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ODEBUG: free active (active state 0) object: ffff888053db0c90 object type: timer_list hint: rose_t0timer_expiry+0x0/0x150 include/linux/skbuff.h:2927
WARNING: lib/debugobjects.c:612 at debug_print_object+0x18e/0x2a0 lib/debugobjects.c:612, CPU#0: syz.5.2546/16544
Modules linked in:
CPU: 0 UID: 0 PID: 16544 Comm: syz.5.2546 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
RIP: 0010:debug_print_object+0x19b/0x2a0 lib/debugobjects.c:612
Code: b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 4f 48 8d 3d a2 01 df 0b 41 56 48 8b 14 dd e0 c7 f2 8b 4c 89 e6 <67> 48 0f b9 3a 58 83 05 7c 8a d5 0b 01 48 83 c4 18 5b 5d 41 5c 41
RSP: 0018:ffffc90000007a08 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: ffffffff8bf2c720 RSI: ffffffff8bf2c300 RDI: ffffffff90929b70
RBP: 0000000000000001 R08: ffff888053db0c90 R09: ffffffff8b906c80
R10: ffffffff9088f3d7 R11: ffff88802703e6b0 R12: ffffffff8bf2c300
R13: ffffffff8b906cc0 R14: ffffffff8a6243a0 R15: ffffc90000007b08
FS:  00007f25a4bf66c0(0000) GS:ffff8881248f3000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f24a811eeb8 CR3: 00000000825df000 CR4: 0000000000350ef0
Call Trace:
 <IRQ>
 __debug_check_no_obj_freed lib/debugobjects.c:1099 [inline]
 debug_check_no_obj_freed+0x4b7/0x600 lib/debugobjects.c:1129
 slab_free_hook mm/slub.c:2471 [inline]
 slab_free mm/slub.c:6670 [inline]
 kfree+0x2d1/0x6e0 mm/slub.c:6878
 rose_neigh_put include/net/rose.h:166 [inline]
 rose_timer_expiry+0x53f/0x630 net/rose/rose_timer.c:183
 call_timer_fn+0x19a/0x5a0 kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1799 [inline]
 __run_timers+0x74a/0xae0 kernel/time/timer.c:2373
 __run_timer_base kernel/time/timer.c:2385 [inline]
 __run_timer_base kernel/time/timer.c:2377 [inline]
 run_timer_base+0x114/0x190 kernel/time/timer.c:2394
 run_timer_softirq+0x1a/0x40 kernel/time/timer.c:2404
 handle_softirqs+0x219/0x950 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x109/0x170 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+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70 kernel/kcov.c:210
Code: a6 71 57 00 48 89 df 5b e9 ed 23 5d 00 be 03 00 00 00 5b e9 32 9f ec 02 66 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 34 24 65 48 8b 15 38 f7 f3 11 65 8b 05 49 f7 f3
RSP: 0018:ffffc90013776ab0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8201e768
RDX: ffff88802703db80 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000001e87 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: ffff88802703e6b0 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000001e87 R15: ffffea0000e35780
 shmem_add_to_page_cache+0x1d3/0xa70 mm/shmem.c:885
 shmem_alloc_and_add_folio+0x662/0xc20 mm/shmem.c:1958
 shmem_get_folio_gfp+0x67f/0x1610 mm/shmem.c:2556
 shmem_get_folio mm/shmem.c:2662 [inline]
 shmem_write_begin+0x1a4/0x3b0 mm/shmem.c:3315
 generic_perform_write+0x3c4/0x900 mm/filemap.c:4314
 shmem_file_write_iter+0x10e/0x140 mm/shmem.c:3490
 __kernel_write_iter+0x31a/0xb10 fs/read_write.c:619
 dump_emit_page fs/coredump.c:1298 [inline]
 dump_user_range+0x413/0xb70 fs/coredump.c:1372
 elf_core_dump+0x29c3/0x3c10 fs/binfmt_elf.c:2111
 coredump_write fs/coredump.c:1049 [inline]
 do_coredump fs/coredump.c:1126 [inline]
 vfs_coredump+0x2b85/0x55e0 fs/coredump.c:1200
 get_signal+0x22e1/0x26d0 kernel/signal.c:3019
 arch_do_signal_or_restart+0x8f/0x7e0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:75 [inline]
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 irqentry_exit_to_user_mode_prepare include/linux/irq-entry-common.h:270 [inline]
 irqentry_exit_to_user_mode include/linux/irq-entry-common.h:339 [inline]
 irqentry_exit+0x38a/0x8c0 kernel/entry/common.c:196
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:618
RIP: 0033:0x7f25a698f751
Code: 00 00 00 00 00 0f 1f 40 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 a8 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: 00007f25a6be6090 RCX: 00007f25a698f749
RDX: 0000000000000000 RSI: fffffffffffffe70 RDI: 0000000000008000
RBP: 00007f25a6a13f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000
R13: 00007f25a6be6128 R14: 00007f25a6be6090 R15: 00007ffec7bff248
 </TASK>
----------------
Code disassembly (best guess):
   0:	b8 00 00 00 00       	mov    $0x0,%eax
   5:	00 fc                	add    %bh,%ah
   7:	ff                   	(bad)
   8:	df 48 89             	fisttps -0x77(%rax)
   b:	fa                   	cli
   c:	48 c1 ea 03          	shr    $0x3,%rdx
  10:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
  14:	75 4f                	jne    0x65
  16:	48 8d 3d a2 01 df 0b 	lea    0xbdf01a2(%rip),%rdi        # 0xbdf01bf
  1d:	41 56                	push   %r14
  1f:	48 8b 14 dd e0 c7 f2 	mov    -0x740d3820(,%rbx,8),%rdx
  26:	8b
  27:	4c 89 e6             	mov    %r12,%rsi
* 2a:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2f:	58                   	pop    %rax
  30:	83 05 7c 8a d5 0b 01 	addl   $0x1,0xbd58a7c(%rip)        # 0xbd58ab3
  37:	48 83 c4 18          	add    $0x18,%rsp
  3b:	5b                   	pop    %rbx
  3c:	5d                   	pop    %rbp
  3d:	41 5c                	pop    %r12
  3f:	41                   	rex.B