INIT: Entering runlevel: 2 [info] Using makefile-style concurrent boot in runlevel 2. [....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?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 'ci-upstream-mmots-kasan-gce-8,10.128.0.13' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 net.ipv6.conf.syz5.accept_dad = 0 net.ipv6.conf.syz4.accept_dad = 0 net.ipv6.conf.syz5.router_solicitations = 0 net.ipv6.conf.syz4.router_solicitations = 0 executing program net.ipv6.conf.syz7.accept_dad = 0 net.ipv6.conf.syz7.router_solicitations = 0 net.ipv6.conf.syz3.accept_dad = 0 net.ipv6.conf.syz6.accept_dad = 0 executing program net.ipv6.conf.syz3.router_solicitations = 0 net.ipv6.conf.syz6.router_solicitations = 0 executing program net.ipv6.conf.syz1.accept_dad = 0 net.ipv6.conf.syz2.accept_dad = 0 net.ipv6.conf.syz1.router_solicitations = 0 net.ipv6.conf.syz2.router_solicitations = 0 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 42.365733] [ 42.367374] ====================================================== [ 42.373657] WARNING: possible circular locking dependency detected [ 42.379940] 4.13.0-mm1+ #7 Not tainted [ 42.383788] ------------------------------------------------------ [ 42.390071] syzkaller529737/11903 is trying to acquire lock: [ 42.395829] (event_mutex){+.+.}, at: [] perf_trace_destroy+0x28/0x100 [ 42.404040] [ 42.404040] but task is already holding lock: [ 42.409978] (&mm->mmap_sem){++++}, at: [] vm_mmap_pgoff+0x198/0x280 [ 42.418011] [ 42.418011] which lock already depends on the new lock. [ 42.418011] [ 42.426299] [ 42.426299] the existing dependency chain (in reverse order) is: [ 42.433882] [ 42.433882] -> #7 (&mm->mmap_sem){++++}: [ 42.439393] __lock_acquire+0x328f/0x4620 [ 42.444027] lock_acquire+0x1d5/0x580 [ 42.448315] __might_fault+0x13a/0x1d0 [ 42.452691] _copy_to_user+0x2c/0xc0 [ 42.456896] filldir+0x1a7/0x320 [ 42.460749] dcache_readdir+0x12d/0x5e0 [ 42.465208] iterate_dir+0x4b2/0x5d0 [ 42.469407] SyS_getdents+0x225/0x450 [ 42.473694] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.478932] [ 42.478932] -> #6 (&sb->s_type->i_mutex_key#5){++++}: [ 42.485572] down_write+0x87/0x120 [ 42.489604] handle_create+0x30c/0x760 [ 42.493975] devtmpfsd+0x3eb/0x520 [ 42.497998] kthread+0x39c/0x470 [ 42.501853] ret_from_fork+0x2a/0x40 [ 42.506056] [ 42.506056] -> #5 ((complete)&req.done){+.+.}: [ 42.512085] __lock_acquire+0x328f/0x4620 [ 42.516719] lock_acquire+0x1d5/0x580 [ 42.521007] wait_for_completion+0xc8/0x770 [ 42.525819] devtmpfs_create_node+0x32b/0x4a0 [ 42.530799] device_add+0x120f/0x1640 [ 42.535085] device_create_groups_vargs+0x1f3/0x250 [ 42.540584] device_create+0xda/0x110 [ 42.544869] msr_device_create+0x26/0x40 [ 42.549415] cpuhp_invoke_callback+0x256/0x14d0 [ 42.554570] cpuhp_thread_fun+0x265/0x520 [ 42.559203] smpboot_thread_fn+0x489/0x850 [ 42.563927] kthread+0x39c/0x470 [ 42.567785] ret_from_fork+0x2a/0x40 [ 42.571982] [ 42.571982] -> #4 (cpuhp_state){+.+.}: [ 42.577317] __lock_acquire+0x328f/0x4620 [ 42.581949] lock_acquire+0x1d5/0x580 [ 42.586234] cpuhp_issue_call+0x1a2/0x3e0 [ 42.590864] __cpuhp_setup_state_cpuslocked+0x2d6/0x5f0 [ 42.596710] __cpuhp_setup_state+0xb0/0x140 [ 42.601519] page_writeback_init+0x4d/0x71 [ 42.606236] pagecache_init+0x48/0x4f [ 42.610523] start_kernel+0x6c1/0x754 [ 42.614808] x86_64_start_reservations+0x2a/0x2c [ 42.620046] x86_64_start_kernel+0x77/0x7a [ 42.624765] verify_cpu+0x0/0xfb [ 42.628622] [ 42.628622] -> #3 (cpuhp_state_mutex){+.+.}: [ 42.634476] __lock_acquire+0x328f/0x4620 [ 42.639120] lock_acquire+0x1d5/0x580 [ 42.643407] __mutex_lock+0x16f/0x1870 [ 42.647777] mutex_lock_nested+0x16/0x20 [ 42.652321] __cpuhp_setup_state_cpuslocked+0x5b/0x5f0 [ 42.658082] __cpuhp_setup_state+0xb0/0x140 [ 42.662888] kvm_guest_init+0x1f3/0x20f [ 42.667347] setup_arch+0x1879/0x1a93 [ 42.671635] start_kernel+0xa5/0x754 [ 42.675837] x86_64_start_reservations+0x2a/0x2c [ 42.681077] x86_64_start_kernel+0x77/0x7a [ 42.685796] verify_cpu+0x0/0xfb [ 42.689643] [ 42.689643] -> #2 (cpu_hotplug_lock.rw_sem){++++}: [ 42.696024] __lock_acquire+0x328f/0x4620 [ 42.700665] lock_acquire+0x1d5/0x580 [ 42.704950] cpus_read_lock+0x42/0x90 [ 42.709237] static_key_slow_inc+0x9d/0x3c0 [ 42.714044] tracepoint_probe_register_prio+0x80d/0x9a0 [ 42.719890] tracepoint_probe_register+0x2a/0x40 [ 42.725131] trace_event_reg+0x167/0x320 [ 42.729677] perf_trace_init+0x4f9/0xab0 [ 42.734221] perf_tp_event_init+0x7d/0xf0 [ 42.738851] perf_try_init_event+0xc9/0x1f0 [ 42.743655] perf_event_alloc+0x1c5b/0x2a00 [ 42.748462] SYSC_perf_event_open+0x84e/0x2e00 [ 42.753871] SyS_perf_event_open+0x39/0x50 [ 42.758595] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.763832] [ 42.763832] -> #1 (tracepoints_mutex){+.+.}: [ 42.769685] __lock_acquire+0x328f/0x4620 [ 42.774319] lock_acquire+0x1d5/0x580 [ 42.778613] __mutex_lock+0x16f/0x1870 [ 42.782983] mutex_lock_nested+0x16/0x20 [ 42.787535] tracepoint_probe_register_prio+0xa0/0x9a0 [ 42.793293] tracepoint_probe_register+0x2a/0x40 [ 42.798534] trace_event_reg+0x167/0x320 [ 42.803078] perf_trace_init+0x4f9/0xab0 [ 42.807625] perf_tp_event_init+0x7d/0xf0 [ 42.812255] perf_try_init_event+0xc9/0x1f0 [ 42.817061] perf_event_alloc+0x1c5b/0x2a00 [ 42.821865] SYSC_perf_event_open+0x84e/0x2e00 [ 42.826931] SyS_perf_event_open+0x39/0x50 [ 42.831651] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.836889] [ 42.836889] -> #0 (event_mutex){+.+.}: [ 42.842225] check_prev_add+0x865/0x1520 [ 42.846768] __lock_acquire+0x328f/0x4620 [ 42.851399] lock_acquire+0x1d5/0x580 [ 42.855686] __mutex_lock+0x16f/0x1870 [ 42.860057] mutex_lock_nested+0x16/0x20 [ 42.864602] perf_trace_destroy+0x28/0x100 [ 42.869319] tp_perf_event_destroy+0x15/0x20 [ 42.874212] _free_event+0x401/0x1130 [ 42.878494] put_event+0x24/0x30 [ 42.882345] perf_mmap_close+0x60d/0xf90 [ 42.886892] remove_vma+0xb4/0x1b0 [ 42.890915] do_munmap+0x82a/0xdf0 [ 42.894939] mmap_region+0x59e/0x15a0 [ 42.899225] do_mmap+0x6a1/0xd50 [ 42.903163] vm_mmap_pgoff+0x1de/0x280 [ 42.907532] SyS_mmap_pgoff+0x23b/0x5f0 [ 42.911990] SyS_mmap+0x16/0x20 [ 42.915755] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.920993] [ 42.920993] other info that might help us debug this: [ 42.920993] [ 42.929100] Chain exists of: [ 42.929100] event_mutex --> &sb->s_type->i_mutex_key#5 --> &mm->mmap_sem [ 42.929100] [ 42.940423] Possible unsafe locking scenario: [ 42.940423] [ 42.946445] CPU0 CPU1 [ 42.951073] ---- ---- [ 42.955700] lock(&mm->mmap_sem); [ 42.959203] lock(&sb->s_type->i_mutex_key#5); [ 42.966351] lock(&mm->mmap_sem); [ 42.972372] lock(event_mutex); [ 42.975700] [ 42.975700] *** DEADLOCK *** [ 42.975700] [ 42.981722] 1 lock held by syzkaller529737/11903: [ 42.986524] #0: (&mm->mmap_sem){++++}, at: [] vm_mmap_pgoff+0x198/0x280 [ 42.994989] [ 42.994989] stack backtrace: [ 42.999453] CPU: 1 PID: 11903 Comm: syzkaller529737 Not tainted 4.13.0-mm1+ #7 [ 43.006773] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 43.016094] Call Trace: [ 43.018654] dump_stack+0x194/0x257 [ 43.022249] ? arch_local_irq_restore+0x53/0x53 [ 43.026886] print_circular_bug+0x503/0x710 [ 43.031174] ? print_circular_bug_entry+0xb0/0xb0 [ 43.035983] ? unwind_dump+0x4c0/0x4c0 [ 43.039838] check_prev_add+0x865/0x1520 [ 43.043863] ? copy_trace+0x1d0/0x1d0 [ 43.047638] ? check_usage+0xb70/0xb70 [ 43.051492] ? hlock_class+0x140/0x140 [ 43.055344] ? copy_trace+0x1d0/0x1d0 [ 43.059108] __lock_acquire+0x328f/0x4620 [ 43.063226] ? __lock_acquire+0x328f/0x4620 [ 43.067520] ? copy_trace+0x1d0/0x1d0 [ 43.071288] ? debug_check_no_locks_freed+0x3d0/0x3d0 [ 43.076441] ? __unwind_start+0x169/0x330 [ 43.080555] ? unwind_get_return_address+0x61/0xa0 [ 43.085452] ? __read_once_size_nocheck.constprop.8+0x10/0x10 [ 43.091299] ? do_munmap+0x82a/0xdf0 [ 43.094976] ? __read_once_size_nocheck.constprop.8+0x10/0x10 [ 43.100833] ? mmap_region+0x59e/0x15a0 [ 43.104770] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 43.109749] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 43.114729] ? unwind_dump+0x4c0/0x4c0 [ 43.118580] ? unwind_dump+0x4c0/0x4c0 [ 43.122438] ? unwind_next_frame.part.6+0x1ae/0xc70 [ 43.127417] ? unwind_dump+0x4c0/0x4c0 [ 43.131272] ? __unwind_start+0x169/0x330 [ 43.135384] ? unwind_get_return_address+0x61/0xa0 [ 43.140278] ? __save_stack_trace+0x61/0xd0 [ 43.144576] ? check_noncircular+0x20/0x20 [ 43.148778] ? do_munmap+0x82a/0xdf0 [ 43.152459] ? save_stack_trace+0x16/0x20 [ 43.156572] ? __lock_acquire+0x20fd/0x4620 [ 43.160858] ? save_stack_trace+0x16/0x20 [ 43.164972] ? __lock_acquire+0x20fd/0x4620 [ 43.169262] lock_acquire+0x1d5/0x580 [ 43.173031] ? perf_trace_destroy+0x28/0x100 [ 43.177404] ? lock_release+0xd70/0xd70 [ 43.181341] ? check_same_owner+0x320/0x320 [ 43.185627] ? __might_sleep+0x95/0x190 [ 43.189569] ? perf_trace_destroy+0x28/0x100 [ 43.193947] __mutex_lock+0x16f/0x1870 [ 43.197800] ? perf_trace_destroy+0x28/0x100 [ 43.202178] ? lock_acquire+0x1d5/0x580 [ 43.206116] ? perf_mmap_close+0x33f/0xf90 [ 43.210312] ? perf_trace_destroy+0x28/0x100 [ 43.214689] ? mutex_lock_io_nested+0x1740/0x1740 [ 43.219500] ? lock_acquire+0x1d5/0x580 [ 43.223445] ? perf_mmap_close+0x5cb/0xf90 [ 43.227644] ? check_same_owner+0x320/0x320 [ 43.231930] ? check_noncircular+0x20/0x20 [ 43.236129] ? __mutex_lock+0x16f/0x1870 [ 43.240153] ? perf_mmap_close+0x33f/0xf90 [ 43.244355] ? check_noncircular+0x20/0x20 [ 43.248554] ? check_noncircular+0x20/0x20 [ 43.252753] ? __might_sleep+0x95/0x190 [ 43.256695] ? print_usage_bug+0x480/0x480 [ 43.260893] ? __mutex_lock+0x16f/0x1870 [ 43.264917] ? perf_mmap_close+0x5cb/0xf90 [ 43.269115] ? print_usage_bug+0x480/0x480 [ 43.273317] ? find_held_lock+0x39/0x1d0 [ 43.277343] ? check_noncircular+0x20/0x20 [ 43.281555] ? perf_addr_filters_splice+0x18f/0x810 [ 43.286546] ? lock_downgrade+0x990/0x990 [ 43.290660] ? free_filters_list+0x2f0/0x2f0 [ 43.295034] ? __wake_up+0x1e/0x50 [ 43.298539] ? __lock_is_held+0xbc/0x140 [ 43.302566] mutex_lock_nested+0x16/0x20 [ 43.306590] ? mutex_lock_nested+0x16/0x20 [ 43.310791] perf_trace_destroy+0x28/0x100 [ 43.314987] ? perf_tp_event_init+0xf0/0xf0 [ 43.319277] tp_perf_event_destroy+0x15/0x20 [ 43.323653] _free_event+0x401/0x1130 [ 43.327424] ? ring_buffer_attach+0x830/0x830 [ 43.331883] ? wait_for_completion+0x770/0x770 [ 43.336431] ? ring_buffer_put+0x140/0x140 [ 43.340633] ? lock_release+0xd70/0xd70 [ 43.344575] ? atomic_dec_and_mutex_lock+0x112/0x150 [ 43.349642] ? atomic_dec_and_mutex_lock+0x112/0x150 [ 43.354708] put_event+0x24/0x30 [ 43.358039] perf_mmap_close+0x60d/0xf90 [ 43.362067] ? perf_compat_ioctl+0x70/0x70