KCSAN: data-race in snd_seq_oss_readq_clear / snd_seq_oss_readq_put

Kernel	Title	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in snd_seq_oss_readq_clear / snd_seq_oss_readq_put_event (2) sound				2	1271d	1291d	0/26	auto-closed as invalid on 2020/12/05 08:21

================================================================== BUG: KCSAN: data-race in snd_seq_oss_readq_clear / snd_seq_oss_readq_put_event write to 0xffff888073c19388 of 4 bytes by task 22776 on cpu 1: snd_seq_oss_readq_clear+0x35/0x90 sound/core/seq/oss/seq_oss_readq.c:77 snd_seq_oss_reset+0x102/0x160 sound/core/seq/oss/seq_oss_init.c:445 snd_seq_oss_release+0x76/0x170 sound/core/seq/oss/seq_oss_init.c:412 odev_release+0x3a/0x60 sound/core/seq/oss/seq_oss.c:140 __fput+0x246/0x4d0 fs/file_table.c:281 ____fput+0x11/0x20 fs/file_table.c:314 task_work_run+0x8e/0x110 kernel/task_work.c:141 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:139 [inline] exit_to_user_mode_prepare+0x1b2/0x210 kernel/entry/common.c:166 syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:241 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffff888073c19388 of 4 bytes by task 6 on cpu 0: snd_seq_oss_readq_put_event+0x38/0x150 sound/core/seq/oss/seq_oss_readq.c:146 send_synth_event sound/core/seq/oss/seq_oss_midi.c:586 [inline] snd_seq_oss_midi_input+0x4ea/0x500 sound/core/seq/oss/seq_oss_midi.c:522 snd_seq_oss_event_input+0xbc/0x100 sound/core/seq/oss/seq_oss_event.c:429 snd_seq_deliver_single_event+0x31b/0x4f0 sound/core/seq/seq_clientmgr.c:638 deliver_to_subscribers sound/core/seq/seq_clientmgr.c:693 [inline] snd_seq_deliver_event+0x392/0x4a0 sound/core/seq/seq_clientmgr.c:828 snd_seq_kernel_client_dispatch+0x16f/0x190 sound/core/seq/seq_clientmgr.c:2323 snd_vmidi_output_work+0x16d/0x200 sound/core/seq/seq_virmidi.c:150 process_one_work+0x3e1/0x9a0 kernel/workqueue.c:2269 worker_thread+0x665/0xbe0 kernel/workqueue.c:2415 kthread+0x20d/0x230 kernel/kthread.c:292 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 6 Comm: kworker/0:0H Not tainted 5.9.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_highpri snd_vmidi_output_work ==================================================================