Commit Graph

1426 Commits

Author SHA1 Message Date
Jon Maloy b39e465e56 tipc: some cleanups in the file discover.c
To facilitate the coming changes in the neighbor discovery functionality
we make some renaming and refactoring of that code. The functional changes
in this commit are trivial, e.g., that we move the message sending call in
tipc_disc_timeout() outside the spinlock protected region.

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>
2018-03-23 13:12:17 -04:00
Jon Maloy cb30a63384 tipc: refactor function tipc_enable_bearer()
As a preparation for the next commits we try to reduce the footprint of
the function tipc_enable_bearer(), while hopefully making is simpler to
follow.

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>
2018-03-23 13:12:17 -04:00
GhantaKrishnamurthy MohanKrishna 872619d8cf tipc: step sk->sk_drops when rcv buffer is full
Currently when tipc is unable to queue a received message on a
socket, the message is rejected back to the sender with error
TIPC_ERR_OVERLOAD. However, the application on this socket
has no knowledge about these discards.

In this commit, we try to step the sk_drops counter when tipc
is unable to queue a received message. Export sk_drops
using tipc socket diagnostics.

Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: GhantaKrishnamurthy MohanKrishna <mohan.krishna.ghanta.krishnamurthy@ericsson.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-22 14:43:37 -04:00
GhantaKrishnamurthy MohanKrishna c30b70deb5 tipc: implement socket diagnostics for AF_TIPC
This commit adds socket diagnostics capability for AF_TIPC in netlink
family NETLINK_SOCK_DIAG in a new kernel module (diag.ko).

The following are key design considerations:
- config TIPC_DIAG has default y, like INET_DIAG.
- only requests with flag NLM_F_DUMP is supported (dump all).
- tipc_sock_diag_req message is introduced to send filter parameters.
- the response attributes are of TLV, some nested.

To avoid exposing data structures between diag and tipc modules and
avoid code duplication, the following additions are required:
- export tipc_nl_sk_walk function to reuse socket iterator.
- export tipc_sk_fill_sock_diag to fill the tipc diag attributes.
- create a sock_diag response message in __tipc_add_sock_diag defined
  in diag.c and use the above exported tipc_sk_fill_sock_diag
  to fill response.

Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: GhantaKrishnamurthy MohanKrishna <mohan.krishna.ghanta.krishnamurthy@ericsson.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-22 14:43:35 -04:00
GhantaKrishnamurthy MohanKrishna dfde331e75 tipc: modify socket iterator for sock_diag
The current socket iterator function tipc_nl_sk_dump, handles socket
locks and calls __tipc_nl_add_sk for each socket.
To reuse this logic in sock_diag implementation, we do minor
modifications to make these functions generic as described below.

In this commit, we add a two new functions __tipc_nl_sk_walk,
__tipc_nl_add_sk_info and modify tipc_nl_sk_dump, __tipc_nl_add_sk
accordingly.

In __tipc_nl_sk_walk we:
1. acquire and release socket locks
2. for each socket, execute the specified callback function

In __tipc_nl_add_sk we:
- Move the netlink attribute insertion to __tipc_nl_add_sk_info.

tipc_nl_sk_dump calls tipc_nl_sk_walk with __tipc_nl_add_sk as argument.

sock_diag will use these generic functions in a later commit.

There is no functional change in this commit.
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: GhantaKrishnamurthy MohanKrishna <mohan.krishna.ghanta.krishnamurthy@ericsson.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-22 14:43:29 -04:00
Jon Maloy e50e73e107 tipc: some name changes
We rename some lists and fields in struct publication both to make
the naming more consistent and to better reflect their roles. We
also update the descriptions of those lists.

node_list -> local_publ
cluster_list -> all_publ
pport_list -> binding_sock
ref -> port

There are no functional changes 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>
2018-03-17 17:11:46 -04:00
Jon Maloy 935439cc48 tipc: merge two lists in struct publication
The size of struct publication can be reduced further. Membership in
lists 'nodesub_list' and 'local_list' is mutually exlusive, in that
remote publications use the former and local publications the latter.
We replace the two lists with one single, named 'binding_node' which
reflects what it really is.

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>
2018-03-17 17:11:46 -04:00
Jon Maloy ba765ec637 tipc: remove zone_list member in struct publication
As a further consequence of the previous commits, we can also remove
the member 'zone_list 'in struct name_info and struct publication.
Instead, we now let the member cluster_list take over the role a
container of all publications of a given <type,lower, upper>.
We also remove the counters for the size of those lists, since
they don't serve any purpose.

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>
2018-03-17 17:11:46 -04:00
Jon Maloy 64a52b26d5 tipc: remove zone publication list in name table
As a consequence of the previous commit we nan now eliminate zone scope
related lists in the name table. We start with name_table::publ_list[3],
which can now be replaced with two lists, one for node scope publications
and one for cluster scope publications.

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>
2018-03-17 17:11:46 -04:00
Jon Maloy 928df1880e tipc: obsolete TIPC_ZONE_SCOPE
Publications for TIPC_CLUSTER_SCOPE and TIPC_ZONE_SCOPE are in all
aspects handled the same way, both on the publishing node and on the
receiving nodes.

Despite previous ambitions to the contrary, this is never going to change,
so we take the conseqeunce of this and obsolete TIPC_ZONE_SCOPE and related
macros/functions. Whenever a user is doing a bind() or a sendmsg() attempt
using ZONE_SCOPE we translate this internally to CLUSTER_SCOPE, while we
remain compatible with users and remote nodes still using ZONE_SCOPE.

Furthermore, the non-formalized scope value 0 has always been permitted
for use during lookup, with the same meaning as ZONE_SCOPE/CLUSTER_SCOPE.
We now permit it even as binding scope, but for compatibility reasons we
choose to not change the value of TIPC_CLUSTER_SCOPE.

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>
2018-03-17 17:11:46 -04:00
Kirill Tkhai afbbc374ab net: Convert tipc_net_ops
TIPC looks concentrated in itself, and other pernet_operations
seem not touching its entities.

tipc_net_ops look pernet-divided, and they should be safe to
be executed in parallel for several net the same time.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-13 11:24:56 -04:00
Gustavo A. R. Silva c9efb15a99 tipc: bcast: use true and false for boolean values
Assign true or false to boolean variables instead of an integer value.

This issue was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-07 12:18:00 -05:00
David S. Miller 0f3e9c97eb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
All of the conflicts were cases of overlapping changes.

In net/core/devlink.c, we have to make care that the
resouce size_params have become a struct member rather
than a pointer to such an object.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-06 01:20:46 -05:00
Jon Maloy 1b22bcad7e tipc: correct initial value for group congestion flag
In commit 60c2530696 ("tipc: fix race between poll() and
setsockopt()") we introduced a pointer from struct tipc_group to the
'group_is_connected' flag in struct tipc_sock, so that this field can
be checked without dereferencing the group pointer of the latter struct.

The initial value for this flag is correctly set to 'false' when a
group is created, but we miss the case when no group is created at
all, in which case the initial value should be 'true'. This has the
effect that SOCK_RDM/DGRAM sockets sending datagrams never receive
POLLOUT if they request so.

This commit corrects this bug.

Fixes: 60c2530696 ("tipc: fix race between poll() and setsockopt()")
Reported-by: Hoang Le <hoang.h.le@dektek.com.au>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-27 11:46:03 -05:00
David S. Miller f5c0c6f429 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-02-19 18:46:11 -05:00
Paolo Abeni 26736a08ee tipc: don't call sock_release() in atomic context
syzbot reported a scheduling while atomic issue at netns
destruction time:

BUG: sleeping function called from invalid context at net/core/sock.c:2769
in_atomic(): 1, irqs_disabled(): 0, pid: 85, name: kworker/u4:3
5 locks held by kworker/u4:3/85:
  #0:  ((wq_completion)"%s""netns"){+.+.}, at: [<00000000c9792deb>]
process_one_work+0xaaf/0x1af0 kernel/workqueue.c:2084
  #1:  (net_cleanup_work){+.+.}, at: [<00000000adc12e2a>]
process_one_work+0xb01/0x1af0 kernel/workqueue.c:2088
  #2:  (net_sem){++++}, at: [<000000009ccb5669>] cleanup_net+0x23f/0xd20
net/core/net_namespace.c:494
  #3:  (net_mutex){+.+.}, at: [<00000000a92767d9>] cleanup_net+0xa7d/0xd20
net/core/net_namespace.c:496
  #4:  (&(&srv->idr_lock)->rlock){+...}, at: [<000000001343e568>]
spin_lock_bh include/linux/spinlock.h:315 [inline]
  #4:  (&(&srv->idr_lock)->rlock){+...}, at: [<000000001343e568>]
tipc_topsrv_stop+0x231/0x610 net/tipc/topsrv.c:685
CPU: 0 PID: 85 Comm: kworker/u4:3 Not tainted 4.16.0-rc1+ #230
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
  __dump_stack lib/dump_stack.c:17 [inline]
  dump_stack+0x194/0x257 lib/dump_stack.c:53
  ___might_sleep+0x2b2/0x470 kernel/sched/core.c:6128
  __might_sleep+0x95/0x190 kernel/sched/core.c:6081
  lock_sock_nested+0x37/0x110 net/core/sock.c:2769
  lock_sock include/net/sock.h:1463 [inline]
  tipc_release+0x103/0xff0 net/tipc/socket.c:572
  sock_release+0x8d/0x1e0 net/socket.c:594
  tipc_topsrv_stop+0x3c0/0x610 net/tipc/topsrv.c:696
  tipc_exit_net+0x15/0x40 net/tipc/core.c:96
  ops_exit_list.isra.6+0xae/0x150 net/core/net_namespace.c:148
  cleanup_net+0x6ba/0xd20 net/core/net_namespace.c:529
  process_one_work+0xbbf/0x1af0 kernel/workqueue.c:2113
  worker_thread+0x223/0x1990 kernel/workqueue.c:2247
  kthread+0x33c/0x400 kernel/kthread.c:238
  ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:429

This is caused by tipc_topsrv_stop() releasing the listener socket
with the idr lock held. This changeset addresses the issue moving
the release operation outside such lock.

Reported-and-tested-by: syzbot+749d9d87c294c00ca856@syzkaller.appspotmail.com
Fixes: 0ef897be12 ("tipc: separate topology server listener socket from subcsriber sockets")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by:  ///jon
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-19 14:38:50 -05:00
Jon Maloy 96c252bf1c tipc: fix bug on error path in tipc_topsrv_kern_subscr()
In commit cc1ea9ffadf7 ("tipc: eliminate struct tipc_subscriber") we
re-introduced an old bug on the error path in the function
tipc_topsrv_kern_subscr(). We now re-introduce the correction too.

Reported-by: syzbot+f62e0f2a0ef578703946@syzkaller.appspotmail.com
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-19 14:38:08 -05:00
Jon Maloy 026321c6d0 tipc: rename tipc_server to tipc_topsrv
We rename struct tipc_server to struct tipc_topsrv. This reflect its now
specialized role as topology server. Accoringly, we change or add function
prefixes to make it clearer which functionality those belong to.

There are no functional changes 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>
2018-02-16 15:26:34 -05:00
Jon Maloy 0ef897be12 tipc: separate topology server listener socket from subcsriber sockets
We move the listener socket to struct tipc_server and give it its own
work item. This makes it easier to follow the code, and entails some
simplifications in the reception code in subscriber sockets.

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>
2018-02-16 15:26:34 -05:00
Jon Maloy 5c45ab24ac tipc: make struct tipc_server private for server.c
In order to narrow the interface and dependencies between the topology
server and the subscription/binding table functionality we move struct
tipc_server inside the file server.c. This requires some code
adaptations in other files, but those are mostly minor.

The most important change is that we have to move the start/stop
functions for the topology server to server.c, where they logically
belong anyway.

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>
2018-02-16 15:26:34 -05:00
Jon Maloy da0a75e86a tipc: some prefix changes
Since we now have removed struct tipc_subscriber from the code, and
only struct tipc_subscription remains, there is no longer need for long
and awkward prefixes to distinguish between their pertaining functions.

We now change all tipc_subscrp_* prefixes to tipc_sub_*. This is
a purely cosmetic change.

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>
2018-02-16 15:26:34 -05:00
Jon Maloy 242e82cc95 tipc: collapse subscription creation functions
After the previous changes it becomes logical to collapse the two-level
creation of subscription instances into one. We do that here.

We also rename the creation and deletion functions for more consistency.

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>
2018-02-16 15:26:34 -05:00
Jon Maloy 8985ecc7c1 tipc: simplify endianness handling in topology subscriber
Because of the requirement for total distribution transparency, users
send subscriptions and receive topology events in their own host format.
It is up to the topology server to determine this format and do the
correct conversions to and from its own host format when needed.

Until now, this has been handled in a rather non-transparent way inside
the topology server and subscriber code, leading to unnecessary
complexity when creating subscriptions and issuing events.

We now improve this situation by adding two new macros, tipc_sub_read()
and tipc_evt_write(). Both those functions calculate the need for
conversion internally before performing their respective operations.
Hence, all handling of such conversions become transparent to the rest
of the code.

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>
2018-02-16 15:26:33 -05:00
Jon Maloy 414574a0af tipc: simplify interaction between subscription and topology connection
The message transmission and reception in the topology server is more
generic than is currently necessary. By basing the funtionality on the
fact that we only send items of type struct tipc_event and always
receive items of struct tipc_subcr we can make several simplifications,
and also get rid of some unnecessary dynamic memory allocations.

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>
2018-02-16 15:26:33 -05:00
Jon Maloy df79d040dc tipc: eliminate struct tipc_subscriber
It is unnecessary to keep two structures, struct tipc_conn and struct
tipc_subscriber, with a one-to-one relationship and still with different
life cycles. The fact that the two often run in different contexts, and
still may access each other via direct pointers constitutes an additional
hazard, something we have experienced at several occasions, and still
see happening.

We have identified at least two remaining problems that are easier to
fix if we simplify the topology server data structure somewhat.

- When there is a race between a subscription up/down event and a
  timeout event, it is fully possible that the former might be delivered
  after the latter, leading to confusion for the receiver.

- The function tipc_subcrp_timeout() is executing in interrupt context,
  while the following call chain is at least theoretically possible:
  tipc_subscrp_timeout()
    tipc_subscrp_send_event()
      tipc_conn_sendmsg()
        conn_put()
          tipc_conn_kref_release()
            sock_release(sock)

I.e., we end up calling a function that might try to sleep in
interrupt context. To eliminate this, we need to ensure that the
tipc_conn structure and the socket, as well as the subscription
instances, only are deleted in work queue context, i.e., after the
timeout event really has been sent out.

We now remove this unnecessary complexity, by merging data and
functionality of the subscriber structure into struct tipc_conn
and the associated file server.c. We thereafter add a spinlock and
a new 'inactive' state to the subscription structure. Using those,
both problems described above can be easily solved.

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>
2018-02-16 15:26:33 -05:00
Jon Maloy c901d26d4a tipc: remove unnecessary function pointers
Interaction between the functionality in server.c and subscr.c is
done via function pointers installed in struct server. This makes
the code harder to follow, and doesn't serve any obvious purpose.

Here, we replace the function pointers with direct function calls.

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>
2018-02-16 15:26:33 -05:00
Jon Maloy 27469b7352 tipc: remove redundant code in topology server
The socket handling in the topology server is unnecessarily generic.
It is prepared to handle both SOCK_RDM, SOCK_DGRAM and SOCK_STREAM
type sockets, as well as the only socket type which is really used,
SOCK_SEQPACKET.

We now remove this redundant code to make the code more readable.

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>
2018-02-16 15:26:33 -05:00
Jon Maloy 37c64cf63b tipc: apply bearer link tolerance on running links
Currently, the default link tolerance set in struct tipc_bearer only
has effect on links going up after that moment. I.e., a user has to
reset all the node's links across that bearer to have the new value
applied. This is too limiting and disturbing on a running cluster to
be useful.

We now change this so that also already existing links are updated
dynamically, without any need for a reset, when the bearer value is
changed. We leverage the already existing per-link functionality
for this to achieve the wanted effect.

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>
2018-02-14 15:22:24 -05:00
Ying Xue ed4ffdfec2 tipc: Fix missing RTNL lock protection during setting link properties
Currently when user changes link properties, TIPC first checks if
user's command message contains media name or bearer name through
tipc_media_find() or tipc_bearer_find() which is protected by RTNL
lock. But when tipc_nl_compat_link_set() conducts the checking with
the two functions, it doesn't hold RTNL lock at all, as a result,
the following complaints were reported:

audit: type=1400 audit(1514679888.244:9): avc:  denied  { write } for
pid=3194 comm="syzkaller021477" path="socket:[11143]" dev="sockfs"
ino=11143 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023
tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023
tclass=netlink_generic_socket permissive=1
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>

=============================
WARNING: suspicious RCU usage
4.15.0-rc5+ #152 Not tainted
-----------------------------
net/tipc/bearer.c:177 suspicious rcu_dereference_protected() usage!

other info that might help us debug this:

rcu_scheduler_active = 2, debug_locks = 1
2 locks held by syzkaller021477/3194:
  #0:  (cb_lock){++++}, at: [<00000000d20133ea>] genl_rcv+0x19/0x40
net/netlink/genetlink.c:634
  #1:  (genl_mutex){+.+.}, at: [<00000000fcc5d1bc>] genl_lock
net/netlink/genetlink.c:33 [inline]
  #1:  (genl_mutex){+.+.}, at: [<00000000fcc5d1bc>] genl_rcv_msg+0x115/0x140
net/netlink/genetlink.c:622

stack backtrace:
CPU: 1 PID: 3194 Comm: syzkaller021477 Not tainted 4.15.0-rc5+ #152
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+0x194/0x257 lib/dump_stack.c:53
  lockdep_rcu_suspicious+0x123/0x170 kernel/locking/lockdep.c:4585
  tipc_bearer_find+0x2b4/0x3b0 net/tipc/bearer.c:177
  tipc_nl_compat_link_set+0x329/0x9f0 net/tipc/netlink_compat.c:729
  __tipc_nl_compat_doit net/tipc/netlink_compat.c:288 [inline]
  tipc_nl_compat_doit+0x15b/0x660 net/tipc/netlink_compat.c:335
  tipc_nl_compat_handle net/tipc/netlink_compat.c:1119 [inline]
  tipc_nl_compat_recv+0x112f/0x18f0 net/tipc/netlink_compat.c:1201
  genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:599
  genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:624
  netlink_rcv_skb+0x21e/0x460 net/netlink/af_netlink.c:2408
  genl_rcv+0x28/0x40 net/netlink/genetlink.c:635
  netlink_unicast_kernel net/netlink/af_netlink.c:1275 [inline]
  netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1301
  netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1864
  sock_sendmsg_nosec net/socket.c:636 [inline]
  sock_sendmsg+0xca/0x110 net/socket.c:646
  sock_write_iter+0x31a/0x5d0 net/socket.c:915
  call_write_iter include/linux/fs.h:1772 [inline]
  new_sync_write fs/read_write.c:469 [inline]
  __vfs_write+0x684/0x970 fs/read_write.c:482
  vfs_write+0x189/0x510 fs/read_write.c:544
  SYSC_write fs/read_write.c:589 [inline]
  SyS_write+0xef/0x220 fs/read_write.c:581
  do_syscall_32_irqs_on arch/x86/entry/common.c:327 [inline]
  do_fast_syscall_32+0x3ee/0xf9d arch/x86/entry/common.c:389
  entry_SYSENTER_compat+0x54/0x63 arch/x86/entry/entry_64_compat.S:129

In order to correct the mistake, __tipc_nl_compat_doit() has been
protected by RTNL lock, which means the whole operation of setting
bearer/media properties is under RTNL protection.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Reported-by: syzbot <syzbot+6345fd433db009b29413@syzkaller.appspotmail.com>

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-14 14:46:33 -05:00
Ying Xue 5631f65dec tipc: Introduce __tipc_nl_net_set
Introduce __tipc_nl_net_set() which doesn't hold RTNL lock.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-14 14:46:33 -05:00
Ying Xue 07ffb22357 tipc: Introduce __tipc_nl_media_set
Introduce __tipc_nl_media_set() which doesn't hold RTNL lock.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-14 14:46:32 -05:00
Ying Xue 93532bb1d4 tipc: Introduce __tipc_nl_bearer_set
Introduce __tipc_nl_bearer_set() which doesn't holding RTNL lock.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-14 14:46:32 -05:00
Ying Xue 45cf7edfbc tipc: Introduce __tipc_nl_bearer_enable
Introduce __tipc_nl_bearer_enable() which doesn't hold RTNL lock.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-14 14:46:32 -05:00
Ying Xue d59d8b77ab tipc: Introduce __tipc_nl_bearer_disable
Introduce __tipc_nl_bearer_disable() which doesn't hold RTNL lock.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-14 14:46:32 -05:00
Ying Xue e5d1a1eec0 tipc: Refactor __tipc_nl_compat_doit
As preparation for adding RTNL to make (*cmd->transcode)() and
(*cmd->transcode)() constantly protected by RTNL lock, we move out of
memory allocations existing between them as many as possible so that
the time of holding RTNL can be minimized in __tipc_nl_compat_doit().

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-14 14:46:32 -05:00
Denys Vlasenko 9b2c45d479 net: make getname() functions return length rather than use int* parameter
Changes since v1:
Added changes in these files:
    drivers/infiniband/hw/usnic/usnic_transport.c
    drivers/staging/lustre/lnet/lnet/lib-socket.c
    drivers/target/iscsi/iscsi_target_login.c
    drivers/vhost/net.c
    fs/dlm/lowcomms.c
    fs/ocfs2/cluster/tcp.c
    security/tomoyo/network.c

Before:
All these functions either return a negative error indicator,
or store length of sockaddr into "int *socklen" parameter
and return zero on success.

"int *socklen" parameter is awkward. For example, if caller does not
care, it still needs to provide on-stack storage for the value
it does not need.

None of the many FOO_getname() functions of various protocols
ever used old value of *socklen. They always just overwrite it.

This change drops this parameter, and makes all these functions, on success,
return length of sockaddr. It's always >= 0 and can be differentiated
from an error.

Tests in callers are changed from "if (err)" to "if (err < 0)", where needed.

rpc_sockname() lost "int buflen" parameter, since its only use was
to be passed to kernel_getsockname() as &buflen and subsequently
not used in any way.

Userspace API is not changed.

    text    data     bss      dec     hex filename
30108430 2633624  873672 33615726 200ef6e vmlinux.before.o
30108109 2633612  873672 33615393 200ee21 vmlinux.o

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: David S. Miller <davem@davemloft.net>
CC: linux-kernel@vger.kernel.org
CC: netdev@vger.kernel.org
CC: linux-bluetooth@vger.kernel.org
CC: linux-decnet-user@lists.sourceforge.net
CC: linux-wireless@vger.kernel.org
CC: linux-rdma@vger.kernel.org
CC: linux-sctp@vger.kernel.org
CC: linux-nfs@vger.kernel.org
CC: linux-x25@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-12 14:15:04 -05:00
Linus Torvalds a9a08845e9 vfs: do bulk POLL* -> EPOLL* replacement
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:

    for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
        L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
        for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
    done

with de-mangling cleanups yet to come.

NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do.  But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.

The next patch from Al will sort out the final differences, and we
should be all done.

Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-02-11 14:34:03 -08:00
Hoang Le 55b3280d1e tipc: fix skb truesize/datasize ratio control
In commit d618d09a68 ("tipc: enforce valid ratio between skb truesize
and contents") we introduced a test for ensuring that the condition
truesize/datasize <= 4 is true for a received buffer. Unfortunately this
test has two problems.

- Because of the integer arithmetics the test
  if (skb->truesize / buf_roundup_len(skb) > 4) will miss all
  ratios [4 < ratio < 5], which was not the intention.
- The buffer returned by skb_copy() inherits skb->truesize of the
  original buffer, which doesn't help the situation at all.

In this commit, we change the ratio condition and replace skb_copy()
with a call to skb_copy_expand() to finally get this right.

Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-02-08 15:30:40 -05:00
Linus Torvalds b2fe5fa686 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:

 1) Significantly shrink the core networking routing structures. Result
    of http://vger.kernel.org/~davem/seoul2017_netdev_keynote.pdf

 2) Add netdevsim driver for testing various offloads, from Jakub
    Kicinski.

 3) Support cross-chip FDB operations in DSA, from Vivien Didelot.

 4) Add a 2nd listener hash table for TCP, similar to what was done for
    UDP. From Martin KaFai Lau.

 5) Add eBPF based queue selection to tun, from Jason Wang.

 6) Lockless qdisc support, from John Fastabend.

 7) SCTP stream interleave support, from Xin Long.

 8) Smoother TCP receive autotuning, from Eric Dumazet.

 9) Lots of erspan tunneling enhancements, from William Tu.

10) Add true function call support to BPF, from Alexei Starovoitov.

11) Add explicit support for GRO HW offloading, from Michael Chan.

12) Support extack generation in more netlink subsystems. From Alexander
    Aring, Quentin Monnet, and Jakub Kicinski.

13) Add 1000BaseX, flow control, and EEE support to mvneta driver. From
    Russell King.

14) Add flow table abstraction to netfilter, from Pablo Neira Ayuso.

15) Many improvements and simplifications to the NFP driver bpf JIT,
    from Jakub Kicinski.

16) Support for ipv6 non-equal cost multipath routing, from Ido
    Schimmel.

17) Add resource abstration to devlink, from Arkadi Sharshevsky.

18) Packet scheduler classifier shared filter block support, from Jiri
    Pirko.

19) Avoid locking in act_csum, from Davide Caratti.

20) devinet_ioctl() simplifications from Al viro.

21) More TCP bpf improvements from Lawrence Brakmo.

22) Add support for onlink ipv6 route flag, similar to ipv4, from David
    Ahern.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1925 commits)
  tls: Add support for encryption using async offload accelerator
  ip6mr: fix stale iterator
  net/sched: kconfig: Remove blank help texts
  openvswitch: meter: Use 64-bit arithmetic instead of 32-bit
  tcp_nv: fix potential integer overflow in tcpnv_acked
  r8169: fix RTL8168EP take too long to complete driver initialization.
  qmi_wwan: Add support for Quectel EP06
  rtnetlink: enable IFLA_IF_NETNSID for RTM_NEWLINK
  ipmr: Fix ptrdiff_t print formatting
  ibmvnic: Wait for device response when changing MAC
  qlcnic: fix deadlock bug
  tcp: release sk_frag.page in tcp_disconnect
  ipv4: Get the address of interface correctly.
  net_sched: gen_estimator: fix lockdep splat
  net: macb: Handle HRESP error
  net/mlx5e: IPoIB, Fix copy-paste bug in flow steering refactoring
  ipv6: addrconf: break critical section in addrconf_verify_rtnl()
  ipv6: change route cache aging logic
  i40e/i40evf: Update DESC_NEEDED value to reflect larger value
  bnxt_en: cleanup DIM work on device shutdown
  ...
2018-01-31 14:31:10 -08:00
Linus Torvalds 1ed2d76e02 Merge branch 'work.sock_recvmsg' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull kern_recvmsg reduction from Al Viro:
 "kernel_recvmsg() is a set_fs()-using wrapper for sock_recvmsg(). In
  all but one case that is not needed - use of ITER_KVEC for ->msg_iter
  takes care of the data and does not care about set_fs(). The only
  exception is svc_udp_recvfrom() where we want cmsg to be store into
  kernel object; everything else can just use sock_recvmsg() and be done
  with that.

  A followup converting svc_udp_recvfrom() away from set_fs() (and
  killing kernel_recvmsg() off) is *NOT* in here - I'd like to hear what
  netdev folks think of the approach proposed in that followup)"

* 'work.sock_recvmsg' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  tipc: switch to sock_recvmsg()
  smc: switch to sock_recvmsg()
  ipvs: switch to sock_recvmsg()
  mISDN: switch to sock_recvmsg()
  drbd: switch to sock_recvmsg()
  lustre lnet_sock_read(): switch to sock_recvmsg()
  cfs2: switch to sock_recvmsg()
  ncpfs: switch to sock_recvmsg()
  dlm: switch to sock_recvmsg()
  svc_recvfrom(): switch to sock_recvmsg()
2018-01-30 18:59:03 -08:00
Linus Torvalds 168fe32a07 Merge branch 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull poll annotations from Al Viro:
 "This introduces a __bitwise type for POLL### bitmap, and propagates
  the annotations through the tree. Most of that stuff is as simple as
  'make ->poll() instances return __poll_t and do the same to local
  variables used to hold the future return value'.

  Some of the obvious brainos found in process are fixed (e.g. POLLIN
  misspelled as POLL_IN). At that point the amount of sparse warnings is
  low and most of them are for genuine bugs - e.g. ->poll() instance
  deciding to return -EINVAL instead of a bitmap. I hadn't touched those
  in this series - it's large enough as it is.

  Another problem it has caught was eventpoll() ABI mess; select.c and
  eventpoll.c assumed that corresponding POLL### and EPOLL### were
  equal. That's true for some, but not all of them - EPOLL### are
  arch-independent, but POLL### are not.

  The last commit in this series separates userland POLL### values from
  the (now arch-independent) kernel-side ones, converting between them
  in the few places where they are copied to/from userland. AFAICS, this
  is the least disruptive fix preserving poll(2) ABI and making epoll()
  work on all architectures.

  As it is, it's simply broken on sparc - try to give it EPOLLWRNORM and
  it will trigger only on what would've triggered EPOLLWRBAND on other
  architectures. EPOLLWRBAND and EPOLLRDHUP, OTOH, are never triggered
  at all on sparc. With this patch they should work consistently on all
  architectures"

* 'misc.poll' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (37 commits)
  make kernel-side POLL... arch-independent
  eventpoll: no need to mask the result of epi_item_poll() again
  eventpoll: constify struct epoll_event pointers
  debugging printk in sg_poll() uses %x to print POLL... bitmap
  annotate poll(2) guts
  9p: untangle ->poll() mess
  ->si_band gets POLL... bitmap stored into a user-visible long field
  ring_buffer_poll_wait() return value used as return value of ->poll()
  the rest of drivers/*: annotate ->poll() instances
  media: annotate ->poll() instances
  fs: annotate ->poll() instances
  ipc, kernel, mm: annotate ->poll() instances
  net: annotate ->poll() instances
  apparmor: annotate ->poll() instances
  tomoyo: annotate ->poll() instances
  sound: annotate ->poll() instances
  acpi: annotate ->poll() instances
  crypto: annotate ->poll() instances
  block: annotate ->poll() instances
  x86: annotate ->poll() instances
  ...
2018-01-30 17:58:07 -08:00
Jon Maloy 60c2530696 tipc: fix race between poll() and setsockopt()
Letting tipc_poll() dereference a socket's pointer to struct tipc_group
entails a race risk, as the group item may be deleted in a concurrent
tipc_sk_join() or tipc_sk_leave() thread.

We now move the 'open' flag in struct tipc_group to struct tipc_sock,
and let the former retain only a pointer to the moved field. This will
eliminate the race risk.

Reported-by: syzbot+799dafde0286795858ac@syzkaller.appspotmail.com
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-19 15:12:21 -05:00
David S. Miller c02b3741eb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Overlapping changes all over.

The mini-qdisc bits were a little bit tricky, however.

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-17 00:10:42 -05:00
Jon Maloy e88f2be832 tipc: fix race condition at topology server receive
We have identified a race condition during reception of socket
events and messages in the topology server.

- The function tipc_close_conn() is releasing the corresponding
  struct tipc_subscriber instance without considering that there
  may still be items in the receive work queue. When those are
  scheduled, in the function tipc_receive_from_work(), they are
  using the subscriber pointer stored in struct tipc_conn, without
  first checking if this is valid or not. This will sometimes
  lead to crashes, as the next call of tipc_conn_recvmsg() will
  access the now deleted item.
  We fix this by making the usage of this pointer conditional on
  whether the connection is active or not. I.e., we check the condition
  test_bit(CF_CONNECTED) before making the call tipc_conn_recvmsg().

- Since the two functions may be running on different cores, the
  condition test described above is not enough. tipc_close_conn()
  may come in between and delete the subscriber item after the condition
  test is done, but before tipc_conn_recv_msg() is finished. This
  happens less frequently than the problem described above, but leads
  to the same symptoms.

  We fix this by using the existing sk_callback_lock for mutual
  exclusion in the two functions. In addition, we have to move
  a call to tipc_conn_terminate() outside the mentioned lock to
  avoid deadlock.

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>
2018-01-16 14:42:41 -05:00
Jon Maloy e9a034456a tipc: fix bug during lookup of multicast destination nodes
In commit 232d07b74a ("tipc: improve groupcast scope handling") we
inadvertently broke non-group multicast transmission when changing the
parameter 'domain' to 'scope' in the function
tipc_nametbl_lookup_dst_nodes(). We missed to make the corresponding
change in the calling function, with the result that the lookup always
fails.

A closer anaysis reveals that this parameter is not needed at all.
Non-group multicast is hard coded to use CLUSTER_SCOPE, and in the
current implementation this will be delivered to all matching
destinations except those which are published with NODE_SCOPE on other
nodes. Since such publications never will be visible on the sending node
anyway, it makes no sense to discriminate by scope at all.

We now remove this parameter altogether.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-15 14:27:13 -05:00
Cong Wang 59b36613e8 tipc: fix a memory leak in tipc_nl_node_get_link()
When tipc_node_find_by_name() fails, the nlmsg is not
freed.

While on it, switch to a goto label to properly
free it.

Fixes: be9c086715c ("tipc: narrow down exposure of struct tipc_node")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Ying Xue <ying.xue@windriver.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>
2018-01-15 13:45:50 -05:00
Jon Maloy febafc8455 tipc: fix a potental access after delete in tipc_sk_join()
In commit d12d2e12ce "tipc: send out join messages as soon as new
member is discovered") we added a call to the function tipc_group_join()
without considering the case that the preceding tipc_sk_publish() might
have failed, and the group item already deleted.

We fix this by returning from tipc_sk_join() directly after the
failed tipc_sk_publish.

Reported-by: syzbot+e3eeae78ea88b8d6d858@syzkaller.appspotmail.com
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-15 13:43:51 -05:00
Jon Maloy eb929a91b2 tipc: improve poll() for group member socket
The current criteria for returning POLLOUT from a group member socket is
too simplistic. It basically returns POLLOUT as soon as the group has
external destinations, something obviously leading to a lot of spinning
during destination congestion situations. At the same time, the internal
congestion handling is unnecessarily complex.

We now change this as follows.

- We introduce an 'open' flag in  struct tipc_group. This flag is used
  only to help poll() get the setting of POLLOUT right, and *not* for
  congeston handling as such. This means that a user can choose to
  ignore an  EAGAIN for a destination and go on sending messages to
  other destinations in the group if he wants to.

- The flag is set to false every time we return EAGAIN on a send call.

- The flag is set to true every time any member, i.e., not necessarily
  the member that caused EAGAIN, is removed from the small_win list.

- We remove the group member 'usr_pending' flag. The size of the send
  window and presence in the 'small_win' list is sufficient criteria
  for recognizing congestion.

This solution seems to be a reasonable compromise between 'anycast',
which is normally not waiting for POLLOUT for a specific destination,
and the other three send modes, which are.

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>
2018-01-09 12:35:58 -05:00
Jon Maloy 232d07b74a tipc: improve groupcast scope handling
When a member joins a group, it also indicates a binding scope. This
makes it possible to create both node local groups, invisible to other
nodes, as well as cluster global groups, visible everywhere.

In order to avoid that different members end up having permanently
differing views of group size and memberhip, we must inhibit locally
and globally bound members from joining the same group.

We do this by using the binding scope as an additional separator between
groups. I.e., a member must ignore all membership events from sockets
using a different scope than itself, and all lookups for message
destinations must require an exact match between the message's lookup
scope and the potential target's binding scope.

Apart from making it possible to create local groups using the same
identity on different nodes, a side effect of this is that it now also
becomes possible to create a cluster global group with the same identity
across the same nodes, without interfering with the local groups.

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>
2018-01-09 12:35:58 -05:00
Jon Maloy 8348500f80 tipc: add option to suppress PUBLISH events for pre-existing publications
Currently, when a user is subscribing for binding table publications,
he will receive a PUBLISH event for all already existing matching items
in the binding table.

However, a group socket making a subscriptions doesn't need this initial
status update from the binding table, because it has already scanned it
during the join operation. Worse, the multiplicatory effect of issuing
mutual events for dozens or hundreds group members within a short time
frame put a heavy load on the topology server, with the end result that
scale out operations on a big group tend to take much longer than needed.

We now add a new filter option, TIPC_SUB_NO_STATUS, for topology server
subscriptions, so that this initial avalanche of events is suppressed.
This change, along with the previous commit, significantly improves the
range and speed of group scale out operations.

We keep the new option internal for the tipc driver, at least for now.

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>
2018-01-09 12:35:58 -05:00
Jon Maloy d12d2e12ce tipc: send out join messages as soon as new member is discovered
When a socket is joining a group, we look up in the binding table to
find if there are already other members of the group present. This is
used for being able to return EAGAIN instead of EHOSTUNREACH if the
user proceeds directly to a send attempt.

However, the information in the binding table can be used to directly
set the created member in state MBR_PUBLISHED and send a JOIN message
to the peer, instead of waiting for a topology PUBLISH event to do this.
When there are many members in a group, the propagation time for such
events can be significant, and we can save time during the join
operation if we use the initial lookup result fully.

In this commit, we eliminate the member state MBR_DISCOVERED which has
been the result of the initial lookup, and do instead go directly to
MBR_PUBLISHED, which initiates the setup.

After this change, the tipc_member FSM looks as follows:

     +-----------+
---->| PUBLISHED |-----------------------------------------------+
PUB- +-----------+                                 LEAVE/WITHRAW |
LISH       |JOIN                                                 |
           |     +-------------------------------------------+   |
           |     |                            LEAVE/WITHDRAW |   |
           |     |                +------------+             |   |
           |     |   +----------->|  PENDING   |---------+   |   |
           |     |   |msg/maxactv +-+---+------+  LEAVE/ |   |   |
           |     |   |              |   |       WITHDRAW |   |   |
           |     |   |   +----------+   |                |   |   |
           |     |   |   |revert/maxactv|                |   |   |
           |     |   |   V              V                V   V   V
           |   +----------+  msg  +------------+       +-----------+
           +-->|  JOINED  |------>|   ACTIVE   |------>|  LEAVING  |--->
           |   +----------+       +--- -+------+ LEAVE/+-----------+DOWN
           |        A   A               |      WITHDRAW A   A    A   EVT
           |        |   |               |RECLAIM        |   |    |
           |        |   |REMIT          V               |   |    |
           |        |   |== adv   +------------+        |   |    |
           |        |   +---------| RECLAIMING |--------+   |    |
           |        |             +-----+------+  LEAVE/    |    |
           |        |                   |REMIT   WITHDRAW   |    |
           |        |                   |< adv              |    |
           |        |msg/               V            LEAVE/ |    |
           |        |adv==ADV_IDLE+------------+   WITHDRAW |    |
           |        +-------------|  REMITTED  |------------+    |
           |                      +------------+                 |
           |PUBLISH                                              |
JOIN +-----------+                                LEAVE/WITHDRAW |
---->|  JOINING  |-----------------------------------------------+
     +-----------+

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>
2018-01-09 12:35:58 -05:00
Jon Maloy c2b22bcf2e tipc: simplify group LEAVE sequence
After the changes in the previous commit the group LEAVE sequence
can be simplified.

We now let the arrival of a LEAVE message unconditionally issue a group
DOWN event to the user. When a topology WITHDRAW event is received, the
member, if it still there, is set to state LEAVING, but we only issue a
group DOWN event when the link to the peer node is gone, so that no
LEAVE message is to be expected.

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>
2018-01-09 12:35:57 -05:00
Jon Maloy 7ad32bcb78 tipc: create group member event messages when they are needed
In the current implementation, a group socket receiving topology
events about other members just converts the topology event message
into a group event message and stores it until it reaches the right
state to issue it to the user. This complicates the code unnecessarily,
and becomes impractical when we in the coming commits will need to
create and issue membership events independently.

In this commit, we change this so that we just notice the type and
origin of the incoming topology event, and then drop the buffer. Only
when it is time to actually send a group event to the user do we
explicitly create a new message and send it upwards.

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>
2018-01-09 12:35:57 -05:00
Jon Maloy 0233493a5f tipc: adjustment to group member FSM
Analysis reveals that the member state MBR_QURANTINED in reality is
unnecessary, and can be replaced by the state MBR_JOINING at all
occurrencs.

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>
2018-01-09 12:35:57 -05:00
Jon Maloy 4ea5dab541 tipc: let group member stay in JOINED mode if unable to reclaim
We handle a corner case in the function tipc_group_update_rcv_win().
During extreme pessure it might happen that a message receiver has all
its active senders in RECLAIMING or REMITTED mode, meaning that there
is nobody to reclaim advertisements from if an additional sender tries
to go active.

Currently we just set the new sender to ACTIVE anyway, hence at least
theoretically opening up for a receiver queue overflow by exceeding the
MAX_ACTIVE limit. The correct solution to this is to instead add the
member to the pending queue, while letting the oldest member in that
queue revert to JOINED state.

In this commit we refactor the code for handling message arrival from
a JOINED member, both to make it more comprehensible and to cover the
case described above.

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>
2018-01-09 12:35:57 -05:00
Jon Maloy 8d5dee21f6 tipc: a couple of cleanups
- We remove the 'reclaiming' member list in struct tipc_group, since
  it doesn't serve any purpose.

- We simplify the GRP_REMIT_MSG branch of tipc_group_protocol_rcv().

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>
2018-01-09 12:35:57 -05:00
David S. Miller a0ce093180 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-01-09 10:37:00 -05:00
Yang Shi f4803f1b73 net: tipc: remove unused hardirq.h
Preempt counter APIs have been split out, currently, hardirq.h just
includes irq_enter/exit APIs which are not used by TIPC at all.

So, remove the unused hardirq.h.

Signed-off-by: Yang Shi <yang.s@alibaba-inc.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Ying Xue <ying.xue@windriver.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-08 20:59:25 -05:00
Jon Maloy d84d1b3b6b tipc: simplify small window members' sorting algorithm
We simplify the sorting algorithm in tipc_update_member(). We also make
the remaining conditional call to this function unconditional, since the
same condition now is tested for inside the said function.

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>
2018-01-05 13:37:03 -05:00
Jon Maloy 38266ca17c tipc: some clarifying name changes
We rename some functions and variables, to make their purpose clearer.

- tipc_group::congested -> tipc_group::small_win. Members in this list
  are not necessarily (and typically) congested. Instead, they may
  *potentially* be subject to congestion because their send window is
  less than ADV_IDLE, and therefore need to be checked during message
  transmission.

- tipc_group_is_receiver() -> tipc_group_is_sender(). This socket will
  accept messages coming from members fulfilling this condition, i.e.,
  they are senders from this member's viewpoint.

- tipc_group_is_enabled() -> tipc_group_is_receiver(). Members
  fulfilling this condition will accept messages sent from the current
  socket, i.e., they are receivers from its viewpoint.

There are no functional changes 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>
2018-01-05 13:37:03 -05:00
Jon Maloy f9c935db80 tipc: fix problems with multipoint-to-point flow control
In commit 04d7b574b2 ("tipc: add multipoint-to-point flow control") we
introduced a protocol for preventing buffer overflow when many group
members try to simultaneously send messages to the same receiving member.

Stress test of this mechanism has revealed a couple of related bugs:

- When the receiving member receives an advertisement REMIT message from
  one of the senders, it will sometimes prematurely activate a pending
  member and send it the remitted advertisement, although the upper
  limit for active senders has been reached. This leads to accumulation
  of illegal advertisements, and eventually to messages being dropped
  because of receive buffer overflow.

- When the receiving member leaves REMITTED state while a received
  message is being read, we miss to look at the pending queue, to
  activate the oldest pending peer. This leads to some pending senders
  being starved out, and never getting the opportunity to profit from
  the remitted advertisement.

We fix the former in the function tipc_group_proto_rcv() by returning
directly from the function once it becomes clear that the remitting
peer cannot leave REMITTED state at that point.

We fix the latter in the function tipc_group_update_rcv_win() by looking
up and activate the longest pending peer when it becomes clear that the
remitting peer now can leave REMITTED state.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-02 21:52:07 -05:00
David S. Miller 6bb8824732 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
net/ipv6/ip6_gre.c is a case of parallel adds.

include/trace/events/tcp.h is a little bit more tricky.  The removal
of in-trace-macro ifdefs in 'net' paralleled with moving
show_tcp_state_name and friends over to include/trace/events/sock.h
in 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-29 15:42:26 -05:00
Parthasarathy Bhuvaragan 517d7c79bd tipc: fix hanging poll() for stream sockets
In commit 42b531de17 ("tipc: Fix missing connection request
handling"), we replaced unconditional wakeup() with condtional
wakeup for clients with flags POLLIN | POLLRDNORM | POLLRDBAND.

This breaks the applications which do a connect followed by poll
with POLLOUT flag. These applications are not woken when the
connection is ESTABLISHED and hence sleep forever.

In this commit, we fix it by including the POLLOUT event for
sockets in TIPC_CONNECTING state.

Fixes: 42b531de17 ("tipc: Fix missing connection request handling")
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-28 12:15:26 -05:00
Tommi Rantala 642a8439dd tipc: fix tipc_mon_delete() oops in tipc_enable_bearer() error path
Calling tipc_mon_delete() before the monitor has been created will oops.
This can happen in tipc_enable_bearer() error path if tipc_disc_create()
fails.

[   48.589074] BUG: unable to handle kernel paging request at 0000000000001008
[   48.590266] IP: tipc_mon_delete+0xea/0x270 [tipc]
[   48.591223] PGD 1e60c5067 P4D 1e60c5067 PUD 1eb0cf067 PMD 0
[   48.592230] Oops: 0000 [#1] SMP KASAN
[   48.595610] CPU: 5 PID: 1199 Comm: tipc Tainted: G    B            4.15.0-rc4-pc64-dirty #5
[   48.597176] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-2.fc27 04/01/2014
[   48.598489] RIP: 0010:tipc_mon_delete+0xea/0x270 [tipc]
[   48.599347] RSP: 0018:ffff8801d827f668 EFLAGS: 00010282
[   48.600705] RAX: ffff8801ee813f00 RBX: 0000000000000204 RCX: 0000000000000000
[   48.602183] RDX: 1ffffffff1de6a75 RSI: 0000000000000297 RDI: 0000000000000297
[   48.604373] RBP: 0000000000000000 R08: 0000000000000000 R09: fffffbfff1dd1533
[   48.605607] R10: ffffffff8eafbb05 R11: fffffbfff1dd1534 R12: 0000000000000050
[   48.607082] R13: dead000000000200 R14: ffffffff8e73f310 R15: 0000000000001020
[   48.608228] FS:  00007fc686484800(0000) GS:ffff8801f5540000(0000) knlGS:0000000000000000
[   48.610189] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   48.611459] CR2: 0000000000001008 CR3: 00000001dda70002 CR4: 00000000003606e0
[   48.612759] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   48.613831] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   48.615038] Call Trace:
[   48.615635]  tipc_enable_bearer+0x415/0x5e0 [tipc]
[   48.620623]  tipc_nl_bearer_enable+0x1ab/0x200 [tipc]
[   48.625118]  genl_family_rcv_msg+0x36b/0x570
[   48.631233]  genl_rcv_msg+0x5a/0xa0
[   48.631867]  netlink_rcv_skb+0x1cc/0x220
[   48.636373]  genl_rcv+0x24/0x40
[   48.637306]  netlink_unicast+0x29c/0x350
[   48.639664]  netlink_sendmsg+0x439/0x590
[   48.642014]  SYSC_sendto+0x199/0x250
[   48.649912]  do_syscall_64+0xfd/0x2c0
[   48.650651]  entry_SYSCALL64_slow_path+0x25/0x25
[   48.651843] RIP: 0033:0x7fc6859848e3
[   48.652539] RSP: 002b:00007ffd25dff938 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
[   48.654003] RAX: ffffffffffffffda RBX: 00007ffd25dff990 RCX: 00007fc6859848e3
[   48.655303] RDX: 0000000000000054 RSI: 00007ffd25dff990 RDI: 0000000000000003
[   48.656512] RBP: 00007ffd25dff980 R08: 00007fc685c35fc0 R09: 000000000000000c
[   48.657697] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000d13010
[   48.658840] R13: 00007ffd25e009c0 R14: 0000000000000000 R15: 0000000000000000
[   48.662972] RIP: tipc_mon_delete+0xea/0x270 [tipc] RSP: ffff8801d827f668
[   48.664073] CR2: 0000000000001008
[   48.664576] ---[ end trace e811818d54d5ce88 ]---

Acked-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-27 10:55:00 -05:00
Tommi Rantala 19142551b2 tipc: error path leak fixes in tipc_enable_bearer()
Fix memory leak in tipc_enable_bearer() if enable_media() fails, and
cleanup with bearer_disable() if tipc_mon_create() fails.

Acked-by: Ying Xue <ying.xue@windriver.com>
Acked-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-27 10:54:59 -05:00
Jon Maloy 3a33a19bf8 tipc: fix memory leak of group member when peer node is lost
When a group member receives a member WITHDRAW event, this might have
two reasons: either the peer member is leaving the group, or the link
to the member's node has been lost.

In the latter case we need to issue a DOWN event to the user right away,
and let function tipc_group_filter_msg() perform delete of the member
item. However, in this case we miss to change the state of the member
item to MBR_LEAVING, so the member item is not deleted, and we have a
memory leak.

We now separate better between the four sub-cases of a WITHRAW event
and make sure that each case is handled correctly.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-26 13:06:36 -05:00
Jon Maloy 0a3d805c9c tipc: base group replicast ack counter on number of actual receivers
In commit 2f487712b8 ("tipc: guarantee that group broadcast doesn't
bypass group unicast") we introduced a mechanism that requires the first
(replicated) broadcast sent after a unicast to be acknowledged by all
receivers before permitting sending of the next (true) broadcast.

The counter for keeping track of the number of acknowledges to expect
is based on the tipc_group::member_cnt variable. But this misses that
some of the known members may not be ready for reception, and will never
acknowledge the message, either because they haven't fully joined the
group or because they are leaving the group. Such members are identified
by not fulfilling the condition tested for in the function
tipc_group_is_enabled().

We now set the counter for the actual number of acks to receive at the
moment the message is sent, by just counting the number of recipients
satisfying the tipc_group_is_enabled() test.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-26 13:00:04 -05:00
David S. Miller fba961ab29 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Lots of overlapping changes.  Also on the net-next side
the XDP state management is handled more in the generic
layers so undo the 'net' nfp fix which isn't applicable
in net-next.

Include a necessary change by Jakub Kicinski, with log message:

====================
cls_bpf no longer takes care of offload tracking.  Make sure
netdevsim performs necessary checks.  This fixes a warning
caused by TC trying to remove a filter it has not added.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-22 11:16:31 -05:00
Jon Maloy bb25c3855a tipc: remove joining group member from congested list
When we receive a JOIN message from a peer member, the message may
contain an advertised window value ADV_IDLE that permits removing the
member in question from the tipc_group::congested list. However, since
the removal has been made conditional on that the advertised window is
*not* ADV_IDLE, we miss this case. This has the effect that a sender
sometimes may enter a state of permanent, false, broadcast congestion.

We fix this by unconditinally removing the member from the congested
list before calling tipc_member_update(), which might potentially sort
it into the list again.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-20 14:56:48 -05:00
Jon Maloy 3db0960117 tipc: fix list sorting bug in function tipc_group_update_member()
When, during a join operation, or during message transmission, a group
member needs to be added to the group's 'congested' list, we sort it
into the list in ascending order, according to its current advertised
window size. However, we miss the case when the member is already on
that list. This will have the result that the member, after the window
size has been decremented, might be at the wrong position in that list.
This again may have the effect that we during broadcast and multicast
transmissions miss the fact that a destination is not yet ready for
reception, and we end up sending anyway. From this point on, the
behavior during the remaining session is unpredictable, e.g., with
underflowing window sizes.

We now correct this bug by unconditionally removing the member from
the list before (re-)sorting it in.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-19 14:10:03 -05:00
Jon Maloy 3f42f5fe31 tipc: remove leaving group member from all lists
A group member going into state LEAVING should never go back to any
other state before it is finally deleted. However, this might happen
if the socket needs to send out a RECLAIM message during this interval.
Since we forget to remove the leaving member from the group's 'active'
or 'pending' list, the member might be selected for reclaiming, change
state to RECLAIMING, and get stuck in this state instead of being
deleted. This might lead to suppression of the expected 'member down'
event to the receiver.

We fix this by removing the member from all lists, except the RB tree,
at the moment it goes into state LEAVING.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-18 13:16:40 -05:00
Jon Maloy 234833991e tipc: fix lost member events bug
Group messages are not supposed to be returned to sender when the
destination socket disappears. This is done correctly for regular
traffic messages, by setting the 'dest_droppable' bit in the header.
But we forget to do that in group protocol messages. This has the effect
that such messages may sometimes bounce back to the sender, be perceived
as a legitimate peer message, and wreak general havoc for the rest of
the session. In particular, we have seen that a member in state LEAVING
may go back to state RECLAIMED or REMITTED, hence causing suppression
of an otherwise expected 'member down' event to the user.

We fix this by setting the 'dest_droppable' bit even in group protocol
messages.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-18 13:16:40 -05:00
David S. Miller c30abd5e40 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three sets of overlapping changes, two in the packet scheduler
and one in the meson-gxl PHY driver.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-16 22:11:55 -05:00
Jon Maloy c545a945d0 tipc: eliminate potential memory leak
In the function tipc_sk_mcast_rcv() we call refcount_dec(&skb->users)
on received sk_buffers. Since the reference counter might hit zero at
this point, we have a potential memory leak.

We fix this by replacing refcount_dec() with kfree_skb().

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-13 13:44:36 -05:00
Tom Herbert 97a6ec4ac0 rhashtable: Change rhashtable_walk_start to return void
Most callers of rhashtable_walk_start don't care about a resize event
which is indicated by a return value of -EAGAIN. So calls to
rhashtable_walk_start are wrapped wih code to ignore -EAGAIN. Something
like this is common:

       ret = rhashtable_walk_start(rhiter);
       if (ret && ret != -EAGAIN)
               goto out;

Since zero and -EAGAIN are the only possible return values from the
function this check is pointless. The condition never evaluates to true.

This patch changes rhashtable_walk_start to return void. This simplifies
code for the callers that ignore -EAGAIN. For the few cases where the
caller cares about the resize event, particularly where the table can be
walked in mulitple parts for netlink or seq file dump, the function
rhashtable_walk_start_check has been added that returns -EAGAIN on a
resize event.

Signed-off-by: Tom Herbert <tom@quantonium.net>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-11 09:58:38 -05:00
David S. Miller 51e18a453f Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflict was two parallel additions of include files to sch_generic.c,
no biggie.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-09 22:09:55 -05:00
Jon Maloy a7d5f107b4 tipc: fix memory leak in tipc_accept_from_sock()
When the function tipc_accept_from_sock() fails to create an instance of
struct tipc_subscriber it omits to free the already created instance of
struct tipc_conn instance before it returns.

We fix that with this commit.

Reported-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 14:52:41 -05:00
Cong Wang 672ecbe1c9 tipc: fix a null pointer deref on error path
In tipc_topsrv_kern_subscr() when s->tipc_conn_new() fails
we call tipc_close_conn() to clean up, but in this case
calling conn_put() is just enough.

This fixes the folllowing crash:

 kasan: GPF could be caused by NULL-ptr deref or user memory access
 general protection fault: 0000 [#1] SMP KASAN
 Dumping ftrace buffer:
    (ftrace buffer empty)
 Modules linked in:
 CPU: 0 PID: 3085 Comm: syzkaller064164 Not tainted 4.15.0-rc1+ #137
 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 task: 00000000c24413a5 task.stack: 000000005e8160b5
 RIP: 0010:__lock_acquire+0xd55/0x47f0 kernel/locking/lockdep.c:3378
 RSP: 0018:ffff8801cb5474a8 EFLAGS: 00010002
 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 0000000000000004 RSI: 0000000000000000 RDI: ffffffff85ecb400
 RBP: ffff8801cb547830 R08: 0000000000000001 R09: 0000000000000000
 R10: 0000000000000000 R11: ffffffff87489d60 R12: ffff8801cd2980c0
 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000020
 FS:  00000000014ee880(0000) GS:ffff8801db400000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 00007ffee2426e40 CR3: 00000001cb85a000 CR4: 00000000001406f0
 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
 Call Trace:
  lock_acquire+0x1d5/0x580 kernel/locking/lockdep.c:4004
  __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
  _raw_spin_lock_bh+0x31/0x40 kernel/locking/spinlock.c:175
  spin_lock_bh include/linux/spinlock.h:320 [inline]
  tipc_subscrb_subscrp_delete+0x8f/0x470 net/tipc/subscr.c:201
  tipc_subscrb_delete net/tipc/subscr.c:238 [inline]
  tipc_subscrb_release_cb+0x17/0x30 net/tipc/subscr.c:316
  tipc_close_conn+0x171/0x270 net/tipc/server.c:204
  tipc_topsrv_kern_subscr+0x724/0x810 net/tipc/server.c:514
  tipc_group_create+0x702/0x9c0 net/tipc/group.c:184
  tipc_sk_join net/tipc/socket.c:2747 [inline]
  tipc_setsockopt+0x249/0xc10 net/tipc/socket.c:2861
  SYSC_setsockopt net/socket.c:1851 [inline]
  SyS_setsockopt+0x189/0x360 net/socket.c:1830
  entry_SYSCALL_64_fastpath+0x1f/0x96

Fixes: 14c04493cb ("tipc: add ability to order and receive topology events in driver")
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 14:51:59 -05:00
David S. Miller 7cda4cee13 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Small overlapping change conflict ('net' changed a line,
'net-next' added a line right afterwards) in flexcan.c

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-05 10:44:19 -05:00
Al Viro bc4802736d tipc: switch to sock_recvmsg()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-12-02 20:38:10 -05:00
Jon Maloy 4c94cc2d3d tipc: fall back to smaller MTU if allocation of local send skb fails
When sending node local messages the code is using an 'mtu' of 66060
bytes to avoid unnecessary fragmentation. During situations of low
memory tipc_msg_build() may sometimes fail to allocate such large
buffers, resulting in unnecessary send failures. This can easily be
remedied by falling back to a smaller MTU, and then reassemble the
buffer chain as if the message were arriving from a remote node.

At the same time, we change the initial MTU setting of the broadcast
link to a lower value, so that large messages always are fragmented
into smaller buffers even when we run in single node mode. Apart from
obtaining the same advantage as for the 'fallback' solution above, this
turns out to give a significant performance improvement. This can
probably be explained with the __pskb_copy() operation performed on the
buffer for each recipient during reception. We found the optimal value
for this, considering the most relevant skb pool, to be 3744 bytes.

Acked-by: Ying Xue <ying.xue@ericsson.com>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-01 15:21:25 -05:00
Tommi Rantala c7799c067c tipc: call tipc_rcv() only if bearer is up in tipc_udp_recv()
Remove the second tipc_rcv() call in tipc_udp_recv(). We have just
checked that the bearer is not up, and calling tipc_rcv() with a bearer
that is not up leads to a TIPC div-by-zero crash in
tipc_node_calculate_timer(). The crash is rare in practice, but can
happen like this:

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

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

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

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

Fixes: c9b64d492b ("tipc: add replicast peer discovery")
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-01 15:14:22 -05:00
Al Viro ade994f4f6 net: annotate ->poll() instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2017-11-27 16:20:04 -05:00
Jon Maloy 2e724dca77 tipc: eliminate access after delete in group_filter_msg()
KASAN revealed another access after delete in group.c. This time
it found that we read the header of a received message after the
buffer has been released.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-27 14:44:45 -05:00
Jon Maloy e0e853ac03 tipc: fix access of released memory
When the function tipc_group_filter_msg() finds that a member event
indicates that the member is leaving the group, it first deletes the
member instance, and then purges the message queue being handled
by the call. But the message queue is an aggregated field in the
just deleted item, leading the purge call to access freed memory.

We fix this by swapping the order of the two actions.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-21 20:22:03 +09:00
Jon Maloy d618d09a68 tipc: enforce valid ratio between skb truesize and contents
The socket level flow control is based on the assumption that incoming
buffers meet the condition (skb->truesize / roundup(skb->len) <= 4),
where the latter value is rounded off upwards to the nearest 1k number.
This does empirically hold true for the device drivers we know, but we
cannot trust that it will always be so, e.g., in a system with jumbo
frames and very small packets.

We now introduce a check for this condition at packet arrival, and if
we find it to be false, we copy the packet to a new, smaller buffer,
where the condition will be true. We expect this to affect only a small
fraction of all incoming packets, if at all.

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>
2017-11-16 10:49:00 +09:00
Jon Maloy 8d6e79d3ce tipc: improve link resiliency when rps is activated
Currently, the TIPC RPS dissector is based only on the incoming packets'
source node address, hence steering all traffic from a node to the same
core. We have seen that this makes the links vulnerable to starvation
and unnecessary resets when we turn down the link tolerance to very low
values.

To reduce the risk of this happening, we exempt probe and probe replies
packets from the convergence to one core per source node. Instead, we do
the opposite, - we try to diverge those packets across as many cores as
possible, by randomizing the flow selector key.

To make such packets identifiable to the dissector, we add a new
'is_keepalive' bit to word 0 of the LINK_PROTOCOL header. This bit is
set both for PROBE and PROBE_REPLY messages, and only for those.

It should be noted that these packets are not part of any flow anyway,
and only constitute a minuscule fraction of all packets sent across a
link. Hence, there is no risk that this will affect overall performance.

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>
2017-11-11 15:36:05 +09:00
David S. Miller 2a171788ba Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Files removed in 'net-next' had their license header updated
in 'net'.  We take the remove from 'net-next'.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-04 09:26:51 +09:00
Jon Maloy fa36882682 tipc: eliminate unnecessary probing
The neighbor monitor employs a threshold, default set to 32 peer nodes,
where it activates the "Overlapping Neighbor Monitoring" algorithm.
Below that threshold, monitoring is full-mesh, and no "domain records"
are passed between the nodes.

Because of this, a node never received a peer's ack that it has received
the most recent update of the own domain. Hence, the field 'acked_gen'
in struct tipc_monitor_state remains permamently at zero, whereas the
own domain generation is incremented for each added or removed peer.

This has the effect that the function tipc_mon_get_state() always sets
the field 'probing' in struct tipc_monitor_state true, again leading the
tipc_link_timeout() of the link in question to always send out a probe,
even when link->silent_intv_count is zero.

This is functionally harmless, but leads to some unncessary probing,
which can easily be eliminated by setting the 'probing' field of the
said struct correctly in such cases.

At the same time, we explictly invalidate the sent domain records when
the algorithm is not activated. This will eliminate any risk that an
invalid domain record might be inadverently accepted by the peer.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-03 15:48:46 +09:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00
Kees Cook 31b102bb50 net: tipc: Convert timers to use timer_setup()
In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Ying Xue <ying.xue@windriver.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Cc: tipc-discussion@lists.sourceforge.net
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-11-01 12:38:45 +09:00
Cong Wang e233df0157 tipc: fix a dangling pointer
tsk->group is set to grp earlier, but we forget to unset it
after grp is freed.

Fixes: 75da2163db ("tipc: introduce communication groups")
Reported-by: syzkaller bot
Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Ying Xue <ying.xue@windriver.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-26 17:46:53 +09:00
Jon Maloy f65163fed0 tipc: eliminate KASAN warning
The following warning was reported by syzbot on Oct 24. 2017:
KASAN: slab-out-of-bounds Read in tipc_nametbl_lookup_dst_nodes

This is a harmless bug, but we still want to get rid of the warning,
so we swap the two conditions in question.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-26 09:38:34 +09:00
Jon Maloy 0d5fcebf3c tipc: refactor tipc_sk_timeout() function
The function tipc_sk_timeout() is more complex than necessary, and
even seems to contain an undetected bug. At one of the occurences
where we renew the timer we just order it with (HZ / 20), instead
of (jiffies + HZ / 20);

In this commit we clean up the function.

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>
2017-10-22 02:36:35 +01:00
Jon Maloy cb4dc41eaa tipc: fix broken tipc_poll() function
In commit ae236fb208 ("tipc: receive group membership events via
member socket") we broke the tipc_poll() function by checking the
state of the receive queue before the call to poll_sock_wait(), while
relying that state afterwards, when it might have changed.

We restore this in this commit.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-21 12:27:05 +01:00
Dan Carpenter c75e427d93 tipc: checking for NULL instead of IS_ERR()
The tipc_alloc_conn() function never returns NULL, it returns error
pointers, so I have fixed the check.

Fixes: 14c04493cb ("tipc: add ability to order and receive topology events in driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-20 08:34:00 +01:00
Jon Maloy 36c0a9dfc6 tipc: fix rebasing error
In commit 2f487712b8 ("tipc: guarantee that group broadcast doesn't
bypass group unicast") there was introduced a last-minute rebasing
error that broke non-group communication.

We fix this here.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-16 21:28:36 +01:00
Jon Maloy 04d7b574b2 tipc: add multipoint-to-point flow control
We already have point-to-multipoint flow control within a group. But
we even need the opposite; -a scheme which can handle that potentially
hundreds of sources may try to send messages to the same destination
simultaneously without causing buffer overflow at the recipient. This
commit adds such a mechanism.

The algorithm works as follows:

- When a member detects a new, joining member, it initially set its
  state to JOINED and advertises a minimum window to the new member.
  This window is chosen so that the new member can send exactly one
  maximum sized message, or several smaller ones, to the recipient
  before it must stop and wait for an additional advertisement. This
  minimum window ADV_IDLE is set to 65 1kB blocks.

- When a member receives the first data message from a JOINED member,
  it changes the state of the latter to ACTIVE, and advertises a larger
  window ADV_ACTIVE = 12 x ADV_IDLE blocks to the sender, so it can
  continue sending with minimal disturbances to the data flow.

- The active members are kept in a dedicated linked list. Each time a
  message is received from an active member, it will be moved to the
  tail of that list. This way, we keep a record of which members have
  been most (tail) and least (head) recently active.

- There is a maximum number (16) of permitted simultaneous active
  senders per receiver. When this limit is reached, the receiver will
  not advertise anything immediately to a new sender, but instead put
  it in a PENDING state, and add it to a corresponding queue. At the
  same time, it will pick the least recently active member, send it an
  advertisement RECLAIM message, and set this member to state
  RECLAIMING.

- The reclaimee member has to respond with a REMIT message, meaning that
  it goes back to a send window of ADV_IDLE, and returns its unused
  advertised blocks beyond that value to the reclaiming member.

- When the reclaiming member receives the REMIT message, it unlinks
  the reclaimee from its active list, resets its state to JOINED, and
  notes that it is now back at ADV_IDLE advertised blocks to that
  member. If there are still unread data messages sent out by
  reclaimee before the REMIT, the member goes into an intermediate
  state REMITTED, where it stays until the said messages have been
  consumed.

- The returned advertised blocks can now be re-advertised to the
  pending member, which is now set to state ACTIVE and added to
  the active member list.

- To be proactive, i.e., to minimize the risk that any member will
  end up in the pending queue, we start reclaiming resources already
  when the number of active members exceeds 3/4 of the permitted
  maximum.

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>
2017-10-13 08:46:01 -07:00
Jon Maloy a3bada7066 tipc: guarantee delivery of last broadcast before DOWN event
The following scenario is possible:
- A user sends a broadcast message, and thereafter immediately leaves
  the group.
- The LEAVE message, following a different path than the broadcast,
  arrives ahead of the broadcast, and the sending member is removed
  from the receiver's list.
- The broadcast message arrives, but is dropped because the sender
  now is unknown to the receipient.

We fix this by sequence numbering membership events, just like ordinary
unicast messages. Currently, when a JOIN is sent to a peer, it contains
a synchronization point, - the sequence number of the next sent
broadcast, in order to give the receiver a start synchronization point.
We now let even LEAVE messages contain such an "end synchronization"
point, so that the recipient can delay the removal of the sending member
until it knows that all messages have been received.

The received synchronization points are added as sequence numbers to the
generated membership events, making it possible to handle them almost
the same way as regular unicasts in the receiving filter function. In
particular, a DOWN event with a too high sequence number will be kept
in the reordering queue until the missing broadcast(s) arrive and have
been delivered.

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>
2017-10-13 08:46:01 -07:00
Jon Maloy 399574d419 tipc: guarantee delivery of UP event before first broadcast
The following scenario is possible:
- A user joins a group, and immediately sends out a broadcast message
  to its members.
- The broadcast message, following a different data path than the
  initial JOIN message sent out during the joining procedure, arrives
  to a receiver before the latter..
- The receiver drops the message, since it is not ready to accept any
  messages until the JOIN has arrived.

We avoid this by treating group protocol JOIN messages like unicast
messages.
- We let them pass through the recipient's multicast input queue, just
  like ordinary unicasts.
- We force the first following broadacst to be sent as replicated
  unicast and being acknowledged by the recipient before accepting
  any more broadcast transmissions.

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>
2017-10-13 08:46:01 -07:00