[ 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 '10.128.0.67' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 63.736590][ C1] [ 63.738977][ C1] ======================================================== [ 63.746153][ C1] WARNING: possible irq lock inversion dependency detected [ 63.753330][ C1] 5.9.0-rc5-next-20200921-syzkaller #0 Not tainted [ 63.759809][ C1] -------------------------------------------------------- [ 63.766970][ C1] swapper/1/0 just changed the state of lock: [ 63.773003][ C1] ffff888214c9f908 (&group->lock){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 63.782879][ C1] but this lock took another, SOFTIRQ-READ-unsafe lock in the past: [ 63.790821][ C1] (&card->ctl_files_rwlock){.+.+}-{2:2} [ 63.790833][ C1] [ 63.790833][ C1] [ 63.790833][ C1] and interrupts could create inverse lock ordering between them. [ 63.790833][ C1] [ 63.810722][ C1] [ 63.810722][ C1] other info that might help us debug this: [ 63.818765][ C1] Possible interrupt unsafe locking scenario: [ 63.818765][ C1] [ 63.827056][ C1] CPU0 CPU1 [ 63.832396][ C1] ---- ---- [ 63.837733][ C1] lock(&card->ctl_files_rwlock); [ 63.842833][ C1] local_irq_disable(); [ 63.849569][ C1] lock(&group->lock); [ 63.856228][ C1] lock(&card->ctl_files_rwlock); [ 63.863843][ C1] [ 63.867288][ C1] lock(&group->lock); [ 63.871604][ C1] [ 63.871604][ C1] *** DEADLOCK *** [ 63.871604][ C1] [ 63.879721][ C1] 1 lock held by swapper/1/0: [ 63.884368][ C1] #0: ffffc90000da8d80 ((&dpcm->timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 [ 63.893640][ C1] [ 63.893640][ C1] the shortest dependencies between 2nd lock and 1st lock: [ 63.904043][ C1] -> (&card->ctl_files_rwlock){.+.+}-{2:2} { [ 63.910126][ C1] HARDIRQ-ON-R at: [ 63.914171][ C1] lock_acquire+0x1f2/0xaa0 [ 63.920494][ C1] _raw_read_lock+0x5b/0x70 [ 63.926793][ C1] snd_ctl_notify.part.0+0x36/0x550 [ 63.934230][ C1] snd_ctl_notify+0x8f/0xb0 [ 63.940540][ C1] __snd_ctl_add_replace+0x638/0x800 [ 63.947633][ C1] snd_ctl_add_replace+0x76/0x130 [ 63.954465][ C1] snd_dummy_probe+0xc22/0x1180 [ 63.961120][ C1] platform_drv_probe+0x87/0x140 [ 63.967857][ C1] really_probe+0x282/0x9f0 [ 63.974156][ C1] driver_probe_device+0xfe/0x1d0 [ 63.980974][ C1] __device_attach_driver+0x1c2/0x220 [ 63.988145][ C1] bus_for_each_drv+0x15f/0x1e0 [ 63.994801][ C1] __device_attach+0x228/0x470 [ 64.001354][ C1] bus_probe_device+0x1e4/0x290 [ 64.007996][ C1] device_add+0xb17/0x1c40 [ 64.014205][ C1] platform_device_add+0x34f/0x6d0 [ 64.021121][ C1] platform_device_register_full+0x38c/0x4e0 [ 64.028914][ C1] alsa_card_dummy_init+0x1e0/0x309 [ 64.035907][ C1] do_one_initcall+0x103/0x6f0 [ 64.042477][ C1] kernel_init_freeable+0x652/0x6d6 [ 64.049477][ C1] kernel_init+0xd/0x1b8 [ 64.055511][ C1] ret_from_fork+0x1f/0x30 [ 64.061715][ C1] SOFTIRQ-ON-R at: [ 64.065757][ C1] lock_acquire+0x1f2/0xaa0 [ 64.072053][ C1] _raw_read_lock+0x5b/0x70 [ 64.078349][ C1] snd_ctl_notify.part.0+0x36/0x550 [ 64.085339][ C1] snd_ctl_notify+0x8f/0xb0 [ 64.091645][ C1] __snd_ctl_add_replace+0x638/0x800 [ 64.098730][ C1] snd_ctl_add_replace+0x76/0x130 [ 64.105547][ C1] snd_dummy_probe+0xc22/0x1180 [ 64.112200][ C1] platform_drv_probe+0x87/0x140 [ 64.118930][ C1] really_probe+0x282/0x9f0 [ 64.125224][ C1] driver_probe_device+0xfe/0x1d0 [ 64.132041][ C1] __device_attach_driver+0x1c2/0x220 [ 64.139206][ C1] bus_for_each_drv+0x15f/0x1e0 [ 64.145846][ C1] __device_attach+0x228/0x470 [ 64.152401][ C1] bus_probe_device+0x1e4/0x290 [ 64.159055][ C1] device_add+0xb17/0x1c40 [ 64.165271][ C1] platform_device_add+0x34f/0x6d0 [ 64.172291][ C1] platform_device_register_full+0x38c/0x4e0 [ 64.180063][ C1] alsa_card_dummy_init+0x1e0/0x309 [ 64.187072][ C1] do_one_initcall+0x103/0x6f0 [ 64.193639][ C1] kernel_init_freeable+0x652/0x6d6 [ 64.200763][ C1] kernel_init+0xd/0x1b8 [ 64.206804][ C1] ret_from_fork+0x1f/0x30 [ 64.213012][ C1] (null) at: [ 64.216532][ C1] ================================================================================ [ 64.225779][ C1] UBSAN: array-index-out-of-bounds in kernel/locking/lockdep.c:2240:40 [ 64.234015][ C1] index 9 is out of range for type 'lock_trace *[9]' [ 64.240662][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0-rc5-next-20200921-syzkaller #0 [ 64.249747][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 64.259772][ C1] Call Trace: [ 64.263027][ C1] [ 64.265854][ C1] dump_stack+0x198/0x1fb [ 64.270154][ C1] ubsan_epilogue+0xb/0x5a [ 64.274542][ C1] __ubsan_handle_out_of_bounds.cold+0x62/0x6c [ 64.280666][ C1] ? vprintk_func+0x95/0x1e0 [ 64.285239][ C1] print_shortest_lock_dependencies.cold+0x11c/0x2e2 [ 64.291903][ C1] print_irq_inversion_bug.part.0+0x2c6/0x2ee [ 64.297949][ C1] mark_lock.cold+0x57/0x74 [ 64.302434][ C1] ? lock_chain_count+0x20/0x20 [ 64.307254][ C1] ? lock_is_held_type+0xbb/0xf0 [ 64.312159][ C1] ? find_held_lock+0x2d/0x110 [ 64.316900][ C1] ? debug_object_activate+0x287/0x3e0 [ 64.322328][ C1] ? lock_downgrade+0x830/0x830 [ 64.327149][ C1] __lock_acquire+0x118a/0x56d0 [ 64.331981][ C1] ? lock_downgrade+0x830/0x830 [ 64.336813][ C1] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 64.342774][ C1] ? mark_lock+0xf7/0x2420 [ 64.347178][ C1] lock_acquire+0x1f2/0xaa0 [ 64.351723][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 64.357599][ C1] ? lock_release+0x890/0x890 [ 64.362251][ C1] ? find_held_lock+0x2d/0x110 [ 64.367030][ C1] ? loopback_jiffies_timer_function+0x188/0x220 [ 64.373330][ C1] ? _raw_spin_lock_irqsave+0xa9/0xd0 [ 64.378673][ C1] _raw_spin_lock_irqsave+0x94/0xd0 [ 64.383849][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 64.389744][ C1] _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 64.395448][ C1] snd_pcm_period_elapsed+0x24/0x250 [ 64.400704][ C1] loopback_jiffies_timer_function+0x1a8/0x220 [ 64.406829][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 64.413297][ C1] call_timer_fn+0x1a5/0x6b0 [ 64.417867][ C1] ? add_timer_on+0x4a0/0x4a0 [ 64.422527][ C1] ? lock_downgrade+0x830/0x830 [ 64.427369][ C1] ? rwlock_bug.part.0+0x90/0x90 [ 64.432296][ C1] ? _raw_spin_unlock_irq+0x1f/0x80 [ 64.437480][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 64.443996][ C1] __run_timers.part.0+0x67c/0xa50 [ 64.449082][ C1] ? call_timer_fn+0x6b0/0x6b0 [ 64.453955][ C1] ? lapic_next_event+0x4d/0x80 [ 64.458796][ C1] ? kvm_sched_clock_read+0x14/0x40 [ 64.463975][ C1] ? sched_clock+0x2a/0x40 [ 64.468421][ C1] ? sched_clock_cpu+0x18/0x1f0 [ 64.473263][ C1] ? hrtimer_interrupt+0x6f4/0x940 [ 64.478352][ C1] run_timer_softirq+0xb3/0x1d0 [ 64.483181][ C1] __do_softirq+0x203/0xab6 [ 64.487665][ C1] asm_call_on_stack+0xf/0x20 [ 64.492314][ C1] [ 64.495230][ C1] do_softirq_own_stack+0x9d/0xd0 [ 64.500225][ C1] irq_exit_rcu+0x235/0x280 [ 64.504698][ C1] sysvec_apic_timer_interrupt+0x51/0xf0 [ 64.510315][ C1] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 64.516274][ C1] RIP: 0010:native_safe_halt+0xe/0x10 [ 64.521630][ C1] Code: 89 ef e8 15 61 76 f9 e9 86 fe ff ff 48 89 df e8 08 61 76 f9 e9 7b ff ff ff cc cc cc e9 07 00 00 00 0f 00 2d 74 b8 68 00 fb f4 90 e9 07 00 00 00 0f 00 2d 64 b8 68 00 f4 c3 cc cc 55 53 e8 09 [ 64.541214][ C1] RSP: 0018:ffffc90000d3fd80 EFLAGS: 00000293 [ 64.547250][ C1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff175e959 [ 64.555193][ C1] RDX: ffff8880a961a340 RSI: ffffffff88403123 RDI: 0000000000000000 [ 64.563144][ C1] RBP: ffff8880a6313864 R08: 0000000000000001 R09: 0000000000000001 [ 64.571102][ C1] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 [ 64.579045][ C1] R13: ffff8880a6313800 R14: ffff8880a6313864 R15: ffff888218624004 [ 64.586993][ C1] ? acpi_idle_do_entry+0x1e3/0x330 [ 64.592162][ C1] acpi_idle_do_entry+0x1e8/0x330 [ 64.597169][ C1] acpi_idle_enter+0x35a/0x550 [ 64.601922][ C1] cpuidle_enter_state+0x1ab/0xd20 [ 64.607022][ C1] cpuidle_enter+0x4a/0xa0 [ 64.611414][ C1] do_idle+0x48e/0x730 [ 64.615454][ C1] ? arch_cpu_idle_exit+0x70/0x70 [ 64.620449][ C1] cpu_startup_entry+0x14/0x20 [ 64.625194][ C1] secondary_startup_64_no_verify+0xa6/0xab [ 64.631059][ C1] ================================================================================ [ 64.640306][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 64.646863][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0-rc5-next-20200921-syzkaller #0 [ 64.655935][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 64.665959][ C1] Call Trace: [ 64.669253][ C1] [ 64.672094][ C1] dump_stack+0x198/0x1fb [ 64.676397][ C1] panic+0x382/0x7fb [ 64.680309][ C1] ? __warn_printk+0xf3/0xf3 [ 64.684897][ C1] ? secondary_startup_64_no_verify+0xa6/0xab [ 64.690963][ C1] ? ubsan_epilogue+0x3e/0x5a [ 64.695610][ C1] ? ubsan_epilogue+0x35/0x5a [ 64.700258][ C1] ubsan_epilogue+0x54/0x5a [ 64.704733][ C1] __ubsan_handle_out_of_bounds.cold+0x62/0x6c [ 64.710872][ C1] ? vprintk_func+0x95/0x1e0 [ 64.715448][ C1] print_shortest_lock_dependencies.cold+0x11c/0x2e2 [ 64.722094][ C1] print_irq_inversion_bug.part.0+0x2c6/0x2ee [ 64.728130][ C1] mark_lock.cold+0x57/0x74 [ 64.732617][ C1] ? lock_chain_count+0x20/0x20 [ 64.737449][ C1] ? lock_is_held_type+0xbb/0xf0 [ 64.742379][ C1] ? find_held_lock+0x2d/0x110 [ 64.747118][ C1] ? debug_object_activate+0x287/0x3e0 [ 64.752549][ C1] ? lock_downgrade+0x830/0x830 [ 64.757402][ C1] __lock_acquire+0x118a/0x56d0 [ 64.762239][ C1] ? lock_downgrade+0x830/0x830 [ 64.767076][ C1] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 64.773024][ C1] ? mark_lock+0xf7/0x2420 [ 64.777414][ C1] lock_acquire+0x1f2/0xaa0 [ 64.781891][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 64.787793][ C1] ? lock_release+0x890/0x890 [ 64.792439][ C1] ? find_held_lock+0x2d/0x110 [ 64.797175][ C1] ? loopback_jiffies_timer_function+0x188/0x220 [ 64.803475][ C1] ? _raw_spin_lock_irqsave+0xa9/0xd0 [ 64.808832][ C1] _raw_spin_lock_irqsave+0x94/0xd0 [ 64.814020][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 64.819896][ C1] _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 64.825586][ C1] snd_pcm_period_elapsed+0x24/0x250 [ 64.830843][ C1] loopback_jiffies_timer_function+0x1a8/0x220 [ 64.836967][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 64.843434][ C1] call_timer_fn+0x1a5/0x6b0 [ 64.847993][ C1] ? add_timer_on+0x4a0/0x4a0 [ 64.852640][ C1] ? lock_downgrade+0x830/0x830 [ 64.857475][ C1] ? rwlock_bug.part.0+0x90/0x90 [ 64.862381][ C1] ? _raw_spin_unlock_irq+0x1f/0x80 [ 64.867549][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 64.874021][ C1] __run_timers.part.0+0x67c/0xa50 [ 64.879104][ C1] ? call_timer_fn+0x6b0/0x6b0 [ 64.883843][ C1] ? lapic_next_event+0x4d/0x80 [ 64.888666][ C1] ? kvm_sched_clock_read+0x14/0x40 [ 64.893852][ C1] ? sched_clock+0x2a/0x40 [ 64.898238][ C1] ? sched_clock_cpu+0x18/0x1f0 [ 64.903075][ C1] ? hrtimer_interrupt+0x6f4/0x940 [ 64.908170][ C1] run_timer_softirq+0xb3/0x1d0 [ 64.913006][ C1] __do_softirq+0x203/0xab6 [ 64.917490][ C1] asm_call_on_stack+0xf/0x20 [ 64.922133][ C1] [ 64.925056][ C1] do_softirq_own_stack+0x9d/0xd0 [ 64.930051][ C1] irq_exit_rcu+0x235/0x280 [ 64.934796][ C1] sysvec_apic_timer_interrupt+0x51/0xf0 [ 64.940400][ C1] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 64.946369][ C1] RIP: 0010:native_safe_halt+0xe/0x10 [ 64.951712][ C1] Code: 89 ef e8 15 61 76 f9 e9 86 fe ff ff 48 89 df e8 08 61 76 f9 e9 7b ff ff ff cc cc cc e9 07 00 00 00 0f 00 2d 74 b8 68 00 fb f4 90 e9 07 00 00 00 0f 00 2d 64 b8 68 00 f4 c3 cc cc 55 53 e8 09 [ 64.971285][ C1] RSP: 0018:ffffc90000d3fd80 EFLAGS: 00000293 [ 64.977322][ C1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff175e959 [ 64.985263][ C1] RDX: ffff8880a961a340 RSI: ffffffff88403123 RDI: 0000000000000000 [ 64.993204][ C1] RBP: ffff8880a6313864 R08: 0000000000000001 R09: 0000000000000001 [ 65.001147][ C1] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000001 [ 65.009090][ C1] R13: ffff8880a6313800 R14: ffff8880a6313864 R15: ffff888218624004 [ 65.017038][ C1] ? acpi_idle_do_entry+0x1e3/0x330 [ 65.022218][ C1] acpi_idle_do_entry+0x1e8/0x330 [ 65.027216][ C1] acpi_idle_enter+0x35a/0x550 [ 65.031963][ C1] cpuidle_enter_state+0x1ab/0xd20 [ 65.037045][ C1] cpuidle_enter+0x4a/0xa0 [ 65.041438][ C1] do_idle+0x48e/0x730 [ 65.045479][ C1] ? arch_cpu_idle_exit+0x70/0x70 [ 65.050475][ C1] cpu_startup_entry+0x14/0x20 [ 65.055210][ C1] secondary_startup_64_no_verify+0xa6/0xab [ 65.062442][ C1] Kernel Offset: disabled [ 65.066769][ C1] Rebooting in 86400 seconds..