------------[ cut here ]------------ ODEBUG: free active (active state 0) object: ffff888099a56890 object type: timer_list hint: rose_t0timer_expiry+0x0/0x560 net/rose/rose_link.c:-1 WARNING: lib/debugobjects.c:632 at debug_print_object lib/debugobjects.c:629 [inline], CPU#0: syz.3.11861/21842 WARNING: lib/debugobjects.c:632 at __debug_check_no_obj_freed lib/debugobjects.c:1116 [inline], CPU#0: syz.3.11861/21842 WARNING: lib/debugobjects.c:632 at debug_check_no_obj_freed+0x405/0x550 lib/debugobjects.c:1146, CPU#0: syz.3.11861/21842 Modules linked in: CPU: 0 UID: 0 PID: 21842 Comm: syz.3.11861 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:debug_print_object lib/debugobjects.c:629 [inline] RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:1116 [inline] RIP: 0010:debug_check_no_obj_freed+0x44a/0x550 lib/debugobjects.c:1146 Code: 89 44 24 20 e8 f7 bf 74 fd 48 8b 44 24 20 4c 8b 4d 00 4c 89 ef 48 c7 c6 a0 a5 28 8c 48 c7 c2 20 ab 28 8c 8b 0c 24 4d 89 f8 50 <67> 48 0f b9 3a 48 83 c4 08 4c 8b 6c 24 18 48 b9 00 00 00 00 00 fc RSP: 0018:ffffc90000007b48 EFLAGS: 00010246 RAX: ffffffff8a9f6db0 RBX: ffffffff9a7aa040 RCX: 0000000000000000 RDX: ffffffff8c28ab20 RSI: ffffffff8c28a5a0 RDI: ffffffff903e6a40 RBP: ffffffff8bcf39a0 R08: ffff888099a56890 R09: ffffffff8bcf4d00 R10: dffffc0000000000 R11: ffffffff81b236d0 R12: ffff888099a56a00 R13: ffffffff903e6a40 R14: ffff888099a56000 R15: ffff888099a56890 FS: 0000555585cd3500(0000) GS:ffff888125213000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa9f29e7000 CR3: 000000008a758000 CR4: 00000000003526f0 Call Trace: slab_free_hook mm/slub.c:2620 [inline] slab_free mm/slub.c:6246 [inline] kfree+0x13e/0x640 mm/slub.c:6561 rose_neigh_put include/net/rose.h:166 [inline] rose_timer_expiry+0x4cb/0x600 net/rose/rose_timer.c:183 call_timer_fn+0x192/0x5e0 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers kernel/time/timer.c:2374 [inline] __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2386 run_timer_base kernel/time/timer.c:2395 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2405 handle_softirqs+0x22a/0x840 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:preempt_schedule_irq+0x48/0xa0 kernel/sched/core.c:7512 Code: 49 be 00 00 00 00 00 fc ff df eb 09 48 f7 03 10 00 00 00 74 53 bf 01 00 00 00 e8 33 d9 d9 f5 e8 6e e3 13 f6 fb bf 01 00 00 00 13 a3 ff ff 9c 58 fa a9 00 02 00 00 74 05 e8 34 e5 13 f6 bf 01 RSP: 0018:ffffc9000d82f860 EFLAGS: 00000202 RAX: 0000000000000f0b RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000006 RSI: ffffffff8dfd8f45 RDI: 0000000000000001 RBP: 0000000000000000 R08: ffffffff903386f7 R09: 1ffffffff20670de R10: dffffc0000000000 R11: fffffbfff20670df R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000 irqentry_exit_to_kernel_mode include/linux/irq-entry-common.h:547 [inline] irqentry_exit+0x14f/0x730 kernel/entry/common.c:164 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:lockdep_unregister_key+0x2d5/0x350 kernel/locking/lockdep.c:6616 Code: 11 0a 09 00 89 c6 48 c7 c7 30 28 49 96 e8 63 93 19 0a 90 e9 65 fe ff ff e8 e8 d4 16 0a 41 f7 c7 00 02 00 00 74 b3 fb 40 84 ed <75> b2 eb c3 90 0f 0b 90 e9 26 ff ff ff 90 0f 0b 90 e9 2e ff ff ff RSP: 0018:ffffc9000d82f980 EFLAGS: 00000202 RAX: 0000000000000046 RBX: 0000000000000001 RCX: 0000000000000046 RDX: ffffffff9404a398 RSI: ffffffff8dff28c3 RDI: ffffffff8c289f60 RBP: ffff88803e609e01 R08: ffffffff81af4528 R09: ffffffff8e95cce0 R10: dffffc0000000000 R11: fffffbfff20670df R12: 0000000000000000 R13: ffff88806966f269 R14: 0000000000001000 R15: 0000000000000a87 qdisc_lock_uninit include/net/pkt_sched.h:332 [inline] __qdisc_destroy+0x1ab/0x470 net/sched/sch_generic.c:1102 qdisc_put net/sched/sch_generic.c:1128 [inline] dev_shutdown+0x34c/0x440 net/sched/sch_generic.c:1493 unregister_netdevice_many_notify+0x11b2/0x22c0 net/core/dev.c:12413 unregister_netdevice_many net/core/dev.c:12488 [inline] unregister_netdevice_queue+0x31f/0x360 net/core/dev.c:12298 unregister_netdevice include/linux/netdevice.h:3447 [inline] __tun_detach+0x6d9/0x15d0 drivers/net/tun.c:621 tun_detach drivers/net/tun.c:637 [inline] tun_chr_close+0x10a/0x1c0 drivers/net/tun.c:3438 __fput+0x44f/0xa60 fs/file_table.c:510 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f620b39cdd9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd748784b8 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4 RAX: 0000000000000000 RBX: 00007ffd748785a0 RCX: 00007f620b39cdd9 RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003 RBP: 00000000001605e9 R08: 0000000000000001 R09: 0000000000000000 R10: 0000001b33d20000 R11: 0000000000000246 R12: 00007ffd748785e0 R13: 00007f620b615fac R14: 000000000016068f R15: 00007f620b615fa0 ---------------- Code disassembly (best guess): 0: 89 44 24 20 mov %eax,0x20(%rsp) 4: e8 f7 bf 74 fd call 0xfd74c000 9: 48 8b 44 24 20 mov 0x20(%rsp),%rax e: 4c 8b 4d 00 mov 0x0(%rbp),%r9 12: 4c 89 ef mov %r13,%rdi 15: 48 c7 c6 a0 a5 28 8c mov $0xffffffff8c28a5a0,%rsi 1c: 48 c7 c2 20 ab 28 8c mov $0xffffffff8c28ab20,%rdx 23: 8b 0c 24 mov (%rsp),%ecx 26: 4d 89 f8 mov %r15,%r8 29: 50 push %rax * 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction 2f: 48 83 c4 08 add $0x8,%rsp 33: 4c 8b 6c 24 18 mov 0x18(%rsp),%r13 38: 48 rex.W 39: b9 00 00 00 00 mov $0x0,%ecx 3e: 00 fc add %bh,%ah