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 '10.128.0.39' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 134.697833] IPVS: ftp: loaded support on port[0] = 21 executing program executing program [ 134.737779] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 134.738150] IPVS: stopping backup sync thread 4533 ... [ 134.757471] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 134.757704] IPVS: stopping backup sync thread 4537 ... [ 134.778401] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 executing program executing program executing program [ 134.778623] IPVS: stopping backup sync thread 4541 ... [ 134.797421] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 134.797649] IPVS: stopping backup sync thread 4545 ... [ 134.817456] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 134.817701] IPVS: stopping backup sync thread 4549 ... executing program executing program [ 134.836744] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 134.837068] IPVS: stopping backup sync thread 4553 ... [ 134.858397] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 134.858750] IPVS: stopping backup sync thread 4557 ... [ 134.879182] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 executing program executing program executing program [ 134.881543] IPVS: stopping backup sync thread 4561 ... [ 134.899892] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 134.903539] IPVS: stopping backup sync thread 4565 ... [ 134.922655] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 134.923176] IPVS: stopping backup sync thread 4569 ... executing program executing program [ 134.942360] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 134.942641] IPVS: stopping backup sync thread 4573 ... [ 134.962306] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 134.962549] IPVS: stopping backup sync thread 4577 ... [ 134.982258] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 executing program executing program executing program [ 134.982499] IPVS: stopping backup sync thread 4581 ... [ 135.001340] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 135.002267] IPVS: stopping backup sync thread 4585 ... [ 135.021056] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 135.021272] IPVS: stopping backup sync thread 4589 ... executing program executing program [ 135.042556] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 135.042813] IPVS: stopping backup sync thread 4593 ... [ 135.063844] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 135.064121] IPVS: stopping backup sync thread 4597 ... [ 135.083184] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 executing program executing program executing program [ 135.083402] IPVS: stopping backup sync thread 4601 ... [ 135.102537] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 135.102825] IPVS: stopping backup sync thread 4605 ... [ 135.122205] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 135.122446] IPVS: stopping backup sync thread 4609 ... executing program executing program [ 135.141891] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 135.142147] IPVS: stopping backup sync thread 4613 ... [ 135.161654] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 135.164468] IPVS: stopping backup sync thread 4617 ... [ 135.182575] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 executing program executing program executing program [ 135.182829] IPVS: stopping backup sync thread 4621 ... [ 135.203513] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 135.203747] IPVS: stopping backup sync thread 4625 ... [ 135.223130] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 135.223365] IPVS: stopping backup sync thread 4629 ... [ 135.242365] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 135.243268] IPVS: stopping backup sync thread 4633 ... [ 135.256355] [ 135.257961] ============================================ [ 135.263379] WARNING: possible recursive locking detected [ 135.268798] 4.16.0+ #3 Not tainted [ 135.272465] -------------------------------------------- [ 135.277888] syzkaller741987/4632 is trying to acquire lock: [ 135.283569] 00000000c90b6d40 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 135.290408] [ 135.290408] but task is already holding lock: [ 135.296350] 00000000c90b6d40 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 135.303170] [ 135.303170] other info that might help us debug this: [ 135.309806] Possible unsafe locking scenario: [ 135.309806] [ 135.315832] CPU0 [ 135.318385] ---- [ 135.320938] lock(rtnl_mutex); [ 135.324190] lock(rtnl_mutex); [ 135.327440] [ 135.327440] *** DEADLOCK *** [ 135.327440] [ 135.333478] May be due to missing lock nesting notation [ 135.333478] [ 135.340375] 2 locks held by syzkaller741987/4632: [ 135.345186] #0: 00000000c90b6d40 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 135.352440] #1: 000000000e01c1fa (ipvs->sync_mutex){+.+.}, at: do_ip_vs_set_ctl+0x562/0x1d30 [ 135.361085] [ 135.361085] stack backtrace: [ 135.365558] CPU: 1 PID: 4632 Comm: syzkaller741987 Not tainted 4.16.0+ #3 [ 135.372453] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 135.381779] Call Trace: [ 135.384341] dump_stack+0x1b9/0x294 [ 135.387942] ? dump_stack_print_info.cold.2+0x52/0x52 [ 135.393107] ? print_lock+0xd1/0xd6 [ 135.396710] ? vprintk_func+0x81/0xe7 [ 135.400486] __lock_acquire.cold.62+0x18c/0x55b [ 135.405131] ? debug_check_no_locks_freed+0x310/0x310 [ 135.410296] ? __enqueue_entity+0x10d/0x1f0 [ 135.414590] ? __lock_is_held+0xb5/0x140 [ 135.418627] ? __lock_acquire+0x7f5/0x5140 [ 135.422845] ? select_idle_sibling+0xd70/0xd70 [ 135.427401] ? lock_downgrade+0x8e0/0x8e0 [ 135.431537] ? graph_lock+0x170/0x170 [ 135.435313] ? kasan_check_read+0x11/0x20 [ 135.439441] ? graph_lock+0x170/0x170 [ 135.443221] ? graph_lock+0x170/0x170 [ 135.447000] lock_acquire+0x1dc/0x520 [ 135.450775] ? rtnl_lock+0x17/0x20 [ 135.454289] ? lock_release+0xa10/0xa10 [ 135.458238] ? check_same_owner+0x320/0x320 [ 135.462533] ? graph_lock+0x170/0x170 [ 135.466308] ? rcu_note_context_switch+0x710/0x710 [ 135.471211] ? __might_sleep+0x95/0x190 [ 135.475161] ? rtnl_lock+0x17/0x20 [ 135.478675] __mutex_lock+0x16d/0x17f0 [ 135.482535] ? rtnl_lock+0x17/0x20 [ 135.486049] ? rtnl_lock+0x17/0x20 [ 135.489564] ? mutex_trylock+0x2a0/0x2a0 [ 135.493599] ? mark_held_locks+0xc9/0x160 [ 135.497723] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 135.502280] ? _raw_spin_unlock_irq+0x27/0x70 [ 135.506751] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 135.511741] ? trace_hardirqs_on+0xd/0x10 [ 135.515862] ? _raw_spin_unlock_irq+0x27/0x70 [ 135.520333] ? wait_for_completion_killable+0x56c/0x960 [ 135.525674] ? wait_for_completion_interruptible_timeout+0x960/0x960 [ 135.532139] ? lock_downgrade+0x8e0/0x8e0 [ 135.536261] ? kasan_check_read+0x11/0x20 [ 135.540382] ? do_raw_spin_unlock+0x9e/0x2e0 [ 135.544766] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 135.549324] ? wake_up_q+0x100/0x100 [ 135.553014] ? kasan_check_write+0x14/0x20 [ 135.557225] ? do_raw_spin_lock+0xc1/0x200 [ 135.561437] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 135.566950] ? __kthread_create_on_node+0x34f/0x4c0 [ 135.571940] ? __kthread_parkme+0x280/0x280 [ 135.576233] ? kasan_check_read+0x11/0x20 [ 135.580354] ? do_raw_spin_unlock+0x9e/0x2e0 [ 135.584735] ? __lock_is_held+0xb5/0x140 [ 135.588768] mutex_lock_nested+0x16/0x20 [ 135.592801] ? mutex_lock_nested+0x16/0x20 [ 135.597016] rtnl_lock+0x17/0x20 [ 135.600361] ip_mc_drop_socket+0x8f/0x270 [ 135.604486] inet_release+0x4e/0x1f0 [ 135.608174] sock_release+0x96/0x1b0 [ 135.611862] start_sync_thread+0xdc3/0x2d40 [ 135.616158] ? ip_vs_process_message+0xa0a/0xa0a [ 135.620905] ? ip_vs_sync_conn+0x33a0/0x33a0 [ 135.625288] ? graph_lock+0x170/0x170 [ 135.629063] ? lock_downgrade+0x8e0/0x8e0 [ 135.633183] ? lock_downgrade+0x8e0/0x8e0 [ 135.637305] ? kasan_check_read+0x11/0x20 [ 135.641434] ? do_raw_spin_unlock+0x9e/0x2e0 [ 135.645818] ? __local_bh_enable_ip+0x161/0x230 [ 135.650476] ? find_held_lock+0x36/0x1c0 [ 135.654511] ? lock_downgrade+0x8e0/0x8e0 [ 135.658636] ? lock_release+0xa10/0xa10 [ 135.662589] ? check_same_owner+0x320/0x320 [ 135.666888] ? module_unload_free+0x5b0/0x5b0 [ 135.671357] ? __might_sleep+0x95/0x190 [ 135.675306] do_ip_vs_set_ctl+0x59c/0x1d30 [ 135.679514] ? find_held_lock+0x36/0x1c0 [ 135.683550] ? ip_vs_genl_set_cmd+0xe80/0xe80 [ 135.688018] ? lock_downgrade+0x8e0/0x8e0 [ 135.692139] ? kasan_check_read+0x11/0x20 [ 135.696261] ? rcu_is_watching+0x85/0x140 [ 135.700385] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 135.705549] ? kasan_check_write+0x14/0x20 [ 135.709758] ? __mutex_unlock_slowpath+0x180/0x8a0 [ 135.714663] ? wait_for_completion+0x870/0x870 [ 135.719220] ? module_unload_free+0x5b0/0x5b0 [ 135.723692] ? retint_kernel+0x10/0x10 [ 135.727557] ? nf_sockopt_find.constprop.0+0xa3/0x290 [ 135.732722] ? mutex_unlock+0xd/0x10 [ 135.736409] nf_setsockopt+0x7d/0xd0 [ 135.740096] ? nf_setsockopt+0x7d/0xd0 [ 135.743959] ip_setsockopt+0xd8/0xf0 [ 135.747650] tcp_setsockopt+0x93/0xe0 [ 135.751433] sock_common_setsockopt+0x9a/0xe0 [ 135.755905] __sys_setsockopt+0x1bd/0x390 [ 135.760027] ? kernel_accept+0x310/0x310 [ 135.764061] ? do_futex+0x27d0/0x27d0 [ 135.767836] ? mm_fault_error+0x380/0x380 [ 135.771957] ? do_raw_spin_unlock+0x9e/0x2e0 [ 135.776339] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 135.780894] SyS_setsockopt+0x34/0x50 [ 135.784669] ? SyS_recv+0x40/0x40 [ 135.788098] do_syscall_64+0x29e/0x9d0 [ 135.791958] ? vmalloc_sync_all+0x30/0x30 [ 135.796079] ? kasan_check_write+0x14/0x20 [ 135.800287] ? syscall_return_slowpath+0x5c0/0x5c0 [ 135.805192] ? syscall_return_slowpath+0x30f/0x5c0 [ 135.810096] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 135.815435] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 135.820251] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 135.825423] RIP: 0033:0x4479e9 [ 135.828590] RSP: 002b:00007f724d1aadb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 [ 135.836274] RAX: ffffffffffffffda RBX: 00000000006e39e4 RCX: 00000000004479e9 [ 135.843522] RDX: 000000000000048b RSI: 0000000000000000 RDI: 0000000000000004 [ 135.850766] RBP: 00000000006e39e0 R08: 0000000000000018 R09: 0000000000000000 [ 135.858008] R10: 0000000020000080 R11: 0000000000000246 R12: 0000000000000000 [ 135.865253] R13: 00007ffe5bd3a9bf R14: 00007f724d1ab9c0 R15: 0000000000000004