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BUG: KASAN: slab-out-of-bounds in hci_le_direct_adv_report_evt net/bluetooth/hci_event.c:5875 [inline]
BUG: KASAN: slab-out-of-bounds in hci_le_meta_evt+0x3937/0x3ff0 net/bluetooth/hci_event.c:5939
Read of size 1 at addr ffff8880a85c8a0c by task kworker/u5:0/1537

CPU: 1 PID: 1537 Comm: kworker/u5:0 Not tainted 5.8.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: hci2 hci_rx_work
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/0x436 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 hci_le_direct_adv_report_evt net/bluetooth/hci_event.c:5875 [inline]
 hci_le_meta_evt+0x3937/0x3ff0 net/bluetooth/hci_event.c:5939
 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

Allocated by task 20809:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:494
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0xae/0x550 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1084 [inline]
 bt_skb_alloc include/net/bluetooth/bluetooth.h:389 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:165 [inline]
 vhci_write+0xbd/0x450 drivers/bluetooth/hci_vhci.c:285
 call_write_iter include/linux/fs.h:1872 [inline]
 new_sync_write+0x422/0x650 fs/read_write.c:503
 vfs_write+0x5ad/0x730 fs/read_write.c:578
 ksys_write+0x12d/0x250 fs/read_write.c:631
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 28830:
 save_stack+0x1b/0x40 mm/kasan/common.c:48
 set_track mm/kasan/common.c:56 [inline]
 kasan_set_free_info mm/kasan/common.c:316 [inline]
 __kasan_slab_free+0xf5/0x140 mm/kasan/common.c:455
 __cache_free mm/slab.c:3426 [inline]
 kfree+0x103/0x2c0 mm/slab.c:3757
 batadv_iv_send_outstanding_bat_ogm_packet+0x2b5/0x800 net/batman-adv/bat_iv_ogm.c:1729
 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 ffff8880a85c8800
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 12 bytes to the right of
 512-byte region [ffff8880a85c8800, ffff8880a85c8a00)
The buggy address belongs to the page:
page:ffffea0002a17200 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880a85c8c00
flags: 0xfffe0000000200(slab)
raw: 00fffe0000000200 ffffea0002671ac8 ffffea0002449388 ffff8880aa040a80
raw: ffff8880a85c8c00 ffff8880a85c8000 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff8880a85c8900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8880a85c8980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880a85c8a00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                      ^
 ffff8880a85c8a80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880a85c8b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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