[  OK  ] Started Regular background program processing daemon.
[  OK  ] Started Daily apt upgrade and clean activities.
         Starting System Logging Service...
[  OK  ] Started Daily Cleanup of Temporary Directories.
[  OK  ] Reached target Timers.
[  OK  ] Started Permit User Sessions.
[  OK  ] Started System Logging Service.
[  OK  ] Found device /dev/ttyS0.
[  OK  ] Started OpenBSD Secure Shell server.
[  OK  ] Started getty on tty2-tty6 if dbus and logind are not available.
[  OK  ] Listening on Load/Save RF Kill Switch Status /dev/rfkill Watch.
[  OK  ] Started Getty on tty6.
[  OK  ] Started Getty on tty5.
[  OK  ] Started Getty on tty4.
[  OK  ] Started Getty on tty3.
[  OK  ] Started Getty on tty2.
[  OK  ] Started Getty on tty1.
[  OK  ] Started Serial Getty on ttyS0.
[  OK  ] Reached target Login Prompts.
[  OK  ] Reached target Multi-User System.
[  OK  ] Reached target Graphical Interface.
         Starting Update UTMP about System Runlevel Changes...
         Starting Load/Save RF Kill Switch Status...
[  OK  ] Started Update UTMP about System Runlevel Changes.
[  OK  ] Started Load/Save RF Kill Switch Status.


Debian GNU/Linux 9 syzkaller ttyS0

Warning: Permanently added '10.128.0.141' (ECDSA) to the list of known hosts.
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syzkaller login: [   64.655322][   T27] audit: type=1400 audit(1601126268.906:8): avc:  denied  { execmem } for  pid=6889 comm="syz-executor703" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1
[   64.669962][ T6890] IPVS: ftp: loaded support on port[0] = 21
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[   65.091932][  T199] ------------[ cut here ]------------
[   65.097516][  T199] refcount_t: addition on 0; use-after-free.
[   65.103699][  T199] WARNING: CPU: 0 PID: 199 at lib/refcount.c:25 refcount_warn_saturate+0x169/0x1e0
[   65.112953][  T199] Kernel panic - not syncing: panic_on_warn set ...
[   65.119527][  T199] CPU: 0 PID: 199 Comm: kworker/u4:5 Not tainted 5.9.0-rc6-syzkaller #0
[   65.127819][  T199] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   65.138115][  T199] Workqueue: qrtr_ns_handler qrtr_ns_worker
[   65.143976][  T199] Call Trace:
[   65.147244][  T199]  dump_stack+0x198/0x1fd
[   65.151554][  T199]  panic+0x382/0x7fb
[   65.155423][  T199]  ? __warn_printk+0xf3/0xf3
[   65.160002][  T199]  ? _raw_spin_unlock+0x24/0x40
[   65.164829][  T199]  ? __printk_safe_exit+0x5/0x10
[   65.169750][  T199]  ? console_unlock+0x733/0xe60
[   65.174577][  T199]  ? __warn.cold+0x5/0x4b
[   65.178967][  T199]  ? __warn+0xd6/0x1f2
[   65.183014][  T199]  ? refcount_warn_saturate+0x169/0x1e0
[   65.188546][  T199]  __warn.cold+0x20/0x4b
[   65.192764][  T199]  ? wake_up_klogd.part.0+0x8e/0xd0
[   65.197936][  T199]  ? refcount_warn_saturate+0x169/0x1e0
[   65.203469][  T199]  report_bug+0x1bd/0x210
[   65.207777][  T199]  handle_bug+0x38/0x90
[   65.211910][  T199]  exc_invalid_op+0x14/0x40
[   65.216414][  T199]  asm_exc_invalid_op+0x12/0x20
[   65.221248][  T199] RIP: 0010:refcount_warn_saturate+0x169/0x1e0
[   65.227376][  T199] Code: 07 31 ff 89 de e8 a7 58 b6 fd 84 db 0f 85 36 ff ff ff e8 7a 5c b6 fd 48 c7 c7 40 71 d8 88 c6 05 35 99 94 07 01 e8 e9 99 86 fd <0f> 0b e9 17 ff ff ff e8 5b 5c b6 fd 0f b6 1d 1a 99 94 07 31 ff 89
[   65.246955][  T199] RSP: 0018:ffffc900018079d8 EFLAGS: 00010086
[   65.252995][  T199] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[   65.260952][  T199] RDX: ffff8880a8a52300 RSI: ffffffff815f5985 RDI: fffff52000300f2d
[   65.268910][  T199] RBP: 0000000000000002 R08: 0000000000000001 R09: ffff8880ae420f8b
[   65.276856][  T199] R10: 0000000000000000 R11: 0000000000000000 R12: ffff88821b0b8040
[   65.284889][  T199] R13: ffff88809f407400 R14: ffff8880a0abd670 R15: ffff8880a0abd674
[   65.292859][  T199]  ? vprintk_func+0x95/0x1d4
[   65.297451][  T199]  ? refcount_warn_saturate+0x169/0x1e0
[   65.302971][  T199]  qrtr_recvmsg+0x845/0x970
[   65.307455][  T199]  ? qrtr_node_enqueue+0x1250/0x1250
[   65.312727][  T199]  ? lock_is_held_type+0xbb/0xf0
[   65.317645][  T199]  ? bpf_lsm_socket_recvmsg+0x5/0x10
[   65.322930][  T199]  ? security_socket_recvmsg+0x8f/0xc0
[   65.328450][  T199]  ? qrtr_node_enqueue+0x1250/0x1250
[   65.333717][  T199]  kernel_recvmsg+0x110/0x160
[   65.338372][  T199]  qrtr_ns_worker+0x15a/0x153b
[   65.343123][  T199]  ? lockdep_hardirqs_on_prepare+0x530/0x530
[   65.349093][  T199]  ? ctrl_cmd_del_client+0x730/0x730
[   65.354356][  T199]  ? lock_acquire+0x1f3/0xaf0
[   65.359032][  T199]  ? process_one_work+0x85f/0x1670
[   65.364179][  T199]  ? _raw_spin_unlock_irq+0x1f/0x80
[   65.369362][  T199]  ? lock_is_held_type+0xbb/0xf0
[   65.374282][  T199]  process_one_work+0x94c/0x1670
[   65.379243][  T199]  ? lock_release+0x8f0/0x8f0
[   65.383898][  T199]  ? pwq_dec_nr_in_flight+0x320/0x320
[   65.389258][  T199]  ? rwlock_bug.part.0+0x90/0x90
[   65.394181][  T199]  ? lockdep_hardirqs_off+0x96/0xd0
[   65.399359][  T199]  worker_thread+0x64c/0x1120
[   65.404019][  T199]  ? process_one_work+0x1670/0x1670
[   65.409193][  T199]  kthread+0x3b5/0x4a0
[   65.413238][  T199]  ? __kthread_bind_mask+0xc0/0xc0
[   65.418329][  T199]  ret_from_fork+0x1f/0x30
[   66.517366][  T199] Shutting down cpus with NMI
[   66.523322][  T199] Kernel Offset: disabled
[   66.527702][  T199] Rebooting in 86400 seconds..