[....] Starting enhanced syslogd: rsyslogd[ 15.530245] audit: type=1400 audit(1519182273.176:5): avc: denied { syslog } for pid=4008 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 syzkaller login: [ 19.318980] audit: type=1400 audit(1519182276.964:6): avc: denied { map } for pid=4148 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 '10.128.0.21' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 [ 25.638764] audit: type=1400 audit(1519182283.284:7): avc: denied { map } for pid=4162 comm="syzkaller400094" path="/root/syzkaller400094856" 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 [ 25.648582] IPVS: ftp: loaded support on port[0] = 21 RTNETLINK answers: Operation not supported RTNETLINK answers: No buffer space available RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported [ 25.865392] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument executing program [ 26.178236] [ 26.179889] ===================================== [ 26.184699] WARNING: bad unlock balance detected! [ 26.189507] 4.16.0-rc2+ #235 Not tainted [ 26.193532] ------------------------------------- [ 26.198341] syzkaller400094/4163 is trying to release lock (rcu_read_lock_bh) at: [ 26.205940] [] hashlimit_mt_common.isra.10+0x1beb/0x2610 [ 26.212919] but there are no more locks to release! [ 26.217901] [ 26.217901] other info that might help us debug this: [ 26.224532] 5 locks held by syzkaller400094/4163: [ 26.229339] #0: (&xt[i].mutex){+.+.}, at: [<0000000069504285>] xt_find_table_lock+0x273/0x3e0 [ 26.238152] #1: (&mm->mmap_sem){++++}, at: [<0000000087c834ca>] __do_page_fault+0x32d/0xc90 [ 26.246792] #2: ((&idev->mc_ifc_timer)){+.-.}, at: [<00000000a0e93f73>] call_timer_fn+0x1c6/0x820 [ 26.255952] #3: (rcu_read_lock){....}, at: [<000000006bbb268b>] mld_sendpack+0x180/0xe70 [ 26.264333] #4: (rcu_read_lock){....}, at: [<0000000092212f5b>] nf_hook.constprop.37+0x0/0x830 [ 26.273230] [ 26.273230] stack backtrace: [ 26.277702] CPU: 0 PID: 4163 Comm: syzkaller400094 Not tainted 4.16.0-rc2+ #235 [ 26.285117] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.294439] Call Trace: [ 26.296991] [ 26.299118] dump_stack+0x194/0x257 [ 26.302713] ? arch_local_irq_restore+0x53/0x53 [ 26.307353] ? hashlimit_mt_common.isra.10+0x1beb/0x2610 [ 26.312773] print_unlock_imbalance_bug+0x12f/0x140 [ 26.317760] lock_release+0x6fe/0xa40 [ 26.321530] ? hashlimit_mt_common.isra.10+0x1beb/0x2610 [ 26.326947] ? lock_downgrade+0x980/0x980 [ 26.331066] ? lock_release+0xa40/0xa40 [ 26.335012] ? __raw_spin_lock_init+0x1c/0x100 [ 26.339569] ? do_raw_spin_trylock+0x190/0x190 [ 26.344127] hashlimit_mt_common.isra.10+0x1c08/0x2610 [ 26.349377] ? lock_downgrade+0x980/0x980 [ 26.353498] ? dsthash_find+0x5b0/0x5b0 [ 26.357441] ? __lock_acquire+0x664/0x3e00 [ 26.361645] ? is_bpf_text_address+0x7b/0x120 [ 26.366109] ? lock_downgrade+0x95a/0x980 [ 26.370228] ? rcutorture_record_progress+0x10/0x10 [ 26.375218] ? __kernel_text_address+0xd/0x40 [ 26.379683] ? unwind_get_return_address+0x61/0xa0 [ 26.384580] hashlimit_mt+0x78/0x90 [ 26.388175] ? hashlimit_mt+0x78/0x90 [ 26.391946] ip6t_do_table+0x98d/0x1a30 [ 26.395894] ? kmem_cache_alloc_trace+0x136/0x740 [ 26.400711] ? mld_sendpack+0x617/0xe70 [ 26.404662] ? ip6t_error+0x60/0x60 [ 26.408257] ? ipv6_setsockopt+0x10b/0x130 [ 26.412463] ? check_noncircular+0x20/0x20 [ 26.416666] ? lock_acquire+0x1d5/0x580 [ 26.420606] ? lock_acquire+0x1d5/0x580 [ 26.424553] ? igmp6_mcf_seq_next+0x660/0x660 [ 26.429023] ? lock_release+0xa40/0xa40 [ 26.432971] ip6table_raw_hook+0x65/0x80 [ 26.437001] nf_hook_slow+0xba/0x1a0 [ 26.440689] nf_hook.constprop.37+0x3f6/0x830 [ 26.445154] ? igmp6_mcf_seq_next+0x660/0x660 [ 26.449619] ? trace_hardirqs_on+0xd/0x10 [ 26.453734] ? __local_bh_enable_ip+0x121/0x230 [ 26.458371] ? _raw_spin_unlock_bh+0x30/0x40 [ 26.462747] ? rt6_uncached_list_add+0x1b7/0x240 [ 26.467469] ? rt6_fill_node+0x18b0/0x18b0 [ 26.471675] ? icmp6_dst_alloc+0x475/0x660 [ 26.475879] ? ip6_mc_leave_src+0x1d0/0x1d0 [ 26.480170] ? icmpv6_flow_init+0x1f6/0x270 [ 26.484463] mld_sendpack+0x6c2/0xe70 [ 26.488237] ? nf_hook.constprop.37+0x830/0x830 [ 26.492876] ? mark_held_locks+0xaf/0x100 [ 26.496995] ? trace_hardirqs_on+0xd/0x10 [ 26.501118] ? __local_bh_enable_ip+0x121/0x230 [ 26.505762] mld_ifc_timer_expire+0x3d9/0x770 [ 26.510234] call_timer_fn+0x228/0x820 [ 26.514091] ? mld_dad_timer_expire+0x100/0x100 [ 26.518728] ? process_timeout+0x40/0x40 [ 26.522758] ? __run_timers+0x7e3/0xb70 [ 26.526700] ? lock_downgrade+0x980/0x980 [ 26.530818] ? debug_object_deactivate+0x364/0x560 [ 26.535715] ? lock_release+0xa40/0xa40 [ 26.539657] ? mark_held_locks+0xaf/0x100 [ 26.543774] ? trace_hardirqs_on_caller+0x19e/0x5c0 [ 26.548759] ? mld_dad_timer_expire+0x100/0x100 [ 26.553397] ? mld_dad_timer_expire+0x100/0x100 [ 26.558041] __run_timers+0x7ee/0xb70 [ 26.561814] ? trigger_dyntick_cpu.isra.29+0x150/0x150 [ 26.567066] ? timerqueue_add+0x1e9/0x280 [ 26.571190] ? check_noncircular+0x20/0x20 [ 26.575394] ? enqueue_hrtimer+0x177/0x4b0 [ 26.579595] ? lock_release+0xa40/0xa40 [ 26.583536] ? retrigger_next_event+0x1e0/0x1e0 [ 26.588176] ? print_irqtrace_events+0x270/0x270 [ 26.592898] ? check_noncircular+0x20/0x20 [ 26.597104] ? clockevents_program_event+0x163/0x2e0 [ 26.602176] ? lock_downgrade+0x980/0x980 [ 26.606293] ? __lock_is_held+0xb6/0x140 [ 26.610326] run_timer_softirq+0x4c/0x70 [ 26.614355] __do_softirq+0x2d7/0xb85 [ 26.618126] ? ktime_get+0x26f/0x3a0 [ 26.621810] ? __irqentry_text_end+0x1f8ad4/0x1f8ad4 [ 26.626883] ? check_noncircular+0x20/0x20 [ 26.631089] ? native_apic_msr_write+0x5c/0x80 [ 26.635637] ? lapic_next_event+0x54/0x80 [ 26.639754] ? clockevents_program_event+0x108/0x2e0 [ 26.644827] ? tick_program_event+0x83/0x100 [ 26.649205] ? __lock_is_held+0xb6/0x140 [ 26.653241] irq_exit+0x1cc/0x200 [ 26.656665] smp_apic_timer_interrupt+0x16b/0x700 [ 26.661474] ? smp_reschedule_interrupt+0xe6/0x650 [ 26.666373] ? smp_call_function_single_interrupt+0x640/0x640 [ 26.672227] ? _raw_spin_lock+0x32/0x40 [ 26.676173] ? _raw_spin_unlock+0x22/0x30 [ 26.680290] ? handle_edge_irq+0x2b4/0x7c0 [ 26.684493] ? task_prio+0x50/0x50 [ 26.688006] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 26.692823] apic_timer_interrupt+0x8e/0xa0 [ 26.697109] [ 26.699315] RIP: 0010:lock_is_held_type+0x18b/0x210 [ 26.704296] RSP: 0018:ffff8801aa126fa0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff12 [ 26.711971] RAX: dffffc0000000000 RBX: 0000000000000282 RCX: ffffffff819dd382 [ 26.719208] RDX: 1ffffffff0d592d5 RSI: ffffffff86b42700 RDI: 0000000000000282 [ 26.726450] RBP: ffff8801aa126fc0 R08: 000000000002fc50 R09: 0000000000000000 [ 26.733689] R10: ffffffffffffffe8 R11: 0000000000000000 R12: ffff8801b7ab2180 [ 26.740926] R13: 0000000000000000 R14: 0000000000001205 R15: 00000000000000f3 [ 26.748170] ? clear_huge_page+0x92/0x730 [ 26.752291] ? trace_event_raw_event_sched_switch+0x810/0x810 [ 26.758147] ___might_sleep+0x35e/0x470 [ 26.762091] ? trace_event_raw_event_sched_switch+0x810/0x810 [ 26.767941] ? __might_sleep+0x95/0x190 [ 26.771887] clear_huge_page+0xa5/0x730 [ 26.775829] ? __raw_spin_lock_init+0x2d/0x100 [ 26.780394] do_huge_pmd_anonymous_page+0x599/0x1b00 [ 26.785475] ? __thp_get_unmapped_area+0x130/0x130 [ 26.790379] ? __lock_acquire+0x664/0x3e00 [ 26.794588] ? __lock_acquire+0x664/0x3e00 [ 26.798791] ? kernel_text_address+0x102/0x140 [ 26.803345] ? __is_insn_slot_addr+0x1fc/0x330 [ 26.807895] ? lock_downgrade+0x980/0x980 [ 26.812016] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 26.817173] ? modules_open+0xa0/0xa0 [ 26.820944] ? trace_raw_output_xdp_redirect_map_err+0x440/0x440 [ 26.827056] ? is_bpf_text_address+0x7b/0x120 [ 26.831518] ? lock_downgrade+0x980/0x980 [ 26.835633] ? lock_release+0xa40/0xa40 [ 26.839574] ? __free_insn_slot+0x5c0/0x5c0 [ 26.843865] ? rcutorture_record_progress+0x10/0x10 [ 26.848855] ? is_bpf_text_address+0xa4/0x120 [ 26.853343] ? kernel_text_address+0x102/0x140 [ 26.857898] __handle_mm_fault+0x1a0c/0x3ce0 [ 26.862278] ? __pmd_alloc+0x4e0/0x4e0 [ 26.866134] ? check_noncircular+0x20/0x20 [ 26.870336] ? print_lockdep_cache.isra.32+0x109/0x109 [ 26.875579] ? find_held_lock+0x35/0x1d0 [ 26.879608] ? handle_mm_fault+0x270/0x970 [ 26.883810] ? lock_downgrade+0x980/0x980 [ 26.887931] handle_mm_fault+0x35c/0x970 [ 26.891961] ? __handle_mm_fault+0x3ce0/0x3ce0 [ 26.896509] ? vmacache_find+0x5f/0x280 [ 26.900830] ? find_vma+0x30/0x150 [ 26.904340] __do_page_fault+0x5c9/0xc90 [ 26.908369] ? mm_fault_error+0x2c0/0x2c0 [ 26.912482] ? kfree+0xd9/0x260 [ 26.915732] ? xt_free_table_info+0x110/0x170 [ 26.920196] ? __do_replace+0x810/0xa70 [ 26.924139] ? check_noncircular+0x20/0x20 [ 26.928340] ? rawv6_setsockopt+0x4a/0xf0 [ 26.932455] ? sock_common_setsockopt+0x95/0xd0 [ 26.937090] do_page_fault+0xee/0x730 [ 26.940859] ? __do_page_fault+0xc90/0xc90 [ 26.945063] ? find_held_lock+0x35/0x1d0 [ 26.949096] ? __might_fault+0x110/0x1d0 [ 26.953126] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 26.957939] page_fault+0x62/0x90 [ 26.961364] RIP: 0010:copy_user_generic_unrolled+0x89/0xc0 [ 26.966954] RSP: 0018:ffff8801aa1279b8 EFLAGS: 00010206 [ 26.972287] RAX: fffff520002ffa06 RBX: 0000000000000030 RCX: 0000000000000006 [ 26.979527] RDX: 0000000000000000 RSI: ffffc900017fd000 RDI: 0000000020849fd0 [ 26.986765] RBP: ffff8801aa1279e8 R08: 0000000000000000 R09: fffff520002ffa06 [ 26.994005] R10: 0000000000000006 R11: fffff520002ffa05 R12: 0000000020849fd0 [ 27.001246] R13: ffffc900017fd000 R14: 00007ffffffff000 R15: 000000002084a000 [ 27.008490] ? _copy_to_user+0x9b/0xc0 [ 27.012347] __do_replace+0x840/0xa70 [ 27.016116] ? compat_table_info+0x4a0/0x4a0 [ 27.020491] ? kasan_check_write+0x14/0x20 [ 27.024692] ? _copy_from_user+0x99/0x110 [ 27.028808] do_ip6t_set_ctl+0x40f/0x5f0 [ 27.032837] ? translate_compat_table+0x1c50/0x1c50 [ 27.037825] ? mutex_unlock+0xd/0x10 [ 27.041508] ? nf_sockopt_find.constprop.0+0x1a7/0x220 [ 27.046752] nf_setsockopt+0x67/0xc0 [ 27.050433] ipv6_setsockopt+0x10b/0x130 [ 27.054463] rawv6_setsockopt+0x4a/0xf0 [ 27.058403] sock_common_setsockopt+0x95/0xd0 [ 27.062872] SyS_setsockopt+0x189/0x360 [ 27.066817] ? SyS_recv+0x40/0x40 [ 27.070239] ? mm_fault_error+0x2c0/0x2c0 [ 27.074354] ? move_addr_to_kernel+0x60/0x60 [ 27.078730] ? do_syscall_64+0xb6/0x940 [ 27.082672] ? SyS_recv+0x40/0x40 [ 27.086093] do_syscall_64+0x280/0x940 [ 27.089948] ? __do_page_fault+0xc90/0xc90 [ 27.094152] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 27.098875] ? syscall_return_slowpath+0x550/0x550 [ 27.103773] ? syscall_return_slowpath+0x2ac/0x550 [ 27.108672] ? prepare_exit_to_usermode+0x350/0x350 [ 27.113656] ? retint_user+0x18/0x18 [ 27.117336] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.122150] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 27.127310] RIP: 0033:0x4464b9 [ 27.130470] RSP: 00