When we receive a RNR, the remote is busy processing the last received
frame. We set a local flag for that, and we should send a SYMM when it
is set instead of sending any pending frame.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

In nfc_llcp_tx_work() the sk_buff is not freed when the llcp_sock
is null and the PDU is an I one.
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This patch keeps the socket alive and therefore does not remove
it from the sockets list in the local until the DISC PDU has been
actually sent. Otherwise we would reply with DM PDUs before sending
the DISC one.
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

And stop making it optional. LLCP is a fundamental part of the NFC
specifications and making it optional does not make much sense.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

According to the LLCP specs, we must terminate the LLCP link when receiving
a DISC with both ssap and dsap set to 0.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

local_cleanup is always called with device set to false as it means the
local LLCP is going away. So no need to pass this switch as an argument.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

When the MAC goes down, connected and connection less sockets should be
notified, but raw sockets should be kept alive.
They will get notified only when the physical devices goes away.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This resets remote parameters in both local and socket llcp structures when the
link goes down. That way, nfc_llcp_getsockopt won't return values corresponding
to the previous link parameters.
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This adds support for AGF PDUs. For each PDU contained in the AGF, a new sk_buff
is allocated and dispatched to its corresponding handler.
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

kfree_skb was called twice when the socket receive queue is full
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
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>

If the remote LLC doesn't reply in time to our SNL requests we remove
them from the list of pending requests. The timeout is fixed to an
arbitrary value of 3 times remote_lto.

When not replied, the local LLC broadcasts NFC_EVENT_LLC_SDRES nl events for
the concerned uris with sap values set to LLCP_SDP_UNBOUND (which is 65).
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This adds a netlink interface for service name lookup support.
Multiple URIs can be passed nested into the NFC_ATTR_LLC_SDP attribute
using the NFC_CMD_LLC_SDREQ netlink command.
When the SNL reply is received, a NFC_EVENT_LLC_SDRES event is sent to
the user space. URI and SAP tuples are passed back, nested into
NFC_ATTR_LLC_SDP attribute.
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

This modifies the way SDRES PDUs are sent back. If multiple SDREQs are
received within a single SNL PDU, all SDRES replies are sent packed in
one SNL PDU too.
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

We already have a pr_debug for that.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

If the socket link options are set, use them before the local one.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

They really are remote peer parameters, and we need to distinguish them
from the local ones as we'll modify the latter with socket options.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Whenever an adapter is removed we must clean all the local structures,
especially the timers and scheduled work. Otherwise those asynchronous
threads will eventually try to access the freed nfc_dev pointer if an LLCP
link is up.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

I'm not sure why, but the hlist for each entry iterators were conceived

        list_for_each_entry(pos, head, member)

The hlist ones were greedy and wanted an extra parameter:

        hlist_for_each_entry(tpos, pos, head, member)

Why did they need an extra pos parameter? I'm not quite sure. Not only
they don't really need it, it also prevents the iterator from looking
exactly like the list iterator, which is unfortunate.

Besides the semantic patch, there was some manual work required:

 - Fix up the actual hlist iterators in linux/list.h
 - Fix up the declaration of other iterators based on the hlist ones.
 - A very small amount of places were using the 'node' parameter, this
 was modified to use 'obj->member' instead.
 - Coccinelle didn't handle the hlist_for_each_entry_safe iterator
 properly, so those had to be fixed up manually.

The semantic patch which is mostly the work of Peter Senna Tschudin is here:

@@
iterator name hlist_for_each_entry, hlist_for_each_entry_continue, hlist_for_each_entry_from, hlist_for_each_entry_rcu, hlist_for_each_entry_rcu_bh, hlist_for_each_entry_continue_rcu_bh, for_each_busy_worker, ax25_uid_for_each, ax25_for_each, inet_bind_bucket_for_each, sctp_for_each_hentry, sk_for_each, sk_for_each_rcu, sk_for_each_from, sk_for_each_safe, sk_for_each_bound, hlist_for_each_entry_safe, hlist_for_each_entry_continue_rcu, nr_neigh_for_each, nr_neigh_for_each_safe, nr_node_for_each, nr_node_for_each_safe, for_each_gfn_indirect_valid_sp, for_each_gfn_sp, for_each_host;

type T;
expression a,c,d,e;
identifier b;
statement S;
@@

-T b;
    <+... when != b
(
hlist_for_each_entry(a,
- b,
c, d) S
|
hlist_for_each_entry_continue(a,
- b,
c) S
|
hlist_for_each_entry_from(a,
- b,
c) S
|
hlist_for_each_entry_rcu(a,
- b,
c, d) S
|
hlist_for_each_entry_rcu_bh(a,
- b,
c, d) S
|
hlist_for_each_entry_continue_rcu_bh(a,
- b,
c) S
|
for_each_busy_worker(a, c,
- b,
d) S
|
ax25_uid_for_each(a,
- b,
c) S
|
ax25_for_each(a,
- b,
c) S
|
inet_bind_bucket_for_each(a,
- b,
c) S
|
sctp_for_each_hentry(a,
- b,
c) S
|
sk_for_each(a,
- b,
c) S
|
sk_for_each_rcu(a,
- b,
c) S
|
sk_for_each_from
-(a, b)
+(a)
S
+ sk_for_each_from(a) S
|
sk_for_each_safe(a,
- b,
c, d) S
|
sk_for_each_bound(a,
- b,
c) S
|
hlist_for_each_entry_safe(a,
- b,
c, d, e) S
|
hlist_for_each_entry_continue_rcu(a,
- b,
c) S
|
nr_neigh_for_each(a,
- b,
c) S
|
nr_neigh_for_each_safe(a,
- b,
c, d) S
|
nr_node_for_each(a,
- b,
c) S
|
nr_node_for_each_safe(a,
- b,
c, d) S
|
- for_each_gfn_sp(a, c, d, b) S
+ for_each_gfn_sp(a, c, d) S
|
- for_each_gfn_indirect_valid_sp(a, c, d, b) S
+ for_each_gfn_indirect_valid_sp(a, c, d) S
|
for_each_host(a,
- b,
c) S
|
for_each_host_safe(a,
- b,
c, d) S
|
for_each_mesh_entry(a,
- b,
c, d) S
)
    ...+>

[akpm@linux-foundation.org: drop bogus change from net/ipv4/raw.c]
[akpm@linux-foundation.org: drop bogus hunk from net/ipv6/raw.c]
[akpm@linux-foundation.org: checkpatch fixes]
[akpm@linux-foundation.org: fix warnings]
[akpm@linux-foudnation.org: redo intrusive kvm changes]
Tested-by: NPeter Senna Tschudin <peter.senna@gmail.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NSasha Levin <sasha.levin@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Gleb Natapov <gleb@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If gb_len is less than 3 it would cause an integer underflow and
possibly memory corruption in nfc_llcp_parse_gb_tlv().

I removed the old test for gb_len == 0.  I also removed the test for
->remote_gb == NULL.  It's not possible for ->remote_gb to be NULL and
we have already dereferenced ->remote_gb_len so it's too late to test.

The old test return -ENODEV but my test returns -EINVAL.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The reference count bump on the llcp Rx path is leading to a memory leak
whenever we're not receiving an I frame.
We fix that by removing the refcount bump (drivers must not free their
received skb) and using it only in the I frame path, when the frame is
actually queued. In that case, the skb will only be freed when someone
fetches it from userspace. in all other cases, LLCP received frames will
be freed when leaving the Rx work queue.
Reported-by: NEric Lapuyade <eric.lapuyade@linux.intel.com>
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>

nfc_llcp_ns(s) dereferences the s pointer which is freed a line
above. In a result, it can produce a crash or you will read
incorrect value.
Signed-off-by: NWaldemar Rymarkiewicz <waldemar.rymarkiewicz@tieto.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

list_add was called with swapped parameters
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Drivers are allowed to modify the sent skb and thus we need to make a copy
of it before passing it to the driver. Without this fix, LLCP Tx skbs were
not queued properly as the ptype check was failing due to e.g. the pn533
driver skb_pushing the Tx skb.
Reported-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

NFC_CMD_LLC_GET_PARAMS: request LTO, RW, and MIUX parameters for a device

NFC_CMD_LLC_SET_PARAMS: set one or more of LTO, RW, and MIUX parameters for
a device. LTO must be set before the link is up otherwise -EINPROGRESS is
returned. RW and MIUX can be set at anytime and will be passed in subsequent
CONNECT and CC messages. If one of the passed parameters is wrong none is
set and -EINVAL is returned.
Signed-off-by: NThierry Escande <thierry.escande@linux.intel.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The Tx queues are no longer valid when we receive a disconnection or when
the LLCP link goes down. In the later case we also purge the entire local
Tx queue.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Signed-off-by: NSzymon Janc <szymon.janc@tieto.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The previous code was always returning the last socket from the
LLCP socket list.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

UI (Unnumbered Information) frames are used for sending data over
connection less links.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

When DEP goes down, bound cl sockets can be kept alive as there is no
reason to kill a connection less server socket because the LLCP link
went down.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Connection less server sockets will be in BOUND state, not LISTEN.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

Replying to an SNL (Service Name Lookup) means that the other end of
the link can now rely on our answer (Which is an ssap) and thus we have
to reserve it.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

There is no need for return statement at the end of function returning
void.
Signed-off-by: NSzymon Janc <szymon.janc@tieto.com>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

SNL (Service Name Lookup) allows for LLCP peers to map service names with
SAPs. This is mandatory for connection less support as peers need to get
the right SAPs without sending the CONNECT frame.
Here we only support the Rx part of SNL. The Tx one will be implemented
when supporting connection less LLCP sockets.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

In some cases (SNL, DISC, DM) we need to send an LLCP skbs without
having a sock owning it. I frames are an exception here since
they may be requeued to the llcp_sock queue.
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

The network merge brought in a few users of functions that got
deprecated by the workqueue cleanups: the 'system_nrt_wq' is now the
same as the regular system_wq, since all workqueues are now non-
reentrant.

Similarly, remove one use of flush_work_sync() - the regular
flush_work() has become synchronous, and the "_sync()" version is thus
deprecated as being superfluous.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>