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BUG: KCSAN: data-race in __neigh_event_send / neigh_resolve_output

write to 0xffff888135363c84 of 1 bytes by interrupt on cpu 1:
 __neigh_event_send+0x458/0xbc0 net/core/neighbour.c:1158
 neigh_event_send_probe include/net/neighbour.h:473 [inline]
 neigh_event_send include/net/neighbour.h:479 [inline]
 neigh_resolve_output+0x110/0x430 net/core/neighbour.c:1512
 neigh_output include/net/neighbour.h:549 [inline]
 ip_finish_output2+0x74b/0x850 net/ipv4/ip_output.c:228
 ip_finish_output+0xf3/0x250 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0xf3/0x1a0 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:451 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0xa2e/0xa50 net/ipv4/ip_output.c:532
 ip_queue_xmit+0x34/0x40 net/ipv4/ip_output.c:546
 __tcp_transmit_skb+0x12a8/0x1790 net/ipv4/tcp_output.c:1403
 tcp_transmit_skb net/ipv4/tcp_output.c:1421 [inline]
 tcp_xmit_probe_skb net/ipv4/tcp_output.c:4010 [inline]
 tcp_write_wakeup+0x47a/0x730 net/ipv4/tcp_output.c:4063
 tcp_send_probe0+0x2c/0x2b0 net/ipv4/tcp_output.c:4078
 tcp_probe_timer net/ipv4/tcp_timer.c:398 [inline]
 tcp_write_timer_handler+0x3eb/0x5d0 net/ipv4/tcp_timer.c:626
 tcp_write_timer+0xb6/0x160 net/ipv4/tcp_timer.c:642
 call_timer_fn+0x2e/0x240 kernel/time/timer.c:1421
 expire_timers+0x116/0x240 kernel/time/timer.c:1466
 __run_timers+0x350/0x400 kernel/time/timer.c:1737
 run_timer_softirq+0x2e/0x60 kernel/time/timer.c:1750
 __do_softirq+0x158/0x2e3 kernel/softirq.c:558
 __irq_exit_rcu kernel/softirq.c:637 [inline]
 irq_exit_rcu+0x41/0x70 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x8d/0xb0 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20
 native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:110 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:551 [inline]
 acpi_idle_enter+0x27b/0x300 drivers/acpi/processor_idle.c:686
 cpuidle_enter_state+0x2ee/0x7a0 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:236 [inline]
 do_idle+0x1b2/0x250 kernel/sched/idle.c:303
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:400
 start_secondary+0x78/0x80 arch/x86/kernel/smpboot.c:266
 secondary_startup_64_no_verify+0xc4/0xcb

read to 0xffff888135363c84 of 1 bytes by interrupt on cpu 0:
 neigh_event_send_probe include/net/neighbour.h:472 [inline]
 neigh_event_send include/net/neighbour.h:479 [inline]
 neigh_resolve_output+0x6f/0x430 net/core/neighbour.c:1512
 neigh_output include/net/neighbour.h:549 [inline]
 ip_finish_output2+0x74b/0x850 net/ipv4/ip_output.c:228
 ip_finish_output+0xf3/0x250 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0xf3/0x1a0 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:451 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0xa2e/0xa50 net/ipv4/ip_output.c:532
 ip_queue_xmit+0x34/0x40 net/ipv4/ip_output.c:546
 __tcp_transmit_skb+0x12a8/0x1790 net/ipv4/tcp_output.c:1403
 tcp_transmit_skb net/ipv4/tcp_output.c:1421 [inline]
 tcp_xmit_probe_skb net/ipv4/tcp_output.c:4010 [inline]
 tcp_write_wakeup+0x47a/0x730 net/ipv4/tcp_output.c:4063
 tcp_send_probe0+0x2c/0x2b0 net/ipv4/tcp_output.c:4078
 tcp_probe_timer net/ipv4/tcp_timer.c:398 [inline]
 tcp_write_timer_handler+0x3eb/0x5d0 net/ipv4/tcp_timer.c:626
 tcp_write_timer+0xb6/0x160 net/ipv4/tcp_timer.c:642
 call_timer_fn+0x2e/0x240 kernel/time/timer.c:1421
 expire_timers+0x116/0x240 kernel/time/timer.c:1466
 __run_timers+0x350/0x400 kernel/time/timer.c:1737
 run_timer_softirq+0x2e/0x60 kernel/time/timer.c:1750
 __do_softirq+0x158/0x2e3 kernel/softirq.c:558
 __irq_exit_rcu kernel/softirq.c:637 [inline]
 irq_exit_rcu+0x41/0x70 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x8d/0xb0 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20
 native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
 acpi_safe_halt drivers/acpi/processor_idle.c:110 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:551 [inline]
 acpi_idle_enter+0x27b/0x300 drivers/acpi/processor_idle.c:686
 cpuidle_enter_state+0x2ee/0x7a0 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:236 [inline]
 do_idle+0x1b2/0x250 kernel/sched/idle.c:303
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:400
 rest_init+0xe8/0xf0 init/main.c:726
 start_kernel+0x0/0x669 init/main.c:882
 start_kernel+0x5e4/0x669 init/main.c:1140
 secondary_startup_64_no_verify+0xc4/0xcb

value changed: 0x20 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.18.0-rc5-syzkaller-00006-g9050ba3a61a4-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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