[ 32.748784] audit: type=1800 audit(1580737453.940:33): pid=7115 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed(directio)" comm="startpar" name="rc.local" dev="sda1" ino=2465 res=0 [ 32.776522] audit: type=1800 audit(1580737453.950:34): pid=7115 uid=0 auid=4294967295 ses=4294967295 subj=system_u:system_r:kernel_t:s0 op="collect_data" cause="failed(directio)" comm="startpar" name="rmnologin" dev="sda1" ino=2456 res=0 Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 36.404789] random: sshd: uninitialized urandom read (32 bytes read) [ 36.852891] audit: type=1400 audit(1580737458.050:35): avc: denied { map } for pid=7289 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 [ 36.904591] random: sshd: uninitialized urandom read (32 bytes read) [ 37.601266] random: sshd: uninitialized urandom read (32 bytes read) [ 37.795508] random: sshd: uninitialized urandom read (32 bytes read) Warning: Permanently added '10.128.0.194' (ECDSA) to the list of known hosts. [ 43.342599] random: sshd: uninitialized urandom read (32 bytes read) executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 43.463802] audit: type=1400 audit(1580737464.660:36): avc: denied { map } for pid=7301 comm="syz-executor964" path="/root/syz-executor964641760" dev="sda1" ino=16483 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 48.260840] [ 48.262508] ====================================================== [ 48.268809] WARNING: possible circular locking dependency detected [ 48.275194] 4.14.169-syzkaller #0 Not tainted [ 48.279674] ------------------------------------------------------ [ 48.285992] syz-executor964/8248 is trying to acquire lock: [ 48.291678] (event_mutex){+.+.}, at: [] perf_trace_destroy+0x28/0x100 [ 48.299895] [ 48.299895] but task is already holding lock: [ 48.305993] (&event->child_mutex){+.+.}, at: [] perf_event_release_kernel+0x207/0x880 [ 48.315623] [ 48.315623] which lock already depends on the new lock. [ 48.315623] [ 48.323934] [ 48.323934] the existing dependency chain (in reverse order) is: [ 48.331549] [ 48.331549] -> #5 (&event->child_mutex){+.+.}: [ 48.337702] lock_acquire+0x16f/0x430 [ 48.342027] __mutex_lock+0xe8/0x1470 [ 48.346890] mutex_lock_nested+0x16/0x20 [ 48.351476] perf_event_for_each_child+0x8a/0x150 [ 48.356823] perf_ioctl+0x1d9/0xe50 [ 48.360964] do_vfs_ioctl+0x7ae/0x1060 [ 48.365401] SyS_ioctl+0x8f/0xc0 [ 48.369292] do_syscall_64+0x1e8/0x640 [ 48.373783] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 48.379617] [ 48.379617] -> #4 (&cpuctx_mutex){+.+.}: [ 48.385155] lock_acquire+0x16f/0x430 [ 48.389546] __mutex_lock+0xe8/0x1470 [ 48.393859] mutex_lock_nested+0x16/0x20 [ 48.398433] perf_event_init_cpu+0xc2/0x170 [ 48.403262] perf_event_init+0x2d8/0x31a [ 48.407823] start_kernel+0x3b6/0x67d [ 48.412124] x86_64_start_reservations+0x29/0x2b [ 48.417391] x86_64_start_kernel+0x77/0x7b [ 48.422137] secondary_startup_64+0xa5/0xb0 [ 48.426980] [ 48.426980] -> #3 (pmus_lock){+.+.}: [ 48.432161] lock_acquire+0x16f/0x430 [ 48.436469] __mutex_lock+0xe8/0x1470 [ 48.440769] mutex_lock_nested+0x16/0x20 [ 48.445336] perf_event_init_cpu+0x2f/0x170 [ 48.450157] cpuhp_invoke_callback+0x1ea/0x1ab0 [ 48.455347] _cpu_up+0x228/0x530 [ 48.459317] do_cpu_up+0xa6/0x160 [ 48.463291] cpu_up+0x1b/0x20 [ 48.466920] smp_init+0x157/0x170 [ 48.470881] kernel_init_freeable+0x30b/0x532 [ 48.475899] kernel_init+0x12/0x162 [ 48.480037] ret_from_fork+0x24/0x30 [ 48.484249] [ 48.484249] -> #2 (cpu_hotplug_lock.rw_sem){++++}: [ 48.490646] lock_acquire+0x16f/0x430 [ 48.494968] cpus_read_lock+0x3d/0xc0 [ 48.499294] static_key_slow_inc+0x13/0x30 [ 48.504048] tracepoint_probe_register_prio+0x4d6/0x6d0 [ 48.510438] tracepoint_probe_register+0x2b/0x40 [ 48.515696] trace_event_reg+0x277/0x330 [ 48.520259] perf_trace_init+0x449/0xaa0 [ 48.524825] perf_tp_event_init+0x7d/0xf0 [ 48.529580] perf_try_init_event+0x164/0x200 [ 48.535102] perf_event_alloc.part.0+0xd92/0x25c0 [ 48.540499] SYSC_perf_event_open+0xad1/0x2690 [ 48.545963] SyS_perf_event_open+0x34/0x40 [ 48.550798] do_syscall_64+0x1e8/0x640 [ 48.555362] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 48.561052] [ 48.561052] -> #1 (tracepoints_mutex){+.+.}: [ 48.566936] lock_acquire+0x16f/0x430 [ 48.571327] __mutex_lock+0xe8/0x1470 [ 48.576245] mutex_lock_nested+0x16/0x20 [ 48.580807] tracepoint_probe_register_prio+0x36/0x6d0 [ 48.586586] tracepoint_probe_register+0x2b/0x40 [ 48.591843] trace_event_reg+0x277/0x330 [ 48.596409] perf_trace_init+0x449/0xaa0 [ 48.600973] perf_tp_event_init+0x7d/0xf0 [ 48.605623] perf_try_init_event+0x164/0x200 [ 48.610542] perf_event_alloc.part.0+0xd92/0x25c0 [ 48.615887] SYSC_perf_event_open+0xad1/0x2690 [ 48.621058] SyS_perf_event_open+0x34/0x40 [ 48.625804] do_syscall_64+0x1e8/0x640 [ 48.630206] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 48.635894] [ 48.635894] -> #0 (event_mutex){+.+.}: [ 48.641249] __lock_acquire+0x2cb3/0x4620 [ 48.645900] lock_acquire+0x16f/0x430 [ 48.650210] __mutex_lock+0xe8/0x1470 [ 48.654856] mutex_lock_nested+0x16/0x20 [ 48.659417] perf_trace_destroy+0x28/0x100 [ 48.664162] tp_perf_event_destroy+0x16/0x20 [ 48.669072] _free_event+0x330/0xe70 [ 48.673299] free_event+0x38/0x50 [ 48.677251] perf_event_release_kernel+0x364/0x880 [ 48.682696] perf_release+0x37/0x50 [ 48.686839] __fput+0x275/0x7a0 [ 48.690620] ____fput+0x16/0x20 [ 48.694406] task_work_run+0x114/0x190 [ 48.698797] do_exit+0xa1a/0x2cd0 [ 48.702765] do_group_exit+0x111/0x330 [ 48.707157] get_signal+0x381/0x1cd0 [ 48.711372] do_signal+0x86/0x19a0 [ 48.715426] exit_to_usermode_loop+0x15c/0x220 [ 48.720611] do_syscall_64+0x4bc/0x640 [ 48.725177] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 48.730873] [ 48.730873] other info that might help us debug this: [ 48.730873] [ 48.739169] Chain exists of: [ 48.739169] event_mutex --> &cpuctx_mutex --> &event->child_mutex [ 48.739169] [ 48.749904] Possible unsafe locking scenario: [ 48.749904] [ 48.755953] CPU0 CPU1 [ 48.760605] ---- ---- [ 48.765253] lock(&event->child_mutex); [ 48.769293] lock(&cpuctx_mutex); [ 48.775678] lock(&event->child_mutex); [ 48.782239] lock(event_mutex); [ 48.785593] [ 48.785593] *** DEADLOCK *** [ 48.785593] [ 48.791645] 2 locks held by syz-executor964/8248: [ 48.796821] #0: (&ctx->mutex){+.+.}, at: [] perf_event_release_kernel+0x1fd/0x880 [ 48.806168] #1: (&event->child_mutex){+.+.}, at: [] perf_event_release_kernel+0x207/0x880 [ 48.816569] [ 48.816569] stack backtrace: [ 48.821053] CPU: 0 PID: 8248 Comm: syz-executor964 Not tainted 4.14.169-syzkaller #0 [ 48.828920] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.838263] Call Trace: [ 48.840833] dump_stack+0x142/0x197 [ 48.844453] print_circular_bug.isra.0.cold+0x1cc/0x28f [ 48.849816] __lock_acquire+0x2cb3/0x4620 [ 48.853942] ? find_held_lock+0x35/0x130 [ 48.857985] ? trace_hardirqs_on+0x10/0x10 [ 48.862217] lock_acquire+0x16f/0x430 [ 48.865994] ? perf_trace_destroy+0x28/0x100 [ 48.870396] ? perf_trace_destroy+0x28/0x100 [ 48.874791] __mutex_lock+0xe8/0x1470 [ 48.878570] ? perf_trace_destroy+0x28/0x100 [ 48.882956] ? perf_trace_destroy+0x28/0x100 [ 48.887343] ? task_function_call+0xe7/0x130 [ 48.891745] ? mutex_trylock+0x1c0/0x1c0 [ 48.895785] ? save_trace+0x290/0x290 [ 48.899573] ? __mutex_lock+0x36a/0x1470 [ 48.903620] ? perf_event_release_kernel+0x1f3/0x880 [ 48.908701] ? __lock_is_held+0xb6/0x140 [ 48.912745] ? check_preemption_disabled+0x3c/0x250 [ 48.917742] mutex_lock_nested+0x16/0x20 [ 48.921800] ? mutex_lock_nested+0x16/0x20 [ 48.926022] perf_trace_destroy+0x28/0x100 [ 48.930256] tp_perf_event_destroy+0x16/0x20 [ 48.934649] ? perf_tp_event_init+0xf0/0xf0 [ 48.938963] _free_event+0x330/0xe70 [ 48.942673] free_event+0x38/0x50 [ 48.946106] perf_event_release_kernel+0x364/0x880 [ 48.951014] ? perf_event_release_kernel+0x880/0x880 [ 48.956111] perf_release+0x37/0x50 [ 48.959875] __fput+0x275/0x7a0 [ 48.963159] ____fput+0x16/0x20 [ 48.966453] task_work_run+0x114/0x190 [ 48.970345] do_exit+0xa1a/0x2cd0 [ 48.973804] ? get_signal+0x319/0x1cd0 [ 48.977695] ? mm_update_next_owner+0x5d0/0x5d0 [ 48.982353] do_group_exit+0x111/0x330 [ 48.986254] get_signal+0x381/0x1cd0 [ 48.989963] ? __mutex_unlock_slowpath+0x71/0x800 [ 48.994790] ? wait_for_completion+0x420/0x420 [ 48.999353] ? trace_hardirqs_on_caller+0x400/0x590 [ 49.004367] do_signal+0x86/0x19a0 [ 49.007913] ? perf_ioctl+0x1fc/0xe50 [ 49.011702] ? __fget+0x210/0x370 [ 49.015132] ? SYSC_perf_event_open+0x2690/0x2690 [ 49.019955] ? setup_sigcontext+0x7d0/0x7d0 [ 49.024254] ? SYSC_perf_event_open+0x2690/0x2690 [ 49.029075] ? do_vfs_ioctl+0xef/0x1060 [ 49.033029] ? selinux_file_mprotect+0x5d0/0x5d0 [ 49.037763] ? lock_downgrade+0x740/0x740 [ 49.041890] ? ioctl_preallocate+0x1c0/0x1c0 [ 49.046626] ? SyS_futex+0x215/0x310 [ 49.050317] ? SyS_futex+0x222/0x310 [ 49.054011] ? exit_to_usermode_loop+0x3d/0x220 [ 49.058657] exit_to_usermode_loop+0x15c/0x220 [ 49.063221] do_syscall_64+0x4bc/0x640 [ 49.067086] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 49.071911] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 49.077077] RIP: 0033:0x446969 [ 49.080265] RSP: 002b:00007f2a61e38db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca [ 49.087950] RAX: fffffffffffffe00 RBX: 00000000006dbc38 RCX: 0000000000446969 [ 49.095199] RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006dbc38 [ 49.102449] RBP: 00000000006dbc30 R08: 0000000000000000 R09: 0000000000000000 executing program executing program executing program executing program executing program [ 49.109698] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dbc3c [ 49.117031] R13: 00007ffed2cc5d3f R14: 00007f2a61e399c0 R15: 000000000000002d executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program