------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 14416 at lib/refcount.c:28 refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28
Modules linked in:
CPU: 1 UID: 0 PID: 14416 Comm: syz-executor Not tainted 6.14.0-rc2-syzkaller-00346-gba643b6d8440 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:refcount_warn_saturate+0x14a/0x210 lib/refcount.c:28
Code: ff 89 de e8 68 58 f5 fc 84 db 0f 85 66 ff ff ff e8 bb 5d f5 fc c6 05 d7 5b 86 0b 01 90 48 c7 c7 c0 00 d3 8b e8 f7 96 b5 fc 90 <0f> 0b 90 90 e9 43 ff ff ff e8 98 5d f5 fc 0f b6 1d b2 5b 86 0b 31
RSP: 0018:ffffc900037a78d8 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff817a1229
RDX: ffff888024c70000 RSI: ffffffff817a1236 RDI: 0000000000000001
RBP: ffff88803547a878 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000004 R12: ffff8880352fd000
R13: ffff88803547a878 R14: ffffffff85ebdb20 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff88806a700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c381f07 CR3: 00000000480c0000 CR4: 0000000000352ef0
DR0: 0000000000000008 DR1: 00000000000000ff DR2: fffffffffffffffb
DR3: 3dfffffffffffffd DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __refcount_sub_and_test include/linux/refcount.h:275 [inline]
 __refcount_dec_and_test include/linux/refcount.h:307 [inline]
 refcount_dec_and_test include/linux/refcount.h:325 [inline]
 kref_put include/linux/kref.h:64 [inline]
 klist_dec_and_del lib/klist.c:206 [inline]
 klist_put+0x11b/0x1b0 lib/klist.c:217
 klist_del lib/klist.c:230 [inline]
 klist_remove+0x140/0x2b0 lib/klist.c:249
 device_move+0x12d/0x10b0 drivers/base/core.c:4591
 hci_conn_del_sysfs+0x81/0x180 net/bluetooth/hci_sysfs.c:75
 hci_conn_cleanup net/bluetooth/hci_conn.c:174 [inline]
 hci_conn_del+0x54e/0xdb0 net/bluetooth/hci_conn.c:1164
 hci_conn_hash_flush+0x4bf/0x790 net/bluetooth/hci_conn.c:2699
 hci_dev_close_sync+0x603/0x11a0 net/bluetooth/hci_sync.c:5197
 hci_dev_do_close+0x2e/0x90 net/bluetooth/hci_core.c:482
 hci_unregister_dev+0x213/0x620 net/bluetooth/hci_core.c:2677
 vhci_release+0x79/0xf0 drivers/bluetooth/hci_vhci.c:664
 __fput+0x3ff/0xb70 fs/file_table.c:464
 task_work_run+0x14e/0x250 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0xad8/0x2d70 kernel/exit.c:938
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1087
 __do_sys_exit_group kernel/exit.c:1098 [inline]
 __se_sys_exit_group kernel/exit.c:1096 [inline]
 __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1096
 x64_sys_call+0x151f/0x1720 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f55d6b8cde9
Code: Unable to access opcode bytes at 0x7f55d6b8cdbf.
RSP: 002b:00007ffdabbf20a8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f55d6c0e098 RCX: 00007f55d6b8cde9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000001
RBP: 0000000000000005 R08: 00007ffdabbefe47 R09: 00007ffdabbf3360
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdabbf3360
R13: 00007f55d6c0e08c R14: 0000000000041f96 R15: 00007ffdabbf4430
 </TASK>