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BUG: KCSAN: data-race in __perf_event_overflow / fasync_remove_entry

read to 0xffff8880a5d8c700 of 8 bytes by interrupt on cpu 0:
 __perf_event_overflow+0x11d/0x200 kernel/events/core.c:8429
 perf_swevent_hrtimer+0x261/0x280 kernel/events/core.c:9813
 __run_hrtimer kernel/time/hrtimer.c:1517 [inline]
 __hrtimer_run_queues+0x274/0x5f0 kernel/time/hrtimer.c:1579
 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1641
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline]
 smp_apic_timer_interrupt+0xdc/0x280 arch/x86/kernel/apic/apic.c:1135
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829
 nf_conntrack_lock+0x75/0xd0 net/netfilter/nf_conntrack_core.c:110
 get_next_corpse net/netfilter/nf_conntrack_core.c:2000 [inline]
 nf_ct_iterate_cleanup+0xdd/0x2e0 net/netfilter/nf_conntrack_core.c:2034
 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2119 [inline]
 nf_ct_iterate_cleanup_net+0xe2/0xf0 net/netfilter/nf_conntrack_core.c:2104
 masq_inet_event+0xaf/0xc0 net/netfilter/nf_nat_masquerade.c:125
 notifier_call_chain+0xd7/0x160 kernel/notifier.c:83
 __blocking_notifier_call_chain+0x89/0xd0 kernel/notifier.c:284
 blocking_notifier_call_chain+0x37/0x50 kernel/notifier.c:295
 __inet_del_ifa+0x38a/0x6e0 net/ipv4/devinet.c:427
 inet_del_ifa net/ipv4/devinet.c:464 [inline]
 devinet_ioctl+0x881/0xf30 net/ipv4/devinet.c:1159
 inet_ioctl+0x12b/0x240 net/ipv4/af_inet.c:957
 sock_do_ioctl+0x61/0x230 net/socket.c:1040
 sock_ioctl+0x3a3/0x5e0 net/socket.c:1191
 vfs_ioctl fs/ioctl.c:47 [inline]
 file_ioctl fs/ioctl.c:545 [inline]
 do_vfs_ioctl+0x84f/0xcf0 fs/ioctl.c:732
 ksys_ioctl+0xbd/0xe0 fs/ioctl.c:749
 __do_sys_ioctl fs/ioctl.c:756 [inline]
 __se_sys_ioctl fs/ioctl.c:754 [inline]
 __x64_sys_ioctl+0x4c/0x60 fs/ioctl.c:754
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8880a5d8c700 of 8 bytes by task 16934 on cpu 1:
 fasync_remove_entry+0xba/0x120 fs/fcntl.c:882
 fasync_helper+0xcf/0xdc fs/fcntl.c:981
 perf_fasync+0x6c/0xa0 kernel/events/core.c:6002
 __fput+0x46a/0x520 fs/file_table.c:277
 ____fput+0x1f/0x30 fs/file_table.c:313
 task_work_run+0xf6/0x130 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:164
 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:278 [inline]
 do_syscall_64+0x384/0x3a0 arch/x86/entry/common.c:304
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 16934 Comm: syz-executor.3 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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