================================================================== BUG: KCSAN: data-race in n_tty_receive_buf_common / n_tty_receive_char write to 0xffffc9000e4d1018 of 8 bytes by task 3883 on cpu 0: echo_char_raw drivers/tty/n_tty.c:841 [inline] finish_erasing drivers/tty/n_tty.c:958 [inline] n_tty_receive_char+0x254/0x6c0 drivers/tty/n_tty.c:1406 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 read to 0xffffc9000e4d1018 of 8 bytes by task 12904 on cpu 1: add_echo_byte drivers/tty/n_tty.c:840 [inline] echo_char drivers/tty/n_tty.c:945 [inline] eraser drivers/tty/n_tty.c:1040 [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+0x2131/0x4e70 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 value changed: 0x00000000000035c0 -> 0x00000000000035eb Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 12904 Comm: syz-executor.3 Not tainted 5.14.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ==================================================================