================================================================== BUG: KCSAN: data-race in commit_echoes / n_tty_receive_char_special write to 0xffffc90001575018 of 8 bytes by task 9010 on cpu 1: add_echo_byte drivers/tty/n_tty.c:845 [inline] echo_char_raw drivers/tty/n_tty.c:923 [inline] eraser drivers/tty/n_tty.c:1079 [inline] n_tty_receive_char_special+0x116d/0x1bc0 drivers/tty/n_tty.c:1316 n_tty_receive_buf_fast drivers/tty/n_tty.c:1610 [inline] __receive_buf drivers/tty/n_tty.c:1644 [inline] n_tty_receive_buf_common+0x17d6/0x1a40 drivers/tty/n_tty.c:1742 n_tty_receive_buf+0x36/0x50 drivers/tty/n_tty.c:1771 tiocsti drivers/tty/tty_io.c:2200 [inline] tty_ioctl+0xaf5/0xd80 drivers/tty/tty_io.c:2576 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x101/0x150 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x47/0x60 fs/ioctl.c:770 do_syscall_64+0xc7/0x390 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x44/0xa9 read to 0xffffc90001575018 of 8 bytes by task 135 on cpu 0: commit_echoes+0x51/0x160 drivers/tty/n_tty.c:779 n_tty_receive_char_fast drivers/tty/n_tty.c:1449 [inline] n_tty_receive_buf_fast drivers/tty/n_tty.c:1609 [inline] __receive_buf drivers/tty/n_tty.c:1644 [inline] n_tty_receive_buf_common+0x16dc/0x1a40 drivers/tty/n_tty.c:1742 n_tty_receive_buf2+0x39/0x50 drivers/tty/n_tty.c:1777 tty_ldisc_receive_buf+0x69/0xe0 drivers/tty/tty_buffer.c:461 tty_port_default_receive_buf+0x82/0xd0 drivers/tty/tty_port.c:38 receive_buf drivers/tty/tty_buffer.c:481 [inline] flush_to_ldisc+0x1dd/0x260 drivers/tty/tty_buffer.c:533 process_one_work+0x424/0x930 kernel/workqueue.c:2264 worker_thread+0x9a/0x7e0 kernel/workqueue.c:2410 kthread+0x1cb/0x1f0 kernel/kthread.c:255 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352 Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 135 Comm: kworker/u4:3 Not tainted 5.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events_unbound flush_to_ldisc ==================================================================