And avoid decreasing the ack log twice when dequeueing connected LLCP
sockets.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Calling sock_orphan when e.g. the NFC adapter is removed can lead to
kernel crashes when e.g. a connection less client is sleeping on the
Rx workqueue, waiting for data to show up.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This is really difficult to test with real NFC devices, but without
this fix an LLCP server will eventually refuse new connections.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Safer and more robust than than memcpy_toiovec.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

We can cast msg_name to a sockaddr_nfc_llcp pointer directly.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Not only it was improperly use to queue backlogged RX skbuffs, but it was
also not processed at all.
If the socket receive queue is full we simply drop the incoming packets.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Set timestamp in sent and received sk_buffs. timestamp is then put in
msghdr structure in llcp_sock_recvmsg().
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This is easily triggerable when fuzz-testing as an unprivileged user.
We could rate-limit it, but given we don't print similar messages
for other protocols, I just removed it.
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It simply involves getting the client dsap and ssap and calling the UI
frame building and sending routine.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

With connection less PDUs we have to send the SSAP and DSAP as well.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Logical continuations should be on the previous line.
Signed-off-by: NSzymon Janc <szymon.janc@tieto.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Validation of userspace input shouldn't trigger dmesg spamming.
Signed-off-by: NDave Jones <davej@redhat.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This adds support for socket of type SOCK_RAW to LLCP.
sk_buff are copied and sent to raw sockets with a 2 bytes extra header:
The first byte header contains the nfc adapter index.
The second one contains flags:
- 0x01 - Direction (0=RX, 1=TX)
- 0x02-0x80 - Reserved
A raw socket has to be explicitly bound to a nfc adapter. This is achieved
by specifying the adapter index to be bound to in the dev_idx field of the
sockaddr_nfc_llcp struct passed to bind().
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This patch remove the repeated code for checking llcp_sock &
llcp_sock->dev against NULL.
Signed-off-by: NSyam Sidhardhan <s.syam@samsung.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

They both can potentially be NULL.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This patch fixes a typo and return the correct error when trying to
bind 2 sockets to the same service name.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The LLCP SAP should only be freed when the socket owning it is released.
As long as the socket is alive, the SAP should be reserved in order to
e.g. send the right wks array when bringing the MAC up.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Set the right target index and use a better socket declaration routine.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

llcp_sock_getname can be called without a device attached to the nfc_llcp_sock.

This would lead to the following BUG:

[  362.341807] BUG: unable to handle kernel NULL pointer dereference at           (null)
[  362.341815] IP: [<ffffffff836258e5>] llcp_sock_getname+0x75/0xc0
[  362.341818] PGD 31b35067 PUD 30631067 PMD 0
[  362.341821] Oops: 0000 [#627] PREEMPT SMP DEBUG_PAGEALLOC
[  362.341826] CPU 3
[  362.341827] Pid: 7816, comm: trinity-child55 Tainted: G      D W    3.5.0-rc4-next-20120628-sasha-00005-g9f23eb7 #479
[  362.341831] RIP: 0010:[<ffffffff836258e5>]  [<ffffffff836258e5>] llcp_sock_getname+0x75/0xc0
[  362.341832] RSP: 0018:ffff8800304fde88  EFLAGS: 00010286
[  362.341834] RAX: 0000000000000000 RBX: ffff880033cb8000 RCX: 0000000000000001
[  362.341835] RDX: ffff8800304fdec4 RSI: ffff8800304fdec8 RDI: ffff8800304fdeda
[  362.341836] RBP: ffff8800304fdea8 R08: 7ebcebcb772b7ffb R09: 5fbfcb9c35bdfd53
[  362.341838] R10: 4220020c54326244 R11: 0000000000000246 R12: ffff8800304fdec8
[  362.341839] R13: ffff8800304fdec4 R14: ffff8800304fdec8 R15: 0000000000000044
[  362.341841] FS:  00007effa376e700(0000) GS:ffff880035a00000(0000) knlGS:0000000000000000
[  362.341843] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  362.341844] CR2: 0000000000000000 CR3: 0000000030438000 CR4: 00000000000406e0
[  362.341851] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  362.341856] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[  362.341858] Process trinity-child55 (pid: 7816, threadinfo ffff8800304fc000, task ffff880031270000)
[  362.341858] Stack:
[  362.341862]  ffff8800304fdea8 ffff880035156780 0000000000000000 0000000000001000
[  362.341865]  ffff8800304fdf78 ffffffff83183b40 00000000304fdec8 0000006000000000
[  362.341868]  ffff8800304f0027 ffffffff83729649 ffff8800304fdee8 ffff8800304fdf48
[  362.341869] Call Trace:
[  362.341874]  [<ffffffff83183b40>] sys_getpeername+0xa0/0x110
[  362.341877]  [<ffffffff83729649>] ? _raw_spin_unlock_irq+0x59/0x80
[  362.341882]  [<ffffffff810f342b>] ? do_setitimer+0x23b/0x290
[  362.341886]  [<ffffffff81985ede>] ? trace_hardirqs_on_thunk+0x3a/0x3f
[  362.341889]  [<ffffffff8372a539>] system_call_fastpath+0x16/0x1b
[  362.341921] Code: 84 00 00 00 00 00 b8 b3 ff ff ff 48 85 db 74 54 66 41 c7 04 24 27 00 49 8d 7c 24 12 41 c7 45 00 60 00 00 00 48 8b 83 28 05 00 00 <8b> 00 41 89 44 24 04 0f b6 83 41 05 00 00 41 88 44 24 10 0f b6
[  362.341924] RIP  [<ffffffff836258e5>] llcp_sock_getname+0x75/0xc0
[  362.341925]  RSP <ffff8800304fde88>
[  362.341926] CR2: 0000000000000000
[  362.341928] ---[ end trace 6d450e935ee18bf3 ]---
Signed-off-by: NSasha Levin <levinsasha928@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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>