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BUG: KASAN: wild-memory-access in instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
BUG: KASAN: wild-memory-access in atomic_fetch_sub_release include/asm-generic/atomic-instrumented.h:220 [inline]
BUG: KASAN: wild-memory-access in __refcount_sub_and_test include/linux/refcount.h:272 [inline]
BUG: KASAN: wild-memory-access in __refcount_dec_and_test include/linux/refcount.h:315 [inline]
BUG: KASAN: wild-memory-access in refcount_dec_and_test include/linux/refcount.h:333 [inline]
BUG: KASAN: wild-memory-access in kref_put include/linux/kref.h:64 [inline]
BUG: KASAN: wild-memory-access in l2cap_chan_put+0x35/0x2e0 net/bluetooth/l2cap_core.c:502
Write of size 4 at addr 0880000100080028 by task syz-executor.5/8444

CPU: 1 PID: 8444 Comm: syz-executor.5 Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0xfa/0x151 lib/dump_stack.c:120
 __kasan_report mm/kasan/report.c:400 [inline]
 kasan_report.cold+0x5f/0xd5 mm/kasan/report.c:413
 check_memory_region_inline mm/kasan/generic.c:179 [inline]
 check_memory_region+0x13d/0x180 mm/kasan/generic.c:185
 instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
 atomic_fetch_sub_release include/asm-generic/atomic-instrumented.h:220 [inline]
 __refcount_sub_and_test include/linux/refcount.h:272 [inline]
 __refcount_dec_and_test include/linux/refcount.h:315 [inline]
 refcount_dec_and_test include/linux/refcount.h:333 [inline]
 kref_put include/linux/kref.h:64 [inline]
 l2cap_chan_put+0x35/0x2e0 net/bluetooth/l2cap_core.c:502
 l2cap_sock_kill+0xd0/0x240 net/bluetooth/l2cap_sock.c:1217
 l2cap_conn_del+0x3fc/0x7b0 net/bluetooth/l2cap_core.c:1898
 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:8168 [inline]
 l2cap_disconn_cfm+0x98/0xd0 net/bluetooth/l2cap_core.c:8161
 hci_disconn_cfm include/net/bluetooth/hci_core.h:1486 [inline]
 hci_conn_hash_flush+0x127/0x260 net/bluetooth/hci_conn.c:1598
 hci_dev_do_close+0x569/0x1110 net/bluetooth/hci_core.c:1778
 hci_unregister_dev+0x263/0x1130 net/bluetooth/hci_core.c:3989
 vhci_release+0x70/0xe0 drivers/bluetooth/hci_vhci.c:340
 __fput+0x288/0x920 fs/file_table.c:280
 task_work_run+0xdd/0x1a0 kernel/task_work.c:140
 exit_task_work include/linux/task_work.h:30 [inline]
 do_exit+0xc61/0x2ae0 kernel/exit.c:825
 do_group_exit+0x125/0x310 kernel/exit.c:922
 __do_sys_exit_group kernel/exit.c:933 [inline]
 __se_sys_exit_group kernel/exit.c:931 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:931
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x465ef9
Code: Unable to access opcode bytes at RIP 0x465ecf.
RSP: 002b:00007ffdc12d75e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000002120 RCX: 0000000000465ef9
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000043
RBP: 0000000000000000 R08: 0000000000000014 R09: 0000000000002120
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000004bce67
R13: 0000000000000000 R14: 0000000000000005 R15: 00007ffdc12d77e0
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