Warning: Permanently added '10.128.10.5' (ECDSA) to the list of known hosts.
executing program
[   39.651259][ T3584] 
[   39.653624][ T3584] ============================================
[   39.659753][ T3584] WARNING: possible recursive locking detected
[   39.665877][ T3584] 5.15.98-syzkaller #0 Not tainted
[   39.670980][ T3584] --------------------------------------------
[   39.677132][ T3584] syz-executor183/3584 is trying to acquire lock:
[   39.683527][ T3584] ffff888016d87120 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: l2tp_tunnel_register+0xafb/0x1c90
[   39.693340][ T3584] 
[   39.693340][ T3584] but task is already holding lock:
[   39.700680][ T3584] ffff888016d86120 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: pppol2tp_connect+0x65b/0x1680
[   39.710128][ T3584] 
[   39.710128][ T3584] other info that might help us debug this:
[   39.718161][ T3584]  Possible unsafe locking scenario:
[   39.718161][ T3584] 
[   39.725584][ T3584]        CPU0
[   39.728860][ T3584]        ----
[   39.732117][ T3584]   lock(sk_lock-AF_PPPOX);
[   39.736595][ T3584]   lock(sk_lock-AF_PPPOX);
[   39.741072][ T3584] 
[   39.741072][ T3584]  *** DEADLOCK ***
[   39.741072][ T3584] 
[   39.749189][ T3584]  May be due to missing lock nesting notation
[   39.749189][ T3584] 
[   39.757483][ T3584] 1 lock held by syz-executor183/3584:
[   39.762913][ T3584]  #0: ffff888016d86120 (sk_lock-AF_PPPOX){+.+.}-{0:0}, at: pppol2tp_connect+0x65b/0x1680
[   39.772818][ T3584] 
[   39.772818][ T3584] stack backtrace:
[   39.778679][ T3584] CPU: 1 PID: 3584 Comm: syz-executor183 Not tainted 5.15.98-syzkaller #0
[   39.787161][ T3584] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
[   39.797191][ T3584] Call Trace:
[   39.800449][ T3584]  <TASK>
[   39.803360][ T3584]  dump_stack_lvl+0x1e3/0x2cb
[   39.808015][ T3584]  ? io_uring_drop_tctx_refs+0x19d/0x19d
[   39.813621][ T3584]  ? panic+0x84d/0x84d
[   39.817666][ T3584]  validate_chain+0x46cf/0x58b0
[   39.822514][ T3584]  ? reacquire_held_locks+0x660/0x660
[   39.827864][ T3584]  ? register_lock_class+0x100/0x9a0
[   39.833129][ T3584]  ? mark_lock+0x98/0x340
[   39.837434][ T3584]  ? is_dynamic_key+0x1e0/0x1e0
[   39.842278][ T3584]  ? __lock_acquire+0x1295/0x1ff0
[   39.847277][ T3584]  ? mark_lock+0x98/0x340
[   39.851582][ T3584]  __lock_acquire+0x1295/0x1ff0
[   39.856411][ T3584]  lock_acquire+0x1f6/0x560
[   39.860897][ T3584]  ? l2tp_tunnel_register+0xafb/0x1c90
[   39.866350][ T3584]  ? read_lock_is_recursive+0x10/0x10
[   39.871701][ T3584]  ? __fget_files+0x3cf/0x440
[   39.876362][ T3584]  lock_sock_nested+0x44/0x100
[   39.881104][ T3584]  ? l2tp_tunnel_register+0xafb/0x1c90
[   39.886541][ T3584]  l2tp_tunnel_register+0xafb/0x1c90
[   39.891805][ T3584]  ? l2tp_tunnel_del_work+0x340/0x340
[   39.897152][ T3584]  ? memset+0x1f/0x40
[   39.901113][ T3584]  ? lockdep_init_map_type+0x9d/0x8d0
[   39.906460][ T3584]  ? lockdep_softirqs_off+0x420/0x420
[   39.911836][ T3584]  ? l2tp_tunnel_create+0x8e/0x440
[   39.916927][ T3584]  ? l2tp_tunnel_create+0x246/0x440
[   39.922100][ T3584]  pppol2tp_connect+0xafb/0x1680
[   39.927016][ T3584]  ? pppol2tp_release+0x320/0x320
[   39.932031][ T3584]  ? aa_af_perm+0x350/0x350
[   39.936520][ T3584]  ? bpf_lsm_socket_connect+0x5/0x10
[   39.941788][ T3584]  ? security_socket_connect+0x7d/0xa0
[   39.947226][ T3584]  ? pppol2tp_release+0x320/0x320
[   39.952231][ T3584]  __sys_connect+0x38b/0x410
[   39.956822][ T3584]  ? __sys_connect_file+0x170/0x170
[   39.962004][ T3584]  ? syscall_enter_from_user_mode+0x2e/0x290
[   39.967964][ T3584]  ? lockdep_hardirqs_on+0x94/0x130
[   39.973148][ T3584]  __x64_sys_connect+0x76/0x80
[   39.977915][ T3584]  do_syscall_64+0x3d/0xb0
[   39.982310][ T3584]  entry_SYSCALL_64_after_hwframe+0x61/0xcb
[   39.988185][ T3584] RIP: 0033:0x7f09903b40a9
[   39.992577][ T3584] Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
[   40.012159][ T3584] RSP: 002b:00007ffc0ce9c4c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
[   40.020548][ T3584] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f09903b40a9
[   40.028509][ T3584] RDX: 000000000000003a RSI: 0000000020000200 RDI: 0000000000000003
[   40.036461][ T3584] RBP: 00007f0990378090 R08: 0000000000000000 R09: 0000000000000000
[   40.044414][ T3584] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f0990378120
[   40.05