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WARNING: CPU: 1 PID: 3040 at net/key/af_key.c:111 pfkey_sock_destruct+0x30e/0x350 net/key/af_key.c:111()
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 3040 Comm: syz-executor.4 Not tainted 4.4.174+ #17
 0000000000000000 9af19deb675751f9 ffff8801bcf5fb38 ffffffff81aad1a1
 0000000000000000 ffffffff82835ee0 ffffffff82ab39a0 000000000000006f
 ffffffff826e409e ffff8801bcf5fc18 ffffffff813a48c2 0000000041b58ab3
Call Trace:
 [<ffffffff81aad1a1>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81aad1a1>] dump_stack+0xc1/0x120 lib/dump_stack.c:51
 [<ffffffff813a48c2>] panic+0x1b9/0x37b kernel/panic.c:112
 [<ffffffff813a4ab9>] warn_slowpath_common kernel/panic.c:455 [inline]
 [<ffffffff813a4ab9>] warn_slowpath_common.cold+0x20/0x20 kernel/panic.c:435
 [<ffffffff810d3aaa>] warn_slowpath_null+0x2a/0x30 kernel/panic.c:492
 [<ffffffff826e409e>] pfkey_sock_destruct+0x30e/0x350 net/key/af_key.c:111
 [<ffffffff821e9d10>] sk_destruct+0x50/0x4e0 net/core/sock.c:1448
 [<ffffffff821ea1f4>] __sk_free+0x54/0x230 net/core/sock.c:1481
 [<ffffffff821ea404>] sk_free+0x34/0x40 net/core/sock.c:1492
 [<ffffffff826e6727>] sock_put include/net/sock.h:1643 [inline]
 [<ffffffff826e6727>] pfkey_release+0x277/0x310 net/key/af_key.c:194
 [<ffffffff821d36a5>] __sock_release+0xd5/0x260 net/socket.c:592
 [<ffffffff821d384b>] sock_close+0x1b/0x30 net/socket.c:1050
 [<ffffffff8149c8c6>] __fput+0x246/0x710 fs/file_table.c:208
 [<ffffffff8149ce16>] ____fput+0x16/0x20 fs/file_table.c:244
 [<ffffffff8112f352>] task_work_run+0x202/0x2b0 kernel/task_work.c:115
 [<ffffffff81003dca>] tracehook_notify_resume include/linux/tracehook.h:191 [inline]
 [<ffffffff81003dca>] exit_to_usermode_loop+0x14a/0x170 arch/x86/entry/common.c:188
 [<ffffffff810064b9>] prepare_exit_to_usermode arch/x86/entry/common.c:221 [inline]
 [<ffffffff810064b9>] syscall_return_slowpath arch/x86/entry/common.c:286 [inline]
 [<ffffffff810064b9>] do_syscall_32_irqs_on arch/x86/entry/common.c:336 [inline]
 [<ffffffff810064b9>] do_fast_syscall_32+0x7a9/0xa90 arch/x86/entry/common.c:397
 [<ffffffff8271a350>] sysenter_flags_fixed+0xd/0x1a
Kernel Offset: disabled
Rebooting in 86400 seconds..