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BUG: KCSAN: data-race in __neigh_event_send / neigh_resolve_output

write to 0xffff8881047d1484 of 1 bytes by interrupt on cpu 0:
 __neigh_event_send+0x458/0xbc0 net/core/neighbour.c:1182
 neigh_event_send_probe include/net/neighbour.h:470 [inline]
 neigh_event_send include/net/neighbour.h:476 [inline]
 neigh_resolve_output+0x110/0x430 net/core/neighbour.c:1536
 neigh_output include/net/neighbour.h:546 [inline]
 ip_finish_output2+0x74d/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:291 [inline]
 ip_output+0xf3/0x1a0 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:445 [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+0x1242/0x1730 net/ipv4/tcp_output.c:1402
 tcp_transmit_skb net/ipv4/tcp_output.c:1420 [inline]
 tcp_xmit_probe_skb net/ipv4/tcp_output.c:4025 [inline]
 tcp_write_wakeup+0x47a/0x730 net/ipv4/tcp_output.c:4078
 tcp_send_probe0+0x2c/0x2b0 net/ipv4/tcp_output.c:4093
 tcp_probe_timer net/ipv4/tcp_timer.c:393 [inline]
 tcp_write_timer_handler+0x324/0x4b0 net/ipv4/tcp_timer.c:624
 tcp_write_timer+0xad/0x150 net/ipv4/tcp_timer.c:637
 call_timer_fn+0x2e/0x240 kernel/time/timer.c:1474
 expire_timers+0x116/0x240 kernel/time/timer.c:1519
 __run_timers+0x350/0x400 kernel/time/timer.c:1790
 run_timer_softirq+0x2e/0x60 kernel/time/timer.c:1803
 __do_softirq+0xf2/0x2c7 kernel/softirq.c:571
 __irq_exit_rcu kernel/softirq.c:650 [inline]
 irq_exit_rcu+0x41/0x70 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x8d/0xb0 arch/x86/kernel/apic/apic.c:1107
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
 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:112 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:572 [inline]
 acpi_idle_enter+0x283/0x340 drivers/acpi/processor_idle.c:709
 cpuidle_enter_state+0x2de/0x960 drivers/cpuidle/cpuidle.c:239
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:356
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:236 [inline]
 do_idle+0x1a7/0x250 kernel/sched/idle.c:303
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:400
 rest_init+0xe8/0xf0 init/main.c:727
 start_kernel+0x0/0x656 init/main.c:883
 start_kernel+0x5d1/0x656 init/main.c:1138
 secondary_startup_64_no_verify+0xcf/0xdb

read to 0xffff8881047d1484 of 1 bytes by interrupt on cpu 1:
 neigh_event_send_probe include/net/neighbour.h:469 [inline]
 neigh_event_send include/net/neighbour.h:476 [inline]
 neigh_resolve_output+0x6f/0x430 net/core/neighbour.c:1536
 neigh_output include/net/neighbour.h:546 [inline]
 ip_finish_output2+0x74d/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:291 [inline]
 ip_output+0xf3/0x1a0 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:445 [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+0x1242/0x1730 net/ipv4/tcp_output.c:1402
 tcp_transmit_skb net/ipv4/tcp_output.c:1420 [inline]
 tcp_xmit_probe_skb net/ipv4/tcp_output.c:4025 [inline]
 tcp_write_wakeup+0x47a/0x730 net/ipv4/tcp_output.c:4078
 tcp_send_probe0+0x2c/0x2b0 net/ipv4/tcp_output.c:4093
 tcp_probe_timer net/ipv4/tcp_timer.c:393 [inline]
 tcp_write_timer_handler+0x324/0x4b0 net/ipv4/tcp_timer.c:624
 tcp_write_timer+0xad/0x150 net/ipv4/tcp_timer.c:637
 call_timer_fn+0x2e/0x240 kernel/time/timer.c:1474
 expire_timers+0x116/0x240 kernel/time/timer.c:1519
 __run_timers+0x350/0x400 kernel/time/timer.c:1790
 run_timer_softirq+0x2e/0x60 kernel/time/timer.c:1803
 __do_softirq+0xf2/0x2c7 kernel/softirq.c:571
 __irq_exit_rcu kernel/softirq.c:650 [inline]
 irq_exit_rcu+0x41/0x70 kernel/softirq.c:662
 sysvec_apic_timer_interrupt+0x8d/0xb0 arch/x86/kernel/apic/apic.c:1107
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:649
 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:112 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:572 [inline]
 acpi_idle_enter+0x283/0x340 drivers/acpi/processor_idle.c:709
 cpuidle_enter_state+0x2de/0x960 drivers/cpuidle/cpuidle.c:239
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:356
 call_cpuidle kernel/sched/idle.c:155 [inline]
 cpuidle_idle_call kernel/sched/idle.c:236 [inline]
 do_idle+0x1a7/0x250 kernel/sched/idle.c:303
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:400
 start_secondary+0x78/0x80 arch/x86/kernel/smpboot.c:262
 secondary_startup_64_no_verify+0xcf/0xdb

value changed: 0x20 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 6.0.0-syzkaller-09039-ga6afa4199d3d-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
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