[ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Reached target Login Prompts. [ OK ] Started OpenBSD Secure Shell server. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.71' (ECDSA) to the list of known hosts. 2020/03/29 00:04:29 fuzzer started 2020/03/29 00:04:31 connecting to host at 10.128.0.26:39317 2020/03/29 00:04:31 checking machine... 2020/03/29 00:04:31 checking revisions... 2020/03/29 00:04:31 testing simple program... syzkaller login: [ 60.542485][ T7065] IPVS: ftp: loaded support on port[0] = 21 2020/03/29 00:04:32 building call list... [ 60.782404][ T970] [ 60.785391][ T970] ============================= [ 60.790245][ T970] WARNING: suspicious RCU usage [ 60.804620][ T970] 5.6.0-rc7-next-20200327-syzkaller #0 Not tainted [ 60.818673][ T970] ----------------------------- [ 60.824880][ T970] net/openvswitch/conntrack.c:1898 RCU-list traversed in non-reader section!! [ 60.834909][ T970] [ 60.834909][ T970] other info that might help us debug this: [ 60.834909][ T970] [ 60.846576][ T970] [ 60.846576][ T970] rcu_scheduler_active = 2, debug_locks = 1 [ 60.856088][ T970] 3 locks held by kworker/u4:5/970: [ 60.862301][ T970] #0: ffff8880a977e138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 [ 60.874005][ T970] #1: ffffc90003637dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 [ 60.885462][ T970] #2: ffffffff8a56cbf0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 [ 60.896247][ T970] [ 60.896247][ T970] stack backtrace: [ 60.903244][ T970] CPU: 0 PID: 970 Comm: kworker/u4:5 Not tainted 5.6.0-rc7-next-20200327-syzkaller #0 [ 60.912921][ T970] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.923106][ T970] Workqueue: netns cleanup_net [ 60.928051][ T970] Call Trace: [ 60.931370][ T970] dump_stack+0x188/0x20d [ 60.935711][ T970] ovs_ct_exit+0x3db/0x558 [ 60.940152][ T970] ovs_exit_net+0x1df/0xba0 [ 60.944685][ T970] ? synchronize_rcu.part.0+0xda/0xf0 [ 60.950074][ T970] ? synchronize_rcu_expedited+0x620/0x620 [ 60.955896][ T970] ? ovs_dp_cmd_del+0x270/0x270 [ 60.960766][ T970] ? ovs_dp_cmd_del+0x270/0x270 [ 60.965634][ T970] ops_exit_list.isra.0+0xa8/0x150 [ 60.970770][ T970] cleanup_net+0x511/0xa50 [ 60.975199][ T970] ? unregister_pernet_device+0x70/0x70 [ 60.980753][ T970] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 60.986745][ T970] ? _raw_spin_unlock_irq+0x1f/0x80 [ 60.991956][ T970] process_one_work+0x965/0x16a0 [ 60.996909][ T970] ? lock_release+0x800/0x800 [ 61.001598][ T970] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.007034][ T970] ? rwlock_bug.part.0+0x90/0x90 [ 61.011990][ T970] worker_thread+0x96/0xe20 [ 61.016517][ T970] ? process_one_work+0x16a0/0x16a0 [ 61.021725][ T970] kthread+0x388/0x470 [ 61.025802][ T970] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.031533][ T970] ret_from_fork+0x24/0x30 [ 61.260504][ T970] tipc: TX() has been purged, node left! [ 61.303576][ T970] [ 61.306029][ T970] ============================= [ 61.312265][ T970] WARNING: suspicious RCU usage [ 61.318550][ T970] 5.6.0-rc7-next-20200327-syzkaller #0 Not tainted [ 61.327544][ T970] ----------------------------- [ 61.333579][ T970] net/ipv4/ipmr.c:1757 RCU-list traversed in non-reader section!! [ 61.342570][ T970] [ 61.342570][ T970] other info that might help us debug this: [ 61.342570][ T970] [ 61.354972][ T970] [ 61.354972][ T970] rcu_scheduler_active = 2, debug_locks = 1 [ 61.364059][ T970] 4 locks held by kworker/u4:5/970: [ 61.369318][ T970] #0: ffff8880a977e138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 [ 61.381302][ T970] #1: ffffc90003637dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 [ 61.393221][ T970] #2: ffffffff8a56cbf0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 [ 61.403513][ T970] #3: ffffffff8a578ae8 (rtnl_mutex){+.+.}-{3:3}, at: ip6gre_exit_batch_net+0x88/0x700 [ 61.414086][ T970] [ 61.414086][ T970] stack backtrace: [ 61.420010][ T970] CPU: 0 PID: 970 Comm: kworker/u4:5 Not tainted 5.6.0-rc7-next-20200327-syzkaller #0 [ 61.429754][ T970] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.439965][ T970] Workqueue: netns cleanup_net [ 61.444733][ T970] Call Trace: [ 61.448051][ T970] dump_stack+0x188/0x20d [ 61.452398][ T970] ipmr_device_event+0x240/0x2b0 [ 61.457349][ T970] ? __sanitizer_cov_trace_switch+0x45/0x70 [ 61.463255][ T970] notifier_call_chain+0xc0/0x230 [ 61.468306][ T970] call_netdevice_notifiers_info+0xb5/0x130 [ 61.474208][ T970] rollback_registered_many+0x75c/0xe70 [ 61.479781][ T970] ? netif_set_real_num_tx_queues+0x700/0x700 [ 61.485866][ T970] ? lock_downgrade+0x840/0x840 [ 61.490735][ T970] unregister_netdevice_many.part.0+0x16/0x1e0 [ 61.497057][ T970] unregister_netdevice_many+0x36/0x50 [ 61.502652][ T970] ip6gre_exit_batch_net+0x4e8/0x700 [ 61.507956][ T970] ? ip6gre_tunnel_link+0xf0/0xf0 [ 61.512992][ T970] ? rcu_read_lock_held_common+0x130/0x130 [ 61.518809][ T970] ? ip6gre_tunnel_link+0xf0/0xf0 [ 61.523849][ T970] ops_exit_list.isra.0+0x103/0x150 [ 61.529063][ T970] cleanup_net+0x511/0xa50 [ 61.533517][ T970] ? unregister_pernet_device+0x70/0x70 [ 61.539075][ T970] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.545067][ T970] ? _raw_spin_unlock_irq+0x1f/0x80 [ 61.550288][ T970] process_one_work+0x965/0x16a0 [ 61.555242][ T970] ? lock_release+0x800/0x800 [ 61.559928][ T970] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.565313][ T970] ? rwlock_bug.part.0+0x90/0x90 [ 61.570268][ T970] worker_thread+0x96/0xe20 [ 61.574796][ T970] ? process_one_work+0x16a0/0x16a0 [ 61.580004][ T970] kthread+0x388/0x470 [ 61.584412][ T970] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.590152][ T970] ret_from_fork+0x24/0x30 [ 62.494895][ T7051] can: request_module (can-proto-0) failed. executing program [ 64.773596][ T7051] can: request_module (can-proto-0) failed. [ 64.786091][ T7051] can: request_module (can-proto-0) failed.