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 '10.128.0.53' (ECDSA) to the list of known hosts. 2018/04/20 22:01:07 parsed 1 programs 2018/04/20 22:01:07 executed programs: 0 syzkaller login: [ 25.955338] IPVS: Creating netns size=2536 id=1 [ 25.978596] IPVS: Creating netns size=2536 id=2 [ 26.000358] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.008771] IPVS: stopping backup sync thread 3838 ... [ 26.009820] IPVS: Creating netns size=2536 id=3 [ 26.029483] IPVS: stopping backup sync thread 3846 ... [ 26.033462] IPVS: stopping backup sync thread 3852 ... [ 26.034603] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.049623] IPVS: Creating netns size=2536 id=4 [ 26.055972] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.067262] IPVS: stopping backup sync thread 3853 ... [ 26.079746] IPVS: stopping backup sync thread 3857 ... [ 26.087048] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.087643] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.097541] IPVS: Creating netns size=2536 id=5 [ 26.110822] IPVS: stopping backup sync thread 3873 ... [ 26.114865] IPVS: stopping backup sync thread 3871 ... [ 26.115425] IPVS: stopping backup sync thread 3869 ... [ 26.128317] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.132897] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.132913] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.144345] IPVS: stopping backup sync thread 3883 ... [ 26.147318] IPVS: Creating netns size=2536 id=6 [ 26.164508] IPVS: stopping backup sync thread 3889 ... [ 26.170145] IPVS: stopping backup sync thread 3885 ... [ 26.171597] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.183736] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.189329] IPVS: stopping backup sync thread 3910 ... [ 26.199819] IPVS: Creating netns size=2536 id=7 [ 26.208779] IPVS: stopping backup sync thread 3906 ... [ 26.208814] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.231396] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.231995] IPVS: Creating netns size=2536 id=8 [ 26.242181] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.257457] IPVS: stopping backup sync thread 3930 ... [ 26.275823] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.276498] IPVS: stopping backup sync thread 3938 ... [ 26.294805] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.307290] IPVS: stopping backup sync thread 3947 ... [ 26.315124] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.379032] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.401279] IPVS: stopping backup sync thread 3908 ... [ 26.402544] IPVS: stopping backup sync thread 3927 ... [ 26.403245] IPVS: stopping backup sync thread 3914 ... [ 26.403398] IPVS: stopping backup sync thread 3937 ... [ 26.404362] IPVS: stopping backup sync thread 3941 ... [ 26.406671] IPVS: stopping backup sync thread 3949 ... [ 26.408178] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.408605] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.408747] IPVS: stopping backup sync thread 3952 ... [ 26.408865] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.409046] IPVS: stopping backup sync thread 3925 ... [ 26.423430] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.425901] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.438705] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.451590] IPVS: stopping backup sync thread 3977 ... [ 26.451594] IPVS: stopping backup sync thread 3982 ... [ 26.451622] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.452481] IPVS: stopping backup sync thread 3974 ... [ 26.452904] IPVS: stopping backup sync thread 3976 ... [ 26.468050] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.482295] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.482516] IPVS: stopping backup sync thread 3991 ... [ 26.483083] IPVS: stopping backup sync thread 3978 ... [ 26.487126] IPVS: stopping backup sync thread 3994 ... [ 26.492750] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.492866] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.496577] IPVS: stopping backup sync thread 4009 ... [ 26.497667] IPVS: stopping backup sync thread 4015 ... [ 26.502793] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.511709] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.517318] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.526531] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.529067] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.733010] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.753591] IPVS: stopping backup sync thread 4031 ... [ 26.758212] IPVS: stopping backup sync thread 4029 ... [ 26.758544] IPVS: stopping backup sync thread 4017 ... [ 26.759770] IPVS: stopping backup sync thread 4039 ... [ 26.760112] IPVS: stopping backup sync thread 4032 ... [ 26.760459] IPVS: stopping backup sync thread 4012 ... [ 26.760838] IPVS: stopping backup sync thread 4028 ... [ 26.761286] IPVS: stopping backup sync thread 4034 ... [ 26.767261] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.770185] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.790590] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.791846] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.794950] IPVS: sync thread started: state = BACKUP, mcast_ifn = lo, syncid = 3, id = 0 [ 26.811302] [ 26.811304] ============================================= [ 26.811305] [ INFO: possible recursive locking detected ] [ 26.811317] 4.9.95-g13cc540 #2 Not tainted [ 26.811318] --------------------------------------------- [ 26.811321] syz-executor0/4061 is trying to acquire lock: [ 26.811342] (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 26.811344] but task is already holding lock: [ 26.811354] (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 26.811355] other info that might help us debug this: [ 26.811357] Possible unsafe locking scenario: [ 26.811357] [ 26.811358] CPU0 [ 26.811360] ---- [ 26.811363] lock(rtnl_mutex); [ 26.811366] lock(rtnl_mutex); [ 26.811368] [ 26.811368] *** DEADLOCK *** [ 26.811368] [ 26.811370] May be due to missing lock nesting notation [ 26.811370] [ 26.811373] 2 locks held by syz-executor0/4061: [ 26.811385] #0: (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 26.811398] #1: (ipvs->sync_mutex){+.+.+.}, at: [] do_ip_vs_set_ctl+0x90d/0xbd0 [ 26.811399] [ 26.811399] stack backtrace: [ 26.811406] CPU: 1 PID: 4061 Comm: syz-executor0 Not tainted 4.9.95-g13cc540 #2 [ 26.811409] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.811422] ffff8801d78c7480 ffffffff81eb0ba9 ffffffff8539d290 ffffffff8539d290 [ 26.811431] ffffffff8539d290 ffff8801b4a888e8 3b9ef1081871f670 ffff8801d78c7640 [ 26.811439] ffffffff814259ef ffffffff84c98ca0 ffffffff84feeb80 ffffffff84c98ca4 [ 26.811441] Call Trace: [ 26.811451] [] dump_stack+0xc1/0x128 [ 26.811464] [] __lock_acquire.cold.59+0x166/0x5f8 [ 26.811475] [] ? debug_check_no_locks_freed+0x210/0x210 [ 26.811482] [] ? __lock_is_held+0xa2/0xf0 [ 26.811489] [] lock_acquire+0x130/0x3e0 [ 26.811496] [] ? rtnl_lock+0x17/0x20 [ 26.811503] [] ? rtnl_lock+0x17/0x20 [ 26.811512] [] mutex_lock_nested+0xc0/0x870 [ 26.811519] [] ? rtnl_lock+0x17/0x20 [ 26.811527] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 26.811535] [] ? qtaguid_untag+0x41a/0x620 [ 26.811542] [] ? mutex_trylock+0x3e0/0x3e0 [ 26.811551] [] ? _raw_spin_unlock_bh+0x30/0x40 [ 26.811557] [] ? qtaguid_untag+0x31e/0x620 [ 26.811564] [] ? __lock_is_held+0xa2/0xf0 [ 26.811571] [] rtnl_lock+0x17/0x20 [ 26.811581] [] ip_mc_drop_socket+0x8c/0x230 [ 26.811588] [] inet_release+0x5b/0x1d0 [ 26.811598] [] sock_release+0x96/0x1c0 [ 26.811607] [] start_sync_thread+0xa0e/0x1ea0 [ 26.811616] [] ? ip_vs_proc_sync_conn+0x952/0x952 [ 26.811624] [] ? ip_vs_sync_conn+0x2a90/0x2a90 [ 26.811631] [] ? mark_held_locks+0xc7/0x130 [ 26.811638] [] ? mutex_lock_nested+0x572/0x870 [ 26.811646] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 26.811653] [] ? mutex_lock_nested+0x596/0x870 [ 26.811660] [] ? do_ip_vs_set_ctl+0x90d/0xbd0 [ 26.811667] [] ? mutex_trylock+0x3e0/0x3e0 [ 26.811675] [] ? memcpy+0x45/0x50 [ 26.811681] [] do_ip_vs_set_ctl+0x91f/0xbd0 [ 26.811688] [] ? ip_vs_genl_set_cmd+0x9c0/0x9c0 [ 26.811695] [] ? mutex_lock_nested+0x572/0x870 [ 26.811703] [] ? __mutex_unlock_slowpath+0x25b/0x3c0 [ 26.811710] [] ? __mutex_unlock_slowpath+0x221/0x3c0 [ 26.811717] [] ? __ww_mutex_lock+0x14c0/0x14c0 [ 26.811727] [] ? sock_has_perm+0x292/0x3e0 [ 26.811734] [] ? sock_has_perm+0x9f/0x3e0 [ 26.811741] [] ? mutex_unlock+0x9/0x10 [ 26.811751] [] nf_setsockopt+0x6d/0xc0 [ 26.811759] [] ip_setsockopt+0x9a/0xb0 [ 26.811768] [] raw_setsockopt+0xb7/0xd0 [ 26.811775] [] sock_common_setsockopt+0x9a/0xe0 [ 26.811783] [] SyS_setsockopt+0x166/0x260 [ 26.811789] [] ? SyS_recv+0x40/0x40 [ 26.811800] [] ? __do_page_fault+0x183/0xd50 [ 26.811807] [] ? move_addr_to_kernel+0x50/0x50 [ 26.811816] [] ? do_syscall_64+0x48/0x490 [ 26.811823] [] ? SyS_recv+0x40/0x40 [ 26.811828] [] do_syscall_64+0x1a6/0x490 [ 26.811835] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb [ 27.590657] IPVS: stopping backup sync thread 4064 ... [ 27.596158] IPVS: stopping backup sync thread 4065 ... [ 27.605010] IPVS: stopping backup sync thread 4066 ... [ 27.607190] IPVS: stopping backup sync thread 4074 ... [ 27.613729] IPVS: stopping backup sync thread 4072 ...