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KCSAN: data-race in snd_seq_oss_readq_put_timestamp / snd_seq_oss_readq_put_timestamp

Status: auto-closed as invalid on 2020/06/18 13:13
Subsystems: sound
[Documentation on labels]
First crash: 1461d, last: 1461d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in snd_seq_oss_readq_put_timestamp / snd_seq_oss_readq_put_timestamp (3) sound 7 1107d 1194d 0/26 auto-closed as invalid on 2021/05/17 09:01
upstream KCSAN: data-race in snd_seq_oss_readq_put_timestamp / snd_seq_oss_readq_put_timestamp (2) sound 5 1303d 1359d 0/26 auto-closed as invalid on 2020/10/27 20:18

Sample crash report:
==================================================================
BUG: KCSAN: data-race in snd_seq_oss_readq_put_timestamp / snd_seq_oss_readq_put_timestamp

write to 0xffff88809bae5920 of 8 bytes by task 2518 on cpu 1:
 snd_seq_oss_readq_put_timestamp+0xee/0x130 sound/core/seq/oss/seq_oss_readq.c:233
 send_midi_event sound/core/seq/oss/seq_oss_midi.c:600 [inline]
 snd_seq_oss_midi_input+0x108/0x4b0 sound/core/seq/oss/seq_oss_midi.c:524
 snd_seq_oss_event_input+0xf0/0x130 sound/core/seq/oss/seq_oss_event.c:429
 snd_seq_deliver_single_event.constprop.0+0x403/0x500 sound/core/seq/seq_clientmgr.c:638
 deliver_to_subscribers sound/core/seq/seq_clientmgr.c:693 [inline]
 snd_seq_deliver_event+0x1b2/0x4b0 sound/core/seq/seq_clientmgr.c:828
 snd_seq_kernel_client_dispatch+0xe0/0x100 sound/core/seq/seq_clientmgr.c:2323
 snd_vmidi_output_work+0x14d/0x1f0 sound/core/seq/seq_virmidi.c:150
 process_one_work+0x424/0x930 kernel/workqueue.c:2268
 worker_thread+0x9a/0x7e0 kernel/workqueue.c:2414
 kthread+0x203/0x230 kernel/kthread.c:268
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

read to 0xffff88809bae5920 of 8 bytes by task 2517 on cpu 0:
 snd_seq_oss_readq_put_timestamp+0x40/0x130 sound/core/seq/oss/seq_oss_readq.c:218
 send_midi_event sound/core/seq/oss/seq_oss_midi.c:600 [inline]
 snd_seq_oss_midi_input+0x108/0x4b0 sound/core/seq/oss/seq_oss_midi.c:524
 snd_seq_oss_event_input+0xf0/0x130 sound/core/seq/oss/seq_oss_event.c:429
 snd_seq_deliver_single_event.constprop.0+0x403/0x500 sound/core/seq/seq_clientmgr.c:638
 deliver_to_subscribers sound/core/seq/seq_clientmgr.c:693 [inline]
 snd_seq_deliver_event+0x1b2/0x4b0 sound/core/seq/seq_clientmgr.c:828
 snd_seq_kernel_client_dispatch+0xe0/0x100 sound/core/seq/seq_clientmgr.c:2323
 snd_vmidi_output_work+0x14d/0x1f0 sound/core/seq/seq_virmidi.c:150
 process_one_work+0x424/0x930 kernel/workqueue.c:2268
 worker_thread+0x9a/0x7e0 kernel/workqueue.c:2414
 kthread+0x203/0x230 kernel/kthread.c:268
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 2517 Comm: kworker/0:1H Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_highpri snd_vmidi_output_work
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/04/17 17:55 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 18397578 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.