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BUG: KCSAN: data-race in queue_access_lock / snd_seq_check_queue

read to 0xffff8880b1b21ea4 of 1 bytes by interrupt on cpu 0:
 snd_seq_check_queue+0x59/0x200 sound/core/seq/seq_queue.c:247
 snd_seq_timer_interrupt+0x243/0x280 sound/core/seq/seq_timer.c:158
 snd_timer_process_callbacks+0x1e4/0x220 sound/core/timer.c:757
 snd_timer_interrupt sound/core/timer.c:880 [inline]
 snd_timer_interrupt+0x483/0x930 sound/core/timer.c:801
 snd_hrtimer_callback+0x18f/0x260 sound/core/hrtimer.c:50
 __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
 __tsan_read4+0x1b/0x100 kernel/kcsan/core.c:595
 get_next_corpse net/netfilter/nf_conntrack_core.c:2003 [inline]
 nf_ct_iterate_cleanup+0xe9/0x2e0 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
 rtnl_delete_link+0x98/0xd0 net/core/rtnetlink.c:2836
 rtnl_dellink+0x21a/0x650 net/core/rtnetlink.c:2891
 rtnetlink_rcv_msg+0x1d3/0x500 net/core/rtnetlink.c:5245
 netlink_rcv_skb+0xb0/0x260 net/netlink/af_netlink.c:2477
 rtnetlink_rcv+0x26/0x30 net/core/rtnetlink.c:5263
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0x354/0x430 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x456/0x770 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:637 [inline]
 sock_sendmsg+0x9f/0xc0 net/socket.c:657
 ___sys_sendmsg+0x59d/0x5d0 net/socket.c:2311
 __sys_sendmsg+0xa0/0x160 net/socket.c:2356
 __do_sys_sendmsg net/socket.c:2365 [inline]
 __se_sys_sendmsg net/socket.c:2363 [inline]
 __x64_sys_sendmsg+0x51/0x70 net/socket.c:2363
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8880b1b21ea4 of 1 bytes by task 7951 on cpu 1:
 queue_access_lock+0x89/0xc0 sound/core/seq/seq_queue.c:356
 snd_seq_control_queue+0x77/0x350 sound/core/seq/seq_queue.c:719
 event_input_timer+0x2f/0x50 sound/core/seq/seq_system.c:103
 snd_seq_deliver_single_event.constprop.0+0x3e8/0x4d0 sound/core/seq/seq_clientmgr.c:638
 snd_seq_deliver_event+0x2e9/0x4c0 sound/core/seq/seq_clientmgr.c:839
 snd_seq_dispatch_event+0xa1/0x340 sound/core/seq/seq_clientmgr.c:913
 snd_seq_check_queue+0xeb/0x200 sound/core/seq/seq_queue.c:262
 snd_seq_enqueue_event+0x163/0x2b0 sound/core/seq/seq_queue.c:330
 snd_seq_client_enqueue_event.constprop.0+0x187/0x2a0 sound/core/seq/seq_clientmgr.c:974
 snd_seq_write+0x23f/0x4d0 sound/core/seq/seq_clientmgr.c:1093
 __vfs_write+0x67/0xc0 fs/read_write.c:494
 vfs_write fs/read_write.c:558 [inline]
 vfs_write+0x18a/0x390 fs/read_write.c:542
 ksys_write+0x17b/0x1b0 fs/read_write.c:611
 __do_sys_write fs/read_write.c:623 [inline]
 __se_sys_write fs/read_write.c:620 [inline]
 __x64_sys_write+0x4c/0x60 fs/read_write.c:620
 do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 7951 Comm: syz-executor.5 Not tainted 5.4.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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