------------[ cut here ]------------ ODEBUG: free active (active state 0) object: ffff888075410c90 object type: timer_list hint: rose_t0timer_expiry+0x0/0x560 net/rose/rose_link.c:-1 WARNING: lib/debugobjects.c:615 at debug_print_object lib/debugobjects.c:612 [inline], CPU#1: syz.4.5730/28468 WARNING: lib/debugobjects.c:615 at __debug_check_no_obj_freed lib/debugobjects.c:1099 [inline], CPU#1: syz.4.5730/28468 WARNING: lib/debugobjects.c:615 at debug_check_no_obj_freed+0x405/0x550 lib/debugobjects.c:1129, CPU#1: syz.4.5730/28468 Modules linked in: CPU: 1 UID: 0 PID: 28468 Comm: syz.4.5730 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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+0x44a/0x550 lib/debugobjects.c:1129 Code: 89 44 24 20 e8 b7 6b 7e fd 48 8b 44 24 20 4c 8b 4d 00 4c 89 ef 48 c7 c6 40 6b 27 8c 48 c7 c2 c0 70 27 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:ffffc90000a08b68 EFLAGS: 00010246 RAX: ffffffff8a888d00 RBX: ffffffff9a459710 RCX: 0000000000000000 RDX: ffffffff8c2770c0 RSI: ffffffff8c276b40 RDI: ffffffff901b4570 RBP: ffffffff8bcf4a00 R08: ffff888075410c90 R09: ffffffff8bcf5d20 R10: dffffc0000000000 R11: ffffffff81b099e0 R12: ffff888075410e00 R13: ffffffff901b4570 R14: ffff888075410000 R15: ffff888075410c90 FS: 00007f561c8766c0(0000) GS:ffff8881255b0000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff24e59e368 CR3: 000000005593c000 CR4: 00000000003526f0 Call Trace: slab_free_hook mm/slub.c:2601 [inline] slab_free mm/slub.c:6082 [inline] kfree+0x13a/0x610 mm/slub.c:6399 rose_neigh_put include/net/rose.h:166 [inline] rose_timer_expiry+0x4cb/0x600 net/rose/rose_timer.c:183 call_timer_fn+0x192/0x5a0 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers kernel/time/timer.c:2373 [inline] __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385 run_timer_base kernel/time/timer.c:2394 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404 handle_softirqs+0x22a/0x7c0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:lock_acquire+0x221/0x330 kernel/locking/lockdep.c:5872 Code: ff ff ff e8 a1 e5 fd 09 f7 44 24 08 00 02 00 00 0f 84 3a ff ff ff 65 48 8b 05 1b a3 76 11 48 3b 44 24 58 75 33 fb 48 83 c4 60 <5b> 41 5c 41 5d 41 5e 41 5f 5d e9 00 ca 00 0a cc 48 8d 3d c8 7f 73 RSP: 0018:ffffc9001054ecf8 EFLAGS: 00000282 RAX: 32ad7549c900f700 RBX: 0000000000000000 RCX: 0000000000000046 RDX: 00000000b0f12c24 RSI: ffffffff8e151802 RDI: ffffffff8c276500 RBP: ffffffff81759275 R08: ffffffff81759275 R09: ffffffff8e75e0a0 R10: ffffc9001054ee58 R11: ffffffff81af7870 R12: 0000000000000002 R13: ffffffff8e75e0a0 R14: 0000000000000000 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:312 [inline] rcu_read_lock include/linux/rcupdate.h:850 [inline] class_rcu_constructor include/linux/rcupdate.h:1193 [inline] unwind_next_frame+0xc2/0x23c0 arch/x86/kernel/unwind_orc.c:495 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 __set_page_owner+0x8d/0x4c0 mm/page_owner.c:341 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x228/0x280 mm/page_alloc.c:1884 prep_new_page mm/page_alloc.c:1892 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3950 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5245 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 folio_alloc_mpol_noprof+0x39/0x70 mm/mempolicy.c:2505 shmem_alloc_folio mm/shmem.c:1919 [inline] shmem_alloc_and_add_folio+0x445/0xf80 mm/shmem.c:1961 shmem_get_folio_gfp+0x5a9/0x1670 mm/shmem.c:2585 shmem_fault+0x179/0x390 mm/shmem.c:2786 __do_fault+0x138/0x390 mm/memory.c:5323 do_read_fault mm/memory.c:5758 [inline] do_fault mm/memory.c:5892 [inline] do_pte_missing+0x21a2/0x37a0 mm/memory.c:4404 handle_pte_fault mm/memory.c:6276 [inline] __handle_mm_fault mm/memory.c:6414 [inline] handle_mm_fault+0x1b8c/0x32a0 mm/memory.c:6583 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x165b/0x29d0 mm/gup.c:1428 populate_vma_page_range+0x2be/0x3c0 mm/gup.c:1860 __mm_populate+0x25f/0x390 mm/gup.c:1963 mm_populate include/linux/mm.h:3683 [inline] vm_mmap_pgoff+0x3aa/0x4f0 mm/util.c:586 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f561b99bf79 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:00007f561c876028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009 RAX: ffffffffffffffda RBX: 00007f561bc16090 RCX: 00007f561b99bf79 RDX: 0000000001000005 RSI: 0000000000b36000 RDI: 0000200000000000 RBP: 00007f561ba327e0 R08: ffffffffffffffff R09: 0000000000000000 R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f561bc16128 R14: 00007f561bc16090 R15: 00007fff940bef38 ---------------- Code disassembly (best guess): 0: 89 44 24 20 mov %eax,0x20(%rsp) 4: e8 b7 6b 7e fd call 0xfd7e6bc0 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 40 6b 27 8c mov $0xffffffff8c276b40,%rsi 1c: 48 c7 c2 c0 70 27 8c mov $0xffffffff8c2770c0,%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