Commit Graph

162 Commits

Author SHA1 Message Date
David S. Miller 2aa2f88c97 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) Incorrect output device in nf_egress hook, from Phill Sutter.

2) Preserve liberal flag in TCP conntrack state, reported by Sven Auhagen.

3) Use GFP_KERNEL_ACCOUNT flag for nf_tables objects, from Vasily Averin.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-28 08:57:10 -07:00
Vasily Averin 33758c8914 memcg: enable accounting for nft objects
nftables replaces iptables, but it lacks memcg accounting.

This patch account most of the memory allocation associated with nft
and should protect the host from misusing nft inside a memcg restricted
container.

Signed-off-by: Vasily Averin <vvs@openvz.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-03-28 10:11:23 +02:00
Jakub Kicinski 80901bff81 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
net/batman-adv/hard-interface.c
  commit 690bb6fb64 ("batman-adv: Request iflink once in batadv-on-batadv check")
  commit 6ee3c393ee ("batman-adv: Demote batadv-on-batadv skip error message")
https://lore.kernel.org/all/20220302163049.101957-1-sw@simonwunderlich.de/

net/smc/af_smc.c
  commit 4d08b7b57e ("net/smc: Fix cleanup when register ULP fails")
  commit 462791bbfa ("net/smc: add sysctl interface for SMC")
https://lore.kernel.org/all/20220302112209.355def40@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-03 11:55:12 -08:00
Eric Dumazet 56763f12b0 netfilter: fix use-after-free in __nf_register_net_hook()
We must not dereference @new_hooks after nf_hook_mutex has been released,
because other threads might have freed our allocated hooks already.

BUG: KASAN: use-after-free in nf_hook_entries_get_hook_ops include/linux/netfilter.h:130 [inline]
BUG: KASAN: use-after-free in hooks_validate net/netfilter/core.c:171 [inline]
BUG: KASAN: use-after-free in __nf_register_net_hook+0x77a/0x820 net/netfilter/core.c:438
Read of size 2 at addr ffff88801c1a8000 by task syz-executor237/4430

CPU: 1 PID: 4430 Comm: syz-executor237 Not tainted 5.17.0-rc5-syzkaller-00306-g2293be58d6a1 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255
 __kasan_report mm/kasan/report.c:442 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
 nf_hook_entries_get_hook_ops include/linux/netfilter.h:130 [inline]
 hooks_validate net/netfilter/core.c:171 [inline]
 __nf_register_net_hook+0x77a/0x820 net/netfilter/core.c:438
 nf_register_net_hook+0x114/0x170 net/netfilter/core.c:571
 nf_register_net_hooks+0x59/0xc0 net/netfilter/core.c:587
 nf_synproxy_ipv6_init+0x85/0xe0 net/netfilter/nf_synproxy_core.c:1218
 synproxy_tg6_check+0x30d/0x560 net/ipv6/netfilter/ip6t_SYNPROXY.c:81
 xt_check_target+0x26c/0x9e0 net/netfilter/x_tables.c:1038
 check_target net/ipv6/netfilter/ip6_tables.c:530 [inline]
 find_check_entry.constprop.0+0x7f1/0x9e0 net/ipv6/netfilter/ip6_tables.c:573
 translate_table+0xc8b/0x1750 net/ipv6/netfilter/ip6_tables.c:735
 do_replace net/ipv6/netfilter/ip6_tables.c:1153 [inline]
 do_ip6t_set_ctl+0x56e/0xb90 net/ipv6/netfilter/ip6_tables.c:1639
 nf_setsockopt+0x83/0xe0 net/netfilter/nf_sockopt.c:101
 ipv6_setsockopt+0x122/0x180 net/ipv6/ipv6_sockglue.c:1024
 rawv6_setsockopt+0xd3/0x6a0 net/ipv6/raw.c:1084
 __sys_setsockopt+0x2db/0x610 net/socket.c:2180
 __do_sys_setsockopt net/socket.c:2191 [inline]
 __se_sys_setsockopt net/socket.c:2188 [inline]
 __x64_sys_setsockopt+0xba/0x150 net/socket.c:2188
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f65a1ace7d9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 71 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f65a1a7f308 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000006 RCX: 00007f65a1ace7d9
RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 00007f65a1b574c8 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000020000000 R11: 0000000000000246 R12: 00007f65a1b55130
R13: 00007f65a1b574c0 R14: 00007f65a1b24090 R15: 0000000000022000
 </TASK>

The buggy address belongs to the page:
page:ffffea0000706a00 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1c1a8
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0001c1b108 ffffea000046dd08 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x52dc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_ZERO), pid 4430, ts 1061781545818, free_ts 1061791488993
 prep_new_page mm/page_alloc.c:2434 [inline]
 get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389
 __alloc_pages_node include/linux/gfp.h:572 [inline]
 alloc_pages_node include/linux/gfp.h:595 [inline]
 kmalloc_large_node+0x62/0x130 mm/slub.c:4438
 __kmalloc_node+0x35a/0x4a0 mm/slub.c:4454
 kmalloc_node include/linux/slab.h:604 [inline]
 kvmalloc_node+0x97/0x100 mm/util.c:580
 kvmalloc include/linux/slab.h:731 [inline]
 kvzalloc include/linux/slab.h:739 [inline]
 allocate_hook_entries_size net/netfilter/core.c:61 [inline]
 nf_hook_entries_grow+0x140/0x780 net/netfilter/core.c:128
 __nf_register_net_hook+0x144/0x820 net/netfilter/core.c:429
 nf_register_net_hook+0x114/0x170 net/netfilter/core.c:571
 nf_register_net_hooks+0x59/0xc0 net/netfilter/core.c:587
 nf_synproxy_ipv6_init+0x85/0xe0 net/netfilter/nf_synproxy_core.c:1218
 synproxy_tg6_check+0x30d/0x560 net/ipv6/netfilter/ip6t_SYNPROXY.c:81
 xt_check_target+0x26c/0x9e0 net/netfilter/x_tables.c:1038
 check_target net/ipv6/netfilter/ip6_tables.c:530 [inline]
 find_check_entry.constprop.0+0x7f1/0x9e0 net/ipv6/netfilter/ip6_tables.c:573
 translate_table+0xc8b/0x1750 net/ipv6/netfilter/ip6_tables.c:735
 do_replace net/ipv6/netfilter/ip6_tables.c:1153 [inline]
 do_ip6t_set_ctl+0x56e/0xb90 net/ipv6/netfilter/ip6_tables.c:1639
 nf_setsockopt+0x83/0xe0 net/netfilter/nf_sockopt.c:101
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1352 [inline]
 free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404
 free_unref_page_prepare mm/page_alloc.c:3325 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3404
 kvfree+0x42/0x50 mm/util.c:613
 rcu_do_batch kernel/rcu/tree.c:2527 [inline]
 rcu_core+0x7b1/0x1820 kernel/rcu/tree.c:2778
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558

Memory state around the buggy address:
 ffff88801c1a7f00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88801c1a7f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88801c1a8000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88801c1a8080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88801c1a8100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff

Fixes: 2420b79f8c ("netfilter: debug: check for sorted array")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-02-28 22:34:04 +01:00
Menglong Dong 2df3041ba3 net: netfilter: use kfree_drop_reason() for NF_DROP
Replace kfree_skb() with kfree_skb_reason() in nf_hook_slow() when
skb is dropped by reason of NF_DROP. Following new drop reasons
are introduced:

SKB_DROP_REASON_NETFILTER_DROP

Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-07 11:18:49 +00:00
Florian Westphal 285c8a7a58 netfilter: make function op structures const
No functional changes, these structures should be const.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-01-09 23:30:13 +01:00
Florian Westphal 3fce16493d netfilter: core: move ip_ct_attach indirection to struct nf_ct_hook
ip_ct_attach predates struct nf_ct_hook, we can place it there and
remove the exported symbol.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-01-09 23:30:13 +01:00
Lukas Wunner ffdd33dd9c netfilter: core: Fix clang warnings about unused static inlines
Unlike gcc, clang warns about unused static inlines that are not in an
include file:

  net/netfilter/core.c:344:20: error: unused function 'nf_ingress_hook' [-Werror,-Wunused-function]
  static inline bool nf_ingress_hook(const struct nf_hook_ops *reg, int pf)
                     ^
  net/netfilter/core.c:353:20: error: unused function 'nf_egress_hook' [-Werror,-Wunused-function]
  static inline bool nf_egress_hook(const struct nf_hook_ops *reg, int pf)
                     ^

According to commit 6863f5643d ("kbuild: allow Clang to find unused
static inline functions for W=1 build"), the proper resolution is to
mark the affected functions as __maybe_unused.  An alternative approach
would be to move them to include/linux/netfilter_netdev.h, but since
Pablo didn't do that in commit ddcfa710d4 ("netfilter: add
nf_ingress_hook() helper function"), I'm guessing __maybe_unused is
preferred.

This fixes both the warning introduced by Pablo in v5.10 as well as the
one recently introduced by myself with commit 42df6e1d22 ("netfilter:
Introduce egress hook").

Fixes: ddcfa710d4 ("netfilter: add nf_ingress_hook() helper function")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-10-17 15:49:08 +02:00
Lukas Wunner 42df6e1d22 netfilter: Introduce egress hook
Support classifying packets with netfilter on egress to satisfy user
requirements such as:
* outbound security policies for containers (Laura)
* filtering and mangling intra-node Direct Server Return (DSR) traffic
  on a load balancer (Laura)
* filtering locally generated traffic coming in through AF_PACKET,
  such as local ARP traffic generated for clustering purposes or DHCP
  (Laura; the AF_PACKET plumbing is contained in a follow-up commit)
* L2 filtering from ingress and egress for AVB (Audio Video Bridging)
  and gPTP with nftables (Pablo)
* in the future: in-kernel NAT64/NAT46 (Pablo)

The egress hook introduced herein complements the ingress hook added by
commit e687ad60af ("netfilter: add netfilter ingress hook after
handle_ing() under unique static key").  A patch for nftables to hook up
egress rules from user space has been submitted separately, so users may
immediately take advantage of the feature.

Alternatively or in addition to netfilter, packets can be classified
with traffic control (tc).  On ingress, packets are classified first by
tc, then by netfilter.  On egress, the order is reversed for symmetry.
Conceptually, tc and netfilter can be thought of as layers, with
netfilter layered above tc.

Traffic control is capable of redirecting packets to another interface
(man 8 tc-mirred).  E.g., an ingress packet may be redirected from the
host namespace to a container via a veth connection:
tc ingress (host) -> tc egress (veth host) -> tc ingress (veth container)

In this case, netfilter egress classifying is not performed when leaving
the host namespace!  That's because the packet is still on the tc layer.
If tc redirects the packet to a physical interface in the host namespace
such that it leaves the system, the packet is never subjected to
netfilter egress classifying.  That is only logical since it hasn't
passed through netfilter ingress classifying either.

Packets can alternatively be redirected at the netfilter layer using
nft fwd.  Such a packet *is* subjected to netfilter egress classifying
since it has reached the netfilter layer.

Internally, the skb->nf_skip_egress flag controls whether netfilter is
invoked on egress by __dev_queue_xmit().  Because __dev_queue_xmit() may
be called recursively by tunnel drivers such as vxlan, the flag is
reverted to false after sch_handle_egress().  This ensures that
netfilter is applied both on the overlay and underlying network.

Interaction between tc and netfilter is possible by setting and querying
skb->mark.

If netfilter egress classifying is not enabled on any interface, it is
patched out of the data path by way of a static_key and doesn't make a
performance difference that is discernible from noise:

Before:             1537 1538 1538 1537 1538 1537 Mb/sec
After:              1536 1534 1539 1539 1539 1540 Mb/sec
Before + tc accept: 1418 1418 1418 1419 1419 1418 Mb/sec
After  + tc accept: 1419 1424 1418 1419 1422 1420 Mb/sec
Before + tc drop:   1620 1619 1619 1619 1620 1620 Mb/sec
After  + tc drop:   1616 1624 1625 1624 1622 1619 Mb/sec

When netfilter egress classifying is enabled on at least one interface,
a minimal performance penalty is incurred for every egress packet, even
if the interface it's transmitted over doesn't have any netfilter egress
rules configured.  That is caused by checking dev->nf_hooks_egress
against NULL.

Measurements were performed on a Core i7-3615QM.  Commands to reproduce:
ip link add dev foo type dummy
ip link set dev foo up
modprobe pktgen
echo "add_device foo" > /proc/net/pktgen/kpktgend_3
samples/pktgen/pktgen_bench_xmit_mode_queue_xmit.sh -i foo -n 400000000 -m "11:11:11:11:11:11" -d 1.1.1.1

Accept all traffic with tc:
tc qdisc add dev foo clsact
tc filter add dev foo egress bpf da bytecode '1,6 0 0 0,'

Drop all traffic with tc:
tc qdisc add dev foo clsact
tc filter add dev foo egress bpf da bytecode '1,6 0 0 2,'

Apply this patch when measuring packet drops to avoid errors in dmesg:
https://lore.kernel.org/netdev/a73dda33-57f4-95d8-ea51-ed483abd6a7a@iogearbox.net/

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Laura García Liébana <nevola@gmail.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-10-14 23:06:28 +02:00
Pablo Neira Ayuso 60a3815da7 netfilter: add inet ingress support
This patch adds the NF_INET_INGRESS pseudohook for the NFPROTO_INET
family. This is a mapping this new hook to the existing NFPROTO_NETDEV
and NF_NETDEV_INGRESS hook. The hook does not guarantee that packets are
inet only, users must filter out non-ip traffic explicitly.

This infrastructure makes it easier to support this new hook in nf_tables.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-10-12 01:57:34 +02:00
Pablo Neira Ayuso ddcfa710d4 netfilter: add nf_ingress_hook() helper function
Add helper function to check if this is an ingress hook.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-10-12 01:57:34 +02:00
Pablo Neira Ayuso afd9024cd1 netfilter: add nf_static_key_{inc,dec}
Add helper functions increment and decrement the hook static keys.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2020-10-12 01:57:34 +02:00
Will Deacon 514cc55b01 netfilter: Avoid assigning 'const' pointer to non-const pointer
nf_remove_net_hook() uses WRITE_ONCE() to assign a 'const' pointer to a
'non-const' pointer. Cleanups to the implementation of WRITE_ONCE() mean
that this will give rise to a compiler warning, just like a plain old
assignment would do:

  | In file included from ./include/linux/export.h:43,
  |                  from ./include/linux/linkage.h:7,
  |                  from ./include/linux/kernel.h:8,
  |                  from net/netfilter/core.c:9:
  | net/netfilter/core.c: In function ‘nf_remove_net_hook’:
  | ./include/linux/compiler.h:216:30: warning: assignment discards ‘const’ qualifier from pointer target type [-Wdiscarded-qualifiers]
  |   *(volatile typeof(x) *)&(x) = (val);  \
  |                               ^
  | net/netfilter/core.c:379:3: note: in expansion of macro ‘WRITE_ONCE’
  |    WRITE_ONCE(orig_ops[i], &dummy_ops);
  |    ^~~~~~~~~~

Follow the pattern used elsewhere in this file and add a cast to 'void *'
to squash the warning.

Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Jozsef Kadlecsik <kadlec@netfilter.org>
Cc: Florian Westphal <fw@strlen.de>
Cc: "David S. Miller" <davem@davemloft.net>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-04-15 21:36:41 +01:00
Florian Westphal ca58fbe06c netfilter: add and use nf_hook_slow_list()
At this time, NF_HOOK_LIST() macro will iterate the list and then calls
nf_hook() for each individual skb.

This makes it so the entire list is passed into the netfilter core.
The advantage is that we only need to fetch the rule blob once per list
instead of per-skb.

NF_HOOK_LIST now only works for ipv4 and ipv6, as those are the only
callers.

v2: use skb_list_del_init() instead of list_del (Edward Cree)

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-10-17 12:20:48 +02:00
Florian Westphal 0d9cb300ac netfilter: nf_queue: remove unused hook entries pointer
Its not used anywhere, so remove this.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-07-04 02:29:49 +02:00
Florian Westphal 2cf6bffc49 netfilter: replace skb_make_writable with skb_ensure_writable
This converts all remaining users and then removes skb_make_writable.

Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-05-31 18:02:48 +02:00
Sinan Kaya 432d82200f net: replace CONFIG_DEBUG_KERNEL with CONFIG_DEBUG_MISC
CONFIG_DEBUG_KERNEL should not impact code generation.  Use the newly
defined CONFIG_DEBUG_MISC instead to keep the current code.

Link: http://lkml.kernel.org/r/20190413224438.10802-6-okaya@kernel.org
Signed-off-by: Sinan Kaya <okaya@kernel.org>
Acked-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Florian Westphal <fw@strlen.de>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc:  Chris Zankel <chris@zankel.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Thomas Bogendoerfer <tbogendoerfer@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-05-14 19:52:50 -07:00
Florian Westphal 971502d77f bridge: netfilter: unroll NF_HOOK helper in bridge input path
Replace NF_HOOK() based invocation of the netfilter hooks with a private
copy of nf_hook_slow().

This copy has one difference: it can return the rx handler value expected
by the stack, i.e. RX_HANDLER_CONSUMED or RX_HANDLER_PASS.

This is needed by the next patch to invoke the ebtables
"broute" table via the standard netfilter hooks rather than the custom
"br_should_route_hook" indirection that is used now.

When the skb is to be "brouted", we must return RX_HANDLER_PASS from the
bridge rx input handler, but there is no way to indicate this via
NF_HOOK(), unless perhaps by some hack such as exposing bridge_cb in the
netfilter core or a percpu flag.

  text    data     bss     dec   filename
  3369      56       0    3425   net/bridge/br_input.o.before
  3458      40       0    3498   net/bridge/br_input.o.after

This allows removal of the "br_should_route_hook" in the next patch.

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: David S. Miller <davem@davemloft.net>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2019-04-12 01:47:39 +02:00
Masahiro Yamada e9666d10a5 jump_label: move 'asm goto' support test to Kconfig
Currently, CONFIG_JUMP_LABEL just means "I _want_ to use jump label".

The jump label is controlled by HAVE_JUMP_LABEL, which is defined
like this:

  #if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
  # define HAVE_JUMP_LABEL
  #endif

We can improve this by testing 'asm goto' support in Kconfig, then
make JUMP_LABEL depend on CC_HAS_ASM_GOTO.

Ugly #ifdef HAVE_JUMP_LABEL will go away, and CONFIG_JUMP_LABEL will
match to the real kernel capability.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
2019-01-06 09:46:51 +09:00
Toke Høiland-Jørgensen b60a60405f netfilter: Add nf_ct_get_tuple_skb global lookup function
This adds a global netfilter function to extract a conntrack tuple from an
skb. The function uses a new function added to nf_ct_hook, which will try
to get the tuple from skb->_nfct, and do a full lookup if that fails. This
makes it possible to use the lookup function before the skb has passed
through the conntrack init hooks (e.g., in an ingress qdisc). The tuple is
copied to the caller to avoid issues with reference counting.

The function returns false if conntrack is not loaded, allowing it to be
used without incurring a module dependency on conntrack. This is used by
the NAT mode in sch_cake.

Cc: netfilter-devel@vger.kernel.org
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-10 20:06:34 -07:00
David S. Miller fb83eb93c6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

The following patchset contains Netfilter updates for your net-next
tree, they are:

1) Remove obsolete nf_log tracing from nf_tables, from Florian Westphal.

2) Add support for map lookups to numgen, random and hash expressions,
   from Laura Garcia.

3) Allow to register nat hooks for iptables and nftables at the same
   time. Patchset from Florian Westpha.

4) Timeout support for rbtree sets.

5) ip6_rpfilter works needs interface for link-local addresses, from
   Vincent Bernat.

6) Add nf_ct_hook and nf_nat_hook structures and use them.

7) Do not drop packets on packets raceing to insert conntrack entries
   into hashes, this is particularly a problem in nfqueue setups.

8) Address fallout from xt_osf separation to nf_osf, patches
   from Florian Westphal and Fernando Mancera.

9) Remove reference to struct nft_af_info, which doesn't exist anymore.
   From Taehee Yoo.

This batch comes with is a conflict between 25fd386e0b ("netfilter:
core: add missing __rcu annotation") in your tree and 2c205dd398
("netfilter: add struct nf_nat_hook and use it") coming in this batch.
This conflict can be solved by leaving the __rcu tag on
__netfilter_net_init() - added by 25fd386e0b - and remove all code
related to nf_nat_decode_session_hook - which is gone after
2c205dd398, as described by:

diff --cc net/netfilter/core.c
index e0ae4aae96f5,206fb2c4c319..168af54db975
--- a/net/netfilter/core.c
+++ b/net/netfilter/core.c
@@@ -611,7 -580,13 +611,8 @@@ const struct nf_conntrack_zone nf_ct_zo
  EXPORT_SYMBOL_GPL(nf_ct_zone_dflt);
  #endif /* CONFIG_NF_CONNTRACK */

- static void __net_init __netfilter_net_init(struct nf_hook_entries **e, int max)
 -#ifdef CONFIG_NF_NAT_NEEDED
 -void (*nf_nat_decode_session_hook)(struct sk_buff *, struct flowi *);
 -EXPORT_SYMBOL(nf_nat_decode_session_hook);
 -#endif
 -
+ static void __net_init
+ __netfilter_net_init(struct nf_hook_entries __rcu **e, int max)
  {
  	int h;

I can also merge your net-next tree into nf-next, solve the conflict and
resend the pull request if you prefer so.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-23 16:37:11 -04:00
Pablo Neira Ayuso 2c205dd398 netfilter: add struct nf_nat_hook and use it
Move decode_session() and parse_nat_setup_hook() indirections to struct
nf_nat_hook structure.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-05-23 09:26:07 +02:00
Pablo Neira Ayuso 1f4b24397d netfilter: add struct nf_ct_hook and use it
Move the nf_ct_destroy indirection to the struct nf_ct_hook.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-05-23 09:26:06 +02:00
Florian Westphal a37061a678 netfilter: lift one-nat-hook-only restriction
This reverts commit f92b40a8b2
("netfilter: core: only allow one nat hook per hook point"), this
limitation is no longer needed.  The nat core now invokes these
functions and makes sure that hook evaluation stops after a mapping is
created and a null binding is created otherwise.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-05-23 09:14:06 +02:00
Florian Westphal 06cad3acf0 netfilter: core: export raw versions of add/delete hook functions
This will allow the nat core to reuse the nf_hook infrastructure
to maintain nat lookup functions.

The raw versions don't assume a particular hook location, the
functions get added/deleted from the hook blob that is passed to the
functions.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-05-23 09:14:05 +02:00
Florian Westphal 25fd386e0b netfilter: core: add missing __rcu annotation
removes following sparse error:
net/netfilter/core.c:598:30: warning: incorrect type in argument 1 (different address spaces)
net/netfilter/core.c:598:30:    expected struct nf_hook_entries **e
net/netfilter/core.c:598:30:    got struct nf_hook_entries [noderef] <asn:4>**<noident>

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-05-08 14:15:30 +02:00
Pablo Neira Ayuso cbef426ce7 netfilter: core: return EBUSY in case NAT hook is already in use
EEXIST is used for an object that already exists, with the same
name/handle. However, there no same object there, instead there is a
object that is using the single slot that is available for NAT hooks
since patch f92b40a8b2 ("netfilter: core: only allow one nat hook per
hook point"). Let's change this return value before this behaviour gets
exposed in the first -rc.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-10 15:32:16 +01:00
Wei Yongjun 0ded1785f3 netfilter: core: make local function __nf_unregister_net_hook static
Fixes the following sparse warning:

net/netfilter/core.c:380:6: warning:
 symbol '__nf_unregister_net_hook' was not declared. Should it be static?

Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-10 15:32:14 +01:00
Pablo Neira Ayuso b3a61254d8 netfilter: remove struct nf_afinfo and its helper functions
This abstraction has no clients anymore, remove it.

This is what remains from previous authors, so correct copyright
statement after recent modifications and code removal.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:11:02 +01:00
Pablo Neira Ayuso cb7ccd835e netfilter: core: support for NFPROTO_INET hook registration
Expand NFPROTO_INET in two hook registrations, one for NFPROTO_IPV4 and
another for NFPROTO_IPV6. Hence, we handle NFPROTO_INET from the core.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:19 +01:00
Pablo Neira Ayuso 3025940811 netfilter: core: pass family as parameter to nf_remove_net_hook()
So static_key_slow_dec applies to the family behind NFPROTO_INET.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:19 +01:00
Pablo Neira Ayuso 62a0fe46e2 netfilter: core: pass hook number, family and device to nf_find_hook_list()
Instead of passing struct nf_hook_ops, this is needed by follow up
patches to handle NFPROTO_INET from the core.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:18 +01:00
Pablo Neira Ayuso 3d3cdc38e8 netfilter: core: add nf_remove_net_hook
Just a cleanup, __nf_unregister_net_hook() is used by a follow up patch
when handling NFPROTO_INET as a real family from the core.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:17 +01:00
Florian Westphal f92b40a8b2 netfilter: core: only allow one nat hook per hook point
The netfilter NAT core cannot deal with more than one NAT hook per hook
location (prerouting, input ...), because the NAT hooks install a NAT null
binding in case the iptables nat table (iptable_nat hooks) or the
corresponding nftables chain (nft nat hooks) doesn't specify a nat
transformation.

Null bindings are needed to detect port collsisions between NAT-ed and
non-NAT-ed connections.

This causes nftables NAT rules to not work when iptable_nat module is
loaded, and vice versa because nat binding has already been attached
when the second nat hook is consulted.

The netfilter core is not really the correct location to handle this
(hooks are just hooks, the core has no notion of what kinds of side
 effects a hook implements), but its the only place where we can check
for conflicts between both iptables hooks and nftables hooks without
adding dependencies.

So add nat annotation to hook_ops to describe those hooks that will
add NAT bindings and then make core reject if such a hook already exists.
The annotation fills a padding hole, in case further restrictions appar
we might change this to a 'u8 type' instead of bool.

iptables error if nft nat hook active:
iptables -t nat -A POSTROUTING -j MASQUERADE
iptables v1.4.21: can't initialize iptables table `nat': File exists
Perhaps iptables or your kernel needs to be upgraded.

nftables error if iptables nat table present:
nft -f /etc/nftables/ipv4-nat
/usr/etc/nftables/ipv4-nat:3:1-2: Error: Could not process rule: File exists
table nat {
^^

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:13 +01:00
Florian Westphal 2a95183a5e netfilter: don't allocate space for arp/bridge hooks unless needed
no need to define hook points if the family isn't supported.
Because we need these hooks for either nftables, arp/ebtables
or the 'call-iptables' hack we have in the bridge layer add two
new dependencies, NETFILTER_FAMILY_{ARP,BRIDGE}, and have the
users select them.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:11 +01:00
Florian Westphal bb4badf3a3 netfilter: don't allocate space for decnet hooks unless needed
no need to define hook points if the family isn't supported.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:10 +01:00
Florian Westphal ef57170bbf netfilter: reduce hook array sizes to what is needed
Not all families share the same hook count, adjust sizes to what is
needed.

struct net before:
/* size: 6592, cachelines: 103, members: 46 */
after:
/* size: 5952, cachelines: 93, members: 46 */

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:09 +01:00
Florian Westphal b0f38338ae netfilter: reduce size of hook entry point locations
struct net contains:

struct nf_hook_entries __rcu *hooks[NFPROTO_NUMPROTO][NF_MAX_HOOKS];

which store the hook entry point locations for the various protocol
families and the hooks.

Using array results in compact c code when doing accesses, i.e.
  x = rcu_dereference(net->nf.hooks[pf][hook]);

but its also wasting a lot of memory, as most families are
not used.

So split the array into those families that are used, which
are only 5 (instead of 13).  In most cases, the 'pf' argument is
constant, i.e. gcc removes switch statement.

struct net before:
 /* size: 5184, cachelines: 81, members: 46 */
after:
 /* size: 4672, cachelines: 73, members: 46 */

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:08 +01:00
Florian Westphal 8c873e2199 netfilter: core: free hooks with call_rcu
Giuseppe Scrivano says:
  "SELinux, if enabled, registers for each new network namespace 6
    netfilter hooks."

Cost for this is high.  With synchronize_net() removed:
   "The net benefit on an SMP machine with two cores is that creating a
   new network namespace takes -40% of the original time."

This patch replaces synchronize_net+kvfree with call_rcu().
We store rcu_head at the tail of a structure that has no fixed layout,
i.e. we cannot use offsetof() to compute the start of the original
allocation.  Thus store this information right after the rcu head.

We could simplify this by just placing the rcu_head at the start
of struct nf_hook_entries.  However, this structure is used in
packet processing hotpath, so only place what is needed for that
at the beginning of the struct.

Reported-by: Giuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:07 +01:00
Florian Westphal 26888dfd7e netfilter: core: remove synchronize_net call if nfqueue is used
since commit 960632ece6 ("netfilter: convert hook list to an array")
nfqueue no longer stores a pointer to the hook that caused the packet
to be queued.  Therefore no extra synchronize_net() call is needed after
dropping the packets enqueued by the old rule blob.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:06 +01:00
Florian Westphal 4e645b47c4 netfilter: core: make nf_unregister_net_hooks simple wrapper again
This reverts commit d3ad2c17b4
("netfilter: core: batch nf_unregister_net_hooks synchronize_net calls").

Nothing wrong with it.  However, followup patch will delay freeing of hooks
with call_rcu, so all synchronize_net() calls become obsolete and there
is no need anymore for this batching.

This revert causes a temporary performance degradation when destroying
network namespace, but its resolved with the upcoming call_rcu conversion.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2018-01-08 18:01:05 +01:00
Florian Westphal 74585d4f84 netfilter: core: remove erroneous warn_on
kernel test robot reported:

WARNING: CPU: 0 PID: 1244 at net/netfilter/core.c:218 __nf_hook_entries_try_shrink+0x49/0xcd
[..]

After allowing batching in nf_unregister_net_hooks its possible that an earlier
call to __nf_hook_entries_try_shrink already compacted the list.
If this happens we don't need to do anything.

Fixes: d3ad2c17b4 ("netfilter: core: batch nf_unregister_net_hooks synchronize_net calls")
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-09-08 18:55:52 +02:00
Florian Westphal d3ad2c17b4 netfilter: core: batch nf_unregister_net_hooks synchronize_net calls
re-add batching in nf_unregister_net_hooks().

Similar as before, just store an array with to-be-free'd rule arrays
on stack, then call synchronize_net once per batch.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-28 17:44:02 +02:00
Florian Westphal 2420b79f8c netfilter: debug: check for sorted array
Make sure our grow/shrink routine places them in the correct order.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-28 17:44:01 +02:00
Aaron Conole 960632ece6 netfilter: convert hook list to an array
This converts the storage and layout of netfilter hook entries from a
linked list to an array.  After this commit, hook entries will be
stored adjacent in memory.  The next pointer is no longer required.

The ops pointers are stored at the end of the array as they are only
used in the register/unregister path and in the legacy br_netfilter code.

nf_unregister_net_hooks() is slower than needed as it just calls
nf_unregister_net_hook in a loop (i.e. at least n synchronize_net()
calls), this will be addressed in followup patch.

Test setup:
 - ixgbe 10gbit
 - netperf UDP_STREAM, 64 byte packets
 - 5 hooks: (raw + mangle prerouting, mangle+filter input, inet filter):
empty mangle and raw prerouting, mangle and filter input hooks:
353.9
this patch:
364.2

Signed-off-by: Aaron Conole <aconole@bytheb.org>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-08-28 17:44:00 +02:00
Dan Carpenter 073dd5ad34 netfilter: fix netfilter_net_init() return
We accidentally return an uninitialized variable.

Fixes: cf56c2f892 ("netfilter: remove old pre-netns era hook api")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-18 14:50:28 -07:00
Florian Westphal cf56c2f892 netfilter: remove old pre-netns era hook api
no more users in the tree, remove this.

The old api is racy wrt. module removal, all users have been converted
to the netns-aware api.

The old api pretended we still have global hooks but that has not been
true for a long time.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-07-17 17:01:10 +02:00
Florian Westphal 039b40ee58 netfilter: nf_queue: only call synchronize_net twice if nf_queue is active
nf_unregister_net_hook(s) can avoid a second call to synchronize_net,
provided there is no nfqueue active in that net namespace (which is
the common case).

This also gets rid of the extra arg to nf_queue_nf_hook_drop(), normally
this gets called during netns cleanup so no packets should be queued.

For the rare case of base chain being unregistered or module removal
while nfqueue is in use the extra hiccup due to the packet drops isn't
a big deal.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-01 11:19:12 +02:00
Florian Westphal 933bd83ed6 netfilter: batch synchronize_net calls during hook unregister
synchronize_net is expensive and slows down netns cleanup a lot.

We have two APIs to unregister a hook:
nf_unregister_net_hook (which calls synchronize_net())
and
nf_unregister_net_hooks (calls nf_unregister_net_hook in a loop)

Make nf_unregister_net_hook a wapper around new helper
__nf_unregister_net_hook, which unlinks the hook but does not free it.

Then, we can call that helper in nf_unregister_net_hooks and then
call synchronize_net() only once.

Andrey Konovalov reports this change improves syzkaller fuzzing speed at
least twice.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-05-01 11:18:54 +02:00
Florian Westphal a9e419dc7b netfilter: merge ctinfo into nfct pointer storage area
After this change conntrack operations (lookup, creation, matching from
ruleset) only access one instead of two sk_buff cache lines.

This works for normal conntracks because those are allocated from a slab
that guarantees hw cacheline or 8byte alignment (whatever is larger)
so the 3 bits needed for ctinfo won't overlap with nf_conn addresses.

Template allocation now does manual address alignment (see previous change)
on arches that don't have sufficent kmalloc min alignment.

Some spots intentionally use skb->_nfct instead of skb_nfct() helpers,
this is to avoid undoing the skb_nfct() use when we remove untracked
conntrack object in the future.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2017-02-02 14:31:56 +01:00