[....] Starting enhanced syslogd: rsyslogd[ 14.669341] audit: type=1400 audit(1522126151.194:4): avc: denied { syslog } for pid=3648 comm="rsyslogd" capability=34 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=capability2 permissive=1 [?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?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 '10.128.0.20' (ECDSA) to the list of known hosts. executing program executing program executing program syzkaller login: [ 27.699265] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.699597] IPVS: stopping backup sync thread 3810 ... [ 27.716884] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.717350] IPVS: stopping backup sync thread 3814 ... [ 27.735827] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 executing program executing program executing program [ 27.736075] IPVS: stopping backup sync thread 3818 ... [ 27.755364] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.755607] IPVS: stopping backup sync thread 3822 ... [ 27.773541] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.773785] IPVS: stopping backup sync thread 3826 ... [ 27.791031] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 executing program executing program executing program [ 27.791289] IPVS: stopping backup sync thread 3830 ... [ 27.809665] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.810576] IPVS: stopping backup sync thread 3834 ... [ 27.833817] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.834058] IPVS: stopping backup sync thread 3838 ... executing program executing program [ 27.852035] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.852281] IPVS: stopping backup sync thread 3842 ... [ 27.871087] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.871324] IPVS: stopping backup sync thread 3846 ... [ 27.889868] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 executing program executing program executing program [ 27.890292] IPVS: stopping backup sync thread 3850 ... [ 27.908701] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.908985] IPVS: stopping backup sync thread 3854 ... [ 27.926658] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.927303] IPVS: stopping backup sync thread 3858 ... executing program executing program executing program [ 27.944132] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.944374] IPVS: stopping backup sync thread 3862 ... [ 27.963622] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.963873] IPVS: stopping backup sync thread 3866 ... [ 27.981153] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 27.987307] IPVS: stopping backup sync thread 3870 ... executing program executing program executing program [ 27.998865] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.007477] IPVS: stopping backup sync thread 3874 ... [ 28.016516] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.016747] IPVS: stopping backup sync thread 3878 ... [ 28.033894] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.034833] IPVS: stopping backup sync thread 3882 ... executing program executing program executing program [ 28.052539] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.052778] IPVS: stopping backup sync thread 3886 ... [ 28.071044] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.071295] IPVS: stopping backup sync thread 3890 ... [ 28.088332] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.088614] IPVS: stopping backup sync thread 3894 ... executing program executing program executing program [ 28.105818] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.106699] IPVS: stopping backup sync thread 3898 ... [ 28.124151] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.124391] IPVS: stopping backup sync thread 3902 ... [ 28.141363] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.143437] IPVS: stopping backup sync thread 3906 ... executing program executing program [ 28.158937] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.167329] IPVS: stopping backup sync thread 3910 ... [ 28.176685] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.185323] IPVS: stopping backup sync thread 3914 ... [ 28.195564] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.195805] IPVS: stopping backup sync thread 3918 ... executing program executing program executing program executing program [ 28.212952] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.213912] IPVS: stopping backup sync thread 3922 ... [ 28.231442] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.231690] IPVS: stopping backup sync thread 3926 ... [ 28.248890] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.257562] IPVS: stopping backup sync thread 3930 ... executing program executing program executing program [ 28.266842] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.267375] IPVS: stopping backup sync thread 3934 ... [ 28.284235] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.284480] IPVS: stopping backup sync thread 3938 ... [ 28.301642] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.307341] IPVS: stopping backup sync thread 3942 ... executing program executing program executing program [ 28.319498] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.319739] IPVS: stopping backup sync thread 3946 ... [ 28.336910] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.337174] IPVS: stopping backup sync thread 3950 ... [ 28.354301] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.355271] IPVS: stopping backup sync thread 3954 ... executing program executing program executing program [ 28.371842] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.377319] IPVS: stopping backup sync thread 3958 ... [ 28.389610] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.389855] IPVS: stopping backup sync thread 3962 ... [ 28.408338] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.409862] IPVS: stopping backup sync thread 3966 ... executing program executing program executing program [ 28.426468] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.427316] IPVS: stopping backup sync thread 3970 ... [ 28.444169] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.447276] IPVS: stopping backup sync thread 3974 ... [ 28.461993] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.462229] IPVS: stopping backup sync thread 3978 ... executing program executing program executing program [ 28.479527] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.479763] IPVS: stopping backup sync thread 3982 ... [ 28.496934] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.505819] IPVS: stopping backup sync thread 3986 ... [ 28.514898] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.515139] IPVS: stopping backup sync thread 3990 ... executing program executing program executing program [ 28.533361] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.533621] IPVS: stopping backup sync thread 3994 ... [ 28.550849] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.551081] IPVS: stopping backup sync thread 3998 ... [ 28.568662] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.568944] IPVS: stopping backup sync thread 4002 ... executing program executing program executing program [ 28.586706] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.595537] IPVS: stopping backup sync thread 4006 ... [ 28.604521] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.605486] IPVS: stopping backup sync thread 4010 ... [ 28.621882] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.627369] IPVS: stopping backup sync thread 4014 ... executing program [ 28.639661] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.640606] IPVS: stopping backup sync thread 4018 ... [ 28.657272] IPVS: sync thread started: state = BACKUP, mcast_ifn = sit0, syncid = 0, id = 0 [ 28.666108] IPVS: stopping backup sync thread 4022 ... [ 28.671720] [ 28.673330] ============================================= [ 28.678834] [ INFO: possible recursive locking detected ] [ 28.684343] 4.9.90-gdd1e37e #66 Not tainted [ 28.688633] --------------------------------------------- [ 28.694137] syzkaller063908/4021 is trying to acquire lock: [ 28.699817] (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 28.707593] but task is already holding lock: [ 28.712230] (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 28.719997] other info that might help us debug this: [ 28.725327] Possible unsafe locking scenario: [ 28.725327] [ 28.731353] CPU0 [ 28.733903] ---- [ 28.736453] lock(rtnl_mutex); [ 28.739960] lock(rtnl_mutex); [ 28.743438] [ 28.743438] *** DEADLOCK *** [ 28.743438] [ 28.749468] May be due to missing lock nesting notation [ 28.749468] [ 28.756376] 2 locks held by syzkaller063908/4021: [ 28.761184] #0: (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 [ 28.769530] #1: (ipvs->sync_mutex){+.+.+.}, at: [] do_ip_vs_set_ctl+0x8e7/0xc00 [ 28.779161] [ 28.779161] stack backtrace: [ 28.783628] CPU: 1 PID: 4021 Comm: syzkaller063908 Not tainted 4.9.90-gdd1e37e #66 [ 28.791303] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 28.800681] ffff8801d7597460 ffffffff81d94ee9 ffffffff8536fd80 ffffffff8536fd80 [ 28.808673] dffffc0000000000 8ae5654dd039751d 0000000000000000 ffff8801d7597630 [ 28.816657] ffffffff8123b925 ffffffff84c6bca0 ffffffff84fbeb18 ffffffff84c6bca4 [ 28.824630] Call Trace: [ 28.827191] [] dump_stack+0xc1/0x128 [ 28.832527] [] __lock_acquire+0xe35/0x3640 [ 28.838393] [] ? debug_check_no_locks_freed+0x2c0/0x2c0 [ 28.845383] [] ? __lock_is_held+0xa1/0xf0 [ 28.851155] [] lock_acquire+0x12e/0x410 [ 28.856756] [] ? rtnl_lock+0x17/0x20 [ 28.862093] [] ? rtnl_lock+0x17/0x20 [ 28.867447] [] mutex_lock_nested+0xbb/0x870 [ 28.873387] [] ? rtnl_lock+0x17/0x20 [ 28.878722] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.885533] [] ? qtaguid_untag+0x487/0x680 [ 28.891389] [] ? mutex_lock_killable_nested+0x960/0x960 [ 28.898817] [] ? _raw_spin_unlock_bh+0x30/0x40 [ 28.905024] [] ? qtaguid_untag+0x326/0x680 [ 28.910879] [] rtnl_lock+0x17/0x20 [ 28.916043] [] ip_mc_drop_socket+0x88/0x230 [ 28.921985] [] inet_release+0x5b/0x1d0 [ 28.927504] [] sock_release+0x8d/0x1e0 [ 28.933012] [] start_sync_thread+0x191b/0x1ef0 [ 28.939219] [] ? ip_vs_proc_sync_conn+0xc90/0xc90 [ 28.945683] [] ? ip_vs_sync_conn+0x2b30/0x2b30 [ 28.951890] [] ? mark_held_locks+0xaf/0x100 [ 28.957847] [] ? mutex_lock_nested+0x5e3/0x870 [ 28.964072] [] ? trace_hardirqs_on_caller+0x38b/0x590 [ 28.970907] [] ? mutex_lock_nested+0x56f/0x870 [ 28.977124] [] ? do_ip_vs_set_ctl+0x8e7/0xc00 [ 28.983271] [] ? mutex_lock_killable_nested+0x960/0x960 [ 28.990292] [] ? memcpy+0x45/0x50 [ 28.995375] [] do_ip_vs_set_ctl+0x8fb/0xc00 [ 29.001326] [] ? ip_vs_genl_dump_services+0x430/0x430 [ 29.008136] [] ? mutex_lock_nested+0x5e3/0x870 [ 29.014338] [] ? __mutex_unlock_slowpath+0x25a/0x3d0 [ 29.021059] [] ? __mutex_unlock_slowpath+0x220/0x3d0 [ 29.027782] [] ? __ww_mutex_lock_interruptible+0x14a0/0x14a0 [ 29.035211] [] ? sock_has_perm+0x292/0x3e0 [ 29.041064] [] ? sock_has_perm+0x9f/0x3e0 [ 29.046832] [] ? mutex_unlock+0x9/0x10 [ 29.052339] [] nf_setsockopt+0x67/0xc0 [ 29.057848] [] ip_setsockopt+0x97/0xa0 [ 29.063356] [] udp_setsockopt+0x45/0x80 [ 29.068952] [] sock_common_setsockopt+0x95/0xd0 [ 29.075241] [] SyS_setsockopt+0x160/0x250 [ 29.081009] [] ? SyS_recv+0x40/0x40 [ 29.086257] [] ? key_get_type_from_user.constprop.10+0xe0/0xe0 [ 29.093864] [] ? move_addr_to_kernel+0x50/0x50 [ 29.100066] [] ? do_syscall_64+0x48/0x490 [ 29.105836] [] ? SyS_recv+0x40/0x40 [ 29.111083] [] do_syscall_64+0x1a4/0x490 [ 29.116764] [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb