KCSAN: data-race in __stop_tty / do_con_write (4)

Status: auto-obsoleted due to no activity on 2022/10/28 19:26
Subsystems: serial
[Documentation on labels]
First crash: 1418d, last: 1418d
▶ ▼ Similar bugs (9)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __stop_tty / do_con_write (2) serial 6 1 1740d 1740d 0/29 auto-closed as invalid on 2021/12/10 00:27
upstream KCSAN: data-race in __stop_tty / do_con_write (3) serial 6 2 1594d 1597d 0/29 auto-closed as invalid on 2022/05/05 09:26
upstream KCSAN: data-race in __stop_tty / do_con_write serial 6 3 1812d 1851d 0/29 auto-closed as invalid on 2021/09/28 23:33
upstream KCSAN: data-race in __stop_tty / do_con_write (9) serial 6 2 874d 896d 0/29 auto-obsoleted due to no activity on 2024/04/23 21:59
upstream KCSAN: data-race in __stop_tty / do_con_write (10) serial race:benign prio:low 6 2 21d 21d 0/29 moderation: reported on 2026/07/21 04:57
upstream KCSAN: data-race in __stop_tty / do_con_write (8) serial 6 5 1010d 975d 0/29 auto-obsoleted due to no activity on 2023/12/24 00:05
upstream KCSAN: data-race in __stop_tty / do_con_write (5) serial 6 1 1366d 1366d 0/29 auto-obsoleted due to no activity on 2022/12/19 02:12
upstream KCSAN: data-race in __stop_tty / do_con_write (7) serial 6 7 1153d 1166d 0/29 auto-obsoleted due to no activity on 2023/07/20 09:58
upstream KCSAN: data-race in __stop_tty / do_con_write (6) kernel 6 1 1281d 1281d 0/29 auto-obsoleted due to no activity on 2023/04/04 15:34

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

write to 0xffff88813800adbc of 1 bytes by task 17783 on cpu 1:
 __stop_tty+0x3e/0x80 drivers/tty/tty_io.c:760
 n_tty_ioctl_helper+0x2bd/0x340 drivers/tty/tty_ioctl.c:874
 n_tty_ioctl+0xfc/0x1f0 drivers/tty/n_tty.c:2483
 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+0x63/0xcd

read to 0xffff88813800adbc of 1 bytes by task 17782 on cpu 0:
 do_con_write+0x1785/0x3590 drivers/tty/vt/vt.c:2931
 con_write+0x25/0x420 drivers/tty/vt/vt.c:3295
 process_output_block drivers/tty/n_tty.c:586 [inline]
 n_tty_write+0x809/0xb10 drivers/tty/n_tty.c:2350
 do_tty_write drivers/tty/tty_io.c:1024 [inline]
 file_tty_write+0x3f9/0x650 drivers/tty/tty_io.c:1095
 tty_write+0x24/0x30 drivers/tty/tty_io.c:1116
 call_write_iter include/linux/fs.h:2187 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x468/0x760 fs/read_write.c:578
 ksys_write+0xe8/0x1a0 fs/read_write.c:631
 __do_sys_write fs/read_write.c:643 [inline]
 __se_sys_write fs/read_write.c:640 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:640
 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+0x63/0xcd

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 17782 Comm: syz-executor.3 Not tainted 6.0.0-rc6-syzkaller-00210-gbf682942cd26-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/09/23 19:16 upstream bf682942cd26 0042f2b4 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __stop_tty / do_con_write
* Struck through repros no longer work on HEAD.