipc: initialize broadcast link stale counter correctly
In the commit referred to below we added link tolerance as an additional
criteria for declaring broadcast transmission "stale" and resetting the
unicast links to the affected node.

Unfortunately, this 'improvement' introduced two bugs, which each and
one alone cause only limited problems, but combined lead to seemingly
stochastic unicast link resets, depending on the amount of broadcast
traffic transmitted.

The first issue, a missing initialization of the 'tolerance' field of
the receiver broadcast link, was recently fixed by commit 047491ea33
("tipc: set link tolerance correctly in broadcast link").

Ths second issue, where we omit to reset the 'stale_cnt' field of
the same link after a 'stale' period is over, leads to this counter
accumulating over time, and in the absence of the 'tolerance' criteria
leads to the above described symptoms. This commit adds the missing
initialization.

Fixes: a4dc70d46c ("tipc: extend link reset criteria for stale packet retransmission")
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-15 22:03:34 -07:00
Hoang Le acad76a5f6 tipc: support binding to specific ip address when activating UDP bearer
INADDR_ANY is hard-coded when activating UDP bearer. So, we could not
bind to a specific IP address even with replicast mode using - given
remote ip address instead of using multicast ip address.

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

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

after:
$netstat -plu
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address           Foreign Address
udp        0      0 **10.0.0.2:6118**           0.0.0.0:*

Acked-by: Ying Xue <ying.xue@windriver.com>
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>
2018-10-15 21:56:56 -07:00
David S. Miller d864991b22 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts were easy to resolve using immediate context mostly,
except the cls_u32.c one where I simply too the entire HEAD
chunk.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-12 21:38:46 -07:00
Ying Xue a1f8dd34e6 tipc: eliminate possible recursive locking detected by LOCKDEP
When booting kernel with LOCKDEP option, below warning info was found:

WARNING: possible recursive locking detected
4.19.0-rc7+ #14 Not tainted
--------------------------------------------
swapper/0/1 is trying to acquire lock:
00000000dcfc0fc8 (&(&list->lock)->rlock#4){+...}, at: spin_lock_bh
include/linux/spinlock.h:334 [inline]
00000000dcfc0fc8 (&(&list->lock)->rlock#4){+...}, at:
tipc_link_reset+0x125/0xdf0 net/tipc/link.c:850

but task is already holding lock:
00000000cbb9b036 (&(&list->lock)->rlock#4){+...}, at: spin_lock_bh
include/linux/spinlock.h:334 [inline]
00000000cbb9b036 (&(&list->lock)->rlock#4){+...}, at:
tipc_link_reset+0xfa/0xdf0 net/tipc/link.c:849

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

       CPU0
       ----
  lock(&(&list->lock)->rlock#4);
  lock(&(&list->lock)->rlock#4);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by swapper/0/1:
 #0: 00000000f7539d34 (pernet_ops_rwsem){+.+.}, at:
register_pernet_subsys+0x19/0x40 net/core/net_namespace.c:1051
 #1: 00000000cbb9b036 (&(&list->lock)->rlock#4){+...}, at:
spin_lock_bh include/linux/spinlock.h:334 [inline]
 #1: 00000000cbb9b036 (&(&list->lock)->rlock#4){+...}, at:
tipc_link_reset+0xfa/0xdf0 net/tipc/link.c:849

stack backtrace:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc7+ #14
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1af/0x295 lib/dump_stack.c:113
 print_deadlock_bug kernel/locking/lockdep.c:1759 [inline]
 check_deadlock kernel/locking/lockdep.c:1803 [inline]
 validate_chain kernel/locking/lockdep.c:2399 [inline]
 __lock_acquire+0xf1e/0x3c60 kernel/locking/lockdep.c:3411
 lock_acquire+0x1db/0x520 kernel/locking/lockdep.c:3900
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
 _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:168
 spin_lock_bh include/linux/spinlock.h:334 [inline]
 tipc_link_reset+0x125/0xdf0 net/tipc/link.c:850
 tipc_link_bc_create+0xb5/0x1f0 net/tipc/link.c:526
 tipc_bcast_init+0x59b/0xab0 net/tipc/bcast.c:521
 tipc_init_net+0x472/0x610 net/tipc/core.c:82
 ops_init+0xf7/0x520 net/core/net_namespace.c:129
 __register_pernet_operations net/core/net_namespace.c:940 [inline]
 register_pernet_operations+0x453/0xac0 net/core/net_namespace.c:1011
 register_pernet_subsys+0x28/0x40 net/core/net_namespace.c:1052
 tipc_init+0x83/0x104 net/tipc/core.c:140
 do_one_initcall+0x109/0x70a init/main.c:885
 do_initcall_level init/main.c:953 [inline]
 do_initcalls init/main.c:961 [inline]
 do_basic_setup init/main.c:979 [inline]
 kernel_init_freeable+0x4bd/0x57f init/main.c:1144
 kernel_init+0x13/0x180 init/main.c:1063
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413

The reason why the noise above was complained by LOCKDEP is because we
nested to hold l->wakeupq.lock and l->inputq->lock in tipc_link_reset
function. In fact it's unnecessary to move skb buffer from l->wakeupq
queue to l->inputq queue while holding the two locks at the same time.
Instead, we can move skb buffers in l->wakeupq queue to a temporary
list first and then move the buffers of the temporary list to l->inputq
queue, which is also safe for us.

Fixes: 3f32d0be6c ("tipc: lock wakeup & inputq at tipc_link_reset()")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-11 10:23:48 -07:00
Parthasarathy Bhuvaragan e7eb058238 tipc: queue socket protocol error messages into socket receive buffer
In tipc_sk_filter_rcv(), when we detect protocol messages with error we
call tipc_sk_conn_proto_rcv() and let it reset the connection and notify
the socket by calling sk->sk_state_change().

However, tipc_sk_filter_rcv() may have been called from the function
tipc_backlog_rcv(), in which case the socket lock is held and the socket
already awake. This means that the sk_state_change() call is ignored and
the error notification lost. Now the receive queue will remain empty and
the socket sleeps forever.

In this commit, we convert the protocol message into a connection abort
message and enqueue it into the socket's receive queue. By this addition
to the above state change we cover all conditions.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-10 22:56:07 -07:00
Jon Maloy 047491ea33 tipc: set link tolerance correctly in broadcast link
In the patch referred to below we added link tolerance as an additional
criteria for declaring broadcast transmission "stale" and resetting the
affected links.

However, the 'tolerance' field of the broadcast link is never set, and
remains at zero. This renders the whole commit without the intended
improving effect, but luckily also with no negative effect.

In this commit we add the missing initialization.

Fixes: a4dc70d46c ("tipc: extend link reset criteria for stale packet retransmission")
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-10 22:56:07 -07:00
David S. Miller 6f41617bf2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor conflict in net/core/rtnetlink.c, David Ahern's bug fix in 'net'
overlapped the renaming of a netlink attribute in net-next.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-03 21:00:17 -07:00
LUU Duc Canh d949cfedbc tipc: ignore STATE_MSG on wrong link session
The initial session number when a link is created is based on a random
value, taken from struct tipc_net->random. It is then incremented for
each link reset to avoid mixing protocol messages from different link
sessions.

However, when a bearer is reset all its links are deleted, and will
later be re-created using the same random value as the first time.
This means that if the link never went down between creation and
deletion we will still sometimes have two subsequent sessions with
the same session number. In virtual environments with potentially
long transmission times this has turned out to be a real problem.

We now fix this by randomizing the session number each time a link
is created.

With a session number size of 16 bits this gives a risk of session
collision of 1/64k. To reduce this further, we also introduce a sanity
check on the very first STATE message arriving at a link. If this has
an acknowledge value differing from 0, which is logically impossible,
we ignore the message. The final risk for session collision is hence
reduced to 1/4G, which should be sufficient.

Signed-off-by: LUU Duc Canh <canh.d.luu@dektech.com.au>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-01 22:35:30 -07:00
LUU Duc Canh c140eb166d tipc: fix failover problem
We see the following scenario:
1) Link endpoint B on node 1 discovers that its peer endpoint is gone.
   Since there is a second working link, failover procedure is started.
2) Link endpoint A on node 1 sends a FAILOVER message to peer endpoint
   A on node 2. The node item 1->2 goes to state FAILINGOVER.
3) Linke endpoint A/2 receives the failover, and is supposed to take
   down its parallell link endpoint B/2, while producing a FAILOVER
   message to send back to A/1.
4) However, B/2 has already been deleted, so no FAILOVER message can
   created.
5) Node 1->2 remains in state FAILINGOVER forever, refusing to receive
   any messages that can bring B/1 up again. We are left with a non-
   redundant link between node 1 and 2.

We fix this with letting endpoint A/2 build a dummy FAILOVER message
to send to back to A/1, so that the situation can be resolved.

Signed-off-by: LUU Duc Canh <canh.d.luu@dektech.com.au>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-29 11:45:14 -07:00
Tung Nguyen 6787927475 tipc: buffer overflow handling in listener socket
Default socket receive buffer size for a listener socket is 2Mb. For
each arriving empty SYN, the linux kernel allocates a 768 bytes buffer.
This means that a listener socket can serve maximum 2700 simultaneous
empty connection setup requests before it hits a receive buffer
overflow, and much fewer if the SYN is carrying any significant
amount of data.

When this happens the setup request is rejected, and the client
receives an ECONNREFUSED error.

This commit mitigates this problem by letting the client socket try to
retransmit the SYN message multiple times when it sees it rejected with
the code TIPC_ERR_OVERLOAD. Retransmission is done at random intervals
in the range of [100 ms, setup_timeout / 4], as many times as there is
room for within the setup timeout limit.

Signed-off-by: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-29 11:24:22 -07:00
Jon Maloy 25b9221b95 tipc: add SYN bit to connection setup messages
Messages intended for intitating a connection are currently
indistinguishable from regular datagram messages. The TIPC
protocol specification defines bit 17 in word 0 as a SYN bit
to allow sanity check of such messages in the listening socket,
but this has so far never been implemented.

We do that in this commit.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-29 11:24:22 -07:00
Jon Maloy 39fdc9c71f tipc: refactor function tipc_sk_filter_connect()
We refactor the function tipc_sk_filter_connect(), both to make it
more readable and as a preparation for the next commit.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-29 11:24:22 -07:00
Jon Maloy afe8792fec tipc: refactor function tipc_sk_timeout()
We refactor this function as a preparation for the coming commits in
the same series.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-29 11:24:22 -07:00
Jon Maloy 5cbdbd1a1f tipc: refactor function tipc_msg_reverse()
The function tipc_msg_reverse() is reversing the header of a message
while reusing the original buffer. We have seen at several occasions
that this may have unfortunate side effects when the buffer to be
reversed is a clone.

In one of the following commits we will again need to reverse cloned
buffers, so this is the right time to permanently eliminate this
problem. In this commit we let the said function always consume the
original buffer and replace it with a new one when applicable.

Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-29 11:24:22 -07:00