Commit Graph

289 Commits

Author SHA1 Message Date
Vignesh Raman
32333edb82 Bluetooth: Avoid use of session socket after the session gets freed
The commits 08c30aca9e "Bluetooth: Remove
RFCOMM session refcnt" and 8ff52f7d04
"Bluetooth: Return RFCOMM session ptrs to avoid freed session"
allow rfcomm_recv_ua and rfcomm_session_close to delete the session
(and free the corresponding socket) and propagate NULL session pointer
to the upper callers.

Additional fix is required to terminate the loop in rfcomm_process_rx
function to avoid use of freed 'sk' memory.

The issue is only reproducible with kernel option CONFIG_PAGE_POISONING
enabled making freed memory being changed and filled up with fixed char
value used to unmask use-after-free issues.

Signed-off-by: Vignesh Raman <Vignesh_Raman@mentor.com>
Signed-off-by: Vitaly Kuzmichev <Vitaly_Kuzmichev@mentor.com>
Acked-by: Dean Jenkins <Dean_Jenkins@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org
2014-07-22 16:07:31 +02:00
Johan Hedberg
e7cafc4525 Bluetooth: Pass initiator/acceptor information to hci_conn_security()
We're interested in whether an authentication request is because of a
remote or local action. So far hci_conn_security() has been used both
for incoming and outgoing actions (e.g. RFCOMM or L2CAP connect
requests) so without some modifications it cannot know which peer is
responsible for requesting authentication.

This patch adds a new "bool initiator" parameter to hci_conn_security()
to indicate which side is responsible for the request and updates the
current users to pass this information correspondingly.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-07-17 14:39:39 +02:00
Vladimir Davydov
093facf363 Bluetooth: never linger on process exit
If the current process is exiting, lingering on socket close will make
it unkillable, so we should avoid it.

Reproducer:

  #include <sys/types.h>
  #include <sys/socket.h>

  #define BTPROTO_L2CAP   0
  #define BTPROTO_SCO     2
  #define BTPROTO_RFCOMM  3

  int main()
  {
          int fd;
          struct linger ling;

          fd = socket(PF_BLUETOOTH, SOCK_STREAM, BTPROTO_RFCOMM);
          //or: fd = socket(PF_BLUETOOTH, SOCK_DGRAM, BTPROTO_L2CAP);
          //or: fd = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_SCO);

          ling.l_onoff = 1;
          ling.l_linger = 1000000000;
          setsockopt(fd, SOL_SOCKET, SO_LINGER, &ling, sizeof(ling));

          return 0;
  }

Signed-off-by: Vladimir Davydov <vdavydov@parallels.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: stable@vger.kernel.org
2014-07-17 12:13:06 +02:00
John W. Linville
a5eb1aeb25 Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next
Conflicts:
	drivers/bluetooth/btusb.c
2014-05-29 13:03:47 -04:00
Libor Pechacek
86aae6c7b5 Bluetooth: Convert RFCOMM spinlocks into mutexes
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>
2014-05-05 19:25:06 -07:00
David S. Miller
676d23690f net: Fix use after free by removing length arg from sk_data_ready callbacks.
Several spots in the kernel perform a sequence like:

	skb_queue_tail(&sk->s_receive_queue, skb);
	sk->sk_data_ready(sk, skb->len);

But at the moment we place the SKB onto the socket receive queue it
can be consumed and freed up.  So this skb->len access is potentially
to freed up memory.

Furthermore, the skb->len can be modified by the consumer so it is
possible that the value isn't accurate.

And finally, no actual implementation of this callback actually uses
the length argument.  And since nobody actually cared about it's
value, lots of call sites pass arbitrary values in such as '0' and
even '1'.

So just remove the length argument from the callback, that way there
is no confusion whatsoever and all of these use-after-free cases get
fixed as a side effect.

Based upon a patch by Eric Dumazet and his suggestion to audit this
issue tree-wide.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-11 16:15:36 -04:00
Johan Hedberg
e8b1ab9e6d Bluetooth: Fix returning peer address in pending connect state
We should let user space request the peer address also in the pending
connect states, i.e. BT_CONNECT and BT_CONNECT2. There is existing user
space code that tries to do this and will fail without extending the set
of allowed states for the peer address information.

This patch adds the two states to the allowed ones in the L2CAP and
RFCOMM sock_getname functions, thereby preventing ENOTCONN from being
returned.

Reported-by: Andrzej Kaczmarek <andrzej.kaczmarek@tieto.com>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Tested-by: Andrzej Kaczmarek <andrzej.kaczmarek@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-03-26 09:31:33 -07:00
Joe Perches
dcf4adbfdc Bluetooth: Convert uses of __constant_<foo> to <foo>
The use of __constant_<foo> has been unnecessary for quite awhile now.

Make these uses consistent with the rest of the kernel.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-03-12 11:10:17 -07:00
Andrzej Kaczmarek
b1765e7afe Bluetooth: Fix channel check when binding RFCOMM sock
When binding RFCOMM socket with non-zero channel we're checking if
there is already any other socket which has the same channel number
assigned and then fail. This check does not consider situation where
we have another socket connected to remote device on given channel
number in which case we still should be able to bind local socket.

This patch changes __rfcomm_get_sock_by_addr() to return only sockets
in either BT_BOUND or BT_LISTEN states, also name is updated to better
describe what this function does now.

Signed-off-by: Andrzej Kaczmarek <andrzej.kaczmarek@tieto.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-20 11:34:08 -08:00
Peter Hurley
8981be9b2f Bluetooth: Fix write_room() calculation
The skb truesize of a 12-byte payload with a 10-byte head/tail
reserve is 768 bytes. Consequently, even with 40 tx_credits, at
most 6 packets could be queued at any one time:

  40 tx_credits * 127-byte mtu < 768-byte truesize * 7

This error could also cause the tx queue to apparently stall if
credit flow control is disabled (where tx_credits is fixed at 5),
or if the receiver only granted a limited number of tx credits
(eg., less than 7).

Instead, track the outstanding number of queued packets not yet sent
in wmem_alloc and allow for a maximum of 40 queued packets. Report
the space avail for a single write() as the mtu * number of packets
left before reaching the maximum.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:32 -08:00
Peter Hurley
b16b435131 Bluetooth: Refactor write_room() calculation
Compute the amount of space available for a single write()
within rfcomm_room(); clamp to 0 for negative values. Note
this patch does not change the result of the computation.

Report the amount of room returned in the debug printk.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:32 -08:00
Peter Hurley
72e5108c6d Bluetooth: Don't fail RFCOMM tty writes
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>
2014-02-14 13:39:32 -08:00
Peter Hurley
5326a4ee98 Bluetooth: Force -EIO from tty read/write if .activate() fails
If rfcomm_dlc_open() fails, set tty into error state which returns
-EIO from reads and writes.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:32 -08:00
Peter Hurley
fb856e5090 Bluetooth: Cleanup RFCOMM device registration error handling
If RFCOMM tty device registration fails, cleanup by releasing
the tty_port reference to trigger rfcomm_dev destruction
(rather than open-coding it).

The dlc reference release is moved into rfcomm_dev_add(),
which ensures cleanup in both error paths -- ie., if
__rfcomm_dev_add() fails or if tty_port_register_device() fails.

Fixes releasing the module reference if device registration fails.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:32 -08:00
Peter Hurley
f355095756 Bluetooth: Refactor rfcomm_dev_add()
Move rfcomm_dev allocation and initialization into new function,
__rfcomm_dev_add(), to simplify resource release in error handling.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:31 -08:00
Peter Hurley
033ace99c4 Bluetooth: Serialize RFCOMMCREATEDEV and RFCOMMRELEASEDEV ioctls
At least two different race conditions exist with multiple concurrent
RFCOMMCREATEDEV and RFCOMMRELEASEDEV ioctls:
* Multiple concurrent RFCOMMCREATEDEVs with RFCOMM_REUSE_DLC can
  mistakenly share the same DLC.
* RFCOMMRELEASEDEV can destruct the rfcomm_dev still being
  constructed by RFCOMMCREATEDEV.

Introduce rfcomm_ioctl_mutex to serialize these add/remove operations.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:31 -08:00
Peter Hurley
7611fcedd6 Bluetooth: Rename __rfcomm_dev_get() to __rfcomm_dev_lookup()
Functions which search lists for matching id's are more
commonly named *_lookup, which is the convention in the
bluetooth core as well.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:31 -08:00
Peter Hurley
b4d21f1939 Bluetooth: Fix RFCOMM parent device for reused dlc
The RFCOMM tty device is parented to the acl link device when
the dlc state_change(BT_CONNECTED) notification is received.
However, if the dlc from the RFCOMM socket is being reused
(RFCOMM_REUSE_DLC is set), then the dlc may already be connected,
and no notification will occur.

Instead, always parent the RFCOMM tty device to the acl link
device at registration time. If the acl link device is not available
(eg, because the dlc is not connected) then the tty will remain
unparented until the BT_CONNECTED notification is received.

Fixes regression with ModemManager when the rfcomm device is
created with the flag RFCOMM_REUSE_DLC.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:31 -08:00
Peter Hurley
b92483d54a Bluetooth: Fix unsafe RFCOMM device parenting
Accessing the results of hci_conn_hash_lookup_ba() is unsafe without
holding the hci_dev_lock() during the lookup. For example:

CPU 0                             | CPU 1
hci_conn_hash_lookup_ba           | hci_conn_del
  rcu_read_lock                   |   hci_conn_hash_del
  list_for_each_entry_rcu         |     list_del_rcu
    if (.....)                    |       synchronize_rcu
      rcu_read_unlock             |
                                  |   hci_conn_del_sysfs
                                  |   hci_dev_put
                                  |   hci_conn_put
                                  |     put_device (last reference)
                                  |       bt_link_release
                                  |         kfree(conn)
      return p  << just freed     |

Even if a hci_conn reference were taken (via hci_conn_get), would
not guarantee the lifetime of the sysfs device, but only safe
access to the in-memory structure.

Ensure the hci_conn device stays valid while the rfcomm device
is reparented; rename rfcomm_get_device() to rfcomm_reparent_device()
and perform the reparenting within the function while holding the
hci_dev_lock.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:31 -08:00
Peter Hurley
c4fd318d6e Bluetooth: Directly close dlc for not yet started RFCOMM session
If the RFCOMM session has not yet been started (ie., session is
still in BT_BOUND state) when a dlc is closed, directly close and
unlink the dlc rather than sending a DISC frame that is never
sent.

This allows the dlci to be immediately reused rather than waiting
for a 20 second timeout.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:31 -08:00
Peter Hurley
f622357a5e Bluetooth: Refactor dlc disconnect logic in rfcomm_dlc_close()
Prepare for directly closing dlc if the RFCOMM session has not
yet been started; refactor the dlc disconnect logic into a separate
local function, __rfcomm_dlc_disconn(). Retains functional
equivalence.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:30 -08:00
Peter Hurley
5998e04063 Bluetooth: Refactor deferred setup test in rfcomm_dlc_close()
Prepare for directly closing dlc if the RFCOMM session has not
yet been started; refactor the deferred setup test for only those
dlc states to which the test applies. Retains functional
equivalence.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:30 -08:00
Peter Hurley
4339c25afb Bluetooth: Simplify RFCOMM session state eval
Merge conditional test for BT_LISTEN session state into following
switch statement (which is functionally equivalent).

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:30 -08:00
Peter Hurley
c10a848cea Bluetooth: Verify dlci not in use before rfcomm_dev create
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>
2014-02-14 13:39:30 -08:00
Peter Hurley
c949c224cf Bluetooth: Fix RFCOMM tty teardown race
RFCOMM tty device teardown can race with new tty device registration
for the same device id:

CPU 0                           | CPU 1
rfcomm_dev_add                  | rfcomm_dev_destruct
                                |   spin_lock
                                |   list_del   <== dev_id no longer used
                                |   spin_unlock
  spin_lock                     |     .
  [search rfcomm_dev_list]      |     .
  [dev_id not in use]           |     .
  [initialize new rfcomm_dev]   |     .
  spin_unlock                   |     .
                                |     .
  tty_port_register_device      |   tty_unregister_device

Don't remove rfcomm_dev from the device list until after tty device
unregistration has completed.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:30 -08:00
Peter Hurley
80ea73378a Bluetooth: Fix unreleased rfcomm_dev reference
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>
2014-02-14 13:39:29 -08:00
Peter Hurley
1c64834e06 Bluetooth: Release rfcomm_dev only once
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>
2014-02-14 13:39:29 -08:00
Peter Hurley
960603a54a Bluetooth: Exclude released devices from RFCOMMGETDEVLIST ioctl
When enumerating RFCOMM devices in the rfcomm_dev_list, holding
the rfcomm_dev_lock only guarantees the existence of the enumerated
rfcomm_dev in memory, and not safe access to its state. Testing
the device state (such as RFCOMM_TTY_RELEASED) does not guarantee
the device will remain in that state for the subsequent access
to the rfcomm_dev's fields, nor guarantee that teardown has not
commenced.

Obtain an rfcomm_dev reference for the duration of rfcomm_dev
access.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:29 -08:00
Peter Hurley
082a1532fc Bluetooth: Fix racy acquire of rfcomm_dev reference
rfcomm_dev_get() can return a rfcomm_dev reference for a
device for which destruction may be commencing. This can happen
on tty destruction, which calls rfcomm_tty_cleanup(), the last
port reference may have been released but RFCOMM_TTY_RELEASED
was not set. The following race is also possible:

CPU 0                            | CPU 1
                                 | rfcomm_release_dev
rfcomm_dev_get                   |   .
  spin_lock                      |   .
    dev  = __rfcomm_dev_get      |   .
    if dev                       |   .
      if test_bit(TTY_RELEASED)  |   .
                                 |   !test_and_set_bit(TTY_RELEASED)
                                 |     tty_port_put   <<<< last reference
      else                       |
        tty_port_get             |

The reference acquire is bogus because destruction will commence
with the release of the last reference.

Ignore the external state change of TTY_RELEASED and instead rely
on the reference acquire itself to determine if the reference is
valid.

Cc: Jiri Slaby <jslaby@suse.cz>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:29 -08:00
Peter Hurley
f87c24e74e Revert "Bluetooth: Move rfcomm_get_device() before rfcomm_dev_activate()"
This reverts commit e228b63390.

This is the third of a 3-patch revert, together with
Revert "Bluetooth: Remove rfcomm_carrier_raised()" and
Revert "Bluetooth: Always wait for a connection on RFCOMM open()".

Commit 4a2fb3ecc7,
"Bluetooth: Always wait for a connection on RFCOMM open()" open-codes
blocking on tty open(), rather than using the default behavior
implemented by the tty port.

The reasons for reverting that patch are detailed in that changelog;
this patch restores required functionality for that revert.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:29 -08:00
Peter Hurley
136c373bf0 Revert "Bluetooth: Always wait for a connection on RFCOMM open()"
This reverts commit 4a2fb3ecc7.

This is the second of a 3-patch revert, together with
Revert "Bluetooth: Remove rfcomm_carrier_raised()" and
Revert "Bluetooth: Move rfcomm_get_device() before rfcomm_dev_activate()".

Before commit cad348a17e,
  Bluetooth: Implement .activate, .shutdown and .carrier_raised methods,
tty_port_block_til_ready() was open-coded in rfcomm_tty_install() as
part of the RFCOMM tty open().

Unfortunately, it did not implement non-blocking open nor CLOCAL open,
but rather always blocked for carrier. This is not the expected or
typical behavior for ttys, and prevents several common terminal
programming idioms from working (eg., opening in non-blocking
mode to initialize desired termios settings then re-opening for
connection).

Commit cad348a17e,
  Bluetooth: Implement .activate, .shutdown and .carrier_raised methods,
added the necessary tty_port methods to use the default tty_port_open().
However, this triggered two important user-space regressions.

The first regression involves the complicated mechanism for reparenting
the rfcomm tty device to the ACL link device which represents an
open link to a specific bluetooth host. This regression causes ModemManager
to conclude the rfcomm tty device does not front a modem so it makes
no attempt to initialize an attached modem. This regression is
caused by the lack of a device_move() if the dlc is already open (and
not specifically related to the open-coded block_til_ready()).

A more appropriate solution is submitted in
"Bluetooth: Fix unsafe RFCOMM device parenting" and
"Bluetooth: Fix RFCOMM parent device for reused dlc"

The second regression involves "rfcomm bind" and wvdial (a ppp dialer).
rfcomm bind creates a device node for a /dev/rfcomm<n>. wvdial opens
that device in non-blocking mode (because it expects the connection
to have already been established). In addition, subsequent writes
to the rfcomm tty device fail (because the link is not yet connected;
rfcomm connection begins with the actual tty open()).

However, restoring the original behavior (in the patch which
this reverts) was undesirable.

Firstly, the original reporter notes that a trivial userspace
"workaround" already exists: rfcomm connect, which creates the
device node and establishes the expected connection.

Secondly, the failed writes occur because the rfcomm tty driver
does not buffer writes to an unconnected device; this contrasts with
the dozen of other tty drivers (in fact, all of them) that do just
that. The submitted patch "Bluetooth: Don't fail RFCOMM tty writes"
corrects this.

Thirdly, it was a long-standing bug to block on non-blocking open,
which is re-fixed by revert.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:29 -08:00
Peter Hurley
7f717b91dd Revert "Bluetooth: Remove rfcomm_carrier_raised()"
This reverts commit f86772af6a.

This is the first of a 3-patch revert, together with
Revert "Bluetooth: Always wait for a connection on RFCOMM open()" and
Revert "Bluetooth: Move rfcomm_get_device() before rfcomm_dev_activate()".

Commit 4a2fb3ecc7,
"Bluetooth: Always wait for a connection on RFCOMM open()" open-codes
blocking on tty open(), rather than using the default behavior
implemented by the tty port.

The reasons for reverting that patch are detailed in that changelog;
this patch restores required functionality for that revert.

Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Tested-By: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-14 13:39:28 -08:00
Johan Hedberg
35364c99d2 Bluetooth: Refuse peer RFCOMM address reading when not connected
When we're not connected the peer address information is undefined. This
patch fixes the remote address getting to return a proper error in case
the sate is anything else than BT_CONNECTED.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-02-13 09:51:39 +02:00
Marcel Holtmann
2c068e0b92 Bluetooth: Handle security level 4 for RFCOMM connections
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>
2014-02-13 09:51:35 +02:00
Gianluca Anzolin
f86772af6a Bluetooth: Remove rfcomm_carrier_raised()
Remove the rfcomm_carrier_raised() definition as that function isn't
used anymore.

Signed-off-by: Gianluca Anzolin <gianluca@sottospazio.it>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-01-06 13:51:45 -08:00
Gianluca Anzolin
4a2fb3ecc7 Bluetooth: Always wait for a connection on RFCOMM open()
This patch fixes two regressions introduced with the recent rfcomm tty
rework.

The current code uses the carrier_raised() method to wait for the
bluetooth connection when a process opens the tty.

However processes may open the port with the O_NONBLOCK flag or set the
CLOCAL termios flag: in these cases the open() syscall returns
immediately without waiting for the bluetooth connection to
complete.

This behaviour confuses userspace which expects an established bluetooth
connection.

The patch restores the old behaviour by waiting for the connection in
rfcomm_dev_activate() and removes carrier_raised() from the tty_port ops.

As a side effect the new code also fixes the case in which the rfcomm
tty device is created with the flag RFCOMM_REUSE_DLC: the old code
didn't call device_move() and ModemManager skipped the detection
probe. Now device_move() is always called inside rfcomm_dev_activate().

Signed-off-by: Gianluca Anzolin <gianluca@sottospazio.it>
Reported-by: Andrey Vihrov <andrey.vihrov@gmail.com>
Reported-by: Beson Chow <blc+bluez@mail.vanade.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-01-06 13:51:45 -08:00
Gianluca Anzolin
e228b63390 Bluetooth: Move rfcomm_get_device() before rfcomm_dev_activate()
This is a preparatory patch which moves the rfcomm_get_device()
definition before rfcomm_dev_activate() where it will be used.

Signed-off-by: Gianluca Anzolin <gianluca@sottospazio.it>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-01-06 13:51:45 -08:00
Gianluca Anzolin
5b89924187 Bluetooth: Release RFCOMM port when the last user closes the TTY
This patch fixes a userspace regression introduced by the commit
29cd718b.

If the rfcomm device was created with the flag RFCOMM_RELEASE_ONHUP the
user space expects that the tty_port is released as soon as the last
process closes the tty.

The current code attempts to release the port in the function
rfcomm_dev_state_change(). However it won't get a reference to the
relevant tty to send a HUP: at that point the tty is already destroyed
and therefore NULL.

This patch fixes the regression by taking over the tty refcount in the
tty install method(). This way the tty_port is automatically released as
soon as the tty is destroyed.

As a consequence the check for RFCOMM_RELEASE_ONHUP flag in the hangup()
method is now redundant. Instead we have to be careful with the reference
counting in the rfcomm_release_dev() function.

Signed-off-by: Gianluca Anzolin <gianluca@sottospazio.it>
Reported-by: Alexander Holler <holler@ahsoftware.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2014-01-06 13:51:45 -08:00
John W. Linville
7acd71879c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless into for-davem 2013-11-21 10:26:17 -05:00
Hannes Frederic Sowa
f3d3342602 net: rework recvmsg handler msg_name and msg_namelen logic
This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.

This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.

Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.

Also document these changes in include/linux/net.h as suggested by David
Miller.

Changes since RFC:

Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.

With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
	msg->msg_name = NULL
".

This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.

Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.

Cc: David Miller <davem@davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-20 21:52:30 -05:00
John W. Linville
32019c739c Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth 2013-11-15 14:18:45 -05:00
Seung-Woo Kim
8992da0993 Bluetooth: Fix to set proper bdaddr_type for RFCOMM connect
L2CAP socket validates proper bdaddr_type for connect, so this
patch fixes to set explictly bdaddr_type for RFCOMM connect.

Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2013-11-13 11:36:53 -02:00
Seung-Woo Kim
c507f138fc Bluetooth: Fix RFCOMM bind fail for L2CAP sock
L2CAP socket bind checks its bdaddr type but RFCOMM kernel thread
does not assign proper bdaddr type for L2CAP sock. This can cause
that RFCOMM failure.

Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2013-11-13 11:36:53 -02:00
Marcel Holtmann
60c7a3c9c7 Bluetooth: Fix issue with RFCOMM getsockopt operation
The commit 94a86df010 seem to have
uncovered a long standing bug that did not trigger so far.

BUG: unable to handle kernel paging request at 00000009dd503502
IP: [<ffffffff815b1868>] rfcomm_sock_getsockopt+0x128/0x200
PGD 0
Oops: 0000 [#1] SMP
Modules linked in: ath5k ath mac80211 cfg80211
CPU: 2 PID: 1459 Comm: bluetoothd Not tainted 3.11.0-133163-gcebd830 #2
Hardware name: System manufacturer System Product Name/P6T DELUXE V2, BIOS
1202    12/22/2010
task: ffff8803304106a0 ti: ffff88033046a000 task.ti: ffff88033046a000
RIP: 0010:[<ffffffff815b1868>]  [<ffffffff815b1868>]
rfcomm_sock_getsockopt+0x128/0x200
RSP: 0018:ffff88033046bed8  EFLAGS: 00010246
RAX: 00000009dd503502 RBX: 0000000000000003 RCX: 00007fffa2ed5548
RDX: 0000000000000003 RSI: 0000000000000012 RDI: ffff88032fd37480
RBP: ffff88033046bf28 R08: 00007fffa2ed554c R09: ffff88032f5707d8
R10: 00007fffa2ed5548 R11: 0000000000000202 R12: ffff880330bbd000
R13: 00007fffa2ed5548 R14: 0000000000000003 R15: 00007fffa2ed554c
FS:  00007fc44cfac700(0000) GS:ffff88033fc80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000009dd503502 CR3: 00000003304c2000 CR4: 00000000000007e0
Stack:
ffff88033046bf28 ffffffff815b0f2f ffff88033046bf18 0002ffff81105ef6
0000000600000000 ffff88032fd37480 0000000000000012 00007fffa2ed5548
0000000000000003 00007fffa2ed554c ffff88033046bf78 ffffffff814c0380
Call Trace:
[<ffffffff815b0f2f>] ? rfcomm_sock_setsockopt+0x5f/0x190
[<ffffffff814c0380>] SyS_getsockopt+0x60/0xb0
[<ffffffff815e0852>] system_call_fastpath+0x16/0x1b
Code: 02 00 00 00 0f 47 d0 4c 89 ef e8 74 13 cd ff 83 f8 01 19 c9 f7 d1 83 e1
f2 e9 4b ff ff ff 0f 1f 44 00 00 49 8b 84 24 70 02 00 00 <4c> 8b 30 4c 89 c0 e8
2d 19 cd ff 85 c0 49 89 d7 b9 f2 ff ff ff
RIP  [<ffffffff815b1868>] rfcomm_sock_getsockopt+0x128/0x200
RSP <ffff88033046bed8>
CR2: 00000009dd503502

It triggers in the following segment of the code:

0x1313 is in rfcomm_sock_getsockopt (net/bluetooth/rfcomm/sock.c:743).
738
739	static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __user *optval, int __user *optlen)
740	{
741		struct sock *sk = sock->sk;
742		struct rfcomm_conninfo cinfo;
743		struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
744		int len, err = 0;
745		u32 opt;
746
747		BT_DBG("sk %p", sk);

The l2cap_pi(sk) is wrong here since it should have been rfcomm_pi(sk),
but that socket of course does not contain the low-level connection
details requested here.

Tracking down the actual offending commit, it seems that this has been
introduced when doing some L2CAP refactoring:

commit 8c1d787be4
Author: Gustavo F. Padovan <padovan@profusion.mobi>
Date:   Wed Apr 13 20:23:55 2011 -0300

@@ -743,6 +743,7 @@ static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __u
        struct sock *sk = sock->sk;
        struct sock *l2cap_sk;
        struct rfcomm_conninfo cinfo;
+       struct l2cap_conn *conn = l2cap_pi(sk)->chan->conn;
        int len, err = 0;
        u32 opt;

@@ -787,8 +788,8 @@ static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __u

                l2cap_sk = rfcomm_pi(sk)->dlc->session->sock->sk;

-               cinfo.hci_handle = l2cap_pi(l2cap_sk)->conn->hcon->handle;
-               memcpy(cinfo.dev_class, l2cap_pi(l2cap_sk)->conn->hcon->dev_class, 3);
+               cinfo.hci_handle = conn->hcon->handle;
+               memcpy(cinfo.dev_class, conn->hcon->dev_class, 3);

The l2cap_sk got accidentally mixed into the sk (which is RFCOMM) and
now causing a problem within getsocketopt() system call. To fix this,
just re-introduce l2cap_sk and make sure the right socket is used for
the low-level connection details.

Reported-by: Fabio Rossi <rossi.f@inwind.it>
Reported-by: Janusz Dziedzic <janusz.dziedzic@gmail.com>
Tested-by: Janusz Dziedzic <janusz.dziedzic@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2013-11-13 11:36:52 -02:00
Marcel Holtmann
1120e4bfa5 Bluetooth: Use IS_ERR_OR_NULL for checking bt_debugfs
Make sure to use IS_ERR_OR_NULL for checking the existing of the root
debugfs dentry bt_debugfs.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2013-10-18 10:45:19 +03:00
Marcel Holtmann
94a86df010 Bluetooth: Store RFCOMM address information in its own socket structure
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>
2013-10-13 21:11:23 +03:00
Marcel Holtmann
24bc10cad3 Bluetooth: Access RFCOMM session addresses through L2CAP channel
The L2CAP socket structure does not contain the address information
anymore. They need to be accessed through the L2CAP channel.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
2013-10-13 20:00:28 +03:00
Gustavo Padovan
1025c04cec Merge git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth
Conflicts:
	net/bluetooth/hci_core.c
2013-09-27 11:56:14 -03:00
Gianluca Anzolin
29cd718beb Bluetooth: don't release the port in rfcomm_dev_state_change()
When the dlc is closed, rfcomm_dev_state_change() tries to release the
port in the case it cannot get a reference to the tty. However this is
racy and not even needed.

Infact as Peter Hurley points out:

1. Only consider dlcs that are 'stolen' from a connected socket, ie.
   reused. Allocated dlcs cannot have been closed prior to port
   activate and so for these dlcs a tty reference will always be avail
   in rfcomm_dev_state_change() -- except for the conditions covered by
   #2b below.
2. If a tty was at some point previously created for this rfcomm, then
   either
   (a) the tty reference is still avail, so rfcomm_dev_state_change()
       will perform a hangup. So nothing to do, or,
   (b) the tty reference is no longer avail, and the tty_port will be
       destroyed by the last tty_port_put() in rfcomm_tty_cleanup.
       Again, no action required.
3. Prior to obtaining the dlc lock in rfcomm_dev_add(),
   rfcomm_dev_state_change() will not 'see' a rfcomm_dev so nothing to
   do here.
4. After releasing the dlc lock in rfcomm_dev_add(),
   rfcomm_dev_state_change() will 'see' an incomplete rfcomm_dev if a
   tty reference could not be obtained. Again, the best thing to do here
   is nothing. Any future attempted open() will block on
   rfcomm_dev_carrier_raised(). The unconnected device will exist until
   released by ioctl(RFCOMMRELEASEDEV).

The patch removes the aforementioned code and uses the
tty_port_tty_hangup() helper to hangup the tty.

Signed-off-by: Gianluca Anzolin <gianluca@sottospazio.it>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2013-09-20 14:17:54 -05:00
Johan Hedberg
e793dcf082 Bluetooth: Fix waiting for clearing of BT_SK_SUSPEND flag
In the case of blocking sockets we should not proceed with sendmsg() if
the socket has the BT_SK_SUSPEND flag set. So far the code was only
ensuring that POLLOUT doesn't get set for non-blocking sockets using
poll() but there was no code in place to ensure that blocking sockets do
the right thing when writing to them.

This patch adds a new bt_sock_wait_ready helper function to sleep in the
sendmsg call if the BT_SK_SUSPEND flag is set, and wake up as soon as it
is unset. It also updates the L2CAP and RFCOMM sendmsg callbacks to take
advantage of this new helper function.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2013-09-18 17:02:59 -05:00