syzbot


KCSAN: data-race in snd_rawmidi_read / snd_rawmidi_receive

Status: auto-closed as invalid on 2020/02/24 07:17
Subsystems: sound
[Documentation on labels]
First crash: 1564d, last: 1564d

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

read to 0xffff8880a3c740f8 of 8 bytes by task 16874 on cpu 1:
 snd_rawmidi_read+0x177/0x460 sound/core/rawmidi.c:1023
 __vfs_read+0x67/0xc0 fs/read_write.c:425
 vfs_read fs/read_write.c:461 [inline]
 vfs_read+0x143/0x2c0 fs/read_write.c:446
 ksys_read+0x17b/0x1b0 fs/read_write.c:587
 __do_sys_read fs/read_write.c:597 [inline]
 __se_sys_read fs/read_write.c:595 [inline]
 __x64_sys_read+0x4c/0x60 fs/read_write.c:595
 do_syscall_64+0xcc/0x3a0 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

write to 0xffff8880a3c740f8 of 8 bytes by task 16876 on cpu 0:
 snd_rawmidi_receive+0x1a3/0x4c0 sound/core/rawmidi.c:911
 snd_virmidi_dev_receive_event sound/core/seq/seq_virmidi.c:87 [inline]
 snd_virmidi_event_input sound/core/seq/seq_virmidi.c:109 [inline]
 snd_virmidi_event_input+0x1e3/0x270 sound/core/seq/seq_virmidi.c:101
 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_kernel_client_dispatch+0xef/0x110 sound/core/seq/seq_clientmgr.c:2323
 snd_seq_oss_dispatch sound/core/seq/oss/seq_oss_device.h:138 [inline]
 snd_seq_oss_midi_reset+0x253/0x2e0 sound/core/seq/oss/seq_oss_midi.c:474
 snd_seq_oss_synth_reset+0x2b1/0x4c0 sound/core/seq/oss/seq_oss_synth.c:404
 snd_seq_oss_reset+0x4f/0x170 sound/core/seq/oss/seq_oss_init.c:435
 snd_seq_oss_release+0x6e/0xf0 sound/core/seq/oss/seq_oss_init.c:412
 odev_release+0x49/0x70 sound/core/seq/oss/seq_oss.c:140
 __fput+0x1e1/0x520 fs/file_table.c:280
 ____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

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 16876 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
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/12/16 07:14 https://github.com/google/ktsan.git kcsan 245a43005292 eef6e580 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.