llcp_sock_getname() might get called before the LLCP socket was created.
This condition isn't checked, and llcp_sock_getname will simply deref a
NULL ptr in that case.

This exists starting with d646960f ("NFC: Initial LLCP support").
Signed-off-by: NSasha Levin <levinsasha928@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The MIU extension value can be received during the PAX or during the
connection establishment process. It's definitely a connection related value
rather than a link one.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

RW can only be fetched from a CONNECT or a CC frame thus making it an
end points specific value, not a link one.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Simplify the LLCP sockets structure by putting all the connected ones
into a single linked list.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

LLCP sockets point to their local LLCP service, so they need to take a
reference on it.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Fix the poll mask depending on the socket state. POLLOUT was missing
for example.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Blocking sockets should sleep on a CC (Connection Complete) reception
from the connect() call.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The socket local pointer needs to be set to NULL when the adapter is
removed or the MAC goes down.
If the socket release code is called after such an event, the socket
reference count still needs to be decreased in order for the socket to
eventually be freed.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The parent socket (the bound one) could be freed before its children, so
we should unlink the children without trying to reach it through the parent.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch is an initial implementation for the NFC Logical Link Control
protocol. It's also known as NFC peer to peer mode.
This is a basic implementation as it lacks SDP (services Discovery
Protocol), frames aggregation support, and frame rejecion parsing.
Follow up patches will implement those missing features.
This code has been tested against a Nexus S phone implementing LLCP 1.0.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>