[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ 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. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.15.192' (ECDSA) to the list of known hosts. 2020/04/02 09:55:04 fuzzer started 2020/04/02 09:55:06 connecting to host at 10.128.0.26:45395 2020/04/02 09:55:06 checking machine... 2020/04/02 09:55:06 checking revisions... 2020/04/02 09:55:06 testing simple program... syzkaller login: [ 61.244454][ T7039] IPVS: ftp: loaded support on port[0] = 21 2020/04/02 09:55:07 building call list... [ 61.478591][ T573] [ 61.481038][ T573] ============================= [ 61.485875][ T573] WARNING: suspicious RCU usage [ 61.500036][ T573] 5.6.0-next-20200402-syzkaller #0 Not tainted [ 61.513942][ T573] ----------------------------- [ 61.525892][ T573] net/openvswitch/conntrack.c:1898 RCU-list traversed in non-reader section!! [ 61.546105][ T573] [ 61.546105][ T573] other info that might help us debug this: [ 61.546105][ T573] [ 61.570235][ T573] [ 61.570235][ T573] rcu_scheduler_active = 2, debug_locks = 1 [ 61.580478][ T573] 3 locks held by kworker/u4:4/573: [ 61.585762][ T573] #0: ffff8880a977e138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 [ 61.597479][ T573] #1: ffffc90001c97dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 [ 61.597521][ T573] #2: ffffffff8a56fe70 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 [ 61.618058][ T573] [ 61.618058][ T573] stack backtrace: [ 61.624028][ T573] CPU: 1 PID: 573 Comm: kworker/u4:4 Not tainted 5.6.0-next-20200402-syzkaller #0 [ 61.633212][ T573] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.643269][ T573] Workqueue: netns cleanup_net [ 61.648037][ T573] Call Trace: [ 61.651337][ T573] dump_stack+0x188/0x20d [ 61.655680][ T573] ovs_ct_exit+0x3db/0x558 [ 61.660102][ T573] ovs_exit_net+0x1df/0xba0 [ 61.664605][ T573] ? synchronize_rcu.part.0+0xda/0xf0 [ 61.669975][ T573] ? synchronize_rcu_expedited+0x620/0x620 [ 61.675784][ T573] ? ovs_dp_cmd_del+0x270/0x270 [ 61.680638][ T573] ? ovs_dp_cmd_del+0x270/0x270 [ 61.685492][ T573] ops_exit_list.isra.0+0xa8/0x150 [ 61.690609][ T573] cleanup_net+0x511/0xa50 [ 61.695032][ T573] ? unregister_pernet_device+0x70/0x70 [ 61.700582][ T573] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.706648][ T573] ? _raw_spin_unlock_irq+0x1f/0x80 [ 61.711849][ T573] process_one_work+0x965/0x16a0 [ 61.716812][ T573] ? lock_release+0x800/0x800 [ 61.721497][ T573] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.726883][ T573] ? rwlock_bug.part.0+0x90/0x90 [ 61.731847][ T573] worker_thread+0x96/0xe20 [ 61.736365][ T573] ? process_one_work+0x16a0/0x16a0 [ 61.741566][ T573] kthread+0x388/0x470 [ 61.745632][ T573] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.751354][ T573] ret_from_fork+0x24/0x30 [ 61.947306][ T573] tipc: TX() has been purged, node left! [ 61.989543][ T573] [ 61.991981][ T573] ============================= [ 61.996910][ T573] WARNING: suspicious RCU usage [ 62.003735][ T573] 5.6.0-next-20200402-syzkaller #0 Not tainted [ 62.010765][ T573] ----------------------------- [ 62.015683][ T573] net/ipv4/ipmr.c:1757 RCU-list traversed in non-reader section!! [ 62.024677][ T573] [ 62.024677][ T573] other info that might help us debug this: [ 62.024677][ T573] [ 62.035889][ T573] [ 62.035889][ T573] rcu_scheduler_active = 2, debug_locks = 1 [ 62.044724][ T573] 4 locks held by kworker/u4:4/573: [ 62.050750][ T573] #0: ffff8880a977e138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 [ 62.061791][ T573] #1: ffffc90001c97dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 [ 62.072614][ T573] #2: ffffffff8a56fe70 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 [ 62.082776][ T573] #3: ffffffff8a57bde8 (rtnl_mutex){+.+.}-{3:3}, at: ip6gre_exit_batch_net+0x88/0x700 [ 62.093412][ T573] [ 62.093412][ T573] stack backtrace: [ 62.100355][ T573] CPU: 1 PID: 573 Comm: kworker/u4:4 Not tainted 5.6.0-next-20200402-syzkaller #0 [ 62.109558][ T573] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.119632][ T573] Workqueue: netns cleanup_net [ 62.124394][ T573] Call Trace: [ 62.127700][ T573] dump_stack+0x188/0x20d [ 62.132041][ T573] ipmr_device_event+0x240/0x2b0 [ 62.136985][ T573] ? __sanitizer_cov_trace_switch+0x45/0x70 [ 62.142885][ T573] notifier_call_chain+0xc0/0x230 [ 62.147923][ T573] call_netdevice_notifiers_info+0xb5/0x130 [ 62.153823][ T573] rollback_registered_many+0x75c/0xe70 [ 62.159402][ T573] ? netif_set_real_num_tx_queues+0x700/0x700 [ 62.165485][ T573] ? lock_downgrade+0x840/0x840 [ 62.170351][ T573] unregister_netdevice_many.part.0+0x16/0x1e0 [ 62.176527][ T573] unregister_netdevice_many+0x36/0x50 [ 62.181992][ T573] ip6gre_exit_batch_net+0x4e8/0x700 [ 62.187292][ T573] ? ip6gre_tunnel_link+0xf0/0xf0 [ 62.192321][ T573] ? rcu_read_lock_held_common+0x130/0x130 [ 62.198242][ T573] ? ip6gre_tunnel_link+0xf0/0xf0 [ 62.203276][ T573] ops_exit_list.isra.0+0x103/0x150 [ 62.208485][ T573] cleanup_net+0x511/0xa50 [ 62.212911][ T573] ? unregister_pernet_device+0x70/0x70 [ 62.218455][ T573] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.224429][ T573] ? _raw_spin_unlock_irq+0x1f/0x80 [ 62.229629][ T573] process_one_work+0x965/0x16a0 [ 62.234572][ T573] ? lock_release+0x800/0x800 [ 62.239246][ T573] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.244620][ T573] ? rwlock_bug.part.0+0x90/0x90 [ 62.249580][ T573] worker_thread+0x96/0xe20 [ 62.254096][ T573] ? process_one_work+0x16a0/0x16a0 [ 62.259292][ T573] kthread+0x388/0x470 [ 62.263357][ T573] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.269080][ T573] ret_from_fork+0x24/0x30 [ 63.070813][ T7019] can: request_module (can-proto-0) failed. executing program [ 65.431785][ T7019] can: request_module (can-proto-0) failed. [ 65.443418][ T7019] can: request_module (can-proto-0) failed.