[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 96.301726][ T26] audit: type=1800 audit(1585039340.246:25): pid=9674 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 96.334956][ T26] audit: type=1800 audit(1585039340.256:26): pid=9674 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 96.374372][ T26] audit: type=1800 audit(1585039340.256:27): pid=9674 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 '10.128.10.16' (ECDSA) to the list of known hosts. 2020/03/24 08:42:32 fuzzer started 2020/03/24 08:42:33 connecting to host at 10.128.0.26:36389 2020/03/24 08:42:33 checking machine... 2020/03/24 08:42:33 checking revisions... 2020/03/24 08:42:33 testing simple program... syzkaller login: [ 110.068229][ T9844] IPVS: ftp: loaded support on port[0] = 21 2020/03/24 08:42:34 building call list... [ 110.255877][ T7] [ 110.258651][ T7] ============================= [ 110.275222][ T7] WARNING: suspicious RCU usage [ 110.283037][ T7] 5.6.0-rc7-next-20200324-syzkaller #0 Not tainted [ 110.298366][ T7] ----------------------------- [ 110.306316][ T7] net/openvswitch/conntrack.c:1898 RCU-list traversed in non-reader section!! [ 110.315509][ T7] [ 110.315509][ T7] other info that might help us debug this: [ 110.315509][ T7] [ 110.326024][ T7] [ 110.326024][ T7] rcu_scheduler_active = 2, debug_locks = 1 [ 110.334159][ T7] 3 locks held by kworker/u4:0/7: [ 110.339450][ T7] #0: ffff88821b78d928 ((wq_completion)netns){+.+.}, at: process_one_work+0x82a/0x1690 [ 110.349501][ T7] #1: ffffc90000cdfdd0 (net_cleanup_work){+.+.}, at: process_one_work+0x85e/0x1690 [ 110.359556][ T7] #2: ffffffff8a55f388 (pernet_ops_rwsem){++++}, at: cleanup_net+0x9b/0xa50 [ 110.368840][ T7] [ 110.368840][ T7] stack backtrace: [ 110.374800][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.6.0-rc7-next-20200324-syzkaller #0 [ 110.384162][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 110.394226][ T7] Workqueue: netns cleanup_net [ 110.398983][ T7] Call Trace: [ 110.402276][ T7] dump_stack+0x188/0x20d [ 110.406609][ T7] ovs_ct_exit+0x3db/0x558 [ 110.411034][ T7] ovs_exit_net+0x1df/0xba0 [ 110.415895][ T7] ? ovs_dp_cmd_del+0x270/0x270 [ 110.420742][ T7] ? __mutex_unlock_slowpath+0xe2/0x660 [ 110.426294][ T7] ? ovs_dp_cmd_del+0x270/0x270 [ 110.431147][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 110.436257][ T7] cleanup_net+0x511/0xa50 [ 110.440686][ T7] ? unregister_pernet_device+0x70/0x70 [ 110.446249][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 110.452251][ T7] process_one_work+0x94b/0x1690 [ 110.457211][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 110.462591][ T7] ? do_raw_spin_lock+0x129/0x2e0 [ 110.467638][ T7] worker_thread+0x96/0xe20 [ 110.472157][ T7] ? process_one_work+0x1690/0x1690 [ 110.477362][ T7] kthread+0x357/0x430 [ 110.481433][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 110.487153][ T7] ret_from_fork+0x24/0x30 [ 110.664997][ T7] tipc: TX() has been purged, node left! [ 110.706959][ T7] [ 110.709425][ T7] ============================= [ 110.714273][ T7] WARNING: suspicious RCU usage [ 110.719766][ T7] 5.6.0-rc7-next-20200324-syzkaller #0 Not tainted [ 110.726707][ T7] ----------------------------- [ 110.731623][ T7] net/ipv4/ipmr.c:1757 RCU-list traversed in non-reader section!! [ 110.740101][ T7] [ 110.740101][ T7] other info that might help us debug this: [ 110.740101][ T7] [ 110.750858][ T7] [ 110.750858][ T7] rcu_scheduler_active = 2, debug_locks = 1 [ 110.759318][ T7] 4 locks held by kworker/u4:0/7: [ 110.764399][ T7] #0: ffff88821b78d928 ((wq_completion)netns){+.+.}, at: process_one_work+0x82a/0x1690 [ 110.774650][ T7] #1: ffffc90000cdfdd0 (net_cleanup_work){+.+.}, at: process_one_work+0x85e/0x1690 [ 110.784636][ T7] #2: ffffffff8a55f388 (pernet_ops_rwsem){++++}, at: cleanup_net+0x9b/0xa50 [ 110.793850][ T7] #3: ffffffff8a56b100 (rtnl_mutex){+.+.}, at: ip6gre_exit_batch_net+0x88/0x700 [ 110.803408][ T7] [ 110.803408][ T7] stack backtrace: [ 110.810038][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.6.0-rc7-next-20200324-syzkaller #0 [ 110.819411][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 110.829466][ T7] Workqueue: netns cleanup_net [ 110.834219][ T7] Call Trace: [ 110.837519][ T7] dump_stack+0x188/0x20d [ 110.841866][ T7] ipmr_device_event+0x240/0x2b0 [ 110.846826][ T7] ? __sanitizer_cov_trace_switch+0x45/0x70 [ 110.852734][ T7] notifier_call_chain+0xc0/0x230 [ 110.857856][ T7] call_netdevice_notifiers_info+0xb5/0x130 [ 110.863747][ T7] rollback_registered_many+0x75c/0xe70 [ 110.869297][ T7] ? netif_set_real_num_tx_queues+0x700/0x700 [ 110.875375][ T7] ? lock_downgrade+0x7f0/0x7f0 [ 110.880233][ T7] unregister_netdevice_many.part.0+0x16/0x1e0 [ 110.886397][ T7] unregister_netdevice_many+0x36/0x50 [ 110.891857][ T7] ip6gre_exit_batch_net+0x4e8/0x700 [ 110.897148][ T7] ? ip6gre_tunnel_link+0xf0/0xf0 [ 110.902172][ T7] ? rcu_read_lock_held_common+0x130/0x130 [ 110.907985][ T7] ? ip6gre_tunnel_link+0xf0/0xf0 [ 110.913010][ T7] ops_exit_list.isra.0+0x103/0x150 [ 110.918213][ T7] cleanup_net+0x511/0xa50 [ 110.922632][ T7] ? unregister_pernet_device+0x70/0x70 [ 110.928196][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 110.934178][ T7] process_one_work+0x94b/0x1690 [ 110.939127][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 110.944516][ T7] ? do_raw_spin_lock+0x129/0x2e0 [ 110.949557][ T7] worker_thread+0x96/0xe20 [ 110.954155][ T7] ? process_one_work+0x1690/0x1690 [ 110.959366][ T7] kthread+0x357/0x430 [ 110.963443][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 110.969167][ T7] ret_from_fork+0x24/0x30 [ 111.887452][ T9829] can: request_module (can-proto-0) failed. executing program [ 113.993858][ T9829] can: request_module (can-proto-0) failed. [ 114.006329][ T9829] can: request_module (can-proto-0) failed.