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 '10.128.0.49' (ECDSA) to the list of known hosts. syzkaller login: [ 41.490770] IPVS: Creating netns size=2536 id=1 executing program executing program executing program executing program [ 41.512592] IPVS: Creating netns size=2536 id=2 [ 41.523983] IPVS: Creating netns size=2536 id=3 [ 41.542365] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 41.543559] IPVS: stopping backup sync thread 3795 ... executing program executing program executing program executing program executing program executing program executing program executing program [ 41.559829] IPVS: stopping backup sync thread 3803 ... [ 41.560652] IPVS: stopping backup sync thread 3806 ... [ 41.561546] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 41.564668] IPVS: stopping backup sync thread 3810 ... [ 41.566082] IPVS: Creating netns size=2536 id=4 [ 41.574839] IPVS: stopping backup sync thread 3815 ... [ 41.575703] IPVS: stopping backup sync thread 3820 ... [ 41.582213] IPVS: stopping backup sync thread 3825 ... executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 41.587215] IPVS: stopping backup sync thread 3830 ... [ 41.589156] IPVS: stopping backup sync thread 3833 ... [ 41.600609] IPVS: Creating netns size=2536 id=5 [ 41.603600] IPVS: stopping backup sync thread 3842 ... [ 41.609806] IPVS: stopping backup sync thread 3846 ... [ 41.613966] IPVS: stopping backup sync thread 3850 ... [ 41.620075] IPVS: stopping backup sync thread 3855 ... [ 41.620500] IPVS: stopping backup sync thread 3859 ... executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 41.620944] IPVS: stopping backup sync thread 3861 ... [ 41.626281] IPVS: stopping backup sync thread 3867 ... [ 41.630965] IPVS: stopping backup sync thread 3871 ... [ 41.631524] IPVS: stopping backup sync thread 3875 ... [ 41.636871] IPVS: Creating netns size=2536 id=6 [ 41.643876] IPVS: stopping backup sync thread 3880 ... [ 41.649443] IPVS: stopping backup sync thread 3885 ... executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 41.657091] IPVS: stopping backup sync thread 3891 ... [ 41.661583] IPVS: stopping backup sync thread 3899 ... [ 41.662070] IPVS: stopping backup sync thread 3901 ... [ 41.662320] IPVS: stopping backup sync thread 3902 ... [ 41.667361] IPVS: Creating netns size=2536 id=7 [ 41.675810] IPVS: stopping backup sync thread 3910 ... [ 41.677634] IPVS: stopping backup sync thread 3913 ... [ 41.679048] IPVS: stopping backup sync thread 3917 ... executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 41.679701] IPVS: Creating netns size=2536 id=8 [ 41.686049] IPVS: stopping backup sync thread 3923 ... [ 41.691716] IPVS: stopping backup sync thread 3926 ... [ 41.695617] IPVS: stopping backup sync thread 3931 ... [ 41.697073] IPVS: stopping backup sync thread 3936 ... [ 41.699064] IPVS: stopping backup sync thread 3938 ... [ 41.708880] IPVS: stopping backup sync thread 3947 ... [ 41.709575] IPVS: stopping backup sync thread 3950 ... executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 41.725169] IPVS: stopping backup sync thread 3961 ... [ 41.726880] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 41.727176] IPVS: stopping backup sync thread 3968 ... [ 41.728365] IPVS: stopping backup sync thread 3969 ... [ 41.728846] IPVS: stopping backup sync thread 3972 ... [ 41.731695] IPVS: stopping backup sync thread 3965 ... [ 41.737696] IPVS: stopping backup sync thread 3975 ... [ 41.745320] IPVS: stopping backup sync thread 3984 ... [ 41.751058] IPVS: stopping backup sync thread 3990 ... [ 41.753949] IPVS: stopping backup sync thread 3995 ... [ 41.755122] IPVS: stopping backup sync thread 3998 ... [ 41.757294] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 41.757575] IPVS: stopping backup sync thread 4004 ... [ 41.759013] IPVS: stopping backup sync thread 4005 ... [ 41.759526] IPVS: stopping backup sync thread 4008 ... [ 41.763285] IPVS: stopping backup sync thread 4002 ... [ 41.765164] IPVS: stopping backup sync thread 4015 ... [ 41.771276] IPVS: stopping backup sync thread 4021 ... [ 41.774533] IPVS: stopping backup sync thread 4025 ... [ 41.776641] IPVS: stopping backup sync thread 4026 ... [ 41.777202] IPVS: stopping backup sync thread 4032 ... [ 41.778427] IPVS: stopping backup sync thread 4033 ... [ 41.783481] IPVS: stopping backup sync thread 4039 ... [ 41.785476] IPVS: stopping backup sync thread 4042 ... [ 41.793993] IPVS: stopping backup sync thread 4048 ... [ 41.794419] IPVS: stopping backup sync thread 4054 ... [ 41.799987] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 41.800182] IPVS: stopping backup sync thread 4057 ... [ 41.802079] IPVS: stopping backup sync thread 4061 ... [ 41.802505] IPVS: stopping backup sync thread 4064 ... [ 41.803091] IPVS: stopping backup sync thread 4066 ... [ 41.803348] IPVS: stopping backup sync thread 4068 ... [ 41.813283] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 41.813391] IPVS: stopping backup sync thread 4073 ... [ 41.815038] IPVS: stopping backup sync thread 4080 ... [ 41.817841] IPVS: stopping backup sync thread 4087 ... [ 41.818480] IPVS: stopping backup sync thread 4090 ... [ 41.821902] IPVS: stopping backup sync thread 4093 ... [ 41.823631] IPVS: stopping backup sync thread 4096 ... [ 41.828153] IPVS: stopping backup sync thread 4101 ... [ 41.830976] IPVS: stopping backup sync thread 4105 ... [ 41.836586] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 41.836938] IPVS: stopping backup sync thread 4106 ... [ 41.837210] IPVS: stopping backup sync thread 4112 ... [ 41.839698] IPVS: stopping backup sync thread 4116 ... [ 41.840526] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 41.844440] IPVS: stopping backup sync thread 4115 ... [ 41.847323] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 41.847922] IPVS: stopping backup sync thread 4127 ... [ 41.848917] IPVS: stopping backup sync thread 4130 ... [ 41.850342] IPVS: stopping backup sync thread 4132 ... [ 41.852185] IPVS: stopping backup sync thread 4123 ... [ 41.852984] [ 41.852985] ============================================= [ 41.852989] [ INFO: possible recursive locking detected ] [ 41.852993] 4.9.94-g8683408 #3 Not tainted [ 41.852994] --------------------------------------------- [ 41.852996] syzkaller455064/4108 is trying to acquire lock: [ 41.853015] (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 41.853016] but task is already holding lock: [ 41.853022] (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 41.853023] other info that might help us debug this: [ 41.853024] Possible unsafe locking scenario: [ 41.853024] [ 41.853025] CPU0 [ 41.853026] ---- [ 41.853029] lock(rtnl_mutex); [ 41.853031] lock(rtnl_mutex); [ 41.853032] [ 41.853032] *** DEADLOCK *** [ 41.853032] [ 41.853033] May be due to missing lock nesting notation [ 41.853033] [ 41.853035] 2 locks held by syzkaller455064/4108: [ 41.853042] #0: (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 41.853053] #1: (ipvs->sync_mutex){+.+.+.}, at: [] do_ip_vs_set_ctl+0x90d/0xbd0 [ 41.853054] [ 41.853054] stack backtrace: [ 41.853058] CPU: 1 PID: 4108 Comm: syzkaller455064 Not tainted 4.9.94-g8683408 #3 [ 41.853061] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 41.853068] ffff8801d86e7480 ffffffff81d9b509 ffffffff85373290 ffffffff85373290 [ 41.853073] ffffffff85373290 ffff8801d8b3e8e8 5011931c506d6302 ffff8801d86e7640 [ 41.853078] ffffffff814258ef ffffffff84c6eca0 ffffffff84fbe078 ffffffff84c6eca4 [ 41.853079] Call Trace: [ 41.853087] [] dump_stack+0xc1/0x128 [ 41.853095] [] __lock_acquire.cold.59+0x166/0x5f8 [ 41.853104] [] ? debug_check_no_locks_freed+0x210/0x210 [ 41.853108] [] ? __lock_is_held+0xa2/0xf0 [ 41.853112] [] lock_acquire+0x130/0x3e0 [ 41.853116] [] ? rtnl_lock+0x17/0x20 [ 41.853121] [] ? rtnl_lock+0x17/0x20 [ 41.853129] [] mutex_lock_nested+0xc0/0x870 [ 41.853133] [] ? rtnl_lock+0x17/0x20 [ 41.853137] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 41.853143] [] ? qtaguid_untag+0x41a/0x620 [ 41.853147] [] ? mutex_trylock+0x3e0/0x3e0 [ 41.853152] [] ? _raw_spin_unlock_bh+0x30/0x40 [ 41.853155] [] ? qtaguid_untag+0x31e/0x620 [ 41.853159] [] ? __lock_is_held+0xa2/0xf0 [ 41.853163] [] rtnl_lock+0x17/0x20 [ 41.853171] [] ip_mc_drop_socket+0x8c/0x230 [ 41.853175] [] inet_release+0x5b/0x1d0 [ 41.853182] [] sock_release+0x96/0x1c0 [ 41.853186] [] start_sync_thread+0xa0e/0x1ea0 [ 41.853193] [] ? ip_vs_proc_sync_conn+0x952/0x952 [ 41.853197] [] ? ip_vs_sync_conn+0x2a90/0x2a90 [ 41.853201] [] ? mark_held_locks+0xc7/0x130 [ 41.853206] [] ? mutex_lock_nested+0x572/0x870 [ 41.853210] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 41.853214] [] ? mutex_lock_nested+0x596/0x870 [ 41.853218] [] ? do_ip_vs_set_ctl+0x90d/0xbd0 [ 41.853222] [] ? mutex_trylock+0x3e0/0x3e0 [ 41.853228] [] ? memcpy+0x45/0x50 [ 41.853232] [] do_ip_vs_set_ctl+0x91f/0xbd0 [ 41.853236] [] ? ip_vs_genl_set_cmd+0x9c0/0x9c0 [ 41.853245] [] ? mutex_lock_nested+0x572/0x870 [ 41.853249] [] ? __mutex_unlock_slowpath+0x221/0x3c0 [ 41.853254] [] ? __ww_mutex_lock+0x14c0/0x14c0 [ 41.853259] [] ? sock_has_perm+0x292/0x3e0 [ 41.853263] [] ? mutex_unlock+0x9/0x10 [ 41.853270] [] ? nf_sockopt_find.constprop.0+0x1b1/0x230 [ 41.853274] [] nf_setsockopt+0x6d/0xc0 [ 41.853280] [] ip_setsockopt+0x9a/0xb0 [ 41.853286] [] tcp_setsockopt+0x88/0xe0 [ 41.853290] [] sock_common_setsockopt+0x9a/0xe0 [ 41.853294] [] SyS_setsockopt+0x166/0x260 [ 41.853298] [] ? SyS_recv+0x40/0x40 [ 41.853306] [] ? __do_page_fault+0x183/0xd50 [ 41.853310] [] ? move_addr_to_kernel+0x50/0x50 [ 41.853317] [] ? do_syscall_64+0x48/0x490 [ 41.853320] [] ? SyS_recv+0x40/0x40 [ 41.853324] [] do_syscall_64+0x1a6/0x490 [ 41.853329] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb