==================================================================
BUG: KASAN: slab-use-after-free in hci_conn_hash_flush+0x201/0x240
Read of size 8 at addr ffff88803ebb6000 by task syz-executor.4/13127

CPU: 1 PID: 13127 Comm: syz-executor.4 Not tainted 6.3.0-rc7-next-20230419 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x91/0xf0
 print_report+0xcc/0x620
 kasan_report+0xc0/0xf0
 hci_conn_hash_flush+0x201/0x240
 hci_dev_close_sync+0x57f/0xff0
 hci_rfkill_set_block+0x17b/0x1c0
 rfkill_set_block+0x1fd/0x540
 rfkill_fop_write+0x2b7/0x540
 vfs_write+0x2d8/0xdd0
 ksys_write+0x1f4/0x260
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7f31d6810b19
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f31d3d86188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f31d6923f60 RCX: 00007f31d6810b19
RDX: 0000000000000008 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 00007f31d686af6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffecb7a72bf R14: 00007f31d3d86300 R15: 0000000000022000
 </TASK>

Allocated by task 8289:
 kasan_save_stack+0x22/0x50
 kasan_set_track+0x25/0x30
 __kasan_kmalloc+0x7f/0x90
 hci_conn_add+0xa3/0x14d0
 hci_connect_sco+0x3e7/0x1120
 sco_sock_connect+0x2c0/0x9c0
 __sys_connect_file+0x159/0x1a0
 __sys_connect+0x169/0x1a0
 __x64_sys_connect+0x73/0xb0
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

Freed by task 13127:
 kasan_save_stack+0x22/0x50
 kasan_set_track+0x25/0x30
 kasan_save_free_info+0x2e/0x50
 __kasan_slab_free+0x10a/0x190
 __kmem_cache_free+0xd1/0x2f0
 device_release+0xa6/0x240
 kobject_put+0x177/0x270
 put_device+0x1f/0x30
 hci_conn_del+0x29f/0x810
 hci_conn_unlink+0x211/0x390
 hci_conn_unlink+0x2a3/0x390
 hci_conn_hash_flush+0x195/0x240
 hci_dev_close_sync+0x57f/0xff0
 hci_rfkill_set_block+0x17b/0x1c0
 rfkill_set_block+0x1fd/0x540
 rfkill_fop_write+0x2b7/0x540
 vfs_write+0x2d8/0xdd0
 ksys_write+0x1f4/0x260
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

Last potentially related work creation:
 kasan_save_stack+0x22/0x50
 __kasan_record_aux_stack+0x95/0xb0
 __queue_work+0x622/0x12f0
 __queue_delayed_work+0x1c8/0x270
 queue_delayed_work_on+0xcd/0xd0
 sco_chan_del+0x1db/0x440
 __sco_sock_close+0x21e/0x770
 sco_sock_release+0xa1/0x400
 __sock_release+0xd2/0x2a0
 sock_close+0x1c/0x30
 __fput+0x263/0xa40
 task_work_run+0x174/0x280
 get_signal+0x1d3/0x26c0
 arch_do_signal_or_restart+0x79/0x590
 exit_to_user_mode_prepare+0xeb/0x180
 syscall_exit_to_user_mode+0x1d/0x50
 do_syscall_64+0x4c/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

The buggy address belongs to the object at ffff88803ebb6000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 0 bytes inside of
 freed 4096-byte region [ffff88803ebb6000, ffff88803ebb7000)

The buggy address belongs to the physical page:
page:0000000054a68740 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3ebb0
head:0000000054a68740 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0x100000000010200(slab|head|node=0|zone=1)
page_type: 0xffffffff()
raw: 0100000000010200 ffff888008442140 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000040004 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88803ebb5f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88803ebb5f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88803ebb6000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88803ebb6080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88803ebb6100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
general protection fault, probably for non-canonical address 0xe08adc4fa0000668: 0000 [#1] PREEMPT SMP KASAN NOPTI
KASAN: maybe wild-memory-access in range [0x0457027d00003340-0x0457027d00003347]
CPU: 1 PID: 13127 Comm: syz-executor.4 Tainted: G    B              6.3.0-rc7-next-20230419 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:hci_conn_cleanup+0x1c5/0x780
Code: fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 ef 04 00 00 48 89 da 49 89 5c 24 08 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 ab 04 00 00 48 b8 22 01 00 00 00 00 ad de 4c 89
RSP: 0018:ffff88803ff1fab0 EFLAGS: 00010213
RAX: dffffc0000000000 RBX: 0457027d00003347 RCX: ffffffff83da1c83
RDX: 008ae04fa0000668 RSI: 0000000000000008 RDI: ffff88800dc0d008
RBP: ffff88803ebb6000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88800dc0d000
R13: ffff88803ebb6260 R14: dffffc0000000000 R15: ffff88803e168000
FS:  00007f31d3d86700(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efc51741330 CR3: 00000000410e6000 CR4: 0000000000350ee0
Call Trace:
 <TASK>
 hci_conn_del+0x29f/0x810
 hci_conn_hash_flush+0x19d/0x240
 hci_dev_close_sync+0x57f/0xff0
 hci_rfkill_set_block+0x17b/0x1c0
 rfkill_set_block+0x1fd/0x540
 rfkill_fop_write+0x2b7/0x540
 vfs_write+0x2d8/0xdd0
 ksys_write+0x1f4/0x260
 do_syscall_64+0x3f/0x90
 entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7f31d6810b19
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f31d3d86188 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f31d6923f60 RCX: 00007f31d6810b19
RDX: 0000000000000008 RSI: 0000000020000080 RDI: 0000000000000003
RBP: 00007f31d686af6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffecb7a72bf R14: 00007f31d3d86300 R15: 0000000000022000
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:hci_conn_cleanup+0x1c5/0x780
Code: fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 ef 04 00 00 48 89 da 49 89 5c 24 08 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <80> 3c 02 00 0f 85 ab 04 00 00 48 b8 22 01 00 00 00 00 ad de 4c 89
RSP: 0018:ffff88803ff1fab0 EFLAGS: 00010213
RAX: dffffc0000000000 RBX: 0457027d00003347 RCX: ffffffff83da1c83
RDX: 008ae04fa0000668 RSI: 0000000000000008 RDI: ffff88800dc0d008
RBP: ffff88803ebb6000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88800dc0d000
R13: ffff88803ebb6260 R14: dffffc0000000000 R15: ffff88803e168000
FS:  00007f31d3d86700(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007efc51741330 CR3: 00000000410e6000 CR4: 0000000000350ee0
----------------
Code disassembly (best guess), 2 bytes skipped:
   0:	df 48 89             	fisttps -0x77(%rax)
   3:	fa                   	cli
   4:	48 c1 ea 03          	shr    $0x3,%rdx
   8:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1)
   c:	0f 85 ef 04 00 00    	jne    0x501
  12:	48 89 da             	mov    %rbx,%rdx
  15:	49 89 5c 24 08       	mov    %rbx,0x8(%r12)
  1a:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  21:	fc ff df
  24:	48 c1 ea 03          	shr    $0x3,%rdx
* 28:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2c:	0f 85 ab 04 00 00    	jne    0x4dd
  32:	48 b8 22 01 00 00 00 	movabs $0xdead000000000122,%rax
  39:	00 ad de
  3c:	4c                   	rex.WR
  3d:	89                   	.byte 0x89