BUG: spinlock bad magic on CPU#0, kworker/0:4/6751
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BUG: KASAN: slab-out-of-bounds in task_pid_nr include/linux/sched.h:1366 [inline]
BUG: KASAN: slab-out-of-bounds in spin_dump kernel/locking/spinlock_debug.c:65 [inline]
BUG: KASAN: slab-out-of-bounds in spin_bug.cold+0x95/0x9e kernel/locking/spinlock_debug.c:75
Read of size 4 at addr ffff88806498a848 by task kworker/0:4/6751

CPU: 0 PID: 6751 Comm: kworker/0:4 Not tainted 5.10.0-rc3-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:77 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0xae/0x4c8 mm/kasan/report.c:385
 __kasan_report mm/kasan/report.c:545 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:562
 task_pid_nr include/linux/sched.h:1366 [inline]
 spin_dump kernel/locking/spinlock_debug.c:65 [inline]
 spin_bug.cold+0x95/0x9e kernel/locking/spinlock_debug.c:75
 debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline]
 do_raw_spin_lock+0x216/0x2b0 kernel/locking/spinlock_debug.c:112
 spin_lock_bh include/linux/spinlock.h:359 [inline]
 lock_sock_nested+0x3b/0x110 net/core/sock.c:3036
 l2cap_sock_teardown_cb+0xa1/0x660 net/bluetooth/l2cap_sock.c:1520
 l2cap_chan_del+0xbc/0xa80 net/bluetooth/l2cap_core.c:618
 l2cap_chan_close+0x1bc/0xaf0 net/bluetooth/l2cap_core.c:823
 l2cap_chan_timeout+0x17e/0x2f0 net/bluetooth/l2cap_core.c:436
 process_one_work+0x933/0x15a0 kernel/workqueue.c:2272
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2418
 kthread+0x3af/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Allocated by task 10840:
 kasan_save_stack+0x1b/0x40 mm/kasan/common.c:48
 kasan_set_track mm/kasan/common.c:56 [inline]
 __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:461
 kmalloc include/linux/slab.h:557 [inline]
 kzalloc include/linux/slab.h:664 [inline]
 __register_sysctl_table+0x112/0x1090 fs/proc/proc_sysctl.c:1314
 __addrconf_sysctl_register+0x1db/0x3d0 net/ipv6/addrconf.c:6929
 addrconf_sysctl_register net/ipv6/addrconf.c:6976 [inline]
 addrconf_sysctl_register+0x139/0x1d0 net/ipv6/addrconf.c:6965
 ipv6_add_dev+0x926/0x10f0 net/ipv6/addrconf.c:443
 addrconf_notify+0x8d7/0x23f0 net/ipv6/addrconf.c:3487
 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83
 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:2035
 call_netdevice_notifiers_extack net/core/dev.c:2047 [inline]
 call_netdevice_notifiers net/core/dev.c:2061 [inline]
 register_netdevice+0x1068/0x1630 net/core/dev.c:9999
 macvlan_common_newlink+0xc25/0x1560 drivers/net/macvlan.c:1489
 __rtnl_newlink+0x108b/0x1740 net/core/rtnetlink.c:3441
 rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3500
 rtnetlink_rcv_msg+0x44e/0xad0 net/core/rtnetlink.c:5562
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 netlink_unicast_kernel net/netlink/af_netlink.c:1304 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1330
 netlink_sendmsg+0x856/0xd90 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:651 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:671
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2353
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2407
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2440
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

The buggy address belongs to the object at ffff88806498a000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 72 bytes to the right of
 2048-byte region [ffff88806498a000, ffff88806498a800)
The buggy address belongs to the page:
page:00000000d88d9daa refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x64988
head:00000000d88d9daa order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head)
raw: 00fff00000010200 0000000000000000 0000000100000001 ffff888010042000
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff88806498a700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88806498a780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88806498a800: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                              ^
 ffff88806498a880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88806498a900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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