Avoid race conditions when accessing the L2CAP socket from within the
timeout handlers.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When using DEFER_SETUP on a RFCOMM socket, a SABM frame triggers
authorization which when rejected send a DM response. This is fine
according to the RFCOMM spec:
the responding implementation may replace the "proper" response
on the Multiplexer Control channel with a DM frame, sent on the
referenced DLCI to indicate that the DLCI is not open, and that
the responder would not grant a request to open it later either.
But some stacks doesn't seems to cope with this leaving DLCI 0 open after
receiving DM frame.
To fix it properly a timer was introduced to rfcomm_session which is used
to set a timeout when the last active DLC of a session is unlinked, this
will give the remote stack some time to reply with a proper DISC frame on
DLCI 0 avoiding both sides sending DISC to each other on stacks that
follow the specification and taking care of those who don't by taking
down DLCI 0.
Signed-off-by: Luiz Augusto von Dentz <luiz.dentz@openbossa.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Support for receiving of SREJ frames as specified by the state table.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When L2CAP loses an I-frame we send a SREJ frame to the transmitter side
requesting the lost packet. This patch implement all Recv I-frame events
on SREJ_SENT state table except the ones that deal with SendRej (the REJ
exception at receiver side is yet not implemented).
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Implement CRC16 check for L2CAP packets. FCS is used by Streaming Mode and
Enhanced Retransmission Mode and is a extra check for the packet content.
Using CRC16 is the default, L2CAP won't use FCS only when both side send
a "No FCS" request.
Initially based on a patch from Nathan Holstein <nathan@lampreynetworks.com>
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Streaming Mode is helpful for the Bluetooth streaming based profiles, such
as A2DP. It doesn't have any error control or flow control.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
L2CAP uses retransmission and monitor timers to inquiry the other side
about unacked I-frames. After sending each I-frame we (re)start the
retransmission timer. If it expires, we start a monitor timer that send a
S-frame with P bit set and wait for S-frame with F bit set. If monitor
timer expires, try again, at a maximum of L2CAP_DEFAULT_MAX_TX.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When receiving an I-frame with unexpected txSeq, receiver side start the
recovery procedure by sending a REJ S-frame to the transmitter side. So
the transmitter can re-send the lost I-frame.
This patch just adds a basic support for retransmission, it doesn't
mean that ERTM now has full support for packet retransmission.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
ERTM should use Segmentation and Reassembly to break down a SDU in many
PDUs on sending data to the other side.
On sending packets we queue all 'segments' until end of segmentation and
just the add them to the queue for sending. On receiving we create a new
SKB with the SDU reassembled.
Initially based on a patch from Nathan Holstein <nathan@lampreynetworks.com>
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch adds support for ERTM transfers, without retransmission, with
txWindow up to 63 and with acknowledgement of packets received. Now the
packets are queued before call l2cap_do_send(), so packets couldn't be
sent at the time we call l2cap_sock_sendmsg(). They will be sent in
an asynchronous way on later calls of l2cap_ertm_send(). Besides if an
error occurs on calling l2cap_do_send() we disconnect the channel.
Initially based on a patch from Nathan Holstein <nathan@lampreynetworks.com>
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The code for sending a disconnect request was repeated several times
within L2CAP source code. So move this into its own function.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Add support to config_req and config_rsp to configure ERTM and Streaming
mode. If the remote device specifies ERTM or Streaming mode, then the
same mode is proposed. Otherwise ERTM or Basic mode is used. And in case
of a state 2 device, the remote device should propose the same mode. If
not, then the channel gets disconnected.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When trying to establish a connection with Enhanced Retransmission mode
enabled, the RFC option needs to be added to the configuration.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
To enable Enhanced Retransmission mode it needs to be set via a socket
option. A different mode can be set on a socket, but on listen() and
connect() the mode is checked and ERTM is only allowed if it is enabled
via the module parameter.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Since the Enhanced Retransmission mode for L2CAP is still under heavy
development disable it by default and provide a module option to enable
it manually for testing.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The rfcomm_init bug fix went into the kernel premature before it got fully
reviewed and acknowledged by the Bluetooth maintainer. So fix up the coding
style now.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
hdev->req_lock is used as mutex so make it a mutex.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The core exports the hci_conn_hold_device() and hci_conn_put_device()
functions for device reference of connections. Use this to ensure that
the uevents from the parent are send after the child ones.
Based on a report by Brian Rogers <brian@xyzw.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The device model itself has no real usable reference counting at the
moment and this causes problems if parents are deleted before their
children. The device model itself handles the memory details of this
correctly, but the uevent order is not consistent. This causes various
problems for systems like HAL or even X.
So until device_put() does a proper cleanup, the device for Bluetooth
connection will be protected with an extra reference counting to ensure
the correct order of uevents when connections are terminated.
This is not an automatic feature. Higher Bluetooth layers like HIDP or
BNEP should grab this new reference to ensure that their uevents are
send before the ones from the parent device.
Based on a report by Brian Rogers <brian@xyzw.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Currently the HID subsystem will create HIDRAW devices for the transport
driver, but it will not disconnect them. Until the HID subsytem gets
fixed, ensure that HIDRAW and HIDDEV devices are disconnected when the
Bluetooth HID device gets removed.
Based on a patch from Brian Rogers <brian@xyzw.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There is a test case in PTS tool; PTS will send the VIRTUAL_CABLE_UNPLUG
command to IUT. Then IUT should disconnect the channel and kill the HID
session when it receives the command. The VIRTUAL_CABLE_UNPLUG command
is parsed by HID transport, but it is not scheduled to do so. Add a
call to hidp_schedule() to kill the session.
Signed-off-by: Jothikumar Mothilal <jothikumar.mothilal@atheros.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The SCO sockets for Bluetooth audio setup and streaming are missing the
shutdown implementation. This hasn't been a problem so far, but with a
more deeper integration with PulseAudio it is important to shutdown SCO
sockets properly.
Also the Headset profile 1.2 has more detailed qualification tests that
require that SCO and RFCOMM channels are terminated in the right order. A
proper shutdown function is necessary for this.
Based on a report by Johan Hedberg <johan.hedberg@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Tested-by: Johan Hedberg <johan.hedberg@nokia.com>
String literals are constant, and usually, we can also tag the array
of pointers const too, moving it to the .rodata section.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
rfcomm tty may be used before rfcomm_tty_driver initilized,
The problem is that now socket layer init before tty layer, if userspace
program do socket callback right here then oops will happen.
reporting in:
http://marc.info/?l=linux-bluetooth&m=124404919324542&w=2
make 3 changes:
1. remove #ifdef in rfcomm/core.c,
make it blank function when rfcomm tty not selected in rfcomm.h
2. tune the rfcomm_init error patch to ensure
tty driver initilized before rfcomm socket usage.
3. remove __exit for rfcomm_cleanup_sockets
because above change need call it in a __init function.
Reported-by: Oliver Hartkopp <oliver@hartkopp.net>
Tested-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is the result of an automatic spatch transformation to convert
all ndo_start_xmit() return values of 0 to NETDEV_TX_OK.
Some occurences are missed by the automatic conversion, those will be
handled in a seperate patch.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit 2b85a34e91
(net: No more expensive sock_hold()/sock_put() on each tx)
changed initial sk_wmem_alloc value.
We need to take into account this offset when reporting
sk_wmem_alloc to user, in PROC_FS files or various
ioctls (SIOCOUTQ/TIOCOUTQ)
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since the re-write of the RFKILL subsystem it is no longer good to just
select RFKILL, but it is important to add a proper depends on rule.
Based on a report by Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
With the re-write of the RFKILL subsystem it is now possible to easily
integrate RFKILL soft-switch support into the Bluetooth subsystem. All
Bluetooth devices will now get automatically RFKILL support.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Bluetooth source uses some endian conversion helpers, that in the end
translate to kernel standard routines. So remove this obfuscation since it
is fully pointless.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This adds the basic constants required to add support for L2CAP Enhanced
Retransmission feature.
Based on a patch from Nathan Holstein <nathan@lampreynetworks.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This patch fixes the errors without changing the l2cap.o binary:
text data bss dec hex filename
18059 568 0 18627 48c3 l2cap.o.after
18059 568 0 18627 48c3 l2cap.o.before
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The initial value of err is not used until it is set to -ENOMEM. So just
remove the initialization completely.
Based on a patch from Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Using the L2CAP_CONF_HINT macro is easier to understand than using a
hardcoded 0x80 value.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Use macros instead of hardcoded numbers to make the L2CAP source code
more readable.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Change the name of the Kernel CAPI exported function capi_ctr_reseted()
to something representing its purpose better.
Impact: renaming, no functional change
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
The calls to flush_work() are pointless in a single thread workqueue
and they are actually causing a lockdep warning.
=============================================
[ INFO: possible recursive locking detected ]
2.6.30-rc6-02911-gbb803cf #16
---------------------------------------------
bluetooth/2518 is trying to acquire lock:
(bluetooth){+.+.+.}, at: [<c0130c14>] flush_work+0x28/0xb0
but task is already holding lock:
(bluetooth){+.+.+.}, at: [<c0130424>] worker_thread+0x149/0x25e
other info that might help us debug this:
2 locks held by bluetooth/2518:
#0: (bluetooth){+.+.+.}, at: [<c0130424>] worker_thread+0x149/0x25e
#1: (&conn->work_del){+.+...}, at: [<c0130424>] worker_thread+0x149/0x25e
stack backtrace:
Pid: 2518, comm: bluetooth Not tainted 2.6.30-rc6-02911-gbb803cf #16
Call Trace:
[<c03d64d9>] ? printk+0xf/0x11
[<c0140d96>] __lock_acquire+0x7ce/0xb1b
[<c0141173>] lock_acquire+0x90/0xad
[<c0130c14>] ? flush_work+0x28/0xb0
[<c0130c2e>] flush_work+0x42/0xb0
[<c0130c14>] ? flush_work+0x28/0xb0
[<f8b84966>] del_conn+0x1c/0x84 [bluetooth]
[<c0130469>] worker_thread+0x18e/0x25e
[<c0130424>] ? worker_thread+0x149/0x25e
[<f8b8494a>] ? del_conn+0x0/0x84 [bluetooth]
[<c0133843>] ? autoremove_wake_function+0x0/0x33
[<c01302db>] ? worker_thread+0x0/0x25e
[<c013355a>] kthread+0x45/0x6b
[<c0133515>] ? kthread+0x0/0x6b
[<c01034a7>] kernel_thread_helper+0x7/0x10
Based on a report by Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Tested-by: Oliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
A remote device in security mode 3 that tries to connect will require
the pairing during the connection setup phase. The disconnect timeout
is now triggered within 10 milliseconds and causes the pairing to fail.
If a connection is not fully established and a PIN code request is
received, don't trigger the disconnect timeout. The either successful
or failing connection complete event will make sure that the timeout
is triggered at the right time.
The biggest problem with security mode 3 is that many Bluetooth 2.0
device and before use a temporary security mode 3 for dedicated
bonding.
Based on a report by Johan Hedberg <johan.hedberg@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Tested-by: Johan Hedberg <johan.hedberg@nokia.com>
The connection setup phase takes around 2 seconds or longer and in
that time it is possible that the need for an ACL connection is no
longer present. If that happens then, the connection attempt will
be canceled.
This only applies to outgoing connections, but currently it can also
be triggered by incoming connection. Don't call hci_acl_connect_cancel()
on incoming connection since these have to be either accepted or rejected
in this state. Once they are successfully connected they need to be
fully disconnected anyway.
Also remove the wrong hci_acl_disconn() call for SCO and eSCO links
since at this stage they can't be disconnected either, because the
connection handle is still unknown.
Based on a report by Johan Hedberg <johan.hedberg@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Tested-by: Johan Hedberg <johan.hedberg@nokia.com>
The module refcount is increased by hci_dev_hold() call in hci_conn_add()
and decreased by hci_dev_put() call in del_conn(). In case the connection
setup fails, hci_dev_put() is never called.
Procedure to reproduce the issue:
# hciconfig hci0 up
# lsmod | grep btusb -> "used by" refcount = 1
# hcitool cc <non-exisiting bdaddr> -> will get timeout
# lsmod | grep btusb -> "used by" refcount = 2
# hciconfig hci0 down
# lsmod | grep btusb -> "used by" refcount = 1
# rmmod btusb -> ERROR: Module btusb is in use
The hci_dev_put() call got moved into del_conn() with the 2.6.25 kernel
to fix an issue with hci_dev going away before hci_conn. However that
change was wrong and introduced this problem.
When calling hci_conn_del() it has to call hci_dev_put() after freeing
the connection details. This handling should be fully symmetric. The
execution of del_conn() is done in a work queue and needs it own calls
to hci_dev_hold() and hci_dev_put() to ensure that the hci_dev stays
until the connection cleanup has been finished.
Based on a report by Bing Zhao <bzhao@marvell.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Tested-by: Bing Zhao <bzhao@marvell.com>
Due to a semantic changes in flush_workqueue() the current approach of
synchronizing the sysfs handling for connections doesn't work anymore. The
whole approach is actually fully broken and based on assumptions that are
no longer valid.
With the introduction of Simple Pairing support, the creation of low-level
ACL links got changed. This change invalidates the reason why in the past
two independent work queues have been used for adding/removing sysfs
devices. The adding of the actual sysfs device is now postponed until the
host controller successfully assigns an unique handle to that link. So
the real synchronization happens inside the controller and not the host.
The only left-over problem is that some internals of the sysfs device
handling are not initialized ahead of time. This leaves potential access
to invalid data and can cause various NULL pointer dereferences. To fix
this a new function makes sure that all sysfs details are initialized
when an connection attempt is made. The actual sysfs device is only
registered when the connection has been successfully established. To
avoid a race condition with the registration, the check if a device is
registered has been moved into the removal work.
As an extra protection two flush_work() calls are left in place to
make sure a previous add/del work has been completed first.
Based on a report by Marc Pignat <marc.pignat@hevs.ch>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Tested-by: Justin P. Mattock <justinmattock@gmail.com>
Tested-by: Roger Quadros <ext-roger.quadros@nokia.com>
Tested-by: Marc Pignat <marc.pignat@hevs.ch>
The Bluetooth 2.1 specification introduced four different security modes
that can be mapped using Legacy Pairing and Simple Pairing. With the
usage of Simple Pairing it is required that all connections (except
the ones for SDP) are encrypted. So even the low security requirement
mandates an encrypted connection when using Simple Pairing. When using
Legacy Pairing (for Bluetooth 2.0 devices and older) this is not required
since it causes interoperability issues.
To support this properly the low security requirement translates into
different host controller transactions depending if Simple Pairing is
supported or not. However in case of Simple Pairing the command to
switch on encryption after a successful authentication is not triggered
for the low security mode. This patch fixes this and actually makes
the logic to differentiate between Simple Pairing and Legacy Pairing
a lot simpler.
Based on a report by Ville Tervo <ville.tervo@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Bluetooth stack uses a reference counting for all established ACL
links and if no user (L2CAP connection) is present, the link will be
terminated to save power. The problem part is the dedicated pairing
when using Legacy Pairing (Bluetooth 2.0 and before). At that point
no user is present and pairing attempts will be disconnected within
10 seconds or less. In previous kernel version this was not a problem
since the disconnect timeout wasn't triggered on incoming connections
for the first time. However this caused issues with broken host stacks
that kept the connections around after dedicated pairing. When the
support for Simple Pairing got added, the link establishment procedure
needed to be changed and now causes issues when using Legacy Pairing
When using Simple Pairing it is possible to do a proper reference
counting of ACL link users. With Legacy Pairing this is not possible
since the specification is unclear in some areas and too many broken
Bluetooth devices have already been deployed. So instead of trying to
deal with all the broken devices, a special pairing timeout will be
introduced that increases the timeout to 60 seconds when pairing is
triggered.
If a broken devices now puts the stack into an unforeseen state, the
worst that happens is the disconnect timeout triggers after 120 seconds
instead of 4 seconds. This allows successful pairings with legacy and
broken devices now.
Based on a report by Johan Hedberg <johan.hedberg@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The Broadcom chips with 2.1 firmware handle the fallback case to a SCO
link wrongly when setting up eSCO connections.
< HCI Command: Setup Synchronous Connection (0x01|0x0028) plen 17
handle 11 voice setting 0x0060
> HCI Event: Command Status (0x0f) plen 4
Setup Synchronous Connection (0x01|0x0028) status 0x00 ncmd 1
> HCI Event: Connect Complete (0x03) plen 11
status 0x00 handle 1 bdaddr 00:1E:3A:xx:xx:xx type SCO encrypt 0x01
The Link Manager negotiates the fallback to SCO, but then sends out
a Connect Complete event. This is wrong and the Link Manager should
actually send a Synchronous Connection Complete event if the Setup
Synchronous Connection has been used. Only the remote side is allowed
to use Connect Complete to indicate the missing support for eSCO in
the host stack.
This patch adds a workaround for this which clearly should not be
needed, but reality is that broken Broadcom devices are deployed.
Based on a report by Ville Tervo <ville.tervo@nokia.com>
Signed-off-by: Marcel Holtman <marcel@holtmann.org>
Some Bluetooth chips (like the ones from Texas Instruments) don't do
proper eSCO negotiations inside the Link Manager. They just return an
error code and in case of the Kyocera ED-8800 headset it is just a
random error.
< HCI Command: Setup Synchronous Connection 0x01|0x0028) plen 17
handle 1 voice setting 0x0060
> HCI Event: Command Status (0x0f) plen 4
Setup Synchronous Connection (0x01|0x0028) status 0x00 ncmd 1
> HCI Event: Synchronous Connect Complete (0x2c) plen 17
status 0x1f handle 257 bdaddr 00:14:0A:xx:xx:xx type eSCO
Error: Unspecified Error
In these cases it is up to the host stack to fallback to a SCO setup
and so retry with SCO parameters.
Based on a report by Nick Pelly <npelly@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
There is a missing call to rfcomm_dlc_clear_timer in the case that
DEFER_SETUP is used and so the connection gets disconnected after the
timeout even if it was successfully accepted previously.
This patch adds a call to rfcomm_dlc_clear_timer to rfcomm_dlc_accept
which will get called when the user accepts the connection by calling
read() on the socket.
Signed-off-by: Johan Hedberg <johan.hedberg@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
struct tty_operations::proc_fops took it's place and there is one less
create_proc_read_entry() user now!
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
