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KCSAN: data-race in snd_rawmidi_kernel_write1 / snd_rawmidi_write (2)

Status: closed as invalid on 2020/06/18 14:24
Subsystems: sound
[Documentation on labels]
First crash: 1445d, last: 1418d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in snd_rawmidi_kernel_write1 / snd_rawmidi_write sound 16 1517d 1626d 0/26 auto-closed as invalid on 2020/05/09 17:19
upstream KCSAN: data-race in snd_rawmidi_kernel_write1 / snd_rawmidi_write (3) sound 5 1379d 1401d 0/26 auto-closed as invalid on 2020/08/20 11:35

Sample crash report:
==================================================================
BUG: KCSAN: data-race in snd_rawmidi_kernel_write1 / snd_rawmidi_write

write to 0xffff88809c1dd1b8 of 8 bytes by task 24265 on cpu 0:
 snd_rawmidi_kernel_write1+0x1d6/0x420 sound/core/rawmidi.c:1356
 snd_rawmidi_write+0x1bc/0x730 sound/core/rawmidi.c:1429
 __vfs_write+0x58/0xb0 fs/read_write.c:495
 __kernel_write+0xb0/0x230 fs/read_write.c:516
 write_pipe_buf+0xad/0xe0 fs/splice.c:809
 splice_from_pipe_feed fs/splice.c:512 [inline]
 __splice_from_pipe+0x298/0x4a0 fs/splice.c:636
 splice_from_pipe+0xc2/0x100 fs/splice.c:671
 default_file_splice_write+0x41/0x90 fs/splice.c:821
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0x97/0xb0 fs/splice.c:1037
 splice_direct_to_actor+0x22f/0x540 fs/splice.c:992
 do_splice_direct+0x152/0x1d0 fs/splice.c:1080
 do_sendfile+0x380/0x800 fs/read_write.c:1521
 __do_sys_sendfile64 fs/read_write.c:1582 [inline]
 __se_sys_sendfile64 fs/read_write.c:1568 [inline]
 __x64_sys_sendfile64+0x121/0x140 fs/read_write.c:1568
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88809c1dd1b8 of 8 bytes by task 24274 on cpu 1:
 snd_rawmidi_write+0x5c7/0x730 sound/core/rawmidi.c:1424
 __vfs_write+0x58/0xb0 fs/read_write.c:495
 __kernel_write+0xb0/0x230 fs/read_write.c:516
 write_pipe_buf+0xad/0xe0 fs/splice.c:809
 splice_from_pipe_feed fs/splice.c:512 [inline]
 __splice_from_pipe+0x298/0x4a0 fs/splice.c:636
 splice_from_pipe+0xc2/0x100 fs/splice.c:671
 default_file_splice_write+0x41/0x90 fs/splice.c:821
 do_splice_from fs/splice.c:863 [inline]
 direct_splice_actor+0x97/0xb0 fs/splice.c:1037
 splice_direct_to_actor+0x22f/0x540 fs/splice.c:992
 do_splice_direct+0x152/0x1d0 fs/splice.c:1080
 do_sendfile+0x380/0x800 fs/read_write.c:1521
 __do_sys_sendfile64 fs/read_write.c:1582 [inline]
 __se_sys_sendfile64 fs/read_write.c:1568 [inline]
 __x64_sys_sendfile64+0x121/0x140 fs/read_write.c:1568
 do_syscall_64+0xc7/0x3b0 arch/x86/entry/common.c:295
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 24274 Comm: syz-executor.0 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/07 05:29 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 e6b89e4e .config console log report ci2-upstream-kcsan-gce
2020/06/04 13:13 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 6720fdef .config console log report ci2-upstream-kcsan-gce
2020/05/31 08:50 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 a0331e89 .config console log report ci2-upstream-kcsan-gce
2020/05/26 01:28 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 8ca3b7d2 .config console log report ci2-upstream-kcsan-gce
2020/05/11 20:21 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 9eb09c40 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.