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 '10.128.0.58' (ECDSA) to the list of known hosts. syzkaller login: [ 28.602243] IPVS: ftp: loaded support on port[0] = 21 [ 28.610298] IPVS: ftp: loaded support on port[0] = 21 [ 28.619791] IPVS: ftp: loaded support on port[0] = 21 [ 28.619797] IPVS: ftp: loaded support on port[0] = 21 [ 28.626258] IPVS: ftp: loaded support on port[0] = 21 [ 28.631547] IPVS: ftp: loaded support on port[0] = 21 [ 28.635774] IPVS: ftp: loaded support on port[0] = 21 [ 28.643130] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program executing program executing program [ 28.783462] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.788176] IPVS: stopping backup sync thread 4510 ... [ 28.791903] IPVS: stopping backup sync thread 4509 ... executing program executing program executing program [ 28.831390] IPVS: stopping backup sync thread 4520 ... [ 28.837493] IPVS: stopping backup sync thread 4522 ... [ 28.848620] IPVS: stopping backup sync thread 4523 ... [ 28.850055] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.858557] IPVS: stopping backup sync thread 4528 ... [ 28.868403] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 executing program executing program executing program executing program executing program executing program [ 28.876945] IPVS: stopping backup sync thread 4529 ... [ 28.883350] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.883354] IPVS: stopping backup sync thread 4534 ... [ 28.897553] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.902496] IPVS: stopping backup sync thread 4544 ... [ 28.912097] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.913245] IPVS: stopping backup sync thread 4546 ... [ 28.924170] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.926742] IPVS: stopping backup sync thread 4549 ... [ 28.936815] IPVS: stopping backup sync thread 4552 ... [ 28.939931] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.947179] [ 28.955041] ============================================ [ 28.960465] WARNING: possible recursive locking detected [ 28.965892] 4.17.0-rc1+ #9 Not tainted [ 28.969752] -------------------------------------------- [ 28.975178] syzkaller240157/4543 is trying to acquire lock: [ 28.980863] 000000005b7d2f39 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 28.987697] [ 28.987697] but task is already holding lock: [ 28.993644] 000000005b7d2f39 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 29.000470] [ 29.000470] other info that might help us debug this: [ 29.007115] Possible unsafe locking scenario: [ 29.007115] [ 29.013148] CPU0 [ 29.015707] ---- [ 29.018265] lock(rtnl_mutex); [ 29.021522] lock(rtnl_mutex); [ 29.024779] [ 29.024779] *** DEADLOCK *** [ 29.024779] [ 29.030816] May be due to missing lock nesting notation [ 29.030816] [ 29.037726] 2 locks held by syzkaller240157/4543: [ 29.042543] #0: 000000005b7d2f39 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 29.049813] #1: 0000000010e17c8d (ipvs->sync_mutex){+.+.}, at: do_ip_vs_set_ctl+0x562/0x1d30 [ 29.058472] [ 29.058472] stack backtrace: [ 29.062959] CPU: 1 PID: 4543 Comm: syzkaller240157 Not tainted 4.17.0-rc1+ #9 [ 29.070209] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.079545] Call Trace: [ 29.082121] dump_stack+0x1b9/0x294 [ 29.085732] ? dump_stack_print_info.cold.2+0x52/0x52 [ 29.090902] ? print_lock+0xd1/0xd6 [ 29.094512] ? vprintk_func+0x81/0xe7 [ 29.098299] __lock_acquire.cold.62+0x18c/0x55b [ 29.102955] ? debug_check_no_locks_freed+0x310/0x310 [ 29.108127] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.112606] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 29.117604] ? trace_hardirqs_on+0xd/0x10 [ 29.121734] ? __lock_acquire+0x7f5/0x5140 [ 29.125953] ? preempt_notifier_register+0x1e0/0x1e0 [ 29.131041] ? debug_check_no_locks_freed+0x310/0x310 [ 29.136212] ? __schedule+0x809/0x1e30 [ 29.140082] ? graph_lock+0x170/0x170 [ 29.143863] ? graph_lock+0x170/0x170 [ 29.147647] ? rcu_is_watching+0x85/0x140 [ 29.151774] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 29.156944] ? graph_lock+0x170/0x170 [ 29.160726] ? graph_lock+0x170/0x170 [ 29.164512] lock_acquire+0x1dc/0x520 [ 29.168297] ? rtnl_lock+0x17/0x20 [ 29.171819] ? lock_release+0xa10/0xa10 [ 29.175773] ? check_same_owner+0x320/0x320 [ 29.180085] ? schedule+0xef/0x430 [ 29.183609] ? rcu_note_context_switch+0x710/0x710 [ 29.188520] ? __schedule+0x1e30/0x1e30 [ 29.192479] ? __might_sleep+0x95/0x190 [ 29.196439] ? rtnl_lock+0x17/0x20 [ 29.199961] __mutex_lock+0x16d/0x17f0 [ 29.203835] ? rtnl_lock+0x17/0x20 [ 29.207365] ? rtnl_lock+0x17/0x20 [ 29.211064] ? mutex_trylock+0x2a0/0x2a0 [ 29.215107] ? mark_held_locks+0xc9/0x160 [ 29.219235] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 29.223804] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.228281] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 29.233279] ? trace_hardirqs_on+0xd/0x10 [ 29.237412] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.241891] ? wait_for_completion_killable+0x56c/0x960 [ 29.247240] ? wait_for_completion_interruptible_timeout+0x960/0x960 [ 29.253716] ? lock_downgrade+0x8e0/0x8e0 [ 29.257848] ? kasan_check_read+0x11/0x20 [ 29.261978] ? do_raw_spin_unlock+0x9e/0x2e0 [ 29.266377] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 29.270948] ? wake_up_q+0x100/0x100 [ 29.274644] ? kasan_check_write+0x14/0x20 [ 29.278857] ? do_raw_spin_lock+0xc1/0x200 [ 29.283076] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 29.288610] ? __kthread_create_on_node+0x34f/0x4c0 [ 29.293619] ? __kthread_parkme+0x280/0x280 [ 29.297925] ? kasan_check_read+0x11/0x20 [ 29.302057] ? do_raw_spin_unlock+0x9e/0x2e0 [ 29.306452] ? __lock_is_held+0xb5/0x140 [ 29.310498] mutex_lock_nested+0x16/0x20 [ 29.314544] ? mutex_lock_nested+0x16/0x20 [ 29.318756] rtnl_lock+0x17/0x20 [ 29.322103] ip_mc_drop_socket+0x8f/0x270 [ 29.326236] inet_release+0x4e/0x1f0 [ 29.329931] sock_release+0x96/0x1b0 [ 29.333625] start_sync_thread+0xdc3/0x2d40 [ 29.337928] ? ip_vs_process_message+0xa0a/0xa0a [ 29.342664] ? ip_vs_sync_conn+0x33a0/0x33a0 [ 29.347055] ? graph_lock+0x170/0x170 [ 29.350837] ? lock_downgrade+0x8e0/0x8e0 [ 29.354966] ? lock_downgrade+0x8e0/0x8e0 [ 29.359100] ? kasan_check_read+0x11/0x20 [ 29.363233] ? do_raw_spin_unlock+0x9e/0x2e0 [ 29.367628] ? __local_bh_enable_ip+0x161/0x230 [ 29.372276] ? find_held_lock+0x36/0x1c0 [ 29.376317] ? lock_downgrade+0x8e0/0x8e0 [ 29.380447] ? lock_release+0xa10/0xa10 [ 29.384407] ? check_same_owner+0x320/0x320 [ 29.388708] ? module_unload_free+0x5b0/0x5b0 [ 29.393194] do_ip_vs_set_ctl+0x59c/0x1d30 [ 29.397411] ? find_held_lock+0x36/0x1c0 [ 29.401455] ? ip_vs_genl_set_cmd+0xe80/0xe80 [ 29.405932] ? lock_downgrade+0x8e0/0x8e0 [ 29.410064] ? kasan_check_read+0x11/0x20 [ 29.414195] ? rcu_is_watching+0x85/0x140 [ 29.418324] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 29.423501] ? kasan_check_write+0x14/0x20 [ 29.427719] ? __mutex_unlock_slowpath+0x180/0x8a0 [ 29.432632] ? wait_for_completion+0x870/0x870 [ 29.437196] ? module_unload_free+0x5b0/0x5b0 [ 29.441678] ? mutex_unlock+0xd/0x10 [ 29.445375] nf_setsockopt+0x7d/0xd0 [ 29.449077] ? nf_setsockopt+0x7d/0xd0 [ 29.452962] ip_setsockopt+0xd8/0xf0 [ 29.456660] tcp_setsockopt+0x93/0xe0 [ 29.460444] sock_common_setsockopt+0x9a/0xe0 [ 29.464920] __sys_setsockopt+0x1bd/0x390 [ 29.469051] ? kernel_accept+0x310/0x310 [ 29.473113] ? mm_fault_error+0x380/0x380 [ 29.477244] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 29.482763] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 29.487588] __x64_sys_setsockopt+0xbe/0x150 [ 29.491984] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 29.496996] do_syscall_64+0x1b1/0x800 [ 29.500872] ? finish_task_switch+0x1ca/0x810 [ 29.505350] ? syscall_return_slowpath+0x5c0/0x5c0 [ 29.510263] ? syscall_return_slowpath+0x30f/0x5c0 [ 29.515176] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 29.520692] ? retint_user+0x18/0x18 [ 29.524390] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.529214] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 29.534386] RIP: 0033:0x446ce9 [ 29.537553] RSP: 002b:00007fb226a60ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 [ 29.545242] RAX: ffffffffffffffda RBX: 00000000006e29e4 RCX: 0000000000446ce9 [ 29.552495] RDX: 000000000000048b RSI: 0000000000000000 RDI: 0000000000000003 [ 29.559747] RBP: 00000000006e29e0 R08: 0000000000000018 R09: 0000000000000000 [ 29.567004] R10: 0000000020000040 R11: 0000000000000246 R12: 0000000000000000 [ 29.574261] R13: 00007ffefa1166cf R14: 00007fb226a619c0 R15: 00000000006e2b60