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>

uapi: fix linux/packet_diag.h userspace compilation error

Replace MAX_ADDR_LEN with its numeric value to fix the following
linux/packet_diag.h userspace compilation error:

/usr/include/linux/packet_diag.h:67:17: error: 'MAX_ADDR_LEN' undeclared here (not in a function)
__u8 pdmc_addr[MAX_ADDR_LEN];

This is not the first case in the UAPI where the numeric value
of MAX_ADDR_LEN is used instead of symbolic one, uapi/linux/if_link.h
already does the same:

$ grep MAX_ADDR_LEN include/uapi/linux/if_link.h
__u8 mac[32]; /* MAX_ADDR_LEN */

There are no UAPI headers besides these two that use MAX_ADDR_LEN.

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Acked-by: Pavel Emelyanov <xemul@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diag: warn about missing first netlink attribute

The first netlink attribute (value 0) must always be defined as none/unspec.
This is correctly done in inet_diag.h, but other diag interfaces are wrong.

Because we cannot change an existing API, I add a comment to point the mistake
and avoid to propagate it in a new diag API in the future.

CC: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

sock_diag: allow to dump bpf filters

This patch allows to dump BPF filters attached to a socket with
SO_ATTACH_FILTER.
Note that we check CAP_SYS_ADMIN before allowing to dump this info.

For now, only AF_PACKET sockets use this feature.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

packet_diag: disclose meminfo values

sk_rmem_alloc is disclosed via /proc/net/packet but not via netlink messages.
The goal is to have the same level of information.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

packet_diag: disclose uid value

This value is disclosed via /proc/net/packet but not via netlink messages.
The goal is to have the same level of information.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: fix *_DIAG_MAX constants

Follow the common pattern and define *_DIAG_MAX like:

[...]
__XXX_DIAG_MAX,
};

Because everyone is used to do:

struct nlattr *attrs[XXX_DIAG_MAX+1];

nla_parse([...], XXX_DIAG_MAX, [...]

Reported-by: Thomas Graf <tgraf@suug.ch>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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>