[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 73.653199][ T26] audit: type=1800 audit(1584978219.969:25): pid=9610 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 73.680623][ T26] audit: type=1800 audit(1584978219.969:26): pid=9610 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 73.723943][ T26] audit: type=1800 audit(1584978219.979:27): pid=9610 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.10.48' (ECDSA) to the list of known hosts. 2020/03/23 15:43:51 fuzzer started 2020/03/23 15:43:52 connecting to host at 10.128.0.26:35789 2020/03/23 15:43:52 checking machine... 2020/03/23 15:43:52 checking revisions... 2020/03/23 15:43:52 testing simple program... syzkaller login: [ 86.399933][ T9781] IPVS: ftp: loaded support on port[0] = 21 2020/03/23 15:43:52 building call list... [ 86.590694][ T359] [ 86.593188][ T359] ============================= [ 86.598038][ T359] WARNING: suspicious RCU usage [ 86.620127][ T359] 5.6.0-rc7-next-20200323-syzkaller #0 Not tainted [ 86.626661][ T359] ----------------------------- [ 86.640240][ T359] net/openvswitch/conntrack.c:1898 RCU-list traversed in non-reader section!! [ 86.649130][ T359] [ 86.649130][ T359] other info that might help us debug this: [ 86.649130][ T359] [ 86.660247][ T359] [ 86.660247][ T359] rcu_scheduler_active = 2, debug_locks = 1 [ 86.668353][ T359] 3 locks held by kworker/u4:5/359: [ 86.673988][ T359] #0: ffff88821b78d928 ((wq_completion)netns){+.+.}, at: process_one_work+0x82a/0x1690 [ 86.684442][ T359] #1: ffffc90001ba7dd0 (net_cleanup_work){+.+.}, at: process_one_work+0x85e/0x1690 [ 86.695277][ T359] #2: ffffffff8a55ec88 (pernet_ops_rwsem){++++}, at: cleanup_net+0x9b/0xa50 [ 86.704516][ T359] [ 86.704516][ T359] stack backtrace: [ 86.710851][ T359] CPU: 1 PID: 359 Comm: kworker/u4:5 Not tainted 5.6.0-rc7-next-20200323-syzkaller #0 [ 86.720628][ T359] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 86.730691][ T359] Workqueue: netns cleanup_net [ 86.735449][ T359] Call Trace: [ 86.738752][ T359] dump_stack+0x188/0x20d [ 86.743111][ T359] ovs_ct_exit+0x3db/0x558 [ 86.747550][ T359] ovs_exit_net+0x1df/0xba0 [ 86.752078][ T359] ? ovs_dp_cmd_del+0x270/0x270 [ 86.756946][ T359] ? __mutex_unlock_slowpath+0xe2/0x660 [ 86.762506][ T359] ? ovs_dp_cmd_del+0x270/0x270 [ 86.767362][ T359] ops_exit_list.isra.0+0xa8/0x150 [ 86.772479][ T359] cleanup_net+0x511/0xa50 [ 86.776903][ T359] ? unregister_pernet_device+0x70/0x70 [ 86.782463][ T359] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 86.788453][ T359] process_one_work+0x94b/0x1690 [ 86.793400][ T359] ? pwq_dec_nr_in_flight+0x310/0x310 [ 86.798780][ T359] ? do_raw_spin_lock+0x129/0x2e0 [ 86.803827][ T359] worker_thread+0x96/0xe20 [ 86.808353][ T359] ? process_one_work+0x1690/0x1690 [ 86.813554][ T359] kthread+0x357/0x430 [ 86.817624][ T359] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 86.823478][ T359] ret_from_fork+0x24/0x30 [ 86.990242][ T359] tipc: TX() has been purged, node left! [ 87.032442][ T359] [ 87.034888][ T359] ============================= [ 87.039745][ T359] WARNING: suspicious RCU usage [ 87.045207][ T359] 5.6.0-rc7-next-20200323-syzkaller #0 Not tainted [ 87.052315][ T359] ----------------------------- [ 87.057210][ T359] net/ipv4/ipmr.c:1757 RCU-list traversed in non-reader section!! [ 87.065701][ T359] [ 87.065701][ T359] other info that might help us debug this: [ 87.065701][ T359] [ 87.076598][ T359] [ 87.076598][ T359] rcu_scheduler_active = 2, debug_locks = 1 [ 87.086059][ T359] 4 locks held by kworker/u4:5/359: [ 87.092028][ T359] #0: ffff88821b78d928 ((wq_completion)netns){+.+.}, at: process_one_work+0x82a/0x1690 [ 87.102460][ T359] #1: ffffc90001ba7dd0 (net_cleanup_work){+.+.}, at: process_one_work+0x85e/0x1690 [ 87.112860][ T359] #2: ffffffff8a55ec88 (pernet_ops_rwsem){++++}, at: cleanup_net+0x9b/0xa50 [ 87.122288][ T359] #3: ffffffff8a56aa00 (rtnl_mutex){+.+.}, at: ip6gre_exit_batch_net+0x88/0x700 [ 87.132091][ T359] [ 87.132091][ T359] stack backtrace: [ 87.138103][ T359] CPU: 1 PID: 359 Comm: kworker/u4:5 Not tainted 5.6.0-rc7-next-20200323-syzkaller #0 [ 87.147642][ T359] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 87.157722][ T359] Workqueue: netns cleanup_net [ 87.162502][ T359] Call Trace: [ 87.165793][ T359] dump_stack+0x188/0x20d [ 87.170122][ T359] ipmr_device_event+0x240/0x2b0 [ 87.175072][ T359] ? __sanitizer_cov_trace_switch+0x45/0x70 [ 87.180964][ T359] notifier_call_chain+0xc0/0x230 [ 87.186170][ T359] call_netdevice_notifiers_info+0xb5/0x130 [ 87.192069][ T359] rollback_registered_many+0x75c/0xe70 [ 87.202153][ T359] ? netif_set_real_num_tx_queues+0x700/0x700 [ 87.208231][ T359] ? lock_downgrade+0x7f0/0x7f0 [ 87.213085][ T359] unregister_netdevice_many.part.0+0x16/0x1e0 [ 87.219238][ T359] unregister_netdevice_many+0x36/0x50 [ 87.224704][ T359] ip6gre_exit_batch_net+0x4e8/0x700 [ 87.230105][ T359] ? ip6gre_tunnel_link+0xf0/0xf0 [ 87.235127][ T359] ? rcu_read_lock_held_common+0x130/0x130 [ 87.240934][ T359] ? ip6gre_tunnel_link+0xf0/0xf0 [ 87.246107][ T359] ops_exit_list.isra.0+0x103/0x150 [ 87.251327][ T359] cleanup_net+0x511/0xa50 [ 87.256194][ T359] ? unregister_pernet_device+0x70/0x70 [ 87.261747][ T359] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 87.267740][ T359] process_one_work+0x94b/0x1690 [ 87.272712][ T359] ? pwq_dec_nr_in_flight+0x310/0x310 [ 87.278203][ T359] ? do_raw_spin_lock+0x129/0x2e0 [ 87.283249][ T359] worker_thread+0x96/0xe20 [ 87.287764][ T359] ? process_one_work+0x1690/0x1690 [ 87.293063][ T359] kthread+0x357/0x430 [ 87.297142][ T359] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 87.302867][ T359] ret_from_fork+0x24/0x30 [ 88.083400][ T9766] can: request_module (can-proto-0) failed. executing program [ 90.360737][ T9766] can: request_module (can-proto-0) failed. [ 90.373418][ T9766] can: request_module (can-proto-0) failed.