------------[ cut here ]------------ ODEBUG: free active (active state 0) object: ffff888058c3b090 object type: timer_list hint: rose_t0timer_expiry+0x0/0x350 net/rose/rose_link.c:-1 WARNING: CPU: 0 PID: 6522 at lib/debugobjects.c:615 debug_print_object lib/debugobjects.c:612 [inline] WARNING: CPU: 0 PID: 6522 at lib/debugobjects.c:615 __debug_check_no_obj_freed lib/debugobjects.c:1099 [inline] WARNING: CPU: 0 PID: 6522 at lib/debugobjects.c:615 debug_check_no_obj_freed+0x447/0x540 lib/debugobjects.c:1129 Modules linked in: CPU: 0 UID: 0 PID: 6522 Comm: kworker/0:2H Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: events_highpri snd_vmidi_output_work RIP: 0010:debug_print_object lib/debugobjects.c:612 [inline] RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:1099 [inline] RIP: 0010:debug_check_no_obj_freed+0x447/0x540 lib/debugobjects.c:1129 Code: 4c 8b 4d 00 48 c7 c7 80 72 7f 8b 48 c7 c6 00 6f 7f 8b 48 c7 c2 00 74 7f 8b 8b 0c 24 4d 89 f8 41 55 e8 bd cc f2 fc 48 83 c4 08 <0f> 0b 4c 8b 6c 24 18 48 b9 00 00 00 00 00 fc ff df ff 05 be 72 a6 RSP: 0018:ffffc90000007a70 EFLAGS: 00010292 RAX: a3dea998c9771200 RBX: ffffffff994d1550 RCX: ffff888024e99e40 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002 RBP: ffffffff8b2cfa80 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffffbfff1b3a128 R12: ffff888058c3b200 R13: ffffffff8a1170d0 R14: ffff888058c3b000 R15: ffff888058c3b090 FS: 0000000000000000(0000) GS:ffff888126676000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fd72d8d6d58 CR3: 00000000777a8000 CR4: 00000000003526f0 Call Trace: slab_free_hook mm/slub.c:2474 [inline] slab_free mm/slub.c:6642 [inline] kfree+0x10d/0x6b0 mm/slub.c:6849 rose_neigh_put include/net/rose.h:166 [inline] rose_timer_expiry+0x4c7/0x5f0 net/rose/rose_timer.c:183 call_timer_fn+0x17a/0x5d0 kernel/time/timer.c:1747 expire_timers kernel/time/timer.c:1798 [inline] __run_timers kernel/time/timer.c:2372 [inline] __run_timer_base+0x616/0x860 kernel/time/timer.c:2384 run_timer_base kernel/time/timer.c:2393 [inline] run_timer_softirq+0xb3/0x170 kernel/time/timer.c:2403 handle_softirqs+0x282/0x850 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xc6/0x1e0 kernel/softirq.c:723 irq_exit_rcu+0x5/0x20 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1052 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1052 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa4/0x100 kernel/locking/spinlock.c:194 Code: 74 05 e8 bf e9 af f6 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 b7 a7 78 f6 65 8b 05 e0 fe 03 07 85 c0 74 40 48 c7 04 24 0e 36 RSP: 0018:ffffc90003c2f880 EFLAGS: 00000206 RAX: a3dea998c9771200 RBX: 0000000000000a02 RCX: a3dea998c9771200 RDX: 0000000000000006 RSI: ffffffff8d2d0eab RDI: 0000000000000001 RBP: ffffc90003c2f918 R08: ffffffff8f35f977 R09: 1ffffffff1e6bf2e R10: dffffc0000000000 R11: fffffbfff1e6bf2f R12: dffffc0000000000 R13: ffff88802e494818 R14: ffff88802e494838 R15: 1ffff92000785f10 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] class_spinlock_irqsave_destructor include/linux/spinlock.h:585 [inline] snd_rawmidi_transmit+0xc5/0x100 sound/core/rawmidi.c:1493 snd_vmidi_output_work+0x19f/0x410 sound/core/seq/seq_virmidi.c:151 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xadd/0x1780 kernel/workqueue.c:3346 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3427 kthread+0x70d/0x890 kernel/kthread.c:463 ret_from_fork+0x4b4/0x840 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess): 0: 74 05 je 0x7 2: e8 bf e9 af f6 call 0xf6afe9c6 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 4f jne 0x6b 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 b7 a7 78 f6 call 0xf678a7e6 <-- trapping instruction 2f: 65 8b 05 e0 fe 03 07 mov %gs:0x703fee0(%rip),%eax # 0x703ff16 36: 85 c0 test %eax,%eax 38: 74 40 je 0x7a 3a: 48 rex.W 3b: c7 .byte 0xc7 3c: 04 24 add $0x24,%al 3e: 0e (bad) 3f: 36 ss