INIT: Entering runlevel: 2 [info] Using makefile-style concurrent boot in runlevel 2. [....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] 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 '10.128.0.43' (ECDSA) to the list of known hosts. 2018/04/12 05:06:08 parsed 1 programs 2018/04/12 05:06:08 executed programs: 0 syzkaller login: [ 28.693165] IPVS: ftp: loaded support on port[0] = 21 [ 28.735115] IPVS: ftp: loaded support on port[0] = 21 [ 28.770754] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.770881] IPVS: stopping backup sync thread 4502 ... [ 28.790320] IPVS: ftp: loaded support on port[0] = 21 [ 28.792088] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.795729] IPVS: stopping backup sync thread 4504 ... [ 28.819729] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.826302] IPVS: stopping backup sync thread 4508 ... [ 28.852479] IPVS: ftp: loaded support on port[0] = 21 [ 28.864864] IPVS: stopping backup sync thread 4513 ... [ 28.866062] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.870732] IPVS: stopping backup sync thread 4514 ... [ 28.888133] IPVS: stopping backup sync thread 4517 ... [ 28.890615] IPVS: stopping backup sync thread 4520 ... [ 28.912531] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.940080] IPVS: stopping backup sync thread 4532 ... [ 28.945542] IPVS: stopping backup sync thread 4522 ... [ 28.962682] IPVS: ftp: loaded support on port[0] = 21 [ 28.971746] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.972366] IPVS: stopping backup sync thread 4535 ... [ 28.998353] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.010009] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.023168] IPVS: stopping backup sync thread 4536 ... [ 29.023203] IPVS: stopping backup sync thread 4546 ... [ 29.043215] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.054840] IPVS: stopping backup sync thread 4552 ... [ 29.060252] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.070156] IPVS: stopping backup sync thread 4541 ... [ 29.077788] IPVS: stopping backup sync thread 4547 ... [ 29.087752] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.103853] IPVS: stopping backup sync thread 4559 ... [ 29.108452] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.119754] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.130543] IPVS: ftp: loaded support on port[0] = 21 [ 29.139346] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.140232] IPVS: stopping backup sync thread 4568 ... [ 29.157094] IPVS: stopping backup sync thread 4557 ... [ 29.163366] IPVS: stopping backup sync thread 4567 ... [ 29.178559] IPVS: stopping backup sync thread 4574 ... [ 29.188140] IPVS: stopping backup sync thread 4577 ... [ 29.193549] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.210715] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.219587] IPVS: stopping backup sync thread 4586 ... [ 29.248118] IPVS: stopping backup sync thread 4591 ... [ 29.251098] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.271157] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.279854] IPVS: stopping backup sync thread 4596 ... [ 29.306801] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.307582] IPVS: ftp: loaded support on port[0] = 21 [ 29.337935] IPVS: stopping backup sync thread 4600 ... [ 29.337937] IPVS: stopping backup sync thread 4604 ... [ 29.349129] IPVS: stopping backup sync thread 4609 ... [ 29.349578] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.371718] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.391095] IPVS: ftp: loaded support on port[0] = 21 [ 29.417152] IPVS: stopping backup sync thread 4617 ... [ 29.422043] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.437311] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.469066] IPVS: stopping backup sync thread 4624 ... [ 29.475890] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.476060] IPVS: stopping backup sync thread 4626 ... [ 29.501227] IPVS: stopping backup sync thread 4587 ... [ 29.501652] IPVS: stopping backup sync thread 4580 ... [ 29.508541] IPVS: stopping backup sync thread 4619 ... [ 29.513416] IPVS: stopping backup sync thread 4611 ... [ 29.526090] IPVS: stopping backup sync thread 4641 ... [ 29.532592] IPVS: stopping backup sync thread 4645 ... [ 29.534329] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.547460] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.547505] IPVS: stopping backup sync thread 4650 ... [ 29.561766] IPVS: stopping backup sync thread 4581 ... [ 29.566289] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.567335] IPVS: stopping backup sync thread 4653 ... [ 29.581727] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.583110] IPVS: stopping backup sync thread 4654 ... [ 29.593247] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.599408] IPVS: stopping backup sync thread 4656 ... [ 29.612198] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.624557] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.633555] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 29.642492] [ 29.644113] ============================================ [ 29.649608] WARNING: possible recursive locking detected [ 29.655044] 4.16.0+ #288 Not tainted [ 29.658744] -------------------------------------------- [ 29.664268] syz-executor6/4638 is trying to acquire lock: [ 29.669785] 000000005d1b27dc (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 29.676629] [ 29.676629] but task is already holding lock: [ 29.682590] 000000005d1b27dc (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 29.689434] [ 29.689434] other info that might help us debug this: [ 29.696073] Possible unsafe locking scenario: [ 29.696073] [ 29.702110] CPU0 [ 29.704668] ---- [ 29.707222] lock(rtnl_mutex); [ 29.710481] lock(rtnl_mutex); [ 29.713741] [ 29.713741] *** DEADLOCK *** [ 29.713741] [ 29.719865] May be due to missing lock nesting notation [ 29.719865] [ 29.726775] 2 locks held by syz-executor6/4638: [ 29.731417] #0: 000000005d1b27dc (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 29.738684] #1: 00000000368a05eb (ipvs->sync_mutex){+.+.}, at: do_ip_vs_set_ctl+0x10f8/0x1cc0 [ 29.747418] [ 29.747418] stack backtrace: [ 29.751891] CPU: 0 PID: 4638 Comm: syz-executor6 Not tainted 4.16.0+ #288 [ 29.759316] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.768664] Call Trace: [ 29.771236] dump_stack+0x1a7/0x27d [ 29.774843] ? arch_local_irq_restore+0x53/0x53 [ 29.779497] ? print_lock+0xd7/0xdc [ 29.783118] __lock_acquire+0xf03/0x3c30 [ 29.787174] ? select_task_rq_fair+0xcac/0x3620 [ 29.791829] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 29.797001] ? __enqueue_entity+0x109/0x1e0 [ 29.808352] ? __lock_acquire+0x638/0x3c30 [ 29.812575] ? update_curr+0x332/0xae0 [ 29.816460] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 29.821636] ? __lock_acquire+0x638/0x3c30 [ 29.825853] ? trace_hardirqs_off+0x10/0x10 [ 29.830154] ? trace_hardirqs_off+0x10/0x10 [ 29.834452] ? trace_hardirqs_off+0x10/0x10 [ 29.838748] ? trace_hardirqs_off+0x10/0x10 [ 29.843051] ? dequeue_task_fair+0x9b0/0x9b0 [ 29.847444] lock_acquire+0x1d5/0x580 [ 29.851229] ? lock_acquire+0x1d5/0x580 [ 29.855186] ? rtnl_lock+0x17/0x20 [ 29.858724] ? lock_release+0xa40/0xa40 [ 29.862674] ? check_same_owner+0x320/0x320 [ 29.866983] ? rcu_note_context_switch+0x710/0x710 [ 29.871891] ? __might_sleep+0x95/0x190 [ 29.875858] ? rtnl_lock+0x17/0x20 [ 29.879375] __mutex_lock+0x16d/0x1810 [ 29.883247] ? rtnl_lock+0x17/0x20 [ 29.886764] ? wait_for_completion_killable+0x63e/0x820 [ 29.892103] ? rtnl_lock+0x17/0x20 [ 29.895619] ? lock_downgrade+0x980/0x980 [ 29.899742] ? lock_release+0xa40/0xa40 [ 29.903696] ? mutex_lock_io_nested+0x16c0/0x16c0 [ 29.908515] ? mark_held_locks+0xaf/0x100 [ 29.912646] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.917122] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 29.922119] ? trace_hardirqs_on+0xd/0x10 [ 29.926263] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.930745] ? wait_for_completion_killable+0x63e/0x820 [ 29.936099] ? wait_for_completion_interruptible_timeout+0x820/0x820 [ 29.942568] ? lock_downgrade+0x980/0x980 [ 29.946692] ? lock_release+0xa40/0xa40 [ 29.950648] ? kasan_check_read+0x11/0x20 [ 29.954863] ? do_raw_spin_unlock+0x9e/0x310 [ 29.959253] ? do_raw_spin_trylock+0x1a0/0x1a0 [ 29.963813] ? wake_up_q+0xf0/0xf0 [ 29.967342] ? kasan_check_write+0x14/0x20 [ 29.971560] ? do_raw_spin_lock+0xc1/0x230 [ 29.975773] ? __kthread_create_on_node+0x36e/0x480 [ 29.980766] ? print_irqtrace_events+0x270/0x270 [ 29.985494] ? kthread_park+0x130/0x130 [ 29.989448] ? __lock_is_held+0xb6/0x140 [ 29.993492] mutex_lock_nested+0x16/0x20 [ 29.997533] ? mutex_lock_nested+0x16/0x20 [ 30.001744] rtnl_lock+0x17/0x20 [ 30.005086] ip_mc_drop_socket+0x8f/0x240 [ 30.009214] inet_release+0x4e/0x1c0 [ 30.012902] sock_release+0x8d/0x1e0 [ 30.016595] start_sync_thread+0x2213/0x2b70 [ 30.020985] ? ip_vs_process_message_v0+0x870/0x870 [ 30.025981] ? ip_vs_sync_conn+0x3980/0x3980 [ 30.030454] ? find_held_lock+0x35/0x1d0 [ 30.034494] ? trace_hardirqs_off+0x10/0x10 [ 30.038790] ? lock_downgrade+0x980/0x980 [ 30.042922] ? lock_downgrade+0x980/0x980 [ 30.047048] ? lock_release+0xa40/0xa40 [ 30.051006] ? kasan_check_read+0x11/0x20 [ 30.055134] ? do_raw_spin_unlock+0x9e/0x310 [ 30.059526] ? find_held_lock+0x35/0x1d0 [ 30.063567] ? __might_fault+0x110/0x1d0 [ 30.067604] ? __release_sock+0x360/0x360 [ 30.071734] ? lock_release+0xa40/0xa40 [ 30.075681] ? check_same_owner+0x320/0x320 [ 30.079975] ? module_unload_free+0x530/0x530 [ 30.084445] ? __might_sleep+0x95/0x190 [ 30.088426] do_ip_vs_set_ctl+0x1139/0x1cc0 [ 30.092733] ? do_ip_vs_set_ctl+0x1139/0x1cc0 [ 30.097215] ? ip_vs_genl_dump_services+0x440/0x440 [ 30.102216] ? nf_sockopt_find.constprop.0+0x1a7/0x220 [ 30.107471] ? lock_downgrade+0x980/0x980 [ 30.111598] ? _raw_spin_unlock_irq+0x27/0x70 [ 30.116074] ? finish_task_switch+0x1b9/0x970 [ 30.120543] ? finish_task_switch+0x17a/0x970 [ 30.125016] ? copy_overflow+0x20/0x20 [ 30.128890] ? find_held_lock+0x35/0x1d0 [ 30.132930] ? kasan_check_write+0x14/0x20 [ 30.137140] ? __mutex_unlock_slowpath+0x181/0x7e0 [ 30.142049] ? wait_for_completion+0x770/0x770 [ 30.146613] ? kasan_check_read+0x11/0x20 [ 30.150743] ? module_unload_free+0x530/0x530 [ 30.155227] ? rcu_report_exp_cpu_mult+0x480/0x480 [ 30.160138] ? __fget+0x370/0x580 [ 30.163575] compat_nf_setsockopt+0xfa/0x130 [ 30.167956] ? compat_nf_setsockopt+0xfa/0x130 [ 30.172521] compat_ip_setsockopt+0x8b/0xd0 [ 30.176829] compat_udp_setsockopt+0x45/0x80 [ 30.181320] compat_sock_common_setsockopt+0xb2/0x140 [ 30.186491] ? udp_lib_unhash+0x950/0x950 [ 30.190613] ? sock_common_setsockopt+0xd0/0xd0 [ 30.195257] __compat_sys_setsockopt+0x183/0x710 [ 30.199988] ? __compat_sys_getsockopt+0x770/0x770 [ 30.204893] ? trace_hardirqs_off+0xd/0x10 [ 30.209126] ? exit_to_usermode_loop+0x198/0x2f0 [ 30.213857] ? move_addr_to_kernel+0x60/0x60 [ 30.218245] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 30.223768] compat_SyS_setsockopt+0x34/0x50 [ 30.228200] ? scm_detach_fds_compat+0x3d0/0x3d0 [ 30.232950] do_fast_syscall_32+0x3ec/0xf9f [ 30.237265] ? do_int80_syscall_32+0x9c0/0x9c0 [ 30.241936] ? finish_task_switch+0x1b9/0x970 [ 30.246408] ? finish_task_switch+0x17a/0x970 [ 30.250884] ? syscall_return_slowpath+0x2ac/0x550 [ 30.255810] ? prepare_exit_to_usermode+0x350/0x350 [ 30.260818] ? sysret32_from_system_call+0x5/0x3c [ 30.265646] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 30.270472] entry_SYSENTER_compat+0x70/0x7f [ 30.274863] RIP: 0023:0xf7fcdc99 [ 30.278294] RSP: 002b:00000000f7fc90ac EFLAGS: 00000282 ORIG_RAX: 000000000000016e [ 30.285984] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000000000 [ 30.293236] RDX: 000000000000048b RSI: 0000000020000040 RDI: 0000000000000018 [ 30.300499] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 30.307745] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 30.314990] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 30.449765] IPVS: stopping backup sync thread 4660 ... [ 30.450328] IPVS: stopping backup sync thread 4662 ... [ 30.463461] IPVS: stopping backup sync thread 4657 ...