uapi: wireless: Replace zero-length array with flexible-array member

Zero-length and one-element arrays are deprecated, and we are moving
towards adopting C99 flexible-array members, instead.

Address the following warnings seen under GCC-13 and
-fstrict-flex-arrays=3 enabled:
drivers/staging/ks7010/ks_wlan_net.c:1597:50: warning: array subscript 0 is outside array bounds of ‘__u8[0]’ {aka ‘unsigned char[]’} [-Warray-bounds=]
drivers/staging/ks7010/ks_wlan_net.c:1603:61: warning: array subscript 16 is outside array bounds of ‘__u8[0]’ {aka ‘unsigned char[]’} [-Warray-bounds=]
drivers/staging/ks7010/ks_wlan_net.c:1604:61: warning: array subscript 24 is outside array bounds of ‘__u8[0]’ {aka ‘unsigned char[]’} [-Warray-bounds=]
drivers/staging/ks7010/ks_wlan_net.c:1600:61: warning: array subscript 16 is outside array bounds of ‘__u8[0]’ {aka ‘unsigned char[]’} [-Warray-bounds=]
drivers/staging/ks7010/ks_wlan_net.c:1586:50: warning: array subscript 0 is outside array bounds of ‘__u8[0]’ {aka ‘unsigned char[]’} [-Warray-bounds=]

This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
routines on memcpy() and help us make progress towards globally
enabling -fstrict-flex-arrays=3 [1].

This results in no differences in binary output.

Link: https://github.com/KSPP/linux/issues/21
Link: https://github.com/KSPP/linux/issues/261
Link: https://gcc.gnu.org/pipermail/gcc-patches/2022-October/602902.html [1]
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

net/wireless: wireless.h: drop duplicate word in comments

Drop doubled word "threshold" in a comment.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: netdev@vger.kernel.org
Cc: Kalle Valo <kvalo@codeaurora.org>
Cc: linux-wireless@vger.kernel.org
Cc: Johannes Berg <johannes@sipsolutions.net>
Link: https://lore.kernel.org/r/20200715164325.9109-2-rdunlap@infradead.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wireless: Use linux/stddef.h instead of stddef.h

When compiling inside the kernel include linux/stddef.h instead of
stddef.h. When I compile this header file in backports for power PC I
run into a conflict with ptrdiff_t. I was unable to reproduce this in
mainline kernel. I still would like to fix this problem in the kernel.

Fixes: 6989310f5d43 ("wireless: Use offsetof instead of custom macro.")
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Link: https://lore.kernel.org/r/20200521201422.16493-1-hauke@hauke-m.de
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wireless: Use offsetof instead of custom macro.

Use offsetof to calculate offset of a field to take advantage of
compiler built-in version when possible, and avoid UBSAN warning when
compiling with Clang:

==================================================================
UBSAN: Undefined behaviour in net/wireless/wext-core.c:525:14
member access within null pointer of type 'struct iw_point'
CPU: 3 PID: 165 Comm: kworker/u16:3 Tainted: G S W 4.19.23 #43
Workqueue: cfg80211 __cfg80211_scan_done [cfg80211]
Call trace:
dump_backtrace+0x0/0x194
show_stack+0x20/0x2c
__dump_stack+0x20/0x28
dump_stack+0x70/0x94
ubsan_epilogue+0x14/0x44
ubsan_type_mismatch_common+0xf4/0xfc
__ubsan_handle_type_mismatch_v1+0x34/0x54
wireless_send_event+0x3cc/0x470
___cfg80211_scan_done+0x13c/0x220 [cfg80211]
__cfg80211_scan_done+0x28/0x34 [cfg80211]
process_one_work+0x170/0x35c
worker_thread+0x254/0x380
kthread+0x13c/0x158
ret_from_fork+0x10/0x18
===================================================================

Signed-off-by: Pi-Hsun Shih <pihsun@chromium.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20191204081307.138765-1-pihsun@chromium.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

License cleanup: add SPDX license identifier to uapi header files with no license

Many user space API headers are missing licensing information, which
makes it hard for compliance tools to determine the correct license.

By default are files without license information under the default
license of the kernel, which is GPLV2. Marking them GPLV2 would exclude
them from being included in non GPLV2 code, which is obviously not
intended. The user space API headers fall under the syscall exception
which is in the kernels COPYING file:

NOTE! This copyright does *not* cover user programs that use kernel
services by normal system calls - this is merely considered normal use
of the kernel, and does *not* fall under the heading of "derived work".

otherwise syscall usage would not be possible.

Update the files which contain no license information with an SPDX
license identifier. The chosen identifier is 'GPL-2.0 WITH
Linux-syscall-note' which is the officially assigned identifier for the
Linux syscall exception. SPDX license identifiers are a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne. See the previous patch in this series for the
methodology of how this patch was researched.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

wext: reformat struct/union declarations

Everytime I need to look for these, my usual strategy fails
because it assumes the right formatting. Fix the formatting
here to make it consistent with the rest of the kernel.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

UAPI: (Scripted) Disintegrate include/linux

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>