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BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:112 [inline]
BUG: KASAN: slab-use-after-free in atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1383 [inline]
BUG: KASAN: slab-use-after-free in hci_conn_drop+0x34/0x2a0 include/net/bluetooth/hci_core.h:1690
Write of size 4 at addr ffff888012534010 by task kworker/u5:1/4669

CPU: 0 UID: 0 PID: 4669 Comm: kworker/u5:1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: hci0 hci_cmd_sync_work
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xba/0x230 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x264/0x2c0 mm/kasan/generic.c:200
 instrument_atomic_read_write include/linux/instrumented.h:112 [inline]
 atomic_dec_and_test include/linux/atomic/atomic-instrumented.h:1383 [inline]
 hci_conn_drop+0x34/0x2a0 include/net/bluetooth/hci_core.h:1690
 hci_cmd_sync_work+0x262/0x400 net/bluetooth/hci_sync.c:334
 process_one_work kernel/workqueue.c:3275 [inline]
 process_scheduled_works+0xb02/0x1830 kernel/workqueue.c:3358
 worker_thread+0xa50/0xfc0 kernel/workqueue.c:3439
 kt[   84.943298][ T4669] Bluetooth: hci0: command tx timeout
Bluetooth: hci0: command tx timeout