------------[ cut here ]------------ ODEBUG: free active (active state 0) object: ffff888028eb7278 object type: timer_list hint: br_ip6_multicast_port_query_expired+0x0/0x380 net/bridge/br_multicast.c:-1 WARNING: lib/debugobjects.c:632 at debug_print_object lib/debugobjects.c:629 [inline], CPU#0: kworker/0:10/15593 WARNING: lib/debugobjects.c:632 at __debug_check_no_obj_freed lib/debugobjects.c:1116 [inline], CPU#0: kworker/0:10/15593 WARNING: lib/debugobjects.c:632 at debug_check_no_obj_freed+0x405/0x550 lib/debugobjects.c:1146, CPU#0: kworker/0:10/15593 Modules linked in: CPU: 0 UID: 0 PID: 15593 Comm: kworker/0:10 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: mld mld_ifc_work 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 87 53 74 fd 48 8b 44 24 20 4c 8b 4d 00 4c 89 ef 48 c7 c6 a0 b2 28 8c 48 c7 c2 20 b8 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:ffffc90000007c70 EFLAGS: 00010246 RAX: ffffffff8a7dc380 RBX: ffffffff9a727348 RCX: 0000000000000000 RDX: ffffffff8c28b820 RSI: ffffffff8c28b2a0 RDI: ffffffff903b89e0 RBP: ffffffff8bcf3a20 R08: ffff888028eb7278 R09: ffffffff8bcf4d80 R10: dffffc0000000000 R11: ffffffff81b20950 R12: ffff888028eb7400 R13: ffffffff903b89e0 R14: ffff888028eb7000 R15: ffff888028eb7278 FS: 0000000000000000(0000) GS:ffff888125290000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000000c1000 CR3: 000000007eb00000 CR4: 00000000003526f0 Call Trace: slab_free_hook mm/slub.c:2620 [inline] slab_free mm/slub.c:6250 [inline] kfree+0x13e/0x640 mm/slub.c:6565 kobject_cleanup lib/kobject.c:689 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x228/0x560 lib/kobject.c:737 rcu_do_batch kernel/rcu/tree.c:2617 [inline] rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869 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:unwind_next_frame+0x843/0x2550 arch/x86/kernel/unwind_orc.c:530 Code: 48 89 d8 48 c1 e8 03 80 3c 28 00 74 08 48 89 df e8 d2 fd b9 00 48 8b 3b 48 85 ff 0f 84 4e 0e 00 00 48 83 c7 60 e9 aa 02 00 00 <83> fb 03 0f 84 65 01 00 00 83 fb 04 0f 85 d7 0c 00 00 49 8d 5e 40 RSP: 0018:ffffc90003647218 EFLAGS: 00000202 RAX: ffffc9000364731d RBX: 0000000000000004 RCX: ffffffff9052f5c4 RDX: ffffffff90d3a21e RSI: ffffffff90d3a222 RDI: ffffffff8c28ac00 RBP: dffffc0000000000 R08: 0000000000000001 R09: ffffffff8e95cd60 R10: ffffc90003647338 R11: ffffffff81b0d840 R12: ffffffff90d3a223 R13: 1ffff920006c8e5d R14: ffffc900036472e8 R15: ffffc90003647320 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122 save_stack+0x122/0x230 mm/page_owner.c:165 __reset_page_owner+0x71/0x1f0 mm/page_owner.c:320 reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1402 [inline] __free_frozen_pages+0xbc7/0xd30 mm/page_alloc.c:2943 __slab_free+0x274/0x2c0 mm/slub.c:5612 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4569 [inline] slab_alloc_node mm/slub.c:4898 [inline] kmem_cache_alloc_node_noprof+0x384/0x690 mm/slub.c:4950 __alloc_skb+0x1d0/0x7d0 net/core/skbuff.c:702 alloc_skb include/linux/skbuff.h:1383 [inline] mld_newpack+0x14c/0xc90 net/ipv6/mcast.c:1775 add_grhead+0x5a/0x2a0 net/ipv6/mcast.c:1886 add_grec+0x1452/0x1740 net/ipv6/mcast.c:2025 mld_send_cr net/ipv6/mcast.c:2148 [inline] mld_ifc_work+0x6e6/0xe70 net/ipv6/mcast.c:2693 process_one_work kernel/workqueue.c:3302 [inline] process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385 worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ---------------- Code disassembly (best guess): 0: 89 44 24 20 mov %eax,0x20(%rsp) 4: e8 87 53 74 fd call 0xfd745390 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 b2 28 8c mov $0xffffffff8c28b2a0,%rsi 1c: 48 c7 c2 20 b8 28 8c mov $0xffffffff8c28b820,%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