================================================================== BUG: KCSAN: data-race in n_tty_receive_char / n_tty_write write to 0xffffc9000a44d028 of 8 bytes by task 8129 on cpu 0: commit_echoes drivers/tty/n_tty.c:742 [inline] n_tty_receive_char+0x437/0x6a0 drivers/tty/n_tty.c:1421 n_tty_receive_buf_standard+0x473/0x2f10 drivers/tty/n_tty.c:1590 __receive_buf drivers/tty/n_tty.c:1624 [inline] n_tty_receive_buf_common+0x805/0xbe0 drivers/tty/n_tty.c:1723 n_tty_receive_buf2+0x33/0x40 drivers/tty/n_tty.c:1769 tty_ldisc_receive_buf+0x63/0xf0 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+0x141/0x360 drivers/tty/tty_buffer.c:495 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0x4cb/0x9d0 kernel/workqueue.c:3321 worker_thread+0x582/0x770 kernel/workqueue.c:3402 kthread+0x489/0x510 kernel/kthread.c:464 ret_from_fork+0xda/0x150 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 read to 0xffffc9000a44d028 of 8 bytes by task 20639 on cpu 1: process_echoes drivers/tty/n_tty.c:768 [inline] n_tty_write+0x14f/0xb10 drivers/tty/n_tty.c:2363 iterate_tty_write drivers/tty/tty_io.c:1006 [inline] file_tty_write+0x38c/0x670 drivers/tty/tty_io.c:1081 tty_write+0x25/0x30 drivers/tty/tty_io.c:1102 new_sync_write fs/read_write.c:593 [inline] vfs_write+0x4a0/0x8e0 fs/read_write.c:686 ksys_write+0xda/0x1a0 fs/read_write.c:738 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x40/0x50 fs/read_write.c:746 x64_sys_call+0x2cdd/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x0000000000000004 -> 0x0000000000000008 Reported by Kernel Concurrency Sanitizer on: CPU: 1 UID: 0 PID: 20639 Comm: syz.0.5323 Not tainted 6.16.0-rc4-syzkaller-00319-g05df91921da6 #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 ==================================================================