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BUG: KCSAN: data-race in fasync_remove_entry / kill_fasync

write to 0xffff88810316cb00 of 8 bytes by task 23910 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

read to 0xffff88810316cb00 of 8 bytes by interrupt on cpu 0:
 kill_fasync+0x3f/0x180 fs/fcntl.c:1019
 perf_event_wakeup+0x11f/0x160 kernel/events/core.c:6042
 perf_pending_event+0x12d/0x170 kernel/events/core.c:6098
 irq_work_run_list+0x136/0x190 kernel/irq_work.c:156
 irq_work_run+0x48/0xa0 kernel/irq_work.c:172
 smp_irq_work_interrupt+0x3f/0x100 arch/x86/kernel/irq_work.c:21
 irq_work_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:860
 validate_xmit_skb+0x7a0/0x870 net/core/dev.c:3513
 __dev_queue_xmit+0xbce/0x1ba0 net/core/dev.c:4005
 dev_queue_xmit+0x21/0x30 net/core/dev.c:4046
 neigh_hh_output include/net/neighbour.h:500 [inline]
 neigh_output include/net/neighbour.h:509 [inline]
 ip_finish_output2+0x89b/0xea0 net/ipv4/ip_output.c:228
 __ip_finish_output net/ipv4/ip_output.c:308 [inline]
 __ip_finish_output+0x23a/0x490 net/ipv4/ip_output.c:290
 ip_finish_output+0x41/0x160 net/ipv4/ip_output.c:318
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0xfe/0x230 net/ipv4/ip_output.c:432
 dst_output include/net/dst.h:436 [inline]
 ip_local_out+0x74/0x90 net/ipv4/ip_output.c:125
 __ip_queue_xmit+0x3a8/0xa40 net/ipv4/ip_output.c:532
 ip_queue_xmit+0x45/0x60 include/net/ip.h:237
 __tcp_transmit_skb+0xea3/0x1df0 net/ipv4/tcp_output.c:1170
 tcp_transmit_skb net/ipv4/tcp_output.c:1186 [inline]
 tcp_write_xmit+0xa74/0x3190 net/ipv4/tcp_output.c:2441
 __tcp_push_pending_frames+0x7b/0x1d0 net/ipv4/tcp_output.c:2617
 tcp_push_pending_frames include/net/tcp.h:1827 [inline]
 tcp_data_snd_check net/ipv4/tcp_input.c:5217 [inline]
 tcp_rcv_established+0x56a/0xf50 net/ipv4/tcp_input.c:5709
 tcp_v4_do_rcv+0x3b5/0x520 net/ipv4/tcp_ipv4.c:1562
 sk_backlog_rcv include/net/sock.h:949 [inline]
 __release_sock+0x135/0x1e0 net/core/sock.c:2437
 release_sock+0x61/0x160 net/core/sock.c:2953
 tcp_sendpage+0x53/0x70 net/ipv4/tcp.c:1118
 inet_sendpage+0xae/0x100 net/ipv4/af_inet.c:821
 kernel_sendpage+0x7b/0xc0 net/socket.c:3776
 kcm_write_msgs+0x202/0xd30 net/kcm/kcmsock.c:647
 kcm_push net/kcm/kcmsock.c:754 [inline]
 kcm_sendmsg+0x13be/0x1485 net/kcm/kcmsock.c:928
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg+0x9f/0xc0 net/socket.c:659
 ____sys_sendmsg+0x212/0x4d0 net/socket.c:2330
 ___sys_sendmsg+0xb5/0x100 net/socket.c:2384
 __sys_sendmmsg+0x123/0x350 net/socket.c:2474
 __do_sys_sendmmsg net/socket.c:2503 [inline]
 __se_sys_sendmmsg net/socket.c:2500 [inline]
 __x64_sys_sendmmsg+0x64/0x80 net/socket.c:2500
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 23912 Comm: syz-executor.5 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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