[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 66.210779][ T26] audit: type=1800 audit(1584960534.819:25): pid=9253 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 66.258909][ T26] audit: type=1800 audit(1584960534.819:26): pid=9253 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 66.313017][ T26] audit: type=1800 audit(1584960534.819:27): pid=9253 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 '10.128.0.213' (ECDSA) to the list of known hosts. 2020/03/23 10:49:05 fuzzer started 2020/03/23 10:49:07 connecting to host at 10.128.0.26:32927 2020/03/23 10:49:07 checking machine... 2020/03/23 10:49:07 checking revisions... 2020/03/23 10:49:07 testing simple program... syzkaller login: [ 78.750773][ T9421] IPVS: ftp: loaded support on port[0] = 21 2020/03/23 10:49:07 building call list... [ 78.970536][ T150] [ 78.973028][ T150] ============================= [ 78.977885][ T150] WARNING: suspicious RCU usage [ 78.988379][ T150] 5.6.0-rc7-next-20200323-syzkaller #0 Not tainted [ 78.996794][ T150] ----------------------------- [ 79.002055][ T150] net/openvswitch/conntrack.c:1898 RCU-list traversed in non-reader section!! [ 79.011511][ T150] [ 79.011511][ T150] other info that might help us debug this: [ 79.011511][ T150] [ 79.022115][ T150] [ 79.022115][ T150] rcu_scheduler_active = 2, debug_locks = 1 [ 79.030813][ T150] 3 locks held by kworker/u4:3/150: [ 79.036021][ T150] #0: ffff88821b78d928 ((wq_completion)netns){+.+.}, at: process_one_work+0x82a/0x1690 [ 79.046205][ T150] #1: ffffc900014f7dd0 (net_cleanup_work){+.+.}, at: process_one_work+0x85e/0x1690 [ 79.056426][ T150] #2: ffffffff8a55ec88 (pernet_ops_rwsem){++++}, at: cleanup_net+0x9b/0xa50 [ 79.065617][ T150] [ 79.065617][ T150] stack backtrace: [ 79.071913][ T150] CPU: 0 PID: 150 Comm: kworker/u4:3 Not tainted 5.6.0-rc7-next-20200323-syzkaller #0 [ 79.081447][ T150] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 79.091504][ T150] Workqueue: netns cleanup_net [ 79.096258][ T150] Call Trace: [ 79.099544][ T150] dump_stack+0x188/0x20d [ 79.103874][ T150] ovs_ct_exit+0x3db/0x558 [ 79.108291][ T150] ovs_exit_net+0x1df/0xba0 [ 79.112800][ T150] ? ovs_dp_cmd_del+0x270/0x270 [ 79.117653][ T150] ? __mutex_unlock_slowpath+0xe2/0x660 [ 79.123202][ T150] ? ovs_dp_cmd_del+0x270/0x270 [ 79.128056][ T150] ops_exit_list.isra.0+0xa8/0x150 [ 79.133171][ T150] cleanup_net+0x511/0xa50 [ 79.137589][ T150] ? unregister_pernet_device+0x70/0x70 [ 79.143145][ T150] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 79.149135][ T150] process_one_work+0x94b/0x1690 [ 79.154087][ T150] ? pwq_dec_nr_in_flight+0x310/0x310 [ 79.159465][ T150] ? do_raw_spin_lock+0x129/0x2e0 [ 79.164511][ T150] worker_thread+0x96/0xe20 [ 79.169029][ T150] ? process_one_work+0x1690/0x1690 [ 79.174243][ T150] kthread+0x357/0x430 [ 79.178313][ T150] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 79.184038][ T150] ret_from_fork+0x24/0x30 [ 79.379634][ T150] tipc: TX() has been purged, node left! [ 79.430428][ T150] [ 79.432871][ T150] ============================= [ 79.437714][ T150] WARNING: suspicious RCU usage [ 79.447380][ T150] 5.6.0-rc7-next-20200323-syzkaller #0 Not tainted [ 79.454566][ T150] ----------------------------- [ 79.459473][ T150] net/ipv4/ipmr.c:1757 RCU-list traversed in non-reader section!! [ 79.467811][ T150] [ 79.467811][ T150] other info that might help us debug this: [ 79.467811][ T150] [ 79.478470][ T150] [ 79.478470][ T150] rcu_scheduler_active = 2, debug_locks = 1 [ 79.487041][ T150] 4 locks held by kworker/u4:3/150: [ 79.492623][ T150] #0: ffff88821b78d928 ((wq_completion)netns){+.+.}, at: process_one_work+0x82a/0x1690 [ 79.502964][ T150] #1: ffffc900014f7dd0 (net_cleanup_work){+.+.}, at: process_one_work+0x85e/0x1690 [ 79.512746][ T150] #2: ffffffff8a55ec88 (pernet_ops_rwsem){++++}, at: cleanup_net+0x9b/0xa50 [ 79.521891][ T150] #3: ffffffff8a56aa00 (rtnl_mutex){+.+.}, at: ip6gre_exit_batch_net+0x88/0x700 [ 79.531367][ T150] [ 79.531367][ T150] stack backtrace: [ 79.537311][ T150] CPU: 0 PID: 150 Comm: kworker/u4:3 Not tainted 5.6.0-rc7-next-20200323-syzkaller #0 [ 79.546837][ T150] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 79.556893][ T150] Workqueue: netns cleanup_net [ 79.561649][ T150] Call Trace: [ 79.564933][ T150] dump_stack+0x188/0x20d [ 79.569262][ T150] ipmr_device_event+0x240/0x2b0 [ 79.574210][ T150] ? __sanitizer_cov_trace_switch+0x45/0x70 [ 79.580108][ T150] notifier_call_chain+0xc0/0x230 [ 79.585150][ T150] call_netdevice_notifiers_info+0xb5/0x130 [ 79.591119][ T150] rollback_registered_many+0x75c/0xe70 [ 79.596666][ T150] ? netif_set_real_num_tx_queues+0x700/0x700 [ 79.602743][ T150] ? lock_downgrade+0x7f0/0x7f0 [ 79.607597][ T150] unregister_netdevice_many.part.0+0x16/0x1e0 [ 79.613755][ T150] unregister_netdevice_many+0x36/0x50 [ 79.619235][ T150] ip6gre_exit_batch_net+0x4e8/0x700 [ 79.624523][ T150] ? ip6gre_tunnel_link+0xf0/0xf0 [ 79.629557][ T150] ? rcu_read_lock_held_common+0x130/0x130 [ 79.635363][ T150] ? ip6gre_tunnel_link+0xf0/0xf0 [ 79.640399][ T150] ops_exit_list.isra.0+0x103/0x150 [ 79.645606][ T150] cleanup_net+0x511/0xa50 [ 79.650025][ T150] ? unregister_pernet_device+0x70/0x70 [ 79.655574][ T150] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 79.661562][ T150] process_one_work+0x94b/0x1690 [ 79.666514][ T150] ? pwq_dec_nr_in_flight+0x310/0x310 [ 79.671882][ T150] ? do_raw_spin_lock+0x129/0x2e0 [ 79.676912][ T150] worker_thread+0x96/0xe20 [ 79.681424][ T150] ? process_one_work+0x1690/0x1690 [ 79.686631][ T150] kthread+0x357/0x430 [ 79.690703][ T150] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 79.696425][ T150] ret_from_fork+0x24/0x30 [ 80.392316][ T9407] can: request_module (can-proto-0) failed. executing program [ 82.659366][ T9407] can: request_module (can-proto-0) failed. [ 82.671723][ T9407] can: request_module (can-proto-0) failed.