================================================================== BUG: KCSAN: data-race in n_tty_receive_buf_common / n_tty_write write to 0xffffc900006f5020 of 8 bytes by task 10346 on cpu 1: process_echoes drivers/tty/n_tty.c:793 [inline] n_tty_write+0x1b9/0xb60 drivers/tty/n_tty.c:2370 iterate_tty_write drivers/tty/tty_io.c:1017 [inline] file_tty_write+0x398/0x6b0 drivers/tty/tty_io.c:1088 tty_write+0x28/0x30 drivers/tty/tty_io.c:1109 call_write_iter include/linux/fs.h:1956 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x4ab/0x7d0 fs/read_write.c:584 ksys_write+0xeb/0x1a0 fs/read_write.c:637 __do_sys_write fs/read_write.c:649 [inline] __se_sys_write fs/read_write.c:646 [inline] __x64_sys_write+0x42/0x50 fs/read_write.c:646 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd read to 0xffffc900006f5020 of 8 bytes by task 26 on cpu 0: flush_echoes drivers/tty/n_tty.c:807 [inline] __receive_buf drivers/tty/n_tty.c:1637 [inline] n_tty_receive_buf_common+0x87d/0xbc0 drivers/tty/n_tty.c:1734 n_tty_receive_buf2+0x33/0x40 drivers/tty/n_tty.c:1780 tty_ldisc_receive_buf+0x60/0xe0 drivers/tty/tty_buffer.c:387 tty_port_default_receive_buf+0x59/0x90 drivers/tty/tty_port.c:37 receive_buf drivers/tty/tty_buffer.c:445 [inline] flush_to_ldisc+0x1ca/0x400 drivers/tty/tty_buffer.c:495 process_one_work kernel/workqueue.c:2630 [inline] process_scheduled_works+0x5b8/0xa30 kernel/workqueue.c:2703 worker_thread+0x525/0x730 kernel/workqueue.c:2784 kthread+0x1d7/0x210 kernel/kthread.c:388 ret_from_fork+0x48/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304 value changed: 0x0000000000000008 -> 0x000000000000000e Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 26 Comm: kworker/u4:1 Not tainted 6.6.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/06/2023 Workqueue: events_unbound flush_to_ldisc ==================================================================