[ OK ] Started Daily Cleanup of Temporary Directories. [ OK ] Reached target Timers. [ OK ] Started System Logging Service. [ OK ] Started Permit User Sessions. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. [ OK ] Started OpenBSD Secure Shell server. [ OK ] Listening on Load/Save RF Kill Switch Status /dev/rfkill Watch. [ OK ] Started Getty on tty6. [ OK ] Started Getty on tty5. [ OK ] Started Getty on tty4. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.134' (ECDSA) to the list of known hosts. 2020/03/30 12:14:04 fuzzer started 2020/03/30 12:14:06 connecting to host at 10.128.0.26:37465 2020/03/30 12:14:06 checking machine... 2020/03/30 12:14:06 checking revisions... 2020/03/30 12:14:06 testing simple program... syzkaller login: [ 66.910418][ T7068] IPVS: ftp: loaded support on port[0] = 21 2020/03/30 12:14:07 building call list... [ 67.128339][ T7] [ 67.130843][ T7] ============================= [ 67.140444][ T7] WARNING: suspicious RCU usage [ 67.148311][ T7] 5.6.0-rc7-next-20200330-syzkaller #0 Not tainted [ 67.154862][ T7] ----------------------------- [ 67.177326][ T7] net/openvswitch/conntrack.c:1898 RCU-list traversed in non-reader section!! [ 67.186213][ T7] [ 67.186213][ T7] other info that might help us debug this: [ 67.186213][ T7] [ 67.198513][ T7] [ 67.198513][ T7] rcu_scheduler_active = 2, debug_locks = 1 [ 67.206631][ T7] 3 locks held by kworker/u4:0/7: [ 67.213100][ T7] #0: ffff8880a977e138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 [ 67.224438][ T7] #1: ffffc90000cdfdc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 [ 67.235492][ T7] #2: ffffffff8a56ed30 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 [ 67.245838][ T7] [ 67.245838][ T7] stack backtrace: [ 67.252684][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.6.0-rc7-next-20200330-syzkaller #0 [ 67.262063][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 67.272214][ T7] Workqueue: netns cleanup_net [ 67.276971][ T7] Call Trace: [ 67.280263][ T7] dump_stack+0x188/0x20d [ 67.284612][ T7] ovs_ct_exit+0x3db/0x558 [ 67.289046][ T7] ovs_exit_net+0x1df/0xba0 [ 67.293559][ T7] ? synchronize_rcu.part.0+0xda/0xf0 [ 67.298947][ T7] ? synchronize_rcu_expedited+0x620/0x620 [ 67.304771][ T7] ? ovs_dp_cmd_del+0x270/0x270 [ 67.309636][ T7] ? ovs_dp_cmd_del+0x270/0x270 [ 67.315016][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 67.320140][ T7] cleanup_net+0x511/0xa50 [ 67.324568][ T7] ? unregister_pernet_device+0x70/0x70 [ 67.330120][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 67.336106][ T7] ? _raw_spin_unlock_irq+0x1f/0x80 [ 67.341321][ T7] process_one_work+0x965/0x16a0 [ 67.346277][ T7] ? lock_release+0x800/0x800 [ 67.350965][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 67.356442][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 67.361396][ T7] worker_thread+0x96/0xe20 [ 67.365928][ T7] ? process_one_work+0x16a0/0x16a0 [ 67.371135][ T7] kthread+0x388/0x470 [ 67.375207][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 67.380932][ T7] ret_from_fork+0x24/0x30 [ 67.567066][ T7] tipc: TX() has been purged, node left! [ 67.619404][ T7] [ 67.621856][ T7] ============================= [ 67.626698][ T7] WARNING: suspicious RCU usage [ 67.633529][ T7] 5.6.0-rc7-next-20200330-syzkaller #0 Not tainted [ 67.641190][ T7] ----------------------------- [ 67.646086][ T7] net/ipv4/ipmr.c:1757 RCU-list traversed in non-reader section!! [ 67.655464][ T7] [ 67.655464][ T7] other info that might help us debug this: [ 67.655464][ T7] [ 67.666676][ T7] [ 67.666676][ T7] rcu_scheduler_active = 2, debug_locks = 1 [ 67.675962][ T7] 4 locks held by kworker/u4:0/7: [ 67.681961][ T7] #0: ffff8880a977e138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x844/0x16a0 [ 67.693398][ T7] #1: ffffc90000cdfdc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x878/0x16a0 [ 67.704256][ T7] #2: ffffffff8a56ed30 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xa50 [ 67.714697][ T7] #3: ffffffff8a57aca8 (rtnl_mutex){+.+.}-{3:3}, at: ip6gre_exit_batch_net+0x88/0x700 [ 67.725436][ T7] [ 67.725436][ T7] stack backtrace: [ 67.732440][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.6.0-rc7-next-20200330-syzkaller #0 [ 67.741826][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 67.751895][ T7] Workqueue: netns cleanup_net [ 67.756654][ T7] Call Trace: [ 67.759944][ T7] dump_stack+0x188/0x20d [ 67.764288][ T7] ipmr_device_event+0x240/0x2b0 [ 67.769246][ T7] ? __sanitizer_cov_trace_switch+0x45/0x70 [ 67.775155][ T7] notifier_call_chain+0xc0/0x230 [ 67.780205][ T7] call_netdevice_notifiers_info+0xb5/0x130 [ 67.786102][ T7] rollback_registered_many+0x75c/0xe70 [ 67.791772][ T7] ? netif_set_real_num_tx_queues+0x700/0x700 [ 67.797857][ T7] ? lock_downgrade+0x840/0x840 [ 67.802740][ T7] unregister_netdevice_many.part.0+0x16/0x1e0 [ 67.808897][ T7] unregister_netdevice_many+0x36/0x50 [ 67.814358][ T7] ip6gre_exit_batch_net+0x4e8/0x700 [ 67.819662][ T7] ? ip6gre_tunnel_link+0xf0/0xf0 [ 67.824866][ T7] ? rcu_read_lock_held_common+0x130/0x130 [ 67.830683][ T7] ? ip6gre_tunnel_link+0xf0/0xf0 [ 67.835698][ T7] ops_exit_list.isra.0+0x103/0x150 [ 67.840894][ T7] cleanup_net+0x511/0xa50 [ 67.845317][ T7] ? unregister_pernet_device+0x70/0x70 [ 67.850877][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 67.856875][ T7] ? _raw_spin_unlock_irq+0x1f/0x80 [ 67.862083][ T7] process_one_work+0x965/0x16a0 [ 67.867038][ T7] ? lock_release+0x800/0x800 [ 67.871717][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 67.877098][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 67.882047][ T7] worker_thread+0x96/0xe20 [ 67.886568][ T7] ? process_one_work+0x16a0/0x16a0 [ 67.891770][ T7] kthread+0x388/0x470 [ 67.895846][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 67.901570][ T7] ret_from_fork+0x24/0x30 [ 68.896819][ T7056] can: request_module (can-proto-0) failed. executing program [ 71.083046][ T7056] can: request_module (can-proto-0) failed. [ 71.095333][ T7056] can: request_module (can-proto-0) failed.