------------[ cut here ]------------ ODEBUG: free active (active state 0) object type: timer_list hint: rose_transmit_restart_request net/rose/rose_link.c:-1 [inline] ODEBUG: free active (active state 0) object type: timer_list hint: rose_t0timer_expiry+0x0/0x350 net/rose/rose_link.c:284 WARNING: CPU: 0 PID: 6707 at lib/debugobjects.c:518 debug_print_object lib/debugobjects.c:515 [inline] WARNING: CPU: 0 PID: 6707 at lib/debugobjects.c:518 __debug_check_no_obj_freed lib/debugobjects.c:979 [inline] WARNING: CPU: 0 PID: 6707 at lib/debugobjects.c:518 debug_check_no_obj_freed+0x43c/0x530 lib/debugobjects.c:1009 Modules linked in: CPU: 0 PID: 6707 Comm: kworker/0:2H Not tainted syzkaller #0 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:515 [inline] RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:979 [inline] RIP: 0010:debug_check_no_obj_freed+0x43c/0x530 lib/debugobjects.c:1009 Code: ef e8 a8 6a c5 fd 4c 8b 45 00 48 c7 c7 c0 00 df 8a 48 c7 c6 80 fd de 8a 48 c7 c2 20 02 df 8a 8b 0c 24 4d 89 e9 e8 64 60 41 fd <0f> 0b 4c 8b 6c 24 18 48 b9 00 00 00 00 00 fc ff df ff 05 95 04 14 RSP: 0018:ffffc90000007a10 EFLAGS: 00010246 RAX: 9fd1dbea65218f00 RBX: ffffffff96e7ca78 RCX: ffff888026013b80 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002 RBP: ffffffff8a8de2a0 R08: dffffc0000000000 R09: fffff52000000ed1 R10: fffff52000000ed1 R11: 1ffff92000000ed0 R12: ffff88805c4db600 R13: ffffffff891958b0 R14: ffff88805c4db000 R15: ffff88805c4db490 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000000b000 CR3: 000000005b54b000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: slab_free_hook mm/slub.c:1704 [inline] slab_free_freelist_hook+0xd2/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700 rose_neigh_put include/net/rose.h:166 [inline] rose_timer_expiry+0x4a7/0x5d0 net/rose/rose_timer.c:183 call_timer_fn+0x1a0/0x670 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x529/0x7d0 kernel/time/timer.c:2022 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:2035 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596 __do_softirq kernel/softirq.c:630 [inline] invoke_softirq kernel/softirq.c:470 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:679 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa5/0x100 kernel/locking/spinlock.c:194 Code: 74 05 e8 ce 48 65 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 f6 cd 35 f7 65 8b 05 77 85 e0 75 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc9000596fa80 EFLAGS: 00000206 RAX: 9fd1dbea65218f00 RBX: 0000000000000a06 RCX: 9fd1dbea65218f00 RDX: dffffc0000000000 RSI: ffffffff8a8c0580 RDI: 0000000000000001 RBP: ffffc9000596fb18 R08: dffffc0000000000 R09: fffffbfff215c46b R10: fffffbfff215c46b R11: 1ffffffff215c46a R12: dffffc0000000000 R13: ffff88802e663518 R14: ffff88802e663530 R15: 1ffff92000b2df50 spin_unlock_irqrestore include/linux/spinlock.h:406 [inline] snd_rawmidi_transmit+0x98/0xc0 sound/core/rawmidi.c:1478 snd_vmidi_output_work+0x1a0/0x400 sound/core/seq/seq_virmidi.c:151 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 ---------------- Code disassembly (best guess): 0: 74 05 je 0x7 2: e8 ce 48 65 f7 call 0xf76548d5 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 f6 cd 35 f7 call 0xf735ce25 <-- trapping instruction 2f: 65 8b 05 77 85 e0 75 mov %gs:0x75e08577(%rip),%eax # 0x75e085ad 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