[  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 '10.128.1.28' (ECDSA) to the list of known hosts.
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syzkaller login: [   51.057589][ T3832] ------------[ cut here ]------------
[   51.063607][ T3832] refcount_t: underflow; use-after-free.
[   51.082852][ T3832] WARNING: CPU: 0 PID: 3832 at lib/refcount.c:28 refcount_warn_saturate+0x15b/0x1a0
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[   51.115783][ T3832] Kernel panic - not syncing: panic_on_warn set ...
[   51.122395][ T3832] CPU: 0 PID: 3832 Comm: kworker/0:10 Not tainted 5.8.0-syzkaller #0
[   51.130445][ T3832] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[   51.140501][ T3832] Workqueue: events do_enable_set
[   51.145516][ T3832] Call Trace:
[   51.148804][ T3832]  dump_stack+0x1f0/0x31e
[   51.153134][ T3832]  panic+0x264/0x7a0
[   51.157030][ T3832]  ? __warn+0x102/0x250
[   51.161189][ T3832]  ? refcount_warn_saturate+0x15b/0x1a0
[   51.166730][ T3832]  ? refcount_warn_saturate+0x15b/0x1a0
[   51.172297][ T3832]  __warn+0x227/0x250
[   51.176282][ T3832]  ? refcount_warn_saturate+0x15b/0x1a0
[   51.181827][ T3832]  report_bug+0x1b1/0x2e0
[   51.186159][ T3832]  handle_bug+0x42/0x80
[   51.190314][ T3832]  exc_invalid_op+0x16/0x40
[   51.194812][ T3832]  asm_exc_invalid_op+0x12/0x20
[   51.199659][ T3832] RIP: 0010:refcount_warn_saturate+0x15b/0x1a0
[   51.205803][ T3832] Code: c7 8a af 14 89 31 c0 e8 b3 f2 a8 fd 0f 0b eb 85 e8 2a 32 d7 fd c6 05 a4 d9 eb 05 01 48 c7 c7 b6 af 14 89 31 c0 e8 95 f2 a8 fd <0f> 0b e9 64 ff ff ff e8 09 32 d7 fd c6 05 84 d9 eb 05 01 48 c7 c7
[   51.225400][ T3832] RSP: 0018:ffffc90001637c48 EFLAGS: 00010246
[   51.231457][ T3832] RAX: 8e8a43e63c14f100 RBX: 0000000000000003 RCX: ffff8880a8e903c0
[   51.239425][ T3832] RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
[   51.247390][ T3832] RBP: 0000000000000003 R08: ffffffff815dd389 R09: ffffed1015d062c0
[   51.255357][ T3832] R10: ffffed1015d062c0 R11: 0000000000000000 R12: dffffc0000000000
[   51.263322][ T3832] R13: ffff8880a96bd218 R14: dffffc0000000000 R15: ffff8880ae8350c0
[   51.271324][ T3832]  ? vprintk_emit+0x339/0x3c0
[   51.276031][ T3832]  ? refcount_warn_saturate+0x15b/0x1a0
[   51.281574][ T3832]  do_enable_set+0x66e/0x900
[   51.286162][ T3832]  ? lock_is_held_type+0x87/0xe0
[   51.291104][ T3832]  process_one_work+0x789/0xfc0
[   51.295991][ T3832]  worker_thread+0xaa4/0x1460
[   51.300672][ T3832]  ? _raw_spin_unlock_irqrestore+0x6f/0xd0
[   51.306490][ T3832]  kthread+0x37e/0x3a0
[   51.310554][ T3832]  ? rcu_lock_release+0x20/0x20
[   51.315400][ T3832]  ? kthread_blkcg+0xd0/0xd0
[   51.320018][ T3832]  ret_from_fork+0x1f/0x30
[   51.325610][ T3832] Kernel Offset: disabled
[   51.329966][ T3832] Rebooting in 86400 seconds..