syzbot

RBP: 00007f43c7daa1d0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffd996d23ef R14: 00007f43c7daa300 R15: 0000000000022000
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 1 PID: 23251 Comm: kworker/1:12 Not tainted 4.14.225-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events l2cap_chan_timeout
task: ffff888052a943c0 task.stack: ffff88803b8c0000
RIP: 0010:lock_accessed kernel/locking/lockdep.c:979 [inline]
RIP: 0010:__bfs.part.0+0x20e/0x470 kernel/locking/lockdep.c:1045
RSP: 0018:ffff88803b8c7808 EFLAGS: 00010003
RAX: 0000000001d0e397 RBX: ffffffff8bae8560 RCX: 0000000000000000
RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000010
RBP: ffff88803b8c78c0 R08: 0000000000000000 R09: 00000000000043f6
R10: 0000000000145fe7 R11: 0000000000066071 R12: ffffffff8140db70
R13: 0000000000000000 R14: 0000000000000000 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055be9f58b800 CR3: 0000000050801000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __bfs kernel/locking/lockdep.c:1424 [inline]
 __bfs_backwards kernel/locking/lockdep.c:1082 [inline]
 find_usage_backwards kernel/locking/lockdep.c:1424 [inline]
 check_usage_backwards+0x167/0x2c0 kernel/locking/lockdep.c:2713
 mark_lock_irq kernel/locking/lockdep.c:2804 [inline]
 mark_lock+0x3c7/0x1050 kernel/locking/lockdep.c:3194
 mark_irqflags kernel/locking/lockdep.c:3086 [inline]
 __lock_acquire+0xcf9/0x3f20 kernel/locking/lockdep.c:3448
 lock_acquire+0x170/0x3f0 kernel/locking/lockdep.c:3998
 __raw_spin_lock_bh include/linux/spinlock_api_smp.h:135 [inline]
 _raw_spin_lock_bh+0x2f/0x40 kernel/locking/spinlock.c:176
 spin_lock_bh include/linux/spinlock.h:322 [inline]
 lock_sock_nested+0x39/0x100 net/core/sock.c:2788
 l2cap_sock_teardown_cb+0x93/0x650 net/bluetooth/l2cap_sock.c:1341
 l2cap_chan_del+0xaf/0x950 net/bluetooth/l2cap_core.c:599
 l2cap_chan_close+0x103/0x870 net/bluetooth/l2cap_core.c:757
 l2cap_chan_timeout+0x143/0x2a0 net/bluetooth/l2cap_core.c:430
 process_one_work+0x793/0x14a0 kernel/workqueue.c:2116
 worker_thread+0x5cc/0xff0 kernel/workqueue.c:2250
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
Code: 78 01 00 00 4d 8b 36 4c 39 f3 74 78 49 8d 7e 10 4c 89 f0 4c 8b 0d 63 02 a6 0a 48 89 fa 48 2d 20 1a c7 8b 48 c1 ea 03 48 c1 f8 06 <42> 80 3c 3a 00 0f 85 28 01 00 00 49 8b 4e 10 4c 8d 41 2c 4c 89 
RIP: lock_accessed kernel/locking/lockdep.c:979 [inline] RSP: ffff88803b8c7808
RIP: __bfs.part.0+0x20e/0x470 kernel/locking/lockdep.c:1045 RSP: ffff88803b8c7808
---[ end trace 3186a1228a989312 ]---