------------[ cut here ]------------
kobject: '(efault)' (00000000f91674ed): is not initialized, yet kobject_put() is being called.
WARNING: CPU: 0 PID: 7004 at lib/kobject.c:752 kobject_put+0x8c/0xc0 lib/kobject.c:750
Modules linked in:
CPU: 0 PID: 7004 Comm: syz-executor.1 Not tainted 5.10.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:kobject_put+0x8c/0xc0 lib/kobject.c:750
Code: 74 08 4c 89 ef e8 44 b5 56 ff 4d 85 f6 4c 89 f3 74 bf f6 43 3c 01 75 a5 48 8b 33 48 89 da 48 c7 c7 60 99 19 84 e8 aa fd 36 01 <0f> 0b eb 8f c3 5b be 03 00 00 00 5d 41 5c 41 5d 41 5e e9 ed e9 f7
RSP: 0018:ffffc90000e6fca8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff88811d682c18 RCX: 0000000000000001
RDX: 0000000080000001 RSI: ffffffff842a1aa6 RDI: 00000000ffffffff
RBP: 00000000ffffffff R08: 0000000000000001 R09: 0000000000000001
R10: ffffc90000e6fad8 R11: ffffc90000e6fad0 R12: ffff88810c091660
R13: ffff88810c091708 R14: ffff88810c0911d8 R15: ffff88810c0911d8
FS:  0000000000000000(0000) GS:ffff88813bc00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f486da49038 CR3: 000000010d3cd000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 hci_conn_put include/net/bluetooth/hci_core.h:1104 [inline]
 hci_chan_del+0x47/0x60 net/bluetooth/hci_conn.c:1740
 l2cap_conn_del.isra.53+0x1c6/0x2a0 net/bluetooth/l2cap_core.c:1900
 hci_disconn_cfm include/net/bluetooth/hci_core.h:1441 [inline]
 hci_conn_hash_flush+0x64/0xc0 net/bluetooth/hci_conn.c:1557
 hci_dev_do_close+0x1ed/0x500 net/bluetooth/hci_core.c:1770
 hci_unregister_dev+0xc0/0x2c0 net/bluetooth/hci_core.c:3827
 vhci_release+0x2a/0x60 drivers/bluetooth/hci_vhci.c:340
 __fput+0xaa/0x250 fs/file_table.c:281
 task_work_run+0x68/0xb0 kernel/task_work.c:151
 exit_task_work include/linux/task_work.h:30 [inline]
 do_exit+0x3b0/0xc90 kernel/exit.c:809
 do_group_exit+0x42/0xb0 kernel/exit.c:906
 __do_sys_exit_group kernel/exit.c:917 [inline]
 __se_sys_exit_group kernel/exit.c:915 [inline]
 __x64_sys_exit_group+0xf/0x10 kernel/exit.c:915
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45de59
Code: Unable to access opcode bytes at RIP 0x45de2f.
RSP: 002b:00007fff74643778 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000016 RCX: 000000000045de59
RDX: 00000000004176f1 RSI: 00000000016a9df0 RDI: 0000000000000000
RBP: 00000000004c292f R08: 000000000000000c R09: 0000000000000000
R10: 0000000002317940 R11: 0000000000000246 R12: 00007fff74644a20
R13: 0000000002320aa0 R14: 0000000000000000 R15: 00007fff74645ab0