netfilter: conntrack: gre: don't set assured flag for clash entries

Now that conntrack core is allowd to insert clashing entries, make sure
GRE won't set assured flag on NAT_CLASH entries, just like UDP.

Doing so prevents early_drop logic for these entries.

Fixes: d671fd82eaa9 ("netfilter: conntrack: allow insertion clash of gre protocol")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: conntrack: allow insertion clash of gre protocol

NVGRE tunnel is used in the VM-to-VM communications. The VM packets
are encapsulated in NVGRE and sent from the host. For NVGRE
there are two tuples(outer sip and outer dip) in the host conntrack item.
Insertion clashes are more likely to happen if the concurrent connections
are sent from the VM.

Signed-off-by: Faicker Mo <faicker.mo@ucloud.cn>
Signed-off-by: Florian Westphal <fw@strlen.de>

netfilter: conntrack: nf_ct_gre_keymap_flush() removal

nf_ct_gre_keymap_flush() is useless.
It is called from nf_conntrack_cleanup_net_list() only and tries to remove
nf_ct_gre_keymap entries from pernet gre keymap list. Though:
a) at this point the list should already be empty, all its entries were
deleted during the conntracks cleanup, because
nf_conntrack_cleanup_net_list() executes nf_ct_iterate_cleanup(kill_all)
before nf_conntrack_proto_pernet_fini():
nf_conntrack_cleanup_net_list
+- nf_ct_iterate_cleanup
| nf_ct_put
| nf_conntrack_put
| nf_conntrack_destroy
| destroy_conntrack
| destroy_gre_conntrack
| nf_ct_gre_keymap_destroy
`- nf_conntrack_proto_pernet_fini
nf_ct_gre_keymap_flush

b) Let's say we find that the keymap list is not empty. This means netns
still has a conntrack associated with gre, in which case we should not free
its memory, because this will lead to a double free and related crashes.
However I doubt it could have gone unnoticed for years, obviously
this does not happen in real life. So I think we can remove
both nf_ct_gre_keymap_flush() and nf_conntrack_proto_pernet_fini().

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: conntrack: Fix gre tunneling over ipv6

This fix permits gre connections to be tracked within ip6tables rules

Signed-off-by: Ludovic Senecaux <linuxludo@free.fr>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: Update obsolete comments referring to ip_conntrack

In 9fb9cbb1082d ("[NETFILTER]: Add nf_conntrack subsystem.") the new
generic nf_conntrack was introduced, and it came to supersede the old
ip_conntrack.

This change updates (some) of the obsolete comments referring to old
file/function names of the ip_conntrack mechanism, as well as removes a
few self-referencing comments that we shouldn't maintain anymore.

I did not update any comments referring to historical actions (e.g,
comments like "this file was derived from ..." were left untouched, even
if the referenced file is no longer here).

Signed-off-by: Yonatan Goldschmidt <yon.goldschmidt@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

treewide: Add SPDX license identifier for missed files

Add SPDX license identifiers to all files which:

- Have no license information of any form

- Have EXPORT_.*_SYMBOL_GPL inside which was used in the
initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

GPL-2.0-only

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

netfilter: conntrack: remove l4proto destroy hook

Only one user (gre), add a direct call and remove this facility.

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

netfilter: conntrack: remove l4proto init and get_net callbacks

Those were needed we still had modular trackers.
As we don't have those anymore, prefer direct calls and remove all
the (un)register infrastructure associated with this.

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

netfilter: conntrack: unify sysctl handling

Due to historical reasons, all l4 trackers register their own
sysctls.

This leads to copy&pasted boilerplate code, that does exactly same
thing, just with different data structure.

Place all of this in a single file.

This allows to remove the various ctl_table pointers from the ct_netns
structure and reduces overall code size.

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

netfilter: conntrack: remove remaining l4proto indirect packet calls

Now that all l4trackers are builtin, no need to use a mix of direct and
indirect calls.
This removes the last two users: gre and the generic l4 protocol
tracker.

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

netfilter: conntrack: remove module owner field

No need to get/put module owner reference, none of these can be removed
anymore.

Signed-off-by: Florian Westphal <fw@strlen.de>
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: conntrack: register sysctl table for gre

This patch adds two sysctl knobs for GRE:

net.netfilter.nf_conntrack_gre_timeout = 30
net.netfilter.nf_conntrack_gre_timeout_stream = 180

Update the Documentation as well.

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
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>

netfilter: conntrack: remove l3->l4 mapping information

l4 protocols are demuxed by l3num, l4num pair.

However, almost all l4 trackers are l3 agnostic.

Only exceptions are:
- gre, icmp (ipv4 only)
- icmpv6 (ipv6 only)

This commit gets rid of the l3 mapping, l4 trackers can now be looked up
by their IPPROTO_XXX value alone, which gets rid of the additional l3
indirection.

For icmp, ipcmp6 and gre, add a check on state->pf and
return -NF_ACCEPT in case we're asked to track e.g. icmpv6-in-ipv4,
this seems more fitting than using the generic tracker.

Additionally we can kill the 2nd l4proto definitions that were needed
for v4/v6 split -- they are now the same so we can use single l4proto
struct for each protocol, rather than two.

The EXPORT_SYMBOLs can be removed as all these object files are
part of nf_conntrack with no external references.

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

netfilter: conntrack: remove unused proto arg from netns init functions

Its unused, next patch will remove l4proto->l3proto number to simplify
l4 protocol demuxer lookup.

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

netfilter: conntrack: deconstify packet callback skb pointer

Only two protocols need the ->error() function: icmp and icmpv6.
This is because icmp error mssages might be RELATED to an existing
connection (e.g. PMTUD, port unreachable and the like), and their
->error() handlers do this.

The error callback is already optional, so remove it for
udp and call them from ->packet() instead.

As the error() callback can call checksum functions that write to
skb->csum*, the const qualifier has to be removed as well.

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

netfilter: conntrack: remove the l4proto->new() function

->new() gets invoked after ->error() and before ->packet() if
a conntrack lookup has found no result for the tuple.

We can fold it into ->packet() -- the packet() implementations
can check if the conntrack is confirmed (new) or not
(already in hash).

If its unconfirmed, the conntrack isn't in the hash yet so current
skb created a new conntrack entry.

Only relevant side effect -- if packet() doesn't return NF_ACCEPT
but -NF_ACCEPT (or drop), while the conntrack was just created,
then the newly allocated conntrack is freed right away, rather than not
created in the first place.

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

netfilter: conntrack: pass nf_hook_state to packet and error handlers

nf_hook_state contains all the hook meta-information: netns, protocol family,
hook location, and so on.

Instead of only passing selected information, pass a pointer to entire
structure.

This will allow to merge the error and the packet handlers and remove
the ->new() function in followup patches.

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

netfilter: conntrack: timeout interface depend on CONFIG_NF_CONNTRACK_TIMEOUT

Now that cttimeout support for nft_ct is in place, these should depend
on CONFIG_NF_CONNTRACK_TIMEOUT otherwise we can crash when dumping the
policy if this option is not enabled.

[ 71.600121] BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
[...]
[ 71.600141] CPU: 3 PID: 7612 Comm: nft Not tainted 4.18.0+ #246
[...]
[ 71.600188] Call Trace:
[ 71.600201] ? nft_ct_timeout_obj_dump+0xc6/0xf0 [nft_ct]

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: conntrack: remove get_timeout() indirection

Not needed, we can have the l4trackers fetch it themselvs.

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

netfilter: conntrack: avoid calls to l4proto invert_tuple

Handle the common cases (tcp, udp, etc). in the core and only
do the indirect call for the protocols that need it (GRE for instance).

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

net: Drop pernet_operations::async

Synchronous pernet_operations are not allowed anymore.
All are asynchronous. So, drop the structure member.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Convert proto_gre_net_ops

These pernet_operations register and unregister sysctl.
nf_conntrack_l4proto_gre4->init_net is simple memory
initializer. Also, exit method removes gre keymap_list,
which is per-net. This looks safe to be executed
in parallel with other pernet_operations.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: conntrack: timeouts can be const

Nowadays this is just the default template that is used when setting up
the net namespace, so nothing writes to these locations.

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

netfilter: conntrack: l4 protocol trackers can be const

previous patches removed all writes to these structs so we can
now mark them as const.

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

netfilter: conntrack: remove pf argument from l4 packet functions

not needed/used anymore.

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

netfilter: remove unused hooknum arg from packet functions

tested with allmodconfig build.

Signed-off-by: Florian Westphal <fw@strlen.de>

netfilter: conntrack: print_conntrack only needed if CONFIG_NF_CONNTRACK_PROCFS

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

netfilter: conntrack: place print_tuple in procfs part

CONFIG_NF_CONNTRACK_PROCFS is deprecated, no need to use a function
pointer in the trackers for this. Place the printf formatting in
the one place that uses it.

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

netfilter: conntrack: remove protocol name from l4proto struct

no need to waste storage for something that is only needed
in one place and can be deduced from protocol number.

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

netns: make struct pernet_operations::id unsigned int

Make struct pernet_operations::id unsigned.

There are 2 reasons to do so:

1)
This field is really an index into an zero based array and
thus is unsigned entity. Using negative value is out-of-bound
access by definition.

2)
On x86_64 unsigned 32-bit data which are mixed with pointers
via array indexing or offsets added or subtracted to pointers
are preffered to signed 32-bit data.

"int" being used as an array index needs to be sign-extended
to 64-bit before being used.

void f(long *p, int i)
{
g(p[i]);
}

roughly translates to

movsx rsi, esi
mov rdi, [rsi+...]
call g

MOVSX is 3 byte instruction which isn't necessary if the variable is
unsigned because x86_64 is zero extending by default.

Now, there is net_generic() function which, you guessed it right, uses
"int" as an array index:

static inline void *net_generic(const struct net *net, int id)
{
...
ptr = ng->ptr[id - 1];
...
}

And this function is used a lot, so those sign extensions add up.

Patch snipes ~1730 bytes on allyesconfig kernel (without all junk
messing with code generation):

add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)

Unfortunately some functions actually grow bigger.
This is a semmingly random artefact of code generation with register
allocator being used differently. gcc decides that some variable
needs to live in new r8+ registers and every access now requires REX
prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be
used which is longer than [r8]

However, overall balance is in negative direction:

add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730)
function old new delta
nfsd4_lock 3886 3959 +73
tipc_link_build_proto_msg 1096 1140 +44
mac80211_hwsim_new_radio 2776 2808 +32
tipc_mon_rcv 1032 1058 +26
svcauth_gss_legacy_init 1413 1429 +16
tipc_bcbase_select_primary 379 392 +13
nfsd4_exchange_id 1247 1260 +13
nfsd4_setclientid_confirm 782 793 +11
...
put_client_renew_locked 494 480 -14
ip_set_sockfn_get 730 716 -14
geneve_sock_add 829 813 -16
nfsd4_sequence_done 721 703 -18
nlmclnt_lookup_host 708 686 -22
nfsd4_lockt 1085 1063 -22
nfs_get_client 1077 1050 -27
tcf_bpf_init 1106 1076 -30
nfsd4_encode_fattr 5997 5930 -67
Total: Before=154856051, After=154854321, chg -0.00%

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: conntrack: simplify init/uninit of L4 protocol trackers

modify registration and deregistration of layer-4 protocol trackers to
facilitate inclusion of new elements into the current list of builtin
protocols. Both builtin (TCP, UDP, ICMP) and non-builtin (DCCP, GRE, SCTP,
UDPlite) layer-4 protocol trackers usually register/deregister themselves
using consecutive calls to nf_ct_l4proto_{,pernet}_{,un}register(...).
This sequence is interrupted and rolled back in case of error; in order to
simplify addition of builtin protocols, the input of the above functions
has been modified to allow registering/unregistering multiple protocols.

Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.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: Add a struct net parameter to l4_pkt_to_tuple

As gre does not have the srckey in the packet gre_pkt_to_tuple
needs to perform a lookup in it's per network namespace tables.

Pass in the proper network namespace to all pkt_to_tuple
implementations to ensure gre (and any similar protocols) can get this
right.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: Convert print_tuple functions to return void

Since adding a new function to seq_file (seq_has_overflowed())
there isn't any value for functions called from seq_show to
return anything. Remove the int returns of the various
print_tuple/<foo>_print_tuple functions.

Link: http://lkml.kernel.org/p/f2e8cf8df433a197daa62cbaf124c900c708edc7.1412031505.git.joe@perches.com

Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: netfilter-devel@vger.kernel.org
Cc: coreteam@netfilter.org
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

netfilter: Remove return values for print_conntrack callbacks

The seq_printf() and friends are having their return values removed.
The print_conntrack() returns the result of seq_printf(), which is
meaningless when seq_printf() returns void. Might as well remove the
return values of print_conntrack() as well.

Link: http://lkml.kernel.org/r/20141029220107.465008329@goodmis.org
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: netfilter-devel@vger.kernel.org
Cc: coreteam@netfilter.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.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: add my copyright statements

Add copyright statements to all netfilter files which have had significant
changes done by myself in the past.

Some notes:

- nf_conntrack_ecache.c was incorrectly attributed to Rusty and Netfilter
Core Team when it got split out of nf_conntrack_core.c. The copyrights
even state a date which lies six years before it was written. It was
written in 2005 by Harald and myself.

- net/ipv{4,6}/netfilter.c, net/netfitler/nf_queue.c were missing copyright
statements. I've added the copyright statement from net/netfilter/core.c,
where this code originated

- for nf_conntrack_proto_tcp.c I've also added Jozsef, since I didn't want
it to give the wrong impression

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack: register pernet subsystem before register L4 proto

In (c296bb4 netfilter: nf_conntrack: refactor l4proto support for netns)
the l4proto gre/dccp/udplite/sctp registration happened before the pernet
subsystem, which is wrong.

Register pernet subsystem before register L4proto since after register
L4proto, init_conntrack may try to access the resources which allocated
in register_pernet_subsys.

Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack: refactor l4proto support for netns

Move the code that register/unregister l4proto to the
module_init/exit context.

Given that we have to modify some interfaces to accomodate
these changes, it is a good time to use shorter function names
for this using the nf_ct_* prefix instead of nf_conntrack_*,
that is:

nf_ct_l4proto_register
nf_ct_l4proto_pernet_register
nf_ct_l4proto_unregister
nf_ct_l4proto_pernet_unregister

We same many line breaks with it.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack: prepare l4proto->init_net cleanup

l4proto->init contain quite redundant code. We can simplify this
by adding a new parameter l3proto.

This patch prepares that code simplification.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_helper: implement variable length helper private data

This patch uses the new variable length conntrack extensions.

Instead of using union nf_conntrack_help that contain all the
helper private data information, we allocate variable length
area to store the private helper data.

This patch includes the modification of all existing helpers.
It also includes a couple of include header to avoid compilation
warnings.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack: add namespace support for cttimeout

This patch adds namespace support for cttimeout.

Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_gre: use new namespace support

This patch modifies the GRE protocol tracker, which partially
supported namespace before this patch, to use the new namespace
infrastructure for nf_conntrack.

Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack: prepare namespace support for l4 protocol trackers

This patch prepares the namespace support for layer 4 protocol trackers.
Basically, this modifies the following interfaces:

* nf_ct_[un]register_sysctl
* nf_conntrack_l4proto_[un]register

to include the namespace parameter. We still use init_net in this patch
to prepare the ground for follow-up patches for each layer 4 protocol
tracker.

We add a new net_id field to struct nf_conntrack_l4proto that is used
to store the pernet_operations id for each layer 4 protocol tracker.

Note that AF_INET6's protocols do not need to do sysctl compat. Thus,
we only register compat sysctl when l4proto.l3proto != AF_INET6.

Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

nf_conntrack_proto_gre: Stop using NLA_PUT*().

These macros contain a hidden goto, and are thus extremely error
prone and make code hard to audit.

Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: add cttimeout infrastructure for fine timeout tuning

This patch adds the infrastructure to add fine timeout tuning
over nfnetlink. Now you can use the NFNL_SUBSYS_CTNETLINK_TIMEOUT
subsystem to create/delete/dump timeout objects that contain some
specific timeout policy for one flow.

The follow up patches will allow you attach timeout policy object
to conntrack via the CT target and the conntrack extension
infrastructure.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_conntrack: pass timeout array to l4->new and l4->packet

This patch defines a new interface for l4 protocol trackers:

unsigned int *(*get_timeouts)(struct net *net);

that is used to return the array of unsigned int that contains
the timeouts that will be applied for this flow. This is passed
to the l4proto->new(...) and l4proto->packet(...) functions to
specify the timeout policy.

This interface allows per-net global timeout configuration
(although only DCCP supports this by now) and it will allow
custom custom timeout configuration by means of follow-up
patches.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

netfilter: nf_ct_gre: add unsigned int array to define timeouts

This patch adds an array to define the default GRE timeouts.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net:netfilter: use IS_ENABLED

Use IS_ENABLED(CONFIG_FOO)
instead of defined(CONFIG_FOO) || defined (CONFIG_FOO_MODULE)

Signed-off-by: Igor Maravić <igorm@etf.rs>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: nf_conntrack: fix event flooding in GRE protocol tracker

GRE connections cause ctnetlink event flood because the ASSURED event
is set for every packet received.

Reported-by: Denys Fedoryshchenko <denys@visp.net.lb>
Tested-by: Denys Fedoryshchenko <denys@visp.net.lb>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

netfilter: nf_conntrack: split up IPCT_STATUS event

Split up the IPCT_STATUS event into an IPCT_REPLY event, which is generated
when the IPS_SEEN_REPLY bit is set, and an IPCT_ASSURED event, which is
generated when the IPS_ASSURED bit is set.

In combination with a following patch to support selective event delivery,
this can be used for "sparse" conntrack replication: start replicating the
conntrack entry after it reached the ASSURED state and that way it's SYN-flood
resistant.

Signed-off-by: Patrick McHardy <kaber@trash.net>

net: Simplify conntrack_proto_gre pernet operations.

Take advantage of the new pernet automatic storage management,
and stop using compatibility network namespace functions.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netns: net_identifiers should be read_mostly

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: nf_conntrack: use per-conntrack locks for protocol data

Introduce per-conntrack locks and use them instead of the global protocol
locks to avoid contention. Especially tcp_lock shows up very high in
profiles on larger machines.

This will also allow to simplify the upcoming reliable event delivery patches.

Signed-off-by: Patrick McHardy <kaber@trash.net>

net: skb->dst accessors

Define three accessors to get/set dst attached to a skb

struct dst_entry *skb_dst(const struct sk_buff *skb)

void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst)

void skb_dst_drop(struct sk_buff *skb)
This one should replace occurrences of :
dst_release(skb->dst)
skb->dst = NULL;

Delete skb->dst field

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: nf_conntrack: calculate per-protocol nlattr size

Signed-off-by: Holger Eitzenberger <holger@eitzenberger.org>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: nf_conntrack_proto_gre: spread __exit

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

netfilter: nf_conntrack_proto_gre: switch to register_pernet_gen_subsys()

register_pernet_gen_device() can't be used is nf_conntrack_pptp module is
also used (compiled in or loaded).

Right now, proto_gre_net_exit() is called before nf_conntrack_pptp_net_exit().
The former shutdowns and frees GRE piece of netns, however the latter
absolutely needs it to flush keymap. Oops is inevitable.

Switch to shiny new register_pernet_gen_subsys() to get correct ordering in
netns ops list.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

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: netns nf_conntrack: pass conntrack to nf_conntrack_event_cache() not skb

This is cleaner, we already know conntrack to which event is relevant.

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

netfilter: Use unsigned types for hooknum and pf vars

and (try to) consistently use u_int8_t for the L3 family.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>

netfilter: nf_conntrack_gre: nf_ct_gre_keymap_flush() fixlet

It does "kfree(list_head)" which looks wrong because entity that was
allocated is definitely not list_head.

However, this all works because list_head is first item in
struct nf_ct_gre_keymap.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

netfilter: nf_conntrack_gre: more locking around keymap list

gre_keymap_list should be protected in all places.
(unless I'm misreading something)

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: nf_conntrack: replace NF_CT_DUMP_TUPLE macro indrection by function call

Directly call IPv4 and IPv6 variants where the address family is
easily known.

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>

[NETFILTER]: nf_conntrack: use bool type in struct nf_conntrack_l4proto

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>

[NETFILTER]: nf_{conntrack,nat}_proto_gre: annotate with const

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NETFILTER]: ctnetlink: use netlink policy

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

[NETFILTER]: nfnetlink: rename functions containing 'nfattr'

There is no struct nfattr anymore, rename functions to 'nlattr'.

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

[NETFILTER]: nf_conntrack: mark protocols __read_mostly

Also remove two unnecessary EXPORT_SYMBOLs and move the
nf_conntrack_l3proto_ipv4 declaration to the correct file.

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

[NETFILTER]: Convert DEBUGP to pr_debug

Convert DEBUGP to pr_debug and fix lots of non-compiling debug statements.

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

[NETFILTER]: nf_conntrack: fix helper module unload races

When a helper module is unloaded all conntracks refering to it have their
helper pointer NULLed out, leading to lots of races. In most places this
can be fixed by proper use of RCU (they do already check for != NULL,
but in a racy way), additionally nf_conntrack_expect_related needs to
bail out when no helper is present.

Also remove two paranoid BUG_ONs in nf_conntrack_proto_gre that are racy
and not worth fixing.

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

[NETFILTER]: nf_conntrack/nf_nat: fix incorrect config ifdefs

The nf_conntrack_netlink config option is named CONFIG_NF_CT_NETLINK,
but multiple files use CONFIG_IP_NF_CONNTRACK_NETLINK or
CONFIG_NF_CONNTRACK_NETLINK for ifdefs.

Fix this and reformat all CONFIG_NF_CT_NETLINK ifdefs to only use a line.

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>