==================================================================
BUG: KASAN: use-after-free in device_for_each_child+0x17a/0x190 drivers/base/core.c:4044
Read of size 8 at addr ffff8880648ed5f8 by task kbnepd bnep0/5728

CPU: 1 PID: 5728 Comm: kbnepd bnep0 Not tainted 6.9.0-rc6-syzkaller-00053-g0106679839f7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:114
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 device_for_each_child+0x17a/0x190 drivers/base/core.c:4044
 pm_runtime_set_memalloc_noio+0xf2/0x180 drivers/base/power/runtime.c:248
 netdev_unregister_kobject+0x1ed/0x270 net/core/net-sysfs.c:2106
 unregister_netdevice_many_notify+0xc8a/0x19f0 net/core/dev.c:11135
 unregister_netdevice_many net/core/dev.c:11163 [inline]
 unregister_netdevice_queue+0x307/0x3f0 net/core/dev.c:11042
 unregister_netdevice include/linux/netdevice.h:3115 [inline]
 unregister_netdev+0x1c/0x30 net/core/dev.c:11181
 bnep_session+0x220d/0x2d60 net/bluetooth/bnep/core.c:525
 kthread+0x2c1/0x3a0 kernel/kthread.c:388
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x400000000 pfn:0x648ed
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000400000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x102000(__GFP_NOWARN|__GFP_HARDWALL), pid 7548, tgid 1562395361 (syz-executor.4), ts 7548, free_ts 229195728304
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d4/0x350 mm/page_alloc.c:1534
 prep_new_page mm/page_alloc.c:1541 [inline]
 get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3317
 __alloc_pages+0x22b/0x2460 mm/page_alloc.c:4575
 alloc_pages_mpol+0x275/0x610 mm/mempolicy.c:2264
 stack_depot_save_flags+0x566/0x8f0 lib/stackdepot.c:635
 kasan_save_stack+0x42/0x60 mm/kasan/common.c:48
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
 poison_slab_object mm/kasan/common.c:240 [inline]
 __kasan_slab_free+0x11d/0x1a0 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2106 [inline]
 slab_free mm/slub.c:4280 [inline]
 kfree+0x129/0x390 mm/slub.c:4390
 free_irq_routing_table.part.0+0x16a/0x250 arch/x86/kvm/../../../virt/kvm/irqchip.c:112
 free_irq_routing_table arch/x86/kvm/../../../virt/kvm/irqchip.c:103 [inline]
 kvm_free_irq_routing+0x44/0xb0 arch/x86/kvm/../../../virt/kvm/irqchip.c:124
 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:1352 [inline]
 kvm_put_kvm+0x25c/0xb80 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1419
 kvm_vcpu_release+0x51/0x70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4187
 __fput+0x270/0xb80 fs/file_table.c:422
 __fput_sync+0x47/0x50 fs/file_table.c:507
page last free pid 7548 tgid 7548 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1141 [inline]
 free_unref_page_prepare+0x527/0xb10 mm/page_alloc.c:2347
 free_unref_page+0x33/0x3c0 mm/page_alloc.c:2487
 stack_depot_save_flags+0x2da/0x8f0 lib/stackdepot.c:673
 kasan_save_stack+0x42/0x60 mm/kasan/common.c:48
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
 poison_slab_object mm/kasan/common.c:240 [inline]
 __kasan_slab_free+0x11d/0x1a0 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2106 [inline]
 slab_free mm/slub.c:4280 [inline]
 kfree+0x129/0x390 mm/slub.c:4390
 free_irq_routing_table.part.0+0x16a/0x250 arch/x86/kvm/../../../virt/kvm/irqchip.c:112
 free_irq_routing_table arch/x86/kvm/../../../virt/kvm/irqchip.c:103 [inline]
 kvm_free_irq_routing+0x44/0xb0 arch/x86/kvm/../../../virt/kvm/irqchip.c:124
 kvm_destroy_vm arch/x86/kvm/../../../virt/kvm/kvm_main.c:1352 [inline]
 kvm_put_kvm+0x25c/0xb80 arch/x86/kvm/../../../virt/kvm/kvm_main.c:1419
 kvm_vcpu_release+0x51/0x70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:4187
 __fput+0x270/0xb80 fs/file_table.c:422
 __fput_sync+0x47/0x50 fs/file_table.c:507
 __do_sys_close fs/open.c:1556 [inline]
 __se_sys_close fs/open.c:1541 [inline]
 __x64_sys_close+0x86/0x100 fs/open.c:1541
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcf/0x260 arch/x86/entry/common.c:83

Memory state around the buggy address:
 ffff8880648ed480: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8880648ed500: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff8880648ed580: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                                                ^
 ffff8880648ed600: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff8880648ed680: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================