delete_channel: no stack delete_channel: no stack ======================================================== WARNING: possible irq lock inversion dependency detected 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Not tainted -------------------------------------------------------- syz-executor.1/5363 just changed the state of lock: ffff888029007948 (&timer->lock){+.+.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline] ffff888029007948 (&timer->lock){+.+.}-{2:2}, at: class_spinlock_constructor include/linux/spinlock.h:561 [inline] ffff888029007948 (&timer->lock){+.+.}-{2:2}, at: snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 but this lock was taken by another, SOFTIRQ-safe lock in the past: (&group->lock#2){..-.}-{2:2} and interrupts could create inverse lock ordering between them. other info that might help us debug this: Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&timer->lock); local_irq_disable(); lock(&group->lock#2); lock(&timer->lock); lock(&group->lock#2); *** DEADLOCK *** 3 locks held by syz-executor.1/5363: #0: ffffffff8f2e5728 (register_mutex#4){+.+.}-{3:3}, at: odev_release+0x4e/0x80 sound/core/seq/oss/seq_oss.c:143 #1: ffff88802aef5578 (&q->timer_mutex){+.+.}-{3:3}, at: queue_delete sound/core/seq/seq_queue.c:124 [inline] #1: ffff88802aef5578 (&q->timer_mutex){+.+.}-{3:3}, at: snd_seq_queue_delete+0x5b/0xf0 sound/core/seq/seq_queue.c:188 #2: ffffffff8f2d3f68 (register_mutex){+.+.}-{3:3}, at: class_mutex_constructor include/linux/mutex.h:169 [inline] #2: ffffffff8f2d3f68 (register_mutex){+.+.}-{3:3}, at: snd_timer_close+0xa3/0x130 sound/core/timer.c:463 the shortest dependencies between 2nd lock and 1st lock: -> (&group->lock#2){..-.}-{2:2} { IN-SOFTIRQ-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_pcm_stream_lock_irqsave_constructor include/sound/pcm.h:669 [inline] snd_pcm_period_elapsed+0x21/0x50 sound/core/pcm_lib.c:1904 call_timer_fn+0x17e/0x600 kernel/time/timer.c:1792 expire_timers kernel/time/timer.c:1843 [inline] __run_timers kernel/time/timer.c:2408 [inline] __run_timer_base+0x66a/0x8e0 kernel/time/timer.c:2419 run_timer_base kernel/time/timer.c:2428 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2438 __do_softirq+0x2bc/0x943 kernel/softirq.c:554 invoke_softirq kernel/softirq.c:428 [inline] __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633 irq_exit_rcu+0x9/0x30 kernel/softirq.c:645 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0xd8/0x140 kernel/locking/spinlock.c:194 __debug_check_no_obj_freed lib/debugobjects.c:998 [inline] debug_check_no_obj_freed+0x561/0x580 lib/debugobjects.c:1019 slab_free_hook mm/slub.c:2078 [inline] slab_free mm/slub.c:4280 [inline] kmem_cache_free+0xcc/0x2b0 mm/slub.c:4344 __dentry_kill+0x497/0x630 fs/dcache.c:622 dput+0x19f/0x2b0 fs/dcache.c:845 __fput+0x678/0x8a0 fs/file_table.c:430 __do_sys_close fs/open.c:1556 [inline] __se_sys_close fs/open.c:1541 [inline] __ia32_sys_close+0x7f/0x110 fs/open.c:1541 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 INITIAL USE at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline] _raw_spin_lock_irq+0xd3/0x120 kernel/locking/spinlock.c:170 spin_lock_irq include/linux/spinlock.h:376 [inline] snd_pcm_group_lock_irq sound/core/pcm_native.c:97 [inline] snd_pcm_stream_lock_irq sound/core/pcm_native.c:136 [inline] class_pcm_stream_lock_irq_constructor include/sound/pcm.h:666 [inline] snd_pcm_hw_params+0x201/0x1ea0 sound/core/pcm_native.c:740 snd_pcm_oss_change_params_locked+0x20d5/0x3e00 sound/core/oss/pcm_oss.c:965 snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1105 [inline] snd_pcm_oss_get_active_substream+0x201/0x280 sound/core/oss/pcm_oss.c:1122 snd_pcm_oss_get_rate sound/core/oss/pcm_oss.c:1778 [inline] snd_pcm_oss_set_rate+0x248/0x5d0 sound/core/oss/pcm_oss.c:1770 snd_pcm_oss_ioctl+0xe31/0xff0 sound/core/oss/pcm_oss.c:2623 __do_compat_sys_ioctl fs/ioctl.c:1004 [inline] __se_compat_sys_ioctl+0x51c/0xca0 fs/ioctl.c:947 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 } ... key at: [] snd_pcm_group_init.__key+0x0/0x20 ... acquired at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:574 [inline] snd_timer_notify+0x103/0x3d0 sound/core/timer.c:1040 snd_pcm_action sound/core/pcm_native.c:1370 [inline] snd_pcm_action_lock_irq+0x1b5/0x290 sound/core/pcm_native.c:1383 snd_pcm_oss_set_trigger+0x580/0x730 sound/core/oss/pcm_oss.c:2134 snd_pcm_oss_poll+0x668/0x8c0 sound/core/oss/pcm_oss.c:2863 vfs_poll include/linux/poll.h:84 [inline] do_pollfd fs/select.c:873 [inline] do_poll fs/select.c:921 [inline] do_sys_poll+0x7e4/0x1330 fs/select.c:1016 __do_compat_sys_ppoll_time32 fs/select.c:1420 [inline] __se_compat_sys_ppoll_time32+0x2a2/0x330 fs/select.c:1400 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 -> (&timer->lock){+.+.}-{2:2} { HARDIRQ-ON-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 snd_timer_close+0xae/0x130 sound/core/timer.c:464 snd_seq_timer_close+0xa9/0xe0 sound/core/seq/seq_timer.c:302 queue_delete sound/core/seq/seq_queue.c:126 [inline] snd_seq_queue_delete+0x8f/0xf0 sound/core/seq/seq_queue.c:188 delete_seq_queue sound/core/seq/oss/seq_oss_init.c:371 [inline] snd_seq_oss_release+0x1d3/0x310 sound/core/seq/oss/seq_oss_init.c:416 odev_release+0x56/0x80 sound/core/seq/oss/seq_oss.c:144 __fput+0x429/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa1b/0x27e0 kernel/exit.c:878 do_group_exit+0x207/0x2c0 kernel/exit.c:1027 get_signal+0x176e/0x1850 kernel/signal.c:2907 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0xc9/0x360 kernel/entry/common.c:212 __do_fast_syscall_32+0xd0/0x120 arch/x86/entry/common.c:324 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 SOFTIRQ-ON-W at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 snd_timer_close+0xae/0x130 sound/core/timer.c:464 snd_seq_timer_close+0xa9/0xe0 sound/core/seq/seq_timer.c:302 queue_delete sound/core/seq/seq_queue.c:126 [inline] snd_seq_queue_delete+0x8f/0xf0 sound/core/seq/seq_queue.c:188 delete_seq_queue sound/core/seq/oss/seq_oss_init.c:371 [inline] snd_seq_oss_release+0x1d3/0x310 sound/core/seq/oss/seq_oss_init.c:416 odev_release+0x56/0x80 sound/core/seq/oss/seq_oss.c:144 __fput+0x429/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa1b/0x27e0 kernel/exit.c:878 do_group_exit+0x207/0x2c0 kernel/exit.c:1027 get_signal+0x176e/0x1850 kernel/signal.c:2907 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0xc9/0x360 kernel/entry/common.c:212 __do_fast_syscall_32+0xd0/0x120 arch/x86/entry/common.c:324 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 INITIAL USE at: lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xd5/0x120 kernel/locking/spinlock.c:162 class_spinlock_irqsave_constructor include/linux/spinlock.h:574 [inline] snd_timer_notify+0x103/0x3d0 sound/core/timer.c:1040 snd_pcm_action sound/core/pcm_native.c:1370 [inline] snd_pcm_action_lock_irq+0x1b5/0x290 sound/core/pcm_native.c:1383 snd_pcm_oss_set_trigger+0x580/0x730 sound/core/oss/pcm_oss.c:2134 snd_pcm_oss_poll+0x668/0x8c0 sound/core/oss/pcm_oss.c:2863 vfs_poll include/linux/poll.h:84 [inline] do_pollfd fs/select.c:873 [inline] do_poll fs/select.c:921 [inline] do_sys_poll+0x7e4/0x1330 fs/select.c:1016 __do_compat_sys_ppoll_time32 fs/select.c:1420 [inline] __se_compat_sys_ppoll_time32+0x2a2/0x330 fs/select.c:1400 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xbe/0x120 arch/x86/entry/common.c:321 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 } ... key at: [] snd_timer_new.__key+0x0/0x20 ... acquired at: mark_lock+0x223/0x350 kernel/locking/lockdep.c:4678 __lock_acquire+0x116e/0x1fd0 kernel/locking/lockdep.c:5091 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 snd_timer_close+0xae/0x130 sound/core/timer.c:464 snd_seq_timer_close+0xa9/0xe0 sound/core/seq/seq_timer.c:302 queue_delete sound/core/seq/seq_queue.c:126 [inline] snd_seq_queue_delete+0x8f/0xf0 sound/core/seq/seq_queue.c:188 delete_seq_queue sound/core/seq/oss/seq_oss_init.c:371 [inline] snd_seq_oss_release+0x1d3/0x310 sound/core/seq/oss/seq_oss_init.c:416 odev_release+0x56/0x80 sound/core/seq/oss/seq_oss.c:144 __fput+0x429/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa1b/0x27e0 kernel/exit.c:878 do_group_exit+0x207/0x2c0 kernel/exit.c:1027 get_signal+0x176e/0x1850 kernel/signal.c:2907 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0xc9/0x360 kernel/entry/common.c:212 __do_fast_syscall_32+0xd0/0x120 arch/x86/entry/common.c:324 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 stack backtrace: CPU: 1 PID: 5363 Comm: syz-executor.1 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 mark_lock_irq+0x867/0xc20 kernel/locking/lockdep.c:4236 mark_lock+0x223/0x350 kernel/locking/lockdep.c:4678 __lock_acquire+0x116e/0x1fd0 kernel/locking/lockdep.c:5091 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] class_spinlock_constructor include/linux/spinlock.h:561 [inline] snd_timer_close_locked+0x53/0x8d0 sound/core/timer.c:412 snd_timer_close+0xae/0x130 sound/core/timer.c:464 snd_seq_timer_close+0xa9/0xe0 sound/core/seq/seq_timer.c:302 queue_delete sound/core/seq/seq_queue.c:126 [inline] snd_seq_queue_delete+0x8f/0xf0 sound/core/seq/seq_queue.c:188 delete_seq_queue sound/core/seq/oss/seq_oss_init.c:371 [inline] snd_seq_oss_release+0x1d3/0x310 sound/core/seq/oss/seq_oss_init.c:416 odev_release+0x56/0x80 sound/core/seq/oss/seq_oss.c:144 __fput+0x429/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa1b/0x27e0 kernel/exit.c:878 do_group_exit+0x207/0x2c0 kernel/exit.c:1027 get_signal+0x176e/0x1850 kernel/signal.c:2907 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:105 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:201 [inline] syscall_exit_to_user_mode+0xc9/0x360 kernel/entry/common.c:212 __do_fast_syscall_32+0xd0/0x120 arch/x86/entry/common.c:324 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:346 entry_SYSENTER_compat_after_hwframe+0x7a/0x84 RIP: 0023:0xf7299579 Code: Unable to access opcode bytes at 0xf729954f. RSP: 002b:00000000f5e8b66c EFLAGS: 00000206 ORIG_RAX: 00000000000000f0 RAX: 0000000000000001 RBX: 00000000f7415fcc RCX: 0000000000000081 RDX: 00000000000f4240 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00000000f72b5079 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000