Make netdev queue packets if we run out of credits.
Signed-off-by: NLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Rely on netif_wake_queue and netif_stop_queue to flow control when
transmit resources are unavailable.
Signed-off-by: NLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Since l2cap_chan_send will now queue the packets there is no point in
checking the credits anymore.
Signed-off-by: NLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This makes should make it more clear why a packet is being dropped.
Signed-off-by: NLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

During chan_recv_cb there is already a peer lookup which can be passed
to recv_pkt directly instead of the channel.
Signed-off-by: NLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

A status field in the skb_cb struct was storing a channel status
based on channel suspend/resume events.  This stored status was
then used to return EAGAIN if there were packet sending issues
in snd_pkt().

The issue is that the skb has been freed by the time the callback
to 6lowpan's suspend/resume was called.  So, this generates a
"use after free" issue that was noticed while running kernel tests
with KASAN debug enabled.

Let's eliminate the status field entirely as we can use the channel
tx_credits to indicate whether we should return EAGAIN when handling
packets.
Signed-off-by: NMichael Scott <michael.scott@linaro.org>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

When adding 6lowpan devices very rapidly we sometimes see a crash:
[23122.306615] CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.9.0-43-arm64 #1 Debian 4.9.9.linaro.43-1
[23122.315400] Hardware name: HiKey Development Board (DT)
[23122.320623] task: ffff800075443080 task.stack: ffff800075484000
[23122.326551] PC is at expire_timers+0x70/0x150
[23122.330907] LR is at run_timer_softirq+0xa0/0x1a0
[23122.335616] pc : [<ffff000008142dd8>] lr : [<ffff000008142f58>] pstate: 600001c5

This was due to add_peer_chan() unconditionally initializing the
lowpan_btle_dev->notify_peers delayed work structure, even if the
lowpan_btle_dev passed into add_peer_chan() had previously been
initialized.

Normally, this would go unnoticed as the delayed work timer is set for
100 msec, however when calling add_peer_chan() faster than 100 msec it
clears out a previously queued delay work causing the crash above.

To fix this, let add_peer_chan() know when a new lowpan_btle_dev is passed
in so that it only performs the delay work initialization when needed.
Signed-off-by: NMichael Scott <michael.scott@linaro.org>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The data from peer->chan->dst is not being copied to peer_addr, the
current code just updates the pointer and not the contents of what
it points to.  Fix this with the intended assignment.

Detected by CoverityScan, CID#1422111 ("Parse warning
(PW.PARAM_SET_BUT_NOT_USED)")

Fixes: fb6f2f606ce8 ("6lowpan: Fix IID format for Bluetooth")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Reviewed-by: NLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

According to RFC 7668 U/L bit shall not be used:

https://wiki.tools.ietf.org/html/rfc7668#section-3.2.2 [Page 10]:

   In the figure, letter 'b' represents a bit from the
   Bluetooth device address, copied as is without any changes on any
   bit.  This means that no bit in the IID indicates whether the
   underlying Bluetooth device address is public or random.

   |0              1|1              3|3              4|4              6|
   |0              5|6              1|2              7|8              3|
   +----------------+----------------+----------------+----------------+
   |bbbbbbbbbbbbbbbb|bbbbbbbb11111111|11111110bbbbbbbb|bbbbbbbbbbbbbbbb|
   +----------------+----------------+----------------+----------------+

Because of this the code cannot figure out the address type from the IP
address anymore thus it makes no sense to use peer_lookup_ba as it needs
the peer address type.
Signed-off-by: NLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This allow technologies such as Bluetooth to use its native lladdr which
is eui48 instead of eui64 which was expected by functions like
lowpan_header_decompress and lowpan_header_compress.
Signed-off-by: NLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Set BTLE MAC addresses that are 6 bytes long and not 8 bytes
that are used in other places with 6lowpan.
Signed-off-by: NPatrik Flykt <patrik.flykt@linux.intel.com>
Signed-off-by: NLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Since we need to change the implementation, stop exposing internals.

Provide kref_read() to read the current reference count; typically
used for debug messages.

Kills two anti-patterns:

	atomic_read(&kref->refcount)
	kref->refcount.counter
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NIngo Molnar <mingo@kernel.org>

The hci_get_route() API is used to look up local HCI devices, however
so far it has been incapable of dealing with anything else than the
public address of HCI devices. This completely breaks with LE-only HCI
devices that do not come with a public address, but use a static
random address instead.

This patch exteds the hci_get_route() API with a src_type parameter
that's used for comparing with the right address of each HCI device.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

It is time to add netdev_lockdep_set_classes() helper
so that lockdep annotations per device type are easier to manage.

This removes a lot of copies and missing annotations.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of using a single bit (__QDISC___STATE_RUNNING)
in sch->__state, use a seqcount.

This adds lockdep support, but more importantly it will allow us
to sample qdisc/class statistics without having to grab qdisc root lock.
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The memcpy of ipv6 header destination address to the skb control block
(sbk->cb) in header_create() results in currupted memory when bt_xmit()
is issued. The skb->cb is "released" in the return of header_create()
making room for lower layer to minipulate the skb->cb.

The value retrieved in bt_xmit is not persistent across header creation
and sending, and the lower layer will overwrite portions of skb->cb,
making the copied destination address wrong.

The memory corruption will lead to non-working multicast as the first 4
bytes of the copied destination address is replaced by a value that
resolves into a non-multicast prefix.

This fix removes the dependency on the skb control block between header
creation and send, by moving the destination address memcpy to the send
function path (setup_create, which is called from bt_xmit).
Signed-off-by: NGlenn Ruben Bakke <glenn.ruben.bakke@nordicsemi.no>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org # 4.5+

This patch changes the naming for interface private data for lowpan
intefaces. The current private data scheme is:

-------------------------------------------------
|    6LoWPAN Generic   |    LinkLayer 6LoWPAN   |
-------------------------------------------------

the current naming schemes are:

- 6LoWPAN Generic:
  - lowpan_priv
- LinkLayer 6LoWPAN:
  - BTLE
    - lowpan_dev
  - 802.15.4:
    - lowpan_dev_info

the new naming scheme with this patch will be:

- 6LoWPAN Generic:
  - lowpan_dev
- LinkLayer 6LoWPAN:
  - BTLE
    - lowpan_btle_dev
  - 802.15.4:
    - lowpan_802154_dev
Signed-off-by: NAlexander Aring <aar@pengutronix.de>
Reviewed-by: Stefan Schmidt<stefan@osg.samsung.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch fixes incorrect handling of the 6lowpan packets that contain
uncompressed IPv6 header.

RFC4944 specifies a special dispatch for 6lowpan to carry uncompressed
IPv6 header. This dispatch (1 byte long) has to be removed during
reception and skb data pointer has to be moved. To correctly point in
the beginning of the IPv6 header the dispatch byte has to be pulled off
before packet can be processed by netif_rx_in().

Test scenario: IPv6 packets are not correctly interpreted by the network
layer when IPv6 header is not compressed (e.g. ICMPv6 Echo Reply is not
propagated correctly to the ICMPv6 layer because the extra byte will make
the header look corrupted).

Similar approach is done for IEEE 802.15.4.
Signed-off-by: NLukasz Duda <lukasz.duda@nordicsemi.no>
Signed-off-by: NGlenn Ruben Bakke <glenn.ruben.bakke@nordicsemi.no>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Cc: stable@vger.kernel.org # 4.4+

The fixes provided in this patch assigns a valid net_device structure to
skb before dispatching it for further processing.

Scenario #1:
============

Bluetooth 6lowpan receives an uncompressed IPv6 header, and dispatches it
to netif. The following error occurs:

Null pointer dereference error #1 crash log:

[  845.854013] BUG: unable to handle kernel NULL pointer dereference at
               0000000000000048
[  845.855785] IP: [<ffffffff816e3d36>] enqueue_to_backlog+0x56/0x240
...
[  845.909459] Call Trace:
[  845.911678]  [<ffffffff816e3f64>] netif_rx_internal+0x44/0xf0

The first modification fixes the NULL pointer dereference error by
assigning dev to the local_skb in order to set a valid net_device before
processing the skb by netif_rx_ni().

Scenario #2:
============

Bluetooth 6lowpan receives an UDP compressed message which needs further
decompression by nhc_udp. The following error occurs:

Null pointer dereference error #2 crash log:

[   63.295149] BUG: unable to handle kernel NULL pointer dereference at
               0000000000000840
[   63.295931] IP: [<ffffffffc0559540>] udp_uncompress+0x320/0x626
               [nhc_udp]

The second modification fixes the NULL pointer dereference error by
assigning dev to the local_skb in the case of a udp compressed packet.
The 6lowpan udp_uncompress function expects that the net_device is set in
the skb when checking lltype.
Signed-off-by: NGlenn Ruben Bakke <glenn.ruben.bakke@nordicsemi.no>
Signed-off-by: NLukasz Duda <lukasz.duda@nordicsemi.no>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Cc: stable@vger.kernel.org # 4.4+

This patch introduces register and unregister functionality for lowpan
interfaces. While register a lowpan interface there are several things
which need to be initialize by the 6lowpan subsystem. Upcoming
functionality need to register/unregister per interface components e.g.
debugfs entry.
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Jukka reported about the following warning:

"NOHZ: local_softirq_pending 08"

I remember this warning and we had a similar issue when using workqueues
and calling netif_rx. See commit 5ff3fec6 ("mac802154: fix NOHZ
local_softirq_pending 08 warning").

This warning occurs when calling "netif_rx" inside the wrong context
(non softirq context). The net core api offers "netif_rx_ni" to call
netif_rx inside the correct softirq context.
Reported-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Use the new hci_conn_hash_lookup_le() API to look up LE connections.
This way we're guaranteed exact matches that also take into account
the address type.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch changes the lowpan_header_decompress function by removing
inklayer related information from parameters. This is currently for
supporting short and extended address for iphc handling in 802154.
We don't support short address handling anyway right now, but there
exists already code for handling short addresses in
lowpan_header_decompress.

The address parameters are also changed to a void pointer, so 6LoWPAN
linklayer specific code can put complex structures as these parameters
and cast it again inside the generic code by evaluating linklayer type
before. The order is also changed by destination address at first and
then source address, which is the same like all others functions where
destination is always the first, memcpy, dev_hard_header,
lowpan_header_compress, etc.

This patch also moves the fetching of iphc values from 6LoWPAN linklayer
specific code into the generic branch.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch changes the lowpan_header_compress function by removing
unused parameters like "len" and drop static value parameters of
protocol type. Instead we really check the protocol type inside inside
the skb structure. Also we drop the use of IEEE802154_ADDR_LEN which is
link-layer specific. Instead we using EUI64_ADDR_LEN which should always
the default case for now.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch adds a check if the dataroom of skb contains a dispatch value
by checking if skb->len != 0. This patch also change the dispatch
evaluation by the recently introduced helpers for checking the common
6LoWPAN dispatch values for IPv6 and IPHC header.

There was also a forgotten else branch which should drop the packet if
no matching dispatch is available.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch moves values for all lowpan interface to the shared
implementation of 6lowpan. This patch also quietly fixes the forgotten
IFF_NO_QUEUE flag for the bluetooth 6LoWPAN interface. An identically
commit is 4afbc0db ("net: 6lowpan: convert to using IFF_NO_QUEUE") which
wasn't changed for bluetooth 6lowpan.

All 6lowpan interfaces should be virtual with IFF_NO_QUEUE, using EUI64
address length, the mtu size is 1280 (IPV6_MIN_MTU) and the netdev type
is ARPHRD_6LOWPAN.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The chan_get() function just adds unnecessary indirection to calling
the chan_create() call. The only added value it gives is the chan->ops
assignment, but that can equally well be done in the calling code.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The typical convention when having both a child and a parent channel
variable is to call the former 'chan' and the latter 'pchan'. When
there's only one variable it's called chan. Rename the 'pchan'
variables in the 6lowpan code to follow this convention.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

All the chan_open() function now does is to call chan_create() so it
doesn't really add any value.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The L2CAP core code makes sure of setting the channel state to
BT_CONNECTED, so there's no need for the implementation code (6lowpan
in this case) to do it.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The L2CAP core code already sets the local MPS to a sane value. The
remote MPS value otoh comes from the remote side so there's no point
in trying to hard-code it to any value.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The omtu value is determined by the remote peer so there's no point in
trying to hard-code it to any value. The IPSP specification otoh gives
a more reasonable value for the imtu, i.e. 1280.
Signed-off-by: NJohan Hedberg <johan.hedberg@intel.com>
Acked-by: NJukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch introduced the 6lowpan netdev private data struct. We name it
lowpan_priv and it's placed at the beginning of netdev private data. All
lowpan interfaces should allocate this room at first of netdev private
data. 6LoWPAN LL private data can be allocate by additional netdev private
data, e.g. dev->priv_size should be "sizeof(struct lowpan_priv) +
sizeof(LL_LOWPAN_PRIVATE_DATA)".
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

The usually way to get the btle lowpan private data is to use the
introduced lowpan_dev inline function. This patch will cleanup by using
lowpan_dev consequently.
Reviewed-by: NStefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch fix a possible race after calling register_netdev. After
calling netdev_register it could be possible that netdev_ops callbacks
use the uninitialized private data of lowpan_dev. By moving the
initialization of this data before netdev_register we can be sure that
initialized private data is be used after netdev_register.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch removes the additional module_put() in disconnect_all_peers()
making a correct module refcount so that the module can be removed after
disabling 6lowpan through debugfs.
Signed-off-by: NLukasz Duda <lukasz.duda@nordicsemi.no>
Signed-off-by: NGlenn Ruben Bakke <glenn.ruben.bakke@nordicsemi.no>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch removes the kfree of the netdev priv in device_event() upon
NETDEV_UNREGISTER event. The freeing of memory is taken care of by the
netdev destructor.
Signed-off-by: NLukasz Duda <lukasz.duda@nordicsemi.no>
Signed-off-by: NGlenn Ruben Bakke <glenn.ruben.bakke@nordicsemi.no>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch moves the sysfs device used by the netdev from the device of
the first connected peer to the hci sysfs device. Using the sysfs device
of hci instead of the first connected device fixes this issue such that
the sysfs group of tx-0 and bt0 kobject are still present after the last
peer has been deleted and all sysfs entries can be removed.
Signed-off-by: NLukasz Duda <lukasz.duda@nordicsemi.no>
Signed-off-by: NGlenn Ruben Bakke <glenn.ruben.bakke@nordicsemi.no>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch renames the variable used to trigger scheduling of
delete_netdev. Changed to infinitiv in order to describe the action
to be done.
Signed-off-by: NLukasz Duda <lukasz.duda@nordicsemi.no>
Signed-off-by: NGlenn Ruben Bakke <glenn.ruben.bakke@nordicsemi.no>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch fixes an issue with the netdev not being unregistered when
the last peer is deleted. Removing the logical negation operator on the
boolean solves this issue. If the last peer is removed the condition
will be true, and the delete_netdev() is scheduled.
Signed-off-by: NLukasz Duda <lukasz.duda@nordicsemi.no>
Signed-off-by: NGlenn Ruben Bakke <glenn.ruben.bakke@nordicsemi.no>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>