Warning: Permanently added '10.128.10.19' (ECDSA) to the list of known hosts. [ 31.612830] IPVS: ftp: loaded support on port[0] = 21 [ 31.618448] IPVS: ftp: loaded support on port[0] = 21 [ 31.627497] IPVS: ftp: loaded support on port[0] = 21 [ 31.629749] IPVS: ftp: loaded support on port[0] = 21 [ 31.640354] IPVS: ftp: loaded support on port[0] = 21 [ 31.640500] IPVS: ftp: loaded support on port[0] = 21 [ 31.647713] IPVS: ftp: loaded support on port[0] = 21 [ 31.652945] IPVS: ftp: loaded support on port[0] = 21 [ 31.817584] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 31.852489] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 31.861633] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 31.862183] IPVS: stopping backup sync thread 4546 ... [ 31.873369] [ 31.877008] ============================================ [ 31.879004] IPVS: stopping backup sync thread 4559 ... [ 31.882443] WARNING: possible recursive locking detected [ 31.882451] 4.16.0+ #19 Not tainted [ 31.882454] -------------------------------------------- [ 31.882460] syzkaller046099/4543 is trying to acquire lock: [ 31.882465] 000000008d06d497 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 31.882498] [ 31.882498] but task is already holding lock: [ 31.888789] IPVS: stopping backup sync thread 4557 ... [ 31.893193] 000000008d06d497 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 31.893222] [ 31.893222] other info that might help us debug this: [ 31.893225] Possible unsafe locking scenario: [ 31.893225] [ 31.893226] CPU0 [ 31.893228] ---- [ 31.893230] lock(rtnl_mutex); [ 31.893237] lock(rtnl_mutex); [ 31.893243] [ 31.893243] *** DEADLOCK *** [ 31.893243] [ 31.893246] May be due to missing lock nesting notation [ 31.893246] [ 31.893253] 2 locks held by syzkaller046099/4543: [ 31.893255] #0: 000000008d06d497 (rtnl_mutex){+.+.}, at: rtnl_lock+0x17/0x20 [ 31.982187] #1: 000000008326bc5c (ipvs->sync_mutex){+.+.}, at: do_ip_vs_set_ctl+0x562/0x1d30 [ 31.990867] [ 31.990867] stack backtrace: [ 31.995365] CPU: 1 PID: 4543 Comm: syzkaller046099 Not tainted 4.16.0+ #19 [ 32.002358] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 32.011694] Call Trace: [ 32.014277] dump_stack+0x1b9/0x294 [ 32.017905] ? dump_stack_print_info.cold.2+0x52/0x52 [ 32.023085] ? print_lock+0xd1/0xd6 [ 32.026703] ? vprintk_func+0x81/0xe7 [ 32.030499] __lock_acquire.cold.62+0x18c/0x55b [ 32.035152] ? debug_check_no_locks_freed+0x310/0x310 [ 32.040332] ? account_kernel_stack+0x2bd/0x410 [ 32.044991] ? trace_hardirqs_on+0xd/0x10 [ 32.049127] ? put_task_stack+0x188/0x2c0 [ 32.053271] ? __lock_acquire+0x7f5/0x5130 [ 32.057509] ? copy_overflow+0x20/0x20 [ 32.061385] ? debug_check_no_locks_freed+0x310/0x310 [ 32.066575] ? __schedule+0x80f/0x1e40 [ 32.070451] ? graph_lock+0x170/0x170 [ 32.074247] ? kasan_check_read+0x11/0x20 [ 32.078379] ? graph_lock+0x170/0x170 [ 32.082162] ? graph_lock+0x170/0x170 [ 32.085974] lock_acquire+0x1dc/0x520 [ 32.089765] ? rtnl_lock+0x17/0x20 [ 32.093296] ? lock_release+0xa10/0xa10 [ 32.097260] ? check_same_owner+0x320/0x320 [ 32.101582] ? schedule+0xef/0x430 [ 32.105111] ? rcu_note_context_switch+0x710/0x710 [ 32.110033] ? __schedule+0x1e40/0x1e40 [ 32.114001] ? __might_sleep+0x95/0x190 [ 32.118323] ? rtnl_lock+0x17/0x20 [ 32.121858] __mutex_lock+0x16d/0x17f0 [ 32.125755] ? rtnl_lock+0x17/0x20 [ 32.129279] ? rtnl_lock+0x17/0x20 [ 32.132810] ? mutex_trylock+0x2a0/0x2a0 [ 32.136861] ? mark_held_locks+0xc9/0x160 [ 32.141340] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.145917] ? _raw_spin_unlock_irq+0x27/0x70 [ 32.150498] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.155511] ? trace_hardirqs_on+0xd/0x10 [ 32.159659] ? _raw_spin_unlock_irq+0x27/0x70 [ 32.164148] ? wait_for_completion_killable+0x56c/0x960 [ 32.169499] ? wait_for_completion_interruptible_timeout+0x960/0x960 [ 32.175993] ? lock_downgrade+0x8e0/0x8e0 [ 32.180131] ? kasan_check_read+0x11/0x20 [ 32.184262] ? do_raw_spin_unlock+0x9e/0x2e0 [ 32.188674] ? do_raw_spin_trylock+0x1b0/0x1b0 [ 32.193260] ? wake_up_q+0x100/0x100 [ 32.196969] ? kasan_check_write+0x14/0x20 [ 32.201204] ? do_raw_spin_lock+0xc1/0x200 [ 32.205424] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.210948] ? __kthread_create_on_node+0x34f/0x4c0 [ 32.215957] ? __kthread_parkme+0x280/0x280 [ 32.220260] ? kasan_check_read+0x11/0x20 [ 32.224385] ? do_raw_spin_unlock+0x9e/0x2e0 [ 32.228778] ? __lock_is_held+0xb5/0x140 [ 32.232834] mutex_lock_nested+0x16/0x20 [ 32.236888] ? mutex_lock_nested+0x16/0x20 [ 32.241124] rtnl_lock+0x17/0x20 [ 32.244486] ip_mc_drop_socket+0x8f/0x270 [ 32.248797] inet_release+0x4e/0x1f0 [ 32.252503] sock_release+0x96/0x1b0 [ 32.256204] start_sync_thread+0xdc3/0x2d40 [ 32.260511] ? ip_vs_process_message+0xa0a/0xa0a [ 32.265334] ? ip_vs_sync_conn+0x33a0/0x33a0 [ 32.269725] ? graph_lock+0x170/0x170 [ 32.273524] ? lock_downgrade+0x8e0/0x8e0 [ 32.277670] ? kasan_check_read+0x11/0x20 [ 32.281807] ? do_raw_spin_unlock+0x9e/0x2e0 [ 32.286210] ? find_held_lock+0x36/0x1c0 [ 32.290255] ? lock_downgrade+0x8e0/0x8e0 [ 32.294407] ? __release_sock+0x3a0/0x3a0 [ 32.298642] ? lock_release+0xa10/0xa10 [ 32.302632] ? check_same_owner+0x320/0x320 [ 32.306958] ? module_unload_free+0x5b0/0x5b0 [ 32.311447] do_ip_vs_set_ctl+0x59c/0x1d30 [ 32.315681] ? ip_vs_genl_set_cmd+0xe80/0xe80 [ 32.320171] ? lock_downgrade+0x8e0/0x8e0 [ 32.324301] ? lock_downgrade+0x8e0/0x8e0 [ 32.328433] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 32.333438] ? kasan_check_read+0x11/0x20 [ 32.337570] ? rcu_is_watching+0x85/0x140 [ 32.341707] ? rcu_bh_force_quiescent_state+0x20/0x20 [ 32.346880] ? kasan_check_write+0x14/0x20 [ 32.351111] ? __mutex_unlock_slowpath+0x180/0x8a0 [ 32.356046] ? wait_for_completion+0x870/0x870 [ 32.360634] ? module_unload_free+0x5b0/0x5b0 [ 32.365119] ? expand_files.part.8+0x9a0/0x9a0 [ 32.369690] nf_setsockopt+0x7d/0xd0 [ 32.373490] ? ip_vs_genl_set_cmd+0xe80/0xe80 [ 32.377969] ? nf_setsockopt+0x7d/0xd0 [ 32.381846] ip_setsockopt+0xd8/0xf0 [ 32.385542] udp_setsockopt+0x62/0xa0 [ 32.389337] ipv6_setsockopt+0x149/0x170 [ 32.393402] udpv6_setsockopt+0x62/0xa0 [ 32.397542] sock_common_setsockopt+0x9a/0xe0 [ 32.402038] __sys_setsockopt+0x1bd/0x390 [ 32.406190] ? kernel_accept+0x310/0x310 [ 32.410251] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 32.415783] ? syscall_slow_exit_work+0x4f0/0x4f0 [ 32.420624] SyS_setsockopt+0x34/0x50 [ 32.424417] ? SyS_recv+0x40/0x40 [ 32.427855] do_syscall_64+0x29e/0x9d0 [ 32.431727] ? vmalloc_sync_all+0x30/0x30 [ 32.435858] ? _raw_spin_unlock_irq+0x27/0x70 [ 32.440337] ? finish_task_switch+0x1ca/0x820 [ 32.444816] ? syscall_return_slowpath+0x5c0/0x5c0 [ 32.449729] ? syscall_return_slowpath+0x30f/0x5c0 [ 32.454654] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 32.460028] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 32.464860] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 32.470038] RIP: 0033:0x447c19 [ 32.473220] RSP: 002b:00007fb627a93db8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 [ 32.480908] RAX: ffffffffffffffda RBX: 0000000000700024 RCX: 0000000000447c19 [ 32.488161] RDX: 000000000000048b RSI: 0000000000000000 RDI: 0000000000000004 [ 32.495415] RBP: 0000000000700020 R08: 0000000000000018 R09: 0000000000000000 [ 32.502677] R10: 0000000020000100 R11: 0000000000000246 R12: 0000000000000000 [ 32.509932] R13: 000000000080fe4f R14: 00007fb627a949c0 R15: 0000000000002710