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BUG: KCSAN: data-race in __neigh_event_send / neigh_resolve_output

write to 0xffff88812d099a84 of 1 bytes by interrupt on cpu 1:
 __neigh_event_send+0x3bd/0xa70 net/core/neighbour.c:1213
 neigh_event_send_probe include/net/neighbour.h:470 [inline]
 neigh_event_send include/net/neighbour.h:476 [inline]
 neigh_resolve_output+0x114/0x430 net/core/neighbour.c:1567
 neigh_output include/net/neighbour.h:546 [inline]
 ip_finish_output2+0x740/0x840 net/ipv4/ip_output.c:228
 ip_finish_output+0xf4/0x240 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:291 [inline]
 ip_output+0xe5/0x1b0 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:444 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0xa4d/0xa70 net/ipv4/ip_output.c:532
 ip_queue_xmit+0x38/0x40 net/ipv4/ip_output.c:546
 __tcp_transmit_skb+0x1165/0x16c0 net/ipv4/tcp_output.c:1399
 tcp_transmit_skb net/ipv4/tcp_output.c:1417 [inline]
 __tcp_retransmit_skb+0x78d/0xb20 net/ipv4/tcp_output.c:3241
 tcp_retransmit_skb+0x26/0x140 net/ipv4/tcp_output.c:3264
 tcp_retransmit_timer+0x10f5/0x15e0 net/ipv4/tcp_timer.c:537
 tcp_write_timer_handler+0x258/0x500 net/ipv4/tcp_timer.c:620
 tcp_write_timer+0x8b/0x160 net/ipv4/tcp_timer.c:637
 call_timer_fn+0x35/0x290 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x46c/0x650 kernel/time/timer.c:2022
 run_timer_softirq+0x32/0x60 kernel/time/timer.c:2035
 __do_softirq+0xe4/0x2b0 kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x85/0x100 kernel/softirq.c:650
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1107
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline]
 acpi_safe_halt+0x20/0x30 drivers/acpi/processor_idle.c:112
 acpi_idle_do_entry+0x19/0x30 drivers/acpi/processor_idle.c:573
 acpi_idle_enter+0xbe/0xe0 drivers/acpi/processor_idle.c:711
 cpuidle_enter_state+0xc6/0x260 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x40/0x60 drivers/cpuidle/cpuidle.c:388
 call_cpuidle kernel/sched/idle.c:134 [inline]
 cpuidle_idle_call kernel/sched/idle.c:215 [inline]
 do_idle+0x1a3/0x250 kernel/sched/idle.c:282
 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379
 start_secondary+0x7c/0x80 arch/x86/kernel/smpboot.c:264
 secondary_startup_64_no_verify+0xcf/0xdb

read to 0xffff88812d099a84 of 1 bytes by interrupt on cpu 0:
 neigh_event_send_probe include/net/neighbour.h:469 [inline]
 neigh_event_send include/net/neighbour.h:476 [inline]
 neigh_resolve_output+0x73/0x430 net/core/neighbour.c:1567
 neigh_output include/net/neighbour.h:546 [inline]
 ip_finish_output2+0x740/0x840 net/ipv4/ip_output.c:228
 ip_finish_output+0xf4/0x240 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:291 [inline]
 ip_output+0xe5/0x1b0 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:444 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0xa4d/0xa70 net/ipv4/ip_output.c:532
 ip_queue_xmit+0x38/0x40 net/ipv4/ip_output.c:546
 __tcp_transmit_skb+0x1165/0x16c0 net/ipv4/tcp_output.c:1399
 tcp_transmit_skb net/ipv4/tcp_output.c:1417 [inline]
 __tcp_retransmit_skb+0x78d/0xb20 net/ipv4/tcp_output.c:3241
 tcp_retransmit_skb+0x26/0x140 net/ipv4/tcp_output.c:3264
 tcp_retransmit_timer+0x10f5/0x15e0 net/ipv4/tcp_timer.c:537
 tcp_write_timer_handler+0x258/0x500 net/ipv4/tcp_timer.c:620
 tcp_write_timer+0x8b/0x160 net/ipv4/tcp_timer.c:637
 call_timer_fn+0x35/0x290 kernel/time/timer.c:1700
 expire_timers kernel/time/timer.c:1751 [inline]
 __run_timers+0x46c/0x650 kernel/time/timer.c:2022
 run_timer_softirq+0x32/0x60 kernel/time/timer.c:2035
 __do_softirq+0xe4/0x2b0 kernel/softirq.c:571
 invoke_softirq kernel/softirq.c:445 [inline]
 __irq_exit_rcu+0x85/0x100 kernel/softirq.c:650
 sysvec_apic_timer_interrupt+0x91/0xb0 arch/x86/kernel/apic/apic.c:1107
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:645
 native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline]
 arch_safe_halt arch/x86/include/asm/irqflags.h:86 [inline]
 acpi_safe_halt+0x20/0x30 drivers/acpi/processor_idle.c:112
 acpi_idle_do_entry+0x19/0x30 drivers/acpi/processor_idle.c:573
 acpi_idle_enter+0xbe/0xe0 drivers/acpi/processor_idle.c:711
 cpuidle_enter_state+0xc6/0x260 drivers/cpuidle/cpuidle.c:267
 cpuidle_enter+0x40/0x60 drivers/cpuidle/cpuidle.c:388
 call_cpuidle kernel/sched/idle.c:134 [inline]
 cpuidle_idle_call kernel/sched/idle.c:215 [inline]
 do_idle+0x1a3/0x250 kernel/sched/idle.c:282
 cpu_startup_entry+0x18/0x20 kernel/sched/idle.c:379
 rest_init+0xef/0xf0 init/main.c:732
 arch_call_rest_init+0x9/0x10 init/main.c:894
 start_kernel+0x58a/0x610 init/main.c:1148
 secondary_startup_64_no_verify+0xcf/0xdb

value changed: 0x20 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.3.0-rc3-syzkaller-00021-ga1effab7a3a3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
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