[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 82.580348][ T26] audit: type=1800 audit(1584978218.735:25): pid=9331 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 82.618526][ T26] audit: type=1800 audit(1584978218.735:26): pid=9331 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 82.652653][ T26] audit: type=1800 audit(1584978218.745:27): pid=9331 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 '10.128.0.42' (ECDSA) to the list of known hosts. 2020/03/23 15:43:48 fuzzer started 2020/03/23 15:43:49 connecting to host at 10.128.0.26:33739 2020/03/23 15:43:49 checking machine... 2020/03/23 15:43:49 checking revisions... 2020/03/23 15:43:49 testing simple program... syzkaller login: [ 93.510033][ T9498] IPVS: ftp: loaded support on port[0] = 21 2020/03/23 15:43:49 building call list... [ 93.688547][ T341] [ 93.691206][ T341] ============================= [ 93.696059][ T341] WARNING: suspicious RCU usage [ 93.707623][ T341] 5.6.0-rc7-next-20200323-syzkaller #0 Not tainted [ 93.714144][ T341] ----------------------------- [ 93.737703][ T341] net/openvswitch/conntrack.c:1898 RCU-list traversed in non-reader section!! [ 93.746655][ T341] [ 93.746655][ T341] other info that might help us debug this: [ 93.746655][ T341] [ 93.757844][ T341] [ 93.757844][ T341] rcu_scheduler_active = 2, debug_locks = 1 [ 93.765949][ T341] 3 locks held by kworker/u4:5/341: [ 93.771936][ T341] #0: ffff88821b78d928 ((wq_completion)netns){+.+.}, at: process_one_work+0x82a/0x1690 [ 93.782605][ T341] #1: ffffc900020c7dd0 (net_cleanup_work){+.+.}, at: process_one_work+0x85e/0x1690 [ 93.807717][ T341] #2: ffffffff8a55ec88 (pernet_ops_rwsem){++++}, at: cleanup_net+0x9b/0xa50 [ 93.816947][ T341] [ 93.816947][ T341] stack backtrace: [ 93.847670][ T341] CPU: 1 PID: 341 Comm: kworker/u4:5 Not tainted 5.6.0-rc7-next-20200323-syzkaller #0 [ 93.861849][ T341] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 93.872260][ T341] Workqueue: netns cleanup_net [ 93.877194][ T341] Call Trace: [ 93.880489][ T341] dump_stack+0x188/0x20d [ 93.884839][ T341] ovs_ct_exit+0x3db/0x558 [ 93.889784][ T341] ovs_exit_net+0x1df/0xba0 [ 93.894299][ T341] ? ovs_dp_cmd_del+0x270/0x270 [ 93.899406][ T341] ? __mutex_unlock_slowpath+0xe2/0x660 [ 93.904954][ T341] ? ovs_dp_cmd_del+0x270/0x270 [ 93.909803][ T341] ops_exit_list.isra.0+0xa8/0x150 [ 93.914919][ T341] cleanup_net+0x511/0xa50 [ 93.919335][ T341] ? unregister_pernet_device+0x70/0x70 [ 93.924892][ T341] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 93.930877][ T341] process_one_work+0x94b/0x1690 [ 93.936082][ T341] ? pwq_dec_nr_in_flight+0x310/0x310 [ 93.941452][ T341] ? do_raw_spin_lock+0x129/0x2e0 [ 93.946485][ T341] worker_thread+0x96/0xe20 [ 93.951258][ T341] ? process_one_work+0x1690/0x1690 [ 93.957418][ T341] kthread+0x357/0x430 [ 93.961497][ T341] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 93.967239][ T341] ret_from_fork+0x24/0x30 [ 94.147734][ T341] tipc: TX() has been purged, node left! [ 94.190000][ T341] [ 94.192530][ T341] ============================= [ 94.197377][ T341] WARNING: suspicious RCU usage [ 94.203404][ T341] 5.6.0-rc7-next-20200323-syzkaller #0 Not tainted [ 94.210353][ T341] ----------------------------- [ 94.215241][ T341] net/ipv4/ipmr.c:1757 RCU-list traversed in non-reader section!! [ 94.223392][ T341] [ 94.223392][ T341] other info that might help us debug this: [ 94.223392][ T341] [ 94.234186][ T341] [ 94.234186][ T341] rcu_scheduler_active = 2, debug_locks = 1 [ 94.243373][ T341] 4 locks held by kworker/u4:5/341: [ 94.248935][ T341] #0: ffff88821b78d928 ((wq_completion)netns){+.+.}, at: process_one_work+0x82a/0x1690 [ 94.258928][ T341] #1: ffffc900020c7dd0 (net_cleanup_work){+.+.}, at: process_one_work+0x85e/0x1690 [ 94.268647][ T341] #2: ffffffff8a55ec88 (pernet_ops_rwsem){++++}, at: cleanup_net+0x9b/0xa50 [ 94.278651][ T341] #3: ffffffff8a56aa00 (rtnl_mutex){+.+.}, at: ip6gre_exit_batch_net+0x88/0x700 [ 94.288228][ T341] [ 94.288228][ T341] stack backtrace: [ 94.294228][ T341] CPU: 0 PID: 341 Comm: kworker/u4:5 Not tainted 5.6.0-rc7-next-20200323-syzkaller #0 [ 94.303868][ T341] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 94.313952][ T341] Workqueue: netns cleanup_net [ 94.318711][ T341] Call Trace: [ 94.322016][ T341] dump_stack+0x188/0x20d [ 94.326349][ T341] ipmr_device_event+0x240/0x2b0 [ 94.331380][ T341] ? __sanitizer_cov_trace_switch+0x45/0x70 [ 94.337966][ T341] notifier_call_chain+0xc0/0x230 [ 94.343030][ T341] call_netdevice_notifiers_info+0xb5/0x130 [ 94.349043][ T341] rollback_registered_many+0x75c/0xe70 [ 94.354607][ T341] ? netif_set_real_num_tx_queues+0x700/0x700 [ 94.360780][ T341] ? lock_downgrade+0x7f0/0x7f0 [ 94.365826][ T341] unregister_netdevice_many.part.0+0x16/0x1e0 [ 94.371983][ T341] unregister_netdevice_many+0x36/0x50 [ 94.377458][ T341] ip6gre_exit_batch_net+0x4e8/0x700 [ 94.382838][ T341] ? ip6gre_tunnel_link+0xf0/0xf0 [ 94.387869][ T341] ? rcu_read_lock_held_common+0x130/0x130 [ 94.393694][ T341] ? ip6gre_tunnel_link+0xf0/0xf0 [ 94.398715][ T341] ops_exit_list.isra.0+0x103/0x150 [ 94.403913][ T341] cleanup_net+0x511/0xa50 [ 94.408423][ T341] ? unregister_pernet_device+0x70/0x70 [ 94.413969][ T341] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 94.419951][ T341] process_one_work+0x94b/0x1690 [ 94.424895][ T341] ? pwq_dec_nr_in_flight+0x310/0x310 [ 94.430266][ T341] ? do_raw_spin_lock+0x129/0x2e0 [ 94.435396][ T341] worker_thread+0x96/0xe20 [ 94.439904][ T341] ? process_one_work+0x1690/0x1690 [ 94.445098][ T341] kthread+0x357/0x430 [ 94.449162][ T341] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 94.454881][ T341] ret_from_fork+0x24/0x30 [ 95.120167][ T9480] can: request_module (can-proto-0) failed. executing program [ 97.636191][ T9480] can: request_module (can-proto-0) failed. [ 97.649289][ T9480] can: request_module (can-proto-0) failed.