[?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. [ 15.827161] audit: type=1400 audit(1516688101.484:6): avc: denied { map } for pid=3648 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 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.4' (ECDSA) to the list of known hosts. executing program executing program syzkaller login: [ 26.154568] audit: type=1400 audit(1516688111.812:7): avc: denied { map } for pid=3663 comm="syzkaller527375" path="/root/syzkaller527375752" 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 [ 26.199786] [ 26.201457] ====================================================== [ 26.207760] WARNING: possible circular locking dependency detected [ 26.214054] 4.15.0-rc8+ #1 Not tainted [ 26.217923] ------------------------------------------------------ [ 26.224215] syzkaller527375/3669 is trying to acquire lock: [ 26.229900] (event_mutex){+.+.}, at: [<00000000f305855f>] perf_trace_destroy+0x28/0x100 [ 26.238211] [ 26.238211] but task is already holding lock: [ 26.244158] (&event->child_mutex){+.+.}, at: [<000000004142c631>] perf_event_release_kernel+0x2ea/0xc10 [ 26.253864] [ 26.253864] which lock already depends on the new lock. [ 26.253864] [ 26.262151] [ 26.262151] the existing dependency chain (in reverse order) is: [ 26.269742] [ 26.269742] -> #5 (&event->child_mutex){+.+.}: [ 26.275875] __mutex_lock+0x16f/0x1a80 [ 26.280267] mutex_lock_nested+0x16/0x20 [ 26.284879] perf_event_for_each_child+0x8a/0x150 [ 26.290228] perf_ioctl+0x46b/0x1430 [ 26.294467] do_vfs_ioctl+0x1b1/0x1520 [ 26.298865] SyS_ioctl+0x8f/0xc0 [ 26.302745] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 26.308014] [ 26.308014] -> #4 (&cpuctx_mutex){+.+.}: [ 26.313560] __mutex_lock+0x16f/0x1a80 [ 26.317954] mutex_lock_nested+0x16/0x20 [ 26.322532] perf_event_init_cpu+0xb6/0x160 [ 26.327360] perf_event_init+0x4e9/0x549 [ 26.331921] start_kernel+0x4cc/0x819 [ 26.336237] x86_64_start_reservations+0x2a/0x2c [ 26.341495] x86_64_start_kernel+0x77/0x7a [ 26.346238] secondary_startup_64+0xa5/0xb0 [ 26.351073] [ 26.351073] -> #3 (pmus_lock){+.+.}: [ 26.356262] __mutex_lock+0x16f/0x1a80 [ 26.360673] mutex_lock_nested+0x16/0x20 [ 26.365268] perf_event_init_cpu+0x2f/0x160 [ 26.370109] cpuhp_invoke_callback+0x2ea/0x1d20 [ 26.375293] _cpu_up+0x216/0x510 [ 26.379170] do_cpu_up+0x73/0xa0 [ 26.383064] cpu_up+0x18/0x20 [ 26.386680] smp_init+0x13a/0x152 [ 26.390638] kernel_init_freeable+0x2fe/0x521 [ 26.395641] kernel_init+0x13/0x180 [ 26.399786] ret_from_fork+0x3a/0x50 [ 26.403995] [ 26.403995] -> #2 (cpu_hotplug_lock.rw_sem){++++}: [ 26.410420] cpus_read_lock+0x42/0x90 [ 26.414731] static_key_slow_inc+0x9d/0x3c0 [ 26.419559] tracepoint_probe_register_prio+0x80d/0x9a0 [ 26.425515] tracepoint_probe_register+0x2a/0x40 [ 26.430867] trace_event_reg+0x167/0x320 [ 26.435436] perf_trace_init+0x4ef/0xab0 [ 26.440015] perf_tp_event_init+0x7d/0xf0 [ 26.444664] perf_try_init_event+0xc9/0x1f0 [ 26.449486] perf_event_alloc+0x1cc6/0x2b00 [ 26.454302] SYSC_perf_event_open+0x84e/0x2e00 [ 26.459383] SyS_perf_event_open+0x39/0x50 [ 26.464133] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 26.469386] [ 26.469386] -> #1 (tracepoints_mutex){+.+.}: [ 26.475263] __mutex_lock+0x16f/0x1a80 [ 26.479737] mutex_lock_nested+0x16/0x20 [ 26.484293] tracepoint_probe_register_prio+0xa0/0x9a0 [ 26.490080] tracepoint_probe_register+0x2a/0x40 [ 26.495330] trace_event_reg+0x167/0x320 [ 26.499885] perf_trace_init+0x4ef/0xab0 [ 26.504452] perf_tp_event_init+0x7d/0xf0 [ 26.509101] perf_try_init_event+0xc9/0x1f0 [ 26.513944] perf_event_alloc+0x1cc6/0x2b00 [ 26.518980] SYSC_perf_event_open+0x84e/0x2e00 [ 26.524068] SyS_perf_event_open+0x39/0x50 [ 26.528806] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 26.534054] [ 26.534054] -> #0 (event_mutex){+.+.}: [ 26.539403] lock_acquire+0x1d5/0x580 [ 26.543712] __mutex_lock+0x16f/0x1a80 [ 26.548251] mutex_lock_nested+0x16/0x20 [ 26.552825] perf_trace_destroy+0x28/0x100 [ 26.557586] tp_perf_event_destroy+0x15/0x20 [ 26.562512] _free_event+0x3bd/0x10f0 [ 26.566831] free_event+0x84/0x150 [ 26.570886] perf_event_release_kernel+0x54e/0xc10 [ 26.576337] perf_release+0x37/0x50 [ 26.580497] __fput+0x327/0x7e0 [ 26.584295] ____fput+0x15/0x20 [ 26.588098] task_work_run+0x199/0x270 [ 26.592536] do_exit+0x9bb/0x1ad0 [ 26.596513] do_group_exit+0x149/0x400 [ 26.600924] get_signal+0x73f/0x16c0 [ 26.605165] do_signal+0x90/0x1eb0 [ 26.609226] exit_to_usermode_loop+0x214/0x310 [ 26.614324] do_syscall_64+0x6dc/0x920 [ 26.618727] return_from_SYSCALL_64+0x0/0x75 [ 26.623637] [ 26.623637] other info that might help us debug this: [ 26.623637] [ 26.631752] Chain exists of: [ 26.631752] event_mutex --> &cpuctx_mutex --> &event->child_mutex [ 26.631752] [ 26.642569] Possible unsafe locking scenario: [ 26.642569] [ 26.648605] CPU0 CPU1 [ 26.653506] ---- ---- [ 26.658143] lock(&event->child_mutex); [ 26.662181] lock(&cpuctx_mutex); [ 26.668216] lock(&event->child_mutex); [ 26.674767] lock(event_mutex); [ 26.678120] [ 26.678120] *** DEADLOCK *** [ 26.678120] [ 26.684160] 2 locks held by syzkaller527375/3669: [ 26.688976] #0: (&ctx->mutex){+.+.}, at: [<00000000b54e8121>] perf_event_release_kernel+0x2dc/0xc10 [ 26.698327] #1: (&event->child_mutex){+.+.}, at: [<000000004142c631>] perf_event_release_kernel+0x2ea/0xc10 [ 26.708461] [ 26.708461] stack backtrace: [ 26.712938] CPU: 1 PID: 3669 Comm: syzkaller527375 Not tainted 4.15.0-rc8+ #1 [ 26.720186] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.729537] Call Trace: [ 26.732114] dump_stack+0x194/0x257 [ 26.735745] ? arch_local_irq_restore+0x53/0x53 [ 26.740415] print_circular_bug.isra.37+0x2cd/0x2dc [ 26.745443] ? save_trace+0xe0/0x2b0 [ 26.749151] __lock_acquire+0x30a8/0x3e00 [ 26.753302] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 26.758492] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 26.763672] ? __lock_acquire+0x664/0x3e00 [ 26.767904] ? __lock_acquire+0x2d15/0x3e00 [ 26.772210] ? print_irqtrace_events+0x270/0x270 [ 26.776962] ? check_noncircular+0x20/0x20 [ 26.781182] ? __lock_acquire+0x664/0x3e00 [ 26.785398] ? check_noncircular+0x20/0x20 [ 26.789623] ? check_noncircular+0x20/0x20 [ 26.793846] ? lock_acquire+0x1d5/0x580 [ 26.797805] ? lock_acquire+0x1d5/0x580 [ 26.801789] ? perf_event_detach_bpf_prog+0x92/0x3d0 [ 26.806875] lock_acquire+0x1d5/0x580 [ 26.810662] ? lock_acquire+0x1d5/0x580 [ 26.814620] ? perf_trace_destroy+0x28/0x100 [ 26.819009] ? lock_release+0xa40/0xa40 [ 26.822956] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 26.828833] ? check_noncircular+0x20/0x20 [ 26.833046] ? rcu_note_context_switch+0x710/0x710 [ 26.837953] ? __might_sleep+0x95/0x190 [ 26.841910] ? perf_trace_destroy+0x28/0x100 [ 26.846306] __mutex_lock+0x16f/0x1a80 [ 26.850176] ? perf_trace_destroy+0x28/0x100 [ 26.854575] ? perf_trace_destroy+0x28/0x100 [ 26.858978] ? find_held_lock+0x35/0x1d0 [ 26.863035] ? mutex_lock_io_nested+0x1900/0x1900 [ 26.867857] ? perf_event_detach_bpf_prog+0x275/0x3d0 [ 26.873029] ? lock_downgrade+0x980/0x980 [ 26.877171] ? __perf_remove_from_context+0x19d/0x3e0 [ 26.882362] ? mark_held_locks+0xaf/0x100 [ 26.886510] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 26.891341] ? trace_hardirqs_on+0xd/0x10 [ 26.895488] ? generic_exec_single+0x18a/0x5b0 [ 26.900062] ? wait_for_completion+0x770/0x770 [ 26.904636] ? perf_event_release_kernel+0x2ea/0xc10 [ 26.909728] ? __mutex_lock+0x16f/0x1a80 [ 26.913772] ? perf_event_release_kernel+0x2ea/0xc10 [ 26.918974] ? check_noncircular+0x20/0x20 [ 26.923196] ? perf_event_release_kernel+0x2ea/0xc10 [ 26.928463] ? perf_addr_filters_splice+0x18f/0x810 [ 26.933471] ? mutex_lock_io_nested+0x1900/0x1900 [ 26.938314] ? free_filters_list+0x2f0/0x2f0 [ 26.942708] ? mutex_unlock+0xd/0x10 [ 26.946413] ? __lock_is_held+0xb6/0x140 [ 26.950471] mutex_lock_nested+0x16/0x20 [ 26.954542] ? mutex_lock_nested+0x16/0x20 [ 26.958774] perf_trace_destroy+0x28/0x100 [ 26.963002] ? perf_tp_event_init+0xf0/0xf0 [ 26.967303] tp_perf_event_destroy+0x15/0x20 [ 26.971691] _free_event+0x3bd/0x10f0 [ 26.975475] ? ring_buffer_attach+0x830/0x830 [ 26.979959] ? event_function_call+0x2f5/0x5a0 [ 26.984529] ? list_del_event+0xb30/0xb30 [ 26.988663] ? task_function_call+0x220/0x220 [ 26.993150] ? lock_downgrade+0x980/0x980 [ 26.997277] ? lock_release+0xa40/0xa40 [ 27.001250] ? list_del_event+0xb30/0xb30 [ 27.005387] free_event+0x84/0x150 [ 27.008938] ? _free_event+0x10f0/0x10f0 [ 27.013010] perf_event_release_kernel+0x54e/0xc10 [ 27.018107] ? put_event+0x30/0x30 [ 27.021649] ? mntput_no_expire+0x130/0xa90 [ 27.025965] ? lock_downgrade+0x980/0x980 [ 27.030093] ? kmem_cache_free+0x267/0x2a0 [ 27.034314] ? lock_release+0xa40/0xa40 [ 27.038280] ? __dentry_kill+0x487/0x6d0 [ 27.042338] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 27.048214] ? locks_remove_file+0x3fa/0x5a0 [ 27.052625] ? fcntl_setlk+0x10c0/0x10c0 [ 27.056673] ? fsnotify+0x7b3/0x1140 [ 27.060374] ? fsnotify_first_mark+0x2b0/0x2b0 [ 27.064953] ? perf_event_release_kernel+0xc10/0xc10 [ 27.070031] perf_release+0x37/0x50 [ 27.073644] __fput+0x327/0x7e0 [ 27.076903] ? fput+0x140/0x140 [ 27.080160] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 27.086027] ? _raw_spin_unlock_irq+0x27/0x70 [ 27.090508] ____fput+0x15/0x20 [ 27.093816] task_work_run+0x199/0x270 [ 27.097680] ? task_work_cancel+0x210/0x210 [ 27.101979] ? _raw_spin_unlock+0x22/0x30 [ 27.106112] ? switch_task_namespaces+0x87/0xc0 [ 27.110764] do_exit+0x9bb/0x1ad0 [ 27.114214] ? find_held_lock+0x35/0x1d0 [ 27.118266] ? mm_update_next_owner+0x930/0x930 [ 27.122911] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 27.128084] ? lock_downgrade+0x980/0x980 [ 27.132223] ? __unqueue_futex+0x1c0/0x290 [ 27.136440] ? lock_release+0xa40/0xa40 [ 27.140398] ? fault_in_user_writeable+0x90/0x90 [ 27.145148] ? do_raw_spin_trylock+0x190/0x190 [ 27.149721] ? futex_wake+0x680/0x680 [ 27.153595] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 27.158676] ? futex_wait+0x6a9/0x9a0 [ 27.162454] ? check_noncircular+0x20/0x20 [ 27.166666] ? wake_up_q+0x8a/0xe0 [ 27.170182] ? drop_futex_key_refs.isra.12+0x63/0xb0 [ 27.175268] ? futex_wake+0x2ca/0x680 [ 27.179062] ? find_held_lock+0x35/0x1d0 [ 27.183121] ? get_signal+0x7ae/0x16c0 [ 27.187007] ? lock_downgrade+0x980/0x980 [ 27.191138] do_group_exit+0x149/0x400 [ 27.195017] ? do_raw_spin_trylock+0x190/0x190 [ 27.199587] ? SyS_exit+0x30/0x30 [ 27.203018] ? _raw_spin_unlock_irq+0x27/0x70 [ 27.207494] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 27.212504] get_signal+0x73f/0x16c0 [ 27.216227] ? ptrace_notify+0x130/0x130 [ 27.220280] ? lock_downgrade+0x980/0x980 [ 27.224440] ? lock_release+0xa40/0xa40 [ 27.228400] ? list_add_event+0x1370/0x1370 [ 27.232710] ? mark_held_locks+0xaf/0x100 [ 27.236842] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 27.241928] do_signal+0x90/0x1eb0 [ 27.245445] ? SYSC_perf_event_open+0x4c3/0x2e00 [ 27.250187] ? find_held_lock+0x35/0x1d0 [ 27.254250] ? perf_trace_sys_exit+0x1d3/0x700 [ 27.258822] ? setup_sigcontext+0x7d0/0x7d0 [ 27.263135] ? lockdep_sys_exit_thunk+0x35/0x35 [ 27.267799] ? rcu_read_lock_sched_held+0x108/0x120 [ 27.272818] ? syscall_trace_enter+0x5fb/0x1100 [ 27.277465] ? rcu_pm_notify+0xc0/0xc0 [ 27.281334] ? exit_to_usermode_loop+0x8c/0x310 [ 27.285992] exit_to_usermode_loop+0x214/0x310 [ 27.290568] ? trace_event_raw_event_sys_exit+0x260/0x260 [ 27.296089] ? do_syscall_64+0xb6/0x920 [ 27.300043] do_syscall_64+0x6dc/0x920 [ 27.303911] ? __do_page_fault+0xc90/0xc90 [ 27.308138] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 27.313139] ? syscall_return_slowpath+0x550/0x550 [ 27.318061] ? syscall_return_slowpath+0x2ad/0x550 [ 27.322993] ? prepare_exit_to_usermode+0x340/0x340 [ 27.328063] ? return_from_SYSCALL_64+0x10/0x75 [ 27.332728] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.337559] entry_SYSCALL64_slow_path+0x25/0x25 [ 27.342296] RIP: 0033:0x445df9 [ 27.345464] RSP: 002b:00007f07b34c9db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca executing program executing program executing program executing program executing program [ 27.353173] RAX: fffffffffffffe00 RBX: 00000000006dbc3c RCX: 0000000000445df9 [ 27.360429] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000006dbc3c [ 27.367696] RBP: 00000000006dbc38 R08: 0000000000000000 R09: 0000000000000000 [ 27.374947] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 27.382199] R13: 00007fffd43fdbef R14: 00007f07b34ca9c0 R15: 0000000000000005 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 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 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 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 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