[ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.86' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 70.258588][ T8430] BUG: sleeping function called from invalid context at kernel/printk/printk.c:2460 [ 70.268304][ T8430] in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 8430, name: syz-executor396 [ 70.278044][ T8430] 3 locks held by syz-executor396/8430: [ 70.284055][ T8430] #0: ffff88801f8ff098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 [ 70.294580][ T8430] #1: ffff88801f8ff3f8 (&tty->flow_lock){....}-{2:2}, at: n_tty_ioctl_helper+0xcc/0x3a0 [ 70.304663][ T8430] #2: ffff88801f8ff098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref+0x1d/0x80 [ 70.314294][ T8430] irq event stamp: 16848 [ 70.319053][ T8430] hardirqs last enabled at (16847): [] _raw_spin_unlock_irqrestore+0x50/0x70 [ 70.330131][ T8430] hardirqs last disabled at (16848): [] _raw_spin_lock_irq+0x41/0x50 [ 70.340322][ T8430] softirqs last enabled at (15244): [] fpu__clear+0xd3/0x220 [ 70.349653][ T8430] softirqs last disabled at (15242): [] fpu__clear+0x2a/0x220 [ 70.358957][ T8430] Preemption disabled at: [ 70.358968][ T8430] [<0000000000000000>] 0x0 [ 70.367795][ T8430] CPU: 1 PID: 8430 Comm: syz-executor396 Not tainted 5.13.0-rc4-syzkaller #0 [ 70.377528][ T8430] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 70.387800][ T8430] Call Trace: [ 70.391310][ T8430] dump_stack+0x141/0x1d7 [ 70.395781][ T8430] ___might_sleep.cold+0x1f1/0x237 [ 70.401466][ T8430] console_lock+0x19/0x80 [ 70.406546][ T8430] do_con_write+0x10f/0x1e60 [ 70.411501][ T8430] ? n_hdlc_buf_get+0x1a1/0x230 [ 70.417718][ T8430] ? lock_downgrade+0x6e0/0x6e0 [ 70.423025][ T8430] ? do_con_trol+0x54c0/0x54c0 [ 70.428334][ T8430] ? n_hdlc_send_frames+0xf0/0x490 [ 70.434287][ T8430] ? lock_downgrade+0x6e0/0x6e0 [ 70.440239][ T8430] ? do_raw_spin_unlock+0x171/0x230 [ 70.445813][ T8430] ? con_put_char+0xe0/0xe0 [ 70.450484][ T8430] con_write+0x21/0x40 [ 70.454777][ T8430] n_hdlc_send_frames+0x24b/0x490 [ 70.459998][ T8430] ? n_hdlc_send_frames+0x490/0x490 [ 70.465280][ T8430] tty_wakeup+0xe1/0x120 [ 70.469810][ T8430] ? lf+0x2c0/0x2c0 [ 70.473703][ T8430] __start_tty+0x116/0x150 [ 70.478437][ T8430] n_tty_ioctl_helper+0x348/0x3a0 [ 70.483694][ T8430] n_hdlc_tty_ioctl+0xe4/0x360 [ 70.488566][ T8430] tty_ioctl+0xef9/0x1600 [ 70.493199][ T8430] ? n_hdlc_tty_open+0x3e0/0x3e0 [ 70.498141][ T8430] ? tty_lookup_driver+0x550/0x550 [ 70.503343][ T8430] ? find_held_lock+0x2d/0x110 [ 70.508471][ T8430] ? __context_tracking_exit+0xb8/0xe0 [ 70.514144][ T8430] ? lock_downgrade+0x6e0/0x6e0 [ 70.519001][ T8430] ? lock_downgrade+0x6e0/0x6e0 [ 70.523879][ T8430] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 70.530221][ T8430] ? tty_lookup_driver+0x550/0x550 [ 70.535488][ T8430] __x64_sys_ioctl+0x193/0x200 [ 70.540343][ T8430] do_syscall_64+0x3a/0xb0 [ 70.545059][ T8430] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 70.551343][ T8430] RIP: 0033:0x43f159 [ 70.555596][ T8430] Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 [ 70.575874][ T8430] RSP: 002b:00007ffc20312ca8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 70.584295][ T8430] RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043f159 [ 70.592525][ T8430] RDX: 0000000000000001 RSI: 000000000000540a RDI: 0000000000000003 [ 70.600804][ T8430] RBP: 0000000000402fe0 R08: 0000000000400488 R09: 0000000000400488 [ 70.60