[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 39.006199] audit: type=1800 audit(1545705364.189:25): pid=7730 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 39.026295] audit: type=1800 audit(1545705364.189:26): pid=7730 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 39.061414] audit: type=1800 audit(1545705364.199:27): pid=7730 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.83' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 51.985468] ------------[ cut here ]------------ [ 51.990508] do not call blocking ops when !TASK_RUNNING; state=1 set at [<000000004f3f4048>] n_hdlc_tty_read+0x301/0x7f0 [ 52.002040] WARNING: CPU: 0 PID: 7881 at kernel/sched/core.c:6099 __might_sleep+0x13d/0x190 [ 52.010687] Kernel panic - not syncing: panic_on_warn set ... [ 52.016566] CPU: 0 PID: 7881 Comm: syz-executor958 Not tainted 4.20.0 #166 [ 52.023573] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 52.033154] Call Trace: [ 52.035862] dump_stack+0x1d3/0x2c6 [ 52.039776] ? dump_stack_print_info.cold.1+0x20/0x20 [ 52.045082] panic+0x2ad/0x55c [ 52.048275] ? add_taint.cold.5+0x16/0x16 [ 52.052550] ? __warn.cold.8+0x5/0x45 [ 52.056614] ? __warn+0xe8/0x1d0 [ 52.059978] ? __might_sleep+0x13d/0x190 [ 52.064045] __warn.cold.8+0x20/0x45 [ 52.067756] ? rcu_softirq_qs+0x20/0x20 [ 52.071720] ? __might_sleep+0x13d/0x190 [ 52.075881] report_bug+0x254/0x2d0 [ 52.079514] do_error_trap+0x11b/0x200 [ 52.083657] do_invalid_op+0x36/0x40 [ 52.087365] ? __might_sleep+0x13d/0x190 [ 52.091423] invalid_op+0x14/0x20 [ 52.094890] RIP: 0010:__might_sleep+0x13d/0x190 [ 52.099674] Code: 65 48 8b 1c 25 40 ee 01 00 48 8d 7b 10 48 89 fe 48 c1 ee 03 80 3c 06 00 75 2b 48 8b 73 10 48 c7 c7 40 e0 2a 88 e8 43 27 f3 ff <0f> 0b e9 43 ff ff ff e8 f7 7c 6c 00 e9 26 ff ff ff e8 ed 7c 6c 00 [ 52.119522] RSP: 0018:ffff8881bcfcf948 EFLAGS: 00010286 [ 52.124881] RAX: 0000000000000000 RBX: ffff8881b15e4200 RCX: 0000000000000000 [ 52.132426] RDX: 0000000000000000 RSI: ffffffff8164e045 RDI: 0000000000000005 [ 52.139726] RBP: ffff8881bcfcf978 R08: ffff8881b15e4200 R09: 0000000000000007 [ 52.147236] R10: 0000000000000000 R11: ffff8881b15e4200 R12: ffffffff8860b220 [ 52.154601] R13: 0000000000000019 R14: 0000000000000000 R15: ffff8881b15e4200 [ 52.162005] ? vprintk_func+0x85/0x181 [ 52.165910] ? __might_sleep+0x13d/0x190 [ 52.169986] __might_fault+0xc6/0x1e0 [ 52.173793] _copy_to_user+0x30/0x110 [ 52.177606] n_hdlc_tty_read+0x5c1/0x7f0 [ 52.181680] ? n_hdlc_tty_poll+0x5f0/0x5f0 [ 52.185925] ? wake_up_q+0x100/0x100 [ 52.189766] ? ldsem_down_read+0x32/0x40 [ 52.193834] ? ldsem_down_read+0x32/0x40 [ 52.197902] tty_read+0x194/0x2a0 [ 52.201366] ? n_hdlc_tty_poll+0x5f0/0x5f0 [ 52.205618] __vfs_read+0x117/0x9b0 [ 52.209429] ? __fget_light+0x2e9/0x430 [ 52.213960] ? tty_poll+0x1a0/0x1a0 [ 52.217600] ? vfs_copy_file_range+0xb90/0xb90 [ 52.222294] ? rcu_dynticks_curr_cpu_in_eqs+0xa2/0x170 [ 52.227597] ? tty_vhangup+0x30/0x30 [ 52.231326] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 52.237185] ? do_vfs_ioctl+0x201/0x1790 [ 52.241246] ? ioctl_preallocate+0x300/0x300 [ 52.245664] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 52.251318] ? security_file_permission+0x1c2/0x230 [ 52.256350] ? rw_verify_area+0x118/0x360 [ 52.260505] vfs_read+0x17f/0x3c0 [ 52.264084] ksys_read+0x101/0x260 [ 52.267812] ? kernel_write+0x120/0x120 [ 52.271809] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 52.277284] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 52.282964] ? ksys_ioctl+0x81/0xd0 [ 52.286609] __x64_sys_read+0x73/0xb0 [ 52.290426] do_syscall_64+0x1b9/0x820 [ 52.294488] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 52.299875] ? syscall_return_slowpath+0x5e0/0x5e0 [ 52.304907] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 52.309781] ? trace_hardirqs_on_caller+0x310/0x310 [ 52.314827] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 52.319862] ? prepare_exit_to_usermode+0x291/0x3b0 [ 52.324897] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 52.329765] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 52.334965] RIP: 0033:0x440099 [ 52.338163] Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 0f 83 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 52.357307] RSP: 002b:00007fff572636e8 EFLAGS: 00000207 ORIG_RAX: 0000000000000000 [ 52.366888] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440099 [ 52.374319] RDX: 0000000000000057 RSI: 0000000020000080 RDI: 0000000000000003 [ 52.381606] RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 [ 52.388998] R10: 00000000004002c8 R11: 0000000000000207 R12: 0000000000401920 [ 52.396283] R13: 00000000004019b0 R14: 0000000000000000 R15: 0000000000000000 [ 52.404809] Kernel Offset: disabled [ 52.408546] Rebooting in 86400 seconds..