==================================================================
BUG: KASAN: slab-use-after-free in hci_conn_drop+0x34/0x2a0
Write of size 4 at addr ffff888175790010 by task kworker/u11:4/5599

CPU: 1 UID: 0 PID: 5599 Comm: kworker/u11:4 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: hci1 hci_cmd_sync_work
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 print_report+0xba/0x230
 kasan_report+0x117/0x150
 kasan_check_range+0x264/0x2c0
 hci_conn_drop+0x34/0x2a0
 hci_cmd_sync_work+0x25a/0x3f0
 process_scheduled_works+0xa2f/0x1470
 worker_thread+0xa44/0xfb0
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Allocated by task 5599:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x318/0x660
 __hci_conn_add+0x3c4/0x1dd0
 le_conn_complete_evt+0x6bc/0x1360
 hci_le_enh_conn_complete_evt+0x189/0x490
 hci_event_packet+0x7af/0x12a0
 hci_rx_work+0x3ee/0x1010
 process_scheduled_works+0xa2f/0x1470
 worker_thread+0xa44/0xfb0
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30

Freed by task 56:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x40/0x50
 __kasan_slab_free+0x5c/0x80
 kfree+0x1c1/0x630
 device_release+0x9e/0x1d0
 kobject_put+0x222/0x550
 hci_conn_del+0xc3d/0x1200
 hci_disconn_complete_evt+0x64f/0x940
 hci_event_packet+0x803/0x12a0
 hci_rx_work+0x3ee/0x1010
 process_scheduled_works+0xa2f/0x1470
 worker_thread+0xa44/0xfb0
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 ret_from_fork_asm+0x1a/0x30

The buggy address belongs to the object at ffff888175790000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 16 bytes inside of
 freed 8192-byte region [ffff888175790000, ffff888175792000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x175790
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x57ff00000000040(head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000040 ffff888100042280 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800020002 00000000f5000000 0000000000000000
head: 057ff00000000040 ffff888100042280 dead000000000100 dead000000000122
head: 0000000000000000 0000000800020002 00000000f5000000 0000000000000000
head: 057ff00000000003 ffffea0005d5e401 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5059, tgid 5059 (udevd), ts 25960725896, free_ts 24693325972
 post_alloc_hook+0x231/0x280
 get_page_from_freelist+0x2503/0x25a0
 __alloc_frozen_pages_noprof+0x18d/0x380
 allocate_slab+0x77/0x660
 refill_objects+0x32e/0x3c0
 __pcs_replace_empty_main+0x2f9/0x5e0
 __kmalloc_cache_noprof+0x388/0x660
 tomoyo_init_log+0x112e/0x1fa0
 tomoyo_supervisor+0x35f/0x1560
 tomoyo_env_perm+0x151/0x1f0
 tomoyo_find_next_domain+0x1332/0x1a90
 tomoyo_bprm_check_security+0x11b/0x180
 security_bprm_check+0x85/0x240
 bprm_execve+0x916/0x1580
 do_execveat_common+0x4f1/0x670
 __x64_sys_execve+0x97/0xc0
page last free pid 5042 tgid 5042 stack trace:
 __free_frozen_pages+0xc14/0xda0
 __slab_free+0x263/0x2b0
 qlist_free_all+0x98/0x100
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 __kmalloc_noprof+0x312/0x750
 tomoyo_realpath_from_path+0xef/0x640
 tomoyo_check_open_permission+0x229/0x470
 security_file_open+0xa9/0x240
 do_dentry_open+0x4a0/0x1380
 vfs_open+0x3b/0x340
 path_openat+0x2e3b/0x3890
 do_file_open+0x23e/0x4a0
 do_sys_openat2+0x113/0x200
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0x170/0xf80

Memory state around the buggy address:
 ffff88817578ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88817578ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888175790000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff888175790080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888175790100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
