[....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[ 18.979919] random: sshd: uninitialized urandom read (32 bytes read, 32 bits of entropy available) [?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 20.877726] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available) [ 21.092870] random: sshd: uninitialized urandom read (32 bytes read, 34 bits of entropy available) [ 22.072371] random: sshd: uninitialized urandom read (32 bytes read, 120 bits of entropy available) [ 22.226601] random: sshd: uninitialized urandom read (32 bytes read, 122 bits of entropy available) Warning: Permanently added '10.128.10.37' (ECDSA) to the list of known hosts. [ 27.775730] random: sshd: uninitialized urandom read (32 bytes read, 128 bits of entropy available) 2018/04/14 07:36:33 parsed 1 programs 2018/04/14 07:36:33 executed programs: 0 [ 28.234806] IPVS: Creating netns size=2552 id=1 [ 28.262421] IPVS: Creating netns size=2552 id=2 [ 28.288227] IPVS: Creating netns size=2552 id=3 [ 28.344846] IPVS: Creating netns size=2552 id=4 [ 28.364258] IPVS: stopping backup sync thread 3784 ... [ 28.374881] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.385406] IPVS: stopping backup sync thread 3789 ... [ 28.385780] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.386702] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.409326] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.425468] IPVS: Creating netns size=2552 id=5 [ 28.466371] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.475018] IPVS: stopping backup sync thread 3802 ... [ 28.482315] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.486221] IPVS: stopping backup sync thread 3791 ... [ 28.487253] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.509017] IPVS: Creating netns size=2552 id=6 [ 28.539928] IPVS: stopping backup sync thread 3795 ... [ 28.545478] IPVS: stopping backup sync thread 3821 ... [ 28.553348] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 0, id = 0 [ 28.562578] [ 28.564205] ============================================= [ 28.569716] [ INFO: possible recursive locking detected ] [ 28.575222] 4.4.125-g38f41ec #21 Not tainted [ 28.579594] --------------------------------------------- [ 28.585105] syz-executor1/3816 is trying to acquire lock: [ 28.590695] (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 28.598599] [ 28.598599] but task is already holding lock: [ 28.604540] (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 28.612446] [ 28.612446] other info that might help us debug this: [ 28.619087] Possible unsafe locking scenario: [ 28.619087] [ 28.625117] CPU0 [ 28.627675] ---- [ 28.630235] lock(rtnl_mutex); [ 28.633714] lock(rtnl_mutex); [ 28.637190] [ 28.637190] *** DEADLOCK *** [ 28.637190] [ 28.643213] May be due to missing lock nesting notation [ 28.643213] [ 28.650116] 2 locks held by syz-executor1/3816: [ 28.654748] #0: (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 28.663187] #1: (ipvs->sync_mutex){+.+.+.}, at: [] do_ip_vs_set_ctl+0x8d3/0xba0 [ 28.672926] [ 28.672926] stack backtrace: [ 28.677392] CPU: 1 PID: 3816 Comm: syz-executor1 Not tainted 4.4.125-g38f41ec #21 [ 28.684977] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.694314] 0000000000000000 db49b3ef53127586 ffff8800ad0c7470 ffffffff81d067bd [ 28.702278] ffffffff85170f60 ffffffff85170f60 ffff8800ad2fb000 dffffc0000000000 [ 28.710252] ffff8800ad2fb8e0 ffff8800ad0c7620 ffffffff81238c40 ffffffff84a258a8 [ 28.718233] Call Trace: [ 28.720801] [] dump_stack+0xc1/0x124 [ 28.726134] [] __lock_acquire+0x1350/0x4b50 [ 28.732072] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.739052] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.746039] [] ? __lock_is_held+0xa1/0xf0 [ 28.751807] [] lock_acquire+0x15e/0x460 [ 28.757406] [] ? rtnl_lock+0x17/0x20 [ 28.762749] [] ? rtnl_lock+0x17/0x20 [ 28.768087] [] mutex_lock_nested+0xbb/0x850 [ 28.774024] [] ? rtnl_lock+0x17/0x20 [ 28.779370] [] ? qtaguid_untag+0x495/0x690 [ 28.785222] [] ? __ww_mutex_lock+0x14f0/0x14f0 [ 28.791419] [] ? _raw_spin_unlock_bh+0x30/0x40 [ 28.797620] [] ? qtaguid_untag+0x322/0x690 [ 28.803472] [] rtnl_lock+0x17/0x20 [ 28.808630] [] ip_mc_drop_socket+0x88/0x230 [ 28.814567] [] inet_release+0x5b/0x1d0 [ 28.820074] [] sock_release+0x8d/0x1e0 [ 28.825582] [] start_sync_thread+0x196a/0x1f50 [ 28.831780] [] ? _raw_spin_unlock_irq+0x38/0x50 [ 28.838076] [] ? finish_task_switch+0x1bb/0x660 [ 28.844363] [] ? ip_vs_proc_sync_conn+0xb10/0xb10 [ 28.850833] [] ? ip_vs_sync_conn+0x2980/0x2980 [ 28.857036] [] ? mark_held_locks+0xaf/0x100 [ 28.862977] [] ? mutex_lock_nested+0x5d4/0x850 [ 28.869175] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.875992] [] ? mutex_lock_nested+0x560/0x850 [ 28.882208] [] ? do_ip_vs_set_ctl+0x8d3/0xba0 [ 28.888332] [] ? __ww_mutex_lock+0x14f0/0x14f0 [ 28.894540] [] ? memcpy+0x45/0x50 [ 28.899616] [] do_ip_vs_set_ctl+0x8e5/0xba0 [ 28.905570] [] ? futex_wake+0x153/0x450 [ 28.911161] [] ? ip_vs_genl_set_cmd+0x9a0/0x9a0 [ 28.917448] [] ? mark_held_locks+0xaf/0x100 [ 28.923387] [] ? mutex_lock_nested+0x5d4/0x850 [ 28.929585] [] ? __mutex_unlock_slowpath+0x208/0x3b0 [ 28.936305] [] ? __ww_mutex_lock_interruptible+0x14d0/0x14d0 [ 28.944501] [] ? sock_has_perm+0x1c1/0x400 [ 28.950360] [] ? mutex_unlock+0x9/0x10 [ 28.955871] [] ? nf_sockopt_find.constprop.0+0x1a7/0x220 [ 28.962968] [] compat_nf_setsockopt+0xfa/0x130 [ 28.969262] [] compat_ip_setsockopt+0x8b/0xd0 [ 28.975374] [] inet_csk_compat_setsockopt+0x95/0x120 [ 28.982102] [] ? ip_setsockopt+0xa0/0xa0 [ 28.987783] [] compat_tcp_setsockopt+0x3d/0x70 [ 28.993992] [] compat_sock_common_setsockopt+0xb2/0x140 [ 29.000976] [] ? tcp_setsockopt+0xd0/0xd0 [ 29.006746] [] compat_SyS_setsockopt+0x149/0x290 [ 29.013127] [] ? sock_common_setsockopt+0xd0/0xd0 [ 29.019589] [] ? scm_detach_fds_compat+0x3c0/0x3c0 [ 29.026138] [] ? do_fast_syscall_32+0xd7/0x8a0 [ 29.032336] [] ? scm_detach_fds_compat+0x3c0/0x3c0 [ 29.038884] [] do_fast_syscall_32+0x321/0x8a0 [ 29.044998] [] sysenter_flags_fixed+0xd/0x17 [ 29.057208] IPVS: Creating netns size=2552 id=7 [ 29.859022] IPVS: stopping backup sync thread 3806 ... [ 29.886357] IPVS: stopping backup sync thread 3811 ... [ 29.966351] IPVS: stopping backup sync thread 3824 ... [ 30.040828] random: nonblocking pool is initialized