[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ 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. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.7' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 64.835438][ C1] [ 64.837842][ C1] ======================================================== [ 64.845012][ C1] WARNING: possible irq lock inversion dependency detected [ 64.852207][ C1] 5.9.0-rc4-next-20200911-syzkaller #0 Not tainted [ 64.858696][ C1] -------------------------------------------------------- [ 64.865904][ C1] swapper/1/0 just changed the state of lock: [ 64.871961][ C1] ffff8882153c2908 (&group->lock){..-.}-{2:2}, at: _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 64.881855][ C1] but this lock took another, SOFTIRQ-READ-unsafe lock in the past: [ 64.889808][ C1] (&card->ctl_files_rwlock){.+.+}-{2:2} [ 64.889823][ C1] [ 64.889823][ C1] [ 64.889823][ C1] and interrupts could create inverse lock ordering between them. [ 64.889823][ C1] [ 64.909725][ C1] [ 64.909725][ C1] other info that might help us debug this: [ 64.917786][ C1] Possible interrupt unsafe locking scenario: [ 64.917786][ C1] [ 64.926184][ C1] CPU0 CPU1 [ 64.931543][ C1] ---- ---- [ 64.936908][ C1] lock(&card->ctl_files_rwlock); [ 64.942013][ C1] local_irq_disable(); [ 64.948757][ C1] lock(&group->lock); [ 64.955422][ C1] lock(&card->ctl_files_rwlock); [ 64.963039][ C1] [ 64.966467][ C1] lock(&group->lock); [ 64.970796][ C1] [ 64.970796][ C1] *** DEADLOCK *** [ 64.970796][ C1] [ 64.978942][ C1] 1 lock held by swapper/1/0: [ 64.983613][ C1] #0: ffffc90000da8d80 ((&dpcm->timer)){+.-.}-{0:0}, at: call_timer_fn+0xd5/0x6b0 [ 64.992889][ C1] [ 64.992889][ C1] the shortest dependencies between 2nd lock and 1st lock: [ 65.002269][ C1] -> (&card->ctl_files_rwlock){.+.+}-{2:2} { [ 65.008329][ C1] HARDIRQ-ON-R at: [ 65.012386][ C1] lock_acquire+0x1f2/0xaa0 [ 65.018693][ C1] _raw_read_lock+0x5b/0x70 [ 65.025037][ C1] snd_ctl_notify.part.0+0x36/0x550 [ 65.032129][ C1] snd_ctl_notify+0x8f/0xb0 [ 65.038449][ C1] __snd_ctl_add_replace+0x638/0x800 [ 65.045539][ C1] snd_ctl_add_replace+0x76/0x130 [ 65.053602][ C1] snd_dummy_probe+0xbbf/0x1050 [ 65.060272][ C1] platform_drv_probe+0x87/0x140 [ 65.067012][ C1] really_probe+0x282/0x9f0 [ 65.073313][ C1] driver_probe_device+0xfe/0x1d0 [ 65.080137][ C1] __device_attach_driver+0x1c2/0x220 [ 65.087307][ C1] bus_for_each_drv+0x15f/0x1e0 [ 65.093955][ C1] __device_attach+0x228/0x470 [ 65.100538][ C1] bus_probe_device+0x1e4/0x290 [ 65.107298][ C1] device_add+0xb17/0x1c40 [ 65.113517][ C1] platform_device_add+0x34f/0x6d0 [ 65.120431][ C1] platform_device_register_full+0x38c/0x4e0 [ 65.128228][ C1] alsa_card_dummy_init+0x1cc/0x2e0 [ 65.135246][ C1] do_one_initcall+0x103/0x6f0 [ 65.141820][ C1] kernel_init_freeable+0x5e9/0x66d [ 65.148816][ C1] kernel_init+0xd/0x1c0 [ 65.154867][ C1] ret_from_fork+0x1f/0x30 [ 65.161082][ C1] SOFTIRQ-ON-R at: [ 65.165130][ C1] lock_acquire+0x1f2/0xaa0 [ 65.171433][ C1] _raw_read_lock+0x5b/0x70 [ 65.177737][ C1] snd_ctl_notify.part.0+0x36/0x550 [ 65.184738][ C1] snd_ctl_notify+0x8f/0xb0 [ 65.191046][ C1] __snd_ctl_add_replace+0x638/0x800 [ 65.198152][ C1] snd_ctl_add_replace+0x76/0x130 [ 65.204986][ C1] snd_dummy_probe+0xbbf/0x1050 [ 65.211648][ C1] platform_drv_probe+0x87/0x140 [ 65.218393][ C1] really_probe+0x282/0x9f0 [ 65.224702][ C1] driver_probe_device+0xfe/0x1d0 [ 65.231531][ C1] __device_attach_driver+0x1c2/0x220 [ 65.238702][ C1] bus_for_each_drv+0x15f/0x1e0 [ 65.245353][ C1] __device_attach+0x228/0x470 [ 65.251922][ C1] bus_probe_device+0x1e4/0x290 [ 65.258573][ C1] device_add+0xb17/0x1c40 [ 65.264804][ C1] platform_device_add+0x34f/0x6d0 [ 65.271725][ C1] platform_device_register_full+0x38c/0x4e0 [ 65.279517][ C1] alsa_card_dummy_init+0x1cc/0x2e0 [ 65.286528][ C1] do_one_initcall+0x103/0x6f0 [ 65.293100][ C1] kernel_init_freeable+0x5e9/0x66d [ 65.300100][ C1] kernel_init+0xd/0x1c0 [ 65.306145][ C1] ret_from_fork+0x1f/0x30 [ 65.312360][ C1] (null) at: [ 65.315908][ C1] general protection fault, probably for non-canonical address 0xdffffc0000000002: 0000 [#1] PREEMPT SMP KASAN [ 65.327610][ C1] KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] [ 65.336000][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.9.0-rc4-next-20200911-syzkaller #0 [ 65.345080][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 65.355125][ C1] RIP: 0010:print_shortest_lock_dependencies.cold+0x110/0x2af [ 65.362575][ C1] Code: 48 8b 04 24 48 c1 e8 03 42 80 3c 20 00 74 09 48 8b 3c 24 e8 5b 11 da f9 48 8b 04 24 48 8b 00 48 8d 78 14 48 89 fa 48 c1 ea 03 <42> 0f b6 0c 22 48 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 [ 65.382162][ C1] RSP: 0018:ffffc90000da8898 EFLAGS: 00010003 [ 65.388817][ C1] RAX: 0000000000000001 RBX: ffffffff8cbdd6d0 RCX: 0000000000000000 [ 65.396797][ C1] RDX: 0000000000000002 RSI: ffffffff815c0ec7 RDI: 0000000000000015 [ 65.404776][ C1] RBP: ffffc90000da89c8 R08: 0000000000000004 R09: ffff8880ae720f8b [ 65.412745][ C1] R10: 0000000000000000 R11: 6c756e2820202020 R12: dffffc0000000000 [ 65.420719][ C1] R13: ffffffff8c9e7118 R14: 0000000000000009 R15: 0000000000000001 [ 65.428691][ C1] FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 [ 65.437613][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 65.444190][ C1] CR2: 00007fa8e9c02ab4 CR3: 0000000009c8e000 CR4: 00000000001506e0 [ 65.452146][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 65.460110][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 65.468058][ C1] Call Trace: [ 65.471343][ C1] [ 65.474183][ C1] print_irq_inversion_bug.part.0+0x2c6/0x2ee [ 65.480227][ C1] mark_lock.cold+0x38/0x10d [ 65.484798][ C1] ? lock_chain_count+0x20/0x20 [ 65.489625][ C1] ? lock_is_held_type+0xbb/0xf0 [ 65.494541][ C1] ? find_held_lock+0x2d/0x110 [ 65.499315][ C1] ? debug_object_activate+0x287/0x3e0 [ 65.504753][ C1] ? lock_downgrade+0x830/0x830 [ 65.509644][ C1] __lock_acquire+0x117d/0x55d0 [ 65.514497][ C1] ? lock_downgrade+0x830/0x830 [ 65.519413][ C1] ? lockdep_hardirqs_on_prepare+0x530/0x530 [ 65.525380][ C1] ? mark_lock+0xf7/0x2300 [ 65.529790][ C1] lock_acquire+0x1f2/0xaa0 [ 65.534271][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 65.540142][ C1] ? lock_release+0x890/0x890 [ 65.544814][ C1] ? find_held_lock+0x2d/0x110 [ 65.549568][ C1] ? loopback_jiffies_timer_function+0x188/0x220 [ 65.555890][ C1] ? _raw_spin_lock_irqsave+0xa9/0xd0 [ 65.561243][ C1] _raw_spin_lock_irqsave+0x94/0xd0 [ 65.566433][ C1] ? _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 65.572301][ C1] _snd_pcm_stream_lock_irqsave+0x9f/0xd0 [ 65.578009][ C1] snd_pcm_period_elapsed+0x24/0x250 [ 65.583271][ C1] loopback_jiffies_timer_function+0x1a8/0x220 [ 65.589416][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 65.595897][ C1] call_timer_fn+0x1a5/0x6b0 [ 65.600474][ C1] ? add_timer_on+0x450/0x450 [ 65.605250][ C1] ? lock_downgrade+0x830/0x830 [ 65.610111][ C1] ? _raw_spin_unlock_irq+0x1f/0x80 [ 65.615285][ C1] ? loopback_jiffies_timer_pos_update+0xf60/0xf60 [ 65.621762][ C1] __run_timers.part.0+0x67c/0xa50 [ 65.626857][ C1] ? call_timer_fn+0x6b0/0x6b0 [ 65.631635][ C1] ? lapic_next_event+0x4d/0x80 [ 65.636462][ C1] ? clockevents_program_event+0x12b/0x350 [ 65.642257][ C1] ? kvm_sched_clock_read+0x14/0x40 [ 65.647429][ C1] ? sched_clock+0x2a/0x40 [ 65.651856][ C1] ? sched_clock_cpu+0x18/0x1b0 [ 65.656686][ C1] ? hrtimer_interrupt+0x6ea/0x930 [ 65.661777][ C1] run_timer_softirq+0xae/0x1a0 [ 65.666621][ C1] __do_softirq+0x202/0xa42 [ 65.671112][ C1] asm_call_on_stack+0xf/0x20 [ 65.675761][ C1] [ 65.678678][ C1] do_softirq_own_stack+0x9d/0xd0 [ 65.683690][ C1] irq_exit_rcu+0x235/0x280 [ 65.688168][ C1] sysvec_apic_timer_interrupt+0x51/0xf0 [ 65.693791][ C1] asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 65.699759][ C1] RIP: 0010:native_safe_halt+0xe/0x10 [ 65.705113][ C1] Code: ff 4c 89 ef e8 93 d9 af f9 e9 8e fe ff ff 48 89 df e8 86 d9 af f9 eb 8a cc cc cc cc e9 07 00 00 00 0f 00 2d 84 87 65 00 fb f4 90 e9 07 00 00 00 0f 00 2d 74 87 65 00 f4 c3 cc cc 55 53 e8 69 [ 65.724787][ C1] RSP: 0018:ffffc90000d3fd10 EFLAGS: 00000293 [ 65.730850][ C1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 1ffffffff15cacb9 [ 65.738816][ C1] RDX: ffff8880a9630340 RSI: ffffffff88034020 RDI: 0000000000000000 [ 65.746809][ C1] RBP: ffff88821a8cf064 R08: 0000000000000001 R09: 0000000000000001 [ 65.754757][ C1] R10: 0000000000000000 R11: 0000000000000001 R12: ffff88821a8cf064 [ 65.762702][ C1] R13: 1ffff920001a7fac R14: ffff88821a8cf065 R15: 0000000000000001 [ 65.770681][ C1] ? acpi_safe_halt+0x90/0x180 [ 65.775424][ C1] acpi_safe_halt+0x95/0x180 [ 65.779989][ C1] acpi_idle_do_entry+0x15c/0x1b0 [ 65.784992][ C1] acpi_idle_enter+0x403/0xac0 [ 65.789732][ C1] ? acpi_idle_enter_bm+0x2d0/0x2d0 [ 65.794908][ C1] cpuidle_enter_state+0x150/0xa70 [ 65.800006][ C1] cpuidle_enter+0x4a/0xa0 [ 65.804411][ C1] do_idle+0x48e/0x730 [ 65.808457][ C1] ? arch_cpu_idle_exit+0x70/0x70 [ 65.813464][ C1] ? _raw_write_unlock_irqrestore+0x70/0x90 [ 65.819334][ C1] ? lockdep_hardirqs_on+0x53/0x100 [ 65.824508][ C1] cpu_startup_entry+0x14/0x20 [ 65.829335][ C1] secondary_startup_64_no_verify+0xa6/0xab [ 65.835198][ C1] Modules linked in: [ 65.839075][ C1] ---[ end trace 9ee85c02548cea79 ]--- [ 65.844512][ C1] RIP: 0010:print_shortest_lock_dependencies.cold+0x110/0x2af [ 65.851957][ C1] Code: 48 8b 04 24 48 c1 e8 03 42 80 3c 20 00 74 09 48 8b 3c 24 e8 5b 11 da f9 48 8b 04 24 48 8b 00 48 8d 78 14 48 89 fa 48 c1 ea 03 <42> 0f b6 0c 22 48 89 fa 83 e2 07 83 c2 03 38 ca 7c 08 84 c9 0f 85 [ 65.871729][ C1] RSP: 0018:ffffc90000da8898 EFLAGS: 00010003 [ 65.877776][ C1] RAX: 0000000000000001 RBX: ffffffff8cbdd6d0 RCX: 0000000000000000 [ 65.885746][ C1] RDX: 0000000000000002 RSI: ffffffff815c0ec7 RDI: 0000000000000015 [ 65.893789][ C1] RBP: ffffc90000da89c8 R08: 0000000000000004 R09: ffff8880ae720f8b [ 65.901737][ C1] R10: 0000000000000000 R11: 6c756e2820202020 R12: dffffc0000000000 [ 65.909696][ C1] R13: ffffffff8c9e7118 R14: 0000000000000009 R15: 0000000000000001 [ 65.917660][ C1] FS: 0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000 [ 65.926573][ C1] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 65.933131][ C1] CR2: 00007fa8e9c02ab4 CR3: 0000000009c8e000 CR4: 00000000001506e0 [ 65.941095][ C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 65.949045][ C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 65.957009][ C1] Kernel panic - not syncing: Fatal exception in interrupt [ 65.965329][ C1] Kernel Offset: disabled [ 65.969657][ C1] Rebooting in 86400 seconds..