This was triggered by turning off encryption on ACL link when rfcomm
was using high security. rfcomm_security_cfm (which is called from rx
task) was closing DLC and this involves sending disconnect message
(and locking socket).

Move closing DLC to rfcomm_process_dlcs and only flag DLC for closure
in rfcomm_security_cfm.

BUG: sleeping function called from invalid context at net/core/sock.c:2032
in_atomic(): 1, irqs_disabled(): 0, pid: 1788, name: kworker/0:3
[<c0068a08>] (unwind_backtrace+0x0/0x108) from [<c05e25dc>] (dump_stack+0x20/0x24)
[<c05e25dc>] (dump_stack+0x20/0x24) from [<c0087ba8>] (__might_sleep+0x110/0x12c)
[<c0087ba8>] (__might_sleep+0x110/0x12c) from [<c04801d8>] (lock_sock_nested+0x2c/0x64)
[<c04801d8>] (lock_sock_nested+0x2c/0x64) from [<c05670c8>] (l2cap_sock_sendmsg+0x58/0xcc)
[<c05670c8>] (l2cap_sock_sendmsg+0x58/0xcc) from [<c047cf6c>] (sock_sendmsg+0xb0/0xd0)
[<c047cf6c>] (sock_sendmsg+0xb0/0xd0) from [<c047cfc8>] (kernel_sendmsg+0x3c/0x44)
[<c047cfc8>] (kernel_sendmsg+0x3c/0x44) from [<c056b0e8>] (rfcomm_send_frame+0x50/0x58)
[<c056b0e8>] (rfcomm_send_frame+0x50/0x58) from [<c056b168>] (rfcomm_send_disc+0x78/0x80)
[<c056b168>] (rfcomm_send_disc+0x78/0x80) from [<c056b9f4>] (__rfcomm_dlc_close+0x2d0/0x2fc)
[<c056b9f4>] (__rfcomm_dlc_close+0x2d0/0x2fc) from [<c056bbac>] (rfcomm_security_cfm+0x140/0x1e0)
[<c056bbac>] (rfcomm_security_cfm+0x140/0x1e0) from [<c0555ec0>] (hci_event_packet+0x1ce8/0x4d84)
[<c0555ec0>] (hci_event_packet+0x1ce8/0x4d84) from [<c0550380>] (hci_rx_task+0x1d0/0x2d0)
[<c0550380>] (hci_rx_task+0x1d0/0x2d0) from [<c009ee04>] (tasklet_action+0x138/0x1e4)
[<c009ee04>] (tasklet_action+0x138/0x1e4) from [<c009f21c>] (__do_softirq+0xcc/0x274)
[<c009f21c>] (__do_softirq+0xcc/0x274) from [<c009f6c0>] (do_softirq+0x60/0x6c)
[<c009f6c0>] (do_softirq+0x60/0x6c) from [<c009f794>] (local_bh_enable_ip+0xc8/0xd4)
[<c009f794>] (local_bh_enable_ip+0xc8/0xd4) from [<c05e5804>] (_raw_spin_unlock_bh+0x48/0x4c)
[<c05e5804>] (_raw_spin_unlock_bh+0x48/0x4c) from [<c040d470>] (data_from_chip+0xf4/0xaec)
[<c040d470>] (data_from_chip+0xf4/0xaec) from [<c04136c0>] (send_skb_to_core+0x40/0x178)
[<c04136c0>] (send_skb_to_core+0x40/0x178) from [<c04139f4>] (cg2900_hu_receive+0x15c/0x2d0)
[<c04139f4>] (cg2900_hu_receive+0x15c/0x2d0) from [<c0414cb8>] (hci_uart_tty_receive+0x74/0xa0)
[<c0414cb8>] (hci_uart_tty_receive+0x74/0xa0) from [<c02cbd9c>] (flush_to_ldisc+0x188/0x198)
[<c02cbd9c>] (flush_to_ldisc+0x188/0x198) from [<c00b2774>] (process_one_work+0x144/0x4b8)
[<c00b2774>] (process_one_work+0x144/0x4b8) from [<c00b2e8c>] (worker_thread+0x198/0x468)
[<c00b2e8c>] (worker_thread+0x198/0x468) from [<c00b9bc8>] (kthread+0x98/0xa0)
[<c00b9bc8>] (kthread+0x98/0xa0) from [<c0061744>] (kernel_thread_exit+0x0/0x8)
Signed-off-by: NSzymon Janc <szymon.janc@tieto.com>
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>

Fix lines longer than 80 chars in length.
Signed-off-by: NWaldemar Rymarkiewicz <waldemar.rymarkiewicz@tieto.com>
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>

Remove extra spaces from legal text so that legal stuff looks
the same for all bluetooth code.
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@nokia.com>
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>

Remove extra spaces, assignments in if statement, zeroing static
variables, extra braces. Fix includes.
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@nokia.com>
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>

Remove dead code and unused rfcomm thread events
Signed-off-by: NAndrei Emeltchenko <andrei.emeltchenko@nokia.com>
Acked-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>

To make net/ and include/net/ code consistent use __packed instead of
__attribute__ ((packed)). Bluetooth subsystem was one of the last net
subsys still using __attribute__ ((packed)).
Signed-off-by: NGustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: NMarcel 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: NLuiz Augusto von Dentz <luiz.dentz@openbossa.org>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

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: NOliver Hartkopp <oliver@hartkopp.net>
Tested-by: NOliver Hartkopp <oliver@hartkopp.net>
Signed-off-by: NDave Young <hidave.darkstar@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

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: NMarcel Holtmann <marcel@holtmann.org>

Change the RFCOMM internals to use the new security levels and remove
the link mode details.
Signed-off-by: NMarcel 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: NMarcel Holtmann <marcel@holtmann.org>

When switching a RFCOMM socket to a TTY, the remote modem status might
be needed later. Currently it is lost since the original configuration
is done via the socket interface. So store the modem status and reply
it when the socket has been converted to a TTY.
Signed-off-by: NDenis Kenzior <denis.kenzior@trolltech.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Recent tests with various Bluetooth headsets have shown that some of
them don't enforce authentication and encryption when connecting. All
of them leave it up to the host stack to enforce it. Non of them should
allow unencrypted connections, but that is how it is. So in case the
link mode settings require authentication and/or encryption it will now
also be enforced on outgoing RFCOMM connections. Previously this was
only done for incoming connections.

This support has a small drawback from a protocol level point of view
since the host stack can't really tell with 100% certainty if a remote
side is already authenticated or not. So if both sides are configured
to enforce authentication it will be requested twice. Most Bluetooth
chips are caching this information and thus no extra authentication
procedure has to be triggered over-the-air, but it can happen.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

X86_32 was the last user of the FASTCALL macro, now that it
uses regparm(3) by default, this macro expands to nothing.
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch changes the RFCOMM TTY release process so that the TTY is kept
on the list until it is really freed. A new device flag is used to keep
track of released TTYs.
Signed-off-by: NVille Tervo <ville.tervo@nokia.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch reduces the default L2CAP MTU for all RFCOMM connections
from 1024 to 1013 to improve the interoperability with some broken
RFCOMM implementations. To make this more flexible the L2CAP MTU
becomes also a module parameter and so it can changed at runtime.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

This patch removes all relics of the /proc usage from the Bluetooth
subsystem core and its upper layers. All the previous information are
now available via /sys/class/bluetooth through appropriate functions.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch moves rfcomm_crc_table[] into the RFCOMM core, because there
is no need to keep it in a separate file.
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

 - added typedef unsigned int __nocast gfp_t;

 - replaced __nocast uses for gfp flags with gfp_t - it gives exactly
   the same warnings as far as sparse is concerned, doesn't change
   generated code (from gcc point of view we replaced unsigned int with
   typedef) and documents what's going on far better.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch fixes the sparse warnings "implicit cast to nocast type"
for the priority or gfp_mask parameters of the memory allocations.
Signed-off-by: NVictor Fusco <victor@cetuc.puc-rio.br>
Signed-off-by: NDomen Puncer <domen@coderock.org>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements the remote port negotiation (RPN) of the RFCOMM
protocol for Bluetooth.
Signed-off-by: NJ. Suter <jsuter@hardwave.de>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!