==================================================================
BUG: KCSAN: data-race in do_con_write / stop_tty

write to 0xffff888137d855bc of 1 bytes by task 5882 on cpu 1:
 __stop_tty drivers/tty/tty_io.c:760 [inline]
 stop_tty+0x54/0xb0 drivers/tty/tty_io.c:784
 n_tty_receive_char_flow_ctrl drivers/tty/n_tty.c:1241 [inline]
 n_tty_receive_char_special drivers/tty/n_tty.c:1249 [inline]
 n_tty_receive_buf_standard drivers/tty/n_tty.c:1543 [inline]
 __receive_buf drivers/tty/n_tty.c:1562 [inline]
 n_tty_receive_buf_common+0x10fd/0x4c40 drivers/tty/n_tty.c:1658
 n_tty_receive_buf2+0x2e/0x40 drivers/tty/n_tty.c:1693
 tty_ldisc_receive_buf+0x5b/0xf0 drivers/tty/tty_buffer.c:452
 tty_port_default_receive_buf+0x54/0x80 drivers/tty/tty_port.c:39
 receive_buf drivers/tty/tty_buffer.c:472 [inline]
 flush_to_ldisc+0x1ca/0x2f0 drivers/tty/tty_buffer.c:522
 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

read to 0xffff888137d855bc of 1 bytes by task 18388 on cpu 0:
 do_con_write+0x1785/0x3590 drivers/tty/vt/vt.c:2931
 con_write+0x25/0x420 drivers/tty/vt/vt.c:3295
 n_tty_write+0x39a/0xb40 drivers/tty/n_tty.c:2320
 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:2186 [inline]
 new_sync_write fs/read_write.c:504 [inline]
 vfs_write+0x71c/0x890 fs/read_write.c:591
 ksys_write+0xe8/0x1a0 fs/read_write.c:644
 __do_sys_write fs/read_write.c:656 [inline]
 __se_sys_write fs/read_write.c:653 [inline]
 __x64_sys_write+0x3e/0x50 fs/read_write.c:653
 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: 18388 Comm: syz-executor.4 Not tainted 5.19.0-syzkaller-00428-g9de1f9c8ca51-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
==================================================================