syzbot


KCSAN: data-race in __stop_tty / n_tty_receive_char (5)

Status: auto-obsoleted due to no activity on 2023/10/20 07:37
Subsystems: serial
[Documentation on labels]
First crash: 197d, last: 160d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __stop_tty / n_tty_receive_char (6) serial 4 4d09h 29d 0/26 moderation: reported on 2024/01/24 17:45
upstream KCSAN: data-race in __stop_tty / n_tty_receive_char (4) serial 2 504d 509d 0/26 auto-obsoleted due to no activity on 2022/11/10 02:34
upstream KCSAN: data-race in __stop_tty / n_tty_receive_char (3) serial 1 593d 593d 0/26 auto-closed as invalid on 2022/08/13 02:09
upstream KCSAN: data-race in __stop_tty / n_tty_receive_char (2) serial 2 683d 692d 0/26 auto-closed as invalid on 2022/05/15 01:17
upstream KCSAN: data-race in __stop_tty / n_tty_receive_char serial 1 878d 878d 0/26 auto-closed as invalid on 2021/11/01 13:40

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __stop_tty / n_tty_receive_char

write to 0xffff888107d1c5bc of 1 bytes by task 12357 on cpu 0:
 __stop_tty+0x42/0x90 drivers/tty/tty_io.c:753
 n_tty_ioctl_helper+0x21f/0x240 drivers/tty/tty_ioctl.c:961
 n_tty_ioctl+0xfd/0x200 drivers/tty/n_tty.c:2516
 tty_ioctl+0x875/0xbc0 drivers/tty/tty_io.c:2785
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:871 [inline]
 __se_sys_ioctl+0xcf/0x140 fs/ioctl.c:857
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:857
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff888107d1c5bc of 1 bytes by task 29202 on cpu 1:
 n_tty_receive_char+0x3d/0x670 drivers/tty/n_tty.c:1432
 n_tty_receive_buf_standard+0x4bd/0x2e20 drivers/tty/n_tty.c:1611
 __receive_buf drivers/tty/n_tty.c:1635 [inline]
 n_tty_receive_buf_common+0x7e5/0xbc0 drivers/tty/n_tty.c:1734
 n_tty_receive_buf2+0x33/0x40 drivers/tty/n_tty.c:1780
 tty_ldisc_receive_buf+0x60/0xe0 drivers/tty/tty_buffer.c:387
 tty_port_default_receive_buf+0x59/0x90 drivers/tty/tty_port.c:37
 receive_buf drivers/tty/tty_buffer.c:445 [inline]
 flush_to_ldisc+0x1ca/0x400 drivers/tty/tty_buffer.c:495
 process_one_work kernel/workqueue.c:2630 [inline]
 process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703
 worker_thread+0x525/0x730 kernel/workqueue.c:2784
 kthread+0x1d7/0x210 kernel/kthread.c:388
 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 29202 Comm: kworker/u4:51 Not tainted 6.6.0-rc1-syzkaller-00115-g9fdfb15a3dbf #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
Workqueue: events_unbound flush_to_ldisc
==================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/09/15 07:35 upstream 9fdfb15a3dbf 0b6a67ac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __stop_tty / n_tty_receive_char
2023/08/13 15:14 upstream a785fd28d31f 39990d51 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __stop_tty / n_tty_receive_char
2023/08/10 09:39 upstream 374a7f47bf40 13ca4cd6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __stop_tty / n_tty_receive_char
2023/08/09 13:56 upstream 13b937206866 8ad1a287 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __stop_tty / n_tty_receive_char
* Struck through repros no longer work on HEAD.