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BUG: KCSAN: data-race in __hci_cmd_sync_sk / hci_cmd_sync_cancel_sync

write to 0xffff88810b33c8f8 of 4 bytes by task 44 on cpu 1:
 hci_cmd_sync_cancel_sync+0x67/0xa0 net/bluetooth/hci_sync.c:691
 hci_send_cmd_sync net/bluetooth/hci_core.c:4119 [inline]
 hci_cmd_work+0x27a/0x320 net/bluetooth/hci_core.c:4152
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3340
 worker_thread+0x582/0x770 kernel/workqueue.c:3421
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x149/0x290 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

read to 0xffff88810b33c8f8 of 4 bytes by task 5534 on cpu 0:
 __hci_cmd_sync_sk+0x34f/0x640 net/bluetooth/hci_sync.c:176
 __hci_cmd_sync_status_sk net/bluetooth/hci_sync.c:263 [inline]
 __hci_cmd_sync_status net/bluetooth/hci_sync.c:287 [inline]
 hci_cmd_sync_status+0x4b/0x100 net/bluetooth/hci_sync.c:298
 hci_dev_cmd+0x4e4/0x500 net/bluetooth/hci_core.c:-1
 hci_sock_ioctl+0x578/0x7f0 net/bluetooth/hci_sock.c:1157
 sock_do_ioctl+0x73/0x220 net/socket.c:1254
 sock_ioctl+0x41b/0x610 net/socket.c:1375
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583
 x64_sys_call+0x14b0/0x3000 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd8/0x2a0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000001 -> 0x00000002

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 5534 Comm: syz.2.673 Not tainted syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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Bluetooth: hci0: Opcode 0x0c20 failed: -22