netfilter: gre: Remove unused function declaration nf_ct_gre_keymap_flush()

Commit a23f89a99906 ("netfilter: conntrack: nf_ct_gre_keymap_flush() removal")
leave this unused, remove it.

Signed-off-by: Yue Haibing <yuehaibing@huawei.com>
Signed-off-by: Florian Westphal <fw@strlen.de>

netfilter: remove "#ifdef __KERNEL__" guards from some headers.

A number of non-UAPI Netfilter header-files contained superfluous
"#ifdef __KERNEL__" guards. Removed them.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: conntrack: remove pkt_to_tuple callback

GRE is now builtin, so we can handle it via direct call and
remove the callback.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: conntrack: gre: switch module to be built-in

This makes the last of the modular l4 trackers 'bool'.

After this, all infrastructure to handle dynamic l4 protocol registration
becomes obsolete and can be removed in followup patches.

Old:
302824 net/netfilter/nf_conntrack.ko
21504 net/netfilter/nf_conntrack_proto_gre.ko

New:
313728 net/netfilter/nf_conntrack.ko

Old:
text data bss dec hex filename
6281 1732 4 8017 1f51 nf_conntrack_proto_gre.ko
108356 20613 236 129205 1f8b5 nf_conntrack.ko
New:
112095 21381 240 133716 20a54 nf_conntrack.ko

The size increase is only temporary.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: conntrack: gre: convert rwlock to rcu

We can use gre. Lock is only needed when a new expectation is added.

In case a single spinlock proves to be problematic we can either add one
per netns or use an array of locks combined with net_hash_mix() or similar
to pick the 'correct' one.

But given this is only needed for an expectation rather than per packet
a single one should be ok.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nat: remove nf_nat_l4proto struct

This removes the (now empty) nf_nat_l4proto struct, all its instances
and all the no longer needed runtime (un)register functionality.

nf_nat_need_gre() can be axed as well: the module that calls it (to
load the no-longer-existing nat_gre module) also calls other nat core
functions. GRE nat is now always available if kernel is built with it.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nfnetlink_cttimeout: fetch timeouts for udplite and gre, too

syzbot was able to trigger the WARN in cttimeout_default_get() by
passing UDPLITE as l4protocol. Alias UDPLITE to UDP, both use
same timeout values.

Furthermore, also fetch GRE timeouts. GRE is a bit more complicated,
as it still can be a module and its netns_proto_gre struct layout isn't
visible outside of the gre module. Can't move timeouts around, it
appears conntrack sysctl unregister assumes net_generic() returns
nf_proto_net, so we get crash. Expose layout of netns_proto_gre instead.

A followup nf-next patch could make gre tracker be built-in as well
if needed, its not that large.

Last, make the WARN() mention the missing protocol value in case
anything else is missing.

Reported-by: syzbot+2fae8fa157dd92618cae@syzkaller.appspotmail.com
Fixes: 8866df9264a3 ("netfilter: nfnetlink_cttimeout: pass default timeout policy to obj_to_nlattr")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is 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.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

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>

netfilter: gre: Use consistent GRE and PTTP header structure instead of the ones defined by netfilter

There are two existing strutures which defines the GRE and PPTP header.
So use these two structures instead of the ones defined by netfilter to
keep consitent with other codes.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: gre: Use consistent GRE_* macros instead of ones defined by netfilter.

There are already some GRE_* macros in kernel, so it is unnecessary
to define these macros. And remove some useless macros

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack: flush net_gre->keymap_list only from gre helper

nf_ct_gre_keymap_flush() removes a nf_ct_gre_keymap object from
net_gre->keymap_list and frees the object. But it doesn't clean
a reference on this object from ct_pptp_info->keymap[dir].
Then nf_ct_gre_keymap_destroy() may release the same object again.

So nf_ct_gre_keymap_flush() can be called only when we are sure that
when nf_ct_gre_keymap_destroy will not be called.

nf_ct_gre_keymap is created by nf_ct_gre_keymap_add() and the right way
to destroy it is to call nf_ct_gre_keymap_destroy().

This patch marks nf_ct_gre_keymap_flush() as static, so this patch can
break compilation of third party modules, which use
nf_ct_gre_keymap_flush. I'm not sure this is the right way to deprecate
this function.

[ 226.540793] general protection fault: 0000 [#1] SMP
[ 226.541750] Modules linked in: nf_nat_pptp nf_nat_proto_gre
nf_conntrack_pptp nf_conntrack_proto_gre ip_gre ip_tunnel gre
ppp_deflate bsd_comp ppp_async crc_ccitt ppp_generic slhc xt_nat
iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat
nf_conntrack veth tun bridge stp llc ppdev microcode joydev pcspkr
serio_raw virtio_console virtio_balloon floppy parport_pc parport
pvpanic i2c_piix4 virtio_net drm_kms_helper ttm ata_generic virtio_pci
virtio_ring virtio drm i2c_core pata_acpi [last unloaded: ip_tunnel]
[ 226.541776] CPU: 0 PID: 49 Comm: kworker/u4:2 Not tainted 3.14.0-rc8+ #101
[ 226.541776] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[ 226.541776] Workqueue: netns cleanup_net
[ 226.541776] task: ffff8800371e0000 ti: ffff88003730c000 task.ti: ffff88003730c000
[ 226.541776] RIP: 0010:[<ffffffff81389ba9>] [<ffffffff81389ba9>] __list_del_entry+0x29/0xd0
[ 226.541776] RSP: 0018:ffff88003730dbd0 EFLAGS: 00010a83
[ 226.541776] RAX: 6b6b6b6b6b6b6b6b RBX: ffff8800374e6c40 RCX: dead000000200200
[ 226.541776] RDX: 6b6b6b6b6b6b6b6b RSI: ffff8800371e07d0 RDI: ffff8800374e6c40
[ 226.541776] RBP: ffff88003730dbd0 R08: 0000000000000000 R09: 0000000000000000
[ 226.541776] R10: 0000000000000001 R11: ffff88003730d92e R12: 0000000000000002
[ 226.541776] R13: ffff88007a4c42d0 R14: ffff88007aef0000 R15: ffff880036cf0018
[ 226.541776] FS: 0000000000000000(0000) GS:ffff88007fc00000(0000) knlGS:0000000000000000
[ 226.541776] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 226.541776] CR2: 00007f07f643f7d0 CR3: 0000000036fd2000 CR4: 00000000000006f0
[ 226.541776] Stack:
[ 226.541776] ffff88003730dbe8 ffffffff81389c5d ffff8800374ffbe4 ffff88003730dc28
[ 226.541776] ffffffffa0162a43 ffffffffa01627c5 ffff88007a4c42d0 ffff88007aef0000
[ 226.541776] ffffffffa01651c0 ffff88007a4c45e0 ffff88007aef0000 ffff88003730dc40
[ 226.541776] Call Trace:
[ 226.541776] [<ffffffff81389c5d>] list_del+0xd/0x30
[ 226.541776] [<ffffffffa0162a43>] nf_ct_gre_keymap_destroy+0x283/0x2d0 [nf_conntrack_proto_gre]
[ 226.541776] [<ffffffffa01627c5>] ? nf_ct_gre_keymap_destroy+0x5/0x2d0 [nf_conntrack_proto_gre]
[ 226.541776] [<ffffffffa0162ab7>] gre_destroy+0x27/0x70 [nf_conntrack_proto_gre]
[ 226.541776] [<ffffffffa0117de3>] destroy_conntrack+0x83/0x200 [nf_conntrack]
[ 226.541776] [<ffffffffa0117d87>] ? destroy_conntrack+0x27/0x200 [nf_conntrack]
[ 226.541776] [<ffffffffa0117d60>] ? nf_conntrack_hash_check_insert+0x2e0/0x2e0 [nf_conntrack]
[ 226.541776] [<ffffffff81630142>] nf_conntrack_destroy+0x72/0x180
[ 226.541776] [<ffffffff816300d5>] ? nf_conntrack_destroy+0x5/0x180
[ 226.541776] [<ffffffffa011ef80>] ? kill_l3proto+0x20/0x20 [nf_conntrack]
[ 226.541776] [<ffffffffa011847e>] nf_ct_iterate_cleanup+0x14e/0x170 [nf_conntrack]
[ 226.541776] [<ffffffffa011f74b>] nf_ct_l4proto_pernet_unregister+0x5b/0x90 [nf_conntrack]
[ 226.541776] [<ffffffffa0162409>] proto_gre_net_exit+0x19/0x30 [nf_conntrack_proto_gre]
[ 226.541776] [<ffffffff815edf89>] ops_exit_list.isra.1+0x39/0x60
[ 226.541776] [<ffffffff815eecc0>] cleanup_net+0x100/0x1d0
[ 226.541776] [<ffffffff810a608a>] process_one_work+0x1ea/0x4f0
[ 226.541776] [<ffffffff810a6028>] ? process_one_work+0x188/0x4f0
[ 226.541776] [<ffffffff810a64ab>] worker_thread+0x11b/0x3a0
[ 226.541776] [<ffffffff810a6390>] ? process_one_work+0x4f0/0x4f0
[ 226.541776] [<ffffffff810af42d>] kthread+0xed/0x110
[ 226.541776] [<ffffffff8173d4dc>] ? _raw_spin_unlock_irq+0x2c/0x40
[ 226.541776] [<ffffffff810af340>] ? kthread_create_on_node+0x200/0x200
[ 226.541776] [<ffffffff8174747c>] ret_from_fork+0x7c/0xb0
[ 226.541776] [<ffffffff810af340>] ? kthread_create_on_node+0x200/0x200
[ 226.541776] Code: 00 00 55 48 8b 17 48 b9 00 01 10 00 00 00 ad de
48 8b 47 08 48 89 e5 48 39 ca 74 29 48 b9 00 02 20 00 00 00 ad de 48
39 c8 74 7a <4c> 8b 00 4c 39 c7 75 53 4c 8b 42 08 4c 39 c7 75 2b 48 89
42 08
[ 226.541776] RIP [<ffffffff81389ba9>] __list_del_entry+0x29/0xd0
[ 226.541776] RSP <ffff88003730dbd0>
[ 226.612193] ---[ end trace 985ae23ddfcc357c ]---

Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Andrey Vagin <avagin@openvz.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: Remove extern from function prototypes

There are a mix of function prototypes with and without extern
in the kernel sources. Standardize on not using extern for
function prototypes.

Function prototypes don't need to be written with extern.
extern is assumed by the compiler. Its use is as unnecessary as
using auto to declare automatic/local variables in a block.

Signed-off-by: Joe Perches <joe@perches.com>

Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

netfilter: netns nf_conntrack: GRE conntracking in netns

* make keymap list per-netns
* per-netns keymal lock (not strictly necessary)
* flush keymap at netns stop and module unload.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

[NETFILTER]: nf_nat_proto_gre: do not modify/corrupt GREv0 packets through NAT

While porting some changes of the 2.6.21-rc7 pptp/proto_gre conntrack
and nat modules to a 2.4.32 kernel I noticed that the gre_key function
returns a wrong pointer to the GRE key of a version 0 packet thus
corrupting the packet payload.

The intended behaviour for GREv0 packets is to act like
nf_conntrack_proto_generic/nf_nat_proto_unknown so I have ripped the
offending functions (not used anymore) and modified the
nf_nat_proto_gre modules to not touch version 0 (non PPTP) packets.

Signed-off-by: Jorge Boncompte <jorge@dti2.net>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack/nf_nat: add PPTP helper port

Add nf_conntrack port of the PPtP conntrack/NAT helper. Since there seems
to be no IPv6-capable PPtP implementation the helper only support IPv4.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>