syzbot


KCSAN: data-race in io_sq_thread / io_sq_thread_park (9)

Status: fixed on 2024/10/03 15:25
Subsystems: io-uring
[Documentation on labels]
Reported-by: syzbot+2b946a3fd80caf971b21@syzkaller.appspotmail.com
Fix commit: e4956dc7a84d io_uring/sqpoll: annotate debug task == current with data_race()
First crash: 127d, last: 127d
Discussions (2)
Title Replies (including bot) Last reply
[syzbot] [io-uring?] KCSAN: data-race in io_sq_thread / io_sq_thread_park (9) 2 (4) 2024/08/13 12:17
[PATCH] io_uring/sqpoll: annotate debug task == current with data_race() 1 (1) 2024/08/13 12:16
Similar bugs (8)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in io_sq_thread / io_sq_thread_park (5) io-uring 1 593d 593d 0/28 auto-obsoleted due to no activity on 2023/06/04 19:25
upstream KCSAN: data-race in io_sq_thread / io_sq_thread_park fs 13 922d 1089d 0/28 auto-closed as invalid on 2022/07/10 14:43
upstream KCSAN: data-race in io_sq_thread / io_sq_thread_park (4) io-uring 4 645d 687d 0/28 auto-obsoleted due to no activity on 2023/04/20 22:18
upstream KCSAN: data-race in io_sq_thread / io_sq_thread_park (8) io-uring 2 308d 334d 0/28 auto-obsoleted due to no activity on 2024/03/15 14:43
upstream KCSAN: data-race in io_sq_thread / io_sq_thread_park (2) io-uring 5 850d 886d 0/28 auto-closed as invalid on 2022/09/20 09:21
upstream KCSAN: data-race in io_sq_thread / io_sq_thread_park (6) io-uring 4 494d 540d 0/28 auto-obsoleted due to no activity on 2023/09/11 04:02
upstream KCSAN: data-race in io_sq_thread / io_sq_thread_park (7) io-uring 2 386d 368d 0/28 auto-obsoleted due to no activity on 2023/12/28 08:55
upstream KCSAN: data-race in io_sq_thread / io_sq_thread_park (3) io-uring 2 783d 810d 0/28 auto-obsoleted due to no activity on 2022/11/26 22:35

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

write to 0xffff888111459638 of 8 bytes by task 10761 on cpu 1:
 io_sq_thread+0xdab/0xff0 io_uring/sqpoll.c:383
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

read to 0xffff888111459638 of 8 bytes by task 10329 on cpu 0:
 io_sq_thread_park+0x1b/0x80 io_uring/sqpoll.c:47
 io_ring_exit_work+0x197/0x500 io_uring/io_uring.c:2786
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3312
 worker_thread+0x526/0x700 kernel/workqueue.c:3390
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0xffff8881223d0000 -> 0x0000000000000000

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 10329 Comm: kworker/u8:8 Not tainted 6.11.0-rc2-syzkaller-00027-g6a0e38264012 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: iou_exit io_ring_exit_work
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/08/08 16:34 upstream 6a0e38264012 61405512 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in io_sq_thread / io_sq_thread_park
* Struck through repros no longer work on HEAD.