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BUG: KASAN: use-after-free in kobject_put+0xcb/0xe0 lib/kobject.c:704
Read of size 1 at addr ffff88817f30dccc by task syz-executor3/11972

CPU: 1 PID: 11972 Comm: syz-executor3 Not tainted 4.20.0-rc3+ #347
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x244/0x39d lib/dump_stack.c:113
 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256
 kasan_report_error mm/kasan/report.c:354 [inline]
 kasan_report.cold.8+0x242/0x309 mm/kasan/report.c:412
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430
 kobject_put+0xcb/0xe0 lib/kobject.c:704
 put_device+0x20/0x30 drivers/base/core.c:2024
 hci_free_dev+0x19/0x20 net/bluetooth/hci_core.c:3208
ntfs: (device loop1): ntfs_fill_super(): Unable to determine device size.
 vhci_release+0x7e/0xf0 drivers/bluetooth/hci_vhci.c:355
 __fput+0x385/0xa30 fs/file_table.c:278
overlayfs: unrecognized mount option "uperdir=./fil�l�" or missing value
 ____fput+0x15/0x20 fs/file_table.c:309
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x411021
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 34 19 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007fff1507faa0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 0000000000411021
RDX: 0000000000000000 RSI: 0000000000730390 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000730380 R11: 0000000000000293 R12: 0000000000000000
R13: 0000000000000001 R14: 00000000000000a7 R15: 0000000000000003

Allocated by task 11973:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553
 kmem_cache_alloc_trace+0x152/0x750 mm/slab.c:3620
 kmalloc include/linux/slab.h:546 [inline]
 kzalloc include/linux/slab.h:741 [inline]
 hci_alloc_dev+0x228/0x21a0 net/bluetooth/hci_core.c:3116
 __vhci_create_device+0x102/0x580 drivers/bluetooth/hci_vhci.c:114
 vhci_create_device drivers/bluetooth/hci_vhci.c:163 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:219 [inline]
 vhci_write+0x2de/0x470 drivers/bluetooth/hci_vhci.c:299
 call_write_iter include/linux/fs.h:1857 [inline]
 new_sync_write fs/read_write.c:474 [inline]
 __vfs_write+0x6b8/0x9f0 fs/read_write.c:487
 vfs_write+0x1fc/0x560 fs/read_write.c:549
 ksys_write+0x101/0x260 fs/read_write.c:598
 __do_sys_write fs/read_write.c:610 [inline]
 __se_sys_write fs/read_write.c:607 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:607
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 11972:
 save_stack+0x43/0xd0 mm/kasan/kasan.c:448
 set_track mm/kasan/kasan.c:460 [inline]
 __kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
 __cache_free mm/slab.c:3498 [inline]
 kfree+0xcf/0x230 mm/slab.c:3817
 bt_host_release+0x19/0x30 net/bluetooth/hci_sysfs.c:86
 device_release+0x7e/0x210 drivers/base/core.c:891
 kobject_cleanup lib/kobject.c:662 [inline]
 kobject_release lib/kobject.c:691 [inline]
 kref_put include/linux/kref.h:70 [inline]
 kobject_put.cold.9+0x287/0x2e4 lib/kobject.c:708
 put_device+0x20/0x30 drivers/base/core.c:2024
 hci_dev_put include/net/bluetooth/hci_core.h:1014 [inline]
 hci_unregister_dev+0x71d/0x990 net/bluetooth/hci_core.c:3379
 vhci_release+0x76/0xf0 drivers/bluetooth/hci_vhci.c:354
 __fput+0x385/0xa30 fs/file_table.c:278
 ____fput+0x15/0x20 fs/file_table.c:309
 task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff88817f30cc00
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 4300 bytes inside of
 8192-byte region [ffff88817f30cc00, ffff88817f30ec00)
The buggy address belongs to the page:
page:ffffea0005fcc300 count:1 mapcount:0 mapping:ffff8881da802080 index:0x0 compound_mapcount: 0
flags: 0x2fffc0000010200(slab|head)
raw: 02fffc0000010200 ffffea0004e2df08 ffffea00070aa108 ffff8881da802080
raw: 0000000000000000 ffff88817f30cc00 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88817f30db80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88817f30dc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88817f30dc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff88817f30dd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88817f30dd80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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