syzbot

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ODEBUG: free active (active state 0) object: ffff888053d53490 object type: timer_list hint: rose_t0timer_expiry+0x0/0x350
WARNING: CPU: 1 PID: 5998 at lib/debugobjects.c:518 debug_print_object lib/debugobjects.c:515 [inline]
WARNING: CPU: 1 PID: 5998 at lib/debugobjects.c:518 __debug_check_no_obj_freed lib/debugobjects.c:990 [inline]
WARNING: CPU: 1 PID: 5998 at lib/debugobjects.c:518 debug_check_no_obj_freed+0x446/0x540 lib/debugobjects.c:1020
Modules linked in:
CPU: 1 PID: 5998 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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 8f 1c 8b 48 c7 c6 c0 8b 1c 8b 48 c7 c2 e0 90 1c 8b 8b 0c 24 4d 89 f8 41 55 e8 5e fe 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 73 4b 5a
RSP: 0018:ffffc900001f0a50 EFLAGS: 00010296
RAX: 08ac2e815fda1900 RBX: ffffffff97556128 RCX: ffff888022ae1e00
RDX: 0000000000000100 RSI: 0000000000000000 RDI: 0000000000000002
RBP: ffffffff8accab80 R08: ffff8880b8f28c13 R09: 1ffff110171e5182
R10: dffffc0000000000 R11: ffffed10171e5183 R12: ffff888053d53600
R13: ffffffff8979eb80 R14: ffff888053d53000 R15: ffff888053d53490
FS:  000055556e801500(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffe3c647f80 CR3: 000000006a84c000 CR4: 00000000003526e0
Call Trace:
 <IRQ>
 slab_free_hook mm/slub.c:1786 [inline]
 slab_free_freelist_hook+0xd2/0x1a0 mm/slub.c:1837
 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
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:console_flush_all+0x8b1/0xd20 arch/x86/include/asm/irqflags.h:-1
Code: ed 01 00 00 e8 f0 83 1b 00 4d 85 ff 48 8b 5c 24 38 75 07 e8 e1 83 1b 00 eb 06 e8 da 83 1b 00 fb 49 bf 00 00 00 00 00 fc ff df <48> 8b 44 24 58 42 0f b6 04 38 84 c0 0f 85 2f 02 00 00 80 3b 01 0f
RSP: 0018:ffffc900052d7700 EFLAGS: 00000293
RAX: ffffffff816b9886 RBX: ffffc900052d789f RCX: ffff888022ae1e00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc900052d7870 R08: ffffffff911c1507 R09: 1ffffffff22382a0
R10: dffffc0000000000 R11: fffffbfff22382a1 R12: ffffffff8d8b8220
R13: 1ffffffff19f96fc R14: ffffffff8d8b8278 R15: dffffc0000000000
 console_unlock+0xad/0x350 kernel/printk/printk.c:3069
 vprintk_emit+0x497/0x610 kernel/printk/printk.c:2341
 _printk+0xde/0x130 kernel/printk/printk.c:2366
 __ext4_msg+0x2b6/0x2c0 fs/ext4/super.c:1007
 ext4_put_super+0xb6/0xa40 fs/ext4/super.c:1312
 generic_shutdown_super+0x134/0x2b0 fs/super.c:693
 kill_block_super+0x44/0x90 fs/super.c:1660
 ext4_kill_sb+0x68/0xa0 fs/ext4/super.c:7407
 deactivate_locked_super+0x97/0x100 fs/super.c:481
 cleanup_mnt+0x43b/0x4d0 fs/namespace.c:1259
 task_work_run+0x1d4/0x260 kernel/task_work.c:245
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302
 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f069c59d9d7
Code: a2 c7 05 1c fd 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffe3c6485d8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f069c632050 RCX: 00007f069c59d9d7
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3c648690
RBP: 00007ffe3c648690 R08: 00007ffe3c649690 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3c649720
R13: 00007f069c632050 R14: 0000000000049ad1 R15: 00007ffe3c649760
 </TASK>
----------------
Code disassembly (best guess):
   0:	ed                   	in     (%dx),%eax
   1:	01 00                	add    %eax,(%rax)
   3:	00 e8                	add    %ch,%al
   5:	f0 83 1b 00          	lock sbbl $0x0,(%rbx)
   9:	4d 85 ff             	test   %r15,%r15
   c:	48 8b 5c 24 38       	mov    0x38(%rsp),%rbx
  11:	75 07                	jne    0x1a
  13:	e8 e1 83 1b 00       	call   0x1b83f9
  18:	eb 06                	jmp    0x20
  1a:	e8 da 83 1b 00       	call   0x1b83f9
  1f:	fb                   	sti
  20:	49 bf 00 00 00 00 00 	movabs $0xdffffc0000000000,%r15
  27:	fc ff df
* 2a:	48 8b 44 24 58       	mov    0x58(%rsp),%rax <-- trapping instruction
  2f:	42 0f b6 04 38       	movzbl (%rax,%r15,1),%eax
  34:	84 c0                	test   %al,%al
  36:	0f 85 2f 02 00 00    	jne    0x26b
  3c:	80 3b 01             	cmpb   $0x1,(%rbx)
  3f:	0f                   	.byte 0xf