[ 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 '10.128.1.56' (ECDSA) to the list of known hosts. 2020/04/17 05:15:12 fuzzer started 2020/04/17 05:15:14 connecting to host at 10.128.0.26:35667 2020/04/17 05:15:14 checking machine... 2020/04/17 05:15:14 checking revisions... 2020/04/17 05:15:14 testing simple program... syzkaller login: [ 60.963749][ T6837] IPVS: ftp: loaded support on port[0] = 21 2020/04/17 05:15:14 building call list... [ 61.201837][ T21] [ 61.204319][ T21] ============================= [ 61.211036][ T21] WARNING: suspicious RCU usage [ 61.216036][ T21] 5.7.0-rc1-next-20200417-syzkaller #0 Not tainted [ 61.225354][ T21] ----------------------------- [ 61.231237][ T21] net/openvswitch/conntrack.c:1898 RCU-list traversed in non-reader section!! [ 61.240228][ T21] [ 61.240228][ T21] other info that might help us debug this: [ 61.240228][ T21] [ 61.251959][ T21] [ 61.251959][ T21] rcu_scheduler_active = 2, debug_locks = 1 [ 61.260423][ T21] 3 locks held by kworker/u4:1/21: [ 61.266996][ T21] #0: ffff8880a977a138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 [ 61.279092][ T21] #1: ffffc90000dd7dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 [ 61.300535][ T21] #2: ffffffff8a5a08f0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 [ 61.309972][ T21] [ 61.309972][ T21] stack backtrace: [ 61.316576][ T21] CPU: 0 PID: 21 Comm: kworker/u4:1 Not tainted 5.7.0-rc1-next-20200417-syzkaller #0 [ 61.326049][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.336202][ T21] Workqueue: netns cleanup_net [ 61.340954][ T21] Call Trace: [ 61.344231][ T21] dump_stack+0x188/0x20d [ 61.348558][ T21] ovs_ct_exit+0x3db/0x558 [ 61.353096][ T21] ovs_exit_net+0x1df/0xba0 [ 61.357604][ T21] ? synchronize_rcu.part.0+0xda/0xf0 [ 61.362983][ T21] ? synchronize_rcu_expedited+0x620/0x620 [ 61.368920][ T21] ? ovs_dp_cmd_del+0x270/0x270 [ 61.373791][ T21] ? ovs_dp_cmd_del+0x270/0x270 [ 61.378648][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 61.383767][ T21] cleanup_net+0x511/0xa50 [ 61.388187][ T21] ? unregister_pernet_device+0x70/0x70 [ 61.393747][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.399730][ T21] ? _raw_spin_unlock_irq+0x1f/0x80 [ 61.404934][ T21] process_one_work+0x965/0x16a0 [ 61.409882][ T21] ? lock_release+0x800/0x800 [ 61.414582][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.419975][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 61.425027][ T21] worker_thread+0x96/0xe20 [ 61.429557][ T21] ? process_one_work+0x16a0/0x16a0 [ 61.434761][ T21] kthread+0x388/0x470 [ 61.438826][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.444555][ T21] ret_from_fork+0x24/0x30 [ 61.630531][ T21] tipc: TX() has been purged, node left! [ 61.672780][ T21] [ 61.675447][ T21] ============================= [ 61.680303][ T21] WARNING: suspicious RCU usage [ 61.685749][ T21] 5.7.0-rc1-next-20200417-syzkaller #0 Not tainted [ 61.693011][ T21] ----------------------------- [ 61.697941][ T21] net/ipv4/ipmr.c:1757 RCU-list traversed in non-reader section!! [ 61.706831][ T21] [ 61.706831][ T21] other info that might help us debug this: [ 61.706831][ T21] [ 61.718559][ T21] [ 61.718559][ T21] rcu_scheduler_active = 2, debug_locks = 1 [ 61.727186][ T21] 4 locks held by kworker/u4:1/21: [ 61.732837][ T21] #0: ffff8880a977a138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 [ 61.743639][ T21] #1: ffffc90000dd7dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 [ 61.754307][ T21] #2: ffffffff8a5a08f0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 [ 61.764081][ T21] #3: ffffffff8a5ac868 (rtnl_mutex){+.+.}-{3:3}, at: ip6gre_exit_batch_net+0x88/0x700 [ 61.774254][ T21] [ 61.774254][ T21] stack backtrace: [ 61.780203][ T21] CPU: 0 PID: 21 Comm: kworker/u4:1 Not tainted 5.7.0-rc1-next-20200417-syzkaller #0 [ 61.789652][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.799731][ T21] Workqueue: netns cleanup_net [ 61.804519][ T21] Call Trace: [ 61.807829][ T21] dump_stack+0x188/0x20d [ 61.812181][ T21] ipmr_device_event+0x240/0x2b0 [ 61.817125][ T21] ? __sanitizer_cov_trace_switch+0x45/0x70 [ 61.823036][ T21] notifier_call_chain+0xc0/0x230 [ 61.828089][ T21] call_netdevice_notifiers_info+0xb5/0x130 [ 61.834083][ T21] rollback_registered_many+0x75c/0xe70 [ 61.839896][ T21] ? netif_set_real_num_tx_queues+0x700/0x700 [ 61.845971][ T21] ? lock_downgrade+0x840/0x840 [ 61.850831][ T21] unregister_netdevice_many.part.0+0x16/0x1e0 [ 61.856986][ T21] unregister_netdevice_many+0x36/0x50 [ 61.862457][ T21] ip6gre_exit_batch_net+0x4e8/0x700 [ 61.867742][ T21] ? ip6gre_tunnel_link+0xf0/0xf0 [ 61.872772][ T21] ? rcu_read_lock_held_common+0x130/0x130 [ 61.878594][ T21] ? ip6gre_tunnel_link+0xf0/0xf0 [ 61.883631][ T21] ops_exit_list.isra.0+0x103/0x150 [ 61.888839][ T21] cleanup_net+0x511/0xa50 [ 61.893260][ T21] ? unregister_pernet_device+0x70/0x70 [ 61.898828][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.904812][ T21] ? _raw_spin_unlock_irq+0x1f/0x80 [ 61.910030][ T21] process_one_work+0x965/0x16a0 [ 61.914985][ T21] ? lock_release+0x800/0x800 [ 61.919666][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.925183][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 61.930133][ T21] worker_thread+0x96/0xe20 [ 61.934654][ T21] ? process_one_work+0x16a0/0x16a0 [ 61.939855][ T21] kthread+0x388/0x470 [ 61.943925][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.949652][ T21] ret_from_fork+0x24/0x30 [ 62.911383][ T6863] can: request_module (can-proto-0) failed. executing program [ 65.096432][ T6863] can: request_module (can-proto-0) failed. [ 65.108868][ T6863] can: request_module (can-proto-0) failed.