[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 68.598658][ T26] audit: type=1800 audit(1583226023.091:25): pid=9470 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 68.619826][ T26] audit: type=1800 audit(1583226023.091:26): pid=9470 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 68.663690][ T26] audit: type=1800 audit(1583226023.091:27): pid=9470 uid=0 auid=4294967295 ses=4294967295 subj==unconfined 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 '10.128.0.72' (ECDSA) to the list of known hosts. syzkaller login: [ 80.061237][ T9627] IPVS: ftp: loaded support on port[0] = 21 [ 80.068250][ T9631] IPVS: ftp: loaded support on port[0] = 21 [ 80.070447][ T9633] IPVS: ftp: loaded support on port[0] = 21 [ 80.083409][ T9634] IPVS: ftp: loaded support on port[0] = 21 [ 80.094946][ T9632] IPVS: ftp: loaded support on port[0] = 21 [ 80.102585][ T9635] 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 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 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 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 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 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 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 executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 80.603587][ T2910] ------------[ cut here ]------------ [ 80.609483][ T2910] refcount_t: underflow; use-after-free. [ 80.630560][ T2910] WARNING: CPU: 0 PID: 2910 at lib/refcount.c:28 refcount_warn_saturate+0x1dc/0x1f0 [ 80.639951][ T2910] Kernel panic - not syncing: panic_on_warn set ... executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 80.646628][ T2910] CPU: 0 PID: 2910 Comm: kworker/0:4 Not tainted 5.6.0-rc3-syzkaller #0 [ 80.654949][ T2910] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 80.665025][ T2910] Workqueue: events do_enable_set [ 80.670076][ T2910] Call Trace: [ 80.673378][ T2910] dump_stack+0x197/0x210 [ 80.677722][ T2910] ? refcount_warn_saturate+0x1b0/0x1f0 [ 80.683279][ T2910] panic+0x2e3/0x75c [ 80.687178][ T2910] ? add_taint.cold+0x16/0x16 [ 80.691874][ T2910] ? __kasan_check_write+0x14/0x20 [ 80.696992][ T2910] ? __warn.cold+0x14/0x3e executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 80.701420][ T2910] ? __warn+0xd9/0x1cf [ 80.705516][ T2910] ? refcount_warn_saturate+0x1dc/0x1f0 [ 80.711075][ T2910] __warn.cold+0x2f/0x3e [ 80.715327][ T2910] ? refcount_warn_saturate+0x1dc/0x1f0 [ 80.720887][ T2910] report_bug+0x289/0x300 [ 80.725232][ T2910] do_error_trap+0x11b/0x200 [ 80.729842][ T2910] do_invalid_op+0x37/0x50 [ 80.734265][ T2910] ? refcount_warn_saturate+0x1dc/0x1f0 [ 80.739821][ T2910] invalid_op+0x23/0x30 [ 80.743991][ T2910] RIP: 0010:refcount_warn_saturate+0x1dc/0x1f0 executing program executing program executing program executing program executing program executing program executing program executing program [ 80.750148][ T2910] Code: e9 d8 fe ff ff 48 89 df e8 71 67 11 fe e9 85 fe ff ff e8 37 c1 d2 fd 48 c7 c7 40 9d 91 88 c6 05 5f 38 fe 06 01 e8 c3 12 a3 fd <0f> 0b e9 ac fe ff ff 0f 1f 00 66 2e 0f 1f 84 00 00 00 00 00 55 48 [ 80.769755][ T2910] RSP: 0018:ffffc90008867bd8 EFLAGS: 00010286 [ 80.775826][ T2910] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 80.789876][ T2910] RDX: 0000000000000000 RSI: ffffffff815ebe46 RDI: fffff5200110cf6d executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 80.797851][ T2910] RBP: ffffc90008867be8 R08: ffff88809f1c6600 R09: ffffed1015d06659 [ 80.805825][ T2910] R10: ffffed1015d06658 R11: ffff8880ae8332c7 R12: 0000000000000003 [ 80.813801][ T2910] R13: ffff8880a108d018 R14: ffff8880a077a000 R15: ffff88809f145b00 [ 80.821819][ T2910] ? vprintk_func+0x86/0x189 [ 80.826428][ T2910] ? refcount_warn_saturate+0x1dc/0x1f0 [ 80.832084][ T2910] l2cap_chan_put+0x1d9/0x240 [ 80.836777][ T2910] do_enable_set+0x54b/0x960 [ 80.841394][ T2910] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 80.847555][ T2910] ? lowpan_control_write+0x4b0/0x4b0 executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 80.852945][ T2910] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 80.858519][ T2910] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 80.864505][ T2910] ? trace_hardirqs_on+0x67/0x240 [ 80.869551][ T2910] process_one_work+0xa05/0x17a0 [ 80.874502][ T2910] ? mark_held_locks+0xf0/0xf0 [ 80.879294][ T2910] ? pwq_dec_nr_in_flight+0x320/0x320 [ 80.884668][ T2910] ? lock_acquire+0x190/0x410 [ 80.889377][ T2910] worker_thread+0x98/0xe40 [ 80.893894][ T2910] ? trace_hardirqs_on+0x67/0x240 [ 80.898950][ T2910] kthread+0x361/0x430 executing program executing program [ 80.903030][ T2910] ? process_one_work+0x17a0/0x17a0 [ 80.908238][ T2910] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 80.913973][ T2910] ret_from_fork+0x24/0x30 [ 80.919733][ T2910] Kernel Offset: disabled [ 80.924113][ T2910] Rebooting in 86400 seconds..