================================================================== BUG: KCSAN: data-race in n_tty_receive_buf_common / n_tty_write write to 0xffffc900074d1020 of 8 bytes by task 7508 on cpu 0: process_echoes drivers/tty/n_tty.c:788 [inline] n_tty_write+0x1bc/0xb90 drivers/tty/n_tty.c:2365 iterate_tty_write drivers/tty/tty_io.c:1021 [inline] file_tty_write+0x386/0x690 drivers/tty/tty_io.c:1096 tty_write+0x28/0x30 drivers/tty/tty_io.c:1117 do_iter_readv_writev+0x339/0x3e0 vfs_writev+0x2e9/0x860 fs/read_write.c:971 do_writev+0xf8/0x220 fs/read_write.c:1018 __do_sys_writev fs/read_write.c:1091 [inline] __se_sys_writev fs/read_write.c:1088 [inline] __x64_sys_writev+0x45/0x50 fs/read_write.c:1088 do_syscall_64+0xd3/0x1d0 entry_SYSCALL_64_after_hwframe+0x6d/0x75 read to 0xffffc900074d1020 of 8 bytes by task 10 on cpu 1: flush_echoes drivers/tty/n_tty.c:802 [inline] __receive_buf drivers/tty/n_tty.c:1632 [inline] n_tty_receive_buf_common+0x87d/0xbd0 drivers/tty/n_tty.c:1729 n_tty_receive_buf2+0x33/0x40 drivers/tty/n_tty.c:1775 tty_ldisc_receive_buf+0x63/0x100 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+0x1ce/0x410 drivers/tty/tty_buffer.c:495 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0x465/0x990 kernel/workqueue.c:3335 worker_thread+0x526/0x730 kernel/workqueue.c:3416 kthread+0x1d1/0x210 kernel/kthread.c:388 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:243 value changed: 0x000000000000396a -> 0x000000000000396c Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 10 Comm: kworker/u8:0 Not tainted 6.8.0-syzkaller-13161-gbfa8f18691ed #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024 Workqueue: events_unbound flush_to_ldisc ================================================================== netdevsim netdevsim1 netdevsim3 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim1 netdevsim2 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim1 netdevsim1 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 netdevsim netdevsim1 netdevsim0 (unregistering): unset [1, 0] type 2 family 0 port 6081 - 0 bridge_slave_1: left allmulticast mode bridge_slave_1: left promiscuous mode bridge0: port 2(bridge_slave_1) entered disabled state bridge_slave_0: left allmulticast mode bridge_slave_0: left promiscuous mode bridge0: port 1(bridge_slave_0) entered disabled state bond0 (unregistering): (slave bond_slave_0): Releasing backup interface bond0 (unregistering): (slave bond_slave_1): Releasing backup interface bond0 (unregistering): Released all slaves hsr_slave_0: left promiscuous mode hsr_slave_1: left promiscuous mode batman_adv: batadv0: Interface deactivated: batadv_slave_0 batman_adv: batadv0: Removing interface: batadv_slave_0 batman_adv: batadv0: Interface deactivated: batadv_slave_1 batman_adv: batadv0: Removing interface: batadv_slave_1 veth1_macvtap: left promiscuous mode veth0_macvtap: left promiscuous mode veth1_vlan: left promiscuous mode veth0_vlan: left promiscuous mode team0 (unregistering): Port device team_slave_1 removed team0 (unregistering): Port device team_slave_0 removed