------------[ cut here ]------------ ODEBUG: free active (active state 0) object: ffff88823bcc6090 object type: timer_list hint: rose_t0timer_expiry+0x0/0x350 WARNING: CPU: 0 PID: 7526 at lib/debugobjects.c:518 debug_print_object lib/debugobjects.c:515 [inline] WARNING: CPU: 0 PID: 7526 at lib/debugobjects.c:518 __debug_check_no_obj_freed lib/debugobjects.c:990 [inline] WARNING: CPU: 0 PID: 7526 at lib/debugobjects.c:518 debug_check_no_obj_freed+0x446/0x540 lib/debugobjects.c:1020 Modules linked in: CPU: 0 PID: 7526 Comm: syz.6.248 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 RIP: 0010:debug_print_object lib/debugobjects.c:515 [inline] RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:990 [inline] RIP: 0010:debug_check_no_obj_freed+0x446/0x540 lib/debugobjects.c:1020 Code: 4c 8b 4d 00 48 c7 c7 60 99 1c 8b 48 c7 c6 c0 95 1c 8b 48 c7 c2 e0 9a 1c 8b 8b 0c 24 4d 89 f8 41 55 e8 3e 85 1f fd 48 83 c4 08 <0f> 0b 4c 8b 6c 24 18 48 b9 00 00 00 00 00 fc ff df ff 05 33 fb 59 RSP: 0018:ffffc90000007a50 EFLAGS: 00010296 RAX: a24d90ae707c2c00 RBX: ffffffff97583850 RCX: ffff888028dc8000 RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002 RBP: ffffffff8accac60 R08: ffffc90000007647 R09: 1ffff92000000ec8 R10: dffffc0000000000 R11: fffff52000000ec9 R12: ffff88823bcc6200 R13: ffffffff897b1220 R14: ffff88823bcc6000 R15: ffff88823bcc6090 FS: 00007f10b7f0f6c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b32104ff8 CR3: 0000000063743000 CR4: 00000000003506f0 Call Trace: slab_free_hook mm/slub.c:1786 [inline] slab_free_freelist_hook+0x64/0x1a0 mm/slub.c:1824 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1e0 mm/slub.c:3843 rose_neigh_put include/net/rose.h:166 [inline] rose_timer_expiry+0x4c6/0x5f0 net/rose/rose_timer.c:183 call_timer_fn+0x189/0x540 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x542/0x800 kernel/time/timer.c:2023 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:lock_acquire+0x208/0x420 kernel/locking/lockdep.c:5758 Code: f7 84 24 80 00 00 00 00 02 00 00 43 c6 44 3c 04 f8 0f 85 f0 00 00 00 41 f7 c6 00 02 00 00 74 01 fb 48 c7 44 24 60 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 43 c7 44 3c 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc90003526e00 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 0000000000000000 RCX: a24d90ae707c2c00 RDX: 0000000000000000 RSI: ffffffff8acadb60 RDI: ffffffff8b1c8fa0 RBP: ffffc90003526f08 R08: dffffc0000000000 R09: 1ffffffff2238ca0 R10: dffffc0000000000 R11: fffffbfff2238ca1 R12: 1ffff920006a4dcc R13: ffffffff8d1320e0 R14: 0000000000000246 R15: dffffc0000000000 rcu_lock_acquire include/linux/rcupdate.h:334 [inline] rcu_read_lock include/linux/rcupdate.h:786 [inline] filemap_get_entry+0xea/0x3f0 mm/filemap.c:1849 shmem_get_folio_gfp+0x2a5/0x2aa0 mm/shmem.c:1975 shmem_get_folio mm/shmem.c:2164 [inline] shmem_write_begin+0xf2/0x420 mm/shmem.c:2706 generic_perform_write+0x2fe/0x5c0 mm/filemap.c:4036 shmem_file_write_iter+0xfb/0x120 mm/shmem.c:2883 __kernel_write_iter+0x28c/0x690 fs/read_write.c:517 dump_emit_page fs/coredump.c:957 [inline] dump_user_range+0x420/0x860 fs/coredump.c:984 elf_core_dump+0x31d0/0x3770 fs/binfmt_elf.c:2184 do_coredump+0x17cc/0x24d0 fs/coredump.c:833 get_signal+0x1133/0x13f0 kernel/signal.c:2888 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 irqentry_exit_to_user_mode+0x9/0x30 kernel/entry/common.c:315 exc_page_fault+0x8c/0x100 arch/x86/mm/fault.c:1519 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f10b6f9cde1 Code: 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 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f RSP: 002b:fffffffffffffe70 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f10b7216090 RCX: 00007f10b6f9cdd9 RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000 RBP: 00007f10b7032d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f10b7216128 R14: 00007f10b7216090 R15: 00007ffc6cfb98c8 ---------------- Code disassembly (best guess): 0: f7 84 24 80 00 00 00 testl $0x200,0x80(%rsp) 7: 00 02 00 00 b: 43 c6 44 3c 04 f8 movb $0xf8,0x4(%r12,%r15,1) 11: 0f 85 f0 00 00 00 jne 0x107 17: 41 f7 c6 00 02 00 00 test $0x200,%r14d 1e: 74 01 je 0x21 20: fb sti 21: 48 c7 44 24 60 0e 36 movq $0x45e0360e,0x60(%rsp) 28: e0 45 * 2a: 4b c7 04 3c 00 00 00 movq $0x0,(%r12,%r15,1) <-- trapping instruction 31: 00 32: 43 c7 44 3c 08 00 00 movl $0x0,0x8(%r12,%r15,1) 39: 00 00 3b: 65 gs 3c: 48 rex.W 3d: 8b .byte 0x8b 3e: 04 25 add $0x25,%al