================================================================== BUG: KCSAN: data-race in n_tty_receive_buf_common / n_tty_receive_char write to 0xffffc9000052d018 of 8 bytes by task 12344 on cpu 0: echo_char_raw drivers/tty/n_tty.c:841 [inline] eraser drivers/tty/n_tty.c:1082 [inline] n_tty_receive_char_special drivers/tty/n_tty.c:1308 [inline] n_tty_receive_buf_standard drivers/tty/n_tty.c:1558 [inline] __receive_buf drivers/tty/n_tty.c:1577 [inline] n_tty_receive_buf_common+0x221c/0x4e70 drivers/tty/n_tty.c:1674 n_tty_receive_buf+0x2b/0x40 drivers/tty/n_tty.c:1703 tiocsti drivers/tty/tty_io.c:2311 [inline] tty_ioctl+0x968/0x1120 drivers/tty/tty_io.c:2719 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl+0xcb/0x140 fs/ioctl.c:1055 __x64_sys_ioctl+0x3f/0x50 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae read to 0xffffc9000052d018 of 8 bytes by task 7772 on cpu 1: add_echo_byte drivers/tty/n_tty.c:840 [inline] echo_char drivers/tty/n_tty.c:946 [inline] n_tty_receive_char+0x483/0x6c0 drivers/tty/n_tty.c:1410 n_tty_receive_buf_standard drivers/tty/n_tty.c:1560 [inline] __receive_buf drivers/tty/n_tty.c:1577 [inline] n_tty_receive_buf_common+0xf2e/0x4e70 drivers/tty/n_tty.c:1674 n_tty_receive_buf2+0x2e/0x40 drivers/tty/n_tty.c:1709 tty_ldisc_receive_buf+0x5b/0xf0 drivers/tty/tty_buffer.c:471 tty_port_default_receive_buf+0x54/0x80 drivers/tty/tty_port.c:39 receive_buf drivers/tty/tty_buffer.c:491 [inline] flush_to_ldisc+0x1c5/0x2c0 drivers/tty/tty_buffer.c:543 process_one_work+0x3e9/0x8f0 kernel/workqueue.c:2276 worker_thread+0x636/0xae0 kernel/workqueue.c:2422 kthread+0x262/0x280 kernel/kthread.c:319 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 value changed: 0x000000000000064a -> 0x00000000000008da Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 7772 Comm: kworker/u4:11 Not tainted 5.14.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound flush_to_ldisc ==================================================================