[ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.27' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program syzkaller login: [ 38.523588] audit: type=1400 audit(1597210694.444:8): avc: denied { execmem } for pid=6366 comm="syz-executor192" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 [ 38.546247] IPVS: ftp: loaded support on port[0] = 21 [ 38.578841] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 38.589023] IPVS: ftp: loaded support on port[0] = 21 [ 38.590807] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 38.609915] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program executing program [ 38.632042] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 38.646715] IPVS: ftp: loaded support on port[0] = 21 [ 38.650628] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 38.661538] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program [ 38.708768] IPVS: ftp: loaded support on port[0] = 21 [ 38.716736] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 38.738941] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program executing program [ 38.776555] IPVS: ftp: loaded support on port[0] = 21 [ 38.786500] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program executing program [ 38.832160] IPVS: ftp: loaded support on port[0] = 21 [ 38.846699] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 38.900346] IPVS: ftp: loaded support on port[0] = 21 executing program executing program [ 38.950540] IPVS: ftp: loaded support on port[0] = 21 executing program executing program [ 39.002536] IPVS: ftp: loaded support on port[0] = 21 executing program executing program [ 39.099410] [ 39.101067] ====================================================== [ 39.107422] WARNING: possible circular locking dependency detected [ 39.113734] 4.14.193-syzkaller #0 Not tainted [ 39.118201] ------------------------------------------------------ [ 39.124556] kworker/u4:0/5 is trying to acquire lock: [ 39.129775] (&table[i].mutex){+.+.}, at: [] nf_tables_netdev_event+0x10d/0x4d0 [ 39.138860] [ 39.138860] but task is already holding lock: [ 39.144809] (rtnl_mutex){+.+.}, at: [] ip6gre_exit_net+0x70/0x570 [ 39.152860] [ 39.152860] which lock already depends on the new lock. [ 39.152860] [ 39.161162] [ 39.161162] the existing dependency chain (in reverse order) is: [ 39.169368] [ 39.169368] -> #2 (rtnl_mutex){+.+.}: [ 39.174646] __mutex_lock+0xc4/0x1310 [ 39.178951] unregister_netdevice_notifier+0x5e/0x2b0 [ 39.184696] tee_tg_destroy+0x5c/0xb0 [ 39.188996] cleanup_entry+0x232/0x310 [ 39.193389] __do_replace+0x38d/0x580 [ 39.197771] do_ip6t_set_ctl+0x256/0x3a4 [ 39.202343] nf_setsockopt+0x5f/0xb0 [ 39.206562] ipv6_setsockopt+0xc0/0x120 [ 39.211050] udpv6_setsockopt+0x45/0x80 [ 39.215523] SyS_setsockopt+0x110/0x1e0 [ 39.220089] do_syscall_64+0x1d5/0x640 [ 39.224472] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 39.230173] [ 39.230173] -> #1 (&xt[i].mutex){+.+.}: [ 39.235618] __mutex_lock+0xc4/0x1310 [ 39.239920] xt_find_revision+0x88/0x200 [ 39.244517] nfnl_compat_get+0x1f7/0x870 [ 39.249085] nfnetlink_rcv_msg+0x9bb/0xc00 [ 39.253836] netlink_rcv_skb+0x125/0x390 [ 39.258400] nfnetlink_rcv+0x1ab/0x1da0 [ 39.262929] netlink_unicast+0x437/0x610 [ 39.267492] netlink_sendmsg+0x62e/0xb80 [ 39.272058] sock_sendmsg+0xb5/0x100 [ 39.276274] ___sys_sendmsg+0x6c8/0x800 [ 39.280755] __sys_sendmsg+0xa3/0x120 [ 39.285058] SyS_sendmsg+0x27/0x40 [ 39.289120] do_syscall_64+0x1d5/0x640 [ 39.293553] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 39.299251] [ 39.299251] -> #0 (&table[i].mutex){+.+.}: [ 39.304958] lock_acquire+0x170/0x3f0 [ 39.309260] __mutex_lock+0xc4/0x1310 [ 39.313564] nf_tables_netdev_event+0x10d/0x4d0 [ 39.318827] notifier_call_chain+0x108/0x1a0 [ 39.324267] rollback_registered_many+0x70b/0xb30 [ 39.329611] unregister_netdevice_many.part.0+0x18/0x2e0 [ 39.335557] unregister_netdevice_many+0x36/0x50 [ 39.340815] ip6gre_exit_net+0x41e/0x570 [ 39.345375] ops_exit_list+0xa5/0x150 [ 39.349675] cleanup_net+0x3b3/0x840 [ 39.353894] process_one_work+0x793/0x14a0 [ 39.358625] worker_thread+0x5cc/0xff0 [ 39.363550] kthread+0x30d/0x420 [ 39.367437] ret_from_fork+0x24/0x30 [ 39.371646] [ 39.371646] other info that might help us debug this: [ 39.371646] [ 39.379771] Chain exists of: [ 39.379771] &table[i].mutex --> &xt[i].mutex --> rtnl_mutex [ 39.379771] [ 39.389976] Possible unsafe locking scenario: [ 39.389976] [ 39.396005] CPU0 CPU1 [ 39.400650] ---- ---- [ 39.405288] lock(rtnl_mutex); [ 39.408576] lock(&xt[i].mutex); [ 39.414520] lock(rtnl_mutex); [ 39.420309] lock(&table[i].mutex); [ 39.424016] [ 39.424016] *** DEADLOCK *** [ 39.424016] [ 39.430048] 4 locks held by kworker/u4:0/5: [ 39.434340] #0: ("%s""netns"){+.+.}, at: [] process_one_work+0x6b0/0x14a0 [ 39.443010] #1: (net_cleanup_work){+.+.}, at: [] process_one_work+0x6e6/0x14a0 [ 39.452089] #2: (net_mutex){+.+.}, at: [] cleanup_net+0x110/0x840 [ 39.460041] #3: (rtnl_mutex){+.+.}, at: [] ip6gre_exit_net+0x70/0x570 [ 39.468338] [ 39.468338] stack backtrace: [ 39.472809] CPU: 1 PID: 5 Comm: kworker/u4:0 Not tainted 4.14.193-syzkaller #0 [ 39.480148] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 39.489502] Workqueue: netns cleanup_net [ 39.493569] Call Trace: [ 39.496154] dump_stack+0x1b2/0x283 [ 39.499779] print_circular_bug.constprop.0.cold+0x2d7/0x41e [ 39.505557] __lock_acquire+0x2e0e/0x3f20 [ 39.509680] ? unwind_next_frame+0x404/0x17d0 [ 39.514150] ? trace_hardirqs_on+0x10/0x10 [ 39.518360] ? check_usage_forwards+0x2d0/0x2d0 [ 39.523025] ? ret_from_fork+0x24/0x30 [ 39.526910] lock_acquire+0x170/0x3f0 [ 39.530688] ? nf_tables_netdev_event+0x10d/0x4d0 [ 39.535504] ? nf_tables_netdev_event+0x10d/0x4d0 [ 39.540320] __mutex_lock+0xc4/0x1310 [ 39.544119] ? nf_tables_netdev_event+0x10d/0x4d0 [ 39.548944] ? nf_tables_netdev_event+0x10d/0x4d0 [ 39.553762] ? __ww_mutex_wakeup_for_backoff+0x210/0x210 [ 39.559211] ? trace_hardirqs_on+0x10/0x10 [ 39.563423] ? trace_hardirqs_on_caller+0x3a8/0x580 [ 39.568437] ? lock_downgrade+0x740/0x740 [ 39.572565] nf_tables_netdev_event+0x10d/0x4d0 [ 39.577210] ? mirred_device_event+0x12f/0x170 [ 39.581788] ? nf_tables_netdev_init_net+0x140/0x140 [ 39.586893] ? mirred_device_event+0x12f/0x170 [ 39.591450] ? __local_bh_enable_ip+0xc1/0x170 [ 39.596013] notifier_call_chain+0x108/0x1a0 [ 39.600404] rollback_registered_many+0x70b/0xb30 [ 39.605223] ? __ww_mutex_wakeup_for_backoff+0x210/0x210 [ 39.610647] ? dev_set_mac_address+0x2d0/0x2d0 [ 39.615204] ? lock_acquire+0x170/0x3f0 [ 39.619152] unregister_netdevice_many.part.0+0x18/0x2e0 [ 39.624593] unregister_netdevice_many+0x36/0x50 [ 39.629326] ip6gre_exit_net+0x41e/0x570 [ 39.633367] ? lock_downgrade+0x740/0x740 [ 39.637505] ? ip6gre_dellink+0x260/0x260 [ 39.641650] ? ip6gre_dellink+0x260/0x260 [ 39.645775] ops_exit_list+0xa5/0x150 [ 39.649571] cleanup_net+0x3b3/0x840 [ 39.653268] ? net_drop_ns+0x70/0x70 [ 39.656957] ? lock_acquire+0x170/0x3f0 [ 39.660906] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 39.666333] process_one_work+0x793/0x14a0 [ 39.670547] ? work_busy+0x320/0x320 [ 39.674235] ? worker_thread+0x158/0xff0 [ 39.678272] ? _raw_spin_unlock_irq+0x24/0x80 [ 39.687266] worker_thread+0x5cc/0xff0 [ 39.691131] ? rescuer_thread+0xc80/0xc80 [ 39.695776] kthread+0x30d/0x420 executing program executing program executing program executing program [ 39.699117] ? kthread_create_on_node+0xd0/0xd0 [ 39.703761] ret_from_fork+0x24/0x30 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 40.308389] IPVS: ftp: loaded support on port[0] = 21 executing program executing program [ 40.350933] IPVS: ftp: loaded support on port[0] = 21 executing program executing program [ 40.391742] IPVS: ftp: loaded support on port[0] = 21 [ 40.440378] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 42.298603] IPVS: ftp: loaded support on port[0] = 21 executing program [ 42.343172] IPVS: ftp: loaded support on port[0] = 21 executing program [ 42.380704] IPVS: ftp: loaded support on port[0] = 21 executing program [ 42.425929] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 43.535174] IPVS: ftp: loaded support on port[0] = 21 executing program [ 43.577968] IPVS: ftp: loaded support on port[0] = 21 executing program executing program [ 43.622016] IPVS: ftp: loaded support on port[0] = 21 [ 43.629235] net_ratelimit: 144 callbacks suppressed [ 43.629238] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program [ 43.664458] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 43.682408] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 43.692360] IPVS: ftp: loaded support on port[0] = 21 [ 43.697925] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program executing program executing program [ 43.755679] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 43.795506] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program executing program [ 43.854515] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 43.872533] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 43.883609] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program [ 43.899414] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 45.250007] IPVS: ftp: loaded support on port[0] = 21 [ 45.289574] IPVS: ftp: loaded support on port[0] = 21 executing program [ 45.335553] IPVS: ftp: loaded support on port[0] = 21 executing program executing program [ 45.378148] IPVS: ftp: loaded support on port[0] = 21 executing program [ 45.424599] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 47.369027] IPVS: ftp: loaded support on port[0] = 21 executing program [ 47.420276] IPVS: ftp: loaded support on port[0] = 21 executing program [ 47.464153] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program [ 47.507354] IPVS: ftp: loaded support on port[0] = 21 executing program [ 47.559304] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 48.639652] net_ratelimit: 165 callbacks suppressed [ 48.639654] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 48.662649] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 48.672687] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program executing program [ 48.729508] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 48.756503] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 48.766450] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program executing program executing program executing program [ 48.842395] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 48.851820] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 48.866034] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 48.911645] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program executing program executing program executing program executing program executing program