Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [ 93.290034][ T26] audit: type=1400 audit(1583357465.697:37): avc: denied { watch } for pid=10478 comm="restorecond" path="/root/.ssh" dev="sda1" ino=16179 scontext=system_u:system_r:kernel_t:s0 tcontext=unconfined_u:object_r:ssh_home_t:s0 tclass=dir permissive=1 [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 97.485677][ T26] kauditd_printk_skb: 3 callbacks suppressed [ 97.485691][ T26] audit: type=1400 audit(1583357469.887:41): avc: denied { map } for pid=10570 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 Warning: Permanently added '10.128.0.232' (ECDSA) to the list of known hosts. 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 [ 104.583848][ T26] audit: type=1400 audit(1583357476.987:42): avc: denied { map } for pid=10582 comm="syz-executor280" path="/root/syz-executor280923163" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 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 [ 104.660320][ T26] audit: type=1400 audit(1583357476.987:43): avc: denied { integrity } for pid=10590 comm="syz-executor280" lockdown_reason="debugfs access" scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=lockdown permissive=1 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 [ 105.025823][ T2828] ------------[ cut here ]------------ [ 105.032172][ T2828] refcount_t: underflow; use-after-free. [ 105.055508][ T2828] WARNING: CPU: 1 PID: 2828 at lib/refcount.c:28 refcount_warn_saturate+0x1dc/0x1f0 [ 105.064909][ T2828] Kernel panic - not syncing: panic_on_warn set ... [ 105.071512][ T2828] CPU: 1 PID: 2828 Comm: kworker/1:82 Not tainted 5.6.0-rc3-syzkaller #0 [ 105.079950][ T2828] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 105.090026][ T2828] Workqueue: events do_enable_set [ 105.095128][ T2828] Call Trace: [ 105.098429][ T2828] dump_stack+0x197/0x210 [ 105.102775][ T2828] ? refcount_warn_saturate+0x1b0/0x1f0 [ 105.108334][ T2828] panic+0x2e3/0x75c [ 105.112242][ T2828] ? add_taint.cold+0x16/0x16 [ 105.116966][ T2828] ? __kasan_check_write+0x14/0x20 [ 105.122195][ T2828] ? __warn.cold+0x14/0x3e [ 105.126618][ T2828] ? __warn+0xd9/0x1cf [ 105.130708][ T2828] ? refcount_warn_saturate+0x1dc/0x1f0 [ 105.136267][ T2828] __warn.cold+0x2f/0x3e [ 105.140534][ T2828] ? refcount_warn_saturate+0x1dc/0x1f0 [ 105.146107][ T2828] report_bug+0x289/0x300 [ 105.150459][ T2828] do_error_trap+0x11b/0x200 [ 105.155078][ T2828] do_invalid_op+0x37/0x50 [ 105.159505][ T2828] ? refcount_warn_saturate+0x1dc/0x1f0 [ 105.165073][ T2828] invalid_op+0x23/0x30 [ 105.169240][ T2828] RIP: 0010:refcount_warn_saturate+0x1dc/0x1f0 [ 105.175574][ T2828] 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 [ 105.195215][ T2828] RSP: 0018:ffffc9000894fbd8 EFLAGS: 00010286 [ 105.201294][ T2828] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 [ 105.209273][ T2828] RDX: 0000000000000000 RSI: ffffffff815ebe46 RDI: fffff52001129f6d [ 105.217253][ T2828] RBP: ffffc9000894fbe8 R08: ffff88809f0e24c0 R09: ffffed1015d26659 [ 105.225237][ T2828] R10: ffffed1015d26658 R11: ffff8880ae9332c7 R12: 0000000000000003 [ 105.233217][ T2828] R13: ffff88809f592018 R14: ffff8880a8779d00 R15: ffff88809f015c00 [ 105.241339][ T2828] ? vprintk_func+0x86/0x189 [ 105.245962][ T2828] ? refcount_warn_saturate+0x1dc/0x1f0 [ 105.251524][ T2828] l2cap_chan_put+0x1d9/0x240 [ 105.256230][ T2828] do_enable_set+0x54b/0x960 [ 105.260850][ T2828] ? rcu_lockdep_current_cpu_online+0xe3/0x130 [ 105.267053][ T2828] ? lowpan_control_write+0x4b0/0x4b0 [ 105.272469][ T2828] ? rcu_read_lock_sched_held+0x9c/0xd0 [ 105.278028][ T2828] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 105.284046][ T2828] ? trace_hardirqs_on+0x67/0x240 [ 105.289096][ T2828] process_one_work+0xa05/0x17a0 [ 105.294080][ T2828] ? mark_held_locks+0xf0/0xf0 [ 105.298968][ T2828] ? pwq_dec_nr_in_flight+0x320/0x320 [ 105.304356][ T2828] ? lock_acquire+0x190/0x410 [ 105.309065][ T2828] worker_thread+0x98/0xe40 [ 105.313613][ T2828] kthread+0x361/0x430 [ 105.317735][ T2828] ? process_one_work+0x17a0/0x17a0 [ 105.322955][ T2828] ? kthread_mod_delayed_work+0x1f0/0x1f0 [ 105.328701][ T2828] ret_from_fork+0x24/0x30 [ 105.334350][ T2828] Kernel Offset: disabled [ 105.338762][ T2828] Rebooting in 86400 seconds..