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BUG: KASAN: use-after-free in __lock_acquire+0x3e90/0x5500 kernel/locking/lockdep.c:4772
Read of size 8 at addr ffff888010cae0a0 by task kworker/1:4/8636

CPU: 1 PID: 8636 Comm: kworker/1:4 Not tainted 5.13.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events l2cap_chan_timeout
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x93/0xc2 lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5b/0x2c6 mm/kasan/report.c:233
 __kasan_report mm/kasan/report.c:419 [inline]
 kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:436
 __lock_acquire+0x3e90/0x5500 kernel/locking/lockdep.c:4772
 lock_acquire kernel/locking/lockdep.c:5512 [inline]
 lock_acquire+0x1ab/0x730 kernel/locking/lockdep.c:5477
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
 _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:175
 spin_lock_bh include/linux/spinlock.h:359 [inline]
 lock_sock_nested+0x39/0xf0 net/core/sock.c:3065
 l2cap_sock_teardown_cb+0x90/0x590 net/bluetooth/l2cap_sock.c:1528
 l2cap_chan_del+0x9b/0x8f0 net/bluetooth/l2cap_core.c:622
 l2cap_chan_close+0x183/0x990 net/bluetooth/l2cap_core.c:825
 l2cap_chan_timeout+0x125/0x280 net/bluetooth/l2cap_core.c:436
 process_one_work+0x84c/0x13d0 kernel/workqueue.c:2276
 worker_thread+0x598/0xf80 kernel/workqueue.c:2422
 kthread+0x36f/0x450 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294

Allocated by task 4869:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:428 [inline]
 ____kasan_kmalloc mm/kasan/common.c:507 [inline]
 __kasan_kmalloc+0x7a/0x90 mm/kasan/common.c:516
 kasan_kmalloc include/linux/kasan.h:246 [inline]
 __do_kmalloc mm/slab.c:3702 [inline]
 __kmalloc+0x196/0x380 mm/slab.c:3711
 kmalloc include/linux/slab.h:561 [inline]
 sk_prot_alloc+0xee/0x200 net/core/sock.c:1711
 sk_alloc+0x27/0x910 net/core/sock.c:1764
 __netlink_create+0x58/0x2d0 net/netlink/af_netlink.c:640
 netlink_create+0x305/0x540 net/netlink/af_netlink.c:703
 __sock_create+0x2a2/0x5b0 net/socket.c:1395
 sock_create net/socket.c:1446 [inline]
 __sys_socket+0xd6/0x1a0 net/socket.c:1488
 __do_sys_socket net/socket.c:1497 [inline]
 __se_sys_socket net/socket.c:1495 [inline]
 __x64_sys_socket+0x6a/0xb0 net/socket.c:1495
 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 0:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_set_track+0x1c/0x30 mm/kasan/common.c:46
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:357
 ____kasan_slab_free mm/kasan/common.c:360 [inline]
 ____kasan_slab_free mm/kasan/common.c:325 [inline]
 __kasan_slab_free+0xb2/0xe0 mm/kasan/common.c:368
 kasan_slab_free include/linux/kasan.h:212 [inline]
 __cache_free mm/slab.c:3445 [inline]
 kfree+0xeb/0x280 mm/slab.c:3803
 sk_prot_free net/core/sock.c:1747 [inline]
 __sk_destruct+0x54e/0x740 net/core/sock.c:1832
 rcu_do_batch kernel/rcu/tree.c:2558 [inline]
 rcu_core+0x7ab/0x13b0 kernel/rcu/tree.c:2793
 __do_softirq+0x29b/0xa40 kernel/softirq.c:559

Last potentially related work creation:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:38
 kasan_record_aux_stack+0x87/0xb0 mm/kasan/generic.c:345
 __call_rcu kernel/rcu/tree.c:3038 [inline]
 call_rcu+0xb1/0x720 kernel/rcu/tree.c:3113
 netlink_release+0xba2/0x1850 net/netlink/af_netlink.c:812
 __sock_release+0xbb/0x270 net/socket.c:599
 sock_close+0xf/0x20 net/socket.c:1245
 __fput+0x209/0x870 fs/file_table.c:280
 task_work_run+0xc0/0x160 kernel/task_work.c:164
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0xa26/0x2510 kernel/exit.c:826
 do_group_exit+0xe7/0x290 kernel/exit.c:923
 __do_sys_exit_group kernel/exit.c:934 [inline]
 __se_sys_exit_group kernel/exit.c:932 [inline]
 __x64_sys_exit_group+0x35/0x40 kernel/exit.c:932
 do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff888010cae000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 160 bytes inside of
 2048-byte region [ffff888010cae000, ffff888010cae800)
The buggy address belongs to the page:
page:000000003fea4bb1 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10cae
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 ffffea000044c288 ffffea00004bd088 ffff88800f440800
raw: 0000000000000000 ffff888010cae000 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff888010cadf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888010cae000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888010cae080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff888010cae100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888010cae180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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