[....] Starting enhanced syslogd: rsyslogd[ 13.633359] audit: type=1400 audit(1517187231.942:5): avc: denied { syslog } for pid=3538 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 periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 17.493836] audit: type=1400 audit(1517187235.802:6): avc: denied { map } for pid=3676 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 Warning: Permanently added '10.128.15.204' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 [ 23.812772] audit: type=1400 audit(1517187242.121:7): avc: denied { map } for pid=3690 comm="syzkaller624657" path="/root/syzkaller624657374" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 RTNETLINK answers: Operation not supported RTNETLINK answers: No buffer space available RTNETLINK answers: Operation not supported [ 24.118219] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument executing program [ 24.544161] ipt_CLUSTERIP: ipt_CLUSTERIP is deprecated and it will removed soon, use xt_cluster instead [ 24.557292] [ 24.558956] ====================================================== [ 24.565243] WARNING: possible circular locking dependency detected [ 24.571534] 4.15.0-rc9+ #284 Not tainted [ 24.575561] ------------------------------------------------------ [ 24.581847] syzkaller624657/3690 is trying to acquire lock: [ 24.587527] (rtnl_mutex){+.+.}, at: [<00000000f8787f89>] rtnl_lock+0x17/0x20 [ 24.594783] [ 24.594783] but task is already holding lock: [ 24.600721] (&xt[i].mutex){+.+.}, at: [<000000007da872a6>] xt_find_table_lock+0x40/0x3d0 [ 24.609015] [ 24.609015] which lock already depends on the new lock. [ 24.609015] [ 24.617298] [ 24.617298] the existing dependency chain (in reverse order) is: [ 24.624888] [ 24.624888] -> #2 (&xt[i].mutex){+.+.}: [ 24.630336] __mutex_lock+0x16f/0x1a80 [ 24.634716] mutex_lock_nested+0x16/0x20 [ 24.639267] xt_find_revision+0xc9/0x2b0 [ 24.643820] do_ip6t_get_ctl+0x8e2/0xaf0 [ 24.648373] nf_getsockopt+0x6a/0xc0 [ 24.652575] ipv6_getsockopt+0x1df/0x2e0 [ 24.657127] tcp_getsockopt+0x82/0xd0 [ 24.661418] sock_common_getsockopt+0x95/0xd0 [ 24.666401] SyS_getsockopt+0x178/0x340 [ 24.670867] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 24.676110] [ 24.676110] -> #1 (sk_lock-AF_INET6){+.+.}: [ 24.681884] lock_sock_nested+0xc2/0x110 [ 24.686434] do_ipv6_setsockopt.isra.8+0x3c5/0x39d0 [ 24.691954] ipv6_setsockopt+0xd7/0x150 [ 24.696421] sctp_setsockopt+0x2a0/0x5de0 [ 24.701063] sock_common_setsockopt+0x95/0xd0 [ 24.706050] SyS_setsockopt+0x189/0x360 [ 24.710528] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 24.715769] [ 24.715769] -> #0 (rtnl_mutex){+.+.}: [ 24.721025] lock_acquire+0x1d5/0x580 [ 24.725324] __mutex_lock+0x16f/0x1a80 [ 24.729711] mutex_lock_nested+0x16/0x20 [ 24.734261] rtnl_lock+0x17/0x20 [ 24.738114] unregister_netdevice_notifier+0x91/0x4e0 [ 24.743792] clusterip_tg_destroy+0x389/0x6e0 [ 24.748781] cleanup_entry+0x218/0x350 [ 24.753159] __do_replace+0x7d7/0xa90 [ 24.757446] do_ipt_set_ctl+0x40f/0x5f0 [ 24.761911] nf_setsockopt+0x67/0xc0 [ 24.766117] ip_setsockopt+0xa1/0xb0 [ 24.770331] tcp_setsockopt+0x82/0xd0 [ 24.774622] sock_common_setsockopt+0x95/0xd0 [ 24.779607] SyS_setsockopt+0x189/0x360 [ 24.784070] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 24.789308] [ 24.789308] other info that might help us debug this: [ 24.789308] [ 24.797418] Chain exists of: [ 24.797418] rtnl_mutex --> sk_lock-AF_INET6 --> &xt[i].mutex [ 24.797418] [ 24.807707] Possible unsafe locking scenario: [ 24.807707] [ 24.813733] CPU0 CPU1 [ 24.818366] ---- ---- [ 24.822999] lock(&xt[i].mutex); [ 24.826421] lock(sk_lock-AF_INET6); [ 24.832712] lock(&xt[i].mutex); [ 24.838653] lock(rtnl_mutex); [ 24.841906] [ 24.841906] *** DEADLOCK *** [ 24.841906] [ 24.847937] 2 locks held by syzkaller624657/3690: [ 24.852745] #0: (sk_lock-AF_INET){+.+.}, at: [<00000000562c484a>] ip_setsockopt+0x8c/0xb0 [ 24.861215] #1: (&xt[i].mutex){+.+.}, at: [<000000007da872a6>] xt_find_table_lock+0x40/0x3d0 [ 24.869940] [ 24.869940] stack backtrace: [ 24.874412] CPU: 0 PID: 3690 Comm: syzkaller624657 Not tainted 4.15.0-rc9+ #284 [ 24.881826] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.891150] Call Trace: [ 24.893726] dump_stack+0x194/0x257 [ 24.897328] ? arch_local_irq_restore+0x53/0x53 [ 24.901969] print_circular_bug.isra.37+0x2cd/0x2dc [ 24.906957] ? save_trace+0xe0/0x2b0 [ 24.910642] __lock_acquire+0x30a8/0x3e00 [ 24.914758] ? print_irqtrace_events+0x270/0x270 [ 24.919488] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 24.924649] ? print_irqtrace_events+0x270/0x270 [ 24.929376] ? print_irqtrace_events+0x270/0x270 [ 24.934103] ? __lock_acquire+0x664/0x3e00 [ 24.938306] ? __lock_acquire+0x664/0x3e00 [ 24.942511] ? __is_insn_slot_addr+0x1fc/0x330 [ 24.947064] ? lock_downgrade+0x980/0x980 [ 24.951181] ? lock_release+0xa40/0xa40 [ 24.955127] ? bpf_prog_kallsyms_find+0xbd/0x440 [ 24.959854] ? check_noncircular+0x20/0x20 [ 24.964059] ? trace_raw_output_xdp_redirect_map_err+0x440/0x440 [ 24.970187] ? is_bpf_text_address+0x7b/0x120 [ 24.974652] ? lock_downgrade+0x980/0x980 [ 24.978771] ? __free_insn_slot+0x5c0/0x5c0 [ 24.983075] lock_acquire+0x1d5/0x580 [ 24.986848] ? lock_acquire+0x1d5/0x580 [ 24.990793] ? rtnl_lock+0x17/0x20 [ 24.994304] ? lock_release+0xa40/0xa40 [ 24.998249] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.004103] ? unwind_get_return_address+0x61/0xa0 [ 25.009003] ? rcu_note_context_switch+0x710/0x710 [ 25.013901] ? __might_sleep+0x95/0x190 [ 25.017854] ? rtnl_lock+0x17/0x20 [ 25.021365] __mutex_lock+0x16f/0x1a80 [ 25.025220] ? rtnl_lock+0x17/0x20 [ 25.028730] ? save_trace+0xe0/0x2b0 [ 25.032414] ? rtnl_lock+0x17/0x20 [ 25.035925] ? __lock_acquire+0x36c0/0x3e00 [ 25.040227] ? mutex_lock_io_nested+0x1900/0x1900 [ 25.045040] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 25.050199] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 25.055359] ? __free_insn_slot+0x5c0/0x5c0 [ 25.059654] ? is_bpf_text_address+0xa4/0x120 [ 25.064123] ? rcutorture_record_progress+0x10/0x10 [ 25.069111] ? is_bpf_text_address+0xa4/0x120 [ 25.073577] ? kernel_text_address+0x102/0x140 [ 25.078130] ? __kernel_text_address+0xd/0x40 [ 25.082598] ? unwind_get_return_address+0x61/0xa0 [ 25.087500] ? check_noncircular+0x20/0x20 [ 25.091703] ? check_noncircular+0x20/0x20 [ 25.095907] ? save_stack+0xa3/0xd0 [ 25.099504] ? save_stack+0x43/0xd0 [ 25.103105] ? kasan_kmalloc+0xad/0xe0 [ 25.106962] ? __kmalloc_node+0x47/0x70 [ 25.110904] ? check_noncircular+0x20/0x20 [ 25.115109] ? do_ipt_set_ctl+0x40f/0x5f0 [ 25.119228] mutex_lock_nested+0x16/0x20 [ 25.123271] ? mutex_lock_nested+0x16/0x20 [ 25.127475] rtnl_lock+0x17/0x20 [ 25.130813] unregister_netdevice_notifier+0x91/0x4e0 [ 25.135971] ? clusterip_tg_destroy+0x36a/0x6e0 [ 25.140609] ? lock_downgrade+0x980/0x980 [ 25.144726] ? register_netdevice_notifier+0x860/0x860 [ 25.149973] ? __lock_is_held+0xb6/0x140 [ 25.154005] ? mark_held_locks+0xaf/0x100 [ 25.158123] ? do_raw_spin_trylock+0x190/0x190 [ 25.162675] ? __local_bh_enable_ip+0x121/0x230 [ 25.167313] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 25.172768] ? clusterip_tg_destroy+0x350/0x6e0 [ 25.177411] ? trace_hardirqs_on+0xd/0x10 [ 25.181528] clusterip_tg_destroy+0x389/0x6e0 [ 25.185994] ? free_modinfo_version+0x70/0x70 [ 25.190458] ? clusterip_tg+0xa40/0xa40 [ 25.194403] ? cpumask_next+0x24/0x30 [ 25.198177] ? __lock_is_held+0xb6/0x140 [ 25.202207] ? clusterip_tg+0xa40/0xa40 [ 25.206152] cleanup_entry+0x218/0x350 [ 25.210009] ? cleanup_match+0x220/0x220 [ 25.214045] ? find_next_bit+0x27/0x30 [ 25.217904] __do_replace+0x7d7/0xa90 [ 25.221679] ? compat_table_info+0x470/0x470 [ 25.226057] ? kasan_check_write+0x14/0x20 [ 25.230263] ? _copy_from_user+0x99/0x110 [ 25.234381] do_ipt_set_ctl+0x40f/0x5f0 [ 25.238328] ? translate_compat_table+0x1b90/0x1b90 [ 25.243316] ? mutex_unlock+0xd/0x10 [ 25.247000] ? nf_sockopt_find.constprop.0+0x1a7/0x220 [ 25.252244] nf_setsockopt+0x67/0xc0 [ 25.255928] ip_setsockopt+0xa1/0xb0 [ 25.259614] tcp_setsockopt+0x82/0xd0 [ 25.263386] sock_common_setsockopt+0x95/0xd0 [ 25.267853] SyS_setsockopt+0x189/0x360 [ 25.271797] ? SyS_recv+0x40/0x40 [ 25.275219] ? entry_SYSCALL_64_fastpath+0x5/0xa0 [ 25.280032] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 25.285023] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 25.289765] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 25.294492] RIP: 0033:0x448e9a executing program [ 25.297649] RSP: 002b:00007ffd38e18718 EFLAGS: 00000206 ORIG_RAX: 0000000000000036 [ 25.305327] RAX: ffffffffffffffda RBX: 00000000006d2100 RCX: 0000000000448e9a [ 25.312567] RDX: 0000000000000040 RSI: 0000000000000000 RDI: 0000000000000004 [ 25.319808] RBP: 00000000006d2100 R08: 00000000000002d8 R09: 0000000002486880 [ 25.327050] R10: 00000000006d2528 R11: 0000000000000206 R12: 0000000000000004 [ 25.334290] R13: 00000000006d50a8 R14: 00000000006d5050 R15: 00000000004a826c 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 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 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 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 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 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 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 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 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 executing program executing program