Commit Graph

1290 Commits

Author SHA1 Message Date
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
Jon Maloy 2f487712b8 tipc: guarantee that group broadcast doesn't bypass group unicast
We need a mechanism guaranteeing that group unicasts sent out from a
socket are not bypassed by later sent broadcasts from the same socket.
We do this as follows:

- Each time a unicast is sent, we set a the broadcast method for the
  socket to "replicast" and "mandatory". This forces the first
  subsequent broadcast message to follow the same network and data path
  as the preceding unicast to a destination, hence preventing it from
  overtaking the latter.

- In order to make the 'same data path' statement above true, we let
  group unicasts pass through the multicast link input queue, instead
  of as previously through the unicast link input queue.

- In the first broadcast following a unicast, we set a new header flag,
  requiring all recipients to immediately acknowledge its reception.

- During the period before all the expected acknowledges are received,
  the socket refuses to accept any more broadcast attempts, i.e., by
  blocking or returning EAGAIN. This period should typically not be
  longer than a few microseconds.

- When all acknowledges have been received, the sending socket will
  open up for subsequent broadcasts, this time giving the link layer
  freedom to itself select the best transmission method.

- The forced and/or abrupt transmission method changes described above
  may lead to broadcasts arriving out of order to the recipients. We
  remedy this by introducing code that checks and if necessary
  re-orders such messages at the receiving end.

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 b87a5ea31c tipc: guarantee group unicast doesn't bypass group broadcast
Group unicast messages don't follow the same path as broadcast messages,
and there is a high risk that unicasts sent from a socket might bypass
previously sent broadcasts from the same socket.

We fix this by letting all unicast messages carry the sequence number of
the next sent broadcast from the same node, but without updating this
number at the receiver. This way, a receiver can check and if necessary
re-order such messages before they are added to the socket receive buffer.

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 5b8dddb637 tipc: introduce group multicast messaging
The previously introduced message transport to all group members is
based on the tipc multicast service, but is logically a broadcast
service within the group, and that is what we call it.

We now add functionality for sending messages to all group members
having a certain identity. Correspondingly, we call this feature 'group
multicast'. The service is using unicast when only one destination is
found, otherwise it will use the bearer broadcast service to transfer
the messages. In the latter case, the receiving members filter arriving
messages by looking at the intended destination instance. If there is
no match, the message will be dropped, while still being considered
received and read as seen by the flow control mechanism.

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 ee106d7f94 tipc: introduce group anycast messaging
In this commit, we make it possible to send connectionless unicast
messages to any member corresponding to the given member identity,
when there is more than one such member. The sender must use a
TIPC_ADDR_NAME address to achieve this effect.

We also perform load balancing between the destinations, i.e., we
primarily select one which has advertised sufficient send window
to not cause a block/EAGAIN delay, if any. This mechanism is
overlayed on the always present round-robin selection.

Anycast messages are subject to the same start synchronization
and flow control mechanism as group broadcast messages.

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 08:46:00 -07:00
Jon Maloy 27bd9ec027 tipc: introduce group unicast messaging
We now make it possible to send connectionless unicast messages
within a communication group. To send a message, the sender can use
either a direct port address, aka port identity, or an indirect port
name to be looked up.

This type of messages are subject to the same start synchronization
and flow control mechanism as group broadcast messages.

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 08:46:00 -07:00
Jon Maloy b7d4263551 tipc: introduce flow control for group broadcast messages
We introduce an end-to-end flow control mechanism for group broadcast
messages. This ensures that no messages are ever lost because of
destination receive buffer overflow, with minimal impact on performance.
For now, the algorithm is based on the assumption that there is only one
active transmitter at any moment in time.

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 08:46:00 -07:00
Jon Maloy ae236fb208 tipc: receive group membership events via member socket
Like with any other service, group members' availability can be
subscribed for by connecting to be topology server. However, because
the events arrive via a different socket than the member socket, there
is a real risk that membership events my arrive out of synch with the
actual JOIN/LEAVE action. I.e., it is possible to receive the first
messages from a new member before the corresponding JOIN event arrives,
just as it is possible to receive the last messages from a leaving
member after the LEAVE event has already been received.

Since each member socket is internally also subscribing for membership
events, we now fix this problem by passing those events on to the user
via the member socket. We leverage the already present member synch-
ronization protocol to guarantee correct message/event order. An event
is delivered to the user as an empty message where the two source
addresses identify the new/lost member. Furthermore, we set the MSG_OOB
bit in the message flags to mark it as an event. If the event is an
indication about a member loss we also set the MSG_EOR bit, so it can
be distinguished from a member addition event.

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 08:46:00 -07:00
Jon Maloy 31c82a2d9d tipc: add second source address to recvmsg()/recvfrom()
With group communication, it becomes important for a message receiver to
identify not only from which socket (identfied by a node:port tuple) the
message was sent, but also the logical identity (type:instance) of the
sending member.

We fix this by adding a second instance of struct sockaddr_tipc to the
source address area when a message is read. The extra address struct
is filled in with data found in the received message header (type,) and
in the local member representation struct (instance.)

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 08:46:00 -07:00
Jon Maloy 75da2163db tipc: introduce communication groups
As a preparation for introducing flow control for multicast and datagram
messaging we need a more strictly defined framework than we have now. A
socket must be able keep track of exactly how many and which other
sockets it is allowed to communicate with at any moment, and keep the
necessary state for those.

We therefore introduce a new concept we have named Communication Group.
Sockets can join a group via a new setsockopt() call TIPC_GROUP_JOIN.
The call takes four parameters: 'type' serves as group identifier,
'instance' serves as an logical member identifier, and 'scope' indicates
the visibility of the group (node/cluster/zone). Finally, 'flags' makes
it possible to set certain properties for the member. For now, there is
only one flag, indicating if the creator of the socket wants to receive
a copy of broadcast or multicast messages it is sending via the socket,
and if wants to be eligible as destination for its own anycasts.

A group is closed, i.e., sockets which have not joined a group will
not be able to send messages to or receive messages from members of
the group, and vice versa.

Any member of a group can send multicast ('group broadcast') messages
to all group members, optionally including itself, using the primitive
send(). The messages are received via the recvmsg() primitive. A socket
can only be member of one group at a time.

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 08:46:00 -07:00
Jon Maloy a80ae5306a tipc: improve destination linked list
We often see a need for a linked list of destination identities,
sometimes containing a port number, sometimes a node identity, and
sometimes both. The currently defined struct u32_list is not generic
enough to cover all cases, so we extend it to contain two u32 integers
and rename it to struct tipc_dest_list.

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 08:46:00 -07:00
Jon Maloy f70d37b796 tipc: add new function for sending multiple small messages
We see an increasing need to send multiple single-buffer messages
of TIPC_SYSTEM_IMPORTANCE to different individual destination nodes.
Instead of looping over the send queue and sending each buffer
individually, as we do now, we add a new help function
tipc_node_distr_xmit() to do this.

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 08:46:00 -07:00
Jon Maloy 64ac5f5977 tipc: refactor function filter_rcv()
In the following commits we will need to handle multiple incoming and
rejected/returned buffers in the function socket.c::filter_rcv().
As a preparation for this, we generalize the function by handling
buffer queues instead of individual buffers. We also introduce a
help function tipc_skb_reject(), and rename filter_rcv() to
tipc_sk_filter_rcv() in line with other functions in socket.c.

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 08:46:00 -07:00
Jon Maloy 38077b8ef8 tipc: add ability to obtain node availability status from other files
In the coming commits, functions at the socket level will need the
ability to read the availability status of a given node. We therefore
introduce a new function for this purpose, while renaming the existing
static function currently having the wanted name.

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 08:46:00 -07:00
Jon Maloy 23998835be tipc: improve address sanity check in tipc_connect()
The address given to tipc_connect() is not completely sanity checked,
under the assumption that this will be done later in the function
__tipc_sendmsg() when the address is used there.

However, the latter functon will in the next commits serve as caller
to several other send functions, so we want to move the corresponding
sanity check there to the beginning of that function, before we possibly
need to grab the address stored by tipc_connect(). We must therefore
be able to trust that this address already has been thoroughly checked.

We do this in this commit.

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 08:46:00 -07:00
Jon Maloy 14c04493cb tipc: add ability to order and receive topology events in driver
As preparation for introducing communication groups, we add the ability
to issue topology subscriptions and receive topology events from kernel
space. This will make it possible for group member sockets to keep track
of other group members.

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 08:46:00 -07:00
Jon Maloy a9e2971b8c tipc: Unclone message at secondary destination lookup
When a bundling message is received, the function tipc_link_input()
calls function tipc_msg_extract() to unbundle all inner messages of
the bundling message before adding them to input queue.

The function tipc_msg_extract() just clones all inner skb for all
inner messagges from the bundling skb. This means that the skb
headroom of an inner message overlaps with the data part of the
preceding message in the bundle.

If the message in question is a name addressed message, it may be
subject to a secondary destination lookup, and eventually be sent out
on one of the interfaces again. But, since what is perceived as headroom
by the device driver in reality is the last bytes of the preceding
message in the bundle, the latter will be overwritten by the MAC
addresses of the L2 header. If the preceding message has not yet been
consumed by the user, it will evenually be delivered with corrupted
contents.

This commit fixes this by uncloning all messages passing through the
function tipc_msg_lookup_dest(), hence ensuring that the headroom
is always valid when the message is passed on.

Signed-off-by: Tung Nguyen <tung.q.nguyen@dektech.com.au>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-08 21:13:23 -07:00
Jon Maloy 3382605fd8 tipc: correct initialization of skb list
We change the initialization of the skb transmit buffer queues
in the functions tipc_bcast_xmit() and tipc_rcast_xmit() to also
initialize their spinlocks. This is needed because we may, during
error conditions, need to call skb_queue_purge() on those queues
further down the stack.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-08 21:13:23 -07:00
Parthasarathy Bhuvaragan aad06212d3 tipc: use only positive error codes in messages
In commit e3a77561e7 ("tipc: split up function tipc_msg_eval()"),
we have updated the function tipc_msg_lookup_dest() to set the error
codes to negative values at destination lookup failures. Thus when
the function sets the error code to -TIPC_ERR_NO_NAME, its inserted
into the 4 bit error field of the message header as 0xf instead of
TIPC_ERR_NO_NAME (1). The value 0xf is an unknown error code.

In this commit, we set only positive error code.

Fixes: e3a77561e7 ("tipc: split up function tipc_msg_eval()")
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-10-01 04:03:35 +01:00
Kleber Sacilotto de Souza 8e0deed924 tipc: remove unnecessary call to dev_net()
The net device is already stored in the 'net' variable, so no need to call
dev_net() again.

Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Acked-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-06 21:25:52 -07:00
David S. Miller 6026e043d0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Three cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>
2017-09-01 17:42:05 -07:00
Parthasarathy Bhuvaragan d55c60eba0 tipc: permit bond slave as bearer
For a bond slave device as a tipc bearer, the dev represents the bond
interface and orig_dev represents the slave in tipc_l2_rcv_msg().
Since we decode the tipc_ptr from bonding device (dev), we fail to
find the bearer and thus tipc links are not established.

In this commit, we register the tipc protocol callback per device and
look for tipc bearer from both the devices.

Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-29 15:07:33 -07:00
Parthasarathy Bhuvaragan 991ca84daa tipc: context imbalance at node read unlock
If we fail to find a valid bearer in tipc_node_get_linkname(),
node_read_unlock() is called without holding the node read lock.

This commit fixes this error.

Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-24 21:54:34 -07:00
Parthasarathy Bhuvaragan 60d1d93664 tipc: reassign pointers after skb reallocation / linearization
In tipc_msg_reverse(), we assign skb attributes to local pointers
in stack at startup. This is followed by skb_linearize() and for
cloned buffers we perform skb relocation using pskb_expand_head().
Both these methods may update the skb attributes and thus making
the pointers incorrect.

In this commit, we fix this error by ensuring that the pointers
are re-assigned after any of these skb operations.

Fixes: 29042e19f2 ("tipc: let function tipc_msg_reverse() expand header
when needed")
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-24 21:54:34 -07:00
Parthasarathy Bhuvaragan 27163138b4 tipc: perform skb_linearize() before parsing the inner header
In tipc_rcv(), we linearize only the header and usually the packets
are consumed as the nodes permit direct reception. However, if the
skb contains tunnelled message due to fail over or synchronization
we parse it in tipc_node_check_state() without performing
linearization. This will cause link disturbances if the skb was
non linear.

In this commit, we perform linearization for the above messages.

Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-24 21:54:34 -07:00
Bob Peterson 6c7e983b22 tipc: Fix tipc_sk_reinit handling of -EAGAIN
In 9dbbfb0ab6 function tipc_sk_reinit
had additional logic added to loop in the event that function
rhashtable_walk_next() returned -EAGAIN. No worries.

However, if rhashtable_walk_start returns -EAGAIN, it does "continue",
and therefore skips the call to rhashtable_walk_stop(). That has
the effect of calling rcu_read_lock() without its paired call to
rcu_read_unlock(). Since rcu_read_lock() may be nested, the problem
may not be apparent for a while, especially since resize events may
be rare. But the comments to rhashtable_walk_start() state:

 * ...Note that we take the RCU lock in all
 * cases including when we return an error.  So you must always call
 * rhashtable_walk_stop to clean up.

This patch replaces the continue with a goto and label to ensure a
matching call to rhashtable_walk_stop().

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-24 14:02:26 -07:00
Arvind Yadav 042a90106b net: tipc: constify genl_ops
genl_ops are not supposed to change at runtime. All functions
working with genl_ops provided by <net/genetlink.h> work with
const genl_ops. So mark the non-const structs as const.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-23 22:31:38 -07:00
Ying Xue fd849b7c41 tipc: fix a race condition of releasing subscriber object
No matter whether a request is inserted into workqueue as a work item
to cancel a subscription or to delete a subscription's subscriber
asynchronously, the work items may be executed in different workers.
As a result, it doesn't mean that one request which is raised prior to
another request is definitely handled before the latter. By contrast,
if the latter request is executed before the former request, below
error may happen:

[  656.183644] BUG: spinlock bad magic on CPU#0, kworker/u8:0/12117
[  656.184487] general protection fault: 0000 [#1] SMP
[  656.185160] Modules linked in: tipc ip6_udp_tunnel udp_tunnel 9pnet_virtio 9p 9pnet virtio_net virtio_pci virtio_ring virtio [last unloaded: ip6_udp_tunnel]
[  656.187003] CPU: 0 PID: 12117 Comm: kworker/u8:0 Not tainted 4.11.0-rc7+ #6
[  656.187920] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  656.188690] Workqueue: tipc_rcv tipc_recv_work [tipc]
[  656.189371] task: ffff88003f5cec40 task.stack: ffffc90004448000
[  656.190157] RIP: 0010:spin_bug+0xdd/0xf0
[  656.190678] RSP: 0018:ffffc9000444bcb8 EFLAGS: 00010202
[  656.191375] RAX: 0000000000000034 RBX: ffff88003f8d1388 RCX: 0000000000000000
[  656.192321] RDX: ffff88003ba13708 RSI: ffff88003ba0cd08 RDI: ffff88003ba0cd08
[  656.193265] RBP: ffffc9000444bcd0 R08: 0000000000000030 R09: 000000006b6b6b6b
[  656.194208] R10: ffff8800bde3e000 R11: 00000000000001b4 R12: 6b6b6b6b6b6b6b6b
[  656.195157] R13: ffffffff81a3ca64 R14: ffff88003f8d1388 R15: ffff88003f8d13a0
[  656.196101] FS:  0000000000000000(0000) GS:ffff88003ba00000(0000) knlGS:0000000000000000
[  656.197172] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  656.197935] CR2: 00007f0b3d2e6000 CR3: 000000003ef9e000 CR4: 00000000000006f0
[  656.198873] Call Trace:
[  656.199210]  do_raw_spin_lock+0x66/0xa0
[  656.199735]  _raw_spin_lock_bh+0x19/0x20
[  656.200258]  tipc_subscrb_subscrp_delete+0x28/0xf0 [tipc]
[  656.200990]  tipc_subscrb_rcv_cb+0x45/0x260 [tipc]
[  656.201632]  tipc_receive_from_sock+0xaf/0x100 [tipc]
[  656.202299]  tipc_recv_work+0x2b/0x60 [tipc]
[  656.202872]  process_one_work+0x157/0x420
[  656.203404]  worker_thread+0x69/0x4c0
[  656.203898]  kthread+0x138/0x170
[  656.204328]  ? process_one_work+0x420/0x420
[  656.204889]  ? kthread_create_on_node+0x40/0x40
[  656.205527]  ret_from_fork+0x29/0x40
[  656.206012] Code: 48 8b 0c 25 00 c5 00 00 48 c7 c7 f0 24 a3 81 48 81 c1 f0 05 00 00 65 8b 15 61 ef f5 7e e8 9a 4c 09 00 4d 85 e4 44 8b 4b 08 74 92 <45> 8b 84 24 40 04 00 00 49 8d 8c 24 f0 05 00 00 eb 8d 90 0f 1f
[  656.208504] RIP: spin_bug+0xdd/0xf0 RSP: ffffc9000444bcb8
[  656.209798] ---[ end trace e2a800e6eb0770be ]---

In above scenario, the request of deleting subscriber was performed
earlier than the request of canceling a subscription although the
latter was issued before the former, which means tipc_subscrb_delete()
was called before tipc_subscrp_cancel(). As a result, when
tipc_subscrb_subscrp_delete() called by tipc_subscrp_cancel() was
executed to cancel a subscription, the subscription's subscriber
refcnt had been decreased to 1. After tipc_subscrp_delete() where
the subscriber was freed because its refcnt was decremented to zero,
but the subscriber's lock had to be released, as a consequence, panic
happened.

By contrast, if we increase subscriber's refcnt before
tipc_subscrb_subscrp_delete() is called in tipc_subscrp_cancel(),
the panic issue can be avoided.

Fixes: d094c4d5f5 ("tipc: add subscription refcount to avoid invalid delete")
Reported-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-22 14:25:02 -07:00
Parthasarathy Bhuvaragan 458be024ef tipc: remove subscription references only for pending timers
In commit, 139bb36f75 ("tipc: advance the time of deleting
subscription from subscriber->subscrp_list"), we delete the
subscription from the subscribers list and from nametable
unconditionally. This leads to the following bug if the timer
running tipc_subscrp_timeout() in another CPU accesses the
subscription list after the subscription delete request.

[39.570] general protection fault: 0000 [#1] SMP
::
[39.574] task: ffffffff81c10540 task.stack: ffffffff81c00000
[39.575] RIP: 0010:tipc_subscrp_timeout+0x32/0x80 [tipc]
[39.576] RSP: 0018:ffff88003ba03e90 EFLAGS: 00010282
[39.576] RAX: dead000000000200 RBX: ffff88003f0f3600 RCX: 0000000000000101
[39.577] RDX: dead000000000100 RSI: 0000000000000201 RDI: ffff88003f0d7948
[39.578] RBP: ffff88003ba03ea0 R08: 0000000000000001 R09: ffff88003ba03ef8
[39.579] R10: 000000000000014f R11: 0000000000000000 R12: ffff88003f0d7948
[39.580] R13: ffff88003f0f3618 R14: ffffffffa006c250 R15: ffff88003f0f3600
[39.581] FS:  0000000000000000(0000) GS:ffff88003ba00000(0000) knlGS:0000000000000000
[39.582] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[39.583] CR2: 00007f831c6e0714 CR3: 000000003d3b0000 CR4: 00000000000006f0
[39.584] Call Trace:
[39.584]  <IRQ>
[39.585]  call_timer_fn+0x3d/0x180
[39.585]  ? tipc_subscrb_rcv_cb+0x260/0x260 [tipc]
[39.586]  run_timer_softirq+0x168/0x1f0
[39.586]  ? sched_clock_cpu+0x16/0xc0
[39.587]  __do_softirq+0x9b/0x2de
[39.587]  irq_exit+0x60/0x70
[39.588]  smp_apic_timer_interrupt+0x3d/0x50
[39.588]  apic_timer_interrupt+0x86/0x90
[39.589] RIP: 0010:default_idle+0x20/0xf0
[39.589] RSP: 0018:ffffffff81c03e58 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
[39.590] RAX: 0000000000000000 RBX: ffffffff81c10540 RCX: 0000000000000000
[39.591] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[39.592] RBP: ffffffff81c03e68 R08: 0000000000000000 R09: 0000000000000000
[39.593] R10: ffffc90001cbbe00 R11: 0000000000000000 R12: 0000000000000000
[39.594] R13: ffffffff81c10540 R14: 0000000000000000 R15: 0000000000000000
[39.595]  </IRQ>
::
[39.603] RIP: tipc_subscrp_timeout+0x32/0x80 [tipc] RSP: ffff88003ba03e90
[39.604] ---[ end trace 79ce94b7216cb459 ]---

Fixes: 139bb36f75 ("tipc: advance the time of deleting subscription from subscriber->subscrp_list")
Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-22 14:25:02 -07:00
David S. Miller e2a7c34fb2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2017-08-21 17:06:42 -07:00
Jon Paul Maloy 40501f90ed tipc: don't reset stale broadcast send link
When the broadcast send link after 100 attempts has failed to
transfer a packet to all peers, we consider it stale, and reset
it. Thereafter it needs to re-synchronize with the peers, something
currently done by just resetting and re-establishing all links to
all peers. This has turned out to be overkill, with potentially
unwanted consequences for the remaining cluster.

A closer analysis reveals that this can be done much simpler. When
this kind of failure happens, for reasons that may lie outside the
TIPC protocol, it is typically only one peer which is failing to
receive and acknowledge packets. It is hence sufficient to identify
and reset the links only to that peer to resolve the situation, without
having to reset the broadcast link at all. This solution entails a much
lower risk of negative consequences for the own node as well as for
the overall cluster.

We implement this change in this commit.

Reviewed-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
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>
2017-08-21 13:37:45 -07:00
Eric Dumazet 5bfd37b4de tipc: fix use-after-free
syszkaller reported use-after-free in tipc [1]

When msg->rep skb is freed, set the pointer to NULL,
so that caller does not free it again.

[1]

==================================================================
BUG: KASAN: use-after-free in skb_push+0xd4/0xe0 net/core/skbuff.c:1466
Read of size 8 at addr ffff8801c6e71e90 by task syz-executor5/4115

CPU: 1 PID: 4115 Comm: syz-executor5 Not tainted 4.13.0-rc4+ #32
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:16 [inline]
 dump_stack+0x194/0x257 lib/dump_stack.c:52
 print_address_description+0x73/0x250 mm/kasan/report.c:252
 kasan_report_error mm/kasan/report.c:351 [inline]
 kasan_report+0x24e/0x340 mm/kasan/report.c:409
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report.c:430
 skb_push+0xd4/0xe0 net/core/skbuff.c:1466
 tipc_nl_compat_recv+0x833/0x18f0 net/tipc/netlink_compat.c:1209
 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:598
 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:623
 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:634
 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline]
 netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291
 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 sock_write_iter+0x31a/0x5d0 net/socket.c:898
 call_write_iter include/linux/fs.h:1743 [inline]
 new_sync_write fs/read_write.c:457 [inline]
 __vfs_write+0x684/0x970 fs/read_write.c:470
 vfs_write+0x189/0x510 fs/read_write.c:518
 SYSC_write fs/read_write.c:565 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:557
 entry_SYSCALL_64_fastpath+0x1f/0xbe
RIP: 0033:0x4512e9
RSP: 002b:00007f3bc8184c08 EFLAGS: 00000216 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000718000 RCX: 00000000004512e9
RDX: 0000000000000020 RSI: 0000000020fdb000 RDI: 0000000000000006
RBP: 0000000000000086 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000216 R12: 00000000004b5e76
R13: 00007f3bc8184b48 R14: 00000000004b5e86 R15: 0000000000000000

Allocated by task 4115:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
 kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:489
 kmem_cache_alloc_node+0x13d/0x750 mm/slab.c:3651
 __alloc_skb+0xf1/0x740 net/core/skbuff.c:219
 alloc_skb include/linux/skbuff.h:903 [inline]
 tipc_tlv_alloc+0x26/0xb0 net/tipc/netlink_compat.c:148
 tipc_nl_compat_dumpit+0xf2/0x3c0 net/tipc/netlink_compat.c:248
 tipc_nl_compat_handle net/tipc/netlink_compat.c:1130 [inline]
 tipc_nl_compat_recv+0x756/0x18f0 net/tipc/netlink_compat.c:1199
 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:598
 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:623
 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:634
 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline]
 netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291
 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 sock_write_iter+0x31a/0x5d0 net/socket.c:898
 call_write_iter include/linux/fs.h:1743 [inline]
 new_sync_write fs/read_write.c:457 [inline]
 __vfs_write+0x684/0x970 fs/read_write.c:470
 vfs_write+0x189/0x510 fs/read_write.c:518
 SYSC_write fs/read_write.c:565 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:557
 entry_SYSCALL_64_fastpath+0x1f/0xbe

Freed by task 4115:
 save_stack_trace+0x16/0x20 arch/x86/kernel/stacktrace.c:59
 save_stack+0x43/0xd0 mm/kasan/kasan.c:447
 set_track mm/kasan/kasan.c:459 [inline]
 kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
 __cache_free mm/slab.c:3503 [inline]
 kmem_cache_free+0x77/0x280 mm/slab.c:3763
 kfree_skbmem+0x1a1/0x1d0 net/core/skbuff.c:622
 __kfree_skb net/core/skbuff.c:682 [inline]
 kfree_skb+0x165/0x4c0 net/core/skbuff.c:699
 tipc_nl_compat_dumpit+0x36a/0x3c0 net/tipc/netlink_compat.c:260
 tipc_nl_compat_handle net/tipc/netlink_compat.c:1130 [inline]
 tipc_nl_compat_recv+0x756/0x18f0 net/tipc/netlink_compat.c:1199
 genl_family_rcv_msg+0x7b7/0xfb0 net/netlink/genetlink.c:598
 genl_rcv_msg+0xb2/0x140 net/netlink/genetlink.c:623
 netlink_rcv_skb+0x216/0x440 net/netlink/af_netlink.c:2397
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:634
 netlink_unicast_kernel net/netlink/af_netlink.c:1265 [inline]
 netlink_unicast+0x4e8/0x6f0 net/netlink/af_netlink.c:1291
 netlink_sendmsg+0xa4a/0xe60 net/netlink/af_netlink.c:1854
 sock_sendmsg_nosec net/socket.c:633 [inline]
 sock_sendmsg+0xca/0x110 net/socket.c:643
 sock_write_iter+0x31a/0x5d0 net/socket.c:898
 call_write_iter include/linux/fs.h:1743 [inline]
 new_sync_write fs/read_write.c:457 [inline]
 __vfs_write+0x684/0x970 fs/read_write.c:470
 vfs_write+0x189/0x510 fs/read_write.c:518
 SYSC_write fs/read_write.c:565 [inline]
 SyS_write+0xef/0x220 fs/read_write.c:557
 entry_SYSCALL_64_fastpath+0x1f/0xbe

The buggy address belongs to the object at ffff8801c6e71dc0
 which belongs to the cache skbuff_head_cache of size 224
The buggy address is located 208 bytes inside of
 224-byte region [ffff8801c6e71dc0, ffff8801c6e71ea0)
The buggy address belongs to the page:
page:ffffea00071b9c40 count:1 mapcount:0 mapping:ffff8801c6e71000 index:0x0
flags: 0x200000000000100(slab)
raw: 0200000000000100 ffff8801c6e71000 0000000000000000 000000010000000c
raw: ffffea0007224a20 ffff8801d98caf48 ffff8801d9e79040 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8801c6e71d80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
 ffff8801c6e71e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801c6e71e80: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc
                         ^
 ffff8801c6e71f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8801c6e71f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Dmitry Vyukov  <dvyukov@google.com>
Cc: Jon Maloy <jon.maloy@ericsson.com>
Cc: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-18 15:59:29 -07:00
Jon Paul Maloy 59a361bc6f tipc: avoid inheriting msg_non_seq flag when message is returned
In the function msg_reverse(), we reverse the header while trying to
reuse the original buffer whenever possible. Those rejected/returned
messages are always transmitted as unicast, but the msg_non_seq field
is not explicitly set to zero as it should be.

We have seen cases where multicast senders set the message type to
"NOT dest_droppable", meaning that a multicast message shorter than
one MTU will be returned, e.g., during receive buffer overflow, by
reusing the original buffer. This has the effect that even the
'msg_non_seq' field is inadvertently inherited by the rejected message,
although it is now sent as a unicast message. This again leads the
receiving unicast link endpoint to steer the packet toward the broadcast
link receive function, where it is dropped. The affected unicast link is
thereafter (after 100 failed retransmissions) declared 'stale' and
reset.

We fix this by unconditionally setting the 'msg_non_seq' flag to zero
for all rejected/returned messages.

Reported-by: Canh Duc Luu <canh.d.luu@dektech.com.au>
Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-14 11:20:36 -07:00
Jon Paul Maloy fed5f5718c tipc: accept PACKET_MULTICAST packets
On L2 bearers, the TIPC broadcast function is sending out packets using
the corresponding L2 broadcast address. At reception, we filter such
packets under the assumption that they will also be delivered as
broadcast packets.

This assumption doesn't always hold true. Under high load, we have seen
that a switch may convert the destination address and deliver the packet
as a PACKET_MULTICAST, something leading to inadvertently dropped
packets and a stale and reset broadcast link.

We fix this by extending the reception filtering to accept packets of
type PACKET_MULTICAST.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-14 11:19:25 -07:00
Jon Paul Maloy ed43594aed tipc: remove premature ESTABLISH FSM event at link synchronization
When a link between two nodes come up, both endpoints will initially
send out a STATE message to the peer, to increase the probability that
the peer endpoint also is up when the first traffic message arrives.
Thereafter, if the establishing link is the second link between two
nodes, this first "traffic" message is a TUNNEL_PROTOCOL/SYNCH message,
helping the peer to perform initial synchronization between the two
links.

However, the initial STATE message may be lost, in which case the SYNCH
message will be the first one arriving at the peer. This should also
work, as the SYNCH message itself will be used to take up the link
endpoint before  initializing synchronization.

Unfortunately the code for this case is broken. Currently, the link is
brought up through a tipc_link_fsm_evt(ESTABLISHED) when a SYNCH
arrives, whereupon __tipc_node_link_up() is called to distribute the
link slots and take the link into traffic. But, __tipc_node_link_up() is
itself starting with a test for whether the link is up, and if true,
returns without action. Clearly, the tipc_link_fsm_evt(ESTABLISHED) call
is unnecessary, since tipc_node_link_up() is itself issuing such an
event, but also harmful, since it inhibits tipc_node_link_up() to
perform the test of its tasks, and the link endpoint in question hence
is never taken into traffic.

This problem has been exposed when we set up dual links between pre-
and post-4.4 kernels, because the former ones don't send out the
initial STATE message described above.

We fix this by removing the unnecessary event call.

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-09 22:38:06 -07:00
Reshetova, Elena 41c6d650f6 net: convert sock.sk_refcnt from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.

This patch uses refcount_inc_not_zero() instead of
atomic_inc_not_zero_hint() due to absense of a _hint()
version of refcount API. If the hint() version must
be used, we might need to revisit API.

Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-01 07:39:08 -07:00
Jia-Ju Bai 343eba69c6 net: tipc: Fix a sleep-in-atomic bug in tipc_msg_reverse
The kernel may sleep under a rcu read lock in tipc_msg_reverse, and the
function call path is:
tipc_l2_rcv_msg (acquire the lock by rcu_read_lock)
  tipc_rcv
    tipc_sk_rcv
      tipc_msg_reverse
        pskb_expand_head(GFP_KERNEL) --> may sleep
tipc_node_broadcast
  tipc_node_xmit_skb
    tipc_node_xmit
      tipc_sk_rcv
        tipc_msg_reverse
          pskb_expand_head(GFP_KERNEL) --> may sleep

To fix it, "GFP_KERNEL" is replaced with "GFP_ATOMIC".

Signed-off-by: Jia-Ju Bai <baijiaju1990@163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-06-10 18:20:38 -04:00