------------[ cut here ]------------
ODEBUG: free active (active state 0) object type: timer_list hint: batadv_dat_purge+0x0/0x490
WARNING: CPU: 0 PID: 8528 at lib/debugobjects.c:512 debug_print_object lib/debugobjects.c:509 [inline]
WARNING: CPU: 0 PID: 8528 at lib/debugobjects.c:512 __debug_check_no_obj_freed lib/debugobjects.c:996 [inline]
WARNING: CPU: 0 PID: 8528 at lib/debugobjects.c:512 debug_check_no_obj_freed+0x451/0x610 lib/debugobjects.c:1027
Modules linked in:
CPU: 0 PID: 8528 Comm: kworker/u4:6 Not tainted 6.1.22-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Workqueue: netns cleanup_net
RIP: 0010:debug_print_object lib/debugobjects.c:509 [inline]
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:996 [inline]
RIP: 0010:debug_check_no_obj_freed+0x451/0x610 lib/debugobjects.c:1027
Code: 74 08 48 89 ef e8 3f aa a7 fd 48 8b 13 4c 8b 45 00 48 c7 c7 c0 c0 3c 8b 48 c7 c6 80 bd 3c 8b 44 89 f1 4d 89 f9 e8 ff 22 1a fd <0f> 0b 48 ba 00 00 00 00 00 fc ff df 4c 8b 74 24 38 ff 05 54 9d 1a
RSP: 0018:ffffc900039cf7e8 EFLAGS: 00010246
RAX: cfa0ee2aaa202900 RBX: ffffffff8b3cc138 RCX: ffff888025be9d40
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffffff8aed9c20 R08: ffffffff8152292e R09: fffff52000739e75
R10: 0000000000000000 R11: dffffc0000000001 R12: ffffffff8aed9c20
R13: ffff8880220bddb0 R14: 0000000000000000 R15: ffffffff8a4cdea0
FS:  0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f992c5511c0 CR3: 0000000026fbc000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600
Call Trace:
 <TASK>
 slab_free_hook mm/slub.c:1699 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 __kmem_cache_free+0x205/0x3c0 mm/slub.c:3674
 device_release+0x91/0x1c0
 kobject_cleanup lib/kobject.c:681 [inline]
 kobject_release lib/kobject.c:712 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x224/0x460 lib/kobject.c:729
 netdev_run_todo+0xe56/0xf40 net/core/dev.c:10372
 default_device_exit_batch+0x5c1/0x630 net/core/dev.c:11336
 ops_exit_list net/core/net_namespace.c:174 [inline]
 cleanup_net+0x763/0xb60 net/core/net_namespace.c:601
 process_one_work+0x8aa/0x11f0 kernel/workqueue.c:2289
 worker_thread+0xa5f/0x1210 kernel/workqueue.c:2436
 kthread+0x268/0x300 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306
 </TASK>