[ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Load/Save RF Kill Switch Status. [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.45' (ECDSA) to the list of known hosts. syzkaller login: [ 64.444635][ T7123] IPVS: ftp: loaded support on port[0] = 21 [ 64.452317][ T7125] IPVS: ftp: loaded support on port[0] = 21 [ 64.462549][ T7126] IPVS: ftp: loaded support on port[0] = 21 [ 64.471640][ T7127] IPVS: ftp: loaded support on port[0] = 21 [ 64.477169][ T7122] IPVS: ftp: loaded support on port[0] = 21 [ 64.487414][ T7124] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 65.063005][ T3101] ------------[ cut here ]------------ [ 65.069093][ T3101] refcount_t: underflow; use-after-free. executing program executing program [ 65.104182][ T3101] WARNING: CPU: 1 PID: 3101 at lib/refcount.c:28 refcount_warn_saturate+0x1d1/0x1e0 [ 65.113588][ T3101] Kernel panic - not syncing: panic_on_warn set ... [ 65.120193][ T3101] CPU: 1 PID: 3101 Comm: kworker/1:64 Not tainted 5.7.0-rc1-next-20200415-syzkaller #0 [ 65.130206][ T3101] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 65.140297][ T3101] Workqueue: events do_enable_set [ 65.145321][ T3101] Call Trace: [ 65.148614][ T3101] dump_stack+0x188/0x20d executing program [ 65.152953][ T3101] ? refcount_warn_saturate+0x100/0x1e0 [ 65.158499][ T3101] panic+0x2e3/0x75c [ 65.162399][ T3101] ? add_taint.cold+0x16/0x16 [ 65.167088][ T3101] ? __probe_kernel_read+0x188/0x1d0 [ 65.172376][ T3101] ? __warn.cold+0x14/0x35 [ 65.176817][ T3101] ? __warn+0xd5/0x1c8 [ 65.180980][ T3101] ? refcount_warn_saturate+0x1d1/0x1e0 [ 65.186536][ T3101] __warn.cold+0x2f/0x35 [ 65.190804][ T3101] ? refcount_warn_saturate+0x1d1/0x1e0 [ 65.196359][ T3101] report_bug+0x27b/0x2f0 executing program executing program [ 65.200712][ T3101] do_error_trap+0x12b/0x220 [ 65.205307][ T3101] ? refcount_warn_saturate+0x1d1/0x1e0 [ 65.210869][ T3101] do_invalid_op+0x32/0x40 [ 65.215310][ T3101] ? refcount_warn_saturate+0x1d1/0x1e0 [ 65.220873][ T3101] invalid_op+0x23/0x30 [ 65.225039][ T3101] RIP: 0010:refcount_warn_saturate+0x1d1/0x1e0 [ 65.231208][ T3101] Code: e9 db fe ff ff 48 89 df e8 0c 3d 1a fe e9 8a fe ff ff e8 d2 1b dc fd 48 c7 c7 c0 74 72 88 c6 05 31 7b ef 06 01 e8 97 50 ad fd <0f> 0b e9 af fe ff ff 0f 1f 84 00 00 00 00 00 41 56 41 55 41 54 55 executing program executing program [ 65.250818][ T3101] RSP: 0018:ffffc90001257be8 EFLAGS: 00010282 [ 65.256892][ T3101] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 65.264875][ T3101] RDX: 0000000000000000 RSI: ffffffff815ce211 RDI: fffff5200024af6f [ 65.272854][ T3101] RBP: 0000000000000003 R08: ffff8880a88ea140 R09: ffffed1015ce66b1 [ 65.280979][ T3101] R10: ffff8880ae733587 R11: ffffed1015ce66b0 R12: ffff888093bce018 [ 65.288957][ T3101] R13: ffff888097870800 R14: ffff8880a87b3900 R15: ffff8880ae7371c0 [ 65.296957][ T3101] ? vprintk_func+0x81/0x17e executing program [ 65.301562][ T3101] ? refcount_warn_saturate+0x1d1/0x1e0 [ 65.307211][ T3101] l2cap_chan_put+0x1d3/0x230 [ 65.311899][ T3101] do_enable_set+0x4db/0x8e0 [ 65.316503][ T3101] ? lowpan_control_write+0x480/0x480 [ 65.321885][ T3101] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 65.327439][ T3101] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 65.333441][ T3101] ? _raw_spin_unlock_irq+0x1f/0x80 [ 65.338669][ T3101] process_one_work+0x965/0x16a0 [ 65.343621][ T3101] ? lock_release+0x800/0x800 [ 65.348310][ T3101] ? pwq_dec_nr_in_flight+0x310/0x310 [ 65.353955][ T3101] ? rwlock_bug.part.0+0x90/0x90 [ 65.358911][ T3101] worker_thread+0x96/0xe20 [ 65.363464][ T3101] ? process_one_work+0x16a0/0x16a0 [ 65.368678][ T3101] kthread+0x388/0x470 [ 65.372999][ T3101] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 65.378738][ T3101] ret_from_fork+0x24/0x30 [ 65.384741][ T3101] Kernel Offset: disabled [ 65.389186][ T3101] Rebooting in 86400 seconds..