[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.107' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 67.422158][ C1] [ 67.424497][ C1] ======================================================== [ 67.431666][ C1] WARNING: possible irq lock inversion dependency detected [ 67.438878][ C1] 5.9.0-rc5-next-20200918-syzkaller #0 Not tainted [ 67.445350][ C1] -------------------------------------------------------- [ 67.452534][ C1] swapper/1/0 just changed the state of lock: [ 67.458572][ C1] ffff8882153f6108 (&group->lock){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 67.468471][ C1] but this lock took another, SOFTIRQ-READ-unsafe lock in the past: [ 67.476428][ C1] (&card->ctl_files_rwlock){.+.+}-{2:2} [ 67.476442][ C1] [ 67.476442][ C1] [ 67.476442][ C1] and interrupts could create inverse lock ordering between them. [ 67.476442][ C1] [ 67.496334][ C1] [ 67.496334][ C1] other info that might help us debug this: [ 67.504371][ C1] Possible interrupt unsafe locking scenario: [ 67.504371][ C1] [ 67.512681][ C1] CPU0 CPU1 [ 67.518030][ C1] ---- ---- [ 67.523372][ C1] lock(&card->ctl_files_rwlock); [ 67.528470][ C1] local_irq_disable(); [ 67.535209][ C1] lock(&group->lock); [ 67.541864][ C1] lock(&card->ctl_files_rwlock); [ 67.549495][ C1] [ 67.552922][ C1] lock(&group->lock); [ 67.557237][ C1] [ 67.557237][ C1] *** DEADLOCK *** [ 67.557237][ C1] [ 67.565366][ C1] 1 lock held by swapper/1/0: [ 67.570037][ C1] #0: ffffc90000da8d80 ((&dpcm->timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 [ 67.579318][ C1] [ 67.579318][ C1] the shortest dependencies between 2nd lock and 1st lock: [ 67.588690][ C1] -> (&card->ctl_files_rwlock){.+.+}-{2:2} { [ 67.594743][ C1] HARDIRQ-ON-R at: [ 67.598801][ C1] lock_acquire+0x1f2/0xaa0 [ 67.605110][ C1] _raw_read_lock+0x5b/0x70 [ 67.611411][ C1] snd_ctl_notify.part.0+0x36/0x550 [ 67.618414][ C1] snd_ctl_notify+0x8f/0xb0 [ 67.624719][ C1] __snd_ctl_add_replace+0x638/0x800 [ 67.631801][ C1] snd_ctl_add_replace+0x76/0x130 [ 67.638637][ C1] snd_dummy_probe+0xc22/0x1180 [ 67.645302][ C1] platform_drv_probe+0x87/0x140 [ 67.652042][ C1] really_probe+0x282/0x9f0 [ 67.658346][ C1] driver_probe_device+0xfe/0x1d0 [ 67.665175][ C1] __device_attach_driver+0x1c2/0x220 [ 67.672367][ C1] bus_for_each_drv+0x15f/0x1e0 [ 67.679032][ C1] __device_attach+0x228/0x470 [ 67.685607][ C1] bus_probe_device+0x1e4/0x290 [ 67.692275][ C1] device_add+0xb17/0x1c40 [ 67.698504][ C1] platform_device_add+0x34f/0x6d0 [ 67.705418][ C1] platform_device_register_full+0x38c/0x4e0 [ 67.713207][ C1] alsa_card_dummy_init+0x1e0/0x309 [ 67.720225][ C1] do_one_initcall+0x103/0x6f0 [ 67.726794][ C1] kernel_init_freeable+0x652/0x6d6 [ 67.733795][ C1] kernel_init+0xd/0x1b8 [ 67.739874][ C1] ret_from_fork+0x1f/0x30 [ 67.746095][ C1] SOFTIRQ-ON-R at: [ 67.750187][ C1] lock_acquire+0x1f2/0xaa0 [ 67.756502][ C1] _raw_read_lock+0x5b/0x70 [ 67.762809][ C1] snd_ctl_notify.part.0+0x36/0x550 [ 67.769809][ C1] snd_ctl_notify+0x8f/0xb0 [ 67.776115][ C1] __snd_ctl_add_replace+0x638/0x800 [ 67.783206][ C1] snd_ctl_add_replace+0x76/0x130 [ 67.790054][ C1] snd_dummy_probe+0xc22/0x1180 [ 67.796705][ C1] platform_drv_probe+0x87/0x140 [ 67.803440][ C1] really_probe+0x282/0x9f0 [ 67.809758][ C1] driver_probe_device+0xfe/0x1d0 [ 67.816595][ C1] __device_attach_driver+0x1c2/0x220 [ 67.823785][ C1] bus_for_each_drv+0x15f/0x1e0 [ 67.830451][ C1] __device_attach+0x228/0x470 [ 67.837037][ C1] bus_probe_device+0x1e4/0x290 [ 67.843690][ C1] device_add+0xb17/0x1c40 [ 67.849917][ C1] platform_device_add+0x34f/0x6d0 [ 67.857101][ C1] platform_device_register_full+0x38c/0x4e0 [ 67.864901][ C1] alsa_card_dummy_init+0x1e0/0x309 [ 67.871908][ C1] do_one_initcall+0x103/0x6f0 [ 67.878478][ C1] kernel_init_freeable+0x652/0x6d6 [ 67.885491][ C1] kernel_init+0xd/0x1b8 [ 67.891546][ C1] ret_from_fork+0x1f/0x30 [ 67.897752][ C1] (null) at: [ 67.901286][ C1] ================================================================================ [ 67.910550][ C1] UBSAN: array-index-out-of-bounds in kernel/locking/lockdep.c:2240:40 [ 67.918774][ C1] index 9 is out of range for type 'lock_trace *[9]' [ 67.925423][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0-rc5-next-20200918-syzkaller #0 [ 67.934522][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 67.944572][ C1] Call Trace: [ 67.947830][ C1] [ 67.950659][ C1] dump_stack+0x198/0x1fb [ 67.954972][ C1] ubsan_epilogue+0xb/0x5a [ 67.959370][ C1] __ubsan_handle_out_of_bounds.cold+0x62/0x6c [ 67.965501][ C1] ? vprintk_func+0x95/0x1e0 [ 67.970067][ C1] print_shortest_lock_dependencies.cold+0x11c/0x2e2 [ 67.976715][ C1] print_irq_inversion_bug.part.0+0x2c6/0x2ee [ 67.982759][ C1] mark_lock.cold+0x57/0x74 [ 67.987252][ C1] ? lock_chain_count+0x20/0x20 [ 67.992100][ C1] ? lock_is_held_type+0xbb/0xf0 [ 67.997014][ C1] ? find_held_lock+0x2d/0x110 [ 68.001785][ C1] ? debug_object_activate+0x287/0x3e0 [ 68.007233][ C1] ? lock_downgrade+0x830/0x830 [ 68.012060][ C1] __lock_acquire+0x118a/0x56d0 [ 68.018394][ C1] ? lock_downgrade+0x830/0x830 [ 68.023235][ C1] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 68.029213][ C1] ? mark_lock+0xf7/0x2420 [ 68.033624][ C1] lock_acquire+0x1f2/0xaa0 [ 68.038105][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 68.043992][ C1] ? lock_release+0x890/0x890 [ 68.048655][ C1] ? find_held_lock+0x2d/0x110 [ 68.053409][ C1] ? loopback_jiffies_timer_function+0x188/0x220 [ 68.059785][ C1] ? _raw_spin_lock_irqsave+0xa9/0xd0 [ 68.065179][ C1] _raw_spin_lock_irqsave+0x94/0xd0 [ 68.073932][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 68.079849][ C1] _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 68.085606][ C1] snd_pcm_period_elapsed+0x24/0x250 [ 68.090884][ C1] loopback_jiffies_timer_function+0x1a8/0x220 [ 68.097042][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 68.103540][ C1] call_timer_fn+0x1a5/0x6b0 [ 68.108109][ C1] ? add_timer_on+0x4a0/0x4a0 [ 68.112795][ C1] ? lock_downgrade+0x830/0x830 [ 68.117633][ C1] ? rwlock_bug.part.0+0x90/0x90 [ 68.122547][ C1] ? _raw_spin_unlock_irq+0x1f/0x80 [ 68.127725][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 68.134226][ C1] __run_timers.part.0+0x67c/0xa50 [ 68.139327][ C1] ? call_timer_fn+0x6b0/0x6b0 [ 68.144068][ C1] ? lapic_next_event+0x4d/0x80 [ 68.148905][ C1] ? kvm_sched_clock_read+0x14/0x40 [ 68.154083][ C1] ? sched_clock+0x2a/0x40 [ 68.158487][ C1] ? sched_clock_cpu+0x18/0x1f0 [ 68.163320][ C1] ? hrtimer_interrupt+0x6f4/0x940 [ 68.168410][ C1] run_timer_softirq+0xb3/0x1d0 [ 68.173242][ C1] __do_softirq+0x203/0xab6 [ 68.177742][ C1] asm_call_on_stack+0xf/0x20 [ 68.182406][ C1] [ 68.185328][ C1] do_softirq_own_stack+0x9d/0xd0 [ 68.191050][ C1] irq_exit_rcu+0x235/0x280 [ 68.195732][ C1] sysvec_apic_timer_interrupt+0x51/0xf0 [ 68.201369][ C1] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 68.207355][ C1] RIP: 0010:native_safe_halt+0xe/0x10 [ 68.212738][ C1] Code: 89 ef e8 a5 99 76 f9 e9 86 fe ff ff 48 89 df e8 98 99 76 f9 e9 7b ff ff ff cc cc cc e9 07 00 00 00 0f 00 2d c4 14 49 00 fb f4 90 e9 07 00 00 00 0f 00 2d b4 14 49 00 f4 c3 cc cc 55 53 e8 09 [ 68.232375][ C1] RSP: 0018:ffffc90000d3fd80 EFLAGS: 00000293 [ 68.238433][ C1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff171e639 [ 68.246399][ C1] RDX: ffff8880a961a340 RSI: ffffffff883fd4d3 RDI: 0000000000000000 [ 68.254438][ C1] RBP: ffff88821a913064 R08: 0000000000000001 R09: 0000000000000001 [ 68.262405][ C1] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 [ 68.271066][ C1] R13: ffff88821a913000 R14: ffff88821a913064 R15: ffff8882185fc004 [ 68.279027][ C1] ? acpi_idle_do_entry+0x1e3/0x330 [ 68.284751][ C1] acpi_idle_do_entry+0x1e8/0x330 [ 68.291076][ C1] acpi_idle_enter+0x35a/0x550 [ 68.296448][ C1] cpuidle_enter_state+0x1ab/0xd20 [ 68.301594][ C1] ? tick_nohz_idle_stop_tick+0x50b/0xbd0 [ 68.307303][ C1] cpuidle_enter+0x4a/0xa0 [ 68.311697][ C1] do_idle+0x48e/0x730 [ 68.315758][ C1] ? arch_cpu_idle_exit+0x70/0x70 [ 68.320761][ C1] ? _raw_write_unlock_irqrestore+0x11/0x90 [ 68.326656][ C1] ? lockdep_hardirqs_on+0x53/0x100 [ 68.331857][ C1] cpu_startup_entry+0x14/0x20 [ 68.336601][ C1] secondary_startup_64_no_verify+0xa6/0xab [ 68.342486][ C1] ================================================================================ [ 68.351755][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 68.362146][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0-rc5-next-20200918-syzkaller #0 [ 68.371662][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 68.384032][ C1] Call Trace: [ 68.387682][ C1] [ 68.390531][ C1] dump_stack+0x198/0x1fb [ 68.394846][ C1] panic+0x382/0x7fb [ 68.399679][ C1] ? __warn_printk+0xf3/0xf3 [ 68.404267][ C1] ? secondary_startup_64_no_verify+0xa6/0xab [ 68.410334][ C1] ? ubsan_epilogue+0x3e/0x5a [ 68.416317][ C1] ? ubsan_epilogue+0x35/0x5a [ 68.421231][ C1] ubsan_epilogue+0x54/0x5a [ 68.425733][ C1] __ubsan_handle_out_of_bounds.cold+0x62/0x6c [ 68.431866][ C1] ? vprintk_func+0x95/0x1e0 [ 68.436435][ C1] print_shortest_lock_dependencies.cold+0x11c/0x2e2 [ 68.443109][ C1] print_irq_inversion_bug.part.0+0x2c6/0x2ee [ 68.449163][ C1] mark_lock.cold+0x57/0x74 [ 68.453647][ C1] ? lock_chain_count+0x20/0x20 [ 68.460409][ C1] ? lock_is_held_type+0xbb/0xf0 [ 68.465960][ C1] ? find_held_lock+0x2d/0x110 [ 68.470717][ C1] ? debug_object_activate+0x287/0x3e0 [ 68.476167][ C1] ? lock_downgrade+0x830/0x830 [ 68.481011][ C1] __lock_acquire+0x118a/0x56d0 [ 68.485861][ C1] ? lock_downgrade+0x830/0x830 [ 68.491981][ C1] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 68.497953][ C1] ? mark_lock+0xf7/0x2420 [ 68.502358][ C1] lock_acquire+0x1f2/0xaa0 [ 68.507316][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 68.513289][ C1] ? lock_release+0x890/0x890 [ 68.518028][ C1] ? find_held_lock+0x2d/0x110 [ 68.522775][ C1] ? loopback_jiffies_timer_function+0x188/0x220 [ 68.529088][ C1] ? _raw_spin_lock_irqsave+0xa9/0xd0 [ 68.534474][ C1] _raw_spin_lock_irqsave+0x94/0xd0 [ 68.539654][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 68.545532][ C1] _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 68.551233][ C1] snd_pcm_period_elapsed+0x24/0x250 [ 68.556518][ C1] loopback_jiffies_timer_function+0x1a8/0x220 [ 68.563280][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 68.569959][ C1] call_timer_fn+0x1a5/0x6b0 [ 68.574533][ C1] ? add_timer_on+0x4a0/0x4a0 [ 68.579190][ C1] ? lock_downgrade+0x830/0x830 [ 68.584300][ C1] ? rwlock_bug.part.0+0x90/0x90 [ 68.590804][ C1] ? _raw_spin_unlock_irq+0x1f/0x80 [ 68.595988][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 68.602492][ C1] __run_timers.part.0+0x67c/0xa50 [ 68.607872][ C1] ? call_timer_fn+0x6b0/0x6b0 [ 68.612619][ C1] ? lapic_next_event+0x4d/0x80 [ 68.617656][ C1] ? kvm_sched_clock_read+0x14/0x40 [ 68.622838][ C1] ? sched_clock+0x2a/0x40 [ 68.627247][ C1] ? sched_clock_cpu+0x18/0x1f0 [ 68.632089][ C1] ? hrtimer_interrupt+0x6f4/0x940 [ 68.637179][ C1] run_timer_softirq+0xb3/0x1d0 [ 68.642024][ C1] __do_softirq+0x203/0xab6 [ 68.646528][ C1] asm_call_on_stack+0xf/0x20 [ 68.651177][ C1] [ 68.654098][ C1] do_softirq_own_stack+0x9d/0xd0 [ 68.660759][ C1] irq_exit_rcu+0x235/0x280 [ 68.665263][ C1] sysvec_apic_timer_interrupt+0x51/0xf0 [ 68.670895][ C1] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 68.676853][ C1] RIP: 0010:native_safe_halt+0xe/0x10 [ 68.682206][ C1] Code: 89 ef e8 a5 99 76 f9 e9 86 fe ff ff 48 89 df e8 98 99 76 f9 e9 7b ff ff ff cc cc cc e9 07 00 00 00 0f 00 2d c4 14 49 00 fb f4 90 e9 07 00 00 00 0f 00 2d b4 14 49 00 f4 c3 cc cc 55 53 e8 09 [ 68.703821][ C1] RSP: 0018:ffffc90000d3fd80 EFLAGS: 00000293 [ 68.709866][ C1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff171e639 [ 68.717818][ C1] RDX: ffff8880a961a340 RSI: ffffffff883fd4d3 RDI: 0000000000000000 [ 68.725799][ C1] RBP: ffff88821a913064 R08: 0000000000000001 R09: 0000000000000001 [ 68.733759][ C1] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 [ 68.741747][ C1] R13: ffff88821a913000 R14: ffff88821a913064 R15: ffff8882185fc004 [ 68.749719][ C1] ? acpi_idle_do_entry+0x1e3/0x330 [ 68.754923][ C1] acpi_idle_do_entry+0x1e8/0x330 [ 68.760821][ C1] acpi_idle_enter+0x35a/0x550 [ 68.766590][ C1] cpuidle_enter_state+0x1ab/0xd20 [ 68.772305][ C1] ? tick_nohz_idle_stop_tick+0x50b/0xbd0 [ 68.778118][ C1] cpuidle_enter+0x4a/0xa0 [ 68.782547][ C1] do_idle+0x48e/0x730 [ 68.786598][ C1] ? arch_cpu_idle_exit+0x70/0x70 [ 68.791619][ C1] ? _raw_write_unlock_irqrestore+0x11/0x90 [ 68.797498][ C1] ? lockdep_hardirqs_on+0x53/0x100 [ 68.802945][ C1] cpu_startup_entry+0x14/0x20 [ 68.807707][ C1] secondary_startup_64_no_verify+0xa6/0xab [ 68.814730][ C1] Kernel Offset: disabled [ 68.819054][ C1] Rebooting in 86400 seconds..