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BUG: KASAN: use-after-free in __lock_acquire+0x3d86/0x54a0 kernel/locking/lockdep.c:4885
Read of size 8 at addr ffff88802b40f120 by task kworker/1:7/8555

CPU: 1 PID: 8555 Comm: kworker/1:7 Not tainted 5.15.0-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:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0x6c/0x309 mm/kasan/report.c:256
 __kasan_report mm/kasan/report.c:442 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
 __lock_acquire+0x3d86/0x54a0 kernel/locking/lockdep.c:4885
 lock_acquire kernel/locking/lockdep.c:5625 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590
 lock_sock_nested+0x2f/0xf0 net/core/sock.c:3203
 l2cap_sock_teardown_cb+0xa1/0x660 net/bluetooth/l2cap_sock.c:1528
 l2cap_chan_del+0xbc/0xa80 net/bluetooth/l2cap_core.c:622
 l2cap_chan_close+0x1b9/0xaf0 net/bluetooth/l2cap_core.c:825
 l2cap_chan_timeout+0x17e/0x2f0 net/bluetooth/l2cap_core.c:436
 process_one_work+0x9bf/0x16b0 kernel/workqueue.c:2297
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2444
 kthread+0x3e5/0x4d0 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the page:
page:ffffea0000ad03c0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2b40f
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 0000000000000000 ffffea0000ad03c8 0000000000000000
raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 14911, ts 2743503221735, free_ts 2756327755563
 prep_new_page mm/page_alloc.c:2424 [inline]
 get_page_from_freelist+0xa72/0x2f80 mm/page_alloc.c:4153
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5375
 alloc_pages+0x1a7/0x300 mm/mempolicy.c:2191
 alloc_slab_page mm/slub.c:1770 [inline]
 allocate_slab mm/slub.c:1907 [inline]
 new_slab+0x319/0x490 mm/slub.c:1970
 ___slab_alloc+0x950/0x1050 mm/slub.c:3001
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3088
 slab_alloc_node mm/slub.c:3179 [inline]
 slab_alloc mm/slub.c:3221 [inline]
 kmem_cache_alloc+0x365/0x390 mm/slub.c:3226
 getname_kernel+0x4e/0x370 fs/namei.c:226
 kernel_execve+0x24/0x460 fs/exec.c:1941
 call_usermodehelper_exec_async+0x2e3/0x580 kernel/umh.c:112
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1338 [inline]
 free_pcp_prepare+0x2c5/0x780 mm/page_alloc.c:1389
 free_unref_page_prepare mm/page_alloc.c:3315 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3394
 __unfreeze_partials+0x340/0x360 mm/slub.c:2502
 qlink_free mm/kasan/quarantine.c:146 [inline]
 qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272
 __kasan_slab_alloc+0x95/0xb0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook mm/slab.h:519 [inline]
 slab_alloc_node mm/slub.c:3213 [inline]
 kmem_cache_alloc_node+0x259/0x3d0 mm/slub.c:3249
 __alloc_skb+0x20b/0x340 net/core/skbuff.c:415
 alloc_skb include/linux/skbuff.h:1116 [inline]
 nlmsg_new include/net/netlink.h:953 [inline]
 inet_netconf_notify_devconf+0xdd/0x250 net/ipv4/devinet.c:2094
 __devinet_sysctl_unregister net/ipv4/devinet.c:2604 [inline]
 devinet_sysctl_unregister net/ipv4/devinet.c:2628 [inline]
 inetdev_destroy net/ipv4/devinet.c:324 [inline]
 inetdev_event+0xcd6/0x15d0 net/ipv4/devinet.c:1598
 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83
 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1996
 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline]
 call_netdevice_notifiers net/core/dev.c:2022 [inline]
 unregister_netdevice_many+0x951/0x1790 net/core/dev.c:11043
 ip_tunnel_delete_nets+0x39f/0x5b0 net/ipv4/ip_tunnel.c:1123
 ops_exit_list+0x10d/0x160 net/core/net_namespace.c:171
 cleanup_net+0x4ea/0xb00 net/core/net_namespace.c:591

Memory state around the buggy address:
 ffff88802b40f000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802b40f080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff88802b40f100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                               ^
 ffff88802b40f180: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802b40f200: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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