Revert "netfilter: xt_quota: fix the behavior of xt_quota module"

This reverts commit e9837e55b0200da544a095a1fca36efd7fd3ba30.

When talking to Maze and Chenbo, we agreed to keep this back by now
due to problems in the ruleset listing path with 32-bit arches.

Signed-off-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: xt_quota: fix the behavior of xt_quota module

A major flaw of the current xt_quota module is that quota in a specific
rule gets reset every time there is a rule change in the same table. It
makes the xt_quota module not very useful in a table in which iptables
rules are changed at run time. This fix introduces a new counter that is
visible to userspace as the remaining quota of the current rule. When
userspace restores the rules in a table, it can restore the counter to
the remaining quota instead of resetting it to the full quota.

Signed-off-by: Chenbo Feng <fengc@google.com>
Suggested-by: Maciej Żenczykowski <maze@google.com>
Reviewed-by: Maciej Żenczykowski <maze@google.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

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: (Scripted) Disintegrate include/linux/netfilter

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>