The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This reuse the L2CAP MTU auto logic to select the MTU used for RFCOMM
channels, this should increase the maximum from 1013 to 1021 when 3-DH5
is supported.
Since it does not set an L2CAP MTU we no longer need a debugfs so that
is removed.
Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
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.
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: Marcel Holtmann <marcel@holtmann.org>
The RFCOMM_PSM constant is actually a duplicate. So remove it and
use the L2CAP_PSM_RFCOMM constant instead.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Enabling CONFIG_DEBUG_ATOMIC_SLEEP has shown that some rfcomm functions
acquiring spinlocks call sleeping locks further in the chain. Converting
the offending spinlocks into mutexes makes sleeping safe.
Signed-off-by: Libor Pechacek <lpechacek@suse.cz>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
The tty driver api design prefers no-fail writes if the driver
write_room() method has previously indicated space is available
to accept writes. Since this is trivially possible for the
RFCOMM tty driver, do so.
Introduce rfcomm_dlc_send_noerror(), which queues but does not
schedule the krfcomm thread if the dlc is not yet connected
(and thus does not error based on the connection state).
The mtu size test is also unnecessary since the caller already
chunks the written data into mtu size.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Only one session/channel combination may be in use at any one
time. However, the failure does not occur until the tty is
opened (in rfcomm_dlc_open()).
Because these settings are actually bound at rfcomm device
creation (via RFCOMMCREATEDEV ioctl), validate and fail before
creating the rfcomm tty device.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
When RFCOMM_RELEASE_ONHUP is set, the rfcomm tty driver 'takes over'
the initial rfcomm_dev reference created by the RFCOMMCREATEDEV ioctl.
The assumption is that the rfcomm tty driver will release the
rfcomm_dev reference when the tty is freed (in rfcomm_tty_cleanup()).
However, if the tty is never opened, the 'take over' never occurs,
so when RFCOMMRELEASEDEV ioctl is called, the reference is not
released.
Track the state of the reference 'take over' so that the release
is guaranteed by either the RFCOMMRELEASEDEV ioctl or the rfcomm tty
driver.
Note that the synchronous hangup in rfcomm_release_dev() ensures
that rfcomm_tty_install() cannot race with the RFCOMMRELEASEDEV ioctl.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
No logic prevents an rfcomm_dev from being released multiple
times. For example, if the rfcomm_dev ref count is large due
to pending tx, then multiple RFCOMMRELEASEDEV ioctls may
mistakenly release the rfcomm_dev too many times. Note that
concurrent ioctls are not required to create this condition.
Introduce RFCOMM_DEV_RELEASED status bit which guarantees the
rfcomm_dev can only be released once.
NB: Since the flags are exported to userspace, introduce the status
field to track state for which userspace should not be aware.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
With the introduction of security level 4, the RFCOMM sockets need to
be made aware of this new level. This change ensures that the pairing
requirements are set correctly for these connections.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
The address information of RFCOMM sockets should be stored in its
own socket structure. Trying to generalize them is not helpful since
different transports have different address types.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
There are a mix of function prototypes with and without extern
in the kernel sources. Standardize on not using extern for
function prototypes.
Function prototypes don't need to be written with extern.
extern is assumed by the compiler. Its use is as unnecessary as
using auto to declare automatic/local variables in a block.
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Previous commits have improved the handling of the RFCOMM session
timer and the RFCOMM session pointers such that freed RFCOMM
session structures should no longer be erroneously accessed. The
RFCOMM session refcnt now has no purpose and will be deleted by
this commit.
Note that the RFCOMM session is now deleted as soon as the
RFCOMM control channel link is no longer required. This makes the
lifetime of the RFCOMM session deterministic and absolute.
Previously with the refcnt, there was uncertainty about when
the session structure would be deleted because the relative
refcnt prevented the session structure from being deleted at will.
It was noted that the refcnt could malfunction under very heavy
real-time processor loading in embedded SMP environments. This
could cause premature RFCOMM session deletion or double session
deletion that could result in kernel crashes. Removal of the
refcnt prevents this issue.
There are 4 connection / disconnection RFCOMM session scenarios:
host initiated control link ---> host disconnected control link
host initiated ctrl link ---> remote device disconnected ctrl link
remote device initiated ctrl link ---> host disconnected ctrl link
remote device initiated ctrl link ---> remote device disc'ed ctrl link
The control channel connection procedures are independent of the
disconnection procedures. Strangely, the RFCOMM session refcnt was
applying special treatment so erroneously combining connection and
disconnection events. This commit fixes this issue by removing
some session code that used the "initiator" member of the session
structure that was intended for use with the data channels.
Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Unfortunately, the design retains local copies of the s RFCOMM
session pointer in various code blocks and this invites the erroneous
access to a freed RFCOMM session structure.
Therefore, return the RFCOMM session pointer back up the call stack
to avoid accessing a freed RFCOMM session structure. When the RFCOMM
session is deleted, NULL is passed up the call stack.
If active DLCs exist when the rfcomm session is terminating,
avoid a memory leak of rfcomm_dlc structures by ensuring that
rfcomm_session_close() is used instead of rfcomm_session_del().
Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
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: Szymon Janc <szymon.janc@tieto.com>
Signed-off-by: Gustavo 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: Andrei Emeltchenko <andrei.emeltchenko@nokia.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Remove extra spaces, assignments in if statement, zeroing static
variables, extra braces. Fix includes.
Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@nokia.com>
Signed-off-by: Gustavo 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: Gustavo F. Padovan <padovan@profusion.mobi>
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>
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>
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>
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>
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: Denis Kenzior <denis.kenzior@trolltech.com>
Signed-off-by: Marcel 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: Marcel 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: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David 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: Ville Tervo <ville.tervo@nokia.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
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: Marcel 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: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David 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: Marcel 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: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus 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: Victor Fusco <victor@cetuc.puc-rio.br>
Signed-off-by: Domen Puncer <domen@coderock.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements the remote port negotiation (RPN) of the RFCOMM
protocol for Bluetooth.
Signed-off-by: J. Suter <jsuter@hardwave.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: David 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!
Gustavo A. R. Silva
Luiz Augusto von Dentz
Elena Reshetova
Marcel Holtmann
Libor Pechacek
Peter Hurley
John W. Linville
Joe Perches
Dean Jenkins
Szymon Janc
Waldemar Rymarkiewicz
Andrei Emeltchenko
Gustavo F. Padovan
Luiz Augusto von Dentz
Dave Young
Harvey Harrison
Ville Tervo
Al Viro
Al Viro
Victor Fusco
J. Suter
Linus Torvalds