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 '10.128.0.54' (ECDSA) to the list of known hosts. 2018/03/29 23:12:24 parsed 1 programs 2018/03/29 23:12:24 executed programs: 0 syzkaller login: [ 43.641509] IPVS: ftp: loaded support on port[0] = 21 [ 43.673542] IPVS: ftp: loaded support on port[0] = 21 [ 43.703719] IPVS: ftp: loaded support on port[0] = 21 [ 43.718432] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 43.718704] [ 43.728510] ============================================ [ 43.733928] WARNING: possible recursive locking detected [ 43.739349] 4.16.0-rc7+ #5 Not tainted [ 43.743203] -------------------------------------------- [ 43.748620] syz-executor4/4448 is trying to acquire lock: [ 43.754134] (rtnl_mutex){+.+.}, at: [<00000000814b9036>] rtnl_lock+0x17/0x20 [ 43.761391] [ 43.761391] but task is already holding lock: [ 43.767353] (rtnl_mutex){+.+.}, at: [<00000000814b9036>] rtnl_lock+0x17/0x20 [ 43.774615] [ 43.774615] other info that might help us debug this: [ 43.781272] Possible unsafe locking scenario: [ 43.781272] [ 43.787313] CPU0 [ 43.790571] ---- [ 43.793122] lock(rtnl_mutex); [ 43.796378] lock(rtnl_mutex); [ 43.799625] [ 43.799625] *** DEADLOCK *** [ 43.799625] [ 43.805650] May be due to missing lock nesting notation [ 43.805650] [ 43.813155] 2 locks held by syz-executor4/4448: [ 43.817894] #0: (rtnl_mutex){+.+.}, at: [<00000000814b9036>] rtnl_lock+0x17/0x20 [ 43.825582] #1: (ipvs->sync_mutex){+.+.}, at: [<00000000cb780d64>] do_ip_vs_set_ctl+0x10f8/0x1cc0 [ 43.834754] [ 43.834754] stack backtrace: [ 43.839229] CPU: 0 PID: 4448 Comm: syz-executor4 Not tainted 4.16.0-rc7+ #5 [ 43.846300] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.855711] Call Trace: [ 43.858290] dump_stack+0x194/0x24d [ 43.861888] ? arch_local_irq_restore+0x53/0x53 [ 43.866529] __lock_acquire+0xe8f/0x3e00 [ 43.870564] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 43.875733] ? _raw_spin_unlock+0x22/0x30 [ 43.879851] ? __perf_event_task_sched_in+0x200/0xc20 [ 43.885089] ? __lock_acquire+0x664/0x3e00 [ 43.889294] ? print_irqtrace_events+0x270/0x270 [ 43.894195] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 43.899352] ? lock_downgrade+0x980/0x980 [ 43.903475] ? mark_held_locks+0xaf/0x100 [ 43.907596] ? _raw_spin_unlock_irq+0x27/0x70 [ 43.912062] ? trace_hardirqs_off+0x10/0x10 [ 43.916356] ? trace_hardirqs_on+0xd/0x10 [ 43.920476] ? _raw_spin_unlock_irq+0x27/0x70 [ 43.924942] ? finish_task_switch+0x1c1/0x7e0 [ 43.929415] ? finish_task_switch+0x182/0x7e0 [ 43.933879] ? copy_overflow+0x20/0x20 [ 43.937736] lock_acquire+0x1d5/0x580 [ 43.941507] ? lock_acquire+0x1d5/0x580 [ 43.945453] ? rtnl_lock+0x17/0x20 [ 43.948964] ? lock_release+0xa40/0xa40 [ 43.952919] ? check_same_owner+0x320/0x320 [ 43.957212] ? rcu_note_context_switch+0x710/0x710 [ 43.962112] ? __might_sleep+0x95/0x190 [ 43.966055] ? rtnl_lock+0x17/0x20 [ 43.969564] __mutex_lock+0x16f/0x1a80 [ 43.973420] ? rtnl_lock+0x17/0x20 [ 43.977101] ? wait_for_completion_killable+0x63e/0x820 [ 43.982434] ? lock_downgrade+0x980/0x980 [ 43.986552] ? rtnl_lock+0x17/0x20 [ 43.990064] ? mutex_lock_io_nested+0x1900/0x1900 [ 43.994877] ? mark_held_locks+0xaf/0x100 [ 43.998997] ? _raw_spin_unlock_irq+0x27/0x70 [ 44.003461] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 44.008444] ? trace_hardirqs_on+0xd/0x10 [ 44.012562] ? _raw_spin_unlock_irq+0x27/0x70 [ 44.017025] ? wait_for_completion_killable+0x63e/0x820 [ 44.022379] ? wait_for_completion_interruptible_timeout+0x820/0x820 [ 44.028849] ? lock_downgrade+0x980/0x980 [ 44.032968] ? lock_release+0xa40/0xa40 [ 44.036924] ? __kthread_create_on_node+0x127/0x480 [ 44.041912] ? do_raw_spin_trylock+0x190/0x190 [ 44.046465] ? wake_up_q+0xe0/0xe0 [ 44.049976] ? SyS_setsockopt+0x189/0x360 [ 44.054097] ? do_syscall_64+0x281/0x940 [ 44.058128] ? entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 44.063465] ? __kthread_create_on_node+0x36e/0x480 [ 44.068450] ? print_irqtrace_events+0x270/0x270 [ 44.073176] ? kthread_park+0x130/0x130 [ 44.077117] ? lock_release+0xa40/0xa40 [ 44.081065] ? __lock_is_held+0xb6/0x140 [ 44.085101] mutex_lock_nested+0x16/0x20 [ 44.089135] ? mutex_lock_nested+0x16/0x20 [ 44.093339] rtnl_lock+0x17/0x20 [ 44.096679] ip_mc_drop_socket+0x88/0x230 [ 44.100808] inet_release+0x4e/0x1c0 [ 44.104494] sock_release+0x8d/0x1e0 [ 44.108177] start_sync_thread+0x2213/0x2b70 [ 44.112554] ? do_ip_vs_set_ctl+0x10f8/0x1cc0 [ 44.117019] ? ip_vs_process_message_v0+0x870/0x870 [ 44.122007] ? ip_vs_sync_conn+0x3950/0x3950 [ 44.126392] ? trace_hardirqs_off+0x10/0x10 [ 44.130683] ? lock_downgrade+0x980/0x980 [ 44.134813] ? find_held_lock+0x35/0x1d0 [ 44.138846] ? __might_fault+0x110/0x1d0 [ 44.142883] ? lock_release+0xa40/0xa40 [ 44.146839] ? check_same_owner+0x320/0x320 [ 44.151133] ? module_unload_free+0x5b0/0x5b0 [ 44.155600] ? __might_sleep+0x95/0x190 [ 44.159552] do_ip_vs_set_ctl+0x1139/0x1cc0 [ 44.163844] ? do_ip_vs_set_ctl+0x1139/0x1cc0 [ 44.168331] ? find_held_lock+0x35/0x1d0 [ 44.172382] ? ip_vs_genl_dump_services+0x440/0x440 [ 44.177369] ? nf_sockopt_find.constprop.0+0x1a7/0x220 [ 44.182625] ? lock_downgrade+0x980/0x980 [ 44.186745] ? __fget+0x342/0x5b0 [ 44.190176] ? lock_downgrade+0x980/0x980 [ 44.194305] ? lock_release+0xa40/0xa40 [ 44.198251] ? __lock_is_held+0xb6/0x140 [ 44.202287] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 44.207111] ? wait_for_completion+0x770/0x770 [ 44.211664] ? __fget+0x36b/0x5b0 [ 44.215225] ? module_unload_free+0x5b0/0x5b0 [ 44.219694] ? iterate_fd+0x3f0/0x3f0 [ 44.223469] ? _raw_spin_unlock_irqrestore+0x31/0xc0 [ 44.228547] ? mutex_unlock+0xd/0x10 [ 44.232252] nf_setsockopt+0x67/0xc0 [ 44.235937] ? nf_setsockopt+0x67/0xc0 [ 44.239799] ip_setsockopt+0x97/0xa0 [ 44.243485] udp_setsockopt+0x45/0x80 [ 44.247255] ipv6_setsockopt+0xa0/0x130 [ 44.251205] udpv6_setsockopt+0x45/0x80 [ 44.255155] sock_common_setsockopt+0x95/0xd0 [ 44.259621] SyS_setsockopt+0x189/0x360 [ 44.263578] ? SyS_recv+0x40/0x40 [ 44.267006] ? move_addr_to_kernel+0x60/0x60 [ 44.271388] ? do_syscall_64+0xb7/0x940 [ 44.275350] ? SyS_recv+0x40/0x40 [ 44.278788] do_syscall_64+0x281/0x940 [ 44.282647] ? __do_page_fault+0xc90/0xc90 [ 44.286853] ? _raw_spin_unlock_irq+0x27/0x70 [ 44.291318] ? finish_task_switch+0x1c1/0x7e0 [ 44.295785] ? syscall_return_slowpath+0x550/0x550 [ 44.300684] ? syscall_return_slowpath+0x2ac/0x550 [ 44.305584] ? prepare_exit_to_usermode+0x350/0x350 [ 44.310570] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7 [ 44.315905] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 44.320723] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 44.325881] RIP: 0033:0x4548b9 [ 44.329040] RSP: 002b:00007ff688819c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 [ 44.336736] RAX: ffffffffffffffda RBX: 00007ff68881a6d4 RCX: 00000000004548b9 [ 44.343977] RDX: 000000000000048b RSI: 0000000000000000 RDI: 0000000000000007 [ 44.351230] RBP: 000000000072bea0 R08: 0000000000000018 R09: 0000000000000000 [ 44.358473] R10: 0000000020000100 R11: 0000000000000246 R12: 00000000ffffffff [ 44.365715] R13: 000000000000051b R14: 00000000006f9b28 R15: 0000000000000000