syzbot

ODEBUG: object ffff8880aea07cc0 is NOT on stack ffff888046ac0000, but annotated.
------------[ cut here ]------------
WARNING: CPU: 0 PID: 13697 at lib/debugobjects.c:330 debug_object_is_on_stack lib/debugobjects.c:324 [inline]
WARNING: CPU: 0 PID: 13697 at lib/debugobjects.c:330 __debug_object_init.cold+0x1d0/0x2be lib/debugobjects.c:356
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 13697 Comm: syz-executor.5 Not tainted 4.14.174-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x13e/0x194 lib/dump_stack.c:58
 panic+0x1f9/0x42d kernel/panic.c:183
 __warn.cold+0x2f/0x30 kernel/panic.c:547
 report_bug+0x20a/0x248 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:177 [inline]
 fixup_bug arch/x86/kernel/traps.c:172 [inline]
 do_error_trap+0x195/0x2d0 arch/x86/kernel/traps.c:295
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:963
RIP: 0010:debug_object_is_on_stack lib/debugobjects.c:330 [inline]
RIP: 0010:__debug_object_init.cold+0x1d0/0x2be lib/debugobjects.c:356
RSP: 0018:ffff8880aea07b70 EFLAGS: 00010086
RAX: 0000000000000050 RBX: 1ffff11015d40f75 RCX: 0000000000000000
RDX: 0000000000000100 RSI: ffffffff86ac07e0 RDI: ffffed1015d40f64
RBP: ffff8880aea07cc0 R08: 0000000000000050 R09: ffff88805cedb198
R10: fffffbfff14a8cd7 R11: ffff88809ade0140 R12: 00000000000e35c0
R13: ffff88805cedb188 R14: ffff88809ade0140 R15: ffffffff8a744448
 init_rcu_head_on_stack kernel/rcu/update.c:449 [inline]
 __wait_rcu_gp+0x83/0x2e0 kernel/rcu/update.c:394
 synchronize_rcu.part.0+0x9b/0xa0 kernel/rcu/tree_plugin.h:764
 __l2tp_session_unhash+0x36a/0x500 net/l2tp/l2tp_core.c:1745
 l2tp_tunnel_closeall+0x1f6/0x370 net/l2tp/l2tp_core.c:1341
 l2tp_tunnel_destruct+0x361/0x660 net/l2tp/l2tp_core.c:1295
 __sk_destruct+0x49/0x640 net/core/sock.c:1556
 __rcu_reclaim kernel/rcu/rcu.h:195 [inline]
 rcu_do_batch kernel/rcu/tree.c:2699 [inline]
 invoke_rcu_callbacks kernel/rcu/tree.c:2962 [inline]
 __rcu_process_callbacks kernel/rcu/tree.c:2929 [inline]
 rcu_process_callbacks+0x792/0x1190 kernel/rcu/tree.c:2946
 __do_softirq+0x254/0x9bf kernel/softirq.c:288
 invoke_softirq kernel/softirq.c:368 [inline]
 irq_exit+0x15b/0x1a0 kernel/softirq.c:409
 exiting_irq arch/x86/include/asm/apic.h:648 [inline]
 smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1102
 apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792
 </IRQ>
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x50/0x80 kernel/locking/spinlock.c:200
RSP: 0018:ffff888046ac7a18 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10
RAX: 1ffffffff0fa2cd3 RBX: ffff88809ade0140 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff88809ade09bc
RBP: ffff8880aea2b540 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880aea2b540
R13: ffff8880870f4440 R14: 0000000000000000 R15: ffff8880aea2be90
 finish_lock_switch kernel/sched/sched.h:1346 [inline]
 finish_task_switch+0x178/0x620 kernel/sched/core.c:2675
 context_switch kernel/sched/core.c:2811 [inline]
 __schedule+0x7c0/0x1ca0 kernel/sched/core.c:3384
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 pipe_wait+0xe2/0x190 fs/pipe.c:121
 splice_from_pipe_next.part.0+0x86/0x290 fs/splice.c:566
 splice_from_pipe_next fs/splice.c:545 [inline]
 __splice_from_pipe+0xf9/0x740 fs/splice.c:624
 vmsplice_to_user+0x197/0x1c0 fs/splice.c:1272
 SYSC_vmsplice fs/splice.c:1353 [inline]
 SyS_vmsplice+0x12a/0x150 fs/splice.c:1334
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c849
RSP: 002b:00007f78680d9c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000116
RAX: ffffffffffffffda RBX: 00007f78680da6d4 RCX: 000000000045c849
RDX: 0000000000000001 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 000000000076bfa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000c47 R14: 00000000004ce688 R15: 000000000076bfac

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