6lowpan: iphc: Fix an off-by-one check of array index

The bounds check of id is off-by-one and the comparison should
be >= rather >. Currently the WARN_ON_ONCE check does not stop
the out of range indexing of &ldev->ctx.table[id] so also add
a return path if the bounds are out of range.

Addresses-Coverity: ("Illegal address computation").
Fixes: 5609c185f24d ("6lowpan: iphc: add support for stateful compression")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

6lowpan: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.

Because we don't care if debugfs works or not, this trickles back a bit
so we can clean things up by making some functions return void instead
of an error value that is never going to fail.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

6lowpan: no need to check return value of debugfs_create functions

When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.

Because we don't care if debugfs works or not, this trickles back a bit
so we can clean things up by making some functions return void instead
of an error value that is never going to fail.

Cc: Alexander Aring <alex.aring@gmail.com>
Cc: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-bluetooth@vger.kernel.org
Cc: linux-wpan@vger.kernel.org
Cc: netdev@vger.kernel.org
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation this program is
distributed in the hope that it will be useful but without any
warranty without even the implied warranty of merchantability or
fitness for a particular purpose see the gnu general public license
for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 655 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

6lowpan: fix debugfs_simple_attr.cocci warnings

Use DEFINE_DEBUGFS_ATTRIBUTE rather than DEFINE_SIMPLE_ATTRIBUTE
for debugfs files.

Semantic patch information:
Rationale: DEFINE_SIMPLE_ATTRIBUTE + debugfs_create_file()
imposes some significant overhead as compared to
DEFINE_DEBUGFS_ATTRIBUTE + debugfs_create_file_unsafe().

Generated by: scripts/coccinelle/api/debugfs/debugfs_simple_attr.cocci

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

6lowpan: convert to DEFINE_SHOW_ATTRIBUTE

Use DEFINE_SHOW_ATTRIBUTE macro to simplify the code.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

6lowpan: add support for getting short address

In case of sending RA messages we need some way to get the short address
from an 802.15.4 6LoWPAN interface. This patch will add a temporary
debugfs entry for experimental userspace api.

Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

6lowpan: change naming for lowpan private data

This patch changes the naming for interface private data for lowpan
intefaces. The current private data scheme is:

-------------------------------------------------
| 6LoWPAN Generic | LinkLayer 6LoWPAN |
-------------------------------------------------

the current naming schemes are:

- 6LoWPAN Generic:
- lowpan_priv
- LinkLayer 6LoWPAN:
- BTLE
- lowpan_dev
- 802.15.4:
- lowpan_dev_info

the new naming scheme with this patch will be:

- 6LoWPAN Generic:
- lowpan_dev
- LinkLayer 6LoWPAN:
- BTLE
- lowpan_btle_dev
- 802.15.4:
- lowpan_802154_dev

Signed-off-by: Alexander Aring <aar@pengutronix.de>
Reviewed-by: Stefan Schmidt<stefan@osg.samsung.com>
Acked-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

6lowpan: debugfs: add missing static

This patch solves the sparse warning:

net/6lowpan/debugfs.c:164:30: warning: symbol 'lowpan_ctx_pfx_fops' was
not declared. Should it be static?
net/6lowpan/debugfs.c:241:30: warning: symbol 'lowpan_context_fops' was
not declared. Should it be static?

Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

6lowpan: iphc: add support for stateful compression

This patch introduce support for IPHC stateful address compression. It
will offer the context table via one debugfs entry.
This debugfs has and directory for each cid entry for the context table.
Inside each cid directory there exists the following files:

- "active": If the entry is added or deleted. The context table is
original a list implementation, this flag will indicate if the
context is part of list or not.
- "prefix": The ipv6 prefix.
- "prefix_length": The prefix length for the prefix.
- "compression": The compression flag according RFC6775.

This part should be moved into sysfs after some testing time.

Also the debugfs entry contains a "show" file which is a pretty-printout
for the current context table information.

Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <aar@pengutronix.de>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

6lowpan: add debugfs support

This patch will introduce a 6lowpan entry into the debugfs if enabled.
Inside this 6lowpan directory we create a subdirectories of all 6lowpan
interfaces to offer a per interface debugfs support.

Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>