Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.2' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 66.360557][ C1] [ 66.362897][ C1] ======================================================== [ 66.370081][ C1] WARNING: possible irq lock inversion dependency detected [ 66.377273][ C1] 5.9.0-rc5-next-20200918-syzkaller #0 Not tainted [ 66.383749][ C1] -------------------------------------------------------- [ 66.390919][ C1] swapper/1/0 just changed the state of lock: [ 66.396963][ C1] ffff888214e05908 (&group->lock){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 66.406854][ C1] but this lock took another, SOFTIRQ-READ-unsafe lock in the past: [ 66.414807][ C1] (&card->ctl_files_rwlock){.+.+}-{2:2} [ 66.414822][ C1] [ 66.414822][ C1] [ 66.414822][ C1] and interrupts could create inverse lock ordering between them. [ 66.414822][ C1] [ 66.434727][ C1] [ 66.434727][ C1] other info that might help us debug this: [ 66.442777][ C1] Possible interrupt unsafe locking scenario: [ 66.442777][ C1] [ 66.451096][ C1] CPU0 CPU1 [ 66.456442][ C1] ---- ---- [ 66.461787][ C1] lock(&card->ctl_files_rwlock); [ 66.466878][ C1] local_irq_disable(); [ 66.473624][ C1] lock(&group->lock); [ 66.480275][ C1] lock(&card->ctl_files_rwlock); [ 66.487881][ C1] [ 66.491312][ C1] lock(&group->lock); [ 66.495634][ C1] [ 66.495634][ C1] *** DEADLOCK *** [ 66.495634][ C1] [ 66.503756][ C1] 1 lock held by swapper/1/0: [ 66.508421][ C1] #0: ffffc90000da8d80 ((&dpcm->timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 [ 66.517716][ C1] [ 66.517716][ C1] the shortest dependencies between 2nd lock and 1st lock: [ 66.527075][ C1] -> (&card->ctl_files_rwlock){.+.+}-{2:2} { [ 66.533127][ C1] HARDIRQ-ON-R at: [ 66.537194][ C1] lock_acquire+0x1f2/0xaa0 [ 66.543520][ C1] _raw_read_lock+0x5b/0x70 [ 66.549914][ C1] snd_ctl_notify.part.0+0x36/0x550 [ 66.556918][ C1] snd_ctl_notify+0x8f/0xb0 [ 66.563226][ C1] __snd_ctl_add_replace+0x638/0x800 [ 66.570316][ C1] snd_ctl_add_replace+0x76/0x130 [ 66.577142][ C1] snd_dummy_probe+0xc22/0x1180 [ 66.583809][ C1] platform_drv_probe+0x87/0x140 [ 66.590546][ C1] really_probe+0x282/0x9f0 [ 66.596852][ C1] driver_probe_device+0xfe/0x1d0 [ 66.603691][ C1] __device_attach_driver+0x1c2/0x220 [ 66.610877][ C1] bus_for_each_drv+0x15f/0x1e0 [ 66.617530][ C1] __device_attach+0x228/0x470 [ 66.624098][ C1] bus_probe_device+0x1e4/0x290 [ 66.630753][ C1] device_add+0xb17/0x1c40 [ 66.637004][ C1] platform_device_add+0x34f/0x6d0 [ 66.643924][ C1] platform_device_register_full+0x38c/0x4e0 [ 66.651973][ C1] alsa_card_dummy_init+0x1e0/0x309 [ 66.658997][ C1] do_one_initcall+0x103/0x6f0 [ 66.665581][ C1] kernel_init_freeable+0x652/0x6d6 [ 66.672585][ C1] kernel_init+0xd/0x1b8 [ 66.678634][ C1] ret_from_fork+0x1f/0x30 [ 66.684849][ C1] SOFTIRQ-ON-R at: [ 66.688903][ C1] lock_acquire+0x1f2/0xaa0 [ 66.695216][ C1] _raw_read_lock+0x5b/0x70 [ 66.701525][ C1] snd_ctl_notify.part.0+0x36/0x550 [ 66.708558][ C1] snd_ctl_notify+0x8f/0xb0 [ 66.714889][ C1] __snd_ctl_add_replace+0x638/0x800 [ 66.721984][ C1] snd_ctl_add_replace+0x76/0x130 [ 66.728828][ C1] snd_dummy_probe+0xc22/0x1180 [ 66.735482][ C1] platform_drv_probe+0x87/0x140 [ 66.745263][ C1] really_probe+0x282/0x9f0 [ 66.751569][ C1] driver_probe_device+0xfe/0x1d0 [ 66.758412][ C1] __device_attach_driver+0x1c2/0x220 [ 66.765607][ C1] bus_for_each_drv+0x15f/0x1e0 [ 66.772256][ C1] __device_attach+0x228/0x470 [ 66.778833][ C1] bus_probe_device+0x1e4/0x290 [ 66.785483][ C1] device_add+0xb17/0x1c40 [ 66.791715][ C1] platform_device_add+0x34f/0x6d0 [ 66.798631][ C1] platform_device_register_full+0x38c/0x4e0 [ 66.806426][ C1] alsa_card_dummy_init+0x1e0/0x309 [ 66.813441][ C1] do_one_initcall+0x103/0x6f0 [ 66.820021][ C1] kernel_init_freeable+0x652/0x6d6 [ 66.827075][ C1] kernel_init+0xd/0x1b8 [ 66.833133][ C1] ret_from_fork+0x1f/0x30 [ 66.839354][ C1] (null) at: [ 66.842879][ C1] ================================================================================ [ 66.852187][ C1] UBSAN: array-index-out-of-bounds in kernel/locking/lockdep.c:2240:40 [ 66.860403][ C1] index 9 is out of range for type 'lock_trace *[9]' [ 66.867094][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0-rc5-next-20200918-syzkaller #0 [ 66.876183][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 66.886217][ C1] Call Trace: [ 66.889478][ C1] [ 66.892310][ C1] dump_stack+0x198/0x1fb [ 66.896613][ C1] ubsan_epilogue+0xb/0x5a [ 66.901103][ C1] __ubsan_handle_out_of_bounds.cold+0x62/0x6c [ 66.907255][ C1] ? vprintk_func+0x95/0x1e0 [ 66.911836][ C1] print_shortest_lock_dependencies.cold+0x11c/0x2e2 [ 66.918498][ C1] print_irq_inversion_bug.part.0+0x2c6/0x2ee [ 66.924545][ C1] mark_lock.cold+0x57/0x74 [ 66.929027][ C1] ? lock_chain_count+0x20/0x20 [ 66.933870][ C1] ? lock_is_held_type+0xbb/0xf0 [ 66.938796][ C1] ? find_held_lock+0x2d/0x110 [ 66.943556][ C1] ? debug_object_activate+0x287/0x3e0 [ 66.948995][ C1] ? lock_downgrade+0x830/0x830 [ 66.953839][ C1] __lock_acquire+0x118a/0x56d0 [ 66.958668][ C1] ? lock_downgrade+0x830/0x830 [ 66.963510][ C1] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 66.969466][ C1] ? mark_lock+0xf7/0x2420 [ 66.973873][ C1] lock_acquire+0x1f2/0xaa0 [ 66.978356][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 66.984225][ C1] ? lock_release+0x890/0x890 [ 66.988876][ C1] ? find_held_lock+0x2d/0x110 [ 66.993617][ C1] ? loopback_jiffies_timer_function+0x188/0x220 [ 66.999923][ C1] ? _raw_spin_lock_irqsave+0xa9/0xd0 [ 67.005268][ C1] _raw_spin_lock_irqsave+0x94/0xd0 [ 67.010460][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 67.016343][ C1] _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 67.022038][ C1] snd_pcm_period_elapsed+0x24/0x250 [ 67.027319][ C1] loopback_jiffies_timer_function+0x1a8/0x220 [ 67.033464][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 67.039955][ C1] call_timer_fn+0x1a5/0x6b0 [ 67.044526][ C1] ? add_timer_on+0x4a0/0x4a0 [ 67.049183][ C1] ? lock_downgrade+0x830/0x830 [ 67.054015][ C1] ? _raw_spin_unlock_irq+0x1f/0x80 [ 67.059195][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 67.065676][ C1] __run_timers.part.0+0x67c/0xa50 [ 67.070770][ C1] ? call_timer_fn+0x6b0/0x6b0 [ 67.076137][ C1] ? lapic_next_event+0x4d/0x80 [ 67.080970][ C1] ? kvm_sched_clock_read+0x14/0x40 [ 67.086144][ C1] ? sched_clock+0x2a/0x40 [ 67.090539][ C1] ? sched_clock_cpu+0x18/0x1f0 [ 67.095370][ C1] ? hrtimer_interrupt+0x6f4/0x940 [ 67.100460][ C1] run_timer_softirq+0xb3/0x1d0 [ 67.105302][ C1] __do_softirq+0x203/0xab6 [ 67.109798][ C1] asm_call_on_stack+0xf/0x20 [ 67.114464][ C1] [ 67.117384][ C1] do_softirq_own_stack+0x9d/0xd0 [ 67.122408][ C1] irq_exit_rcu+0x235/0x280 [ 67.126890][ C1] sysvec_apic_timer_interrupt+0x51/0xf0 [ 67.132502][ C1] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 67.138726][ C1] RIP: 0010:native_safe_halt+0xe/0x10 [ 67.144083][ 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 [ 67.163679][ C1] RSP: 0018:ffffc90000d3fd80 EFLAGS: 00000293 [ 67.169731][ C1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff171e639 [ 67.177704][ C1] RDX: ffff8880a961a340 RSI: ffffffff883fd4d3 RDI: 0000000000000000 [ 67.185656][ C1] RBP: ffff8880a668e064 R08: 0000000000000001 R09: 0000000000000001 [ 67.193607][ C1] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 [ 67.201564][ C1] R13: ffff8880a668e000 R14: ffff8880a668e064 R15: ffff888219311804 [ 67.209530][ C1] ? acpi_idle_do_entry+0x1e3/0x330 [ 67.214723][ C1] acpi_idle_do_entry+0x1e8/0x330 [ 67.219742][ C1] acpi_idle_enter+0x35a/0x550 [ 67.224509][ C1] cpuidle_enter_state+0x1ab/0xd20 [ 67.230309][ C1] ? tick_nohz_idle_stop_tick+0x50b/0xbd0 [ 67.236051][ C1] cpuidle_enter+0x4a/0xa0 [ 67.240467][ C1] do_idle+0x48e/0x730 [ 67.244523][ C1] ? arch_cpu_idle_exit+0x70/0x70 [ 67.249524][ C1] ? _raw_write_unlock_irqrestore+0x11/0x90 [ 67.255409][ C1] ? lockdep_hardirqs_on+0x53/0x100 [ 67.260597][ C1] cpu_startup_entry+0x14/0x20 [ 67.265362][ C1] secondary_startup_64_no_verify+0xa6/0xab [ 67.271249][ C1] ================================================================================ [ 67.280529][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 67.287115][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0-rc5-next-20200918-syzkaller #0 [ 67.296240][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 67.306282][ C1] Call Trace: [ 67.309552][ C1] [ 67.312406][ C1] dump_stack+0x198/0x1fb [ 67.316715][ C1] panic+0x382/0x7fb [ 67.320595][ C1] ? __warn_printk+0xf3/0xf3 [ 67.325171][ C1] ? secondary_startup_64_no_verify+0xa6/0xab [ 67.331234][ C1] ? ubsan_epilogue+0x3e/0x5a [ 67.335895][ C1] ? ubsan_epilogue+0x35/0x5a [ 67.340563][ C1] ubsan_epilogue+0x54/0x5a [ 67.345046][ C1] __ubsan_handle_out_of_bounds.cold+0x62/0x6c [ 67.351191][ C1] ? vprintk_func+0x95/0x1e0 [ 67.355759][ C1] print_shortest_lock_dependencies.cold+0x11c/0x2e2 [ 67.362433][ C1] print_irq_inversion_bug.part.0+0x2c6/0x2ee [ 67.368481][ C1] mark_lock.cold+0x57/0x74 [ 67.373052][ C1] ? lock_chain_count+0x20/0x20 [ 67.377907][ C1] ? lock_is_held_type+0xbb/0xf0 [ 67.382833][ C1] ? find_held_lock+0x2d/0x110 [ 67.387588][ C1] ? debug_object_activate+0x287/0x3e0 [ 67.393038][ C1] ? lock_downgrade+0x830/0x830 [ 67.397872][ C1] __lock_acquire+0x118a/0x56d0 [ 67.402701][ C1] ? lock_downgrade+0x830/0x830 [ 67.407543][ C1] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 67.413559][ C1] ? mark_lock+0xf7/0x2420 [ 67.419527][ C1] lock_acquire+0x1f2/0xaa0 [ 67.424014][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 67.429894][ C1] ? lock_release+0x890/0x890 [ 67.434553][ C1] ? find_held_lock+0x2d/0x110 [ 67.439301][ C1] ? loopback_jiffies_timer_function+0x188/0x220 [ 67.445618][ C1] ? _raw_spin_lock_irqsave+0xa9/0xd0 [ 67.450978][ C1] _raw_spin_lock_irqsave+0x94/0xd0 [ 67.456158][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 67.462087][ C1] _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 67.467791][ C1] snd_pcm_period_elapsed+0x24/0x250 [ 67.473059][ C1] loopback_jiffies_timer_function+0x1a8/0x220 [ 67.479209][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 67.485691][ C1] call_timer_fn+0x1a5/0x6b0 [ 67.490261][ C1] ? add_timer_on+0x4a0/0x4a0 [ 67.494914][ C1] ? lock_downgrade+0x830/0x830 [ 67.499757][ C1] ? _raw_spin_unlock_irq+0x1f/0x80 [ 67.504942][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 67.511426][ C1] __run_timers.part.0+0x67c/0xa50 [ 67.516518][ C1] ? call_timer_fn+0x6b0/0x6b0 [ 67.521275][ C1] ? lapic_next_event+0x4d/0x80 [ 67.526117][ C1] ? kvm_sched_clock_read+0x14/0x40 [ 67.531911][ C1] ? sched_clock+0x2a/0x40 [ 67.536316][ C1] ? sched_clock_cpu+0x18/0x1f0 [ 67.541146][ C1] ? hrtimer_interrupt+0x6f4/0x940 [ 67.546238][ C1] run_timer_softirq+0xb3/0x1d0 [ 67.551068][ C1] __do_softirq+0x203/0xab6 [ 67.555632][ C1] asm_call_on_stack+0xf/0x20 [ 67.560283][ C1] [ 67.563219][ C1] do_softirq_own_stack+0x9d/0xd0 [ 67.568221][ C1] irq_exit_rcu+0x235/0x280 [ 67.572722][ C1] sysvec_apic_timer_interrupt+0x51/0xf0 [ 67.578945][ C1] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 67.584909][ C1] RIP: 0010:native_safe_halt+0xe/0x10 [ 67.590257][ 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 [ 67.609852][ C1] RSP: 0018:ffffc90000d3fd80 EFLAGS: 00000293 [ 67.615912][ C1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff171e639 [ 67.624558][ C1] RDX: ffff8880a961a340 RSI: ffffffff883fd4d3 RDI: 0000000000000000 [ 67.632525][ C1] RBP: ffff8880a668e064 R08: 0000000000000001 R09: 0000000000000001 [ 67.640487][ C1] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 [ 67.648438][ C1] R13: ffff8880a668e000 R14: ffff8880a668e064 R15: ffff888219311804 [ 67.656435][ C1] ? acpi_idle_do_entry+0x1e3/0x330 [ 67.661621][ C1] acpi_idle_do_entry+0x1e8/0x330 [ 67.666625][ C1] acpi_idle_enter+0x35a/0x550 [ 67.671384][ C1] cpuidle_enter_state+0x1ab/0xd20 [ 67.676482][ C1] ? tick_nohz_idle_stop_tick+0x50b/0xbd0 [ 67.682192][ C1] cpuidle_enter+0x4a/0xa0 [ 67.686591][ C1] do_idle+0x48e/0x730 [ 67.690658][ C1] ? arch_cpu_idle_exit+0x70/0x70 [ 67.695672][ C1] ? _raw_write_unlock_irqrestore+0x11/0x90 [ 67.701549][ C1] ? lockdep_hardirqs_on+0x53/0x100 [ 67.706733][ C1] cpu_startup_entry+0x14/0x20 [ 67.711491][ C1] secondary_startup_64_no_verify+0xa6/0xab [ 67.718493][ C1] Kernel Offset: disabled [ 67.722890][ C1] Rebooting in 86400 seconds..