------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 5833 at lib/refcount.c:28 refcount_warn_saturate+0x15a/0x1d0 lib/refcount.c:28
Modules linked in:
CPU: 1 UID: 0 PID: 5833 Comm: kworker/u9:2 Not tainted 6.14.0-rc5-syzkaller-01188-g0ea09cbf8350 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: hci4 hci_cmd_sync_work
RIP: 0010:refcount_warn_saturate+0x15a/0x1d0 lib/refcount.c:28
Code: c0 b2 80 8c e8 27 21 8c fc 90 0f 0b 90 90 eb 99 e8 9b 64 cc fc c6 05 e9 ac 31 0b 01 90 48 c7 c7 20 b3 80 8c e8 07 21 8c fc 90 <0f> 0b 90 90 e9 76 ff ff ff e8 78 64 cc fc c6 05 c3 ac 31 0b 01 90
RSP: 0018:ffffc9000421f618 EFLAGS: 00010246
RAX: 323419de489aaa00 RBX: ffff88803567e478 RCX: ffff888035080000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 0000000000000003 R08: ffffffff81819e32 R09: 1ffff110170e519a
R10: dffffc0000000000 R11: ffffed10170e519b R12: ffff88803567e460
R13: ffffffff8638bc20 R14: 1ffff11006acfc8c R15: ffff88803567e460
FS:  0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c2597bd CR3: 00000000606b4000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 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+0x3ec/0x3f0 lib/klist.c:206
 klist_put lib/klist.c:217 [inline]
 klist_del lib/klist.c:230 [inline]
 klist_remove+0x25e/0x480 lib/klist.c:249
 device_move+0x1b4/0x710 drivers/base/core.c:4591
 hci_conn_del_sysfs+0xb5/0x170 net/bluetooth/hci_sysfs.c:75
 hci_conn_cleanup net/bluetooth/hci_conn.c:174 [inline]
 hci_conn_del+0x8c4/0xc40 net/bluetooth/hci_conn.c:1164
 hci_conn_failed+0x319/0x400 net/bluetooth/hci_conn.c:1267
 hci_abort_conn_sync+0xd27/0x1340 net/bluetooth/hci_sync.c:5588
 hci_cmd_sync_work+0x22b/0x400 net/bluetooth/hci_sync.c:332
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319
 worker_thread+0x870/0xd30 kernel/workqueue.c:3400
 kthread+0x7a9/0x920 kernel/kthread.c:464
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>