Commit Graph

1256 Commits

Author SHA1 Message Date
Pablo Neira Ayuso
c1592a8994 netfilter: nf_tables: deactivate anonymous set from preparation phase
Toggle deleted anonymous sets as inactive in the next generation, so
users cannot perform any update on it. Clear the generation bitmask
in case the transaction is aborted.

The following KASAN splat shows a set element deletion for a bound
anonymous set that has been already removed in the same transaction.

[   64.921510] ==================================================================
[   64.923123] BUG: KASAN: wild-memory-access in nf_tables_commit+0xa24/0x1490 [nf_tables]
[   64.924745] Write of size 8 at addr dead000000000122 by task test/890
[   64.927903] CPU: 3 PID: 890 Comm: test Not tainted 6.3.0+ #253
[   64.931120] Call Trace:
[   64.932699]  <TASK>
[   64.934292]  dump_stack_lvl+0x33/0x50
[   64.935908]  ? nf_tables_commit+0xa24/0x1490 [nf_tables]
[   64.937551]  kasan_report+0xda/0x120
[   64.939186]  ? nf_tables_commit+0xa24/0x1490 [nf_tables]
[   64.940814]  nf_tables_commit+0xa24/0x1490 [nf_tables]
[   64.942452]  ? __kasan_slab_alloc+0x2d/0x60
[   64.944070]  ? nf_tables_setelem_notify+0x190/0x190 [nf_tables]
[   64.945710]  ? kasan_set_track+0x21/0x30
[   64.947323]  nfnetlink_rcv_batch+0x709/0xd90 [nfnetlink]
[   64.948898]  ? nfnetlink_rcv_msg+0x480/0x480 [nfnetlink]

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-05-03 08:24:32 +02:00
Paolo Abeni
c248b27cfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-04-26 10:17:46 +02:00
Jakub Kicinski
ffcddcaed6 Merge tag 'nf-next-23-04-22' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next
Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

1) Reduce jumpstack footprint: Stash chain in last rule marker in blob for
   tracing. Remove last rule and chain from jumpstack. From Florian Westphal.

2) nf_tables validates all tables before committing the new rules.
   Unfortunately, this has two drawbacks:

   - Since addition of the transaction mutex pernet state gets written to
     outside of the locked section from the cleanup callback, this is
     wrong so do this cleanup directly after table has passed all checks.

   - Revalidate tables that saw no changes. This can be avoided by
     keeping the validation state per table, not per netns.

   From Florian Westphal.

3) Get rid of a few redundant pointers in the traceinfo structure.
   The three removed pointers are used in the expression evaluation loop,
   so gcc keeps them in registers. Passing them to the (inlined) helpers
   thus doesn't increase nft_do_chain text size, while stack is reduced
   by another 24 bytes on 64bit arches. From Florian Westphal.

4) IPVS cleanups in several ways without implementing any functional
   changes, aside from removing some debugging output:

   - Update width of source for ip_vs_sync_conn_options
     The operation is safe, use an annotation to describe it properly.

   - Consistently use array_size() in ip_vs_conn_init()
     It seems better to use helpers consistently.

   - Remove {Enter,Leave}Function. These seem to be well past their
     use-by date.

   - Correct spelling in comments.

   From Simon Horman.

5) Extended netlink error report for netdevice in flowtables and
   netdev/chains. Allow for incrementally add/delete devices to netdev
   basechain. Allow to create netdev chain without device.

* tag 'nf-next-23-04-22' of git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: nf_tables: allow to create netdev chain without device
  netfilter: nf_tables: support for deleting devices in an existing netdev chain
  netfilter: nf_tables: support for adding new devices to an existing netdev chain
  netfilter: nf_tables: rename function to destroy hook list
  netfilter: nf_tables: do not send complete notification of deletions
  netfilter: nf_tables: extended netlink error reporting for netdevice
  ipvs: Correct spelling in comments
  ipvs: Remove {Enter,Leave}Function
  ipvs: Consistently use array_size() in ip_vs_conn_init()
  ipvs: Update width of source for ip_vs_sync_conn_options
  netfilter: nf_tables: do not store rule in traceinfo structure
  netfilter: nf_tables: do not store verdict in traceinfo structure
  netfilter: nf_tables: do not store pktinfo in traceinfo structure
  netfilter: nf_tables: remove unneeded conditional
  netfilter: nf_tables: make validation state per table
  netfilter: nf_tables: don't write table validation state without mutex
  netfilter: nf_tables: don't store chain address on jump
  netfilter: nf_tables: don't store address of last rule on jump
  netfilter: nf_tables: merge nft_rules_old structure and end of ruleblob marker
====================

Link: https://lore.kernel.org/r/20230421235021.216950-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-24 15:37:36 -07:00
Jakub Kicinski
9a82cdc28f Merge tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2023-04-21

We've added 71 non-merge commits during the last 8 day(s) which contain
a total of 116 files changed, 13397 insertions(+), 8896 deletions(-).

The main changes are:

1) Add a new BPF netfilter program type and minimal support to hook
   BPF programs to netfilter hooks such as prerouting or forward,
   from Florian Westphal.

2) Fix race between btf_put and btf_idr walk which caused a deadlock,
   from Alexei Starovoitov.

3) Second big batch to migrate test_verifier unit tests into test_progs
   for ease of readability and debugging, from Eduard Zingerman.

4) Add support for refcounted local kptrs to the verifier for allowing
   shared ownership, useful for adding a node to both the BPF list and
   rbtree, from Dave Marchevsky.

5) Migrate bpf_for(), bpf_for_each() and bpf_repeat() macros from BPF
  selftests into libbpf-provided bpf_helpers.h header and improve
  kfunc handling, from Andrii Nakryiko.

6) Support 64-bit pointers to kfuncs needed for archs like s390x,
   from Ilya Leoshkevich.

7) Support BPF progs under getsockopt with a NULL optval,
   from Stanislav Fomichev.

8) Improve verifier u32 scalar equality checking in order to enable
   LLVM transformations which earlier had to be disabled specifically
   for BPF backend, from Yonghong Song.

9) Extend bpftool's struct_ops object loading to support links,
   from Kui-Feng Lee.

10) Add xsk selftest follow-up fixes for hugepage allocated umem,
    from Magnus Karlsson.

11) Support BPF redirects from tc BPF to ifb devices,
    from Daniel Borkmann.

12) Add BPF support for integer type when accessing variable length
    arrays, from Feng Zhou.

* tag 'for-netdev' of https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (71 commits)
  selftests/bpf: verifier/value_ptr_arith converted to inline assembly
  selftests/bpf: verifier/value_illegal_alu converted to inline assembly
  selftests/bpf: verifier/unpriv converted to inline assembly
  selftests/bpf: verifier/subreg converted to inline assembly
  selftests/bpf: verifier/spin_lock converted to inline assembly
  selftests/bpf: verifier/sock converted to inline assembly
  selftests/bpf: verifier/search_pruning converted to inline assembly
  selftests/bpf: verifier/runtime_jit converted to inline assembly
  selftests/bpf: verifier/regalloc converted to inline assembly
  selftests/bpf: verifier/ref_tracking converted to inline assembly
  selftests/bpf: verifier/map_ptr_mixing converted to inline assembly
  selftests/bpf: verifier/map_in_map converted to inline assembly
  selftests/bpf: verifier/lwt converted to inline assembly
  selftests/bpf: verifier/loops1 converted to inline assembly
  selftests/bpf: verifier/jeq_infer_not_null converted to inline assembly
  selftests/bpf: verifier/direct_packet_access converted to inline assembly
  selftests/bpf: verifier/d_path converted to inline assembly
  selftests/bpf: verifier/ctx converted to inline assembly
  selftests/bpf: verifier/btf_ctx_access converted to inline assembly
  selftests/bpf: verifier/bpf_get_stack converted to inline assembly
  ...
====================

Link: https://lore.kernel.org/r/20230421211035.9111-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-21 20:32:37 -07:00
Pablo Neira Ayuso
b9703ed44f netfilter: nf_tables: support for adding new devices to an existing netdev chain
This patch allows users to add devices to an existing netdev chain.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-22 01:39:42 +02:00
Florian Westphal
46df417544 netfilter: nf_tables: do not store rule in traceinfo structure
pass it as argument instead.  This reduces size of traceinfo to
16 bytes.  Total stack usage:

 nf_tables_core.c:252 nft_do_chain    304     static

While its possible to also pass basechain as argument, doing so
increases nft_do_chaininfo function size.

Unlike pktinfo/verdict/rule the basechain info isn't used in
the expression evaluation path. gcc places it on the stack, which
results in extra push/pop when it gets passed to the trace helpers
as argument rather than as part of the traceinfo structure.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-22 01:39:41 +02:00
Florian Westphal
0a202145d5 netfilter: nf_tables: do not store verdict in traceinfo structure
Just pass it as argument to nft_trace_notify. Stack is reduced by 8 bytes:

nf_tables_core.c:256 nft_do_chain    312     static

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-22 01:39:41 +02:00
Florian Westphal
698bb828a6 netfilter: nf_tables: do not store pktinfo in traceinfo structure
pass it as argument.  No change in object size.

stack usage decreases by 8 byte:
 nf_tables_core.c:254  nft_do_chain       320     static

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-22 01:39:41 +02:00
Florian Westphal
00c320f9b7 netfilter: nf_tables: make validation state per table
We only need to validate tables that saw changes in the current
transaction.

The existing code revalidates all tables, but this isn't needed as
cross-table jumps are not allowed (chains have table scope).

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-22 01:39:40 +02:00
Florian Westphal
63e9bbbcca netfilter: nf_tables: don't store chain address on jump
Now that the rule trailer/end marker and the rcu head reside in the
same structure, we no longer need to save/restore the chain pointer
when performing/returning from a jump.

We can simply let the trace infra walk the evaluated rule until it
hits the end marker and then fetch the chain pointer from there.

When the rule is NULL (policy tracing), then chain and basechain
pointers were already identical, so just use the basechain.

This cuts size of jumpstack in half, from 256 to 128 bytes in 64bit,
scripts/stackusage says:

nf_tables_core.c:251 nft_do_chain    328     static

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-22 01:39:40 +02:00
Florian Westphal
fd9c663b9a bpf: minimal support for programs hooked into netfilter framework
This adds minimal support for BPF_PROG_TYPE_NETFILTER bpf programs
that will be invoked via the NF_HOOK() points in the ip stack.

Invocation incurs an indirect call.  This is not a necessity: Its
possible to add 'DEFINE_BPF_DISPATCHER(nf_progs)' and handle the
program invocation with the same method already done for xdp progs.

This isn't done here to keep the size of this chunk down.

Verifier restricts verdicts to either DROP or ACCEPT.

Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20230421170300.24115-3-fw@strlen.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 11:34:14 -07:00
Florian Westphal
84601d6ee6 bpf: add bpf_link support for BPF_NETFILTER programs
Add bpf_link support skeleton.  To keep this reviewable, no bpf program
can be invoked yet, if a program is attached only a c-stub is called and
not the actual bpf program.

Defaults to 'y' if both netfilter and bpf syscall are enabled in kconfig.

Uapi example usage:
	union bpf_attr attr = { };

	attr.link_create.prog_fd = progfd;
	attr.link_create.attach_type = 0; /* unused */
	attr.link_create.netfilter.pf = PF_INET;
	attr.link_create.netfilter.hooknum = NF_INET_LOCAL_IN;
	attr.link_create.netfilter.priority = -128;

	err = bpf(BPF_LINK_CREATE, &attr, sizeof(attr));

... this would attach progfd to ipv4:input hook.

Such hook gets removed automatically if the calling program exits.

BPF_NETFILTER program invocation is added in followup change.

NF_HOOK_OP_BPF enum will eventually be read from nfnetlink_hook, it
allows to tell userspace which program is attached at the given hook
when user runs 'nft hook list' command rather than just the priority
and not-very-helpful 'this hook runs a bpf prog but I can't tell which
one'.

Will also be used to disallow registration of two bpf programs with
same priority in a followup patch.

v4: arm32 cmpxchg only supports 32bit operand
    s/prio/priority/
v3: restrict prog attachment to ip/ip6 for now, lets lift restrictions if
    more use cases pop up (arptables, ebtables, netdev ingress/egress etc).

Signed-off-by: Florian Westphal <fw@strlen.de>
Link: https://lore.kernel.org/r/20230421170300.24115-2-fw@strlen.de
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-04-21 11:34:14 -07:00
Jakub Kicinski
681c5b51dc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Adjacent changes:

net/mptcp/protocol.h
  63740448a3 ("mptcp: fix accept vs worker race")
  2a6a870e44 ("mptcp: stops worker on unaccepted sockets at listener close")
  ddb1a072f8 ("mptcp: move first subflow allocation at mpc access time")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-20 16:29:51 -07:00
Tzung-Bi Shih
73db1b8f2b netfilter: conntrack: fix wrong ct->timeout value
(struct nf_conn)->timeout is an interval before the conntrack
confirmed.  After confirmed, it becomes a timestamp.

It is observed that timeout of an unconfirmed conntrack:
- Set by calling ctnetlink_change_timeout(). As a result,
  `nfct_time_stamp` was wrongly added to `ct->timeout` twice.
- Get by calling ctnetlink_dump_timeout(). As a result,
  `nfct_time_stamp` was wrongly subtracted.

Call Trace:
 <TASK>
 dump_stack_lvl
 ctnetlink_dump_timeout
 __ctnetlink_glue_build
 ctnetlink_glue_build
 __nfqnl_enqueue_packet
 nf_queue
 nf_hook_slow
 ip_mc_output
 ? __pfx_ip_finish_output
 ip_send_skb
 ? __pfx_dst_output
 udp_send_skb
 udp_sendmsg
 ? __pfx_ip_generic_getfrag
 sock_sendmsg

Separate the 2 cases in:
- Setting `ct->timeout` in __nf_ct_set_timeout().
- Getting `ct->timeout` in ctnetlink_dump_timeout().

Pablo appends:

Update ctnetlink to set up the timeout _after_ the IPS_CONFIRMED flag is
set on, otherwise conntrack creation via ctnetlink breaks.

Note that the problem described in this patch occurs since the
introduction of the nfnetlink_queue conntrack support, select a
sufficiently old Fixes: tag for -stable kernel to pick up this fix.

Fixes: a4b4766c3c ("netfilter: nfnetlink_queue: rename related to nfqueue attaching conntrack info")
Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-19 12:08:38 +02:00
Pablo Neira Ayuso
d46fc89414 netfilter: nf_tables: validate catch-all set elements
catch-all set element might jump/goto to chain that uses expressions
that require validation.

Fixes: aaa31047a6 ("netfilter: nftables: add catch-all set element support")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-04-18 09:12:22 +02:00
Jeremy Sowden
6f56ad1b92 netfilter: nft_redir: use struct nf_nat_range2 throughout and deduplicate eval call-backs
`nf_nat_redirect_ipv4` takes a `struct nf_nat_ipv4_multi_range_compat`,
but converts it internally to a `struct nf_nat_range2`.  Change the
function to take the latter, factor out the code now shared with
`nf_nat_redirect_ipv6`, move the conversion to the xt_REDIRECT module,
and update the ipv4 range initialization in the nft_redir module.

Replace a bare hex constant for 127.0.0.1 with a macro.

Remove `WARN_ON`.  `nf_nat_setup_info` calls `nf_ct_is_confirmed`:

	/* Can't setup nat info for confirmed ct. */
	if (nf_ct_is_confirmed(ct))
		return NF_ACCEPT;

This means that `ct` cannot be null or the kernel will crash, and
implies that `ctinfo` is `IP_CT_NEW` or `IP_CT_RELATED`.

nft_redir has separate ipv4 and ipv6 call-backs which share much of
their code, and an inet one switch containing a switch that calls one of
the others based on the family of the packet.  Merge the ipv4 and ipv6
ones into the inet one in order to get rid of the duplicate code.

Const-qualify the `priv` pointer since we don't need to write through
it.

Assign `priv->flags` to the range instead of OR-ing it in.

Set the `NF_NAT_RANGE_PROTO_SPECIFIED` flag once during init, rather
than on every eval.

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
2023-03-22 21:48:59 +01:00
Florian Westphal
4a02426787 netfilter: tproxy: fix deadlock due to missing BH disable
The xtables packet traverser performs an unconditional local_bh_disable(),
but the nf_tables evaluation loop does not.

Functions that are called from either xtables or nftables must assume
that they can be called in process context.

inet_twsk_deschedule_put() assumes that no softirq interrupt can occur.
If tproxy is used from nf_tables its possible that we'll deadlock
trying to aquire a lock already held in process context.

Add a small helper that takes care of this and use it.

Link: https://lore.kernel.org/netfilter-devel/401bd6ed-314a-a196-1cdc-e13c720cc8f2@balasys.hu/
Fixes: 4ed8eb6570 ("netfilter: nf_tables: Add native tproxy support")
Reported-and-tested-by: Major Dávid <major.david@balasys.hu>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-03-06 12:09:48 +01:00
David S. Miller
1155a2281d Merge git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next
Pablo Neira Ayuso says:

====================
Netfilter/IPVS updates for net-next

The following patchset contains Netfilter updates for net-next:

1) Add safeguard to check for NULL tupe in objects updates via
   NFT_MSG_NEWOBJ, this should not ever happen. From Alok Tiwari.

2) Incorrect pointer check in the new destroy rule command,
   from Yang Yingliang.

3) Incorrect status bitcheck in nf_conntrack_udp_packet(),
   from Florian Westphal.

4) Simplify seq_print_acct(), from Ilia Gavrilov.

5) Use 2-arg optimal variant of kfree_rcu() in IPVS,
   from Julian Anastasov.

6) TCP connection enters CLOSE state in conntrack for locally
   originated TCP reset packet from the reject target,
   from Florian Westphal.

The fixes #2 and #3 in this series address issues from the previous pull
nf-next request in this net-next cycle.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2023-02-20 10:53:56 +00:00
Florian Westphal
2954fe60e3 netfilter: let reset rules clean out conntrack entries
iptables/nftables support responding to tcp packets with tcp resets.

The generated tcp reset packet passes through both output and postrouting
netfilter hooks, but conntrack will never see them because the generated
skb has its ->nfct pointer copied over from the packet that triggered the
reset rule.

If the reset rule is used for established connections, this
may result in the conntrack entry to be around for a very long
time (default timeout is 5 days).

One way to avoid this would be to not copy the nf_conn pointer
so that the rest packet passes through conntrack too.

Problem is that output rules might not have the same conntrack
zone setup as the prerouting ones, so its possible that the
reset skb won't find the correct entry.  Generating a template
entry for the skb seems error prone as well.

Add an explicit "closing" function that switches a confirmed
conntrack entry to closed state and wire this up for tcp.

If the entry isn't confirmed, no action is needed because
the conntrack entry will never be committed to the table.

Reported-by: Russel King <linux@armlinux.org.uk>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-02-17 13:04:56 +01:00
Xin Long
0785407e78 net: extract nf_ct_handle_fragments to nf_conntrack_ovs
Now handle_fragments() in OVS and TC have the similar code, and
this patch removes the duplicate code by moving the function
to nf_conntrack_ovs.

Note that skb_clear_hash(skb) or skb->ignore_df = 1 should be
done only when defrag returns 0, as it does in other places
in kernel.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-10 16:23:03 -08:00
Xin Long
67fc5d7ffb net: extract nf_ct_skb_network_trim function to nf_conntrack_ovs
There are almost the same code in ovs_skb_network_trim() and
tcf_ct_skb_network_trim(), this patch extracts them into a function
nf_ct_skb_network_trim() and moves the function to nf_conntrack_ovs.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Aaron Conole <aconole@redhat.com>
Acked-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-10 16:23:03 -08:00
Vlad Buslov
1a441a9b8b netfilter: flowtable: cache info of last offload
Modify flow table offload to cache the last ct info status that was passed
to the driver offload callbacks by extending enum nf_flow_flags with new
"NF_FLOW_HW_ESTABLISHED" flag. Set the flag if ctinfo was 'established'
during last act_ct meta actions fill call. This infrastructure change is
necessary to optimize promoting of UDP connections from 'new' to
'established' in following patches in this series.

Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-02-03 09:31:24 +00:00
Vlad Buslov
8f84780b84 netfilter: flowtable: allow unidirectional rules
Modify flow table offload to support unidirectional connections by
extending enum nf_flow_flags with new "NF_FLOW_HW_BIDIRECTIONAL" flag. Only
offload reply direction when the flag is set. This infrastructure change is
necessary to support offloading UDP NEW connections in original direction
in following patches in series.

Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-02-03 09:31:24 +00:00
Xin Long
a13fbf5ed5 netfilter: use skb_ip_totlen and iph_totlen
There are also quite some places in netfilter that may process IPv4 TCP
GSO packets, we need to replace them too.

In length_mt(), we have to use u_int32_t/int to accept skb_ip_totlen()
return value, otherwise it may overflow and mismatch. This change will
also help us add selftest for IPv4 BIG TCP in the following patch.

Note that we don't need to replace the one in tcpmss_tg4(), as it will
return if there is data after tcphdr in tcpmss_mangle_packet(). The
same in mangle_contents() in nf_nat_helper.c, it returns false when
skb->len + extra > 65535 in enlarge_skb().

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-01 20:54:27 -08:00
Florian Westphal
d9e7891476 netfilter: nf_tables: avoid retpoline overhead for some ct expression calls
nft_ct expression cannot be made builtin to nf_tables without also
forcing the conntrack itself to be builtin.

However, this can be avoided by splitting retrieval of a few
selector keys that only need to access the nf_conn structure,
i.e. no function calls to nf_conntrack code.

Many rulesets start with something like
"ct status established,related accept"

With this change, this no longer requires an indirect call, which
gives about 1.8% more throughput with a simple conntrack-enabled
forwarding test (retpoline thunk used).

Signed-off-by: Florian Westphal <fw@strlen.de>
2023-01-18 13:05:25 +01:00