WARNING in inet_sock_destruct

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 01364dad Linux 4.14.174
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=144dfcb7e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=664dd71881ab2b2d
dashboard link: https://syzkaller.appspot.com/bug?extid=aa53e7ab323a68c05267
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11210697e00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=124dfcb7e00000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+aa53e7...@syzkaller.appspotmail.com

audit: type=1400 audit(1585796459.071:36): avc: denied { map } for pid=7343 comm="syz-executor015" path="/root/syz-executor015481933" dev="sda1" ino=16483 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
------------[ cut here ]------------
WARNING: CPU: 0 PID: 0 at net/ipv4/af_inet.c:153 inet_sock_destruct+0x575/0x730 net/ipv4/af_inet.c:153
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 0 Comm: swapper/0 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:inet_sock_destruct+0x575/0x730 net/ipv4/af_inet.c:153
RSP: 0018:ffff8880aea07d80 EFLAGS: 00010206
RAX: ffffffff87c76240 RBX: ffffffff8877e1a0 RCX: 0000000000000001
RDX: 0000000000000100 RSI: 0000000000000000 RDI: ffff888090388abc
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff888090388880
R13: ffff8880903889b8 R14: ffff888092694b58 R15: ffff88809af546c0
l2tp_tunnel_destruct+0x3d7/0x660 net/l2tp/l2tp_core.c:1302
__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:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
RSP: 0018:ffffffff87c07e78 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10
RAX: 1ffffffff0fa2cd4 RBX: dffffc0000000000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffffffff87c76abc
RBP: ffffffff87d16690 R08: 1ffffffff1124101 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: fffffbfff0f8ec48
R13: ffffffff87c76240 R14: 0000000000000000 R15: 0000000000000000
arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
default_idle+0x47/0x370 arch/x86/kernel/process.c:566
cpuidle_idle_call kernel/sched/idle.c:156 [inline]
do_idle+0x250/0x3c0 kernel/sched/idle.c:246
cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:351
start_kernel+0x659/0x676 init/main.c:708
secondary_startup_64+0xa5/0xb0 arch/x86/kernel/head_64.S:240
Kernel Offset: disabled
Rebooting in 86400 seconds..


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