Bluetooth: hci0: hardware error 0x43
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BUG: KASAN: use-after-free in hci_chan_del+0x14f/0x190 net/bluetooth/hci_conn.c:1728
Read of size 8 at addr ffff8880a5e98818 by task kworker/u5:2/6876

CPU: 0 PID: 6876 Comm: kworker/u5:2 Not tainted 5.8.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: hci0 hci_error_reset
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xae/0x497 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 hci_chan_del+0x14f/0x190 net/bluetooth/hci_conn.c:1728
 l2cap_conn_del+0x61b/0x9e0 net/bluetooth/l2cap_core.c:1900
 l2cap_disconn_cfm net/bluetooth/l2cap_core.c:8160 [inline]
 l2cap_disconn_cfm+0x85/0xa0 net/bluetooth/l2cap_core.c:8153
 hci_disconn_cfm include/net/bluetooth/hci_core.h:1438 [inline]
 hci_conn_hash_flush+0x114/0x220 net/bluetooth/hci_conn.c:1557
 hci_dev_do_close+0x5c6/0x1080 net/bluetooth/hci_core.c:1770
 hci_error_reset+0x90/0xf0 net/bluetooth/hci_core.c:2314
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Allocated by task 6876:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc.constprop.0+0xbf/0xd0 mm/kasan/common.c:461
 kmem_cache_alloc_trace+0x16e/0x2c0 mm/slab.c:3550
 kmalloc include/linux/slab.h:554 [inline]
 kzalloc include/linux/slab.h:666 [inline]
 hci_chan_create+0x9b/0x330 net/bluetooth/hci_conn.c:1713
 l2cap_conn_add.part.0+0x1e/0xe10 net/bluetooth/l2cap_core.c:7698
 l2cap_conn_add net/bluetooth/l2cap_core.c:8140 [inline]
 l2cap_connect_cfm+0x23b/0x1090 net/bluetooth/l2cap_core.c:8098
 hci_connect_cfm include/net/bluetooth/hci_core.h:1423 [inline]
 le_conn_complete_evt+0x1153/0x1740 net/bluetooth/hci_event.c:5190
 hci_le_conn_complete_evt net/bluetooth/hci_event.c:5215 [inline]
 hci_le_meta_evt+0x745/0x3ff0 net/bluetooth/hci_event.c:5915
 hci_event_packet+0x2e25/0x87a8 net/bluetooth/hci_event.c:6192
 hci_rx_work+0x22e/0xb50 net/bluetooth/hci_core.c:4889
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Freed by task 6876:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:56
 kasan_set_free_info+0x1b/0x30 mm/kasan/generic.c:355
 __kasan_slab_free+0xd8/0x120 mm/kasan/common.c:422
 __cache_free mm/slab.c:3418 [inline]
 kfree+0x103/0x2c0 mm/slab.c:3756
 hci_disconn_loglink_complete_evt net/bluetooth/hci_event.c:5018 [inline]
 hci_event_packet+0x3e33/0x87a8 net/bluetooth/hci_event.c:6213
 hci_rx_work+0x22e/0xb50 net/bluetooth/hci_core.c:4889
 process_one_work+0x94c/0x1670 kernel/workqueue.c:2269
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2415
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

The buggy address belongs to the object at ffff8880a5e98800
 which belongs to the cache kmalloc-128 of size 128
The buggy address is located 24 bytes inside of
 128-byte region [ffff8880a5e98800, ffff8880a5e98880)
The buggy address belongs to the page:
page:0000000091b860f4 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880a5e98300 pfn:0xa5e98
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea00029f7208 ffffea00028690c8 ffff8880aa040400
raw: ffff8880a5e98300 ffff8880a5e98000 0000000100000004 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a5e98700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880a5e98780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880a5e98800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff8880a5e98880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a5e98900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
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