[ OK ] Started OpenBSD Secure Shell server. [ 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 '10.128.1.51' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 48.970799] audit: type=1400 audit(1599075384.416:8): avc: denied { execmem } for pid=6377 comm="syz-executor047" scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=process permissive=1 [ 48.992635] ip6_tables: ip6tables: counters copy to user failed while replacing table executing program [ 49.032016] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. [ 49.052939] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 49.083276] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. [ 49.100133] [ 49.101780] ====================================================== [ 49.108257] WARNING: possible circular locking dependency detected [ 49.114565] 4.14.195-syzkaller #0 Not tainted [ 49.119042] ------------------------------------------------------ [ 49.125338] syz-executor047/6387 is trying to acquire lock: [ 49.131016] (&table[i].mutex){+.+.}, at: [] nf_tables_netdev_event+0x10d/0x4d0 [ 49.140006] [ 49.140006] but task is already holding lock: [ 49.146082] (rtnl_mutex){+.+.}, at: [] rtnetlink_rcv_msg+0x31d/0xb10 [ 49.154244] [ 49.154244] which lock already depends on the new lock. [ 49.154244] [ 49.162565] [ 49.162565] the existing dependency chain (in reverse order) is: [ 49.170193] [ 49.170193] -> #2 (rtnl_mutex){+.+.}: [ 49.175450] __mutex_lock+0xc4/0x1310 [ 49.179754] unregister_netdevice_notifier+0x5e/0x2b0 [ 49.185438] tee_tg_destroy+0x5c/0xb0 [ 49.189731] cleanup_entry+0x232/0x310 [ 49.194112] __do_replace+0x38d/0x580 [ 49.198403] do_ip6t_set_ctl+0x256/0x3a4 [ 49.202955] nf_setsockopt+0x5f/0xb0 [ 49.207160] ipv6_setsockopt+0xc0/0x120 [ 49.211624] udpv6_setsockopt+0x45/0x80 [ 49.216091] SyS_setsockopt+0x110/0x1e0 [ 49.220556] do_syscall_64+0x1d5/0x640 [ 49.224955] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 49.230691] [ 49.230691] -> #1 (&xt[i].mutex){+.+.}: [ 49.236121] __mutex_lock+0xc4/0x1310 [ 49.240415] xt_find_revision+0x88/0x200 [ 49.244968] nfnl_compat_get+0x1f7/0x870 [ 49.249522] nfnetlink_rcv_msg+0x9bb/0xc00 [ 49.254283] netlink_rcv_skb+0x125/0x390 [ 49.258850] nfnetlink_rcv+0x1ab/0x1da0 [ 49.263315] netlink_unicast+0x437/0x610 [ 49.267868] netlink_sendmsg+0x62e/0xb80 [ 49.272420] sock_sendmsg+0xb5/0x100 [ 49.276661] ___sys_sendmsg+0x6c8/0x800 [ 49.281136] __sys_sendmsg+0xa3/0x120 [ 49.285427] SyS_sendmsg+0x27/0x40 [ 49.289459] do_syscall_64+0x1d5/0x640 [ 49.293872] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 49.299593] [ 49.299593] -> #0 (&table[i].mutex){+.+.}: [ 49.305286] lock_acquire+0x170/0x3f0 [ 49.309576] __mutex_lock+0xc4/0x1310 [ 49.313880] nf_tables_netdev_event+0x10d/0x4d0 [ 49.319041] notifier_call_chain+0x108/0x1a0 [ 49.323942] rollback_registered_many+0x70b/0xb30 [ 49.329275] rollback_registered+0xca/0x170 [ 49.334089] unregister_netdevice_queue+0x1b4/0x360 [ 49.339597] veth_newlink+0x52a/0x890 [ 49.343889] rtnl_newlink+0xf88/0x1830 [ 49.348269] rtnetlink_rcv_msg+0x3be/0xb10 [ 49.353018] netlink_rcv_skb+0x125/0x390 [ 49.357571] netlink_unicast+0x437/0x610 [ 49.362125] netlink_sendmsg+0x62e/0xb80 [ 49.366691] sock_sendmsg+0xb5/0x100 [ 49.370911] ___sys_sendmsg+0x6c8/0x800 [ 49.375379] __sys_sendmsg+0xa3/0x120 [ 49.379684] SyS_sendmsg+0x27/0x40 [ 49.383719] do_syscall_64+0x1d5/0x640 [ 49.388097] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 49.393790] [ 49.393790] other info that might help us debug this: [ 49.393790] [ 49.401899] Chain exists of: [ 49.401899] &table[i].mutex --> &xt[i].mutex --> rtnl_mutex [ 49.401899] [ 49.412129] Possible unsafe locking scenario: [ 49.412129] [ 49.418155] CPU0 CPU1 [ 49.422788] ---- ---- [ 49.427436] lock(rtnl_mutex); [ 49.430684] lock(&xt[i].mutex); [ 49.436623] lock(rtnl_mutex); [ 49.442389] lock(&table[i].mutex); [ 49.446072] [ 49.446072] *** DEADLOCK *** [ 49.446072] [ 49.452102] 1 lock held by syz-executor047/6387: [ 49.456827] #0: (rtnl_mutex){+.+.}, at: [] rtnetlink_rcv_msg+0x31d/0xb10 [ 49.465381] [ 49.465381] stack backtrace: [ 49.469851] CPU: 1 PID: 6387 Comm: syz-executor047 Not tainted 4.14.195-syzkaller #0 [ 49.477719] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.487049] Call Trace: [ 49.489619] dump_stack+0x1b2/0x283 [ 49.493220] print_circular_bug.constprop.0.cold+0x2d7/0x41e [ 49.498991] __lock_acquire+0x2e0e/0x3f20 [ 49.503115] ? lock_downgrade+0x740/0x740 [ 49.507235] ? unwind_next_frame+0xe54/0x17d0 [ 49.511700] ? trace_hardirqs_on+0x10/0x10 [ 49.515909] ? kernel_text_address+0xbd/0xf0 [ 49.520293] ? __kernel_text_address+0x9/0x30 [ 49.524759] ? unwind_get_return_address+0x51/0x90 [ 49.529675] lock_acquire+0x170/0x3f0 [ 49.533456] ? nf_tables_netdev_event+0x10d/0x4d0 [ 49.538270] ? nf_tables_netdev_event+0x10d/0x4d0 [ 49.543082] __mutex_lock+0xc4/0x1310 [ 49.546858] ? nf_tables_netdev_event+0x10d/0x4d0 [ 49.551680] ? nf_tables_netdev_event+0x10d/0x4d0 [ 49.556495] ? __ww_mutex_wakeup_for_backoff+0x210/0x210 [ 49.561917] ? trace_hardirqs_on+0x10/0x10 [ 49.566138] ? trace_hardirqs_on_caller+0x3a8/0x580 [ 49.571127] ? lock_downgrade+0x740/0x740 [ 49.575259] nf_tables_netdev_event+0x10d/0x4d0 [ 49.579913] ? mirred_device_event+0x12f/0x170 [ 49.584480] ? nf_tables_netdev_init_net+0x140/0x140 [ 49.589569] ? mirred_device_event+0x12f/0x170 [ 49.594123] ? __local_bh_enable_ip+0xc1/0x170 [ 49.598677] notifier_call_chain+0x108/0x1a0 [ 49.603062] rollback_registered_many+0x70b/0xb30 [ 49.607877] ? _raw_spin_unlock_irqrestore+0x79/0xe0 [ 49.612949] ? dev_set_mac_address+0x2d0/0x2d0 [ 49.617504] ? trace_hardirqs_on_caller+0x3a8/0x580 [ 49.622499] ? _raw_spin_unlock_irqrestore+0x66/0xe0 [ 49.627589] rollback_registered+0xca/0x170 [ 49.631886] ? rollback_registered_many+0xb30/0xb30 [ 49.636880] ? netdev_change_features+0xa0/0xa0 [ 49.641521] unregister_netdevice_queue+0x1b4/0x360 [ 49.646512] veth_newlink+0x52a/0x890 [ 49.650285] ? veth_close+0xb0/0xb0 [ 49.653884] ? rcu_read_lock_sched_held+0x16c/0x1d0 [ 49.658873] ? fs_reclaim_release+0xd0/0x110 [ 49.663266] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 49.668705] ? rcu_read_lock_sched_held+0x16c/0x1d0 [ 49.673692] ? __kmalloc_node+0x38/0x70 [ 49.677636] ? kmem_cache_alloc_node_trace+0x383/0x400 [ 49.682886] ? __kmalloc_node+0x4c/0x70 [ 49.686837] ? alloc_netdev_mqs+0x8c0/0xb70 [ 49.691131] ? rtnl_create_link+0x129/0x890 [ 49.695424] rtnl_newlink+0xf88/0x1830 [ 49.699283] ? rtnl_newlink+0x43d/0x1830 [ 49.703327] ? __lock_acquire+0x5fc/0x3f20 [ 49.707534] ? veth_close+0xb0/0xb0 [ 49.711131] ? trace_hardirqs_on+0x10/0x10 [ 49.715336] ? rtnl_dellink+0x6a0/0x6a0 [ 49.719281] ? trace_hardirqs_on+0x10/0x10 [ 49.723500] ? lock_acquire+0x170/0x3f0 [ 49.727467] ? lock_acquire+0x170/0x3f0 [ 49.731416] ? lock_downgrade+0x740/0x740 [ 49.735539] ? rtnl_dellink+0x6a0/0x6a0 [ 49.739496] rtnetlink_rcv_msg+0x3be/0xb10 [ 49.743705] ? rtnl_calcit.isra.0+0x3a0/0x3a0 [ 49.748186] ? __netlink_lookup+0x345/0x5d0 [ 49.752482] netlink_rcv_skb+0x125/0x390 [ 49.756519] ? rtnl_calcit.isra.0+0x3a0/0x3a0 [ 49.760986] ? netlink_ack+0x9a0/0x9a0 [ 49.764846] netlink_unicast+0x437/0x610 [ 49.768878] ? netlink_sendskb+0xd0/0xd0 [ 49.772910] netlink_sendmsg+0x62e/0xb80 [ 49.776956] ? nlmsg_notify+0x170/0x170 [ 49.780903] ? kernel_recvmsg+0x210/0x210 [ 49.785022] ? security_socket_sendmsg+0x83/0xb0 [ 49.789748] ? nlmsg_notify+0x170/0x170 [ 49.793692] sock_sendmsg+0xb5/0x100 [ 49.797377] ___sys_sendmsg+0x6c8/0x800 [ 49.801323] ? copy_msghdr_from_user+0x3b0/0x3b0 [ 49.806072] ? trace_hardirqs_on+0x10/0x10 [ 49.810287] ? trace_hardirqs_on+0x10/0x10 [ 49.814498] ? trace_hardirqs_on+0x10/0x10 [ 49.818707] ? fs_reclaim_release+0xd0/0x110 [ 49.823092] ? selinux_file_alloc_security+0xaf/0x190 [ 49.828253] ? rcu_lockdep_current_cpu_online+0xed/0x140 [ 49.833688] ? __fd_install+0x1ec/0x5c0 [ 49.837647] ? lock_acquire+0x170/0x3f0 [ 49.841593] ? lock_downgrade+0x740/0x740 [ 49.845712] ? __fdget+0x167/0x1f0 [ 49.849227] ? sockfd_lookup_light+0xb2/0x160 [ 49.853694] __sys_sendmsg+0xa3/0x120 [ 49.857522] ? SyS_shutdown+0x160/0x160 [ 49.861491] ? move_addr_to_kernel+0x60/0x60 [ 49.865879] ? __do_page_fault+0x19a/0xb50 [ 49.870091] SyS_sendmsg+0x27/0x40 [ 49.873601] ? __sys_sendmsg+0x120/0x120 [ 49.877634] do_syscall_64+0x1d5/0x640 [ 49.881499] entry_SYSCALL_64_after_hwframe+0x46/0xbb [ 49.886660] RIP: 0033:0x4416a9 [ 49.889822] RSP: 002b:00007ffd3861bc98 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 49.897505] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004416a9 [ 49.904749] RDX: 0000000000000000 RSI: 0000000020000040 RDI: 0000000000000005 [ 49.911989] RBP: 000000000000bf6e R08: 00000000004002c8 R09: 00000000004002c8 [ 49.919229] R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000402450 [ 49.926494] R13: 00000000004024e0 R14: 0000000000000000 R15: 0000000000000000 executing program executing program [ 49.987847] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 50.007529] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. executing program [ 50.058673] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 50.070683] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. executing program [ 50.117232] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 50.136175] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. executing program [ 50.177737] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 50.189881] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. [ 50.237860] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 50.254291] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. executing program executing program [ 50.307732] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 50.319746] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. executing program [ 50.367694] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 50.380233] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. [ 50.418931] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 50.430799] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. 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 executing program [ 54.006320] net_ratelimit: 69 callbacks suppressed [ 54.006323] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 54.060639] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 54.076526] nla_parse: 70 callbacks suppressed [ 54.076530] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. executing program [ 54.146361] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 54.158888] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. executing program executing program [ 54.226378] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 54.238051] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. [ 54.286523] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 54.301055] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. executing program [ 54.368567] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 54.379469] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. executing program [ 54.446408] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 54.457406] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. executing program executing program [ 54.526350] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 54.537491] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. [ 54.586284] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 54.601708] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. executing program [ 54.658339] ip6_tables: ip6tables: counters copy to user failed while replacing table [ 54.670463] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. executing program executing program [ 54.734593] netlink: 24 bytes leftover after parsing attributes in process `syz-executor047'. 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 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 [ 59.046039] net_ratelimit: 86 callbacks suppressed [ 59.046042] ip6_tables: ip6tables: counters copy to user failed while replacing table