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BUG: KCSAN: data-race in icmp_global_allow / icmp_global_allow

write to 0xffffffff861a4a54 of 4 bytes by interrupt on cpu 1:
 icmp_global_allow+0x174/0x1b0 net/ipv4/icmp.c:272
 icmpv4_global_allow net/ipv4/icmp.c:299 [inline]
 icmpv4_global_allow+0x83/0xc0 net/ipv4/icmp.c:294
 __icmp_send+0x925/0xaa0 net/ipv4/icmp.c:664
 ipv4_send_dest_unreach net/ipv4/route.c:1220 [inline]
 ipv4_link_failure+0x22d/0x400 net/ipv4/route.c:1227
 dst_link_failure include/net/dst.h:419 [inline]
 arp_error_report+0x72/0x90 net/ipv4/arp.c:293
 neigh_invalidate+0x1b2/0x320 net/core/neighbour.c:996
 neigh_timer_handler+0x7cb/0x870 net/core/neighbour.c:1082
 call_timer_fn+0x5f/0x2f0 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0xc0c/0xcd0 kernel/time/timer.c:1786
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:373 [inline]
 irq_exit+0xbb/0xe0 kernel/softirq.c:413
 exiting_irq arch/x86/include/asm/apic.h:536 [inline]
 smp_apic_timer_interrupt+0xe6/0x280 arch/x86/kernel/apic/apic.c:1137
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:830
 native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:60
 arch_cpu_idle+0xa/0x10 arch/x86/kernel/process.c:571
 default_idle_call+0x1e/0x40 kernel/sched/idle.c:94
 cpuidle_idle_call kernel/sched/idle.c:154 [inline]
 do_idle+0x1af/0x280 kernel/sched/idle.c:263
 cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:355
 start_secondary+0x168/0x1b0 arch/x86/kernel/smpboot.c:264
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

read to 0xffffffff861a4a54 of 4 bytes by interrupt on cpu 0:
 icmp_global_allow+0x36/0x1b0 net/ipv4/icmp.c:254
 icmpv4_global_allow net/ipv4/icmp.c:299 [inline]
 icmpv4_global_allow+0x83/0xc0 net/ipv4/icmp.c:294
 __icmp_send+0x925/0xaa0 net/ipv4/icmp.c:664
 ipv4_send_dest_unreach net/ipv4/route.c:1220 [inline]
 ipv4_link_failure+0x22d/0x400 net/ipv4/route.c:1227
 dst_link_failure include/net/dst.h:419 [inline]
 arp_error_report+0x72/0x90 net/ipv4/arp.c:293
 neigh_invalidate+0x1b2/0x320 net/core/neighbour.c:996
 neigh_timer_handler+0x7cb/0x870 net/core/neighbour.c:1082
 call_timer_fn+0x5f/0x2f0 kernel/time/timer.c:1404
 expire_timers kernel/time/timer.c:1449 [inline]
 __run_timers kernel/time/timer.c:1773 [inline]
 __run_timers kernel/time/timer.c:1740 [inline]
 run_timer_softirq+0xc0c/0xcd0 kernel/time/timer.c:1786
 __do_softirq+0x115/0x33f kernel/softirq.c:292
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1082
 do_softirq.part.0+0x6b/0x80 kernel/softirq.c:337
 do_softirq kernel/softirq.c:329 [inline]
 __local_bh_enable_ip+0x76/0x80 kernel/softirq.c:189
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 get_next_corpse net/netfilter/nf_conntrack_core.c:2013 [inline]
 nf_ct_iterate_cleanup+0x129/0x2e0 net/netfilter/nf_conntrack_core.c:2036
 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2121 [inline]
 nf_ct_iterate_cleanup_net+0xe2/0xf0 net/netfilter/nf_conntrack_core.c:2106
 masq_device_event+0x8a/0x90 net/netfilter/nf_nat_masquerade.c:88
 notifier_call_chain+0xd7/0x160 kernel/notifier.c:95
 __raw_notifier_call_chain kernel/notifier.c:396 [inline]
 raw_notifier_call_chain+0x37/0x50 kernel/notifier.c:403
 call_netdevice_notifiers_info+0x48/0xc0 net/core/dev.c:1668
 call_netdevice_notifiers_extack net/core/dev.c:1680 [inline]
 call_netdevice_notifiers net/core/dev.c:1694 [inline]
 dev_close_many+0x264/0x3a0 net/core/dev.c:1437
 rollback_registered_many+0x2fb/0xa00 net/core/dev.c:8499
 unregister_netdevice_many net/core/dev.c:9675 [inline]
 unregister_netdevice_many+0x62/0x240 net/core/dev.c:9670
 default_device_exit_batch+0x234/0x270 net/core/dev.c:10146
 ops_exit_list.isra.0+0xa2/0xc0 net/core/net_namespace.c:175
 cleanup_net+0x405/0x6b0 net/core/net_namespace.c:597
 process_one_work+0x3d4/0x890 kernel/workqueue.c:2269
 worker_thread+0xa0/0x800 kernel/workqueue.c:2415
 kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 28 Comm: kworker/u4:3 Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
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