syzbot


KCSAN: data-race in pipe_poll / pipe_release (12)

Status: moderation: reported on 2025/11/24 01:31
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+7949d8bc2ada64fe2e40@syzkaller.appspotmail.com
First crash: 4d23h, last: 4d23h
Similar bugs (11)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in pipe_poll / pipe_release (5) fs 6 1 576d 576d 0/29 auto-obsoleted due to no activity on 2024/06/05 09:41
upstream KCSAN: data-race in pipe_poll / pipe_release (10) fs 6 4 197d 219d 0/29 auto-obsoleted due to no activity on 2025/07/10 18:23
upstream KCSAN: data-race in pipe_poll / pipe_release (11) fs 6 4 66d 141d 0/29 auto-obsoleted due to no activity on 2025/11/18 14:55
upstream KCSAN: data-race in pipe_poll / pipe_release (2) fs 6 1 1809d 1809d 0/29 auto-closed as invalid on 2021/01/19 18:58
upstream KCSAN: data-race in pipe_poll / pipe_release (6) fs 6 1 505d 505d 0/29 auto-obsoleted due to no activity on 2024/08/15 20:31
upstream KCSAN: data-race in pipe_poll / pipe_release (9) fs 6 2 302d 303d 0/29 auto-obsoleted due to no activity on 2025/03/27 08:52
upstream KCSAN: data-race in pipe_poll / pipe_release (3) fs 6 1 1372d 1372d 0/29 auto-closed as invalid on 2022/04/01 01:04
upstream KCSAN: data-race in pipe_poll / pipe_release (4) fs 6 1 632d 632d 0/29 auto-obsoleted due to no activity on 2024/04/10 23:01
upstream KCSAN: data-race in pipe_poll / pipe_release fs 6 3 2139d 2205d 0/29 auto-closed as invalid on 2020/03/30 06:30
upstream KCSAN: data-race in pipe_poll / pipe_release (7) fs 6 1 470d 469d 0/29 auto-obsoleted due to no activity on 2024/09/20 00:08
upstream KCSAN: data-race in pipe_poll / pipe_release (8) fs 6 2 398d 425d 0/29 auto-obsoleted due to no activity on 2024/12/21 16:47

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

read-write to 0xffff8881609948a4 of 4 bytes by task 10024 on cpu 1:
 pipe_release+0x6e/0x1d0 fs/pipe.c:731
 __fput+0x29b/0x650 fs/file_table.c:468
 ____fput+0x1c/0x30 fs/file_table.c:496
 task_work_run+0x131/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xed/0x110 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff8881609948a4 of 4 bytes by task 18582 on cpu 0:
 pipe_poll+0x215/0x250 fs/pipe.c:702
 vfs_poll include/linux/poll.h:82 [inline]
 aio_poll_complete_work+0xd4/0x350 fs/aio.c:1733
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3346
 worker_thread+0x582/0x770 kernel/workqueue.c:3427
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x122/0x1b0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00000001 -> 0x00000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 18582 Comm: kworker/0:1 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue: events aio_poll_complete_work
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/24 01:30 upstream d0e88704d96c 4fb8ef37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in pipe_poll / pipe_release
* Struck through repros no longer work on HEAD.