Commit Graph

693 Commits

Author SHA1 Message Date
Eric Dumazet
d677aebd66 tcp: move sysctl_tcp_l3mdev_accept to netns_ipv4_read_rx
sysctl_tcp_l3mdev_accept is read from TCP receive fast path from
tcp_v6_early_demux(),
 __inet6_lookup_established,
  inet_request_bound_dev_if().

Move it to netns_ipv4_read_rx.

Remove the '#ifdef CONFIG_NET_L3_MASTER_DEV' that was guarding
its definition.

Note this adds a hole of three bytes that could be filled later.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Cc: Wei Wang <weiwan@google.com>
Cc: Coco Li <lixiaoyan@google.com>
Link: https://patch.msgid.link/20241010034100.320832-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-11 08:45:24 -07:00
Kuniyuki Iwashima
1675f38521 ipv4: Namespacify IPv4 address GC.
Each IPv4 address could have a lifetime, which is useful for DHCP,
and GC is periodically executed as check_lifetime_work.

check_lifetime() does the actual GC under RTNL.

  1. Acquire RTNL
  2. Iterate inet_addr_lst
  3. Remove IPv4 address if expired
  4. Release RTNL

Namespacifying the GC is required for per-netns RTNL, but using the
per-netns hash table will shorten the time on the hash bucket iteration
under RTNL.

Let's add per-netns GC work and use the per-netns hash table.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20241008172906.1326-4-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-09 20:08:08 -07:00
Kuniyuki Iwashima
87173021f1 ipv4: Link IPv4 address to per-netns hash table.
As a prep for per-netns RTNL conversion, we want to namespacify
the IPv4 address hash table and the GC work.

Let's allocate the per-netns IPv4 address hash table to
net->ipv4.inet_addr_lst and link IPv4 addresses into it.

The actual users will be converted later.

Note that the IPv6 address hash table is already namespacified.

Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20241008172906.1326-2-kuniyu@amazon.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-09 20:08:07 -07:00
Jason Xing
da5e06dee5 net-timestamp: namespacify the sysctl_tstamp_allow_data
Let it be tuned in per netns by admins.

Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20241005222609.94980-1-kerneljasonxing@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-08 15:33:11 -07:00
Florian Westphal
645546a05b xfrm: policy: remove last remnants of pernet inexact list
xfrm_net still contained the no-longer-used inexact policy list heads,
remove them.

Fixes: a54ad727f7 ("xfrm: policy: remove remaining use of inexact list")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2024-09-24 09:58:16 +02:00
Eric Dumazet
f17bf505ff icmp: icmp_msgs_per_sec and icmp_msgs_burst sysctls become per netns
Previous patch made ICMP rate limits per netns, it makes sense
to allow each netns to change the associated sysctl.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20240829144641.3880376-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-30 11:14:06 -07:00
Eric Dumazet
b056b4cd91 icmp: move icmp_global.credit and icmp_global.stamp to per netns storage
Host wide ICMP ratelimiter should be per netns, to provide better isolation.

Following patch in this series makes the sysctl per netns.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20240829144641.3880376-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-30 11:14:06 -07:00
Simon Horman
70d0bb45fa net: Correct spelling in headers
Correct spelling in Networking headers.
As reported by codespell.

Signed-off-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20240822-net-spell-v1-12-3a98971ce2d2@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-26 09:37:23 -07:00
Jakub Kicinski
62fdd1708f ipsec-next-2024-07-13
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Merge tag 'ipsec-next-2024-07-13' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next

Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2024-07-13

1) Support sending NAT keepalives in ESP in UDP states.
   Userspace IKE daemon had to do this before, but the
   kernel can better keep track of it.
   From Eyal Birger.

2) Support IPsec crypto offload for IPv6 ESP and IPv4 UDP-encapsulated
   ESP data paths. Currently, IPsec crypto offload is enabled for GRO
   code path only. This patchset support UDP encapsulation for the non
   GRO path. From Mike Yu.

* tag 'ipsec-next-2024-07-13' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next:
  xfrm: Support crypto offload for outbound IPv4 UDP-encapsulated ESP packet
  xfrm: Support crypto offload for inbound IPv4 UDP-encapsulated ESP packet
  xfrm: Allow UDP encapsulation in crypto offload control path
  xfrm: Support crypto offload for inbound IPv6 ESP packets not in GRO path
  xfrm: support sending NAT keepalives in ESP in UDP states
====================

Link: https://patch.msgid.link/20240713102416.3272997-1-steffen.klassert@secunet.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-14 07:56:32 -07:00
Eyal Birger
f531d13bdf xfrm: support sending NAT keepalives in ESP in UDP states
Add the ability to send out RFC-3948 NAT keepalives from the xfrm stack.

To use, Userspace sets an XFRM_NAT_KEEPALIVE_INTERVAL integer property when
creating XFRM outbound states which denotes the number of seconds between
keepalive messages.

Keepalive messages are sent from a per net delayed work which iterates over
the xfrm states. The logic is guarded by the xfrm state spinlock due to the
xfrm state walk iterator.

Possible future enhancements:

- Adding counters to keep track of sent keepalives.
- deduplicate NAT keepalives between states sharing the same nat keepalive
  parameters.
- provisioning hardware offloads for devices capable of implementing this.
- revise xfrm state list to use an rcu list in order to avoid running this
  under spinlock.

Suggested-by: Paul Wouters <paul.wouters@aiven.io>
Tested-by: Paul Wouters <paul.wouters@aiven.io>
Tested-by: Antony Antony <antony.antony@secunet.com>
Signed-off-by: Eyal Birger <eyal.birger@gmail.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2024-06-26 13:22:42 +02:00
Jakub Kicinski
a6ec08beec Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

drivers/net/ethernet/broadcom/bnxt/bnxt.c
  1e7962114c ("bnxt_en: Restore PTP tx_avail count in case of skb_pad() error")
  165f87691a ("bnxt_en: add timestamping statistics support")

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-20 13:49:59 -07:00
Jianguo Wu
a2225e0250 netfilter: move the sysctl nf_hooks_lwtunnel into the netfilter core
Currently, the sysctl net.netfilter.nf_hooks_lwtunnel depends on the
nf_conntrack module, but the nf_conntrack module is not always loaded.
Therefore, accessing net.netfilter.nf_hooks_lwtunnel may have an error.

Move sysctl nf_hooks_lwtunnel into the netfilter core.

Fixes: 7a3f5b0de3 ("netfilter: add netfilter hooks to SRv6 data plane")
Suggested-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Jianguo Wu <wujianguo@chinatelecom.cn>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2024-06-19 18:41:59 +02:00
Petr Machata
4ee2a8cace net: ipv4: Add a sysctl to set multipath hash seed
When calculating hashes for the purpose of multipath forwarding, both IPv4
and IPv6 code currently fall back on flow_hash_from_keys(). That uses a
randomly-generated seed. That's a fine choice by default, but unfortunately
some deployments may need a tighter control over the seed used.

In this patch, make the seed configurable by adding a new sysctl key,
net.ipv4.fib_multipath_hash_seed to control the seed. This seed is used
specifically for multipath forwarding and not for the other concerns that
flow_hash_from_keys() is used for, such as queue selection. Expose the knob
as sysctl because other such settings, such as headers to hash, are also
handled that way. Like those, the multipath hash seed is a per-netns
variable.

Despite being placed in the net.ipv4 namespace, the multipath seed sysctl
is used for both IPv4 and IPv6, similarly to e.g. a number of TCP
variables.

The seed used by flow_hash_from_keys() is a 128-bit quantity. However it
seems that usually the seed is a much more modest value. 32 bits seem
typical (Cisco, Cumulus), some systems go even lower. For that reason, and
to decouple the user interface from implementation details, go with a
32-bit quantity, which is then quadruplicated to form the siphash key.

Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240607151357.421181-3-petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-12 16:42:11 -07:00
Kevin Yang
f086edef71 tcp: add sysctl_tcp_rto_min_us
Adding a sysctl knob to allow user to specify a default
rto_min at socket init time, other than using the hard
coded 200ms default rto_min.

Note that the rto_min route option has the highest precedence
for configuring this setting, followed by the TCP_BPF_RTO_MIN
socket option, followed by the tcp_rto_min_us sysctl.

Signed-off-by: Kevin Yang <yyd@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Yuchung Cheng <ycheng@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-06-05 13:42:54 +01:00
Eric Dumazet
f5769faeec net: Namespace-ify sysctl_optmem_max
optmem_max being used in tx zerocopy,
we want to be able to control it on a netns basis.

Following patch changes two tests.

Tested:

oqq130:~# cat /proc/sys/net/core/optmem_max
131072
oqq130:~# echo 1000000 >/proc/sys/net/core/optmem_max
oqq130:~# cat /proc/sys/net/core/optmem_max
1000000
oqq130:~# unshare -n
oqq130:~# cat /proc/sys/net/core/optmem_max
131072
oqq130:~# exit
logout
oqq130:~# cat /proc/sys/net/core/optmem_max
1000000

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-12-15 11:01:27 +00:00
David Laight
d9f28735af Use READ/WRITE_ONCE() for IP local_port_range.
Commit 227b60f510 added a seqlock to ensure that the low and high
port numbers were always updated together.
This is overkill because the two 16bit port numbers can be held in
a u32 and read/written in a single instruction.

More recently 91d0b78c51 added support for finer per-socket limits.
The user-supplied value is 'high << 16 | low' but they are held
separately and the socket options protected by the socket lock.

Use a u32 containing 'high << 16 | low' for both the 'net' and 'sk'
fields and use READ_ONCE()/WRITE_ONCE() to ensure both values are
always updated together.

Change (the now trival) inet_get_local_port_range() to a static inline
to optimise the calling code.
(In particular avoiding returning integers by reference.)

Signed-off-by: David Laight <david.laight@aculab.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Acked-by: Mat Martineau <martineau@kernel.org>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/4e505d4198e946a8be03fb1b4c3072b0@AcuMS.aculab.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-12-08 10:44:42 -08:00
Coco Li
18fd64d254 netns-ipv4: reorganize netns_ipv4 fast path variables
Reorganize fast path variables on tx-txrx-rx order.
Fastpath cacheline ends after sysctl_tcp_rmem.
There are only read-only variables here. (write is on the control path
and not considered in this case)

Below data generated with pahole on x86 architecture.
Fast path variables span cache lines before change: 4
Fast path variables span cache lines after change: 2

Suggested-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Wei Wang <weiwan@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Coco Li <lixiaoyan@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-12-02 22:24:36 +00:00
Guangguan Wang
1f2c9dd73f net/smc: add sysctl for max conns per lgr for SMC-R v2.1
Add a new sysctl: net.smc.smcr_max_conns_per_lgr, which is
used to control the preferred max connections per lgr for
SMC-R v2.1. The default value of this sysctl is 255, and
the acceptable value ranges from 16 to 255.

Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-11-24 12:13:14 +00:00
Guangguan Wang
f8e80fc4ac net/smc: add sysctl for max links per lgr for SMC-R v2.1
Add a new sysctl: net.smc.smcr_max_links_per_lgr, which is
used to control the preferred max links per lgr for SMC-R
v2.1. The default value of this sysctl is 2, and the acceptable
value ranges from 1 to 2.

Signed-off-by: Guangguan Wang <guangguan.wang@linux.alibaba.com>
Reviewed-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-11-24 12:13:14 +00:00
Florian Westphal
643d126036 netfilter: conntrack: switch connlabels to atomic_t
The spinlock is back from the day when connabels did not have
a fixed size and reallocation had to be supported.

Remove it.  This change also allows to call the helpers from
softirq or timers without deadlocks.

Also add WARN()s to catch refcounting imbalances.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-10-24 13:16:30 +02:00
Jakub Kicinski
041c3466f3 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

net/mac80211/key.c
  02e0e426a2 ("wifi: mac80211: fix error path key leak")
  2a8b665e6b ("wifi: mac80211: remove key_mtx")
  7d6904bf26 ("Merge wireless into wireless-next")
https://lore.kernel.org/all/20231012113648.46eea5ec@canb.auug.org.au/

Adjacent changes:

drivers/net/ethernet/ti/Kconfig
  a602ee3176 ("net: ethernet: ti: Fix mixed module-builtin object")
  98bdeae950 ("net: cpmac: remove driver to prepare for platform removal")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-19 13:29:01 -07:00
Haiyang Zhang
562b1fdf06 tcp: Set pingpong threshold via sysctl
TCP pingpong threshold is 1 by default. But some applications, like SQL DB
may prefer a higher pingpong threshold to activate delayed acks in quick
ack mode for better performance.

The pingpong threshold and related code were changed to 3 in the year
2019 in:
  commit 4a41f453be ("tcp: change pingpong threshold to 3")
And reverted to 1 in the year 2022 in:
  commit 4d8f24eeed ("Revert "tcp: change pingpong threshold to 3"")

There is no single value that fits all applications.
Add net.ipv4.tcp_pingpong_thresh sysctl tunable, so it can be tuned for
optimal performance based on the application needs.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/1697056244-21888-1-git-send-email-haiyangz@microsoft.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-10-16 14:55:32 -07:00
Eric Dumazet
3e4bc23926 xfrm: fix a data-race in xfrm_gen_index()
xfrm_gen_index() mutual exclusion uses net->xfrm.xfrm_policy_lock.

This means we must use a per-netns idx_generator variable,
instead of a static one.
Alternative would be to use an atomic variable.

syzbot reported:

BUG: KCSAN: data-race in xfrm_sk_policy_insert / xfrm_sk_policy_insert

write to 0xffffffff87005938 of 4 bytes by task 29466 on cpu 0:
xfrm_gen_index net/xfrm/xfrm_policy.c:1385 [inline]
xfrm_sk_policy_insert+0x262/0x640 net/xfrm/xfrm_policy.c:2347
xfrm_user_policy+0x413/0x540 net/xfrm/xfrm_state.c:2639
do_ipv6_setsockopt+0x1317/0x2ce0 net/ipv6/ipv6_sockglue.c:943
ipv6_setsockopt+0x57/0x130 net/ipv6/ipv6_sockglue.c:1012
rawv6_setsockopt+0x21e/0x410 net/ipv6/raw.c:1054
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3697
__sys_setsockopt+0x1c9/0x230 net/socket.c:2263
__do_sys_setsockopt net/socket.c:2274 [inline]
__se_sys_setsockopt net/socket.c:2271 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2271
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffffffff87005938 of 4 bytes by task 29460 on cpu 1:
xfrm_sk_policy_insert+0x13e/0x640
xfrm_user_policy+0x413/0x540 net/xfrm/xfrm_state.c:2639
do_ipv6_setsockopt+0x1317/0x2ce0 net/ipv6/ipv6_sockglue.c:943
ipv6_setsockopt+0x57/0x130 net/ipv6/ipv6_sockglue.c:1012
rawv6_setsockopt+0x21e/0x410 net/ipv6/raw.c:1054
sock_common_setsockopt+0x61/0x70 net/core/sock.c:3697
__sys_setsockopt+0x1c9/0x230 net/socket.c:2263
__do_sys_setsockopt net/socket.c:2274 [inline]
__se_sys_setsockopt net/socket.c:2271 [inline]
__x64_sys_setsockopt+0x66/0x80 net/socket.c:2271
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00006ad8 -> 0x00006b18

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 29460 Comm: syz-executor.1 Not tainted 6.5.0-rc5-syzkaller-00243-g9106536c1aa3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023

Fixes: 1121994c80 ("netns xfrm: policy insertion in netns")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2023-09-13 09:20:28 +02:00
Eric Dumazet
133c4c0d37 tcp: defer regular ACK while processing socket backlog
This idea came after a particular workload requested
the quickack attribute set on routes, and a performance
drop was noticed for large bulk transfers.

For high throughput flows, it is best to use one cpu
running the user thread issuing socket system calls,
and a separate cpu to process incoming packets from BH context.
(With TSO/GRO, bottleneck is usually the 'user' cpu)

Problem is the user thread can spend a lot of time while holding
the socket lock, forcing BH handler to queue most of incoming
packets in the socket backlog.

Whenever the user thread releases the socket lock, it must first
process all accumulated packets in the backlog, potentially
adding latency spikes. Due to flood mitigation, having too many
packets in the backlog increases chance of unexpected drops.

Backlog processing unfortunately shifts a fair amount of cpu cycles
from the BH cpu to the 'user' cpu, thus reducing max throughput.

This patch takes advantage of the backlog processing,
and the fact that ACK are mostly cumulative.

The idea is to detect we are in the backlog processing
and defer all eligible ACK into a single one,
sent from tcp_release_cb().

This saves cpu cycles on both sides, and network resources.

Performance of a single TCP flow on a 200Gbit NIC:

- Throughput is increased by 20% (100Gbit -> 120Gbit).
- Number of generated ACK per second shrinks from 240,000 to 40,000.
- Number of backlog drops per second shrinks from 230 to 0.

Benchmark context:
 - Regular netperf TCP_STREAM (no zerocopy)
 - Intel(R) Xeon(R) Platinum 8481C (Saphire Rapids)
 - MAX_SKB_FRAGS = 17 (~60KB per GRO packet)

This feature is guarded by a new sysctl, and enabled by default:
 /proc/sys/net/ipv4/tcp_backlog_ack_defer

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Dave Taht <dave.taht@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-12 19:10:01 +02:00
Jörn-Thorben Hinz
f614a29d6c net: Remove leftover include from nftables.h
Commit db3685b404 ("net: remove obsolete members from struct net")
removed the uses of struct list_head from this header, without removing
the corresponding included header.

Signed-off-by: Jörn-Thorben Hinz <jthinz@mailbox.tu-berlin.de>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-08-13 14:55:25 +01:00
Eric Dumazet
dfa2f04833 tcp: get rid of sysctl_tcp_adv_win_scale
With modern NIC drivers shifting to full page allocations per
received frame, we face the following issue:

TCP has one per-netns sysctl used to tweak how to translate
a memory use into an expected payload (RWIN), in RX path.

tcp_win_from_space() implementation is limited to few cases.

For hosts dealing with various MSS, we either under estimate
or over estimate the RWIN we send to the remote peers.

For instance with the default sysctl_tcp_adv_win_scale value,
we expect to store 50% of payload per allocated chunk of memory.

For the typical use of MTU=1500 traffic, and order-0 pages allocations
by NIC drivers, we are sending too big RWIN, leading to potential
tcp collapse operations, which are extremely expensive and source
of latency spikes.

This patch makes sysctl_tcp_adv_win_scale obsolete, and instead
uses a per socket scaling factor, so that we can precisely
adjust the RWIN based on effective skb->len/skb->truesize ratio.

This patch alone can double TCP receive performance when receivers
are too slow to drain their receive queue, or by allowing
a bigger RWIN when MSS is close to PAGE_SIZE.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Link: https://lore.kernel.org/r/20230717152917.751987-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-07-18 18:41:18 -07:00
mfreemon@cloudflare.com
b650d953cd tcp: enforce receive buffer memory limits by allowing the tcp window to shrink
Under certain circumstances, the tcp receive buffer memory limit
set by autotuning (sk_rcvbuf) is increased due to incoming data
packets as a result of the window not closing when it should be.
This can result in the receive buffer growing all the way up to
tcp_rmem[2], even for tcp sessions with a low BDP.

To reproduce:  Connect a TCP session with the receiver doing
nothing and the sender sending small packets (an infinite loop
of socket send() with 4 bytes of payload with a sleep of 1 ms
in between each send()).  This will cause the tcp receive buffer
to grow all the way up to tcp_rmem[2].

As a result, a host can have individual tcp sessions with receive
buffers of size tcp_rmem[2], and the host itself can reach tcp_mem
limits, causing the host to go into tcp memory pressure mode.

The fundamental issue is the relationship between the granularity
of the window scaling factor and the number of byte ACKed back
to the sender.  This problem has previously been identified in
RFC 7323, appendix F [1].

The Linux kernel currently adheres to never shrinking the window.

In addition to the overallocation of memory mentioned above, the
current behavior is functionally incorrect, because once tcp_rmem[2]
is reached when no remediations remain (i.e. tcp collapse fails to
free up any more memory and there are no packets to prune from the
out-of-order queue), the receiver will drop in-window packets
resulting in retransmissions and an eventual timeout of the tcp
session.  A receive buffer full condition should instead result
in a zero window and an indefinite wait.

In practice, this problem is largely hidden for most flows.  It
is not applicable to mice flows.  Elephant flows can send data
fast enough to "overrun" the sk_rcvbuf limit (in a single ACK),
triggering a zero window.

But this problem does show up for other types of flows.  Examples
are websockets and other type of flows that send small amounts of
data spaced apart slightly in time.  In these cases, we directly
encounter the problem described in [1].

RFC 7323, section 2.4 [2], says there are instances when a retracted
window can be offered, and that TCP implementations MUST ensure
that they handle a shrinking window, as specified in RFC 1122,
section 4.2.2.16 [3].  All prior RFCs on the topic of tcp window
management have made clear that sender must accept a shrunk window
from the receiver, including RFC 793 [4] and RFC 1323 [5].

This patch implements the functionality to shrink the tcp window
when necessary to keep the right edge within the memory limit by
autotuning (sk_rcvbuf).  This new functionality is enabled with
the new sysctl: net.ipv4.tcp_shrink_window

Additional information can be found at:
https://blog.cloudflare.com/unbounded-memory-usage-by-tcp-for-receive-buffers-and-how-we-fixed-it/

[1] https://www.rfc-editor.org/rfc/rfc7323#appendix-F
[2] https://www.rfc-editor.org/rfc/rfc7323#section-2.4
[3] https://www.rfc-editor.org/rfc/rfc1122#page-91
[4] https://www.rfc-editor.org/rfc/rfc793
[5] https://www.rfc-editor.org/rfc/rfc1323

Signed-off-by: Mike Freemon <mfreemon@cloudflare.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-06-17 09:53:53 +01:00
Jakub Kicinski
449f6bc17a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

net/sched/sch_taprio.c
  d636fc5dd6 ("net: sched: add rcu annotations around qdisc->qdisc_sleeping")
  dced11ef84 ("net/sched: taprio: don't overwrite "sch" variable in taprio_dump_class_stats()")

net/ipv4/sysctl_net_ipv4.c
  e209fee411 ("net/ipv4: ping_group_range: allow GID from 2147483648 to 4294967294")
  ccce324dab ("tcp: make the first N SYN RTO backoffs linear")
https://lore.kernel.org/all/20230605100816.08d41a7b@canb.auug.org.au/

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-08 11:35:14 -07:00
Eric Dumazet
ef62c0ae6d net/ipv6: convert skip_notify_on_dev_down sysctl to u8
Save a bit a space, and could help future sysctls to
use the same pattern.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 22:55:43 -07:00
Eric Dumazet
edf2e1d201 net/ipv6: fix bool/int mismatch for skip_notify_on_dev_down
skip_notify_on_dev_down ctl table expects this field
to be an int (4 bytes), not a bool (1 byte).

Because proc_dou8vec_minmax() was added in 5.13,
this patch converts skip_notify_on_dev_down to an int.

Following patch then converts the field to u8 and use proc_dou8vec_minmax().

Fixes: 7c6bb7d2fa ("net/ipv6: Add knob to skip DELROUTE message on device down")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-02 22:55:43 -07:00
David Morley
ccce324dab tcp: make the first N SYN RTO backoffs linear
Currently the SYN RTO schedule follows an exponential backoff
scheme, which can be unnecessarily conservative in cases where
there are link failures. In such cases, it's better to
aggressively try to retransmit packets, so it takes routers
less time to find a repath with a working link.

We chose a default value for this sysctl of 4, to follow
the macOS and IOS backoff scheme of 1,1,1,1,1,2,4,8, ...
MacOS and IOS have used this backoff schedule for over
a decade, since before this 2009 IETF presentation
discussed the behavior:
https://www.ietf.org/proceedings/75/slides/tcpm-1.pdf

This commit makes the SYN RTO schedule start with a number of
linear backoffs given by the following sysctl:
* tcp_syn_linear_timeouts

This changes the SYN RTO scheme to be: init_rto_val for
tcp_syn_linear_timeouts, exp backoff starting at init_rto_val

For example if init_rto_val = 1 and tcp_syn_linear_timeouts = 2, our
backoff scheme would be: 1, 1, 1, 2, 4, 8, 16, ...

Signed-off-by: David Morley <morleyd@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Tested-by: David Morley <morleyd@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20230509180558.2541885-1-morleyd.kernel@gmail.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-05-11 10:31:16 +02:00
Mahesh Bandewar
7ab75456be ipv6: add icmpv6_error_anycast_as_unicast for ICMPv6
ICMPv6 error packets are not sent to the anycast destinations and this
prevents things like traceroute from working. So create a setting similar
to ECHO when dealing with Anycast sources (icmpv6_echo_ignore_anycast).

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Maciej Żenczykowski <maze@google.com>
Link: https://lore.kernel.org/r/20230419013238.2691167-1-maheshb@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-04-20 20:07:50 -07:00
Jakub Kicinski
fd2a55e74a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Pablo Neira Ayuso says:

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

1) Fix broken listing of set elements when table has an owner.

2) Fix conntrack refcount leak in ctnetlink with related conntrack
   entries, from Hangyu Hua.

3) Fix use-after-free/double-free in ctnetlink conntrack insert path,
   from Florian Westphal.

4) Fix ip6t_rpfilter with VRF, from Phil Sutter.

5) Fix use-after-free in ebtables reported by syzbot, also from Florian.

6) Use skb->len in xt_length to deal with IPv6 jumbo packets,
   from Xin Long.

7) Fix NETLINK_LISTEN_ALL_NSID with ctnetlink, from Florian Westphal.

8) Fix memleak in {ip_,ip6_,arp_}tables in ENOMEM error case,
   from Pavel Tikhomirov.

* git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: x_tables: fix percpu counter block leak on error path when creating new netns
  netfilter: ctnetlink: make event listener tracking global
  netfilter: xt_length: use skb len to match in length_mt6
  netfilter: ebtables: fix table blob use-after-free
  netfilter: ip6t_rpfilter: Fix regression with VRF interfaces
  netfilter: conntrack: fix rmmod double-free race
  netfilter: ctnetlink: fix possible refcount leak in ctnetlink_create_conntrack()
  netfilter: nf_tables: allow to fetch set elements when table has an owner
====================

Link: https://lore.kernel.org/r/20230222092137.88637-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-02-22 21:25:23 -08:00
Florian Westphal
fdf6491193 netfilter: ctnetlink: make event listener tracking global
pernet tracking doesn't work correctly because other netns might have
set NETLINK_LISTEN_ALL_NSID on its event socket.

In this case its expected that events originating in other net
namespaces are also received.

Making pernet-tracking work while also honoring NETLINK_LISTEN_ALL_NSID
requires much more intrusive changes both in netlink and nfnetlink,
f.e. adding a 'setsockopt' callback that lets nfnetlink know that the
event socket entered (or left) ALL_NSID mode.

Move to global tracking instead: if there is an event socket anywhere
on the system, all net namespaces which have conntrack enabled and
use autobind mode will allocate the ecache extension.

netlink_has_listeners() returns false only if the given group has no
subscribers in any net namespace, the 'net' argument passed to
nfnetlink_has_listeners is only used to derive the protocol (nfnetlink),
it has no other effect.

For proper NETLINK_LISTEN_ALL_NSID-aware pernet tracking of event
listeners a new netlink_has_net_listeners() is also needed.

Fixes: 90d1daa458 ("netfilter: conntrack: add nf_conntrack_events autodetect mode")
Reported-by: Bryce Kahle <bryce.kahle@datadoghq.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2023-02-22 00:28:47 +01:00
Paolo Abeni
50bcfe8df7 net: make default_rps_mask a per netns attribute
That really was meant to be a per netns attribute from the beginning.

The idea is that once proper isolation is in place in the main
namespace, additional demux in the child namespaces will be redundant.
Let's make child netns default rps mask empty by default.

To avoid bloating the netns with a possibly large cpumask, allocate
it on-demand during the first write operation.

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-02-20 11:22:54 +00:00
Christophe JAILLET
e9b4aeed56 net: xsk: Don't include <linux/rculist.h>
There is no need to include <linux/rculist.h> here.

Prefer the less invasive <linux/types.h> which is needed for 'hlist_head'.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/88d6a1d88764cca328610854f890a9ca1f4b029e.1670086246.git.christophe.jaillet@wanadoo.fr
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-12-06 20:04:34 -08:00
Xin Long
0af0317063 sctp: add dif and sdif check in asoc and ep lookup
This patch at first adds a pernet global l3mdev_accept to decide if it
accepts the packets from a l3mdev when a SCTP socket doesn't bind to
any interface. It's set to 1 to avoid any possible incompatible issue,
and in next patch, a sysctl will be introduced to allow to change it.

Then similar to inet/udp_sk_bound_dev_eq(), sctp_sk_bound_dev_eq() is
added to check either dif or sdif is equal to sk_bound_dev_if, and to
check sid is 0 or l3mdev_accept is 1 if sk_bound_dev_if is not set.
This function is used to match a association or a endpoint, namely
called by sctp_addrs_lookup_transport() and sctp_endpoint_is_match().
All functions that needs updating are:

sctp_rcv():
  asoc:
  __sctp_rcv_lookup()
    __sctp_lookup_association() -> sctp_addrs_lookup_transport()
    __sctp_rcv_lookup_harder()
      __sctp_rcv_init_lookup()
         __sctp_lookup_association() -> sctp_addrs_lookup_transport()
      __sctp_rcv_walk_lookup()
         __sctp_rcv_asconf_lookup()
           __sctp_lookup_association() -> sctp_addrs_lookup_transport()

  ep:
  __sctp_rcv_lookup_endpoint() -> sctp_endpoint_is_match()

sctp_connect():
  sctp_endpoint_is_peeled_off()
    __sctp_lookup_association()
      sctp_has_association()
        sctp_lookup_association()
          __sctp_lookup_association() -> sctp_addrs_lookup_transport()

sctp_diag_dump_one():
  sctp_transport_lookup_process() -> sctp_addrs_lookup_transport()

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-18 11:42:54 +00:00
Kuniyuki Iwashima
9804985bf2 udp: Introduce optional per-netns hash table.
The maximum hash table size is 64K due to the nature of the protocol. [0]
It's smaller than TCP, and fewer sockets can cause a performance drop.

On an EC2 c5.24xlarge instance (192 GiB memory), after running iperf3 in
different netns, creating 32Mi sockets without data transfer in the root
netns causes regression for the iperf3's connection.

  uhash_entries		sockets		length		Gbps
	    64K		      1		     1		5.69
			    1Mi		    16		5.27
			    2Mi		    32		4.90
			    4Mi		    64		4.09
			    8Mi		   128		2.96
			   16Mi		   256		2.06
			   32Mi		   512		1.12

The per-netns hash table breaks the lengthy lists into shorter ones.  It is
useful on a multi-tenant system with thousands of netns.  With smaller hash
tables, we can look up sockets faster, isolate noisy neighbours, and reduce
lock contention.

The max size of the per-netns table is 64K as well.  This is because the
possible hash range by udp_hashfn() always fits in 64K within the same
netns and we cannot make full use of the whole buckets larger than 64K.

  /* 0 < num < 64K  ->  X < hash < X + 64K */
  (num + net_hash_mix(net)) & mask;

Also, the min size is 128.  We use a bitmap to search for an available
port in udp_lib_get_port().  To keep the bitmap on the stack and not
fire the CONFIG_FRAME_WARN error at build time, we round up the table
size to 128.

The sysctl usage is the same with TCP:

  $ dmesg | cut -d ' ' -f 6- | grep "UDP hash"
  UDP hash table entries: 65536 (order: 9, 2097152 bytes, vmalloc)

  # sysctl net.ipv4.udp_hash_entries
  net.ipv4.udp_hash_entries = 65536  # can be changed by uhash_entries

  # sysctl net.ipv4.udp_child_hash_entries
  net.ipv4.udp_child_hash_entries = 0  # disabled by default

  # ip netns add test1
  # ip netns exec test1 sysctl net.ipv4.udp_hash_entries
  net.ipv4.udp_hash_entries = -65536  # share the global table

  # sysctl -w net.ipv4.udp_child_hash_entries=100
  net.ipv4.udp_child_hash_entries = 100

  # ip netns add test2
  # ip netns exec test2 sysctl net.ipv4.udp_hash_entries
  net.ipv4.udp_hash_entries = 128  # own a per-netns table with 2^n buckets

We could optimise the hash table lookup/iteration further by removing
the netns comparison for the per-netns one in the future.  Also, we
could optimise the sparse udp_hslot layout by putting it in udp_table.

[0]: https://lore.kernel.org/netdev/4ACC2815.7010101@gmail.com/

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-16 09:43:35 +00:00
Kuniyuki Iwashima
67fb43308f udp: Set NULL to sk->sk_prot->h.udp_table.
We will soon introduce an optional per-netns hash table
for UDP.

This means we cannot use the global sk->sk_prot->h.udp_table
to fetch a UDP hash table.

Instead, set NULL to sk->sk_prot->h.udp_table for UDP and get
a proper table from net->ipv4.udp_table.

Note that we still need sk->sk_prot->h.udp_table for UDP LITE.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-11-16 09:43:35 +00:00
Mubashir Adnan Qureshi
bd456f283b tcp: add sysctls for TCP PLB parameters
PLB (Protective Load Balancing) is a host based mechanism for load
balancing across switch links. It leverages congestion signals(e.g. ECN)
from transport layer to randomly change the path of the connection
experiencing congestion. PLB changes the path of the connection by
changing the outgoing IPv6 flow label for IPv6 connections (implemented
in Linux by calling sk_rethink_txhash()). Because of this implementation
mechanism, PLB can currently only work for IPv6 traffic. For more
information, see the SIGCOMM 2022 paper:
  https://doi.org/10.1145/3544216.3544226

This commit adds new sysctl knobs and sets their default values for
TCP PLB.

Signed-off-by: Mubashir Adnan Qureshi <mubashirq@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-10-28 10:47:42 +01:00
Gustavo A. R. Silva
63a8bf8556 netns: Replace zero-length array with DECLARE_FLEX_ARRAY() helper
Zero-length arrays are deprecated and we are moving towards adopting
C99 flexible-array members, instead. So, replace zero-length arrays
declarations in anonymous union with the new DECLARE_FLEX_ARRAY()
helper macro.

This helper allows for flexible-array members in unions.

Link: https://github.com/KSPP/linux/issues/193
Link: https://github.com/KSPP/linux/issues/225
Link: https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/YzIvfGXxfjdXmIS3@work
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-28 18:51:47 -07:00
Tony Lu
0227f058aa net/smc: Unbind r/w buffer size from clcsock and make them tunable
Currently, SMC uses smc->sk.sk_{rcv|snd}buf to create buffers for
send buffer and RMB. And the values of buffer size are from tcp_{w|r}mem
in clcsock.

The buffer size from TCP socket doesn't fit SMC well. Generally, buffers
are usually larger than TCP for SMC-R/-D to get higher performance, for
they are different underlay devices and paths.

So this patch unbinds buffer size from TCP, and introduces two sysctl
knobs to tune them independently. Also, these knobs are per net
namespace and work for containers.

Signed-off-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-22 12:58:21 +02:00
Wen Gu
77eee32514 net/smc: Introduce a specific sysctl for TEST_LINK time
SMC-R tests the viability of link by sending out TEST_LINK LLC
messages over RoCE fabric when connections on link have been
idle for a time longer than keepalive interval (testlink time).

But using tcp_keepalive_time as testlink time maybe not quite
suitable because it is default no less than two hours[1], which
is too long for single link to find peer dead. The active host
will still use peer-dead link (QP) sending messages, and can't
find out until get IB_WC_RETRY_EXC_ERR error CQEs, which takes
more time than TEST_LINK timeout (SMC_LLC_WAIT_TIME) normally.

So this patch introduces a independent sysctl for SMC-R to set
link keepalive time, in order to detect link down in time. The
default value is 30 seconds.

[1] https://www.rfc-editor.org/rfc/rfc1122#page-101

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-22 12:58:21 +02:00
Kuniyuki Iwashima
d1e5e6408b tcp: Introduce optional per-netns ehash.
The more sockets we have in the hash table, the longer we spend looking
up the socket.  While running a number of small workloads on the same
host, they penalise each other and cause performance degradation.

The root cause might be a single workload that consumes much more
resources than the others.  It often happens on a cloud service where
different workloads share the same computing resource.

On EC2 c5.24xlarge instance (196 GiB memory and 524288 (1Mi / 2) ehash
entries), after running iperf3 in different netns, creating 24Mi sockets
without data transfer in the root netns causes about 10% performance
regression for the iperf3's connection.

 thash_entries		sockets		length		Gbps
	524288		      1		     1		50.7
			   24Mi		    48		45.1

It is basically related to the length of the list of each hash bucket.
For testing purposes to see how performance drops along the length,
I set 131072 (1Mi / 8) to thash_entries, and here's the result.

 thash_entries		sockets		length		Gbps
        131072		      1		     1		50.7
			    1Mi		     8		49.9
			    2Mi		    16		48.9
			    4Mi		    32		47.3
			    8Mi		    64		44.6
			   16Mi		   128		40.6
			   24Mi		   192		36.3
			   32Mi		   256		32.5
			   40Mi		   320		27.0
			   48Mi		   384		25.0

To resolve the socket lookup degradation, we introduce an optional
per-netns hash table for TCP, but it's just ehash, and we still share
the global bhash, bhash2 and lhash2.

With a smaller ehash, we can look up non-listener sockets faster and
isolate such noisy neighbours.  In addition, we can reduce lock contention.

We can control the ehash size by a new sysctl knob.  However, depending
on workloads, it will require very sensitive tuning, so we disable the
feature by default (net.ipv4.tcp_child_ehash_entries == 0).  Moreover,
we can fall back to using the global ehash in case we fail to allocate
enough memory for a new ehash.  The maximum size is 16Mi, which is large
enough that even if we have 48Mi sockets, the average list length is 3,
and regression would be less than 1%.

We can check the current ehash size by another read-only sysctl knob,
net.ipv4.tcp_ehash_entries.  A negative value means the netns shares
the global ehash (per-netns ehash is disabled or failed to allocate
memory).

  # dmesg | cut -d ' ' -f 5- | grep "established hash"
  TCP established hash table entries: 524288 (order: 10, 4194304 bytes, vmalloc hugepage)

  # sysctl net.ipv4.tcp_ehash_entries
  net.ipv4.tcp_ehash_entries = 524288  # can be changed by thash_entries

  # sysctl net.ipv4.tcp_child_ehash_entries
  net.ipv4.tcp_child_ehash_entries = 0  # disabled by default

  # ip netns add test1
  # ip netns exec test1 sysctl net.ipv4.tcp_ehash_entries
  net.ipv4.tcp_ehash_entries = -524288  # share the global ehash

  # sysctl -w net.ipv4.tcp_child_ehash_entries=100
  net.ipv4.tcp_child_ehash_entries = 100

  # ip netns add test2
  # ip netns exec test2 sysctl net.ipv4.tcp_ehash_entries
  net.ipv4.tcp_ehash_entries = 128  # own a per-netns ehash with 2^n buckets

When more than two processes in the same netns create per-netns ehash
concurrently with different sizes, we need to guarantee the size in
one of the following ways:

  1) Share the global ehash and create per-netns ehash

  First, unshare() with tcp_child_ehash_entries==0.  It creates dedicated
  netns sysctl knobs where we can safely change tcp_child_ehash_entries
  and clone()/unshare() to create a per-netns ehash.

  2) Control write on sysctl by BPF

  We can use BPF_PROG_TYPE_CGROUP_SYSCTL to allow/deny read/write on
  sysctl knobs.

Note that the global ehash allocated at the boot time is spread over
available NUMA nodes, but inet_pernet_hashinfo_alloc() will allocate
pages for each per-netns ehash depending on the current process's NUMA
policy.  By default, the allocation is done in the local node only, so
the per-netns hash table could fully reside on a random node.  Thus,
depending on the NUMA policy the netns is created with and the CPU the
current thread is running on, we could see some performance differences
for highly optimised networking applications.

Note also that the default values of two sysctl knobs depend on the ehash
size and should be tuned carefully:

  tcp_max_tw_buckets  : tcp_child_ehash_entries / 2
  tcp_max_syn_backlog : max(128, tcp_child_ehash_entries / 128)

As a bonus, we can dismantle netns faster.  Currently, while destroying
netns, we call inet_twsk_purge(), which walks through the global ehash.
It can be potentially big because it can have many sockets other than
TIME_WAIT in all netns.  Splitting ehash changes that situation, where
it's only necessary for inet_twsk_purge() to clean up TIME_WAIT sockets
in each netns.

With regard to this, we do not free the per-netns ehash in inet_twsk_kill()
to avoid UAF while iterating the per-netns ehash in inet_twsk_purge().
Instead, we do it in tcp_sk_exit_batch() after calling tcp_twsk_purge() to
keep it protocol-family-independent.

In the future, we could optimise ehash lookup/iteration further by removing
netns comparison for the per-netns ehash.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-20 10:21:50 -07:00
Kuniyuki Iwashima
e9bd0cca09 tcp: Don't allocate tcp_death_row outside of struct netns_ipv4.
We will soon introduce an optional per-netns ehash and access hash
tables via net->ipv4.tcp_death_row->hashinfo instead of &tcp_hashinfo
in most places.

It could harm the fast path because dereferences of two fields in net
and tcp_death_row might incur two extra cache line misses.  To save one
dereference, let's place tcp_death_row back in netns_ipv4 and fetch
hashinfo via net->ipv4.tcp_death_row"."hashinfo.

Note tcp_death_row was initially placed in netns_ipv4, and commit
fbb8295248 ("tcp: allocate tcp_death_row outside of struct netns_ipv4")
changed it to a pointer so that we can fire TIME_WAIT timers after freeing
net.  However, we don't do so after commit 04c494e68a ("Revert "tcp/dccp:
get rid of inet_twsk_purge()""), so we need not define tcp_death_row as a
pointer.

Also, we move refcount_dec_and_test(&tw_refcount) from tcp_sk_exit() to
tcp_sk_exit_batch() as a debug check.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-20 10:21:49 -07:00
Paolo Abeni
9f8f1933dc Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
drivers/net/ethernet/freescale/fec.h
  7d650df99d ("net: fec: add pm_qos support on imx6q platform")
  40c79ce13b ("net: fec: add stop mode support for imx8 platform")

Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-09-08 18:38:30 +02:00
Jakub Kicinski
05a5474efe Merge git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf
Florian Westphal says:

====================
netfilter: bug fixes for net

1. Fix IP address check in irc DCC conntrack helper, this should check
   the opposite direction rather than the destination address of the
   packets' direction, from David Leadbeater.

2. bridge netfilter needs to drop dst references, from Harsh Modi.
   This was fine back in the day the code was originally written,
   but nowadays various tunnels can pre-set metadata dsts on packets.

3. Remove nf_conntrack_helper sysctl and the modparam toggle, users
   need to explicitily assign the helpers to use via nftables or
   iptables.  Conntrack helpers, by design, may be used to add dynamic
   port redirections to internal machines, so its necessary to restrict
   which hosts/peers are allowed to use them.
   It was discovered that improper checking in the irc DCC helper makes
   it possible to trigger the 'please do dynamic port forward'
   from outside by embedding a 'DCC' in a PING request; if the client
   echos that back a expectation/port forward gets added.
   The auto-assign-for-everything mechanism has been in "please don't do this"
   territory since 2012.  From Pablo.

4. Fix a memory leak in the netdev hook error unwind path, also from Pablo.

* git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf:
  netfilter: nf_conntrack_irc: Fix forged IP logic
  netfilter: nf_tables: clean up hook list when offload flags check fails
  netfilter: br_netfilter: Drop dst references before setting.
  netfilter: remove nf_conntrack_helper sysctl and modparam toggles
====================

Link: https://lore.kernel.org/r/20220901071238.3044-1-fw@strlen.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-02 19:38:25 -07:00
Jakub Kicinski
60ad1100d5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
tools/testing/selftests/net/.gitignore
  sort the net-next version and use it

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-01 12:58:02 -07:00
Eric Dumazet
79e3602caa tcp: make global challenge ack rate limitation per net-ns and default disabled
Because per host rate limiting has been proven problematic (side channel
attacks can be based on it), per host rate limiting of challenge acks ideally
should be per netns and turned off by default.

This is a long due followup of following commits:

083ae30828 ("tcp: enable per-socket rate limiting of all 'challenge acks'")
f2b2c582e8 ("tcp: mitigate ACK loops for connections as tcp_sock")
75ff39ccc1 ("tcp: make challenge acks less predictable")

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Jason Baron <jbaron@akamai.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-31 19:56:48 -07:00
Pablo Neira Ayuso
b118509076 netfilter: remove nf_conntrack_helper sysctl and modparam toggles
__nf_ct_try_assign_helper() remains in place but it now requires a
template to configure the helper.

A toggle to disable automatic helper assignment was added by:

  a900689264 ("netfilter: nf_ct_helper: allow to disable automatic helper assignment")

in 2012 to address the issues described in "Secure use of iptables and
connection tracking helpers". Automatic conntrack helper assignment was
disabled by:

  3bb398d925 ("netfilter: nf_ct_helper: disable automatic helper assignment")

back in 2016.

This patch removes the sysctl and modparam toggles, users now have to
rely on explicit conntrack helper configuration via ruleset.

Update tools/testing/selftests/netfilter/nft_conntrack_helper.sh to
check that auto-assignment does not happen anymore.

Acked-by: Aaron Conole <aconole@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-08-31 12:12:32 +02:00
Stephen Hemminger
1202cdd665 Remove DECnet support from kernel
DECnet is an obsolete network protocol that receives more attention
from kernel janitors than users. It belongs in computer protocol
history museum not in Linux kernel.

It has been "Orphaned" in kernel since 2010. The iproute2 support
for DECnet was dropped in 5.0 release. The documentation link on
Sourceforge says it is abandoned there as well.

Leave the UAPI alone to keep userspace programs compiling.
This means that there is still an empty neighbour table
for AF_DECNET.

The table of /proc/sys/net entries was updated to match
current directories and reformatted to be alphabetical.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Acked-by: David Ahern <dsahern@kernel.org>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-22 14:26:30 +01:00
Florian Westphal
0b2f3212b5 netfilter: nfnetlink: re-enable conntrack expectation events
To avoid allocation of the conntrack extension area when possible,
the default behaviour was changed to only allocate the event extension
if a userspace program is subscribed to a notification group.

Problem is that while 'conntrack -E' does enable the event allocation
behind the scenes, 'conntrack -E expect' does not: no expectation events
are delivered unless user sets
"net.netfilter.nf_conntrack_events" back to 1 (always on).

Fix the autodetection to also consider EXP type group.

We need to track the 6 event groups (3+3, new/update/destroy for events and
for expectations each) independently, else we'd disable events again
if an expectation group becomes empty while there is still an active
event group.

Fixes: 2794cdb0b9 ("netfilter: nfnetlink: allow to detect if ctnetlink listeners exist")
Reported-by: Yi Chen <yiche@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
2022-08-11 18:09:54 +02:00
Jakub Kicinski
949d6b405e net: add missing includes and forward declarations under net/
This patch adds missing includes to headers under include/net.
All these problems are currently masked by the existing users
including the missing dependency before the broken header.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-22 12:53:22 +01:00
Jakub Kicinski
602ae008ab 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/IPVS updates for net-next:

1) Simplify nf_ct_get_tuple(), from Jackie Liu.

2) Add format to request_module() call, from Bill Wendling.

3) Add /proc/net/stats/nf_flowtable to monitor in-flight pending
   hardware offload objects to be processed, from Vlad Buslov.

4) Missing rcu annotation and accessors in the netfilter tree,
   from Florian Westphal.

5) Merge h323 conntrack helper nat hooks into single object,
   also from Florian.

6) A batch of update to fix sparse warnings treewide,
   from Florian Westphal.

7) Move nft_cmp_fast_mask() where it used, from Florian.

8) Missing const in nf_nat_initialized(), from James Yonan.

9) Use bitmap API for Maglev IPVS scheduler, from Christophe Jaillet.

10) Use refcount_inc instead of _inc_not_zero in flowtable,
    from Florian Westphal.

11) Remove pr_debug in xt_TPROXY, from Nathan Cancellor.

* git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf-next:
  netfilter: xt_TPROXY: remove pr_debug invocations
  netfilter: flowtable: prefer refcount_inc
  netfilter: ipvs: Use the bitmap API to allocate bitmaps
  netfilter: nf_nat: in nf_nat_initialized(), use const struct nf_conn *
  netfilter: nf_tables: move nft_cmp_fast_mask to where its used
  netfilter: nf_tables: use correct integer types
  netfilter: nf_tables: add and use BE register load-store helpers
  netfilter: nf_tables: use the correct get/put helpers
  netfilter: x_tables: use correct integer types
  netfilter: nfnetlink: add missing __be16 cast
  netfilter: nft_set_bitmap: Fix spelling mistake
  netfilter: h323: merge nat hook pointers into one
  netfilter: nf_conntrack: use rcu accessors where needed
  netfilter: nf_conntrack: add missing __rcu annotations
  netfilter: nf_flow_table: count pending offload workqueue tasks
  net/sched: act_ct: set 'net' pointer when creating new nf_flow_table
  netfilter: conntrack: use correct format characters
  netfilter: conntrack: use fallthrough to cleanup
====================

Link: https://lore.kernel.org/r/20220720230754.209053-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-20 18:05:51 -07:00
Wen Gu
4bc5008e43 net/smc: Introduce a sysctl for setting SMC-R buffer type
This patch introduces the sysctl smcr_buf_type for setting
the type of SMC-R sndbufs and RMBs.

Valid values includes:

- SMCR_PHYS_CONT_BUFS, which means use physically contiguous
  buffers for better performance and is the default value.

- SMCR_VIRT_CONT_BUFS, which means use virtually contiguous
  buffers in case of physically contiguous memory is scarce.

- SMCR_MIXED_BUFS, which means first try to use physically
  contiguous buffers. If not available, then use virtually
  contiguous buffers.

Signed-off-by: Wen Gu <guwen@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-07-18 11:19:17 +01:00
Vlad Buslov
b038177636 netfilter: nf_flow_table: count pending offload workqueue tasks
To improve hardware offload debuggability count pending 'add', 'del' and
'stats' flow_table offload workqueue tasks. Counters are incremented before
scheduling new task and decremented when workqueue handler finishes
executing. These counters allow user to diagnose congestion on hardware
offload workqueues that can happen when either CPU is starved and workqueue
jobs are executed at lower rate than new ones are added or when
hardware/driver can't keep up with the rate.

Implement the described counters as percpu counters inside new struct
netns_ft which is stored inside struct net. Expose them via new procfs file
'/proc/net/stats/nf_flowtable' that is similar to existing 'nf_conntrack'
file.

Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Signed-off-by: Oz Shlomo <ozsh@nvidia.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2022-07-11 16:25:14 +02:00
Kuniyuki Iwashima
b6e8113830 af_unix: Define a per-netns hash table.
This commit adds a per netns hash table for AF_UNIX, which size is fixed
as UNIX_HASH_SIZE for now.

The first implementation defines a per-netns hash table as a single array
of lock and list:

	struct unix_hashbucket {
		spinlock_t		lock;
		struct hlist_head	head;
	};

	struct netns_unix {
		struct unix_hashbucket	*hash;
		...
	};

But, Eric pointed out memory cost that the structure has holes because of
sizeof(spinlock_t), which is 4 (or more if LOCKDEP is enabled). [0]  It
could be expensive on a host with thousands of netns and few AF_UNIX
sockets.  For this reason, a per-netns hash table uses two dense arrays.

	struct unix_table {
		spinlock_t		*locks;
		struct hlist_head	*buckets;
	};

	struct netns_unix {
		struct unix_table	table;
		...
	};

Note the length of the list has a significant impact rather than lock
contention, so having shared locks can be an option.  But, per-netns
locks and lists still perform better than the global locks and per-netns
lists. [1]

Also, this patch adds a change so that struct netns_unix disappears from
struct net if CONFIG_UNIX is disabled.

[0]: https://lore.kernel.org/netdev/CANn89iLVxO5aqx16azNU7p7Z-nz5NrnM5QTqOzueVxEnkVTxyg@mail.gmail.com/
[1]: https://lore.kernel.org/netdev/20220617175215.1769-1-kuniyu@amazon.com/

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-22 12:59:43 +01:00
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
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
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
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
Eric Dumazet
9cb7c01342 ipv6: make ip6_rt_gc_expire an atomic_t
Reads and Writes to ip6_rt_gc_expire always have been racy,
as syzbot reported lately [1]

There is a possible risk of under-flow, leading
to unexpected high value passed to fib6_run_gc(),
although I have not observed this in the field.

Hosts hitting ip6_dst_gc() very hard are under pretty bad
state anyway.

[1]
BUG: KCSAN: data-race in ip6_dst_gc / ip6_dst_gc

read-write to 0xffff888102110744 of 4 bytes by task 13165 on cpu 1:
 ip6_dst_gc+0x1f3/0x220 net/ipv6/route.c:3311
 dst_alloc+0x9b/0x160 net/core/dst.c:86
 ip6_dst_alloc net/ipv6/route.c:344 [inline]
 icmp6_dst_alloc+0xb2/0x360 net/ipv6/route.c:3261
 mld_sendpack+0x2b9/0x580 net/ipv6/mcast.c:1807
 mld_send_cr net/ipv6/mcast.c:2119 [inline]
 mld_ifc_work+0x576/0x800 net/ipv6/mcast.c:2651
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

read-write to 0xffff888102110744 of 4 bytes by task 11607 on cpu 0:
 ip6_dst_gc+0x1f3/0x220 net/ipv6/route.c:3311
 dst_alloc+0x9b/0x160 net/core/dst.c:86
 ip6_dst_alloc net/ipv6/route.c:344 [inline]
 icmp6_dst_alloc+0xb2/0x360 net/ipv6/route.c:3261
 mld_sendpack+0x2b9/0x580 net/ipv6/mcast.c:1807
 mld_send_cr net/ipv6/mcast.c:2119 [inline]
 mld_ifc_work+0x576/0x800 net/ipv6/mcast.c:2651
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

value changed: 0x00000bb3 -> 0x00000ba9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 11607 Comm: kworker/0:21 Not tainted 5.18.0-rc1-syzkaller-00037-g42e7a03d3bad-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: mld mld_ifc_work

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20220413181333.649424-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-15 14:28:50 -07:00
David S. Miller
62f65554f5 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/
ipsec-next

Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2022-03-19

1) Delete duplicated functions that calls same xfrm_api_check.
   From Leon Romanovsky.

2) Align userland API of the default policy structure to the
   internal structures. From Nicolas Dichtel.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-19 14:49:08 +00:00
Nicolas Dichtel
b58b1f563a xfrm: rework default policy structure
This is a follow up of commit f8d858e607 ("xfrm: make user policy API
complete"). The goal is to align userland API to the internal structures.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by:  Antony Antony <antony.antony@secunet.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
2022-03-18 07:23:12 +01:00
Eric Dumazet
65466904b0 tcp: adjust TSO packet sizes based on min_rtt
Back when tcp_tso_autosize() and TCP pacing were introduced,
our focus was really to reduce burst sizes for long distance
flows.

The simple heuristic of using sk_pacing_rate/1024 has worked
well, but can lead to too small packets for hosts in the same
rack/cluster, when thousands of flows compete for the bottleneck.

Neal Cardwell had the idea of making the TSO burst size
a function of both sk_pacing_rate and tcp_min_rtt()

Indeed, for local flows, sending bigger bursts is better
to reduce cpu costs, as occasional losses can be repaired
quite fast.

This patch is based on Neal Cardwell implementation
done more than two years ago.
bbr is adjusting max_pacing_rate based on measured bandwidth,
while cubic would over estimate max_pacing_rate.

/proc/sys/net/ipv4/tcp_tso_rtt_log can be used to tune or disable
this new feature, in logarithmic steps.

Tested:

100Gbit NIC, two hosts in the same rack, 4K MTU.
600 flows rate-limited to 20000000 bytes per second.

Before patch: (TSO sizes would be limited to 20000000/1024/4096 -> 4 segments per TSO)

~# echo 0 >/proc/sys/net/ipv4/tcp_tso_rtt_log
~# nstat -n;perf stat ./super_netperf 600 -H otrv6 -l 20 -- -K dctcp -q 20000000;nstat|egrep "TcpInSegs|TcpOutSegs|TcpRetransSegs|Delivered"
  96005

 Performance counter stats for './super_netperf 600 -H otrv6 -l 20 -- -K dctcp -q 20000000':

         65,945.29 msec task-clock                #    2.845 CPUs utilized
         1,314,632      context-switches          # 19935.279 M/sec
             5,292      cpu-migrations            #   80.249 M/sec
           940,641      page-faults               # 14264.023 M/sec
   201,117,030,926      cycles                    # 3049769.216 GHz                   (83.45%)
    17,699,435,405      stalled-cycles-frontend   #    8.80% frontend cycles idle     (83.48%)
   136,584,015,071      stalled-cycles-backend    #   67.91% backend cycles idle      (83.44%)
    53,809,530,436      instructions              #    0.27  insn per cycle
                                                  #    2.54  stalled cycles per insn  (83.36%)
     9,062,315,523      branches                  # 137422329.563 M/sec               (83.22%)
       153,008,621      branch-misses             #    1.69% of all branches          (83.32%)

      23.182970846 seconds time elapsed

TcpInSegs                       15648792           0.0
TcpOutSegs                      58659110           0.0  # Average of 3.7 4K segments per TSO packet
TcpExtTCPDelivered              58654791           0.0
TcpExtTCPDeliveredCE            19                 0.0

After patch:

~# echo 9 >/proc/sys/net/ipv4/tcp_tso_rtt_log
~# nstat -n;perf stat ./super_netperf 600 -H otrv6 -l 20 -- -K dctcp -q 20000000;nstat|egrep "TcpInSegs|TcpOutSegs|TcpRetransSegs|Delivered"
  96046

 Performance counter stats for './super_netperf 600 -H otrv6 -l 20 -- -K dctcp -q 20000000':

         48,982.58 msec task-clock                #    2.104 CPUs utilized
           186,014      context-switches          # 3797.599 M/sec
             3,109      cpu-migrations            #   63.472 M/sec
           941,180      page-faults               # 19214.814 M/sec
   153,459,763,868      cycles                    # 3132982.807 GHz                   (83.56%)
    12,069,861,356      stalled-cycles-frontend   #    7.87% frontend cycles idle     (83.32%)
   120,485,917,953      stalled-cycles-backend    #   78.51% backend cycles idle      (83.24%)
    36,803,672,106      instructions              #    0.24  insn per cycle
                                                  #    3.27  stalled cycles per insn  (83.18%)
     5,947,266,275      branches                  # 121417383.427 M/sec               (83.64%)
        87,984,616      branch-misses             #    1.48% of all branches          (83.43%)

      23.281200256 seconds time elapsed

TcpInSegs                       1434706            0.0
TcpOutSegs                      58883378           0.0  # Average of 41 4K segments per TSO packet
TcpExtTCPDelivered              58878971           0.0
TcpExtTCPDeliveredCE            9664               0.0

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Link: https://lore.kernel.org/r/20220309015757.2532973-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-09 20:05:44 -08:00
Dust Li
12bbb0d163 net/smc: add sysctl for autocorking
This add a new sysctl: net.smc.autocorking_size

We can dynamically change the behaviour of autocorking
by change the value of autocorking_size.
Setting to 0 disables autocorking in SMC

Signed-off-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-01 14:25:12 +00:00
Dust Li
462791bbfa net/smc: add sysctl interface for SMC
This patch add sysctl interface to support container environment
for SMC as we talk in the mail list.

Link: https://lore.kernel.org/netdev/20220224020253.GF5443@linux.alibaba.com
Co-developed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: Dust Li <dust.li@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-01 14:25:12 +00:00
Jakub Kicinski
6b5567b1b2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
No conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-17 11:44:20 -08:00
Willem de Bruijn
0b0dff5b3b ipv6: per-netns exclusive flowlabel checks
Ipv6 flowlabels historically require a reservation before use.
Optionally in exclusive mode (e.g., user-private).

Commit 59c820b231 ("ipv6: elide flowlabel check if no exclusive
leases exist") introduced a fastpath that avoids this check when no
exclusive leases exist in the system, and thus any flowlabel use
will be granted.

That allows skipping the control operation to reserve a flowlabel
entirely. Though with a warning if the fast path fails:

  This is an optimization. Robust applications still have to revert to
  requesting leases if the fast path fails due to an exclusive lease.

Still, this is subtle. Better isolate network namespaces from each
other. Flowlabels are per-netns. Also record per-netns whether
exclusive leases are in use. Then behavior does not change based on
activity in other netns.

Changes
  v2
    - wrap in IS_ENABLED(CONFIG_IPV6) to avoid breakage if disabled

Fixes: 59c820b231 ("ipv6: elide flowlabel check if no exclusive leases exist")
Link: https://lore.kernel.org/netdev/MWHPR2201MB1072BCCCFCE779E4094837ACD0329@MWHPR2201MB1072.namprd22.prod.outlook.com/
Reported-by: Congyu Liu <liu3101@purdue.edu>
Signed-off-by: Willem de Bruijn <willemb@google.com>
Tested-by: Congyu Liu <liu3101@purdue.edu>
Link: https://lore.kernel.org/r/20220215160037.1976072-1-willemdebruijn.kernel@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-16 20:37:47 -08:00
D. Wythe
f9496b7c1b net/smc: Add global configure for handshake limitation by netlink
Although we can control SMC handshake limitation through socket options,
which means that applications who need it must modify their code. It's
quite troublesome for many existing applications. This patch modifies
the global default value of SMC handshake limitation through netlink,
providing a way to put constraint on handshake without modifies any code
for applications.

Suggested-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: D. Wythe <alibuda@linux.alibaba.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-11 11:14:58 +00:00
Eric Dumazet
8805d13ff1 ipv6/addrconf: use one delayed work per netns
Next step for using per netns inet6_addr_lst
is to have per netns work item to ultimately
call addrconf_verify_rtnl() and addrconf_verify()
with a new 'struct net*' argument.

Everything is still using the global inet6_addr_lst[] table.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-08 20:41:32 -08:00
Eric Dumazet
21a216a8fc ipv6/addrconf: allocate a per netns hash table
Add a per netns hash table and a dedicated spinlock,
first step to get rid of the global inet6_addr_lst[] one.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-08 20:41:32 -08:00
Akhmat Karakotov
e187013abe txhash: Make rethinking txhash behavior configurable via sysctl
Add a per ns sysctl that controls the txhash rethink behavior:
net.core.txrehash. When enabled, the same behavior is retained,
when disabled, rethink is not performed. Sysctl is enabled by default.

Signed-off-by: Akhmat Karakotov <hmukos@yandex-team.ru>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-31 15:05:24 +00:00
xu xin
2e9589ff80 ipv4: Namespaceify min_adv_mss sysctl knob
Different netns has different requirement on the setting of min_adv_mss
sysctl which the advertised MSS will be never lower than.

Enable min_adv_mss to be configured per network namespace.

Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-27 13:34:09 +00:00
Eric Dumazet
fbb8295248 tcp: allocate tcp_death_row outside of struct netns_ipv4
I forgot tcp had per netns tracking of timewait sockets,
and their sysctl to change the limit.

After 0dad4087a8 ("tcp/dccp: get rid of inet_twsk_purge()"),
whole struct net can be freed before last tw socket is freed.

We need to allocate a separate struct inet_timewait_death_row
object per netns.

tw_count becomes a refcount and gains associated debugging infrastructure.

BUG: KASAN: use-after-free in inet_twsk_kill+0x358/0x3c0 net/ipv4/inet_timewait_sock.c:46
Read of size 8 at addr ffff88807d5f9f40 by task kworker/1:7/3690

CPU: 1 PID: 3690 Comm: kworker/1:7 Not tainted 5.16.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events pwq_unbound_release_workfn
Call Trace:
 <IRQ>
 __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
 inet_twsk_kill+0x358/0x3c0 net/ipv4/inet_timewait_sock.c:46
 call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
 expire_timers kernel/time/timer.c:1466 [inline]
 __run_timers.part.0+0x67c/0xa30 kernel/time/timer.c:1734
 __run_timers kernel/time/timer.c:1715 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558
 invoke_softirq kernel/softirq.c:432 [inline]
 __irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:lockdep_unregister_key+0x1c9/0x250 kernel/locking/lockdep.c:6328
Code: 00 00 00 48 89 ee e8 46 fd ff ff 4c 89 f7 e8 5e c9 ff ff e8 09 cc ff ff 9c 58 f6 c4 02 75 26 41 f7 c4 00 02 00 00 74 01 fb 5b <5d> 41 5c 41 5d 41 5e 41 5f e9 19 4a 08 00 0f 0b 5b 5d 41 5c 41 5d
RSP: 0018:ffffc90004077cb8 EFLAGS: 00000206
RAX: 0000000000000046 RBX: ffff88807b61b498 RCX: 0000000000000001
RDX: dffffc0000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffff888077027128 R08: 0000000000000001 R09: ffffffff8f1ea4fc
R10: fffffbfff1ff93ee R11: 000000000000af1e R12: 0000000000000246
R13: 0000000000000000 R14: ffffffff8ffc89b8 R15: ffffffff90157fb0
 wq_unregister_lockdep kernel/workqueue.c:3508 [inline]
 pwq_unbound_release_workfn+0x254/0x340 kernel/workqueue.c:3746
 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307
 worker_thread+0x657/0x1110 kernel/workqueue.c:2454
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Allocated by task 3635:
 kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:437 [inline]
 __kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:470
 kasan_slab_alloc include/linux/kasan.h:260 [inline]
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slub.c:3230 [inline]
 slab_alloc mm/slub.c:3238 [inline]
 kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3243
 kmem_cache_zalloc include/linux/slab.h:705 [inline]
 net_alloc net/core/net_namespace.c:407 [inline]
 copy_net_ns+0x125/0x760 net/core/net_namespace.c:462
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3048
 __do_sys_unshare kernel/fork.c:3119 [inline]
 __se_sys_unshare kernel/fork.c:3117 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3117
 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

The buggy address belongs to the object at ffff88807d5f9a80
 which belongs to the cache net_namespace of size 6528
The buggy address is located 1216 bytes inside of
 6528-byte region [ffff88807d5f9a80, ffff88807d5fb400)
The buggy address belongs to the page:
page:ffffea0001f57e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807d5f9a80 pfn:0x7d5f8
head:ffffea0001f57e00 order:3 compound_mapcount:0 compound_pincount:0
memcg:ffff888070023001
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffff888010dd4f48 ffffea0001404e08 ffff8880118fd000
raw: ffff88807d5f9a80 0000000000040002 00000001ffffffff ffff888070023001
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3634, ts 119694798460, free_ts 119693556950
 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+0x1aa/0x310 mm/mempolicy.c:2271
 alloc_slab_page mm/slub.c:1799 [inline]
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x28a/0x3b0 mm/slub.c:2004
 ___slab_alloc+0x87c/0xe90 mm/slub.c:3018
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105
 slab_alloc_node mm/slub.c:3196 [inline]
 slab_alloc mm/slub.c:3238 [inline]
 kmem_cache_alloc+0x35c/0x3a0 mm/slub.c:3243
 kmem_cache_zalloc include/linux/slab.h:705 [inline]
 net_alloc net/core/net_namespace.c:407 [inline]
 copy_net_ns+0x125/0x760 net/core/net_namespace.c:462
 create_new_namespaces+0x3f6/0xb20 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0xc1/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x445/0x920 kernel/fork.c:3048
 __do_sys_unshare kernel/fork.c:3119 [inline]
 __se_sys_unshare kernel/fork.c:3117 [inline]
 __x64_sys_unshare+0x2d/0x40 kernel/fork.c:3117
 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
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
 skb_free_head net/core/skbuff.c:655 [inline]
 skb_release_data+0x65d/0x790 net/core/skbuff.c:677
 skb_release_all net/core/skbuff.c:742 [inline]
 __kfree_skb net/core/skbuff.c:756 [inline]
 consume_skb net/core/skbuff.c:914 [inline]
 consume_skb+0xc2/0x160 net/core/skbuff.c:908
 skb_free_datagram+0x1b/0x1f0 net/core/datagram.c:325
 netlink_recvmsg+0x636/0xea0 net/netlink/af_netlink.c:1998
 sock_recvmsg_nosec net/socket.c:948 [inline]
 sock_recvmsg net/socket.c:966 [inline]
 sock_recvmsg net/socket.c:962 [inline]
 ____sys_recvmsg+0x2c4/0x600 net/socket.c:2632
 ___sys_recvmsg+0x127/0x200 net/socket.c:2674
 __sys_recvmsg+0xe2/0x1a0 net/socket.c:2704
 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

Memory state around the buggy address:
 ffff88807d5f9e00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807d5f9e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807d5f9f00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff88807d5f9f80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807d5fa000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Fixes: 0dad4087a8 ("tcp/dccp: get rid of inet_twsk_purge()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reported-by: Paolo Abeni <pabeni@redhat.com>
Tested-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20220126180714.845362-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-01-26 19:00:31 -08:00
Eric Dumazet
37ba017dcc ipv4/tcp: do not use per netns ctl sockets
TCP ipv4 uses per-cpu/per-netns ctl sockets in order to send
RST and some ACK packets (on behalf of TIMEWAIT sockets).

This adds memory and cpu costs, which do not seem needed.
Now typical servers have 256 or more cores, this adds considerable
tax to netns users.

tcp sockets are used from BH context, are not receiving packets,
and do not store any persistent state but the 'struct net' pointer
in order to be able to use IPv4 output functions.

Note that I attempted a related change in the past, that had
to be hot-fixed in commit bdbbb8527b ("ipv4: tcp: get rid of ugly unicast_sock")

This patch could very well surface old bugs, on layers not
taking care of sk->sk_kern_sock properly.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-25 11:25:21 +00:00
Eric Dumazet
6a17b961ec ipv6: do not use per netns icmp sockets
Back in linux-2.6.25 (commit 98c6d1b261 "[NETNS]: Make icmpv6_sk per namespace.",
we added private per-cpu/per-netns ipv6 icmp sockets.

This adds memory and cpu costs, which do not seem needed.
Now typical servers have 256 or more cores, this adds considerable
tax to netns users.

icmp sockets are used from BH context, are not receiving packets,
and do not store any persistent state but the 'struct net' pointer.

icmpv6_xmit_lock() already makes sure to lock the chosen per-cpu
socket.

This patch has a considerable impact on the number of netns
that the worker thread in cleanup_net() can dismantle per second,
because ip6mr_sk_done() is no longer called, meaning we no longer
acquire the rtnl mutex, competing with other threads adding new netns.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-25 11:25:21 +00:00
Eric Dumazet
a15c89c703 ipv4: do not use per netns icmp sockets
Back in linux-2.6.25 (commit 4a6ad7a141 "[NETNS]: Make icmp_sk per namespace."),
we added private per-cpu/per-netns ipv4 icmp sockets.

This adds memory and cpu costs, which do not seem needed.
Now typical servers have 256 or more cores, this adds considerable
tax to netns users.

icmp sockets are used from BH context, are not receiving packets,
and do not store any persistent state but the 'struct net' pointer.

icmp_xmit_lock() already makes sure to lock the chosen per-cpu
socket.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-25 11:25:21 +00:00
xu xin
1135fad204 Namespaceify mtu_expires sysctl
This patch enables the sysctl mtu_expires to be configured per net
namespace.

Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-04 12:40:22 +00:00
xu xin
1de6b15a43 Namespaceify min_pmtu sysctl
This patch enables the sysctl min_pmtu to be configured per net
namespace.

Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-01-04 12:40:22 +00:00
Jakub Kicinski
aebb51ec3d bpf: Invert the dependency between bpf-netns.h and netns/bpf.h
netns/bpf.h gets included by netdevice.h (thru net_namespace.h)
which in turn gets included in a lot of places. We should keep
netns/bpf.h as light-weight as possible.

bpf-netns.h seems to contain more implementation details than
deserves to be included in a netns header. It needs to pull in
uapi/bpf.h to get various enum types.

Move enum netns_bpf_attach_type to netns/bpf.h and invert the
dependency. This makes netns/bpf.h fit the mold of a struct
definition header more clearly, and drops the number of objects
rebuilt when uapi/bpf.h is touched from 7.7k to 1.1k.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211230012742.770642-3-kuba@kernel.org
2021-12-29 20:03:05 -08:00
Jakub Kicinski
fc993be36f Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-02 11:44:56 -08:00
Eric Dumazet
213f5f8f31 ipv4: convert fib_num_tclassid_users to atomic_t
Before commit faa041a40b ("ipv4: Create cleanup helper for fib_nh")
changes to net->ipv4.fib_num_tclassid_users were protected by RTNL.

After the change, this is no longer the case, as free_fib_info_rcu()
runs after rcu grace period, without rtnl being held.

Fixes: faa041a40b ("ipv4: Create cleanup helper for fib_nh")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: David Ahern <dsahern@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-12-02 11:56:04 +00:00
Eric Dumazet
4199bae10c net: merge net->core.prot_inuse and net->core.sock_inuse
net->core.sock_inuse is a per cpu variable (int),
while net->core.prot_inuse is another per cpu variable
of 64 integers.

per cpu allocator tend to place them in very different places.

Grouping them together makes sense, since it makes
updates potentially faster, if hitting the same
cache line.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-11-16 13:20:45 +00:00
Florian Westphal
339031bafe netfilter: conntrack: fix boot failure with nf_conntrack.enable_hooks=1
This is a revert of
7b1957b049 ("netfilter: nf_defrag_ipv4: use net_generic infra")
and a partial revert of
8b0adbe3e3 ("netfilter: nf_defrag_ipv6: use net_generic infra").

If conntrack is builtin and kernel is booted with:
nf_conntrack.enable_hooks=1

.... kernel will fail to boot due to a NULL deref in
nf_defrag_ipv4_enable(): Its called before the ipv4 defrag initcall is
made, so net_generic() returns NULL.

To resolve this, move the user refcount back to struct net so calls
to those functions are possible even before their initcalls have run.

Fixes: 7b1957b049 ("netfilter: nf_defrag_ipv4: use net_generic infra")
Fixes: 8b0adbe3e3 ("netfilter: nf_defrag_ipv6: use net_generic infra").
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-09-28 13:04:55 +02:00
David S. Miller
9dfa859da0 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 net-next:

1) Clean up and consolidate ct ecache infrastructure by merging ct and
   expect notifiers, from Florian Westphal.

2) Missing counters and timestamp in nfnetlink_queue and _log conntrack
   information.

3) Missing error check for xt_register_template() in iptables mangle,
   as a incremental fix for the previous pull request, also from
   Florian Westphal.

4) Add netfilter hooks for the SRv6 lightweigh tunnel driver, from
   Ryoga Sato. The hooks are enabled via nf_hooks_lwtunnel sysctl
   to make sure existing netfilter rulesets do not break. There is
   a static key to disable the hooks by default.

   The pktgen_bench_xmit_mode_netif_receive.sh shows no noticeable
   impact in the seg6_input path for non-netfilter users: similar
   numbers with and without this patch.

   This is a sample of the perf report output:

    11.67%  kpktgend_0       [ipv6]                    [k] ipv6_get_saddr_eval
     7.89%  kpktgend_0       [ipv6]                    [k] __ipv6_addr_label
     7.52%  kpktgend_0       [ipv6]                    [k] __ipv6_dev_get_saddr
     6.63%  kpktgend_0       [kernel.vmlinux]          [k] asm_exc_nmi
     4.74%  kpktgend_0       [ipv6]                    [k] fib6_node_lookup_1
     3.48%  kpktgend_0       [kernel.vmlinux]          [k] pskb_expand_head
     3.33%  kpktgend_0       [ipv6]                    [k] ip6_rcv_core.isra.29
     3.33%  kpktgend_0       [ipv6]                    [k] seg6_do_srh_encap
     2.53%  kpktgend_0       [ipv6]                    [k] ipv6_dev_get_saddr
     2.45%  kpktgend_0       [ipv6]                    [k] fib6_table_lookup
     2.24%  kpktgend_0       [kernel.vmlinux]          [k] ___cache_free
     2.16%  kpktgend_0       [ipv6]                    [k] ip6_pol_route
     2.11%  kpktgend_0       [kernel.vmlinux]          [k] __ipv6_addr_type
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-30 10:57:54 +01:00
David S. Miller
fe50893aa8 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/
ipsec-next

Steffen Klassert says:

====================
pull request (net-next): ipsec-next 2021-08-27

1) Remove an unneeded extra variable in esp4 esp_ssg_unref.
   From Corey Minyard.

2) Add a configuration option to change the default behaviour
   to block traffic if there is no matching policy.
   Joint work with Christian Langrock and Antony Antony.

3) Fix a shift-out-of-bounce bug reported from syzbot.
   From Pavel Skripkin.

Please pull or let me know if there are problems.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-27 11:16:29 +01:00
Florian Westphal
bd1431db0b netfilter: ecache: remove nf_exp_event_notifier structure
Reuse the conntrack event notofier struct, this allows to remove the
extra register/unregister functions and avoids a pointer in struct net.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-08-25 12:50:38 +02:00
Jakub Kicinski
f4083a752a Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Conflicts:

drivers/net/ethernet/broadcom/bnxt/bnxt_ptp.h
  9e26680733 ("bnxt_en: Update firmware call to retrieve TX PTP timestamp")
  9e518f2580 ("bnxt_en: 1PPS functions to configure TSIO pins")
  099fdeda65 ("bnxt_en: Event handler for PPS events")

kernel/bpf/helpers.c
include/linux/bpf-cgroup.h
  a2baf4e8bb ("bpf: Fix potentially incorrect results with bpf_get_local_storage()")
  c7603cfa04 ("bpf: Add ambient BPF runtime context stored in current")

drivers/net/ethernet/mellanox/mlx5/core/pci_irq.c
  5957cc557d ("net/mlx5: Set all field of mlx5_irq before inserting it to the xarray")
  2d0b41a376 ("net/mlx5: Refcount mlx5_irq with integer")

MAINTAINERS
  7b637cd52f ("MAINTAINERS: fix Microchip CAN BUS Analyzer Tool entry typo")
  7d901a1e87 ("net: phy: add Maxlinear GPY115/21x/24x driver")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-13 06:41:22 -07:00
David S. Miller
6f45933dfe 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 net-next:

1) Use nfnetlink_unicast() instead of netlink_unicast() in nft_compat.

2) Remove call to nf_ct_l4proto_find() in flowtable offload timeout
   fixup.

3) CLUSTERIP registers ARP hook on demand, from Florian.

4) Use clusterip_net to store pernet warning, also from Florian.

5) Remove struct netns_xt, from Florian Westphal.

6) Enable ebtables hooks in initns on demand, from Florian.

7) Allow to filter conntrack netlink dump per status bits,
   from Florian Westphal.

8) Register x_tables hooks in initns on demand, from Florian.

9) Remove queue_handler from per-netns structure, again from Florian.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-11 10:22:26 +01:00
Florian Westphal
8702997074 netfilter: nf_queue: move hookfn registration out of struct net
This was done to detect when the pernet->init() function was not called
yet, by checking if net->nf.queue_handler is NULL.

Once the nfnetlink_queue module is active, all struct net pointers
contain the same address.  So place this back in nf_queue.c.

Handle the 'netns error unwind' test by checking nfnl_queue_net for a
NULL pointer and add a comment for this.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-08-10 17:32:00 +02:00
Jakub Kicinski
cc4e5eecd4 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf
Pablo Neira Ayuso says:

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

The following patchset contains Netfilter fixes for net:

1) Restrict range element expansion in ipset to avoid soft lockup,
   from Jozsef Kadlecsik.

2) Memleak in error path for nf_conntrack_bridge for IPv4 packets,
   from Yajun Deng.

3) Simplify conntrack garbage collection strategy to avoid frequent
   wake-ups, from Florian Westphal.

4) Fix NFNLA_HOOK_FUNCTION_NAME string, do not include module name.

5) Missing chain family netlink attribute in chain description
   in nfnetlink_hook.

6) Incorrect sequence number on nfnetlink_hook dumps.

7) Use netlink request family in reply message for consistency.

8) Remove offload_pickup sysctl, use conntrack for established state
   instead, from Florian Westphal.

9) Translate NFPROTO_INET/ingress to NFPROTO_NETDEV/ingress, since
   NFPROTO_INET is not exposed through nfnetlink_hook.

* git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf:
  netfilter: nfnetlink_hook: translate inet ingress to netdev
  netfilter: conntrack: remove offload_pickup sysctl again
  netfilter: nfnetlink_hook: Use same family as request message
  netfilter: nfnetlink_hook: use the sequence number of the request message
  netfilter: nfnetlink_hook: missing chain family
  netfilter: nfnetlink_hook: strip off module name from hookfn
  netfilter: conntrack: collect all entries in one cycle
  netfilter: nf_conntrack_bridge: Fix memory leak when error
  netfilter: ipset: Limit the maximal range of consecutive elements to add/delete
====================

Link: https://lore.kernel.org/r/20210806151149.6356-1-pablo@netfilter.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-06 08:44:50 -07:00
Florian Westphal
4592ee7f52 netfilter: conntrack: remove offload_pickup sysctl again
These two sysctls were added because the hardcoded defaults (2 minutes,
tcp, 30 seconds, udp) turned out to be too low for some setups.

They appeared in 5.14-rc1 so it should be fine to remove it again.

Marcelo convinced me that there should be no difference between a flow
that was offloaded vs. a flow that was not wrt. timeout handling.
Thus the default is changed to those for TCP established and UDP stream,
5 days and 120 seconds, respectively.

Marcelo also suggested to account for the timeout value used for the
offloading, this avoids increase beyond the value in the conntrack-sysctl
and will also instantly expire the conntrack entry with altered sysctls.

Example:
   nf_conntrack_udp_timeout_stream=60
   nf_flowtable_udp_timeout=60

This will remove offloaded udp flows after one minute, rather than two.

An earlier version of this patch also cleared the ASSURED bit to
allow nf_conntrack to evict the entry via early_drop (i.e., table full).
However, it looks like we can safely assume that connection timed out
via HW is still in established state, so this isn't needed.

Quoting Oz:
 [..] the hardware sends all packets with a set FIN flags to sw.
 [..] Connections that are aged in hardware are expected to be in the
 established state.

In case it turns out that back-to-sw-path transition can occur for
'dodgy' connections too (e.g., one side disappeared while software-path
would have been in RETRANS timeout), we can adjust this later.

Cc: Oz Shlomo <ozsh@nvidia.com>
Cc: Paul Blakey <paulb@nvidia.com>
Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Reviewed-by: Oz Shlomo <ozsh@nvidia.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-08-06 17:07:41 +02:00
Jakub Kicinski
0ca8d3ca45 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Build failure in drivers/net/wwan/mhi_wwan_mbim.c:
add missing parameter (0, assuming we don't want buffer pre-alloc).

Conflict in drivers/net/dsa/sja1105/sja1105_main.c between:
  589918df93 ("net: dsa: sja1105: be stateless with FDB entries on SJA1105P/Q/R/S/SJA1110 too")
  0fac6aa098 ("net: dsa: sja1105: delete the best_effort_vlan_filtering mode")

Follow the instructions from the commit message of the former commit
- removed the if conditions. When looking at commit 589918df93 ("net:
dsa: sja1105: be stateless with FDB entries on SJA1105P/Q/R/S/SJA1110 too")
note that the mask_iotag fields get removed by the following patch.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-08-05 15:08:47 -07:00
David S. Miller
d00551b402 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec
Steffen Klassert says:

====================
pull request (net): ipsec 2021-08-04

1) Fix a sysbot reported memory leak in xfrm_user_rcv_msg.
   From Pavel Skripkin.

2) Revert "xfrm: policy: Read seqcount outside of rcu-read side
   in xfrm_policy_lookup_bytype". This commit tried to fix a
   lockin bug, but only cured some of the symptoms. A proper
   fix is applied on top of this revert.

3) Fix a locking bug on xfrm state hash resize. A recent change
   on sequence counters accidentally repaced a spinlock by a mutex.
   Fix from Frederic Weisbecker.

4) Fix possible user-memory-access in xfrm_user_rcv_msg_compat().
   From Dmitry Safonov.

5) Add initialiation sefltest fot xfrm_spdattr_type_t.
   From Dmitry Safonov.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2021-08-04 10:45:41 +01:00
Florian Westphal
f2e3778db7 netfilter: remove xt pernet data
clusterip is now handled via net_generic.

NOTRACK is tiny compared to rest of xt_CT feature set, even the existing
deprecation warning is bigger than the actual functionality.

Just remove the warning, its not worth keeping/adding a net_generic one.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2021-08-01 12:00:51 +02:00
Matt Johnston
03f2bbc4ee mctp: Allow per-netns default networks
Currently we have a compile-time default network
(MCTP_INITIAL_DEFAULT_NET). This change introduces a default_net field
on the net namespace, allowing future configuration for new interfaces.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Jeremy Kerr
833ef3b91d mctp: Populate socket implementation
Start filling-out the socket syscalls: bind, sendmsg & recvmsg.

This requires an input route implementation, so we add to
mctp_route_input, allowing lookups on binds & message tags. This just
handles single-packet messages at present, we will add fragmentation in
a future change.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Matt Johnston
4d8b931928 mctp: Add neighbour implementation
Add an initial neighbour table implementation, to be used in the route
output path.

Signed-off-by: Matt Johnston <matt@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00
Jeremy Kerr
889b7da23a mctp: Add initial routing framework
Add a simple routing table, and a couple of route output handlers, and
the mctp packet_type & handler.

Includes changes from Matt Johnston <matt@codeconstruct.com.au>.

Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-29 15:06:50 +01:00