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KCSAN: data-race in __stop_tty / n_tty_receive_char (2)

Status: auto-closed as invalid on 2022/05/15 01:17
Subsystems: serial
[Documentation on labels]
First crash: 692d, last: 683d
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 (5) serial 4 160d 197d 0/26 auto-obsoleted due to no activity on 2023/10/20 07:37
upstream KCSAN: data-race in __stop_tty / n_tty_receive_char (6) serial 4 4d08h 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 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 0xffff8881314af1bc of 1 bytes by task 25915 on cpu 1:
 __stop_tty+0x3e/0x80 drivers/tty/tty_io.c:760
 n_tty_ioctl_helper+0x2bd/0x340 drivers/tty/tty_ioctl.c:872
 n_tty_ioctl+0xfc/0x1f0 drivers/tty/n_tty.c:2381
 tty_ioctl+0x71e/0x970 drivers/tty/tty_io.c:2787
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:856
 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881314af1bc of 1 bytes by task 44 on cpu 0:
 n_tty_receive_char+0x3b/0x6a0 drivers/tty/n_tty.c:1373
 n_tty_receive_buf_standard drivers/tty/n_tty.c:1532 [inline]
 __receive_buf drivers/tty/n_tty.c:1549 [inline]
 n_tty_receive_buf_common+0xef3/0x4c40 drivers/tty/n_tty.c:1645
 n_tty_receive_buf2+0x2e/0x40 drivers/tty/n_tty.c:1680
 tty_ldisc_receive_buf+0x5b/0xf0 drivers/tty/tty_buffer.c:451
 tty_port_default_receive_buf+0x54/0x80 drivers/tty/tty_port.c:39
 receive_buf drivers/tty/tty_buffer.c:471 [inline]
 flush_to_ldisc+0x1ca/0x2f0 drivers/tty/tty_buffer.c:521
 process_one_work+0x3d3/0x720 kernel/workqueue.c:2289
 worker_thread+0x618/0xa70 kernel/workqueue.c:2436
 kthread+0x1a9/0x1e0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 44 Comm: kworker/u4:2 Not tainted 5.18.0-rc1-syzkaller-00328-ge1f700ebd6be-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events_unbound flush_to_ldisc
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/04/10 01:14 upstream e1f700ebd6be e22c3da3 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __stop_tty / n_tty_receive_char
2022/04/01 18:14 upstream d0d642a5d365 79a2a8fc .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __stop_tty / n_tty_receive_char
* Struck through repros no longer work on HEAD.