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BUG: KCSAN: data-race in __neigh_event_send / neigh_resolve_output

write to 0xffff888135d5c884 of 1 bytes by interrupt on cpu 1:
 __neigh_event_send+0x409/0xb10 net/core/neighbour.c:1157
 neigh_event_send include/net/neighbour.h:456 [inline]
 neigh_resolve_output+0x104/0x410 net/core/neighbour.c:1506
 neigh_output include/net/neighbour.h:527 [inline]
 ip_finish_output2+0x72e/0xb40 net/ipv4/ip_output.c:221
 ip_finish_output+0xfb/0x240 net/ipv4/ip_output.c:309
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0xf3/0x1a0 net/ipv4/ip_output.c:423
 dst_output include/net/dst.h:450 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0xa1a/0xa40 net/ipv4/ip_output.c:525
 ip_queue_xmit+0x34/0x40 net/ipv4/ip_output.c:539
 __tcp_transmit_skb+0x132a/0x1840 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:3995 [inline]
 tcp_write_wakeup+0x495/0x8d0 net/ipv4/tcp_output.c:4048
 tcp_send_probe0+0x2c/0x2b0 net/ipv4/tcp_output.c:4063
 tcp_probe_timer net/ipv4/tcp_timer.c:398 [inline]
 tcp_write_timer_handler+0x3e9/0x5d0 net/ipv4/tcp_timer.c:626
 tcp_write_timer+0xb9/0x160 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+0x368/0x410 kernel/time/timer.c:1734
 run_timer_softirq+0x2e/0x60 kernel/time/timer.c:1747
 __do_softirq+0x158/0x2de kernel/softirq.c:558
 __irq_exit_rcu kernel/softirq.c:637 [inline]
 irq_exit_rcu+0x37/0x70 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:109 [inline]
 acpi_idle_do_entry drivers/acpi/processor_idle.c:553 [inline]
 acpi_idle_enter+0x282/0x300 drivers/acpi/processor_idle.c:688
 cpuidle_enter_state+0x2b4/0x7d0 drivers/cpuidle/cpuidle.c:237
 cpuidle_enter+0x3c/0x60 drivers/cpuidle/cpuidle.c:351
 call_cpuidle kernel/sched/idle.c:158 [inline]
 cpuidle_idle_call kernel/sched/idle.c:239 [inline]
 do_idle+0x1b2/0x250 kernel/sched/idle.c:306
 cpu_startup_entry+0x15/0x20 kernel/sched/idle.c:403
 secondary_startup_64_no_verify+0xb1/0xbb

read to 0xffff888135d5c884 of 1 bytes by interrupt on cpu 0:
 neigh_event_send include/net/neighbour.h:455 [inline]
 neigh_resolve_output+0x6f/0x410 net/core/neighbour.c:1506
 neigh_output include/net/neighbour.h:527 [inline]
 ip_finish_output2+0x72e/0xb40 net/ipv4/ip_output.c:221
 ip_finish_output+0xfb/0x240 net/ipv4/ip_output.c:309
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0xf3/0x1a0 net/ipv4/ip_output.c:423
 dst_output include/net/dst.h:450 [inline]
 ip_local_out net/ipv4/ip_output.c:126 [inline]
 __ip_queue_xmit+0xa1a/0xa40 net/ipv4/ip_output.c:525
 ip_queue_xmit+0x34/0x40 net/ipv4/ip_output.c:539
 __tcp_transmit_skb+0x132a/0x1840 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:3995 [inline]
 tcp_write_wakeup+0x495/0x8d0 net/ipv4/tcp_output.c:4048
 tcp_send_probe0+0x2c/0x2b0 net/ipv4/tcp_output.c:4063
 tcp_probe_timer net/ipv4/tcp_timer.c:398 [inline]
 tcp_write_timer_handler+0x3e9/0x5d0 net/ipv4/tcp_timer.c:626
 tcp_write_timer+0xb9/0x160 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+0x368/0x410 kernel/time/timer.c:1734
 run_timer_softirq+0x2e/0x60 kernel/time/timer.c:1747
 __do_softirq+0x158/0x2de kernel/softirq.c:558
 __irq_exit_rcu kernel/softirq.c:637 [inline]
 irq_exit_rcu+0x37/0x70 kernel/softirq.c:649
 sysvec_apic_timer_interrupt+0x8d/0xb0 arch/x86/kernel/apic/apic.c:1097
 asm_sysvec_apic_timer_interrupt+0x12/0x20
 finish_task_switch+0xda/0x280 kernel/sched/core.c:4852
 context_switch kernel/sched/core.c:4975 [inline]
 __schedule+0x44a/0x6a0 kernel/sched/core.c:6253
 schedule+0x81/0xb0 kernel/sched/core.c:6326
 freezable_schedule include/linux/freezer.h:172 [inline]
 do_nanosleep+0xcc/0x3a0 kernel/time/hrtimer.c:2044
 hrtimer_nanosleep+0x10b/0x200 kernel/time/hrtimer.c:2097
 common_nsleep+0x69/0x80 kernel/time/posix-timers.c:1227
 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1267 [inline]
 __se_sys_clock_nanosleep+0x1f1/0x220 kernel/time/posix-timers.c:1245
 __x64_sys_clock_nanosleep+0x51/0x60 kernel/time/posix-timers.c:1245
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x20 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 7173 Comm: syz-executor.1 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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