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BUG: KCSAN: data-race in fasync_remove_entry / kill_fasync

write to 0xffff8880b9e72700 of 8 bytes by task 9742 on cpu 1:
 fasync_remove_entry+0xb7/0x120 fs/fcntl.c:882
 fasync_helper+0xc9/0xd6 fs/fcntl.c:981
 perf_fasync+0x64/0x90 kernel/events/core.c:6011
 __fput+0x448/0x4f0 fs/file_table.c:277
 ____fput+0x1b/0x30 fs/file_table.c:313
 task_work_run+0xf5/0x130 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x2ae/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+0x36e/0x390 arch/x86/entry/common.c:304
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880b9e72700 of 8 bytes by interrupt on cpu 0:
 kill_fasync+0x3c/0x170 fs/fcntl.c:1019
 perf_event_wakeup+0x115/0x160 kernel/events/core.c:6051
 perf_pending_event+0x129/0x170 kernel/events/core.c:6107
 irq_work_run_list+0x13e/0x190 kernel/irq_work.c:156
 irq_work_run+0x43/0x90 kernel/irq_work.c:172
 smp_irq_work_interrupt+0x3b/0xf0 arch/x86/kernel/irq_work.c:21
 irq_work_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:860
 __sanitizer_cov_trace_const_cmp1+0x0/0x20 kernel/kcov.c:254
 nf_conntrack_lock+0x5e/0xd0 net/netfilter/nf_conntrack_core.c:96
 get_next_corpse net/netfilter/nf_conntrack_core.c:2001 [inline]
 nf_ct_iterate_cleanup+0xde/0x2e0 net/netfilter/nf_conntrack_core.c:2035
 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2120 [inline]
 nf_ct_iterate_cleanup_net+0xe2/0xf0 net/netfilter/nf_conntrack_core.c:2105
 masq_device_event+0x84/0xa0 net/netfilter/nf_nat_masquerade.c:88
 notifier_call_chain+0xda/0x160 kernel/notifier.c:83
 __raw_notifier_call_chain kernel/notifier.c:361 [inline]
 raw_notifier_call_chain+0x33/0x50 kernel/notifier.c:368
 call_netdevice_notifiers_info net/core/dev.c:1943 [inline]
 call_netdevice_notifiers_info+0x96/0x110 net/core/dev.c:1928
 call_netdevice_notifiers_extack net/core/dev.c:1955 [inline]
 call_netdevice_notifiers net/core/dev.c:1969 [inline]
 dev_close_many+0x251/0x390 net/core/dev.c:1544
 dev_close.part.0+0xcd/0x160 net/core/dev.c:1566
 dev_close+0x4f/0x60 net/core/dev.c:1569
 team_port_add drivers/net/team/team.c:1301 [inline]
 team_add_slave+0x948/0xcd0 drivers/net/team/team.c:1962
 do_set_master net/core/rtnetlink.c:2468 [inline]
 do_set_master+0x15c/0x180 net/core/rtnetlink.c:2441
 do_setlink+0x670/0x1ec0 net/core/rtnetlink.c:2603
 rtnl_setlink+0x19f/0x280 net/core/rtnetlink.c:2882
 rtnetlink_rcv_msg+0x1d0/0x4e0 net/core/rtnetlink.c:5438
 netlink_rcv_skb+0xaf/0x260 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x22/0x30 net/core/rtnetlink.c:5456
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x390/0x4c0 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x4cf/0x8a0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg+0x98/0xc0 net/socket.c:672
 ____sys_sendmsg+0x493/0x4c0 net/socket.c:2343
 ___sys_sendmsg+0xb5/0x100 net/socket.c:2397
 __sys_sendmsg+0x9b/0x150 net/socket.c:2430
 __do_sys_sendmsg net/socket.c:2439 [inline]
 __se_sys_sendmsg net/socket.c:2437 [inline]
 __x64_sys_sendmsg+0x4c/0x60 net/socket.c:2437
 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 9743 Comm: syz-executor.5 Not tainted 5.6.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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