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>
dpm_list currently relies on the fact that child devices will
be registered after their parents to get a correct suspend
order. Using device_move() however destroys this assumption, as
an already registered device may be moved under a newly registered
one.
This patch adds a new argument to device_move(), allowing callers
to specify how dpm_list should be adapted.
Signed-off-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Userspace pairing code can be simplified if it doesn't have to fall
back to using L2CAP_LM in the case of L2CAP raw sockets. This patch
allows the BT_SECURITY socket option to be used for these sockets.
Signed-off-by: Johan Hedberg <johan.hedberg@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The CID value of L2CAP sockets need to be set to zero. All userspace
applications do this via memset() on the sockaddr_l2 structure. The
RFCOMM implementation uses in-kernel L2CAP sockets and so it has to
make sure that l2_cid is set to zero.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In the future the L2CAP layer will have full support for fixed channels
and right now it already can export the channel assignment, but for the
functions bind() and connect() the usage of only CID 0 is allowed. This
allows an easy detection if the kernel supports fixed channels or not,
because otherwise it would impossible for application to tell.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When BT_DEFER_SETUP is enabled on a RFCOMM socket, then switch its
current state from BT_OPEN to BT_CONNECT2. This gives the Bluetooth
core a unified way to handle L2CAP and RFCOMM sockets. The BT_CONNECT2
state is designated for incoming connections.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When BT_DEFER_SETUP has been enabled on a Bluetooth socket it keeps
signaling POLLIN all the time. This is a wrong behavior. The POLLIN
should only be signaled if the client socket is in BT_CONNECT2 state
and the parent has been BT_DEFER_SETUP enabled.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The authentication requirement got only updated when the security level
increased. This is a wrong behavior. The authentication requirement is
read by the Bluetooth daemon to make proper decisions when handling the
IO capabilities exchange. So set the value that is currently expected by
the higher layers like L2CAP and RFCOMM.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The L2CAP layer can trigger the authentication via an ACL connection or
later on to increase the security level. When increasing the security
level it didn't use the same authentication requirements when triggering
a new ACL connection. Make sure that exactly the same authentication
requirements are used. The only exception here are the L2CAP raw sockets
which are only used for dedicated bonding.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Some of the qualification tests demand that in case of failures in L2CAP
the HCI disconnect should indicate a reason why L2CAP fails. This is a
bluntly layer violation since multiple L2CAP connections could be using
the same ACL and thus forcing a disconnect reason is not a good idea.
To comply with the Bluetooth test specification, the disconnect reason
is now stored in the L2CAP connection structure and every time a new
L2CAP channel is added it will set back to its default. So only in the
case where the L2CAP channel with the disconnect reason is really the
last one, it will propagated to the HCI layer.
The HCI layer has been extended with a disconnect indication that allows
it to ask upper layers for a disconnect reason. The upper layer must not
support this callback and in that case it will nicely default to the
existing behavior. If an upper layer like L2CAP can provide a disconnect
reason that one will be used to disconnect the ACL or SCO link.
No modification to the ACL disconnect timeout have been made. So in case
of Linux to Linux connection the initiator will disconnect the ACL link
before the acceptor side can signal the specific disconnect reason. That
is perfectly fine since Linux doesn't make use of this value anyway. The
L2CAP layer has a perfect valid error code for rejecting connection due
to a security violation. It is unclear why the Bluetooth specification
insists on having specific HCI disconnect reason.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In preparation for L2CAP fixed channel support, the CID value of a
L2CAP connection needs to be accessible via the socket interface. The
CID is the connection identifier and exists as source and destination
value. So extend the L2CAP socket address structure with this field and
change getsockname() and getpeername() to fill it in.
The bind() and connect() functions have been modified to handle L2CAP
socket address structures of variable sizes. This makes them future
proof if additional fields need to be added.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If the extended features mask indicates support for fixed channels,
request the list of available fixed channels. This also enables the
fixed channel features bit so remote implementations can request
information about it. Currently only the signal channel will be
listed.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The recommendation for the L2CAP PSM 1 (SDP) is to not use any kind
of authentication or encryption. So don't trigger authentication
for incoming and outgoing SDP connections.
For L2CAP PSM 3 (RFCOMM) there is no clear requirement, but with
Bluetooth 2.1 the initiator is required to enable authentication
and encryption first and this gets enforced. So there is no need
to trigger an additional authentication step. The RFCOMM service
security will make sure that a secure enough link key is present.
When the encryption gets enabled after the SDP connection setup,
then switch the security level from SDP to low security.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
If the remote L2CAP server uses authentication pending stage and
encryption is enabled it can happen that a L2CAP connection request is
sent twice due to a race condition in the connection state machine.
When the remote side indicates any kind of connection pending, then
track this state and skip sending of L2CAP commands for this period.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When two L2CAP connections are requested quickly after the ACL link has
been established there exists a window for a race condition where a
connection request is sent before the information response has been
received. Any connection request should only be sent after an exchange
of the extended features mask has been finished.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When no authentication requirements are selected, but an outgoing or
incoming connection has requested any kind of security enforcement,
then set these authentication requirements.
This ensures that the userspace always gets informed about the
authentication requirements (if available). Only when no security
enforcement has happened, the kernel will signal invalid requirements.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When receiving incoming connection to specific services, always use
general bonding. This ensures that the link key gets stored and can be
used for further authentications.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When attempting to setup eSCO connections it can happen that some link
manager implementations fail to properly negotiate the eSCO parameters
and thus fail the eSCO setup. Normally the link manager is responsible
for the negotiation of the parameters and actually fallback to SCO if
no agreement can be reached. In cases where the link manager is just too
stupid, then at least try to establish a SCO link if eSCO fails.
For the Bluetooth devices with EDR support this includes handling packet
types of EDR basebands. This is particular tricky since for the EDR the
logic of enabling/disabling one specific packet type is turned around.
This fix contains an extra bitmask to disable eSCO EDR packet when
trying to fallback to a SCO connection.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
For L2CAP sockets with medium and high security requirement a missing
encryption will enforce the closing of the link. For the L2CAP raw
sockets this is not needed, so skip that check.
This fixes a crash when pairing Bluetooth 2.0 (and earlier) devices
since the L2CAP state machine got confused and then locked up the whole
system.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
During a role change with pre-Bluetooth 2.1 devices, the remote side drops
the encryption of the RFCOMM connection. We allow a grace period for the
encryption to be re-established, before dropping the connection. During
this grace period, the RFCOMM_SEC_PENDING flag is set. Check this flag
before sending RFCOMM packets.
Signed-off-by: Jaikumar Ganesh <jaikumar@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Due to lockdep changes, the CONFIG_DEBUG_LOCK_ALLOC ifdef is not needed
now. So just remove it here.
The following commit fixed the !lockdep build warnings:
commit e8f6fbf62d
Author: Ingo Molnar <mingo@elte.hu>
Date: Wed Nov 12 01:38:36 2008 +0000
lockdep: include/linux/lockdep.h - fix warning in net/bluetooth/af_bluetooth.c
Signed-off-by: Dave Young <hidave.darkstar@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
With the support for the enhanced security model and the support for
deferring connection setup, it is a good idea to increase various
version numbers.
This is purely cosmetic and has no effect on the behavior, but can
be really helpful when debugging problems in different kernel versions.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The new socket options should only be evaluated for SOL_BLUETOOTH level
and not for every other level. Previously this causes some minor issues
when detecting if a kernel with certain features is available.
Also restrict BT_SECURITY to SOCK_SEQPACKET for L2CAP and SOCK_STREAM for
the RFCOMM protocol.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
For L2CAP connections with high security setting, the link will be
immediately dropped when the encryption gets disabled. For L2CAP
connections with medium security there will be grace period where
the remote device has the chance to re-enable encryption. If it
doesn't happen then the link will also be disconnected.
The requirement for the grace period with medium security comes from
Bluetooth 2.0 and earlier devices that require role switching.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
A role switch with devices following the Bluetooth pre-2.1 standards
or without Encryption Pause and Resume support is not possible if
encryption is enabled. Most newer headsets require the role switch,
but also require that the connection is encrypted.
For connections with a high security mode setting, the link will be
immediately dropped. When the connection uses medium security mode
setting, then a grace period is introduced where the TX is halted and
the remote device gets a change to re-enable encryption after the
role switch. If not re-enabled the link will be dropped.
Based on initial work by Ville Tervo <ville.tervo@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The current security model is based around the flags AUTH, ENCRYPT and
SECURE. Starting with support for the Bluetooth 2.1 specification this is
no longer sufficient. The different security levels are now defined as
SDP, LOW, MEDIUM and SECURE.
Previously it was possible to set each security independently, but this
actually doesn't make a lot of sense. For Bluetooth the encryption depends
on a previous successful authentication. Also you can only update your
existing link key if you successfully created at least one before. And of
course the update of link keys without having proper encryption in place
is a security issue.
The new security levels from the Bluetooth 2.1 specification are now
used internally. All old settings are mapped to the new values and this
way it ensures that old applications still work. The only limitation
is that it is no longer possible to set authentication without also
enabling encryption. No application should have done this anyway since
this is actually a security issue. Without encryption the integrity of
the authentication can't be guaranteed.
As default for a new L2CAP or RFCOMM connection, the LOW security level
is used. The only exception here are the service discovery sessions on
PSM 1 where SDP level is used. To have similar security strength as with
a Bluetooth 2.0 and before combination key, the MEDIUM level should be
used. This is according to the Bluetooth specification. The MEDIUM level
will not require any kind of man-in-the-middle (MITM) protection. Only
the HIGH security level will require this.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When the remote device supports only SCO connections, on receipt of
the HCI_EV_CONN_COMPLETE event packet, the connect state is changed to
BT_CONNECTED, but the socket state is not updated. Hence, the connect()
call times out even though the SCO connection has been successfully
established.
Based on a report by Jaikumar Ganesh <jaikumar@google.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
All SCO and eSCO connection are auto-accepted no matter if there is a
corresponding listening socket for them. This patch changes this and
connection requests for SCO and eSCO without any socket are rejected.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In order to decide if listening L2CAP sockets should be accept()ed
the BD_ADDR of the remote device needs to be known. This patch adds
a socket option which defines a timeout for deferring the actual
connection setup.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In order to decide if listening RFCOMM sockets should be accept()ed
the BD_ADDR of the remote device needs to be known. This patch adds
a socket option which defines a timeout for deferring the actual
connection setup.
The connection setup is done after reading from the socket for the
first time. Until then writing to the socket returns ENOTCONN.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The L2CAP and RFCOMM applications require support for authorization
and the ability of rejecting incoming connection requests. The socket
interface is not really able to support this.
This patch does the ground work for a socket option to defer connection
setup. Setting this option allows calling of accept() and then the
first read() will trigger the final connection setup. Calling close()
would reject the connection.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The socket option levels SOL_L2CAP, SOL_RFOMM and SOL_SCO are currently
in use by various Bluetooth applications. Going forward the common
option level SOL_BLUETOOTH should be used. This patch prepares the clean
split of the old and new option levels while keeping everything backward
compatibility.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
In case of connection failures the rfcomm_sock_sendmsg() should return
an error and not a 0 value.
Signed-off-by: Victor Shcherbatyuk <victor.shcherbatyuk@tomtom.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
