Commit 835a6a2f8603 ("Bluetooth: Stop sabotaging list poisoning")
thought that the code was sabotaging the list poisoning when NULL'ing
out the list pointers and removed it.

But what was going on was that the bluetooth code was using NULL
pointers for the list as a way to mark it empty, and that commit just
broke it (and replaced the test with NULL with a "list_empty()" test on
a uninitialized list instead, breaking things even further).

So fix it all up to use the regular and real list_empty() handling
(which does not use NULL, but a pointer to itself), also making sure to
initialize the list properly (the previous NULL case was initialized
implicitly by the session being allocated with kzalloc())

This is a combination of patches by Marcel Holtmann and Tedd Ho-Jeong
An.

[ I would normally expect to get this through the bt tree, but I'm going
  to release -rc1, so I'm just committing this directly   - Linus ]

Reported-and-tested-by: Jörg Otte <jrg.otte@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Original-by: Tedd Ho-Jeong An <tedd.an@intel.com>
Original-by: Marcel Holtmann <marcel@holtmann.org>:
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

In preparation for changing how struct net is refcounted
on kernel sockets pass the knowledge that we are creating
a kernel socket from sock_create_kern through to sk_alloc.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

While it is not used by newer userspace anymore, the older userspace was
utilizing HIDP_VIRTUAL_CABLE_UNPLUG and HIDP_BOOT_PROTOCOL_MODE flags
when adding a new HIDP connection.

The flags validation is important, but we can not break older userspace
and with that allow providing these flags even if newer userspace does
not use them anymore.

Reported-and-tested-by: Jörg Otte <jrg.otte@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

The HIDP flags should be clearly restricted to valid ones. So this puts
extra checks in place to ensure this.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

it's OK after we'd verified the sockets, but not before that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

use memdup_user for rd_data import.

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

The current kernel options do not make it clear which modules are for
Bluetooth Classic (BR/EDR) and which are for Bluetooth Low Energy (LE).

To make it really clear, introduce BT_BREDR and BT_LE options with
proper dependencies into the different modules. Both new options
default to y to not create a regression with previous kernel config
files.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

It's natural to have *_get() functions that increment the reference
count of an object to return the object type itself. This way it's
simple to make a copy of the object pointer and increase the reference
count in a single step. This patch updates two such get() functions,
namely hci_conn_get() and l2cap_conn_get(), and updates the users to
take advantage of the new API.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

The new leds bit handling produces this spares warning.

  CHECK   net/bluetooth/hidp/core.c
net/bluetooth/hidp/core.c:156:60: warning: dubious: x | !y

Just fix it by doing an explicit x << 0 shift operation.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>