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BUG: KCSAN: data-race in __perf_event_overflow / fasync_remove_entry

read to 0xffff8880afa48af8 of 8 bytes by interrupt on cpu 0:
 __perf_event_overflow+0x11d/0x200 kernel/events/core.c:8192
 perf_swevent_hrtimer+0x261/0x280 kernel/events/core.c:9576
 __run_hrtimer kernel/time/hrtimer.c:1514 [inline]
 __hrtimer_run_queues+0x274/0x5f0 kernel/time/hrtimer.c:1576
 hrtimer_interrupt+0x22a/0x480 kernel/time/hrtimer.c:1638
 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:830
 __this_cpu_preempt_check+0x8/0x170 lib/smp_processor_id.c:63
 xt_write_recseq_begin include/linux/netfilter/x_tables.h:371 [inline]
 ipt_do_table+0x1bf/0xe60 net/ipv4/netfilter/ip_tables.c:260
 ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:56 [inline]
 iptable_mangle_hook+0x132/0x260 net/ipv4/netfilter/iptable_mangle.c:81
 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline]
 nf_hook_slow+0x83/0x160 net/netfilter/core.c:512
 nf_hook include/linux/netfilter.h:260 [inline]
 __ip_local_out+0x1f7/0x2b0 net/ipv4/ip_output.c:114
 ip_local_out+0x31/0x90 net/ipv4/ip_output.c:123
 __ip_queue_xmit+0x3a8/0xa40 net/ipv4/ip_output.c:532
 ip_queue_xmit+0x45/0x60 include/net/ip.h:237
 __tcp_transmit_skb+0xe81/0x1d60 net/ipv4/tcp_output.c:1169
 tcp_transmit_skb net/ipv4/tcp_output.c:1185 [inline]
 tcp_write_xmit+0xa54/0x3120 net/ipv4/tcp_output.c:2440
 __tcp_push_pending_frames+0x7b/0x1d0 net/ipv4/tcp_output.c:2616
 tcp_push_pending_frames include/net/tcp.h:1810 [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:1564
 sk_backlog_rcv include/net/sock.h:950 [inline]
 __release_sock+0x135/0x1e0 net/core/sock.c:2439
 release_sock+0x61/0x160 net/core/sock.c:2955
 sk_stream_wait_memory+0x454/0x850 net/core/stream.c:145
 tcp_sendmsg_locked+0x962/0x1fb0 net/ipv4/tcp.c:1395
 tcp_sendmsg+0x39/0x60 net/ipv4/tcp.c:1436
 inet_sendmsg+0x6d/0x90 net/ipv4/af_inet.c:807
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg+0x9f/0xc0 net/socket.c:657
 __sys_sendto+0x21f/0x320 net/socket.c:1952
 __do_sys_sendto net/socket.c:1964 [inline]
 __se_sys_sendto net/socket.c:1960 [inline]
 __x64_sys_sendto+0x89/0xb0 net/socket.c:1960
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8880afa48af8 of 8 bytes by task 10628 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:5917
 __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:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x353/0x370 arch/x86/entry/common.c:300
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 10628 Comm: syz-executor.3 Not tainted 5.4.0-rc7+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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