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 '10.128.10.34' (ECDSA) to the list of known hosts. 2018/04/24 04:22:47 parsed 1 programs 2018/04/24 04:22:47 executed programs: 0 syzkaller login: [ 26.788216] IPVS: Creating netns size=2536 id=1 [ 26.810977] IPVS: stopping backup sync thread 3834 ... [ 26.815986] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 26.825201] IPVS: Creating netns size=2536 id=2 [ 26.825409] IPVS: Unknown mcast interface: ipddp0 [ 26.825838] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 26.825866] IPVS: stopping backup sync thread 3838 ... [ 26.834553] IPVS: stopping backup sync thread 3841 ... [ 26.834643] IPVS: Unknown mcast interface: ipddp0 [ 26.835081] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 26.835103] IPVS: stopping backup sync thread 3843 ... [ 26.859205] IPVS: stopping backup sync thread 3848 ... [ 26.859273] IPVS: Unknown mcast interface: ipddp0 [ 26.859650] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 26.859674] IPVS: stopping backup sync thread 3850 ... [ 26.871088] IPVS: stopping backup sync thread 3854 ... [ 26.871195] IPVS: Unknown mcast interface: ipddp0 [ 26.871843] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 26.871898] IPVS: stopping backup sync thread 3856 ... [ 26.886060] IPVS: stopping backup sync thread 3859 ... [ 26.886149] IPVS: Unknown mcast interface: ipddp0 [ 26.886641] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 26.886673] IPVS: stopping backup sync thread 3861 ... [ 26.903760] IPVS: stopping backup sync thread 3865 ... [ 26.903850] IPVS: Unknown mcast interface: ipddp0 [ 26.904379] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 26.904409] IPVS: stopping backup sync thread 3867 ... [ 26.923425] IPVS: stopping backup sync thread 3872 ... [ 26.923513] IPVS: Unknown mcast interface: ipddp0 [ 26.924060] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 26.924097] IPVS: stopping backup sync thread 3874 ... [ 26.937127] IPVS: stopping backup sync thread 3878 ... [ 26.937218] IPVS: Unknown mcast interface: ipddp0 [ 26.937699] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 26.937745] IPVS: stopping backup sync thread 3880 ... [ 26.950654] IPVS: stopping backup sync thread 3883 ... [ 26.950754] IPVS: Unknown mcast interface: ipddp0 [ 26.951359] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 26.951393] IPVS: stopping backup sync thread 3885 ... [ 26.962304] IPVS: stopping backup sync thread 3889 ... [ 26.962395] IPVS: Unknown mcast interface: ipddp0 [ 26.962889] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 26.962942] IPVS: stopping backup sync thread 3891 ... [ 27.085503] IPVS: stopping backup sync thread 3898 ... [ 27.087802] IPVS: Creating netns size=2536 id=3 [ 27.097960] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.106892] IPVS: Unknown mcast interface: ipddp0 [ 27.113506] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.114449] IPVS: stopping backup sync thread 3906 ... [ 27.122124] IPVS: stopping backup sync thread 3909 ... [ 27.122224] IPVS: Unknown mcast interface: ipddp0 [ 27.122751] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.122836] IPVS: stopping backup sync thread 3911 ... [ 27.125193] IPVS: Creating netns size=2536 id=4 [ 27.153336] IPVS: stopping backup sync thread 3917 ... [ 27.153441] IPVS: Unknown mcast interface: ipddp0 [ 27.154067] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.154104] IPVS: stopping backup sync thread 3919 ... [ 27.172533] IPVS: Creating netns size=2536 id=5 [ 27.184622] IPVS: stopping backup sync thread 3927 ... [ 27.184819] IPVS: Unknown mcast interface: ipddp0 [ 27.192523] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.195762] IPVS: stopping backup sync thread 3931 ... [ 27.201435] IPVS: Creating netns size=2536 id=6 [ 27.217731] IPVS: stopping backup sync thread 3937 ... [ 27.221197] IPVS: Unknown mcast interface: ipddp0 [ 27.223281] IPVS: stopping backup sync thread 3940 ... [ 27.249645] IPVS: stopping backup sync thread 3948 ... [ 27.249742] IPVS: Unknown mcast interface: ipddp0 [ 27.250281] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.251194] IPVS: stopping backup sync thread 3950 ... [ 27.257715] IPVS: Creating netns size=2536 id=7 [ 27.286423] IPVS: stopping backup sync thread 3957 ... [ 27.286515] IPVS: Unknown mcast interface: ipddp0 [ 27.287002] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.287047] IPVS: stopping backup sync thread 3959 ... [ 27.303742] IPVS: Creating netns size=2536 id=8 [ 27.334086] IPVS: stopping backup sync thread 3968 ... [ 27.334175] IPVS: Unknown mcast interface: ipddp0 [ 27.334652] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.334695] IPVS: stopping backup sync thread 3970 ... [ 27.374356] IPVS: stopping backup sync thread 3988 ... [ 27.379888] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.380708] IPVS: stopping backup sync thread 3989 ... [ 27.380822] IPVS: Unknown mcast interface: ipddp0 [ 27.382581] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.382769] IPVS: stopping backup sync thread 3992 ... [ 27.382871] IPVS: Unknown mcast interface: ipddp0 [ 27.383705] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.383741] IPVS: stopping backup sync thread 3994 ... [ 27.384308] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.384651] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.384757] IPVS: stopping backup sync thread 3997 ... [ 27.389862] IPVS: stopping backup sync thread 3995 ... [ 27.389931] IPVS: stopping backup sync thread 3996 ... [ 27.391788] IPVS: stopping backup sync thread 3991 ... [ 27.392683] [ 27.392685] ============================================= [ 27.392687] [ INFO: possible recursive locking detected ] [ 27.392692] 4.9.95-g142d4b5 #7 Not tainted [ 27.392693] --------------------------------------------- [ 27.392697] syz-executor5/3984 is trying to acquire lock: [ 27.392719] (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 27.392720] but task is already holding lock: [ 27.392730] (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 27.392732] other info that might help us debug this: [ 27.392734] Possible unsafe locking scenario: [ 27.392734] [ 27.392735] CPU0 [ 27.392737] ---- [ 27.392740] lock(rtnl_mutex); [ 27.392744] lock(rtnl_mutex); [ 27.392745] [ 27.392745] *** DEADLOCK *** [ 27.392745] [ 27.392746] May be due to missing lock nesting notation [ 27.392746] [ 27.392750] 2 locks held by syz-executor5/3984: [ 27.392761] #0: (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 27.392774] #1: (ipvs->sync_mutex){+.+.+.}, at: [] do_ip_vs_set_ctl+0x90d/0xbd0 [ 27.392775] [ 27.392775] stack backtrace: [ 27.392782] CPU: 1 PID: 3984 Comm: syz-executor5 Not tainted 4.9.95-g142d4b5 #7 [ 27.392785] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.392797] ffff8801bc95f470 ffffffff81eb0f89 ffffffff8539d290 ffffffff8539d290 [ 27.392805] ffffffff8539d290 ffff8801c99120e8 e14e6969a98f414d ffff8801bc95f630 [ 27.392814] ffffffff814259ef ffffffff84c98ca0 ffffffff84feedf8 ffffffff84c98ca4 [ 27.392816] Call Trace: [ 27.392826] [] dump_stack+0xc1/0x128 [ 27.392838] [] __lock_acquire.cold.59+0x166/0x5f8 [ 27.392850] [] ? debug_check_no_locks_freed+0x210/0x210 [ 27.392857] [] ? __lock_is_held+0xa2/0xf0 [ 27.392864] [] lock_acquire+0x130/0x3e0 [ 27.392870] [] ? rtnl_lock+0x17/0x20 [ 27.392877] [] ? rtnl_lock+0x17/0x20 [ 27.392886] [] mutex_lock_nested+0xc0/0x870 [ 27.392892] [] ? rtnl_lock+0x17/0x20 [ 27.392906] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 27.392913] [] ? qtaguid_untag+0x41a/0x620 [ 27.392920] [] ? mutex_trylock+0x3e0/0x3e0 [ 27.392927] [] ? _raw_spin_unlock_bh+0x30/0x40 [ 27.392934] [] ? qtaguid_untag+0x31e/0x620 [ 27.392940] [] ? __lock_is_held+0xa2/0xf0 [ 27.392947] [] rtnl_lock+0x17/0x20 [ 27.392955] [] ip_mc_drop_socket+0x8c/0x230 [ 27.392962] [] inet_release+0x5b/0x1d0 [ 27.392972] [] sock_release+0x96/0x1c0 [ 27.392979] [] start_sync_thread+0xa0e/0x1ea0 [ 27.392988] [] ? ip_vs_proc_sync_conn+0x952/0x952 [ 27.392995] [] ? ip_vs_sync_conn+0x2a90/0x2a90 [ 27.393001] [] ? mark_held_locks+0xc7/0x130 [ 27.393008] [] ? mutex_lock_nested+0x572/0x870 [ 27.393015] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 27.393022] [] ? mutex_lock_nested+0x596/0x870 [ 27.393028] [] ? do_ip_vs_set_ctl+0x90d/0xbd0 [ 27.393034] [] ? mutex_trylock+0x3e0/0x3e0 [ 27.393042] [] ? memcpy+0x45/0x50 [ 27.393048] [] do_ip_vs_set_ctl+0x91f/0xbd0 [ 27.393057] [] ? get_futex_key+0x1090/0x1090 [ 27.393064] [] ? ip_vs_genl_set_cmd+0x9c0/0x9c0 [ 27.393071] [] ? mutex_lock_nested+0x572/0x870 [ 27.393078] [] ? __mutex_unlock_slowpath+0x221/0x3c0 [ 27.393085] [] ? __ww_mutex_lock+0x14c0/0x14c0 [ 27.393093] [] ? sock_has_perm+0x1c2/0x3e0 [ 27.393100] [] ? mutex_unlock+0x9/0x10 [ 27.393109] [] ? nf_sockopt_find.constprop.0+0x1b1/0x230 [ 27.393116] [] compat_nf_setsockopt+0x10d/0x130 [ 27.393123] [] compat_ip_setsockopt+0xa7/0xe0 [ 27.393130] [] inet_csk_compat_setsockopt+0x97/0x120 [ 27.393136] [] ? ip_setsockopt+0xb0/0xb0 [ 27.393143] [] compat_tcp_setsockopt+0x3d/0x70 [ 27.393150] [] compat_sock_common_setsockopt+0xb4/0x150 [ 27.393157] [] ? tcp_setsockopt+0xe0/0xe0 [ 27.393165] [] compat_SyS_setsockopt+0x14c/0x2a0 [ 27.393171] [] ? sock_common_setsockopt+0xe0/0xe0 [ 27.393177] [] ? scm_detach_fds_compat+0x3b0/0x3b0 [ 27.393185] [] ? do_fast_syscall_32+0xcf/0x870 [ 27.393192] [] ? scm_detach_fds_compat+0x3b0/0x3b0 [ 27.393198] [] do_fast_syscall_32+0x2f7/0x870 [ 27.393205] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.393212] [] entry_SYSENTER_compat+0x90/0xa2 [ 27.393338] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 27.393442] IPVS: stopping backup sync thread 3998 ...