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BUG: KASAN: use-after-free in __lock_acquire+0x3f13/0x57d0 kernel/locking/lockdep.c:4702
Read of size 8 at addr ffff88802f43c0a0 by task kworker/1:2/3532

CPU: 1 PID: 3532 Comm: kworker/1:2 Not tainted 5.11.0-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+0x9a/0xcc lib/dump_stack.c:120
 print_address_description.constprop.0.cold+0x5b/0x2f8 mm/kasan/report.c:230
 __kasan_report mm/kasan/report.c:396 [inline]
 kasan_report.cold+0x79/0xd5 mm/kasan/report.c:413
 __lock_acquire+0x3f13/0x57d0 kernel/locking/lockdep.c:4702
 lock_acquire kernel/locking/lockdep.c:5442 [inline]
 lock_acquire+0x1a8/0x720 kernel/locking/lockdep.c:5407
 __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+0x34/0xf0 net/core/sock.c:3049
 l2cap_sock_teardown_cb+0x90/0x590 net/bluetooth/l2cap_sock.c:1520
 l2cap_chan_close+0x304/0x990 net/bluetooth/l2cap_core.c:832
 l2cap_chan_timeout+0x125/0x280 net/bluetooth/l2cap_core.c:436
 process_one_work+0x828/0x1390 kernel/workqueue.c:2275
 worker_thread+0x598/0xf80 kernel/workqueue.c:2421
 kthread+0x36f/0x450 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Allocated by task 7671:
 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:401 [inline]
 ____kasan_kmalloc.constprop.0+0x82/0xa0 mm/kasan/common.c:429
 kmalloc include/linux/slab.h:557 [inline]
 sk_prot_alloc+0x133/0x260 net/core/sock.c:1685
 sk_alloc+0x27/0x8d0 net/core/sock.c:1739
 l2cap_sock_alloc.constprop.0+0x22/0x200 net/bluetooth/l2cap_sock.c:1805
 l2cap_sock_create+0xc8/0x160 net/bluetooth/l2cap_sock.c:1851
 bt_sock_create+0x142/0x2e0 net/bluetooth/af_bluetooth.c:130
 __sock_create+0x26b/0x580 net/socket.c:1406
 sock_create net/socket.c:1457 [inline]
 __sys_socket+0xd6/0x1a0 net/socket.c:1499
 __do_sys_socket net/socket.c:1508 [inline]
 __se_sys_socket net/socket.c:1506 [inline]
 __x64_sys_socket+0x6a/0xb0 net/socket.c:1506
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Freed by task 7671:
 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:356
 ____kasan_slab_free+0xe1/0x110 mm/kasan/common.c:362
 kasan_slab_free include/linux/kasan.h:192 [inline]
 slab_free_hook mm/slub.c:1547 [inline]
 slab_free_freelist_hook+0x5d/0x150 mm/slub.c:1580
 slab_free mm/slub.c:3143 [inline]
 kfree+0xdb/0x3b0 mm/slub.c:4139
 sk_prot_free net/core/sock.c:1722 [inline]
 __sk_destruct+0x53f/0x730 net/core/sock.c:1807
 l2cap_sock_release+0x16b/0x1e0 net/bluetooth/l2cap_sock.c:1389
 __sock_release+0xbb/0x270 net/socket.c:597
 sock_close+0xf/0x20 net/socket.c:1256
 __fput+0x204/0x870 fs/file_table.c:280
 task_work_run+0xc0/0x160 kernel/task_work.c:140
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x249/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
 syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff88802f43c000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 160 bytes inside of
 2048-byte region [ffff88802f43c000, ffff88802f43c800)
The buggy address belongs to the page:
page:0000000053367472 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2f438
head:0000000053367472 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff88800f442000
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x152a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 7669, ts 79692578921
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x144/0x1c0 mm/page_alloc.c:2297
 prep_new_page mm/page_alloc.c:2306 [inline]
 get_page_from_freelist+0x1c6e/0x3f80 mm/page_alloc.c:3945
 __alloc_pages_nodemask+0x2d6/0x730 mm/page_alloc.c:4995
 alloc_pages include/linux/gfp.h:547 [inline]
 alloc_slab_page mm/slub.c:1618 [inline]
 allocate_slab+0x2b6/0x4a0 mm/slub.c:1758
 new_slab mm/slub.c:1821 [inline]
 new_slab_objects mm/slub.c:2578 [inline]
 ___slab_alloc+0x476/0x790 mm/slub.c:2741
 __slab_alloc.constprop.0+0x95/0xe0 mm/slub.c:2781
 slab_alloc_node mm/slub.c:2857 [inline]
 slab_alloc mm/slub.c:2900 [inline]
 __kmalloc+0x34a/0x3e0 mm/slub.c:3981
 kmalloc include/linux/slab.h:557 [inline]
 sk_prot_alloc+0x133/0x260 net/core/sock.c:1685
 sk_alloc+0x27/0x8d0 net/core/sock.c:1739
 l2cap_sock_alloc.constprop.0+0x22/0x200 net/bluetooth/l2cap_sock.c:1805
 l2cap_sock_create+0xc8/0x160 net/bluetooth/l2cap_sock.c:1851
 bt_sock_create+0x142/0x2e0 net/bluetooth/af_bluetooth.c:130
 __sock_create+0x26b/0x580 net/socket.c:1406
 sock_create net/socket.c:1457 [inline]
 __sys_socket+0xd6/0x1a0 net/socket.c:1499
 __do_sys_socket net/socket.c:1508 [inline]
 __se_sys_socket net/socket.c:1506 [inline]
 __x64_sys_socket+0x6a/0xb0 net/socket.c:1506
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1271 [inline]
 __free_pages_ok+0x4da/0xed0 mm/page_alloc.c:1536
 unfreeze_partials+0x16c/0x1b0 mm/slub.c:2359
 put_cpu_partial+0x129/0x200 mm/slub.c:2395
 qlink_free mm/kasan/quarantine.c:146 [inline]
 qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165
 quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272
 ____kasan_kmalloc.constprop.0+0x98/0xa0 mm/kasan/common.c:412
 kasan_slab_alloc include/linux/kasan.h:209 [inline]
 slab_post_alloc_hook mm/slab.h:512 [inline]
 slab_alloc_node mm/slub.c:2892 [inline]
 slab_alloc mm/slub.c:2900 [inline]
 kmem_cache_alloc+0x1c6/0x440 mm/slub.c:2905
 create_nsproxy kernel/nsproxy.c:56 [inline]
 create_new_namespaces+0x2b/0x920 kernel/nsproxy.c:74
 prepare_nsset kernel/nsproxy.c:316 [inline]
 __do_sys_setns+0x1e7/0x1190 kernel/nsproxy.c:551
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Memory state around the buggy address:
 ffff88802f43bf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88802f43c000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802f43c080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff88802f43c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88802f43c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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