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

Status: auto-obsoleted due to no activity on 2022/11/10 02:34
Subsystems: serial
[Documentation on labels]
First crash: 509d, last: 504d
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 (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 0xffff88813c0d55bc of 1 bytes by task 13054 on cpu 0:
 __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 0xffff88813c0d55bc of 1 bytes by task 1995 on cpu 1:
 n_tty_receive_char+0x3b/0x6a0 drivers/tty/n_tty.c:1410
 n_tty_receive_buf_standard+0x3b3/0x3a30 drivers/tty/n_tty.c:1589
 __receive_buf drivers/tty/n_tty.c:1613 [inline]
 n_tty_receive_buf_common+0x72d/0xbf0 drivers/tty/n_tty.c:1711
 n_tty_receive_buf2+0x2e/0x40 drivers/tty/n_tty.c:1746
 tty_ldisc_receive_buf+0x5b/0xf0 drivers/tty/tty_buffer.c:457
 tty_port_default_receive_buf+0x54/0x80 drivers/tty/tty_port.c:39
 receive_buf drivers/tty/tty_buffer.c:515 [inline]
 flush_to_ldisc+0x1d9/0x470 drivers/tty/tty_buffer.c:565
 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 arch/x86/entry/entry_64.S:306

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 1995 Comm: kworker/u4:7 Not tainted 6.0.0-syzkaller-03015-g2bca25eaeba6-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022
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
2022/10/06 02:31 upstream 2bca25eaeba6 2c6543ad .config console log report info [disk image] [vmlinux] ci2-upstream-kcsan-gce KCSAN: data-race in __stop_tty / n_tty_receive_char
2022/09/30 19:51 upstream 70575e77839f feb56351 .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.