Commit graph

6032 commits

Author SHA1 Message Date
wenxu
97629b237a netfilter: flowtable: fix nft_flow_route source address for nat case
For snat and dnat cases, the saddr should be taken from reverse tuple.

Fixes: 3412e16418 (netfilter: flowtable: nft_flow_route use more data for reverse route)
Signed-off-by: wenxu <wenxu@chinatelecom.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-31 23:32:53 +02:00
wenxu
f1896d45fe netfilter: flowtable: fix missing FLOWI_FLAG_ANYSRC flag
The nf_flow_table gets route through ip_route_output_key. If the saddr
is not local one, then FLOWI_FLAG_ANYSRC flag should be set. Without
this flag, the route lookup for other_dst will fail.

Fixes: 3412e16418 (netfilter: flowtable: nft_flow_route use more data for reverse route)
Signed-off-by: wenxu <wenxu@chinatelecom.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-31 23:14:03 +02:00
Pablo Neira Ayuso
f9a43007d3 netfilter: nf_tables: double hook unregistration in netns path
__nft_release_hooks() is called from pre_netns exit path which
unregisters the hooks, then the NETDEV_UNREGISTER event is triggered
which unregisters the hooks again.

[  565.221461] WARNING: CPU: 18 PID: 193 at net/netfilter/core.c:495 __nf_unregister_net_hook+0x247/0x270
[...]
[  565.246890] CPU: 18 PID: 193 Comm: kworker/u64:1 Tainted: G            E     5.18.0-rc7+ #27
[  565.253682] Workqueue: netns cleanup_net
[  565.257059] RIP: 0010:__nf_unregister_net_hook+0x247/0x270
[...]
[  565.297120] Call Trace:
[  565.300900]  <TASK>
[  565.304683]  nf_tables_flowtable_event+0x16a/0x220 [nf_tables]
[  565.308518]  raw_notifier_call_chain+0x63/0x80
[  565.312386]  unregister_netdevice_many+0x54f/0xb50

Unregister and destroy netdev hook from netns pre_exit via kfree_rcu
so the NETDEV_UNREGISTER path see unregistered hooks.

Fixes: 767d1216bf ("netfilter: nftables: fix possible UAF over chains from packet path in netns")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-31 23:13:10 +02:00
Pablo Neira Ayuso
3923b1e440 netfilter: nf_tables: hold mutex on netns pre_exit path
clean_net() runs in workqueue while walking over the lists, grab mutex.

Fixes: 767d1216bf ("netfilter: nftables: fix possible UAF over chains from packet path in netns")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-31 23:13:10 +02:00
Pablo Neira Ayuso
fecf31ee39 netfilter: nf_tables: sanitize nft_set_desc_concat_parse()
Add several sanity checks for nft_set_desc_concat_parse():

- validate desc->field_count not larger than desc->field_len array.
- field length cannot be larger than desc->field_len (ie. U8_MAX)
- total length of the concatenation cannot be larger than register array.

Joint work with Florian Westphal.

Fixes: f3a2181e16 ("netfilter: nf_tables: Support for sets with multiple ranged fields")
Reported-by: <zhangziming.zzm@antgroup.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-31 23:13:10 +02:00
Pablo Neira Ayuso
b53c116642 netfilter: nf_tables: set element extended ACK reporting support
Report the element that causes problems via netlink extended ACK for set
element commands.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-27 11:16:38 +02:00
Florian Westphal
aeed55a08d netfilter: cttimeout: fix slab-out-of-bounds read in cttimeout_net_exit
syzbot reports:
BUG: KASAN: slab-out-of-bounds in __list_del_entry_valid+0xcc/0xf0 lib/list_debug.c:42
[..]
 list_del include/linux/list.h:148 [inline]
 cttimeout_net_exit+0x211/0x540 net/netfilter/nfnetlink_cttimeout.c:617

No reproducer so far. Looking at recent changes in this area
its clear that the free_head must not be at the end of the
structure because nf_ct_timeout structure has variable size.

Reported-by: <syzbot+92968395eedbdbd3617d@syzkaller.appspotmail.com>
Fixes: 78222bacfc ("netfilter: cttimeout: decouple unlink and free on netns destruction")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-27 11:16:38 +02:00
Florian Westphal
ffd219efd9 netfilter: nfnetlink: fix warn in nfnetlink_unbind
syzbot reports following warn:
WARNING: CPU: 0 PID: 3600 at net/netfilter/nfnetlink.c:703 nfnetlink_unbind+0x357/0x3b0 net/netfilter/nfnetlink.c:694

The syzbot generated program does this:

socket(AF_NETLINK, SOCK_RAW, NETLINK_NETFILTER) = 3
setsockopt(3, SOL_NETLINK, NETLINK_DROP_MEMBERSHIP, [1], 4) = 0

... which triggers 'WARN_ON_ONCE(nfnlnet->ctnetlink_listeners == 0)' check.

Instead of counting, just enable reporting for every bind request
and check if we still have listeners on unbind.

While at it, also add the needed bounds check on nfnl_group2type[]
access.

Reported-by: <syzbot+4903218f7fba0a2d6226@syzkaller.appspotmail.com>
Reported-by: <syzbot+afd2d80e495f96049571@syzkaller.appspotmail.com>
Fixes: 2794cdb0b9 ("netfilter: nfnetlink: allow to detect if ctnetlink listeners exist")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-27 11:16:33 +02:00
Phil Sutter
558254b0b6 netfilter: nft_limit: Clone packet limits' cost value
When cloning a packet-based limit expression, copy the cost value as
well. Otherwise the new limit is not functional anymore.

Fixes: 3b9e2ea6c1 ("netfilter: nft_limit: move stateful fields out of expression data")
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-26 22:50:34 +02:00
Pablo Neira Ayuso
520778042c netfilter: nf_tables: disallow non-stateful expression in sets earlier
Since 3e135cd499 ("netfilter: nft_dynset: dynamic stateful expression
instantiation"), it is possible to attach stateful expressions to set
elements.

cd5125d8f5 ("netfilter: nf_tables: split set destruction in deactivate
and destroy phase") introduces conditional destruction on the object to
accomodate transaction semantics.

nft_expr_init() calls expr->ops->init() first, then check for
NFT_STATEFUL_EXPR, this stills allows to initialize a non-stateful
lookup expressions which points to a set, which might lead to UAF since
the set is not properly detached from the set->binding for this case.
Anyway, this combination is non-sense from nf_tables perspective.

This patch fixes this problem by checking for NFT_STATEFUL_EXPR before
expr->ops->init() is called.

The reporter provides a KASAN splat and a poc reproducer (similar to
those autogenerated by syzbot to report use-after-free errors). It is
unknown to me if they are using syzbot or if they use similar automated
tool to locate the bug that they are reporting.

For the record, this is the KASAN splat.

[   85.431824] ==================================================================
[   85.432901] BUG: KASAN: use-after-free in nf_tables_bind_set+0x81b/0xa20
[   85.433825] Write of size 8 at addr ffff8880286f0e98 by task poc/776
[   85.434756]
[   85.434999] CPU: 1 PID: 776 Comm: poc Tainted: G        W         5.18.0+ #2
[   85.436023] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014

Fixes: 0b2d8a7b63 ("netfilter: nf_tables: add helper functions for expression handling")
Reported-and-tested-by: Aaron Adams <edg-e@nccgroup.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-26 22:50:33 +02:00
Jakub Kicinski
805cb5aadc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next
Pablo Neira Ayuso says:

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

The following patchset contains Netfilter updates for net-next, misc
updates and fallout fixes from recent Florian's code rewritting (from
last pull request):

1) Use new flowi4_l3mdev field in ip_route_me_harder(), from Martin Willi.

2) Avoid unnecessary GC with a timestamp in conncount, from William Tu
   and Yifeng Sun.

3) Remove TCP conntrack debugging, from Florian Westphal.

4) Fix compilation warning in ctnetlink, from Florian.

* git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: ctnetlink: fix up for "netfilter: conntrack: remove unconfirmed list"
  netfilter: conntrack: remove pr_debug callsites from tcp tracker
  netfilter: nf_conncount: reduce unnecessary GC
  netfilter: Use l3mdev flow key when re-routing mangled packets
====================

Link: https://lore.kernel.org/r/20220519220206.722153-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-19 21:53:08 -07:00
Jakub Kicinski
d7e6f58360 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/ethernet/mellanox/mlx5/core/main.c
  b33886971d ("net/mlx5: Initialize flow steering during driver probe")
  40379a0084 ("net/mlx5_fpga: Drop INNOVA TLS support")
  f2b41b32cd ("net/mlx5: Remove ipsec_ops function table")
https://lore.kernel.org/all/20220519040345.6yrjromcdistu7vh@sx1/
  16d42d3133 ("net/mlx5: Drain fw_reset when removing device")
  8324a02c34 ("net/mlx5: Add exit route when waiting for FW")
https://lore.kernel.org/all/20220519114119.060ce014@canb.auug.org.au/

tools/testing/selftests/net/mptcp/mptcp_join.sh
  e274f71540 ("selftests: mptcp: add subflow limits test-cases")
  b6e074e171 ("selftests: mptcp: add infinite map testcase")
  5ac1d2d634 ("selftests: mptcp: Add tests for userspace PM type")
https://lore.kernel.org/all/20220516111918.366d747f@canb.auug.org.au/

net/mptcp/options.c
  ba2c89e0ea ("mptcp: fix checksum byte order")
  1e39e5a32a ("mptcp: infinite mapping sending")
  ea66758c17 ("tcp: allow MPTCP to update the announced window")
https://lore.kernel.org/all/20220519115146.751c3a37@canb.auug.org.au/

net/mptcp/pm.c
  95d6865178 ("mptcp: fix subflow accounting on close")
  4d25247d3a ("mptcp: bypass in-kernel PM restrictions for non-kernel PMs")
https://lore.kernel.org/all/20220516111435.72f35dca@canb.auug.org.au/

net/mptcp/subflow.c
  ae66fb2ba6 ("mptcp: Do TCP fallback on early DSS checksum failure")
  0348c690ed ("mptcp: add the fallback check")
  f8d4bcacff ("mptcp: infinite mapping receiving")
https://lore.kernel.org/all/20220519115837.380bb8d4@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-05-19 11:23:59 -07:00
Pablo Neira Ayuso
9e539c5b6d netfilter: nf_tables: disable expression reduction infra
Either userspace or kernelspace need to pre-fetch keys inconditionally
before comparisons for this to work. Otherwise, register tracking data
is misleading and it might result in reducing expressions which are not
yet registers.

First expression is also guaranteed to be evaluated always, however,
certain expressions break before writing data to registers, before
comparing the data, leaving the register in undetermined state.

This patch disables this infrastructure by now.

Fixes: b2d306542f ("netfilter: nf_tables: do not reduce read-only expressions")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-18 17:34:26 +02:00
Ritaro Takenaka
2738d9d963 netfilter: flowtable: move dst_check to packet path
Fixes sporadic IPv6 packet loss when flow offloading is enabled.

IPv6 route GC and flowtable GC are not synchronized.
When dst_cache becomes stale and a packet passes through the flow before
the flowtable GC teardowns it, the packet can be dropped.
So, it is necessary to check dst every time in packet path.

Fixes: 227e1e4d0d ("netfilter: nf_flowtable: skip device lookup from interface index")
Signed-off-by: Ritaro Takenaka <ritarot634@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-18 17:34:26 +02:00
Pablo Neira Ayuso
e5eaac2beb netfilter: flowtable: fix TCP flow teardown
This patch addresses three possible problems:

1. ct gc may race to undo the timeout adjustment of the packet path, leaving
   the conntrack entry in place with the internal offload timeout (one day).

2. ct gc removes the ct because the IPS_OFFLOAD_BIT is not set and the CLOSE
   timeout is reached before the flow offload del.

3. tcp ct is always set to ESTABLISHED with a very long timeout
   in flow offload teardown/delete even though the state might be already
   CLOSED. Also as a remark we cannot assume that the FIN or RST packet
   is hitting flow table teardown as the packet might get bumped to the
   slow path in nftables.

This patch resets IPS_OFFLOAD_BIT from flow_offload_teardown(), so
conntrack handles the tcp rst/fin packet which triggers the CLOSE/FIN
state transition.

Moreover, teturn the connection's ownership to conntrack upon teardown
by clearing the offload flag and fixing the established timeout value.
The flow table GC thread will asynchonrnously free the flow table and
hardware offload entries.

Before this patch, the IPS_OFFLOAD_BIT remained set for expired flows on
which is also misleading since the flow is back to classic conntrack
path.

If nf_ct_delete() removes the entry from the conntrack table, then it
calls nf_ct_put() which decrements the refcnt. This is not a problem
because the flowtable holds a reference to the conntrack object from
flow_offload_alloc() path which is released via flow_offload_free().

This patch also updates nft_flow_offload to skip packets in SYN_RECV
state. Since we might miss or bump packets to slow path, we do not know
what will happen there while we are still in SYN_RECV, this patch
postpones offload up to the next packet which also aligns to the
existing behaviour in tc-ct.

flow_offload_teardown() does not reset the existing tcp state from
flow_offload_fixup_tcp() to ESTABLISHED anymore, packets bump to slow
path might have already update the state to CLOSE/FIN.

Joint work with Oz and Sven.

Fixes: 1e5b2471bc ("netfilter: nf_flow_table: teardown flow timeout race")
Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Signed-off-by: Sven Auhagen <sven.auhagen@voleatech.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-18 17:34:26 +02:00
Stephen Rothwell
58a94a62a5 netfilter: ctnetlink: fix up for "netfilter: conntrack: remove unconfirmed list"
After merging the net-next tree, today's linux-next build (powerpc
ppc64_defconfig) produced this warning:

nf_conntrack_netlink.c:1717 warning: 'ctnetlink_dump_one_entry' defined but not used

Fixes: 8a75a2c174 ("netfilter: conntrack: remove unconfirmed list")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Florian Westphal <fw@strlen.de>
2022-05-18 09:21:59 +02:00
Florian Westphal
f74360d344 netfilter: conntrack: remove pr_debug callsites from tcp tracker
They are either obsolete or useless.

Those in the normal processing path cannot be enabled on a production
system; they generate too much noise.

One pr_debug call resides in an error path and does provide useful info,
merge it with the existing nf_log_invalid().

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-16 13:09:51 +02:00
William Tu
d265929930 netfilter: nf_conncount: reduce unnecessary GC
Currently nf_conncount can trigger garbage collection (GC)
at multiple places. Each GC process takes a spin_lock_bh
to traverse the nf_conncount_list. We found that when testing
port scanning use two parallel nmap, because the number of
connection increase fast, the nf_conncount_count and its
subsequent call to __nf_conncount_add take too much time,
causing several CPU lockup. This happens when user set the
conntrack limit to +20,000, because the larger the limit,
the longer the list that GC has to traverse.

The patch mitigate the performance issue by avoiding unnecessary
GC with a timestamp. Whenever nf_conncount has done a GC,
a timestamp is updated, and beforce the next time GC is
triggered, we make sure it's more than a jiffies.
By doin this we can greatly reduce the CPU cycles and
avoid the softirq lockup.

To reproduce it in OVS,
$ ovs-appctl dpctl/ct-set-limits zone=1,limit=20000
$ ovs-appctl dpctl/ct-get-limits

At another machine, runs two nmap
$ nmap -p1- <IP>
$ nmap -p1- <IP>

Signed-off-by: William Tu <u9012063@gmail.com>
Co-authored-by: Yifeng Sun <pkusunyifeng@gmail.com>
Reported-by: Greg Rose <gvrose8192@gmail.com>
Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-16 13:05:40 +02:00
Felix Fietkau
2456074935 netfilter: nft_flow_offload: fix offload with pppoe + vlan
When running a combination of PPPoE on top of a VLAN, we need to set
info->outdev to the PPPoE device, otherwise PPPoE encap is skipped
during software offload.

Fixes: 72efd585f7 ("netfilter: flowtable: add pppoe support")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-16 12:58:55 +02:00
Felix Fietkau
45ca3e6199 netfilter: nft_flow_offload: skip dst neigh lookup for ppp devices
The dst entry does not contain a valid hardware address, so skip the lookup
in order to avoid running into errors here.
The proper hardware address is filled in from nft_dev_path_info

Fixes: 72efd585f7 ("netfilter: flowtable: add pppoe support")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-16 12:58:55 +02:00
Felix Fietkau
396ef64113 netfilter: flowtable: fix excessive hw offload attempts after failure
If a flow cannot be offloaded, the code currently repeatedly tries again as
quickly as possible, which can significantly increase system load.
Fix this by limiting flow timeout update and hardware offload retry to once
per second.

Fixes: c07531c01d ("netfilter: flowtable: Remove redundant hw refresh bit")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-16 12:58:55 +02:00
David S. Miller
1a01a07517 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next
Pablo Neira Ayuso says:

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

This is v2 including deadlock fix in conntrack ecache rework
reported by Jakub Kicinski.

The following patchset contains Netfilter updates for net-next,
mostly updates to conntrack from Florian Westphal.

1) Add a dedicated list for conntrack event redelivery.

2) Include event redelivery list in conntrack dumps of dying type.

3) Remove per-cpu dying list for event redelivery, not used anymore.

4) Add netns .pre_exit to cttimeout to zap timeout objects before
   synchronize_rcu() call.

5) Remove nf_ct_unconfirmed_destroy.

6) Add generation id for conntrack extensions for conntrack
   timeout and helpers.

7) Detach timeout policy from conntrack on cttimeout module removal.

8) Remove __nf_ct_unconfirmed_destroy.

9) Remove unconfirmed list.

10) Remove unconditional local_bh_disable in init_conntrack().

11) Consolidate conntrack iterator nf_ct_iterate_cleanup().

12) Detect if ctnetlink listeners exist to short-circuit event
    path early.

13) Un-inline nf_ct_ecache_ext_add().

14) Add nf_conntrack_events autodetect ctnetlink listener mode
    and make it default.

15) Add nf_ct_ecache_exist() to check for event cache extension.

16) Extend flowtable reverse route lookup to include source, iif,
    tos and mark, from Sven Auhagen.

17) Do not verify zero checksum UDP packets in nf_reject,
    from Kevin Mitchell.

====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2022-05-16 10:10:37 +01:00
Sven Auhagen
3412e16418 netfilter: flowtable: nft_flow_route use more data for reverse route
When creating a flow table entry, the reverse route is looked
up based on the current packet.
There can be scenarios where the user creates a custom ip rule
to route the traffic differently.
In order to support those scenarios, the lookup needs to add
more information based on the current packet.
The patch adds multiple new information to the route lookup.

Signed-off-by: Sven Auhagen <sven.auhagen@voleatech.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:56:28 +02:00
Florian Westphal
90d1daa458 netfilter: conntrack: add nf_conntrack_events autodetect mode
This adds the new nf_conntrack_events=2 mode and makes it the
default.

This leverages the earlier flag in struct net to allow to avoid
the event extension as long as no event listener is active in
the namespace.

This avoids, for most cases, allocation of ct->ext area.
A followup patch will take further advantage of this by avoiding
calls down into the event framework if the extension isn't present.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:56:28 +02:00
Florian Westphal
b0a7ab4a77 netfilter: conntrack: un-inline nf_ct_ecache_ext_add
Only called when new ct is allocated or the extension isn't present.
This function will be extended, place this in the conntrack module
instead of inlining.

The callers already depend on nf_conntrack module.
Return value is changed to bool, noone used the returned pointer.

Make sure that the core drops the newly allocated conntrack
if the extension is requested but can't be added.
This makes it necessary to ifdef the section, as the stub
always returns false we'd drop every new conntrack if the
the ecache extension is disabled in kconfig.

Add from data path (xt_CT, nft_ct) is unchanged.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:56:28 +02:00
Florian Westphal
2794cdb0b9 netfilter: nfnetlink: allow to detect if ctnetlink listeners exist
At this time, every new conntrack gets the 'event cache extension'
enabled for it.

This is because the 'net.netfilter.nf_conntrack_events' sysctl defaults
to 1.

Changing the default to 0 means that commands that rely on the event
notification extension, e.g. 'conntrack -E' or conntrackd, stop working.

We COULD detect if there is a listener by means of
'nfnetlink_has_listeners()' and only add the extension if this is true.

The downside is a dependency from conntrack module to nfnetlink module.

This adds a different way: inc/dec a counter whenever a ctnetlink group
is being (un)subscribed and toggle a flag in struct net.

Next patches will take advantage of this and will only add the event
extension if the flag is set.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:56:28 +02:00
Pablo Neira Ayuso
8169ff5840 netfilter: conntrack: add nf_ct_iter_data object for nf_ct_iterate_cleanup*()
This patch adds a structure to collect all the context data that is
passed to the cleanup iterator.

 struct nf_ct_iter_data {
       struct net *net;
       void *data;
       u32 portid;
       int report;
 };

There is a netns field that allows to clean up conntrack entries
specifically owned by the specified netns.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:56:27 +02:00
Florian Westphal
0bcfbafbcd netfilter: conntrack: avoid unconditional local_bh_disable
Now that the conntrack entry isn't placed on the pcpu list anymore the
bh only needs to be disabled in the 'expectation present' case.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:56:27 +02:00
Florian Westphal
8a75a2c174 netfilter: conntrack: remove unconfirmed list
It has no function anymore and can be removed.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:53:27 +02:00
Florian Westphal
ace53fdc26 netfilter: conntrack: remove __nf_ct_unconfirmed_destroy
Its not needed anymore:

A. If entry is totally new, then the rcu-protected resource
must already have been removed from global visibility before call
to nf_ct_iterate_destroy.

B. If entry was allocated before, but is not yet in the hash table
   (uncofirmed case), genid gets incremented and synchronize_rcu() call
   makes sure access has completed.

C. Next attempt to peek at extension area will fail for unconfirmed
  conntracks, because ext->genid != genid.

D. Conntracks in the hash are iterated as before.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:52:17 +02:00
Florian Westphal
42df4fb9b1 netfilter: cttimeout: decouple unlink and free on netns destruction
Increment the extid on module removal; this makes sure that even
in extreme cases any old uncofirmed entry that happened to be kept
e.g. on nfnetlink_queue list will not trip over a stale timeout
reference.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:52:16 +02:00
Florian Westphal
c56716c69c netfilter: extensions: introduce extension genid count
Multiple netfilter extensions store pointers to external data
in their extension area struct.

Examples:
1. Timeout policies
2. Connection tracking helpers.

No references are taken for these.

When a helper or timeout policy is removed, the conntrack table gets
traversed and affected extensions are cleared.

Conntrack entries not yet in the hashtable are referenced via a special
list, the unconfirmed list.

On removal of a policy or connection tracking helper, the unconfirmed
list gets traversed an all entries are marked as dying, this prevents
them from getting committed to the table at insertion time: core checks
for dying bit, if set, the conntrack entry gets destroyed at confirm
time.

The disadvantage is that each new conntrack has to be added to the percpu
unconfirmed list, and each insertion needs to remove it from this list.
The list is only ever needed when a policy or helper is removed -- a rare
occurrence.

Add a generation ID count: Instead of adding to the list and then
traversing that list on policy/helper removal, increment a counter
that is stored in the extension area.

For unconfirmed conntracks, the extension has the genid valid at ct
allocation time.

Removal of a helper/policy etc. increments the counter.
At confirmation time, validate that ext->genid == global_id.

If the stored number is not the same, do not allow the conntrack
insertion, just like as if a confirmed-list traversal would have flagged
the entry as dying.

After insertion, the genid is no longer relevant (conntrack entries
are now reachable via the conntrack table iterators and is set to 0.

This allows removal of the percpu unconfirmed list.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:52:16 +02:00
Florian Westphal
17438b42ce netfilter: remove nf_ct_unconfirmed_destroy helper
This helper tags connections not yet in the conntrack table as
dying.  These nf_conn entries will be dropped instead when the
core attempts to insert them from the input or postrouting
'confirm' hook.

After the previous change, the entries get unlinked from the
list earlier, so that by the time the actual exit hook runs,
new connections no longer have a timeout policy assigned.

Its enough to walk the hashtable instead.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:52:16 +02:00
Florian Westphal
78222bacfc netfilter: cttimeout: decouple unlink and free on netns destruction
Make it so netns pre_exit unlinks the objects from the pernet list, so
they cannot be found anymore.

netns core issues a synchronize_rcu() before calling the exit hooks so
any the time the exit hooks run unconfirmed nf_conn entries have been
free'd or they have been committed to the hashtable.

The exit hook still tags unconfirmed entries as dying, this can
now be removed in a followup change.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:52:16 +02:00
Florian Westphal
1397af5bfd netfilter: conntrack: remove the percpu dying list
Its no longer needed. Entries that need event redelivery are placed
on the new pernet dying list.

The advantage is that there is no need to take additional spinlock on
conntrack removal unless event redelivery failed or the conntrack entry
was never added to the table in the first place (confirmed bit not set).

The IPS_CONFIRMED bit now needs to be set as soon as the entry has been
unlinked from the unconfirmed list, else the destroy function may
attempt to unlink it a second time.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:52:16 +02:00
Florian Westphal
0d3cc504ba netfilter: conntrack: include ecache dying list in dumps
The new pernet dying list includes conntrack entries that await
delivery of the 'destroy' event via ctnetlink.

The old percpu dying list will be removed soon.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:52:16 +02:00
Florian Westphal
2ed3bf188b netfilter: ecache: use dedicated list for event redelivery
This disentangles event redelivery and the percpu dying list.

Because entries are now stored on a dedicated list, all
entries are in NFCT_ECACHE_DESTROY_FAIL state and all entries
still have confirmed bit set -- the reference count is at least 1.

The 'struct net' back-pointer can be removed as well.

The pcpu dying list will be removed eventually, it has no functionality.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-05-13 18:51:28 +02:00
Tonghao Zhang
4c7f24f857 net: sysctl: introduce sysctl SYSCTL_THREE
This patch introdues the SYSCTL_THREE.

KUnit:
[00:10:14] ================ sysctl_test (10 subtests) =================
[00:10:14] [PASSED] sysctl_test_api_dointvec_null_tbl_data
[00:10:14] [PASSED] sysctl_test_api_dointvec_table_maxlen_unset
[00:10:14] [PASSED] sysctl_test_api_dointvec_table_len_is_zero
[00:10:14] [PASSED] sysctl_test_api_dointvec_table_read_but_position_set
[00:10:14] [PASSED] sysctl_test_dointvec_read_happy_single_positive
[00:10:14] [PASSED] sysctl_test_dointvec_read_happy_single_negative
[00:10:14] [PASSED] sysctl_test_dointvec_write_happy_single_positive
[00:10:14] [PASSED] sysctl_test_dointvec_write_happy_single_negative
[00:10:14] [PASSED] sysctl_test_api_dointvec_write_single_less_int_min
[00:10:14] [PASSED] sysctl_test_api_dointvec_write_single_greater_int_max
[00:10:14] =================== [PASSED] sysctl_test ===================

./run_kselftest.sh -c sysctl
...
ok 1 selftests: sysctl: sysctl.sh

Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: David Ahern <dsahern@kernel.org>
Cc: Simon Horman <horms@verge.net.au>
Cc: Julian Anastasov <ja@ssi.bg>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Jozsef Kadlecsik <kadlec@netfilter.org>
Cc: Florian Westphal <fw@strlen.de>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Lorenz Bauer <lmb@cloudflare.com>
Cc: Akhmat Karakotov <hmukos@yandex-team.ru>
Signed-off-by: Tonghao Zhang <xiangxia.m.yue@gmail.com>
Reviewed-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-05-03 10:15:06 +02:00
Jakub Kicinski
0e55546b18 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
include/linux/netdevice.h
net/core/dev.c
  6510ea973d ("net: Use this_cpu_inc() to increment net->core_stats")
  794c24e992 ("net-core: rx_otherhost_dropped to core_stats")
https://lore.kernel.org/all/20220428111903.5f4304e0@canb.auug.org.au/

drivers/net/wan/cosa.c
  d48fea8401 ("net: cosa: fix error check return value of register_chrdev()")
  89fbca3307 ("net: wan: remove support for COSA and SRP synchronous serial boards")
https://lore.kernel.org/all/20220428112130.1f689e5e@canb.auug.org.au/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-28 13:02:01 -07:00
Florian Westphal
743b83f15d netfilter: nft_socket: only do sk lookups when indev is available
Check if the incoming interface is available and NFT_BREAK
in case neither skb->sk nor input device are set.

Because nf_sk_lookup_slow*() assume packet headers are in the
'in' direction, use in postrouting is not going to yield a meaningful
result.  Same is true for the forward chain, so restrict the use
to prerouting, input and output.

Use in output work if a socket is already attached to the skb.

Fixes: 554ced0a6e ("netfilter: nf_tables: add support for native socket matching")
Reported-and-tested-by: Topi Miettinen <toiwoton@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-04-28 16:15:23 +02:00
Volodymyr Mytnyk
626873c446 netfilter: conntrack: fix udp offload timeout sysctl
`nf_flowtable_udp_timeout` sysctl option is available only
if CONFIG_NFT_FLOW_OFFLOAD enabled. But infra for this flow
offload UDP timeout was added under CONFIG_NF_FLOW_TABLE
config option. So, if you have CONFIG_NFT_FLOW_OFFLOAD
disabled and CONFIG_NF_FLOW_TABLE enabled, the
`nf_flowtable_udp_timeout` is not present in sysfs.
Please note, that TCP flow offload timeout sysctl option
is present even CONFIG_NFT_FLOW_OFFLOAD is disabled.

I suppose it was a typo in commit that adds UDP flow offload
timeout and CONFIG_NF_FLOW_TABLE should be used instead.

Fixes: 975c57504d ("netfilter: conntrack: Introduce udp offload timeout configuration")
Signed-off-by: Volodymyr Mytnyk <volodymyr.mytnyk@plvision.eu>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-04-27 15:48:49 +02:00
Florian Westphal
c7aab4f170 netfilter: nf_conntrack_tcp: re-init for syn packets only
Jaco Kroon reported tcp problems that Eric Dumazet and Neal Cardwell
pinpointed to nf_conntrack tcp_in_window() bug.

tcp trace shows following sequence:

I > R Flags [S], seq 3451342529, win 62580, options [.. tfo [|tcp]>
R > I Flags [S.], seq 2699962254, ack 3451342530, win 65535, options [..]
R > I Flags [P.], seq 1:89, ack 1, [..]

Note 3rd ACK is from responder to initiator so following branch is taken:
    } else if (((state->state == TCP_CONNTRACK_SYN_SENT
               && dir == IP_CT_DIR_ORIGINAL)
               || (state->state == TCP_CONNTRACK_SYN_RECV
               && dir == IP_CT_DIR_REPLY))
               && after(end, sender->td_end)) {

... because state == TCP_CONNTRACK_SYN_RECV and dir is REPLY.
This causes the scaling factor to be reset to 0: window scale option
is only present in syn(ack) packets.  This in turn makes nf_conntrack
mark valid packets as out-of-window.

This was always broken, it exists even in original commit where
window tracking was added to ip_conntrack (nf_conntrack predecessor)
in 2.6.9-rc1 kernel.

Restrict to 'tcph->syn', just like the 3rd condtional added in
commit 82b72cb946 ("netfilter: conntrack: re-init state for retransmitted syn-ack").

Upon closer look, those conditionals/branches can be merged:

Because earlier checks prevent syn-ack from showing up in
original direction, the 'dir' checks in the conditional quoted above are
redundant, remove them. Return early for pure syn retransmitted in reply
direction (simultaneous open).

Fixes: 9fb9cbb108 ("[NETFILTER]: Add nf_conntrack subsystem.")
Reported-by: Jaco Kroon <jaco@uls.co.za>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Jozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-04-27 15:48:45 +02:00
Pablo Neira Ayuso
babc3dc952 netfilter: nft_set_rbtree: overlap detection with element re-addition after deletion
This patch fixes spurious EEXIST errors.

Extend d2df92e98a ("netfilter: nft_set_rbtree: handle element
re-addition after deletion") to deal with elements with same end flags
in the same transation.

Reset the overlap flag as described by 7c84d41416 ("netfilter:
nft_set_rbtree: Detect partial overlaps on insertion").

Fixes: 7c84d41416 ("netfilter: nft_set_rbtree: Detect partial overlaps on insertion")
Fixes: d2df92e98a ("netfilter: nft_set_rbtree: handle element re-addition after deletion")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-04-22 15:49:15 +02:00
Pengcheng Yang
eba1a872cb ipvs: correctly print the memory size of ip_vs_conn_tab
The memory size of ip_vs_conn_tab changed after we use hlist
instead of list.

Fixes: 731109e784 ("ipvs: use hlist instead of list")
Signed-off-by: Pengcheng Yang <yangpc@wangsu.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-04-19 11:04:06 +02:00
Paolo Abeni
edf45f007a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-04-15 09:26:00 +02:00
Antoine Tenart
6c6f9f31ec netfilter: nf_tables: nft_parse_register can return a negative value
Since commit 6e1acfa387 ("netfilter: nf_tables: validate registers
coming from userspace.") nft_parse_register can return a negative value,
but the function prototype is still returning an unsigned int.

Fixes: 6e1acfa387 ("netfilter: nf_tables: validate registers coming from userspace.")
Signed-off-by: Antoine Tenart <atenart@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-04-12 11:36:37 +02:00
David S. Miller
4696ad36d7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next
Pablo Neira Ayuso says:

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

The following patchset contains Netfilter updates for net-next:

1) Replace unnecessary list_for_each_entry_continue() in nf_tables,
   from Jakob Koschel.

2) Add struct nf_conntrack_net_ecache to conntrack event cache and
   use it, from Florian Westphal.

3) Refactor ctnetlink_dump_list(), also from Florian.

4) Bump module reference counter on cttimeout object addition/removal,
   from Florian.

5) Consolidate nf_log MAC printer, from Phil Sutter.

6) Add basic logging support for unknown ethertype, from Phil Sutter.

7) Consolidate check for sysctl nf_log_all_netns toggle, also from Phil.

8) Replace hardcode value in nft_bitwise, from Jeremy Sowden.

9) Rename BASIC-like goto tags in nft_bitwise to more meaningful names,
   also from Jeremy.

10) nft_fib support for reverse path filtering with policy-based routing
    on iif. Extend selftests to cover for this new usecase, from Florian.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-11 11:47:58 +01:00
Florian Westphal
05ae2fba82 netfilter: nft_socket: make cgroup match work in input too
cgroupv2 helper function ignores the already-looked up sk
and uses skb->sk instead.

Just pass sk from the calling function instead; this will
make cgroup matching work for udp and tcp in input even when
edemux did not set skb->sk already.

Fixes: e0bb96db96 ("netfilter: nft_socket: add support for cgroupsv2")
Signed-off-by: Florian Westphal <fw@strlen.de>
Tested-by: Topi Miettinen <toiwoton@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-04-11 12:12:46 +02:00
Pablo Neira Ayuso
be8be04e5d netfilter: nft_fib: reverse path filter for policy-based routing on iif
If policy-based routing using the iif selector is used, then the fib
expression fails to look up for the reverse path from the prerouting
hook because the input interface cannot be inferred. In order to support
this scenario, extend the fib expression to allow to use after the route
lookup, from the forward hook.

This patch also adds support for the input hook for usability reasons.
Since the prerouting hook cannot be used for the scenario described
above, users need two rules: one for the forward chain and another rule
for the input chain to check for the reverse path check for locally
targeted traffic.

Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-04-11 12:10:09 +02:00
Jeremy Sowden
00bd435208 netfilter: bitwise: improve error goto labels
Replace two labels (`err1` and `err2`) with more informative ones.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
2022-04-09 12:02:23 +02:00