Commit Graph

12409 Commits

Author SHA1 Message Date
Jason Xing
b533fb9cf4 rstreason: make it work in trace world
At last, we should let it work by introducing this reset reason in
trace world.

One of the possible expected outputs is:
... tcp_send_reset: skbaddr=xxx skaddr=xxx src=xxx dest=xxx
state=TCP_ESTABLISHED reason=NOT_SPECIFIED

Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-04-26 15:34:01 +02:00
Jason Xing
120391ef9c tcp: support rstreason for passive reset
Reuse the dropreason logic to show the exact reason of tcp reset,
so we can finally display the corresponding item in enum sk_reset_reason
instead of reinventing new reset reasons. This patch replaces all
the prior NOT_SPECIFIED reasons.

Signed-off-by: Jason Xing <kernelxing@tencent.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-04-26 15:34:00 +02:00
Jason Xing
5691276b39 rstreason: prepare for active reset
Like what we did to passive reset:
only passing possible reset reason in each active reset path.

No functional changes.

Signed-off-by: Jason Xing <kernelxing@tencent.com>
Acked-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-04-26 15:34:00 +02:00
Jason Xing
6be49deaa0 rstreason: prepare for passive reset
Adjust the parameter and support passing reason of reset which
is for now NOT_SPECIFIED. No functional changes.

Signed-off-by: Jason Xing <kernelxing@tencent.com>
Acked-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-04-26 15:34:00 +02:00
Eric Dumazet
c4e86b4363 net: add two more call_rcu_hurry()
I had failures with pmtu.sh selftests lately,
with netns dismantles firing ref_tracking alerts [1].

After much debugging, I found that some queued
rcu callbacks were delayed by minutes, because
of CONFIG_RCU_LAZY=y option.

Joel Fernandes had a similar issue in the past,
fixed with commit 483c26ff63 ("net: Use call_rcu_hurry()
for dst_release()")

In this commit, I make sure nexthop_free_rcu()
and free_fib_info_rcu() are not delayed too much
because they both can release device references.

tools/testing/selftests/net/pmtu.sh no longer fails.

Traces were:

[  968.179860] ref_tracker: veth_A-R1@00000000d0ff3fe2 has 3/5 users at
                    dst_alloc+0x76/0x160
                    ip6_dst_alloc+0x25/0x80
                    ip6_pol_route+0x2a8/0x450
                    ip6_pol_route_output+0x1f/0x30
                    fib6_rule_lookup+0x163/0x270
                    ip6_route_output_flags+0xda/0x190
                    ip6_dst_lookup_tail.constprop.0+0x1d0/0x260
                    ip6_dst_lookup_flow+0x47/0xa0
                    udp_tunnel6_dst_lookup+0x158/0x210
                    vxlan_xmit_one+0x4c2/0x1550 [vxlan]
                    vxlan_xmit+0x52d/0x14f0 [vxlan]
                    dev_hard_start_xmit+0x7b/0x1e0
                    __dev_queue_xmit+0x20b/0xe40
                    ip6_finish_output2+0x2ea/0x6e0
                    ip6_finish_output+0x143/0x320
                    ip6_output+0x74/0x140

[  968.179860] ref_tracker: veth_A-R1@00000000d0ff3fe2 has 1/5 users at
                    netdev_get_by_index+0xc0/0xe0
                    fib6_nh_init+0x1a9/0xa90
                    rtm_new_nexthop+0x6fa/0x1580
                    rtnetlink_rcv_msg+0x155/0x3e0
                    netlink_rcv_skb+0x61/0x110
                    rtnetlink_rcv+0x19/0x20
                    netlink_unicast+0x23f/0x380
                    netlink_sendmsg+0x1fc/0x430
                    ____sys_sendmsg+0x2ef/0x320
                    ___sys_sendmsg+0x86/0xd0
                    __sys_sendmsg+0x67/0xc0
                    __x64_sys_sendmsg+0x21/0x30
                    x64_sys_call+0x252/0x2030
                    do_syscall_64+0x6c/0x190
                    entry_SYSCALL_64_after_hwframe+0x76/0x7e

[  968.179860] ref_tracker: veth_A-R1@00000000d0ff3fe2 has 1/5 users at
                    ipv6_add_dev+0x136/0x530
                    addrconf_notify+0x19d/0x770
                    notifier_call_chain+0x65/0xd0
                    raw_notifier_call_chain+0x1a/0x20
                    call_netdevice_notifiers_info+0x54/0x90
                    register_netdevice+0x61e/0x790
                    veth_newlink+0x230/0x440
                    __rtnl_newlink+0x7d2/0xaa0
                    rtnl_newlink+0x4c/0x70
                    rtnetlink_rcv_msg+0x155/0x3e0
                    netlink_rcv_skb+0x61/0x110
                    rtnetlink_rcv+0x19/0x20
                    netlink_unicast+0x23f/0x380
                    netlink_sendmsg+0x1fc/0x430
                    ____sys_sendmsg+0x2ef/0x320
                    ___sys_sendmsg+0x86/0xd0
....
[ 1079.316024]  ? show_regs+0x68/0x80
[ 1079.316087]  ? __warn+0x8c/0x140
[ 1079.316103]  ? ref_tracker_free+0x1a0/0x270
[ 1079.316117]  ? report_bug+0x196/0x1c0
[ 1079.316135]  ? handle_bug+0x42/0x80
[ 1079.316149]  ? exc_invalid_op+0x1c/0x70
[ 1079.316162]  ? asm_exc_invalid_op+0x1f/0x30
[ 1079.316193]  ? ref_tracker_free+0x1a0/0x270
[ 1079.316208]  ? _raw_spin_unlock+0x1a/0x40
[ 1079.316222]  ? free_unref_page+0x126/0x1a0
[ 1079.316239]  ? destroy_large_folio+0x69/0x90
[ 1079.316251]  ? __folio_put+0x99/0xd0
[ 1079.316276]  dst_dev_put+0x69/0xd0
[ 1079.316308]  fib6_nh_release_dsts.part.0+0x3d/0x80
[ 1079.316327]  fib6_nh_release+0x45/0x70
[ 1079.316340]  nexthop_free_rcu+0x131/0x170
[ 1079.316356]  rcu_do_batch+0x1ee/0x820
[ 1079.316370]  ? rcu_do_batch+0x179/0x820
[ 1079.316388]  rcu_core+0x1aa/0x4d0
[ 1079.316405]  rcu_core_si+0x12/0x20
[ 1079.316417]  __do_softirq+0x13a/0x3dc
[ 1079.316435]  __irq_exit_rcu+0xa3/0x110
[ 1079.316449]  irq_exit_rcu+0x12/0x30
[ 1079.316462]  sysvec_apic_timer_interrupt+0x5b/0xe0
[ 1079.316474]  asm_sysvec_apic_timer_interrupt+0x1f/0x30
[ 1079.316569] RIP: 0033:0x7f06b65c63f0

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/20240423205408.39632-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-25 15:24:23 -07:00
Jakub Kicinski
2bd87951de Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

drivers/net/ethernet/ti/icssg/icssg_prueth.c

net/mac80211/chan.c
  89884459a0 ("wifi: mac80211: fix idle calculation with multi-link")
  87f5500285 ("wifi: mac80211: simplify ieee80211_assign_link_chanctx()")
https://lore.kernel.org/all/20240422105623.7b1fbda2@canb.auug.org.au/

net/unix/garbage.c
  1971d13ffa ("af_unix: Suppress false-positive lockdep splat for spin_lock() in __unix_gc().")
  4090fa373f ("af_unix: Replace garbage collection algorithm.")

drivers/net/ethernet/ti/icssg/icssg_prueth.c
drivers/net/ethernet/ti/icssg/icssg_common.c
  4dcd0e83ea ("net: ti: icssg-prueth: Fix signedness bug in prueth_init_rx_chns()")
  e2dc7bfd67 ("net: ti: icssg-prueth: Move common functions into a separate file")

No adjacent changes.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-25 12:41:37 -07:00
Eric Dumazet
ec00ed472b tcp: avoid premature drops in tcp_add_backlog()
While testing TCP performance with latest trees,
I saw suspect SOCKET_BACKLOG drops.

tcp_add_backlog() computes its limit with :

    limit = (u32)READ_ONCE(sk->sk_rcvbuf) +
            (u32)(READ_ONCE(sk->sk_sndbuf) >> 1);
    limit += 64 * 1024;

This does not take into account that sk->sk_backlog.len
is reset only at the very end of __release_sock().

Both sk->sk_backlog.len and sk->sk_rmem_alloc could reach
sk_rcvbuf in normal conditions.

We should double sk->sk_rcvbuf contribution in the formula
to absorb bubbles in the backlog, which happen more often
for very fast flows.

This change maintains decent protection against abuses.

Fixes: c377411f24 ("net: sk_add_backlog() take rmem_alloc into account")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240423125620.3309458-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-25 12:15:02 -07:00
Philo Lu
2bf90a57f0 tcp: update sacked after tracepoint in __tcp_retransmit_skb
Marking TCP_SKB_CB(skb)->sacked with TCPCB_EVER_RETRANS after the
traceopint (trace_tcp_retransmit_skb), then we can get the
retransmission efficiency by counting skbs w/ and w/o TCPCB_EVER_RETRANS
mark in this tracepoint.

We have discussed to achieve this with BPF_SOCK_OPS in [0], and using
tracepoint is thought to be a better solution.

[0]
https://lore.kernel.org/all/20240417124622.35333-1-lulie@linux.alibaba.com/

Signed-off-by: Philo Lu <lulie@linux.alibaba.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-25 08:52:12 +01:00
Hyunwoo Kim
80e679b352 tcp: Fix Use-After-Free in tcp_ao_connect_init
Since call_rcu, which is called in the hlist_for_each_entry_rcu traversal
of tcp_ao_connect_init, is not part of the RCU read critical section, it
is possible that the RCU grace period will pass during the traversal and
the key will be free.

To prevent this, it should be changed to hlist_for_each_entry_safe.

Fixes: 7c2ffaf21b ("net/tcp: Calculate TCP-AO traffic keys")
Signed-off-by: Hyunwoo Kim <v4bel@theori.io>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Dmitry Safonov <0x7f454c46@gmail.com>
Link: https://lore.kernel.org/r/ZiYu9NJ/ClR8uSkH@v4bel-B760M-AORUS-ELITE-AX
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-23 19:06:39 -07:00
Eric Dumazet
58a4c9b1e5 ipv4: check for NULL idev in ip_route_use_hint()
syzbot was able to trigger a NULL deref in fib_validate_source()
in an old tree [1].

It appears the bug exists in latest trees.

All calls to __in_dev_get_rcu() must be checked for a NULL result.

[1]
general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 2 PID: 3257 Comm: syz-executor.3 Not tainted 5.10.0-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
 RIP: 0010:fib_validate_source+0xbf/0x15a0 net/ipv4/fib_frontend.c:425
Code: 18 f2 f2 f2 f2 42 c7 44 20 23 f3 f3 f3 f3 48 89 44 24 78 42 c6 44 20 27 f3 e8 5d 88 48 fc 4c 89 e8 48 c1 e8 03 48 89 44 24 18 <42> 80 3c 20 00 74 08 4c 89 ef e8 d2 15 98 fc 48 89 5c 24 10 41 bf
RSP: 0018:ffffc900015fee40 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88800f7a4000 RCX: ffff88800f4f90c0
RDX: 0000000000000000 RSI: 0000000004001eac RDI: ffff8880160c64c0
RBP: ffffc900015ff060 R08: 0000000000000000 R09: ffff88800f7a4000
R10: 0000000000000002 R11: ffff88800f4f90c0 R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000000000 R15: ffff88800f7a4000
FS:  00007f938acfe6c0(0000) GS:ffff888058c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f938acddd58 CR3: 000000001248e000 CR4: 0000000000352ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
  ip_route_use_hint+0x410/0x9b0 net/ipv4/route.c:2231
  ip_rcv_finish_core+0x2c4/0x1a30 net/ipv4/ip_input.c:327
  ip_list_rcv_finish net/ipv4/ip_input.c:612 [inline]
  ip_sublist_rcv+0x3ed/0xe50 net/ipv4/ip_input.c:638
  ip_list_rcv+0x422/0x470 net/ipv4/ip_input.c:673
  __netif_receive_skb_list_ptype net/core/dev.c:5572 [inline]
  __netif_receive_skb_list_core+0x6b1/0x890 net/core/dev.c:5620
  __netif_receive_skb_list net/core/dev.c:5672 [inline]
  netif_receive_skb_list_internal+0x9f9/0xdc0 net/core/dev.c:5764
  netif_receive_skb_list+0x55/0x3e0 net/core/dev.c:5816
  xdp_recv_frames net/bpf/test_run.c:257 [inline]
  xdp_test_run_batch net/bpf/test_run.c:335 [inline]
  bpf_test_run_xdp_live+0x1818/0x1d00 net/bpf/test_run.c:363
  bpf_prog_test_run_xdp+0x81f/0x1170 net/bpf/test_run.c:1376
  bpf_prog_test_run+0x349/0x3c0 kernel/bpf/syscall.c:3736
  __sys_bpf+0x45c/0x710 kernel/bpf/syscall.c:5115
  __do_sys_bpf kernel/bpf/syscall.c:5201 [inline]
  __se_sys_bpf kernel/bpf/syscall.c:5199 [inline]
  __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5199

Fixes: 02b2494161 ("ipv4: use dst hint for ipv4 list receive")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240421184326.1704930-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-23 19:02:57 -07:00
Eric Dumazet
8ee602c635 tcp: try to send bigger TSO packets
While investigating TCP performance, I found that TCP would
sometimes send big skbs followed by a single MSS skb,
in a 'locked' pattern.

For instance, BIG TCP is enabled, MSS is set to have 4096 bytes
of payload per segment. gso_max_size is set to 181000.

This means that an optimal TCP packet size should contain
44 * 4096 = 180224 bytes of payload,

However, I was seeing packets sizes interleaved in this pattern:

172032, 8192, 172032, 8192, 172032, 8192, <repeat>

tcp_tso_should_defer() heuristic is defeated, because after a split of
a packet in write queue for whatever reason (this might be a too small
CWND or a small enough pacing_rate),
the leftover packet in the queue is smaller than the optimal size.

It is time to try to make 'leftover packets' bigger so that
tcp_tso_should_defer() can give its full potential.

After this patch, we can see the following output:

14:13:34.009273 IP6 sender > receiver: Flags [P.], seq 4048380:4098360, ack 1, win 256, options [nop,nop,TS val 3425678144 ecr 1561784500], length 49980
14:13:34.010272 IP6 sender > receiver: Flags [P.], seq 4098360:4148340, ack 1, win 256, options [nop,nop,TS val 3425678145 ecr 1561784501], length 49980
14:13:34.011271 IP6 sender > receiver: Flags [P.], seq 4148340:4198320, ack 1, win 256, options [nop,nop,TS val 3425678146 ecr 1561784502], length 49980
14:13:34.012271 IP6 sender > receiver: Flags [P.], seq 4198320:4248300, ack 1, win 256, options [nop,nop,TS val 3425678147 ecr 1561784503], length 49980
14:13:34.013272 IP6 sender > receiver: Flags [P.], seq 4248300:4298280, ack 1, win 256, options [nop,nop,TS val 3425678148 ecr 1561784504], length 49980
14:13:34.014271 IP6 sender > receiver: Flags [P.], seq 4298280:4348260, ack 1, win 256, options [nop,nop,TS val 3425678149 ecr 1561784505], length 49980
14:13:34.015272 IP6 sender > receiver: Flags [P.], seq 4348260:4398240, ack 1, win 256, options [nop,nop,TS val 3425678150 ecr 1561784506], length 49980
14:13:34.016270 IP6 sender > receiver: Flags [P.], seq 4398240:4448220, ack 1, win 256, options [nop,nop,TS val 3425678151 ecr 1561784507], length 49980
14:13:34.017269 IP6 sender > receiver: Flags [P.], seq 4448220:4498200, ack 1, win 256, options [nop,nop,TS val 3425678152 ecr 1561784508], length 49980
14:13:34.018276 IP6 sender > receiver: Flags [P.], seq 4498200:4548180, ack 1, win 256, options [nop,nop,TS val 3425678153 ecr 1561784509], length 49980
14:13:34.019259 IP6 sender > receiver: Flags [P.], seq 4548180:4598160, ack 1, win 256, options [nop,nop,TS val 3425678154 ecr 1561784510], length 49980

With 200 concurrent flows on a 100Gbit NIC, we can see a reduction
of TSO packets (and ACK packets) of about 30 %.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240418214600.1291486-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-22 14:25:28 -07:00
Eric Dumazet
d5b38a71d3 tcp: call tcp_set_skb_tso_segs() from tcp_write_xmit()
tcp_write_xmit() calls tcp_init_tso_segs()
to set gso_size and gso_segs on the packet.

tcp_init_tso_segs() requires the stack to maintain
an up to date tcp_skb_pcount(), and this makes sense
for packets in rtx queue. Not so much for packets
still in the write queue.

In the following patch, we don't want to deal with
tcp_skb_pcount() when moving payload from 2nd
skb to 1st skb in the write queue.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240418214600.1291486-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-22 14:25:27 -07:00
Eric Dumazet
22555032c5 tcp: remove dubious FIN exception from tcp_cwnd_test()
tcp_cwnd_test() has a special handing for the last packet in
the write queue if it is smaller than one MSS and has the FIN flag.

This is in violation of TCP RFC, and seems quite dubious.

This packet can be sent only if the current CWND is bigger
than the number of packets in flight.

Making tcp_cwnd_test() result independent of the first skb
in the write queue is needed for the last patch of the series.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240418214600.1291486-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-22 14:25:27 -07:00
Eric Dumazet
c51db4ac10 tcp: do not export tcp_twsk_purge()
After commit 1eeb504357 ("tcp/dccp: do not care about
families in inet_twsk_purge()") tcp_twsk_purge() is
no longer potentially called from a module.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-22 11:53:51 +01:00
Eric Dumazet
c58e88d490 icmp: prevent possible NULL dereferences from icmp_build_probe()
First problem is a double call to __in_dev_get_rcu(), because
the second one could return NULL.

if (__in_dev_get_rcu(dev) && __in_dev_get_rcu(dev)->ifa_list)

Second problem is a read from dev->ip6_ptr with no NULL check:

if (!list_empty(&rcu_dereference(dev->ip6_ptr)->addr_list))

Use the correct RCU API to fix these.

v2: add missing include <net/addrconf.h>

Fixes: d329ea5bd8 ("icmp: add response to RFC 8335 PROBE messages")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Andreas Roeseler <andreas.a.roeseler@gmail.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-22 10:00:31 +01:00
Thomas Weißschuh
bfa858f220 sysctl: treewide: constify ctl_table_header::ctl_table_arg
To be able to constify instances of struct ctl_tables it is necessary to
remove ways through which non-const versions are exposed from the
sysctl core.
One of these is the ctl_table_arg member of struct ctl_table_header.

Constify this reference as a prerequisite for the full constification of
struct ctl_table instances.
No functional change.

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-22 08:56:31 +01:00
Yick Xie
680d11f6e5 udp: preserve the connected status if only UDP cmsg
If "udp_cmsg_send()" returned 0 (i.e. only UDP cmsg),
"connected" should not be set to 0. Otherwise it stops
the connected socket from using the cached route.

Fixes: 2e8de85763 ("udp: add gso segment cmsg")
Signed-off-by: Yick Xie <yick.xie@gmail.com>
Cc: stable@vger.kernel.org
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20240418170610.867084-1-yick.xie@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-19 20:10:15 -07:00
Jakub Kicinski
41e3ddb291 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

include/trace/events/rpcgss.h
  386f4a7379 ("trace: events: cleanup deprecated strncpy uses")
  a4833e3aba ("SUNRPC: Fix rpcgss_context trace event acceptor field")

Adjacent changes:

drivers/net/ethernet/intel/ice/ice_tc_lib.c
  2cca35f5dd ("ice: Fix checking for unsupported keys on non-tunnel device")
  784feaa65d ("ice: Add support for PFCP hardware offload in switchdev")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-18 13:12:24 -07:00
Eric Dumazet
ba3de6d803 tcp_metrics: use parallel_ops for tcp_metrics_nl_family
TCP_METRICS_CMD_GET and TCP_METRICS_CMD_DEL use their
own locking (tcp_metrics_lock and RCU),
they do not need genl_mutex protection.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240416162025.1251547-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-17 18:31:53 -07:00
Eric Dumazet
ade1c9cc40 tcp_metrics: fix tcp_metrics_nl_dump() return value
Change tcp_metrics_nl_dump() to return 0 at the end
of a dump so that NLMSG_DONE can be appended
to the current skb, saving one recvmsg() system call.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240416161112.1199265-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-17 18:30:58 -07:00
Eric Dumazet
2bd99aef1b tcp: accept bare FIN packets under memory pressure
Andrew Oates reported that some macOS hosts could repeatedly
send FIN packets even if the remote peer drops them and
send back DUP ACK RWIN 0 packets.

<quoting Andrew>

 20:27:16.968254 gif0  In  IP macos > victim: Flags [SEW], seq 1950399762, win 65535, options [mss 1460,nop,wscale 6,nop,nop,TS val 501897188 ecr 0,sackOK,eol], length 0
 20:27:16.968339 gif0  Out IP victim > macos: Flags [S.E], seq 2995489058, ack 1950399763, win 1448, options [mss 1460,sackOK,TS val 3829877593 ecr 501897188,nop,wscale 0], length 0
 20:27:16.968833 gif0  In  IP macos > victim: Flags [.], ack 1, win 2058, options [nop,nop,TS val 501897188 ecr 3829877593], length 0
 20:27:16.968885 gif0  In  IP macos > victim: Flags [P.], seq 1:1449, ack 1, win 2058, options [nop,nop,TS val 501897188 ecr 3829877593], length 1448
 20:27:16.968896 gif0  Out IP victim > macos: Flags [.], ack 1449, win 0, options [nop,nop,TS val 3829877593 ecr 501897188], length 0
 20:27:19.454593 gif0  In  IP macos > victim: Flags [F.], seq 1449, ack 1, win 2058, options [nop,nop,TS val 501899674 ecr 3829877593], length 0
 20:27:19.454675 gif0  Out IP victim > macos: Flags [.], ack 1449, win 0, options [nop,nop,TS val 3829880079 ecr 501899674], length 0
 20:27:19.455116 gif0  In  IP macos > victim: Flags [F.], seq 1449, ack 1, win 2058, options [nop,nop,TS val 501899674 ecr 3829880079], length 0

 The retransmits/dup-ACKs then repeat in a tight loop.

</quoting Andrew>

RFC 9293 3.4. Sequence Numbers states :

  Note that when the receive window is zero no segments should be
  acceptable except ACK segments.  Thus, it is be possible for a TCP to
  maintain a zero receive window while transmitting data and receiving
  ACKs.  However, even when the receive window is zero, a TCP must
  process the RST and URG fields of all incoming segments.

Even if we could consider a bare FIN.ACK packet to be an ACK in RFC terms,
the retransmits should use exponential backoff.

Accepting the FIN in linux does not add extra memory costs,
because the FIN flag will simply be merged to the tail skb in
the receive queue, and incoming packet is freed.

Reported-by: Andrew Oates <aoates@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Christoph Paasch <cpaasch@apple.com>
Cc: Vidhi Goel <vidhi_goel@apple.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-17 12:58:40 +01:00
Gabriel Krisman Bertazi
50aee97d15 udp: Avoid call to compute_score on multiple sites
We've observed a 7-12% performance regression in iperf3 UDP ipv4 and
ipv6 tests with multiple sockets on Zen3 cpus, which we traced back to
commit f0ea27e7bf ("udp: re-score reuseport groups when connected
sockets are present").  The failing tests were those that would spawn
UDP sockets per-cpu on systems that have a high number of cpus.

Unsurprisingly, it is not caused by the extra re-scoring of the reused
socket, but due to the compiler no longer inlining compute_score, once
it has the extra call site in udp4_lib_lookup2.  This is augmented by
the "Safe RET" mitigation for SRSO, needed in our Zen3 cpus.

We could just explicitly inline it, but compute_score() is quite a large
function, around 300b.  Inlining in two sites would almost double
udp4_lib_lookup2, which is a silly thing to do just to workaround a
mitigation.  Instead, this patch shuffles the code a bit to avoid the
multiple calls to compute_score.  Since it is a static function used in
one spot, the compiler can safely fold it in, as it did before, without
increasing the text size.

With this patch applied I ran my original iperf3 testcases.  The failing
cases all looked like this (ipv4):
	iperf3 -c 127.0.0.1 --udp -4 -f K -b $R -l 8920 -t 30 -i 5 -P 64 -O 2

where $R is either 1G/10G/0 (max, unlimited).  I ran 3 times each.
baseline is v6.9-rc3. harmean == harmonic mean; CV == coefficient of
variation.

ipv4:
                 1G                10G                  MAX
	    HARMEAN  (CV)      HARMEAN  (CV)    HARMEAN     (CV)
baseline 1743852.66(0.0208) 1725933.02(0.0167) 1705203.78(0.0386)
patched  1968727.61(0.0035) 1962283.22(0.0195) 1923853.50(0.0256)

ipv6:
                 1G                10G                  MAX
	    HARMEAN  (CV)      HARMEAN  (CV)    HARMEAN     (CV)
baseline 1729020.03(0.0028) 1691704.49(0.0243) 1692251.34(0.0083)
patched  1900422.19(0.0067) 1900968.01(0.0067) 1568532.72(0.1519)

This restores the performance we had before the change above with this
benchmark.  We obviously don't expect any real impact when mitigations
are disabled, but just to be sure it also doesn't regresses:

mitigations=off ipv4:
                 1G                10G                  MAX
	    HARMEAN  (CV)      HARMEAN  (CV)    HARMEAN     (CV)
baseline 3230279.97(0.0066) 3229320.91(0.0060) 2605693.19(0.0697)
patched  3242802.36(0.0073) 3239310.71(0.0035) 2502427.19(0.0882)

Cc: Lorenz Bauer <lmb@isovalent.com>
Fixes: f0ea27e7bf ("udp: re-score reuseport groups when connected sockets are present")
Signed-off-by: Gabriel Krisman Bertazi <krisman@suse.de>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-15 11:59:58 +01:00
Jakub Kicinski
460b0d33cf inet: bring NLM_DONE out to a separate recv() again
Commit under Fixes optimized the number of recv() calls
needed during RTM_GETROUTE dumps, but we got multiple
reports of applications hanging on recv() calls.
Applications expect that a route dump will be terminated
with a recv() reading an individual NLM_DONE message.

Coalescing NLM_DONE is perfectly legal in netlink,
but even tho reporters fixed the code in respective
projects, chances are it will take time for those
applications to get updated. So revert to old behavior
(for now)?

Old kernel (5.19):

 $ ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_route.yaml \
            --dump getroute --json '{"rtm-family": 2}'
 Recv: read 692 bytes, 11 messages
   nl_len = 68 (52) nl_flags = 0x22 nl_type = 24
 ...
   nl_len = 60 (44) nl_flags = 0x22 nl_type = 24
 Recv: read 20 bytes, 1 messages
   nl_len = 20 (4) nl_flags = 0x2 nl_type = 3

Before (6.9-rc2):

 $ ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_route.yaml \
            --dump getroute --json '{"rtm-family": 2}'
 Recv: read 712 bytes, 12 messages
   nl_len = 68 (52) nl_flags = 0x22 nl_type = 24
 ...
   nl_len = 60 (44) nl_flags = 0x22 nl_type = 24
   nl_len = 20 (4) nl_flags = 0x2 nl_type = 3

After:

 $ ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_route.yaml \
            --dump getroute --json '{"rtm-family": 2}'
 Recv: read 692 bytes, 11 messages
   nl_len = 68 (52) nl_flags = 0x22 nl_type = 24
 ...
   nl_len = 60 (44) nl_flags = 0x22 nl_type = 24
 Recv: read 20 bytes, 1 messages
   nl_len = 20 (4) nl_flags = 0x2 nl_type = 3

Reported-by: Stefano Brivio <sbrivio@redhat.com>
Link: https://lore.kernel.org/all/20240315124808.033ff58d@elisabeth
Reported-by: Ilya Maximets <i.maximets@ovn.org>
Link: https://lore.kernel.org/all/02b50aae-f0e9-47a4-8365-a977a85975d3@ovn.org
Fixes: 4ce5dc9316 ("inet: switch inet_dump_fib() to RCU protection")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Tested-by: Ilya Maximets <i.maximets@ovn.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-15 10:25:27 +01:00
Eric Dumazet
d13b059623 tcp: small optimization when TCP_TW_SYN is processed
When TCP_TW_SYN is processed, we perform a lookup to find
a listener and jump back in tcp_v6_rcv() and tcp_v4_rcv()

Paolo suggested that we do not have to check if the
found socket is a TIME_WAIT or NEW_SYN_RECV one.

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/netdev/68085c8a84538cacaac991415e4ccc72f45e76c2.camel@redhat.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Link: https://lore.kernel.org/r/20240411082530.907113-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-12 19:06:50 -07:00
Guillaume Nault
5618603f5d ipv4: Remove RTO_ONLINK.
RTO_ONLINK was a flag used in ->flowi4_tos that allowed to alter the
scope of an IPv4 route lookup. Setting this flag was equivalent to
specifying RT_SCOPE_LINK in ->flowi4_scope.

With commit ec20b28300 ("ipv4: Set scope explicitly in
ip_route_output()."), the last users of RTO_ONLINK have been removed.
Therefore, we can now drop the code that checked this bit and stop
modifying ->flowi4_scope in ip_route_output_key_hash().

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://lore.kernel.org/r/57de760565cab55df7b129f523530ac6475865b2.1712754146.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-11 19:52:11 -07:00
Jon Maloy
05ea491641 tcp: add support for SO_PEEK_OFF socket option
When reading received messages from a socket with MSG_PEEK, we may want
to read the contents with an offset, like we can do with pread/preadv()
when reading files. Currently, it is not possible to do that.

In this commit, we add support for the SO_PEEK_OFF socket option for TCP,
in a similar way it is done for Unix Domain sockets.

In the iperf3 log examples shown below, we can observe a throughput
improvement of 15-20 % in the direction host->namespace when using the
protocol splicer 'pasta' (https://passt.top).
This is a consistent result.

pasta(1) and passt(1) implement user-mode networking for network
namespaces (containers) and virtual machines by means of a translation
layer between Layer-2 network interface and native Layer-4 sockets
(TCP, UDP, ICMP/ICMPv6 echo).

Received, pending TCP data to the container/guest is kept in kernel
buffers until acknowledged, so the tool routinely needs to fetch new
data from socket, skipping data that was already sent.

At the moment this is implemented using a dummy buffer passed to
recvmsg(). With this change, we don't need a dummy buffer and the
related buffer copy (copy_to_user()) anymore.

passt and pasta are supported in KubeVirt and libvirt/qemu.

jmaloy@freyr:~/passt$ perf record -g ./pasta --config-net -f
SO_PEEK_OFF not supported by kernel.

jmaloy@freyr:~/passt# iperf3 -s
-----------------------------------------------------------
Server listening on 5201 (test #1)
-----------------------------------------------------------
Accepted connection from 192.168.122.1, port 44822
[  5] local 192.168.122.180 port 5201 connected to 192.168.122.1 port 44832
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-1.00   sec  1.02 GBytes  8.78 Gbits/sec
[  5]   1.00-2.00   sec  1.06 GBytes  9.08 Gbits/sec
[  5]   2.00-3.00   sec  1.07 GBytes  9.15 Gbits/sec
[  5]   3.00-4.00   sec  1.10 GBytes  9.46 Gbits/sec
[  5]   4.00-5.00   sec  1.03 GBytes  8.85 Gbits/sec
[  5]   5.00-6.00   sec  1.10 GBytes  9.44 Gbits/sec
[  5]   6.00-7.00   sec  1.11 GBytes  9.56 Gbits/sec
[  5]   7.00-8.00   sec  1.07 GBytes  9.20 Gbits/sec
[  5]   8.00-9.00   sec   667 MBytes  5.59 Gbits/sec
[  5]   9.00-10.00  sec  1.03 GBytes  8.83 Gbits/sec
[  5]  10.00-10.04  sec  30.1 MBytes  6.36 Gbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-10.04  sec  10.3 GBytes  8.78 Gbits/sec   receiver
-----------------------------------------------------------
Server listening on 5201 (test #2)
-----------------------------------------------------------
^Ciperf3: interrupt - the server has terminated
jmaloy@freyr:~/passt#
logout
[ perf record: Woken up 23 times to write data ]
[ perf record: Captured and wrote 5.696 MB perf.data (35580 samples) ]
jmaloy@freyr:~/passt$

jmaloy@freyr:~/passt$ perf record -g ./pasta --config-net -f
SO_PEEK_OFF supported by kernel.

jmaloy@freyr:~/passt# iperf3 -s
-----------------------------------------------------------
Server listening on 5201 (test #1)
-----------------------------------------------------------
Accepted connection from 192.168.122.1, port 52084
[  5] local 192.168.122.180 port 5201 connected to 192.168.122.1 port 52098
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-1.00   sec  1.32 GBytes  11.3 Gbits/sec
[  5]   1.00-2.00   sec  1.19 GBytes  10.2 Gbits/sec
[  5]   2.00-3.00   sec  1.26 GBytes  10.8 Gbits/sec
[  5]   3.00-4.00   sec  1.36 GBytes  11.7 Gbits/sec
[  5]   4.00-5.00   sec  1.33 GBytes  11.4 Gbits/sec
[  5]   5.00-6.00   sec  1.21 GBytes  10.4 Gbits/sec
[  5]   6.00-7.00   sec  1.31 GBytes  11.2 Gbits/sec
[  5]   7.00-8.00   sec  1.25 GBytes  10.7 Gbits/sec
[  5]   8.00-9.00   sec  1.33 GBytes  11.5 Gbits/sec
[  5]   9.00-10.00  sec  1.24 GBytes  10.7 Gbits/sec
[  5]  10.00-10.04  sec  56.0 MBytes  12.1 Gbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval           Transfer     Bitrate
[  5]   0.00-10.04  sec  12.9 GBytes  11.0 Gbits/sec  receiver
-----------------------------------------------------------
Server listening on 5201 (test #2)
-----------------------------------------------------------
^Ciperf3: interrupt - the server has terminated
logout
[ perf record: Woken up 20 times to write data ]
[ perf record: Captured and wrote 5.040 MB perf.data (33411 samples) ]
jmaloy@freyr:~/passt$

The perf record confirms this result. Below, we can observe that the
CPU spends significantly less time in the function ____sys_recvmsg()
when we have offset support.

Without offset support:
----------------------
jmaloy@freyr:~/passt$ perf report -q --symbol-filter=do_syscall_64 \
                       -p ____sys_recvmsg -x --stdio -i  perf.data | head -1
46.32%     0.00%  passt.avx2  [kernel.vmlinux]  [k] do_syscall_64  ____sys_recvmsg

With offset support:
----------------------
jmaloy@freyr:~/passt$ perf report -q --symbol-filter=do_syscall_64 \
                       -p ____sys_recvmsg -x --stdio -i  perf.data | head -1
28.12%     0.00%  passt.avx2  [kernel.vmlinux]  [k] do_syscall_64  ____sys_recvmsg

Suggested-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240409152805.913891-1-jmaloy@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-11 19:46:55 -07:00
Mina Almasry
f6d827b180 net: move skb ref helpers to new header
Add a new header, linux/skbuff_ref.h, which contains all the skb_*_ref()
helpers. Many of the consumers of skbuff.h do not actually use any of
the skb ref helpers, and we can speed up compilation a bit by minimizing
this header file.

Additionally in the later patch in the series we add page_pool support
to skb_frag_ref(), which requires some page_pool dependencies. We can
now add these dependencies to skbuff_ref.h instead of a very ubiquitous
skbuff.h

Signed-off-by: Mina Almasry <almasrymina@google.com>
Link: https://lore.kernel.org/r/20240410190505.1225848-2-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-11 19:29:22 -07:00
Jakub Kicinski
94426ed213 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

net/unix/garbage.c
  47d8ac011f ("af_unix: Fix garbage collector racing against connect()")
  4090fa373f ("af_unix: Replace garbage collection algorithm.")

Adjacent changes:

drivers/net/ethernet/broadcom/bnxt/bnxt.c
  faa12ca245 ("bnxt_en: Reset PTP tx_avail after possible firmware reset")
  b3d0083caf ("bnxt_en: Support RSS contexts in ethtool .{get|set}_rxfh()")

drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c
  7ac10c7d72 ("bnxt_en: Fix possible memory leak in bnxt_rdma_aux_device_init()")
  194fad5b27 ("bnxt_en: Refactor bnxt_rdma_aux_device_init/uninit functions")

drivers/net/ethernet/mellanox/mlx5/core/en_ethtool.c
  958f56e483 ("net/mlx5e: Un-expose functions in en.h")
  49e6c93870 ("net/mlx5e: RSS, Block XOR hash with over 128 channels")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-11 14:23:47 -07:00
Eric Dumazet
65acf6e050 netfilter: complete validation of user input
In my recent commit, I missed that do_replace() handlers
use copy_from_sockptr() (which I fixed), followed
by unsafe copy_from_sockptr_offset() calls.

In all functions, we can perform the @optlen validation
before even calling xt_alloc_table_info() with the following
check:

if ((u64)optlen < (u64)tmp.size + sizeof(tmp))
        return -EINVAL;

Fixes: 0c83842df4 ("netfilter: validate user input for expected length")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Pablo Neira Ayuso <pablo@netfilter.org>
Link: https://lore.kernel.org/r/20240409120741.3538135-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-10 19:42:56 -07:00
Eric Dumazet
9b9fd45869 tcp: tweak tcp_sock_write_txrx size assertion
I forgot 32bit arches might have 64bit alignment for u64
fields.

tcp_sock_write_txrx group does not contain pointers,
but two u64 fields. It is possible that on 32bit kernel,
a 32bit hole is before tp->tcp_clock_cache.

I will try to remember a group can be bigger on 32bit
kernels in the future.

With help from Vladimir Oltean.

Fixes: d2c3a7eb1a ("tcp: more struct tcp_sock adjustments")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202404082207.HCEdQhUO-lkp@intel.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20240409140914.4105429-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-10 18:55:05 -07:00
Mina Almasry
959fa5c188 net: make napi_frag_unref reuse skb_page_unref
The implementations of these 2 functions are almost identical. Remove
the implementation of napi_frag_unref, and make it a call into
skb_page_unref so we don't duplicate the implementation.

Signed-off-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Link: https://lore.kernel.org/r/20240408153000.2152844-2-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-09 18:20:29 -07:00
Arnd Bergmann
cf1b7201df ipv4/route: avoid unused-but-set-variable warning
The log_martians variable is only used in an #ifdef, causing a 'make W=1'
warning with gcc:

net/ipv4/route.c: In function 'ip_rt_send_redirect':
net/ipv4/route.c:880:13: error: variable 'log_martians' set but not used [-Werror=unused-but-set-variable]

Change the #ifdef to an equivalent IS_ENABLED() to let the compiler
see where the variable is used.

Fixes: 30038fc61a ("net: ip_rt_send_redirect() optimization")
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240408074219.3030256-2-arnd@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-04-09 15:49:19 +02:00
Eric Dumazet
41eecbd712 tcp: replace TCP_SKB_CB(skb)->tcp_tw_isn with a per-cpu field
TCP can transform a TIMEWAIT socket into a SYN_RECV one from
a SYN packet, and the ISN of the SYNACK packet is normally
generated using TIMEWAIT tw_snd_nxt :

tcp_timewait_state_process()
...
    u32 isn = tcptw->tw_snd_nxt + 65535 + 2;
    if (isn == 0)
        isn++;
    TCP_SKB_CB(skb)->tcp_tw_isn = isn;
    return TCP_TW_SYN;

This SYN packet also bypasses normal checks against listen queue
being full or not.

tcp_conn_request()
...
       __u32 isn = TCP_SKB_CB(skb)->tcp_tw_isn;
...
        /* TW buckets are converted to open requests without
         * limitations, they conserve resources and peer is
         * evidently real one.
         */
        if ((syncookies == 2 || inet_csk_reqsk_queue_is_full(sk)) && !isn) {
                want_cookie = tcp_syn_flood_action(sk, rsk_ops->slab_name);
                if (!want_cookie)
                        goto drop;
        }

This was using TCP_SKB_CB(skb)->tcp_tw_isn field in skb.

Unfortunately this field has been accidentally cleared
after the call to tcp_timewait_state_process() returning
TCP_TW_SYN.

Using a field in TCP_SKB_CB(skb) for a temporary state
is overkill.

Switch instead to a per-cpu variable.

As a bonus, we do not have to clear tcp_tw_isn in TCP receive
fast path.
It is temporarily set then cleared only in the TCP_TW_SYN dance.

Fixes: 4ad19de877 ("net: tcp6: fix double call of tcp_v6_fill_cb()")
Fixes: eeea10b83a ("tcp: add tcp_v4_fill_cb()/tcp_v4_restore_cb()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-04-09 11:47:40 +02:00
Eric Dumazet
b9e8104058 tcp: propagate tcp_tw_isn via an extra parameter to ->route_req()
tcp_v6_init_req() reads TCP_SKB_CB(skb)->tcp_tw_isn to find
out if the request socket is created by a SYN hitting a TIMEWAIT socket.

This has been buggy for a decade, lets directly pass the information
from tcp_conn_request().

This is a preparatory patch to make the following one easier to review.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-04-09 11:47:40 +02:00
Guillaume Nault
ec20b28300 ipv4: Set scope explicitly in ip_route_output().
Add a "scope" parameter to ip_route_output() so that callers don't have
to override the tos parameter with the RTO_ONLINK flag if they want a
local scope.

This will allow converting flowi4_tos to dscp_t in the future, thus
allowing static analysers to flag invalid interactions between
"tos" (the DSCP bits) and ECN.

Only three users ask for local scope (bonding, arp and atm). The others
continue to use RT_SCOPE_UNIVERSE. While there, add a comment to warn
users about the limitations of ip_route_output().

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Acked-by: Leon Romanovsky <leonro@nvidia.com> # infiniband
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-08 13:20:51 +01:00
Eric Dumazet
d2c3a7eb1a tcp: more struct tcp_sock adjustments
tp->recvmsg_inq is used from tcp recvmsg() thus should
be in tcp_sock_read_rx group.

tp->tcp_clock_cache and tp->tcp_mstamp are written
both in rx and tx paths, thus are better placed
in tcp_sock_write_txrx group.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-08 11:49:02 +01:00
Alexander Lobakin
5a66cda52d ip_tunnel: harden copying IP tunnel params to userspace
Structures which are about to be copied to userspace shouldn't have
uninitialized fields or paddings.
memset() the whole &ip_tunnel_parm in ip_tunnel_parm_to_user() before
filling it with the kernel data. The compilers will hopefully combine
writes to it.

Fixes: 117aef12a7 ("ip_tunnel: use a separate struct to store tunnel params in the kernel")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/netdev/5f63dd25-de94-4ca3-84e6-14095953db13@moroto.mountain
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-08 11:02:00 +01:00
Eric Dumazet
802e12ff9c inet: frags: delay fqdir_free_fn()
fqdir_free_fn() is using very expensive rcu_barrier()

When one netns is dismantled, we often call fqdir_exit()
multiple times, typically lauching fqdir_free_fn() twice.

Delaying by one second fqdir_free_fn() helps to reduce
the number of rcu_barrier() calls, and lock contention
on rcu_state.barrier_mutex.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-08 10:59:56 +01:00
Jakub Kicinski
9f06f87fef net: skbuff: generalize the skb->decrypted bit
The ->decrypted bit can be reused for other crypto protocols.
Remove the direct dependency on TLS, add helpers to clean up
the ifdefs leaking out everywhere.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-06 17:34:31 +01:00
Eric Dumazet
f410cbea9f tcp: annotate data-races around tp->window_clamp
tp->window_clamp can be read locklessly, add READ_ONCE()
and WRITE_ONCE() annotations.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Jason Xing <kerneljasonxing@gmail.com>
Link: https://lore.kernel.org/r/20240404114231.2195171-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-05 22:32:37 -07:00
Jakub Kicinski
cf1ca1f66d Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Cross-merge networking fixes after downstream PR.

Conflicts:

net/ipv4/ip_gre.c
  17af420545 ("erspan: make sure erspan_base_hdr is present in skb->head")
  5832c4a77d ("ip_tunnel: convert __be16 tunnel flags to bitmaps")
https://lore.kernel.org/all/20240402103253.3b54a1cf@canb.auug.org.au/

Adjacent changes:

net/ipv6/ip6_fib.c
  d21d40605b ("ipv6: Fix infinite recursion in fib6_dump_done().")
  5fc68320c1 ("ipv6: remove RTNL protection from inet6_dump_fib()")

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-04 18:01:07 -07:00
Eric Dumazet
0c83842df4 netfilter: validate user input for expected length
I got multiple syzbot reports showing old bugs exposed
by BPF after commit 20f2505fb4 ("bpf: Try to avoid kzalloc
in cgroup/{s,g}etsockopt")

setsockopt() @optlen argument should be taken into account
before copying data.

 BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
 BUG: KASAN: slab-out-of-bounds in copy_from_sockptr include/linux/sockptr.h:55 [inline]
 BUG: KASAN: slab-out-of-bounds in do_replace net/ipv4/netfilter/ip_tables.c:1111 [inline]
 BUG: KASAN: slab-out-of-bounds in do_ipt_set_ctl+0x902/0x3dd0 net/ipv4/netfilter/ip_tables.c:1627
Read of size 96 at addr ffff88802cd73da0 by task syz-executor.4/7238

CPU: 1 PID: 7238 Comm: syz-executor.4 Not tainted 6.9.0-rc2-next-20240403-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
  __dump_stack lib/dump_stack.c:88 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
  print_address_description mm/kasan/report.c:377 [inline]
  print_report+0x169/0x550 mm/kasan/report.c:488
  kasan_report+0x143/0x180 mm/kasan/report.c:601
  kasan_check_range+0x282/0x290 mm/kasan/generic.c:189
  __asan_memcpy+0x29/0x70 mm/kasan/shadow.c:105
  copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
  copy_from_sockptr include/linux/sockptr.h:55 [inline]
  do_replace net/ipv4/netfilter/ip_tables.c:1111 [inline]
  do_ipt_set_ctl+0x902/0x3dd0 net/ipv4/netfilter/ip_tables.c:1627
  nf_setsockopt+0x295/0x2c0 net/netfilter/nf_sockopt.c:101
  do_sock_setsockopt+0x3af/0x720 net/socket.c:2311
  __sys_setsockopt+0x1ae/0x250 net/socket.c:2334
  __do_sys_setsockopt net/socket.c:2343 [inline]
  __se_sys_setsockopt net/socket.c:2340 [inline]
  __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x72/0x7a
RIP: 0033:0x7fd22067dde9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fd21f9ff0c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007fd2207abf80 RCX: 00007fd22067dde9
RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fd2206ca47a R08: 0000000000000001 R09: 0000000000000000
R10: 0000000020000880 R11: 0000000000000246 R12: 0000000000000000
R13: 000000000000000b R14: 00007fd2207abf80 R15: 00007ffd2d0170d8
 </TASK>

Allocated by task 7238:
  kasan_save_stack mm/kasan/common.c:47 [inline]
  kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
  poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
  __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
  kasan_kmalloc include/linux/kasan.h:211 [inline]
  __do_kmalloc_node mm/slub.c:4069 [inline]
  __kmalloc_noprof+0x200/0x410 mm/slub.c:4082
  kmalloc_noprof include/linux/slab.h:664 [inline]
  __cgroup_bpf_run_filter_setsockopt+0xd47/0x1050 kernel/bpf/cgroup.c:1869
  do_sock_setsockopt+0x6b4/0x720 net/socket.c:2293
  __sys_setsockopt+0x1ae/0x250 net/socket.c:2334
  __do_sys_setsockopt net/socket.c:2343 [inline]
  __se_sys_setsockopt net/socket.c:2340 [inline]
  __x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x72/0x7a

The buggy address belongs to the object at ffff88802cd73da0
 which belongs to the cache kmalloc-8 of size 8
The buggy address is located 0 bytes inside of
 allocated 1-byte region [ffff88802cd73da0, ffff88802cd73da1)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802cd73020 pfn:0x2cd73
flags: 0xfff80000000000(node=0|zone=1|lastcpupid=0xfff)
page_type: 0xffffefff(slab)
raw: 00fff80000000000 ffff888015041280 dead000000000100 dead000000000122
raw: ffff88802cd73020 000000008080007f 00000001ffffefff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 5103, tgid 2119833701 (syz-executor.4), ts 5103, free_ts 70804600828
  set_page_owner include/linux/page_owner.h:32 [inline]
  post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1490
  prep_new_page mm/page_alloc.c:1498 [inline]
  get_page_from_freelist+0x2e7e/0x2f40 mm/page_alloc.c:3454
  __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4712
  __alloc_pages_node_noprof include/linux/gfp.h:244 [inline]
  alloc_pages_node_noprof include/linux/gfp.h:271 [inline]
  alloc_slab_page+0x5f/0x120 mm/slub.c:2249
  allocate_slab+0x5a/0x2e0 mm/slub.c:2412
  new_slab mm/slub.c:2465 [inline]
  ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3615
  __slab_alloc+0x58/0xa0 mm/slub.c:3705
  __slab_alloc_node mm/slub.c:3758 [inline]
  slab_alloc_node mm/slub.c:3936 [inline]
  __do_kmalloc_node mm/slub.c:4068 [inline]
  kmalloc_node_track_caller_noprof+0x286/0x450 mm/slub.c:4089
  kstrdup+0x3a/0x80 mm/util.c:62
  device_rename+0xb5/0x1b0 drivers/base/core.c:4558
  dev_change_name+0x275/0x860 net/core/dev.c:1232
  do_setlink+0xa4b/0x41f0 net/core/rtnetlink.c:2864
  __rtnl_newlink net/core/rtnetlink.c:3680 [inline]
  rtnl_newlink+0x180b/0x20a0 net/core/rtnetlink.c:3727
  rtnetlink_rcv_msg+0x89b/0x10d0 net/core/rtnetlink.c:6594
  netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2559
  netlink_unicast_kernel net/netlink/af_netlink.c:1335 [inline]
  netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1361
page last free pid 5146 tgid 5146 stack trace:
  reset_page_owner include/linux/page_owner.h:25 [inline]
  free_pages_prepare mm/page_alloc.c:1110 [inline]
  free_unref_page+0xd3c/0xec0 mm/page_alloc.c:2617
  discard_slab mm/slub.c:2511 [inline]
  __put_partials+0xeb/0x130 mm/slub.c:2980
  put_cpu_partial+0x17c/0x250 mm/slub.c:3055
  __slab_free+0x2ea/0x3d0 mm/slub.c:4254
  qlink_free mm/kasan/quarantine.c:163 [inline]
  qlist_free_all+0x9e/0x140 mm/kasan/quarantine.c:179
  kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
  __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:322
  kasan_slab_alloc include/linux/kasan.h:201 [inline]
  slab_post_alloc_hook mm/slub.c:3888 [inline]
  slab_alloc_node mm/slub.c:3948 [inline]
  __do_kmalloc_node mm/slub.c:4068 [inline]
  __kmalloc_node_noprof+0x1d7/0x450 mm/slub.c:4076
  kmalloc_node_noprof include/linux/slab.h:681 [inline]
  kvmalloc_node_noprof+0x72/0x190 mm/util.c:634
  bucket_table_alloc lib/rhashtable.c:186 [inline]
  rhashtable_rehash_alloc+0x9e/0x290 lib/rhashtable.c:367
  rht_deferred_worker+0x4e1/0x2440 lib/rhashtable.c:427
  process_one_work kernel/workqueue.c:3218 [inline]
  process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3299
  worker_thread+0x86d/0xd70 kernel/workqueue.c:3380
  kthread+0x2f0/0x390 kernel/kthread.c:388
  ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
  ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243

Memory state around the buggy address:
 ffff88802cd73c80: 07 fc fc fc 05 fc fc fc 05 fc fc fc fa fc fc fc
 ffff88802cd73d00: fa fc fc fc fa fc fc fc fa fc fc fc fa fc fc fc
>ffff88802cd73d80: fa fc fc fc 01 fc fc fc fa fc fc fc fa fc fc fc
                               ^
 ffff88802cd73e00: fa fc fc fc fa fc fc fc 05 fc fc fc 07 fc fc fc
 ffff88802cd73e80: 07 fc fc fc 07 fc fc fc 07 fc fc fc 07 fc fc fc

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Pablo Neira Ayuso <pablo@netfilter.org>
Link: https://lore.kernel.org/r/20240404122051.2303764-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-04 09:39:52 -07:00
Jason Xing
19822a980e trace: tcp: fully support trace_tcp_send_reset
Prior to this patch, what we can see by enabling trace_tcp_send is
only happening under two circumstances:
1) active rst mode
2) non-active rst mode and based on the full socket

That means the inconsistency occurs if we use tcpdump and trace
simultaneously to see how rst happens.

It's necessary that we should take into other cases into considerations,
say:
1) time-wait socket
2) no socket
...

By parsing the incoming skb and reversing its 4-tuple can
we know the exact 'flow' which might not exist.

Samples after applied this patch:
1. tcp_send_reset: skbaddr=XXX skaddr=XXX src=ip:port dest=ip:port
state=TCP_ESTABLISHED
2. tcp_send_reset: skbaddr=000...000 skaddr=XXX src=ip:port dest=ip:port
state=UNKNOWN
Note:
1) UNKNOWN means we cannot extract the right information from skb.
2) skbaddr/skaddr could be 0

Signed-off-by: Jason Xing <kernelxing@tencent.com>
Link: https://lore.kernel.org/r/20240401073605.37335-3-kerneljasonxing@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-03 19:26:14 -07:00
Alexander Lobakin
4a96a4e807 page_pool: check for PP direct cache locality later
Since we have pool->p.napi (Jakub) and pool->cpuid (Lorenzo) to check
whether it's safe to use direct recycling, we can use both globally for
each page instead of relying solely on @allow_direct argument.
Let's assume that @allow_direct means "I'm sure it's local, don't waste
time rechecking this" and when it's false, try the mentioned params to
still recycle the page directly. If neither is true, we'll lose some
CPU cycles, but then it surely won't be hotpath. On the other hand,
paths where it's possible to use direct cache, but not possible to
safely set @allow_direct, will benefit from this move.
The whole propagation of @napi_safe through a dozen of skb freeing
functions can now go away, which saves us some stack space.

Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Link: https://lore.kernel.org/r/20240329165507.3240110-2-aleksander.lobakin@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-02 18:13:49 -07:00
Eric Dumazet
1eeb504357 tcp/dccp: do not care about families in inet_twsk_purge()
We lost ability to unload ipv6 module a long time ago.

Instead of calling expensive inet_twsk_purge() twice,
we can handle all families in one round.

Also remove an extra line added in my prior patch,
per Kuniyuki Iwashima feedback.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/netdev/20240327192934.6843-1-kuniyu@amazon.com/
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240329153203.345203-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-01 21:27:58 -07:00
Eric Dumazet
58169ec9c4 inet: preserve const qualifier in inet_csk()
We can change inet_csk() to propagate its argument const qualifier,
thanks to container_of_const().

We have to fix few places that had mistakes, like tcp_bound_rto().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240329144931.295800-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-04-01 21:27:08 -07:00
Alexander Lobakin
5832c4a77d ip_tunnel: convert __be16 tunnel flags to bitmaps
Historically, tunnel flags like TUNNEL_CSUM or TUNNEL_ERSPAN_OPT
have been defined as __be16. Now all of those 16 bits are occupied
and there's no more free space for new flags.
It can't be simply switched to a bigger container with no
adjustments to the values, since it's an explicit Endian storage,
and on LE systems (__be16)0x0001 equals to
(__be64)0x0001000000000000.
We could probably define new 64-bit flags depending on the
Endianness, i.e. (__be64)0x0001 on BE and (__be64)0x00010000... on
LE, but that would introduce an Endianness dependency and spawn a
ton of Sparse warnings. To mitigate them, all of those places which
were adjusted with this change would be touched anyway, so why not
define stuff properly if there's no choice.

Define IP_TUNNEL_*_BIT counterparts as a bit number instead of the
value already coded and a fistful of <16 <-> bitmap> converters and
helpers. The two flags which have a different bit position are
SIT_ISATAP_BIT and VTI_ISVTI_BIT, as they were defined not as
__cpu_to_be16(), but as (__force __be16), i.e. had different
positions on LE and BE. Now they both have strongly defined places.
Change all __be16 fields which were used to store those flags, to
IP_TUNNEL_DECLARE_FLAGS() -> DECLARE_BITMAP(__IP_TUNNEL_FLAG_NUM) ->
unsigned long[1] for now, and replace all TUNNEL_* occurrences to
their bitmap counterparts. Use the converters in the places which talk
to the userspace, hardware (NFP) or other hosts (GRE header). The rest
must explicitly use the new flags only. This must be done at once,
otherwise there will be too many conversions throughout the code in
the intermediate commits.
Finally, disable the old __be16 flags for use in the kernel code
(except for the two 'irregular' flags mentioned above), to prevent
any accidental (mis)use of them. For the userspace, nothing is
changed, only additions were made.

Most noticeable bloat-o-meter difference (.text):

vmlinux:	307/-1 (306)
gre.ko:		62/0 (62)
ip_gre.ko:	941/-217 (724)	[*]
ip_tunnel.ko:	390/-900 (-510)	[**]
ip_vti.ko:	138/0 (138)
ip6_gre.ko:	534/-18 (516)	[*]
ip6_tunnel.ko:	118/-10 (108)

[*] gre_flags_to_tnl_flags() grew, but still is inlined
[**] ip_tunnel_find() got uninlined, hence such decrease

The average code size increase in non-extreme case is 100-200 bytes
per module, mostly due to sizeof(long) > sizeof(__be16), as
%__IP_TUNNEL_FLAG_NUM is less than %BITS_PER_LONG and the compilers
are able to expand the majority of bitmap_*() calls here into direct
operations on scalars.

Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-01 10:49:28 +01:00
Alexander Lobakin
117aef12a7 ip_tunnel: use a separate struct to store tunnel params in the kernel
Unlike IPv6 tunnels which use purely-kernel __ip6_tnl_parm structure
to store params inside the kernel, IPv4 tunnel code uses the same
ip_tunnel_parm which is being used to talk with the userspace.
This makes it difficult to alter or add any fields or use a
different format for whatever data.
Define struct ip_tunnel_parm_kern, a 1:1 copy of ip_tunnel_parm for
now, and use it throughout the code. Define the pieces, where the copy
user <-> kernel happens, as standalone functions, and copy the data
there field-by-field, so that the kernel-side structure could be easily
modified later on and the users wouldn't have to care about this.

Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-01 10:49:28 +01:00
Eric Dumazet
1abe267f17 net: add sk_wake_async_rcu() helper
While looking at UDP receive performance, I saw sk_wake_async()
was no longer inlined.

This matters at least on AMD Zen1-4 platforms (see SRSO)

This might be because rcu_read_lock() and rcu_read_unlock()
are no longer nops in recent kernels ?

Add sk_wake_async_rcu() variant, which must be called from
contexts already holding rcu lock.

As SOCK_FASYNC is deprecated in modern days, use unlikely()
to give a hint to the compiler.

sk_wake_async_rcu() is properly inlined from
__udp_enqueue_schedule_skb() and sock_def_readable().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240328144032.1864988-5-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-29 15:03:11 -07:00
Eric Dumazet
612b1c0dec udp: avoid calling sock_def_readable() if possible
sock_def_readable() is quite expensive (particularly
when ep_poll_callback() is in the picture).

We must call sk->sk_data_ready() when :

- receive queue was empty, or
- SO_PEEK_OFF is enabled on the socket, or
- sk->sk_data_ready is not sock_def_readable.

We still need to call sk_wake_async().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240328144032.1864988-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-03-29 15:03:11 -07:00