------------[ cut here ]------------ ODEBUG: free active (active state 0) object: ffff888025c20090 object type: timer_list hint: rose_t0timer_expiry+0x0/0x350 WARNING: CPU: 1 PID: 24 at lib/debugobjects.c:518 debug_print_object lib/debugobjects.c:515 [inline] WARNING: CPU: 1 PID: 24 at lib/debugobjects.c:518 __debug_check_no_obj_freed lib/debugobjects.c:990 [inline] WARNING: CPU: 1 PID: 24 at lib/debugobjects.c:518 debug_check_no_obj_freed+0x446/0x540 lib/debugobjects.c:1020 Modules linked in: CPU: 1 PID: 24 Comm: kworker/1:0H Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Workqueue: events_highpri snd_vmidi_output_work RIP: 0010:debug_print_object lib/debugobjects.c:515 [inline] RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:990 [inline] RIP: 0010:debug_check_no_obj_freed+0x446/0x540 lib/debugobjects.c:1020 Code: 4c 8b 4d 00 48 c7 c7 80 7c fc 8a 48 c7 c6 e0 78 fc 8a 48 c7 c2 00 7e fc 8a 8b 0c 24 4d 89 f8 41 55 e8 5e 27 2a fd 48 83 c4 08 <0f> 0b 4c 8b 6c 24 18 48 b9 00 00 00 00 00 fc ff df ff 05 f3 e4 24 RSP: 0018:ffffc900001f0a50 EFLAGS: 00010296 RAX: 7b2a8852d22a6f00 RBX: ffffffff9705dda0 RCX: ffff88801ca48000 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002 RBP: ffffffff8aaca000 R08: ffffc900001f0647 R09: 1ffff9200003e0c8 R10: dffffc0000000000 R11: fffff5200003e0c9 R12: ffff888025c20200 R13: ffffffff8966f5b0 R14: ffff888025c20000 R15: ffff888025c20090 FS: 0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000001000 CR3: 0000000060620000 CR4: 00000000003506e0 Call Trace: slab_free_hook mm/slub.c:1786 [inline] slab_free_freelist_hook+0xd2/0x1b0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3843 rose_neigh_put include/net/rose.h:166 [inline] rose_timer_expiry+0x4c6/0x5f0 net/rose/rose_timer.c:183 call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x52d/0x7d0 kernel/time/timer.c:2022 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa9/0x110 kernel/locking/spinlock.c:194 Code: 74 05 e8 fa 31 14 f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 e2 a9 e3 f6 65 8b 05 33 f8 8b 75 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc900001e7540 EFLAGS: 00000206 RAX: 7b2a8852d22a6f00 RBX: 0000000000000a02 RCX: 7b2a8852d22a6f00 RDX: dffffc0000000000 RSI: ffffffff8aaabca0 RDI: 0000000000000001 RBP: ffffc900001e75d0 R08: ffffffff90da7587 R09: 1ffffffff21b4eb0 R10: dffffc0000000000 R11: fffffbfff21b4eb1 R12: dffffc0000000000 R13: 1ffff11004acc041 R14: ffff888025660278 R15: 1ffff9200003cea8 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] snd_seq_oss_readq_put_event+0x16b/0x250 sound/core/seq/oss/seq_oss_readq.c:-1 snd_seq_oss_readq_puts+0xde/0x160 sound/core/seq/oss/seq_oss_readq.c:100 send_midi_event sound/core/seq/oss/seq_oss_midi.c:629 [inline] snd_seq_oss_midi_input+0x476/0x960 sound/core/seq/oss/seq_oss_midi.c:544 __snd_seq_deliver_single_event sound/core/seq/seq_clientmgr.c:655 [inline] snd_seq_deliver_single_event+0x5ac/0xb70 sound/core/seq/seq_clientmgr.c:718 __deliver_to_subscribers sound/core/seq/seq_clientmgr.c:773 [inline] deliver_to_subscribers sound/core/seq/seq_clientmgr.c:803 [inline] snd_seq_deliver_event+0x503/0x970 sound/core/seq/seq_clientmgr.c:853 snd_seq_kernel_client_dispatch+0x201/0x2f0 sound/core/seq/seq_clientmgr.c:2538 snd_vmidi_output_work+0x24f/0x410 sound/core/seq/seq_virmidi.c:157 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 ---------------- Code disassembly (best guess): 0: 74 05 je 0x7 2: e8 fa 31 14 f7 call 0xf7143201 7: 48 c7 44 24 20 00 00 movq $0x0,0x20(%rsp) e: 00 00 10: 9c pushf 11: 8f 44 24 20 pop 0x20(%rsp) 15: f6 44 24 21 02 testb $0x2,0x21(%rsp) 1a: 75 4b jne 0x67 1c: f7 c3 00 02 00 00 test $0x200,%ebx 22: 74 01 je 0x25 24: fb sti 25: bf 01 00 00 00 mov $0x1,%edi * 2a: e8 e2 a9 e3 f6 call 0xf6e3aa11 <-- trapping instruction 2f: 65 8b 05 33 f8 8b 75 mov %gs:0x758bf833(%rip),%eax # 0x758bf869 36: 85 c0 test %eax,%eax 38: 74 3c je 0x76 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: 04 24 add $0x24,%al 3e: 0e (bad) 3f: 36 ss