netlink: 'syz-executor.3': attribute type 4 has an invalid length.
IPv6: ADDRCONF(NETDEV_CHANGE): lo: link becomes ready
netlink: 'syz-executor.3': attribute type 4 has an invalid length.
syz-executor.3 (8313) used greatest stack depth: 22432 bytes left
==================================================================
BUG: KASAN: use-after-free in hci_chan_del+0x13e/0x180 net/bluetooth/hci_conn.c:1666
Read of size 8 at addr ffff8880969f4558 by task syz-executor.3/8279

CPU: 0 PID: 8279 Comm: syz-executor.3 Not tainted 4.19.146-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x22c/0x33e lib/dump_stack.c:118
 print_address_description.cold+0x56/0x25c mm/kasan/report.c:256
 kasan_report_error.cold+0x66/0xb9 mm/kasan/report.c:354
 kasan_report mm/kasan/report.c:412 [inline]
 __asan_report_load8_noabort+0x88/0x90 mm/kasan/report.c:433
netlink: 12 bytes leftover after parsing attributes in process `syz-executor.5'.
 hci_chan_del+0x13e/0x180 net/bluetooth/hci_conn.c:1666
 l2cap_conn_del+0x44f/0x6b0 net/bluetooth/l2cap_core.c:1736
 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:7435 [inline]
 l2cap_disconn_cfm+0x85/0xa0 net/bluetooth/l2cap_core.c:7428
 hci_disconn_cfm include/net/bluetooth/hci_core.h:1261 [inline]
 hci_conn_hash_flush+0x114/0x220 net/bluetooth/hci_conn.c:1495
 hci_dev_do_close+0x623/0xe70 net/bluetooth/hci_core.c:1666
 hci_unregister_dev+0x17c/0x7f0 net/bluetooth/hci_core.c:3271
 vhci_release+0x70/0xe0 drivers/bluetooth/hci_vhci.c:354
 __fput+0x2ce/0x8a0 fs/file_table.c:278
 task_work_run+0x141/0x1c0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xc09/0x2d80 kernel/exit.c:887
 do_group_exit+0x125/0x320 kernel/exit.c:990
 get_signal+0x3f3/0x2270 kernel/signal.c:2588
 do_signal+0x8f/0x1690 arch/x86/kernel/signal.c:821
 exit_to_usermode_loop+0x204/0x2c0 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:198 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:271 [inline]
 do_syscall_64+0x57c/0x670 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45d5f9
Code: Bad RIP value.
RSP: 002b:00007f58d3b41cf8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 000000000118cf48 RCX: 000000000045d5f9
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 000000000118cf48
RBP: 000000000118cf40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000118cf4c
R13: 00007fff071bd0ff R14: 00007f58d3b429c0 R15: 000000000118cf4c

Allocated by task 1230:
 kmem_cache_alloc_trace+0x12f/0x4b0 mm/slab.c:3625
 kmalloc include/linux/slab.h:515 [inline]
 kzalloc include/linux/slab.h:709 [inline]
 hci_chan_create+0x8e/0x310 net/bluetooth/hci_conn.c:1651
 l2cap_conn_add+0x5c/0xc60 net/bluetooth/l2cap_core.c:7056
 l2cap_connect_cfm+0x15b/0xe10 net/bluetooth/l2cap_core.c:7373
 hci_connect_cfm include/net/bluetooth/hci_core.h:1246 [inline]
 le_conn_complete_evt+0x11ed/0x1830 net/bluetooth/hci_event.c:4938
 hci_le_enh_conn_complete_evt net/bluetooth/hci_event.c:4980 [inline]
 hci_le_meta_evt net/bluetooth/hci_event.c:5668 [inline]
 hci_event_packet+0x447c/0x81a2 net/bluetooth/hci_event.c:5904
 hci_rx_work+0x4c5/0xb50 net/bluetooth/hci_core.c:4359
 process_one_work+0x796/0x14e0 kernel/workqueue.c:2155
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2298
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Freed by task 1230:
 __cache_free mm/slab.c:3503 [inline]
 kfree+0xcc/0x250 mm/slab.c:3822
 hci_disconn_loglink_complete_evt net/bluetooth/hci_event.c:4765 [inline]
 hci_event_packet+0xec3/0x81a2 net/bluetooth/hci_event.c:5925
 hci_rx_work+0x4c5/0xb50 net/bluetooth/hci_core.c:4359
 process_one_work+0x796/0x14e0 kernel/workqueue.c:2155
 worker_thread+0x64c/0x1130 kernel/workqueue.c:2298
 kthread+0x33f/0x460 kernel/kthread.c:259
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

The buggy address belongs to the object at ffff8880969f4540
 which belongs to the cache kmalloc-128 of size 128
The buggy address is located 24 bytes inside of
 128-byte region [ffff8880969f4540, ffff8880969f45c0)
The buggy address belongs to the page:
page:ffffea00025a7d00 count:1 mapcount:0 mapping:ffff88812c3f6640 index:0x0
flags: 0xfffe0000000100(slab)
raw: 00fffe0000000100 ffffea00027a2cc8 ffffea00025d1888 ffff88812c3f6640
raw: 0000000000000000 ffff8880969f4000 0000000100000015 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880969f4400: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8880969f4480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880969f4500: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                                    ^
 ffff8880969f4580: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff8880969f4600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================