syzbot


KCSAN: data-race in mm_update_next_owner / wb_workfn (8)

Status: auto-closed as invalid on 2021/06/25 06:02
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 462d, last: 452d
similar bugs (7):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in mm_update_next_owner / wb_workfn (4) 1 673d 673d 0/23 auto-closed as invalid on 2020/11/16 07:19
upstream KCSAN: data-race in mm_update_next_owner / wb_workfn (7) 1 521d 521d 0/23 auto-closed as invalid on 2021/04/17 00:26
upstream KCSAN: data-race in mm_update_next_owner / wb_workfn (3) 2 759d 779d 0/23 auto-closed as invalid on 2020/08/22 21:27
upstream KCSAN: data-race in mm_update_next_owner / wb_workfn (5) 2 613d 617d 0/23 auto-closed as invalid on 2021/01/15 21:05
upstream KCSAN: data-race in mm_update_next_owner / wb_workfn (2) 3 869d 959d 0/23 auto-closed as invalid on 2020/06/08 08:14
upstream KCSAN: data-race in mm_update_next_owner / wb_workfn (6) 2 565d 577d 0/23 auto-closed as invalid on 2021/03/04 08:19
upstream KCSAN: data-race in mm_update_next_owner / wb_workfn 2 1012d 1023d 0/23 closed as invalid on 2019/11/19 14:44

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

write to 0xffff8881003f90ac of 4 bytes by task 81 on cpu 0:
 wb_workfn+0x78/0x520 fs/fs-writeback.c:2080
 process_one_work+0x3e9/0x8f0 kernel/workqueue.c:2275
 worker_thread+0x636/0xae0 kernel/workqueue.c:2421
 kthread+0x1d0/0x1f0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

read to 0xffff8881003f90ac of 4 bytes by task 23802 on cpu 1:
 mm_update_next_owner+0x1d9/0x520 kernel/exit.c:389
 exit_mm+0x358/0x450 kernel/exit.c:501
 do_exit+0x3ff/0x1560 kernel/exit.c:813
 do_group_exit+0xce/0x1a0 kernel/exit.c:923
 get_signal+0xfc3/0x1610 kernel/signal.c:2818
 arch_do_signal_or_restart+0x2a/0x220 arch/x86/kernel/signal.c:789
 handle_signal_work kernel/entry/common.c:147 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x109/0x190 kernel/entry/common.c:208
 __syscall_exit_to_user_mode_work kernel/entry/common.c:290 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:301
 do_syscall_64+0x56/0x90 arch/x86/entry/common.c:57
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 23802 Comm: syz-executor.3 Not tainted 5.13.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (4):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2021/05/21 05:56 upstream ba816d3c265c 3c7fef33 .config log report info KCSAN: data-race in mm_update_next_owner / wb_workfn
ci2-upstream-kcsan-gce 2021/05/21 05:37 upstream ba816d3c265c 3c7fef33 .config log report info KCSAN: data-race in mm_update_next_owner / wb_workfn
ci2-upstream-kcsan-gce 2021/05/21 00:02 upstream f01da525b3de 3c7fef33 .config log report info KCSAN: data-race in mm_update_next_owner / wb_workfn
ci2-upstream-kcsan-gce 2021/05/11 02:00 upstream 1140ab592e2e ca873091 .config log report info KCSAN: data-race in mm_update_next_owner / wb_workfn