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 '10.128.10.7' (ECDSA) to the list of known hosts. syzkaller login: [ 29.071858] IPVS: ftp: loaded support on port[0] = 21 [ 29.080362] IPVS: ftp: loaded support on port[0] = 21 [ 29.084754] IPVS: ftp: loaded support on port[0] = 21 [ 29.087708] IPVS: ftp: loaded support on port[0] = 21 [ 29.092944] IPVS: ftp: loaded support on port[0] = 21 [ 29.097561] IPVS: ftp: loaded support on port[0] = 21 [ 29.101628] IPVS: ftp: loaded support on port[0] = 21 [ 29.107869] IPVS: ftp: loaded support on port[0] = 21 executing program executing program executing program executing program [ 29.259122] IPVS: stopping backup sync thread 4520 ... executing program [ 29.283189] IPVS: stopping backup sync thread 4525 ... executing program executing program executing program executing program [ 29.305468] IPVS: stopping backup sync thread 4529 ... [ 29.306130] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 29.322708] IPVS: stopping backup sync thread 4533 ... [ 29.329646] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 29.330004] IPVS: stopping backup sync thread 4537 ... [ 29.344415] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 executing program executing program executing program executing program [ 29.344973] IPVS: stopping backup sync thread 4541 ... [ 29.360009] IPVS: stopping backup sync thread 4543 ... [ 29.360913] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 29.366754] IPVS: stopping backup sync thread 4547 ... [ 29.374231] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 29.383578] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 29.398724] IPVS: stopping backup sync thread 4549 ... executing program [ 29.402298] IPVS: stopping backup sync thread 4554 ... [ 29.404384] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 29.410493] [ 29.419417] ============================================ [ 29.424849] WARNING: possible recursive locking detected [ 29.430285] 4.16.0+ #2 Not tainted [ 29.433804] -------------------------------------------- [ 29.439231] syzkaller201633/4542 is trying to acquire lock: [ 29.444931] 000000003c586f0f (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 29.451790] [ 29.451790] but task is already holding lock: [ 29.457747] 000000003c586f0f (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 29.464587] [ 29.464587] other info that might help us debug this: [ 29.471229] Possible unsafe locking scenario: [ 29.471229] [ 29.477259] CPU0 [ 29.479814] ---- [ 29.482369] lock(rtnl_mutex); [ 29.485623] lock(rtnl_mutex); [ 29.488877] [ 29.488877] *** DEADLOCK *** [ 29.488877] [ 29.494919] May be due to missing lock nesting notation [ 29.494919] [ 29.501937] 2 locks held by syzkaller201633/4542: [ 29.506752] #0: 000000003c586f0f (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 29.514032] #1: 000000006975204a (ipvs->sync_mutex){+.+.}, at: do_ip_vs_set_ctl+0x562/0x1d30 [ 29.522702] [ 29.522702] stack backtrace: [ 29.527181] CPU: 1 PID: 4542 Comm: syzkaller201633 Not tainted 4.16.0+ #2 [ 29.534078] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 29.543403] Call Trace: [ 29.545979] dump_stack+0x1b9/0x294 [ 29.549582] ? dump_stack_print_info.cold.2+0x52/0x52 [ 29.554752] ? print_lock+0xd1/0xd6 [ 29.558354] ? vprintk_func+0x81/0xe7 [ 29.562133] __lock_acquire.cold.62+0x18c/0x55b [ 29.566787] ? debug_check_no_locks_freed+0x310/0x310 [ 29.571956] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.576438] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 29.581436] ? trace_hardirqs_on+0xd/0x10 [ 29.585560] ? __lock_acquire+0x7f5/0x5140 [ 29.589778] ? copy_overflow+0x20/0x20 [ 29.593645] ? debug_check_no_locks_freed+0x310/0x310 [ 29.598814] ? __schedule+0x809/0x1e30 [ 29.602678] ? graph_lock+0x170/0x170 [ 29.606457] ? kasan_check_read+0x11/0x20 [ 29.610582] ? graph_lock+0x170/0x170 [ 29.614356] ? graph_lock+0x170/0x170 [ 29.618135] lock_acquire+0x1dc/0x520 [ 29.621923] ? rtnl_lock+0x17/0x20 [ 29.625441] ? lock_release+0xa10/0xa10 [ 29.629395] ? check_same_owner+0x320/0x320 [ 29.633703] ? schedule+0xef/0x430 [ 29.637232] ? rcu_note_context_switch+0x710/0x710 [ 29.642150] ? __schedule+0x1e30/0x1e30 [ 29.646105] ? __might_sleep+0x95/0x190 [ 29.650069] ? rtnl_lock+0x17/0x20 [ 29.653591] __mutex_lock+0x16d/0x17f0 [ 29.657552] ? rtnl_lock+0x17/0x20 [ 29.661066] ? rtnl_lock+0x17/0x20 [ 29.664595] ? mutex_trylock+0x2a0/0x2a0 [ 29.668634] ? mark_held_locks+0xc9/0x160 [ 29.672760] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 29.677318] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.681788] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 29.686778] ? trace_hardirqs_on+0xd/0x10 [ 29.690904] ? _raw_spin_unlock_irq+0x27/0x70 [ 29.695386] ? wait_for_completion_killable+0x56c/0x960 [ 29.700910] ? wait_for_completion_interruptible_timeout+0x960/0x960 [ 29.707468] ? lock_downgrade+0x8e0/0x8e0 [ 29.711598] ? kasan_check_read+0x11/0x20 [ 29.715737] ? do_raw_spin_unlock+0x9e/0x2e0 [ 29.720136] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 29.724702] ? wake_up_q+0x100/0x100 [ 29.728395] ? kasan_check_write+0x14/0x20 [ 29.732610] ? do_raw_spin_lock+0xc1/0x200 [ 29.736837] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 29.742359] ? __kthread_create_on_node+0x34f/0x4c0 [ 29.747367] ? __kthread_parkme+0x280/0x280 [ 29.751675] ? kasan_check_read+0x11/0x20 [ 29.755805] ? do_raw_spin_unlock+0x9e/0x2e0 [ 29.760209] ? __lock_is_held+0xb5/0x140 [ 29.764256] mutex_lock_nested+0x16/0x20 [ 29.768297] ? mutex_lock_nested+0x16/0x20 [ 29.772520] rtnl_lock+0x17/0x20 [ 29.775869] ip_mc_drop_socket+0x8f/0x270 [ 29.780000] inet_release+0x4e/0x1f0 [ 29.783702] sock_release+0x96/0x1b0 [ 29.787396] start_sync_thread+0xdc3/0x2d40 [ 29.791698] ? __lock_acquire+0x7f5/0x5140 [ 29.795912] ? ip_vs_process_message+0xa0a/0xa0a [ 29.800647] ? ip_vs_sync_conn+0x33a0/0x33a0 [ 29.805042] ? graph_lock+0x170/0x170 [ 29.808824] ? lock_downgrade+0x8e0/0x8e0 [ 29.812952] ? lock_downgrade+0x8e0/0x8e0 [ 29.817080] ? kasan_check_read+0x11/0x20 [ 29.821222] ? do_raw_spin_unlock+0x9e/0x2e0 [ 29.825785] ? __local_bh_enable_ip+0x161/0x230 [ 29.830448] ? find_held_lock+0x36/0x1c0 [ 29.834489] ? lock_downgrade+0x8e0/0x8e0 [ 29.838617] ? lock_release+0xa10/0xa10 [ 29.842584] ? check_same_owner+0x320/0x320 [ 29.846888] ? module_unload_free+0x5b0/0x5b0 [ 29.851375] do_ip_vs_set_ctl+0x59c/0x1d30 [ 29.855593] ? find_held_lock+0x36/0x1c0 [ 29.859639] ? ip_vs_genl_set_cmd+0xe80/0xe80 [ 29.864132] ? lock_downgrade+0x8e0/0x8e0 [ 29.868265] ? kasan_check_read+0x11/0x20 [ 29.872397] ? rcu_is_watching+0x85/0x140 [ 29.876530] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 29.881704] ? kasan_check_write+0x14/0x20 [ 29.885927] ? __mutex_unlock_slowpath+0x180/0x8a0 [ 29.890855] ? wait_for_completion+0x870/0x870 [ 29.895435] ? module_unload_free+0x5b0/0x5b0 [ 29.899923] ? __fget+0x40c/0x650 [ 29.903373] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 29.908916] ? mutex_unlock+0xd/0x10 [ 29.912632] nf_setsockopt+0x7d/0xd0 [ 29.916338] ? nf_setsockopt+0x7d/0xd0 [ 29.920217] ip_setsockopt+0xd8/0xf0 [ 29.923927] tcp_setsockopt+0x93/0xe0 [ 29.927723] sock_common_setsockopt+0x9a/0xe0 [ 29.932204] __sys_setsockopt+0x1bd/0x390 [ 29.936340] ? kernel_accept+0x310/0x310 [ 29.940403] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 29.945941] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 29.950786] SyS_setsockopt+0x34/0x50 [ 29.954574] ? SyS_recv+0x40/0x40 [ 29.958031] do_syscall_64+0x29e/0x9d0 [ 29.961909] ? vmalloc_sync_all+0x30/0x30 [ 29.966060] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 29.970892] ? syscall_return_slowpath+0x5c0/0x5c0 [ 29.975809] ? syscall_return_slowpath+0x30f/0x5c0 [ 29.980728] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 29.986130] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 29.990965] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 29.996147] RIP: 0033:0x446ab9 [ 29.999325] RSP: 002b:00007f105c6d4da8 EFLAGS: 00000293 ORIG_RAX: 0000000000000036 [ 30.007022] RAX: ffffffffffffffda RBX: 00000000006e29e4 RCX: 0000000000446ab9 [ 30.014283] RDX: 000000000000048b RSI: 0000000000000000 RDI: 0000000000000003 [ 30.021547] RBP: 0000000000000000 R08: 0000000000000018 R09: 0000000000000000 [ 30.028887] R10: 0000000020000080 R11: 0000000000000293 R12: 00000000006e29e0 [ 30.036142] R13: 7475612f7665642f R14: 00007f105c6d59c0 R15: 00000000006e2b60