[ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. Starting Load/Save RF Kill Switch Status... [ 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. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.57' (ECDSA) to the list of known hosts. 2020/03/25 11:50:24 fuzzer started 2020/03/25 11:50:26 connecting to host at 10.128.0.26:40811 2020/03/25 11:50:26 checking machine... 2020/03/25 11:50:26 checking revisions... 2020/03/25 11:50:26 testing simple program... syzkaller login: [ 61.972042][ T7082] IPVS: ftp: loaded support on port[0] = 21 2020/03/25 11:50:26 building call list... [ 62.144629][ T267] [ 62.147111][ T267] ============================= [ 62.151959][ T267] WARNING: suspicious RCU usage [ 62.185021][ T267] 5.6.0-rc7-next-20200325-syzkaller #0 Not tainted [ 62.191549][ T267] ----------------------------- [ 62.212795][ T267] net/openvswitch/conntrack.c:1898 RCU-list traversed in non-reader section!! [ 62.227762][ T267] [ 62.227762][ T267] other info that might help us debug this: [ 62.227762][ T267] [ 62.238097][ T267] [ 62.238097][ T267] rcu_scheduler_active = 2, debug_locks = 1 [ 62.247264][ T267] 3 locks held by kworker/u4:5/267: [ 62.252648][ T267] #0: ffff8880a977b138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 [ 62.264222][ T267] #1: ffffc90001bd7dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 [ 62.284885][ T267] #2: ffffffff8a5715f0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 [ 62.295132][ T267] [ 62.295132][ T267] stack backtrace: [ 62.301809][ T267] CPU: 1 PID: 267 Comm: kworker/u4:5 Not tainted 5.6.0-rc7-next-20200325-syzkaller #0 [ 62.311341][ T267] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.321401][ T267] Workqueue: netns cleanup_net [ 62.326158][ T267] Call Trace: [ 62.329452][ T267] dump_stack+0x188/0x20d [ 62.333802][ T267] ovs_ct_exit+0x3db/0x558 [ 62.338234][ T267] ovs_exit_net+0x1df/0xba0 [ 62.342743][ T267] ? synchronize_rcu.part.0+0xda/0xf0 [ 62.348125][ T267] ? synchronize_rcu_expedited+0x620/0x620 [ 62.353944][ T267] ? ovs_dp_cmd_del+0x270/0x270 [ 62.358808][ T267] ? ovs_dp_cmd_del+0x270/0x270 [ 62.363663][ T267] ops_exit_list.isra.0+0xa8/0x150 [ 62.368814][ T267] cleanup_net+0x511/0xa50 [ 62.373250][ T267] ? unregister_pernet_device+0x70/0x70 [ 62.378803][ T267] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.384786][ T267] ? _raw_spin_unlock_irq+0x1f/0x80 [ 62.389988][ T267] process_one_work+0x965/0x16a0 [ 62.394932][ T267] ? lock_release+0x800/0x800 [ 62.399612][ T267] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.405092][ T267] ? rwlock_bug.part.0+0x90/0x90 [ 62.410056][ T267] worker_thread+0x96/0xe20 [ 62.414576][ T267] ? process_one_work+0x16a0/0x16a0 [ 62.419785][ T267] kthread+0x388/0x470 [ 62.423851][ T267] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.429568][ T267] ret_from_fork+0x24/0x30 [ 62.603396][ T267] tipc: TX() has been purged, node left! [ 62.645683][ T267] [ 62.648112][ T267] ============================= [ 62.652952][ T267] WARNING: suspicious RCU usage [ 62.659889][ T267] 5.6.0-rc7-next-20200325-syzkaller #0 Not tainted [ 62.667528][ T267] ----------------------------- [ 62.672472][ T267] net/ipv4/ipmr.c:1757 RCU-list traversed in non-reader section!! [ 62.681869][ T267] [ 62.681869][ T267] other info that might help us debug this: [ 62.681869][ T267] [ 62.693148][ T267] [ 62.693148][ T267] rcu_scheduler_active = 2, debug_locks = 1 [ 62.702239][ T267] 4 locks held by kworker/u4:5/267: [ 62.708435][ T267] #0: ffff8880a977b138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 [ 62.722089][ T267] #1: ffffc90001bd7dc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 [ 62.732873][ T267] #2: ffffffff8a5715f0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 [ 62.743117][ T267] #3: ffffffff8a57d4e8 (rtnl_mutex){+.+.}-{3:3}, at: ip6gre_exit_batch_net+0x88/0x700 [ 62.753803][ T267] [ 62.753803][ T267] stack backtrace: [ 62.759748][ T267] CPU: 1 PID: 267 Comm: kworker/u4:5 Not tainted 5.6.0-rc7-next-20200325-syzkaller #0 [ 62.769295][ T267] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.779359][ T267] Workqueue: netns cleanup_net [ 62.784113][ T267] Call Trace: [ 62.787402][ T267] dump_stack+0x188/0x20d [ 62.791741][ T267] ipmr_device_event+0x240/0x2b0 [ 62.796692][ T267] ? __sanitizer_cov_trace_switch+0x45/0x70 [ 62.802590][ T267] notifier_call_chain+0xc0/0x230 [ 62.807628][ T267] call_netdevice_notifiers_info+0xb5/0x130 [ 62.813524][ T267] rollback_registered_many+0x75c/0xe70 [ 62.819086][ T267] ? netif_set_real_num_tx_queues+0x700/0x700 [ 62.825174][ T267] ? lock_downgrade+0x840/0x840 [ 62.830055][ T267] unregister_netdevice_many.part.0+0x16/0x1e0 [ 62.836219][ T267] unregister_netdevice_many+0x36/0x50 [ 62.841671][ T267] ip6gre_exit_batch_net+0x4e8/0x700 [ 62.846984][ T267] ? ip6gre_tunnel_link+0xf0/0xf0 [ 62.852011][ T267] ? rcu_read_lock_held_common+0x130/0x130 [ 62.857817][ T267] ? ip6gre_tunnel_link+0xf0/0xf0 [ 62.862849][ T267] ops_exit_list.isra.0+0x103/0x150 [ 62.868055][ T267] cleanup_net+0x511/0xa50 [ 62.872477][ T267] ? unregister_pernet_device+0x70/0x70 [ 62.878024][ T267] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.884002][ T267] ? _raw_spin_unlock_irq+0x1f/0x80 [ 62.889298][ T267] process_one_work+0x965/0x16a0 [ 62.894245][ T267] ? lock_release+0x800/0x800 [ 62.898929][ T267] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.904314][ T267] ? rwlock_bug.part.0+0x90/0x90 [ 62.909288][ T267] worker_thread+0x96/0xe20 [ 62.913821][ T267] ? process_one_work+0x16a0/0x16a0 [ 62.919026][ T267] kthread+0x388/0x470 [ 62.923096][ T267] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.928822][ T267] ret_from_fork+0x24/0x30 [ 63.879954][ T7063] can: request_module (can-proto-0) failed. executing program [ 66.028987][ T7063] can: request_module (can-proto-0) failed. [ 66.041175][ T7063] can: request_module (can-proto-0) failed.